Comtech EF Data SDM-650B User Manual

SDM-650B

Satellite Modem Installation and Operation Manual

Part Number MN/SDM650B.IOM Revision 5

EFData Corporation is an ISO 9001 Registered Company

SDM-650B

Satellite Modem Installation and Operation Manual

Part Number MN/SDM650B.IOM Revision 5 May 28, 1996

Special Instructions:

This is the sixth edition of the manual.

Change bars were not utilized.

This revision supersedes part number MN/SDM650 Rev. 4 dated May 5, 1995.

EFData Corporation, 2105 West 5th Place, Tempe, Arizona 85281 USA, (602) 968-0447, FAX: (602) 921-9012.

Warranty Policy

This EFData Corporation product is warranted against defects in material and workmanship for a period of one year from the date of shipment. During the warranty period, EFData will, at its option, repair or replace products that prove to be defective.

For equipment under warranty, the customer is responsible for freight to EFData and all related custom, taxes, tariffs, insurance, etc. EFData is responsible for the freight charges only for return of the equipment from the factory to the customer. EFData will return the equipment by the same method (i.e., Air, Express, Surface) as the equipment was sent to EFData.

Limitations of Warranty

The foregoing warranty shall not apply to defects resulting from improper installation or maintenance, abuse, unauthorized modification, or operation outside of environmental specifications for the product, or, for damages that occur due to improper repackaging of equipment for return to EFData.

No other warranty is expressed or implied. EFData Corporation specifically disclaims the implied warranties of merchantability and fitness for particular purpose.

Exclusive Remedies

The remedies provided herein are the buyer's sole and exclusive remedies. EFData Corporation shall not be liable for any direct, indirect, special, incidental, or consequential damages, whether based on contact, tort, or any other legal theory.

Disclaimer

EFData has reviewed this manual thoroughly in order that it will be an easy-to-use guide to your equipment. All statements, technical information, and recommendations in this manual and in any guides or related documents are believed reliable, but the accuracy and completeness thereof are not guaranteed or warranted, and they are not intended to be, nor should they be understood to be, representations or warranties concerning the products described. Further, EFData reserves the right to make changes in the specifications of the products described in this manual at any time without notice and without obligation to notify any person of such changes.

If you have any questions regarding your equipment or the information in this manual, please contact the EFData Customer Support Department. (For more information, refer to the preface.)

About this Manual

This manual provides installation and operation information for the EFData SDM-650B satellite modem.

This is a technical document intended for earth station engineers, technicians, and operators responsible for the operation and maintenance of the SDM-650B satellite modem.

Preface

Organization

This manual includes the following chapters and appendixes:

• Chapter 1 — describes the unit’s purpose, function, description, options, and

system specification.

• Chapter 2 — describes the unit’s installation process, external connectors, and

system requirements.

• Chapter 3 — describes the unit’s configuration.

• Chapter 4 — provides front panel operation information.

• Chapter 5 — describes the unit’s theory of operation.

• Chapter 6 — describes the maintenance of the unit, and provides troubleshooting

assistance.

• Appendix A — provides data rate change instructions and the differences for

fixed and variable rate filters.

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Preface SDM-650B Satellite Modem

• Appendix B — describes the unit’s remote control operation protocol and

command structure.

• Appendix C — provides field compatibility specifications.

• Appendix D — provides software change instructions.

• Appendix E — describes the unit’s Automatic Gain Control (AGC) interface

option.

• Appendix F — describes the asynchronous overhead channel unit option.

• Appendix G — describes the Trojan interface option.

• Glossary.

Conventions Used in this Manual

Cautions and Warnings

CAUTION indicates a hazardous situation that, if not avoided, may result in minor or moderate injury. CAUTION may also be used to indicate other

CAUTION

WARN ING

unsafe practices or risks of property damage.

WARNING indicates a potentially hazardous situation that, if not avoided, could result in death or serious injury.

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SDM-8000 Satellite Modem Preface

References Used in this Manual

Military Standards

References to “MIL-STD-188” apply to the 114A series (i.e., MIL-STD-188-114A), which provides electrical and functional characteristics of the unbalanced and balanced voltage digital interface circuits applicable to both long haul and tactical communications. Specifically, these references apply to the MIL-STD-188-114A electrical characteristics for a balanced voltage digital interface circuit, Type 1 generator, for the full range of data rates.

For more information, refer to the following document:

• Department of Defense (DOD) MIL-STD-188-114A, “Electrical Characteristics of Digital Interface Circuits.”

Trademarks

Product names mentioned in this manual may be trademarks or registered trademarks of their respective companies and are hereby acknowledged.

European EMC Directive

In order to meet the European Electro-Magnetic Compatibility (EMC) Directive (EN55022, EN50082-1), properly shielded cables for DATA I/O are required. More specifically, these cables must be double-shielded from end-to-end, ensuring a continuous ground shield.

The following information is applicable for the European Low Voltage Directive (EN60950):

<HAR> Type of power cord required for use in the European Community.

CAUTION: Double-pole/Neutral Fusing

International Symbols:

ACHTUNG: Zweipolige bzw. Neutralleiter-Sicherung

Alternating Current.

Fuse. Safety Ground.

Chassis Ground.

Note: For additional symbols, refer to “Cautions and Warnings” listed earlier in this preface.

Reporting Comments or Suggestions Concerning this Manual

Comments and suggestions regarding the content and design of this manual will be appreciated. To submit comments, please contact the EFData Customer Support Department according to the following information.

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SDM-8000 Satellite Modem Preface

Customer Support

Contact the EFData Customer Support Department for:

• Product support

• Information on returning a product

• Information on upgrading a product

• Product training

• Reporting comments or suggestions concerning manuals

An EFData Customer Support representative may be reached at:

EFData Corporation Attention: Customer Support Department 2105 West 5th Place Tempe, Arizona 85281 USA

(602) 968-0447 (Main EFData Number) (602) 517-2444 (Customer Support Desk) (602) 921-9012 FAX

or, E-Mail can be sent to the Customer Support Department at:

service@efdata.com

To return an EFData product (in-warranty and out-of-warranty) for repair or replacement:

1. Request a Return Material Authorization (RMA) number from the EFData Customer Support Department.

Be prepared to supply the Customer Support representative with the model

number, serial number, and a description of the problem.

2. To ensure that the product is not damaged during shipping, pack the product in its original shipping carton/packaging.

3. Ship the product back to EFData. (Shipping charges should be prepaid.)

For more information regarding the warranty policies, refer to the disclaimer page located behind the title page.

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This page is intentionally left blank.

vi Rev. 5

CHAPTER 1. INTRODUCTION.................................................................................. 1–1

1.1 Purpose and Function ..................................................................................................................................1–2

1.2 Description....................................................................................................................................................1–3

1.3 System Specification.....................................................................................................................................1–5

CHAPTER 2. INSTALLATION................................................................................... 2–1

2.1 Unpacking .....................................................................................................................................................2–1

2.2 External Connections................................................................................................................................... 2–2

2.2.1 DATA I/O...............................................................................................................................................2–3

2.2.2 Remote (J6).............................................................................................................................................2–3

2.2.3 Fault (J7).................................................................................................................................................2–3

2.2.4 IF Output (CP1) ......................................................................................................................................2–4

2.2.5 IF Input (CP2)......................................................................................................................................... 2–4

2.2.6 AC Power ...............................................................................................................................................2–4

2.2.7 GROUND ...............................................................................................................................................2–5

2.3 System Requirements...................................................................................................................................2–5

2.4 System Installation.......................................................................................................................................2–6

CHAPTER 3. CONFIGURATION............................................................................... 3–1

3.1 Monitor and Control.................................................................................................................................... 3–1

3.1.1 Description of Options............................................................................................................................3–2

3.1.1.1 Remote Interface .............................................................................................................................3–2

3.1.1.2 Remote Baud Rate...........................................................................................................................3–3

3.1.1.3 Remote Address ..............................................................................................................................3–4

3.1.1.4 Battery ............................................................................................................................................. 3–4

3.1.1.5 Modulator/Coder Defaults............................................................................................................... 3–5

3.1.1.6 Demodulator/Decoder Defaults....................................................................................................... 3–5

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3.1.1.7 Utility Defaults ................................................................................................................................3–5

3.1.2 Remote Interface Specification............................................................................................................... 3–6

3.1.3 M&C Theory of Operation ..................................................................................................................... 3–6

3.2 Digital Interfaces ..........................................................................................................................................3–7

3.2.1 RS-422 and MIL-STD-188-114 Interface ..............................................................................................3–7

3.2.1.1 Functional Description ....................................................................................................................3–7

3.2.1.2 Connector Pinouts .........................................................................................................................3–12

3.2.1.3 Specification..................................................................................................................................3–13

3.2.2 V.35 Interface ....................................................................................................................................... 3–14

3.2.2.1 Functional Description ..................................................................................................................3–14

3.2.2.2 Connector Pinouts .........................................................................................................................3–18

3.2.2.3 Specification..................................................................................................................................3–19

3.2.3 DS-1 Interface.......................................................................................................................................3–20

3.2.3.1 Functional Description ..................................................................................................................3–20

3.2.3.2 Connector Pinouts .........................................................................................................................3–23

3.2.3.3 Specification..................................................................................................................................3–23

3.2.4 G.703, 2048 kbit/s Interface .................................................................................................................3–24

3.2.4.1 Functional Description ..................................................................................................................3–24

3.2.4.2 Optional EXT CLK .......................................................................................................................3–26

3.2.4.3 Switch Configuration for G.703 2048 kbit/s Interface..................................................................3–27

3.2.4.4 Connector Pinouts .........................................................................................................................3–27

3.2.4.5 G.703 2048 kbit/s Connector Board Option.................................................................................. 3–28

3.2.4.6 External Reference (J3) .................................................................................................................3–30

3.2.4.7 Send Data (J4) ............................................................................................................................... 3–30

3.2.4.8 Receive Data (J5) ..........................................................................................................................3–30

3.2.4.9 Specification..................................................................................................................................3–31

3.2.5 Asynchronous Overhead Interface........................................................................................................3–31

3.2.5.1 Functional Description ..................................................................................................................3–31

3.2.5.2 Terrestrial Interface ....................................................................................................................... 3–32

3.2.5.3 Multiplexer ....................................................................................................................................3–35

3.2.5.4 Demultiplexer................................................................................................................................3–35

3.2.5.5 Plesiochronous Buffer ...................................................................................................................3–36

3.2.5.6 Remote Interface Specification .....................................................................................................3–36

3.2.5.7 Interface Connector Pinouts .......................................................................................................... 3–37

3.2.5.8 Asynchronous Interface Specifications .........................................................................................3–38

3.2.6 Asynchronous Breakout Panel.............................................................................................................. 3–39

3.3 Doppler Buffer............................................................................................................................................3–40

3.3.1 Buffer Setup.......................................................................................................................................... 3–44

3.3.1.1 Buffer Size.....................................................................................................................................3–46

3.3.1.2 Doppler..........................................................................................................................................3–46

3.3.1.3 Plesiochronous ..............................................................................................................................3–47

3.3.1.4 Frame/Multiframe Length ............................................................................................................. 3–47

3.3.1.5 Total Buffer Length.......................................................................................................................3–48

3.3.1.6 Converting.....................................................................................................................................3–48

3.4 Doppler Buffer Specification..................................................................................................................... 3–49

3.5 I/O Connectors ...........................................................................................................................................3–49

3.6 Interface Clocking Options .......................................................................................................................3–50

3.6.1 Master/Slave .........................................................................................................................................3–50

3.6.1.1 Master/Slave RS-422 or V.35 .......................................................................................................3–51

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3.6.1.1.1 Modem Settings (Master).......................................................................................................3–52

3.6.1.1.2 Modem Settings (Slave).........................................................................................................3–52

3.6.1.2 Master/Slave G.703 .......................................................................................................................3–53

3.6.1.3 Master/Slave X.21 .........................................................................................................................3–54

3.6.1.3.1 Modem Settings (Master).......................................................................................................3–54

3.6.1.3.2 Modem Settings (Slave).........................................................................................................3–54

3.6.1.4 Master/Slave External Station Clock.............................................................................................3–55

3.6.1.4.1 Modem Settings (Master).......................................................................................................3–55

3.6.1.4.2 Modem Settings (Slave).........................................................................................................3–55

3.6.2 Master/Master .......................................................................................................................................3–56

3.6.2.1 Master/Master (Customer Clock) ..................................................................................................3–56

3.6.2.1.1 Modem Settings (Master).......................................................................................................3–57

3.6.2.2 Master/Master (Station Clock) ......................................................................................................3–58

3.6.2.2.1 Modem Settings (Master).......................................................................................................3–59

CHAPTER 4. OPERATION........................................................................................ 4–1

4.1 Front Panel ...................................................................................................................................................4–2

4.1.1 LED Indicators........................................................................................................................................4–3

4.1.2 Controls ..................................................................................................................................................4–3

4.1.3 Menus and Options Overview ................................................................................................................4–4

4.1.4 Menu Explanations .................................................................................................................................4–9

4.1.4.1 Select Configuration........................................................................................................................4–9

4.1.4.2 Select Monitor ...............................................................................................................................4–15

4.1.4.3 Select Faults ..................................................................................................................................4–16

4.1.4.3.1 Modulator Faults (Mod_Flts).................................................................................................4–17

4.1.4.3.2 Demodulator/Decoder Faults (Dmd_Flts)..............................................................................4–17

4.1.4.3.3 Common Equipment Faults (CEq_Flts)................................................................................. 4–17

4.1.4.4 Select Stored Faults (StFaults) ......................................................................................................4–18

4.1.4.5 Select Utility..................................................................................................................................4–19

CHAPTER 5. THEORY OF OPERATION.................................................................. 5–1

5.1 Modulator ..................................................................................................................................................... 5–1

5.1.1 Specifications..........................................................................................................................................5–3

5.1.2 Theory of Operation ...............................................................................................................................5–5

5.2 Sequential Decoder/Demodulator Processor .............................................................................................5–7

5.2.1 Specification ...........................................................................................................................................5–8

5.2.2 Theory of Operation ...............................................................................................................................5–9

5.2.2.1 Demodulator Processor ...................................................................................................................5–9

5.2.2.2 Sequential Decoder........................................................................................................................5–10

5.2.2.2.1 Sequential Decoder BER Performance Specifications...........................................................5–12

5.3 Demodulator ...............................................................................................................................................5–16

5.3.1 Specifications........................................................................................................................................5–17

5.3.2 Theory of Operation .............................................................................................................................5–17

5.4 Reacquisition, Fast Acquisition, and Directed Sweep.............................................................................5–18

5.4.1 Reacquisition ........................................................................................................................................5–18

5.4.2 Fast Acquisition ....................................................................................................................................5–19

5.4.3 Directed Sweep.....................................................................................................................................5–20

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CHAPTER 6. MAINTENANCE................................................................................... 6–1

6.1 System Checkout ..........................................................................................................................................6–1

6.1.1 Modulator ...............................................................................................................................................6–1

6.1.2 Demodulator ........................................................................................................................................... 6–2

6.1.3 Test Points ..............................................................................................................................................6–8

6.1.3.1 Modulator ........................................................................................................................................6–8

6.1.3.2 Demodulator....................................................................................................................................6–9

6.1.3.3 Sequential Decoder/Demod Card ..................................................................................................6–10

6.2 Fault Isolation.............................................................................................................................................6–11

6.2.1 Modulator Faults (Mod_Flts Menu) ..................................................................................................... 6–11

6.2.2 Demodulator/Decoder Faults (Dmd_Flts Menu)..................................................................................6–12

6.2.3 Common Equipment Faults (CEq_Flts Menu) ..................................................................................... 6–14

6.3 Interface Fault Isolation ............................................................................................................................ 6–15

6.3.1 Transmit Faults (TX_INTF) .................................................................................................................6–15

6.3.2 Receive Faults (RX_INTF)...................................................................................................................6–16

6.4 Module Replacement .................................................................................................................................6–21

6.5 Module Identification.................................................................................................................................6–21

APPENDIX A. DATA RATES AND FILTERS............................................................A–1

A.1 Fixed Rate Filters ....................................................................................................................................... A–1

A.1.1 Data Rate Change Instructions.............................................................................................................. A–1

A.1.2 Hardware Configuration .......................................................................................................................A–5

A.2 Variable Rate Filters..................................................................................................................................A–6

A.2.1 Data Rate Change Instructions.............................................................................................................. A–6

A.2.2 Hardware Configuration .......................................................................................................................A–7

A.2.3 Utility ....................................................................................................................................................A–9

APPENDIX B. REMOTE CONTROL OPERATION ...................................................B–1

B.1 Standard Version........................................................................................................................................ B–1

B.1.1 General.................................................................................................................................................. B–2

B.1.2 Message Structure ................................................................................................................................. B–2

B.1.2.1 Start Character ...............................................................................................................................B–2

B.1.2.2 Device Address.............................................................................................................................. B–3

B.1.2.3 Command/Response ...................................................................................................................... B–4

B.1.2.4 End Character ................................................................................................................................B–4

B.1.3 Configuration Commands/Responses ................................................................................................... B–5

B.1.3.1 Set Modulator Frequency............................................................................................................... B–5

B.1.3.2 Set RF Output ................................................................................................................................ B–5

B.1.3.3 Set Demodulator Frequency ..........................................................................................................B–5

B.1.3.4 Set Modulator Power Offset .......................................................................................................... B–6

B.1.3.5 Set Modulator Output Power Level ............................................................................................... B–6

B.1.3.6 Modulator Rate .............................................................................................................................. B–7

B.1.3.6.1 Modulator Filter Rate Assignment ......................................................................................... B–7

B.1.3.6.2 Select Modulator Rate ............................................................................................................ B–8

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B.1.3.6.3 Select Modulator Rate Variable .............................................................................................B–8

B.1.3.7 Demodulator Rate.......................................................................................................................... B–9

B.1.3.7.1 Demodulator Filter Rate Assignment..................................................................................... B–9

B.1.3.7.2 Select Demodulator Rate...................................................................................................... B–10

B.1.3.7.3 Select Demodulator Rate Variable ....................................................................................... B–10

B.1.3.8 Scrambler Enable......................................................................................................................... B–10

B.1.3.9 Descrambler Enable..................................................................................................................... B–10

B.1.3.10 Differential Encoder Enable ......................................................................................................B–11

B.1.3.11 Transmit Clock .......................................................................................................................... B–11

B.1.3.12 Receive Clock............................................................................................................................ B–11

B.1.3.13 Baseband Loopback...................................................................................................................B–11

B.1.3.14 RF Loopback ............................................................................................................................. B–12

B.1.3.15 IF Loopback............................................................................................................................... B–12

B.1.3.16 Time of Day............................................................................................................................... B–12

B.1.3.17 Date............................................................................................................................................ B–13

B.1.3.18 Remote....................................................................................................................................... B–13

B.1.3.19 Clear Stored Faults .................................................................................................................... B–13

B.1.3.20 BER Threshold .......................................................................................................................... B–13

B.1.3.21 Sweep Reacquisition.................................................................................................................. B–14

B.1.3.22 Fast Acquisition Mode............................................................................................................... B–14

B.1.3.22.1 Sweep Center Frequency.................................................................................................... B–15

B.1.3.22.2 Sweep Width Range ........................................................................................................... B–15

B.1.3.22.3 Sweep Direction ................................................................................................................. B–16

B.1.3.23 Modem Operation Mode............................................................................................................ B–16

B.1.3.24 Buffer Control Mode ................................................................................................................. B–16

B.1.3.24.1 Buffer Clock....................................................................................................................... B–17

B.1.3.24.2 Interface Buffer Center....................................................................................................... B–17

B.1.3.24.3 Interface Buffer Size .......................................................................................................... B–17

B.1.4. Status Commands/Responses............................................................................................................. B–18

B.1.4.1 Configuration............................................................................................................................... B–18

B.1.4.1.1 Modulator/Coder Status ....................................................................................................... B–18

B.1.4.1.2 Modulator/Coder Program.................................................................................................... B–18

B.1.4.1.3 Demodulator/Decoder Configuration Status ........................................................................ B–19

B.1.4.1.4 Demodulator/Decoder Configuration Program .................................................................... B–20

B.1.4.2 Modem Faults Status (Summary) ................................................................................................ B–20

B.1.4.3 Modulator Status.......................................................................................................................... B–21

B.1.4.4 Demodulator Status...................................................................................................................... B–21

B.1.4.5 Common Equipment Status ......................................................................................................... B–22

B.1.4.6 Interface Receive Side Status ...................................................................................................... B–22

B.1.4.7 BER Status................................................................................................................................... B–23

B.1.4.7.1 Raw BER..............................................................................................................................B–23

B.1.4.7.2 Corrected BER ..................................................................................................................... B–23

B.1.4.8 E

Status.................................................................................................................................. B–24

b/N0

B.1.4.9 Modulator Rate Status ................................................................................................................. B–24

B.1.4.10 Demodulator Rate Status ........................................................................................................... B–24

B.1.4.11 Receive Signal Level Status ...................................................................................................... B–25

B.1.4.12 Current Sweep Value................................................................................................................. B–25

B.1.4.13 Stored Faults .............................................................................................................................. B–26

B.1.4.13.1 Modulator Stored Faults..................................................................................................... B–26

B.1.4.13.2 Demodulator Stored Faults................................................................................................. B–26

B.1.4.13.3 Common Equipment Stored Faults..................................................................................... B–27

B.1.4.13.4 Interface Receive Side Status Stored Faults ....................................................................... B–27

B.1.4.14 Bulk Consolidated Status........................................................................................................... B–28

B.1.4.15 Bulk Consolidated Analog Status .............................................................................................. B–30

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B.1.4.16 Bulk Consolidated Status Faults ................................................................................................ B–30

B.1.4.17 Change Status ............................................................................................................................B–31

B.1.4.18 Equipment Type......................................................................................................................... B–32

B.2 Asynchronous Overhead Interface Support Option ............................................................................. B–33

B.2.1 General................................................................................................................................................ B–33

B.2.2 Message Structure ............................................................................................................................... B–33

B.2.2.1 Start Character .............................................................................................................................B–34

B.2.2.2 Device Address............................................................................................................................ B–34

B.2.2.3 Command/Response .................................................................................................................... B–35

B.2.2.4 End Character ..............................................................................................................................B–35

B.2.3 Modulator Configuration Commands ................................................................................................. B–36

B.2.3.1 Set Modulator Frequency............................................................................................................. B–36

B.2.3.2 Set RF Output .............................................................................................................................. B–36

B.2.3.3 Set Modulator Power Offset ........................................................................................................ B–36

B.2.3.4 Set Modulator Output Power Level ............................................................................................. B–37

B.2.3.5 Modulator Rate ............................................................................................................................ B–38

B.2.3.5.1 Modulator Filter Rate Assignment ....................................................................................... B–38

B.2.3.5.2 Select Modulator Rate .......................................................................................................... B–39

B.2.3.5.3 Select Modulator Rate Variable ...........................................................................................B–39

B.2.3.6 Scrambler Enable......................................................................................................................... B–39

B.2.3.7 Differential Encoder Enable ........................................................................................................B–40

B.2.4 Demodulator Configuration Commands ............................................................................................. B–40

B.2.4.1 Set Demodulator Frequency ........................................................................................................B–40

B.2.4.2 Demodulator Rate........................................................................................................................ B–40

B.2.4.2.1 Demodulator Filter Rate Assignment................................................................................... B–41

B.2.4.2.2 Select Demodulator Rate...................................................................................................... B–41

B.2.4.2.3 Select Demodulator Rate Variable ....................................................................................... B–41

B.2.4.3 Descramble Enable ...................................................................................................................... B–42

B.2.4.4 RF Loopback ............................................................................................................................... B–42

B.2.4.5 IF Loopback................................................................................................................................. B–42

B.2.4.6 BER Threshold ............................................................................................................................ B–42

B.2.4.7 Sweep Reacquisition.................................................................................................................... B–43

B.2.4.8 Fast Acquisition Mode................................................................................................................. B–43

B.2.4.8.1 Sweep Center Frequency...................................................................................................... B–44

B.2.4.8.2 Sweep Width Range ............................................................................................................. B–44

B.2.4.8.3 Sweep Direction ................................................................................................................... B–45

B.2.5 Interface Configuration Commands.................................................................................................... B–45

B.2.5.1 Transmit Clock ............................................................................................................................ B–45

B.2.5.2 Buffer Clock ................................................................................................................................B–45

B.2.5.3 Receive Clock.............................................................................................................................. B–46

B.2.5.4 External Reference Frequency..................................................................................................... B–46

B.2.5.5 Interface Loopback ...................................................................................................................... B–46

B.2.5.6 Baseband Loopback.....................................................................................................................B–46

B.2.5.7 Interface Coding Format Transmit............................................................................................... B–47

B.2.5.8 Interface Coding Format Receive ................................................................................................ B–47

B.2.5.9 Interface Buffer Center ................................................................................................................ B–47

B.2.5.10 Interface Buffer Size.................................................................................................................. B–47

B.2.5.11 Transmit Overhead Baud Rate................................................................................................... B–48

B.2.5.12 Receive Overhead Baud Rate .................................................................................................... B–48

B.2.5.13 Overhead Channels Character Length ....................................................................................... B–48

B.2.5.14 Overhead Channels Stop Bits .................................................................................................... B–48

B.2.5.15 Overhead Channels Parity ......................................................................................................... B–49

B.2.5.16 Interface Substitution Pattern (Transmit 2047 Pattern) .............................................................B–49

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B.2.6 System Commands/Responses............................................................................................................ B–49

B.2.6.1 Time of Day.................................................................................................................................B–49

B.2.6.2 Date.............................................................................................................................................. B–50

B.2.6.3 Remote......................................................................................................................................... B–50

B.2.6.4 Clear Stored Faults ...................................................................................................................... B–50

B.2.6.5 Modem Operation Mode.............................................................................................................. B–51

B.2.7 Automatic Uplink Power Control (AUPC) Configuration Commands............................................... B–51

B.2.7.1 Local Modem AUPC Commands ................................................................................................ B–51

B.2.7.1.1 Local AUPC Enable ............................................................................................................. B–51

B.2.7.1.2 Nominal AUPC Power Level ............................................................................................... B–51

B.2.7.1.3 Maximum AUPC Power Limit............................................................................................. B–52

B.2.7.1.4 Minimum AUPC Power Limit .............................................................................................B–52

B.2.7.1.5 E

Target AUPC Set Point............................................................................................... B–52

b/N0

B.2.7.1.6 Maximum AUPC Tracking Rate .......................................................................................... B–52

B.2.7.1.7 AUPC Local Carrier Loss Action......................................................................................... B–53

B.2.7.1.8 AUPC Remote Carrier Loss Action .....................................................................................B–53

B.2.7.2 Remote Modem AUPC Commands............................................................................................. B–53

B.2.7.2.1 Remote AUPC Enable.......................................................................................................... B–53

B.2.7.2.2 Remote Interface Substitution Pattern (Transmit 2047 Pattern)........................................... B–54

B.2.7.2.3 Remote Interface Baseband Loopback................................................................................. B–54

B.2.7.2.4 Remote Interface Read Error Status (Received 2047 Pattern) .............................................B–54

B.2.8 Status Commands/Responses.............................................................................................................. B–55

B.2.8.1 Configuration Status .................................................................................................................... B–55

B.2.8.1.1 Modulator/Coder Configuration Status ................................................................................ B–55

B.2.8.1.2 Modulator/Coder Configuration Program ............................................................................ B–56

B.2.8.1.3 Demodulator/Decoder Configuration Status ........................................................................ B–57

B.2.8.1.4 Demodulator/Decoder Configuration Program .................................................................... B–58

B.2.8.1.5 Interface Configuration Status.............................................................................................. B–59

B.2.8.1.6 AUPC Configuration Status ................................................................................................. B–59

B.2.8.2 Modem Faults Status (Summary) ................................................................................................ B–60

B.2.8.3 Modulator Status.......................................................................................................................... B–60

B.2.8.4 Demodulator Status...................................................................................................................... B–60

B.2.8.5 Common Equipment Status ......................................................................................................... B–61

B.2.8.6 Interface Transmit Side Status..................................................................................................... B–61

B.2.8.7 Interface Receive Side Status ...................................................................................................... B–61

B.2.8.8 Bit Error Rate Status.................................................................................................................... B–62

B.2.8.8.1 Raw BER..............................................................................................................................B–62

B.2.8.8.2 Corrected BER ..................................................................................................................... B–62

B.2.8.9 E

............................................................................................................................................ B–63

b/N0

B.2.8.10 Modulator Rate .......................................................................................................................... B–63

B.2.8.11 Demodulator Rate...................................................................................................................... B–63

B.2.8.12 Receive Signal Level ................................................................................................................. B–64

B.2.8.13 Current Sweep Value................................................................................................................. B–64

B.2.8.14 Interface Buffer Fill Status ........................................................................................................ B–64

B.2.8.15 Interface Read Error Status........................................................................................................ B–64

B.2.8.16 Stored Faults .............................................................................................................................. B–65

B.2.8.16.1 Modulator Stored Faults..................................................................................................... B–65

B.2.8.16.2 Demodulator Stored Faults................................................................................................. B–65

B.2.8.16.3 Common Equipment Stored Faults..................................................................................... B–66

B.2.8.16.4 Interface Transmit Side Stored Faults ................................................................................ B–66

B.2.8.16.5 Interface Receive Side Stored Faults.................................................................................. B–66

B.2.8.17 Bulk Consolidated Status........................................................................................................... B–67

B.2.8.18 Bulk Consolidated Analog Status .............................................................................................. B–69

B.2.8.19 Bulk Consolidated Status Faults ................................................................................................ B–70

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Table of Contents SDM-650B Satellite Modem

B.2.8.20 Change Status ............................................................................................................................B–72

B.2.8.21 Equipment Type......................................................................................................................... B–72

B.2.8.22 Bulk Consolidated Status AUPC ............................................................................................... B–72

APPENDIX C. FIELD COMPATIBILITY ....................................................................C–1

C.1 SDM-650B Standard Modem....................................................................................................................C–1

C.2 SDM-650B Fairchild-Compatible Modem...............................................................................................C–2

C.3 SDM-650B Aydin Data Rate Modem ....................................................................................................... C–2

C.4 SDM-650B Comstream Modem................................................................................................................C–2

APPENDIX D. SOFTWARE CHANGE INSTRUCTIONS...........................................D–1

APPENDIX E. AGC INTERFACE .............................................................................. E–1

E.1 Connector Pinouts ...................................................................................................................................... E–2

E.2 Installation Instructions............................................................................................................................. E–2

E.2.1 Parts Required ....................................................................................................................................... E–2

E.2.2 Installation Procedure............................................................................................................................ E–3

APPENDIX F. ASYNCHRONOUS OVERHEAD CHANNEL UNIT ............................ F–1

F.1 Functional Description of ASYNC Overhead Channel Unit .................................................................. F–2

F.1.1 Terrestrial Interface ................................................................................................................................F–4

F.1.2 Multiplexer .............................................................................................................................................F–6

F.1.3 Demultiplexer .........................................................................................................................................F–6

F.1.4 Plesiochronous Buffer ............................................................................................................................F–7

F.2 ASYNC Interface Connector Pinouts ....................................................................................................... F–8

F.3 ASYNC Interface Specifications................................................................................................................ F–9

F.4 Functional Description of ASYNC Overhead Channel Unit with AUPC............................................ F–10

F.4.1 AUPC ...................................................................................................................................................F–10

F.4.2 Modem-to-Modem Channel for Remote M&C....................................................................................F–11

F.5 Front Panel Operation ............................................................................................................................. F–12

F.5.1 Menus and Options Overview ..............................................................................................................F–13

F.5.2 Menu Explanations...............................................................................................................................F–20

F.5.2.1 Select Configuration......................................................................................................................F–20

F.5.2.1.1 Configuration Modulator .......................................................................................................F–21

F.5.2.1.2 Configuration Demodulator...................................................................................................F–23

F.5.2.1.3 Configuration Interface..........................................................................................................F–25

F.5.2.1.4 Configuration AUPC .............................................................................................................F–28

F.5.2.2 Select Monitor...............................................................................................................................F–29

F.5.2.3 Select Faults ..................................................................................................................................F–30

xiv Rev. 5

SDM-650B Satellite Modem Table of Contents

F.5.2.3.1 Modulator Faults (Mod_FLTS) .............................................................................................F–31

F.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts) .............................................................................F–31

F.5.2.3.3 Common Equipment Faults (CEq_Flts).................................................................................F–31

F.5.2.3.4 Transmit Faults (TX_INTF) ..................................................................................................F–32

F.5.2.3.5 Receive Faults (RX_INTF)....................................................................................................F–32

F.5.2.4 Select Stored Faults (StFaults) ......................................................................................................F–33

F.5.2.5 Select Remote................................................................................................................................F–34

F.5.2.5.1 Remote Configuration............................................................................................................F–34

F.5.2.5.2 Remote Monitor.....................................................................................................................F–34

F.5.2.6 Select Utility..................................................................................................................................F–35

APPENDIX G. TROJAN INTERFACE ...................................................................... G–1

G.1 Functional Description ..............................................................................................................................G–1

G.2 Connector Pinouts......................................................................................................................................G–5

G.3 Specification................................................................................................................................................G–6

G.3.1 MIL-STD-188-114 Parameters.............................................................................................................G–6

G.3.2 Clock Synthesizer/Dejitter Circuit........................................................................................................G–6

G.3.3 Doppler Buffer Parameters ................................................................................................................... G–6

G.4 Configuration Guide..................................................................................................................................G–7

G.4.1 Modulator/Coder Defaults .................................................................................................................... G–7

G.4.2 Demodulator/Decoder Defaults (Dmd_Flts)......................................................................................... G–8

G.4.3 Interface Defaults.................................................................................................................................. G–8

G.5 Front Panel Operation...............................................................................................................................G–9

G.5.1 Menus and Options Overview ..............................................................................................................G–9

G.5.2 Menu Explanations .............................................................................................................................G–14

G.5.2.1 Select Configuration....................................................................................................................G–14

G.5.2.2 Select Monitor .............................................................................................................................G–14

G.5.2.3 Select Faults.................................................................................................................................G–14

G.5.2.3.1 Modulator Faults (Mod_Flts)...............................................................................................G–14

G.5.2.3.2 Demodulator/Decoder Faults (Dmd_Flts)............................................................................ G–14

G.5.2.3.3 Common Equipment Faults (CEq_Flts)...............................................................................G–14

G.5.2.4 Select Stored Faults (StFaults) ....................................................................................................G–15

G.5.2.5 Select Utility................................................................................................................................G–15

G.6 Remote Control Operation......................................................................................................................G–16

G.6.1 General................................................................................................................................................ G–16

G.6.1.1 Message Structure........................................................................................................................G–16

G.6.1.1.1 Start Character ......................................................................................................................G–17

G.6.1.1.2 Device Address ....................................................................................................................G–17

G.6.2 Command/Response............................................................................................................................G–18

G.6.3 End Character .....................................................................................................................................G–18

G.6.4 Configuration Commands/Responses.................................................................................................G–19

G.6.4.1 Modulator .................................................................................................................................... G–19

G.6.4.1.1 Set Modulator Frequency.....................................................................................................G–19

G.6.4.1.2 Set RF Output....................................................................................................................... G–19

G.6.4.1.3 Modulator Rate.....................................................................................................................G–20

G.6.4.1.3.1 Modulator Filter Rate Assignment................................................................................G–20

G.6.4.1.3.2 Select Modulator Rate...................................................................................................G–21

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Table of Contents SDM-650B Satellite Modem

G.6.4.1.3.3 Select Modulator Rate Variable.................................................................................... G–21

G.6.4.1.3.4 Set Modulator Power Offset ......................................................................................... G–21

G.6.4.1.3.5 Set Modulator Output Power Level .............................................................................. G–22

G.6.4.1.3.6 Scrambler Enable..........................................................................................................G–22

G.6.4.1.3.7 Differential Encoder Enable .........................................................................................G–22

G.6.4.2 Demodulator................................................................................................................................G–23

G.6.4.2.1 Set Demodulator Frequency................................................................................................. G–23

G.6.4.2.2 Demodulator Rate ................................................................................................................G–23

G.6.4.2.2.1 Demodulator Filter Rate Assignment ...........................................................................G–24

G.6.4.2.2.2 Select Demodulator Rate ..............................................................................................G–24

G.6.4.2.2.3 Select Demodulator Rate Variable................................................................................G–24

G.6.4.2.3 Descramble Enable...............................................................................................................G–25

G.6.4.2.4 IF Loopback ......................................................................................................................... G–25

G.6.4.2.5 RF Loopback........................................................................................................................G–25

G.6.4.2.6 Sweep Reacquisition ............................................................................................................ G–25

G.6.4.2.7 Fast Acquisition Mode ......................................................................................................... G–26

G.6.4.2.8 Sweep Center Frequency...................................................................................................... G–26

G.6.4.2.9 Sweep Width Range.............................................................................................................G–27

G.6.4.2.10 Sweep Direction .................................................................................................................G–27

G.6.4.2.11 Bit Error Rate Threshold....................................................................................................G–27

G.6.4.3 Interface/Doppler Buffer .............................................................................................................G–28

G.6.4.3.1 Baseband Loopback ............................................................................................................. G–28

G.6.4.3.2 Transmit Clock..................................................................................................................... G–28

G.6.4.3.3 Receive Clock ......................................................................................................................G–28

G.6.4.3.4 External Reference Frequency ............................................................................................. G–28

G.6.4.3.5 Interface Reference Clock....................................................................................................G–29

G.6.4.3.6 Interface Buffer Center ........................................................................................................G–29

G.6.4.3.7 Interface Buffer Depth .........................................................................................................G–29

G.6.4.4 System Commands/Responses .................................................................................................... G–30

G.6.4.4.1 Time of Day .........................................................................................................................G–30

G.6.4.4.2 Date ...................................................................................................................................... G–30

G.6.4.4.3 Remote .................................................................................................................................G–31

G.6.4.4.4 Clear Stored Faults...............................................................................................................G–31

G.6.4.4.5 Modem Operation Mode ......................................................................................................G–31

G.6.4.5 Status Commands/Responses ...................................................................................................... G–32

G.6.4.5.1 Configuration .......................................................................................................................G–32

G.6.4.5.1.1 Modulator/Coder Configuration Status.........................................................................G–32

G.6.4.5.1.2 Modulator/Coder Configuration Program.....................................................................G–33

G.6.4.5.1.3 Demodulator/Decoder Configuration Status.................................................................G–33

G.6.4.5.1.4 Demodulator/Decoder Configuration Program.............................................................G–34

G.6.4.5.1.5 Interface Configuration Status ......................................................................................G–34

G.6.4.5.2 Modem Faults Status (Summary)......................................................................................... G–35

G.6.4.5.3 Modulator Status .................................................................................................................. G–35

G.6.4.5.4 Demodulator Status..............................................................................................................G–35

G.6.4.5.5 Common Equipment Status..................................................................................................G–36

G.6.4.5.6 Bit Error Rate Status ............................................................................................................G–36

G.6.4.5.6.1 Raw BER ...................................................................................................................... G–36

G.6.4.5.6.2 Corrected BER..............................................................................................................G–37

G.6.4.5.7 E

.....................................................................................................................................G–37

b/N0

G.6.4.5.8 Modulator Rate.....................................................................................................................G–37

G.6.4.5.9 Demodulator Rate ................................................................................................................G–38

G.6.4.5.10 Receive Signal Level.......................................................................................................... G–38

G.6.4.5.11 Current Sweep Value .........................................................................................................G–38

G.6.4.5.12 Stored Faults ......................................................................................................................G–38

xvi Rev. 5

SDM-650B Satellite Modem Table of Contents

G.6.4.5.12.1 Modulator Stored Faults .............................................................................................G–39

G.6.4.5.12.2 Demodulator Stored Faults ......................................................................................... G–39

G.6.4.5.12.3 Common Equipment Stored Faults.............................................................................G–39

G.6.4.5.13 Bulk Consolidated Status ................................................................................................... G–40

G.6.4.5.14 Bulk Consolidated Analog Status ......................................................................................G–42

G.6.4.5.15 Bulk Consolidated Status Faults ........................................................................................G–42

G.6.4.5.16 Change Status..................................................................................................................... G–43

G.6.4.5.17 Equipment Type.................................................................................................................G–44

GLOSSARY ............................................................................................................... g–1

Rev. 5 xvii

Table of Contents SDM-650B Satellite Modem

Figures

Figure 1-1. SDM-650B....................................................................................................................................1–1

Figure 1-2. Satellite Communications System with an SDM-650B ................................................................ 1–2

Figure 1-3. Modular Construction ................................................................................................................... 1–4

Figure 1-4. Sequential Decoder BER Performance Curves (1/2 Rate)............................................................1–8

Figure 1-5. Sequential Decoder BER Performance Curves (3/4 Rate)............................................................1–9

Figure 1-6. Sequential Decoder BER Performance Curves (7/8 Rate)..........................................................1–10

Figure 1-7. Viterbi Decoder BER Performance Curves (1/2 Rate) ...............................................................1–11

Figure 1-8. SDM-650B Typical Output Spectrum ........................................................................................1–12

Figure 2-1. SDM-650B Rear Panel View........................................................................................................2–2

Figure 3-1. M&C Card ....................................................................................................................................3–2

Figure 3-2. RS-422 and MIL-STD-188-114 Interface Board..........................................................................3–7

Figure 3-3. RS-422 and MIL-STD-188-114 Block Diagram ..........................................................................3–8

Figure 3-4. V.35 Interface Card..................................................................................................................... 3–14

Figure 3-5. V.35 Interface Block Diagram ....................................................................................................3–15

Figure 3-6. DS-1 Interface Card .................................................................................................................... 3–20

Figure 3-7. DS-1 Interface Block Diagram....................................................................................................3–21

Figure 3-8. G.703 2048 kbit/s Interface Card................................................................................................3–24

Figure 3-9. G.703 2048 Interface Block Diagram .........................................................................................3–25

Figure 3-10. G.703 2048 kbit/s Interface Connector Board (Optional)......................................................... 3–28

Figure 3-11. G.703 2048 kbit/s Connector Board Schematic Diagram.........................................................3–29

Figure 3-12. Asynchronous Overhead Interface Block Diagram ..................................................................3–32

Figure 3-13. Asynchronous Overhead Jumpers.............................................................................................3–33

Figure 3-14. AS/3812 Doppler Buffer Daughter Card .................................................................................. 3–43

Figure 3-15. Clock Slip Diagram...................................................................................................................3–45

Figure 3-16. RS-422 or V.35 Master Slave Configuration............................................................................3–51

Figure 3-17. G.703 Master Slave Configuration ...........................................................................................3–53

Figure 3-18. X.21 Master/Slave Configuration .............................................................................................3–54

Figure 3-19. G.703 Master Slave Configuration ...........................................................................................3–55

Figure 3-20. Master/Master Customer Clock Configuration .........................................................................3–56

Figure 3-21. Master/Master Station Clock Configuration Diagram ..............................................................3–58

Figure 4-1. SDM-650B Front Panel View.......................................................................................................4–2

Figure 5-1. Modulator Block Diagram ............................................................................................................ 5–2

Figure 5-2. Modulator Output Spectral Occupancy.........................................................................................5–4

Figure 5-3. Decoder Block Diagram................................................................................................................5–7

Figure 5-4. Sequential Decoder BER Performance Curves (1/2 Rate)..........................................................5–13

Figure 5-5. Sequential Decoder BER Performance Curves (3/4 Rate)..........................................................5–14

Figure 5-6. Sequential Decoder BER Performance Curves (7/8 Rate)..........................................................5–15

Figure 5-7. Demodulator Block Diagram ......................................................................................................5–16

Figure 6-1. Typical Output Spectrum ..............................................................................................................6–4

Figure 6-2. Typical Output Spectrum ..............................................................................................................6–4

Figure 6-3. Typical Eye Pattern with Noise (Approximately 7.5 dB E

Figure 6-4. Typical Eye Pattern without Noise ...............................................................................................6–6

Figure 6-5. Typical Eye Constellation with Noise (Approximately 7.5 dB E

Figure 6-6. Typical Eye Constellation without Noise......................................................................................6–7

Figure 6-7. Modulator Test Points...................................................................................................................6–8

Figure 6-8. Demodulator Test Points...............................................................................................................6–9

Figure 6-9. Sequential Decoder/Demod Card Test Points.............................................................................6–10

Figure 6-10. Rear View Without Cover.........................................................................................................6–20

Figure A-1. Modulator Filter Card Change ....................................................................................................A–2

Figure A-2. Demodulator Filter Card Change ................................................................................................ A–4

) ...................................................6–6

b/N0

) .........................................6–7

b/N0

xviii Rev. 5

SDM-650B Satellite Modem Table of Contents

Figure E-1. Rear Panel View .......................................................................................................................... E–2

Figure E-2. Wiring Diagram........................................................................................................................... E–4

Figure E-3. AGC Adapter Board .................................................................................................................... E–5

Figure F-1. Asynchronous Overhead Interface Block Diagram ......................................................................F–3

Figure F-2. Asynchronous Overhead Interface Board.....................................................................................F–5

Figure G-1. Trojan Interface Block Diagram .................................................................................................G–2

Rev. 5 xix

Table of Contents SDM-650B Satellite Modem

Tables

Table 1-1. Operating Specifications ................................................................................................................1–5

Table 1-2. BER Performance Specifications ...................................................................................................1–7

Table 2-1. Rear Panel Connectors ...................................................................................................................2–2

Table 3-1. AS/0627-3 Rev. E Board Jumper Selection ................................................................................. 3–11

Table 3-2. AS/0627-2 Rev. E Board Jumper Selection ................................................................................. 3–17

Table 3-3. Equalizer Control .........................................................................................................................3–22

Table 3-4. G.703, 2048 kbit/s Interface Switch Configurations ....................................................................3–26

Table 3-5. G.703 2048 kbit/s Interface Connector Jumpers ..........................................................................3–29

Table 3-6. Asynchronous Overhead Jumper Table........................................................................................3–34

Table 3-7. Data Rate Jumper Table ...............................................................................................................3–34

Table 3-8. Jumper Selections......................................................................................................................... 3–41

Table 3-9. INTELSAT Delay Variations....................................................................................................... 3–41

Table 4-1. Main Front Panel Menu (Standard)................................................................................................4–4

Table 4-2. Select Configuration Menu ............................................................................................................4–5

Table 4-3. Select Monitor Menu......................................................................................................................4–6

Table 4-4. Select Faults Menu .........................................................................................................................4–6

Table 4-5. Select Stored Faults (StFaults) Menu .............................................................................................4–7

Table 4-6. Select Utility Menu.........................................................................................................................4–8

Table 6-1. EFData Conversion of (S+N)/N to S/N and E

Table 6-2. Programmable Data Rates for the Variable Rate SDM-650B Modem.........................................6–17

Table 6-3. EFData Part Numbers for SDM-650B Modules...........................................................................6–22

Table D-1. EFData M&C Viterbi Decoder Firmware ....................................................................................D–2

Table F-1. Asynchronous Overhead Jumpers..................................................................................................F–5

Table F-2. Data Rate Jumpers..........................................................................................................................F–5

Table F-3. Main Front Panel Menu with Asynchronous Overhead (with AUPC) ........................................F–13

Table F-4. Select Configuration Modulator Menu (with AUPC) ..................................................................F–13

Table F-5. Select Configuration Demodulator Menu (with AUPC)..............................................................F–14

Table F-6. Select Configuration Interface Menu (with AUPC).....................................................................F–15

Table F-7. Select Configuration AUPC Menu (with AUPC) ........................................................................F–16

Table F-8. Select Monitor Menu (with AUPC) .............................................................................................F–16

Table F-9. Select Faults Menu (with AUPC).................................................................................................F–17

Table F-10. Select Stored Faults (StFaults) Menu (with AUPC) ..................................................................F–18

Table F-11. Select Remote Menu (with AUPC)............................................................................................F–18

Table F-12. Select Utility Menu (with AUPC)..............................................................................................F–19

Table G-1. Main Front Panel Menu (Trojan Interface) ..................................................................................G–9

Table G-2. Select Configuration Modulator Menu....................................................................................... G–10

Table G-3. Select Configuration Demodulator Menu...................................................................................G–10

Table G-4. Select Configuration Interface Menu .........................................................................................G–11

Table G-5. Select Monitor Menu..................................................................................................................G–11

Table G-6. Select Faults (StFaults) Menu.....................................................................................................G–12

Table G-7. Select StFaults Menu..................................................................................................................G–13

Table G-8. Select Utility Menu..................................................................................................................... G–13

for Various Code Rates...................................6–5

b/N0

xx Rev. 5

Chapter 1.

INTRODUCTION

This manual describes the SDM-650B satellite modem, referred to in this document as “the modem” (Figure 1-1).

Figure 1-1. SDM-650B

Rev. 5 1–1

Introduction SDM-650B Satellite Modem

1.1 Purpose and Function

The modem is a high performance, full-duplex, Bi-Phase Shift Keying/Quadrature Phase Shift Keying (BPSK/QPSK), digital modulator/demodulator (modem), for Frequency Division Multiple Access (FDMA) satellite communication systems.

The modem provides an interface between Single Channel Per Carrier (SCPC) fixed-rate terminal equipment, having a data rate of 19.2 kbit/s to 3.584 Mbit/s.

The modem also provides an interface between IF converter equipment operating in a 50 to 90 MHz band, or 100 to 180 MHz band (Figure 1-2).

CUSTOMER

DATA

REMOTE

SERIAL

INTERFACE

FAULT

INDICATORS

DIGITAL

INTERFACE

SDM-650B

SATELLITE

ENCODER/

MODULATOR

MICRO- POWER

COMPUTER

DEMODULATOR/

SUPPLY

C POWER

RF EQUIPMENTDECODER

DATA MODEM

Figure 1-2. Satellite Communications System with an SDM-650B

TRANSMIT

RF EQUIPMENT

RECEIVE

ANTENNA

1–2 Rev. 5

SDM-650B Satellite Modem Introduction

The modem contains:

• Built-in scrambler/descrambler

• Differential encoder/decoder

• Transmit and receive frequency synthesizers

• Multi-rate Forward Error Correction (FEC) convolutional encoder-sequential

decoder (Viterbi K=7 is optional)

The modem provides high performance with:

• Narrow occupied bandwidth

• Automatic signal acquisition

• High flexibility

• Extensive online monitoring circuits

1.2 Description

The modem is a complete, self-contained unit in a standard 19” rack-mountable enclosure weighing approximately 25 lbs.

The modem is of modular construction (Figure 1-3).

The chassis assembly (with the front and rear panel) encloses several Printed Circuit Boards (PCBs). The backplane PCB is mounted on the chassis assembly, and contains receptacles for five plug-in PCBs.

Rev. 5 1–3

Introduction SDM-650B Satellite Modem

Figure 1-3. Modular Construction

Test points are located on the front board edge of the modulator, demodulator, and decoder PCBs. Refer to Section 6.1.4 for listings and diagrams of the test points.

All controls and indicators for operation of the modem are located on the front panel. For more information, refer to Chapter 4.

The chassis also contains the power supply; a fan is located on the rear panel.

The modem consists of the following assemblies:

Assembly Drawing #

Chassis with Power Supply AS/1099 PCB, M&C AS/0356 PCB, Modulator AS/0773-X PCB, Demodulator AS/0778-X PCB, Sequential Decoder AS/0365-X PCB, Front Panel Control Board AS/0361 PCB, Mother Board AS/0979-1 PCB, Digital Interface V.35 AS/0627-2 (Optional) PCB, Digital Interface DS1 AS/0569 (Optional) PCB, Digital Interface MIL-STD-188-114 AS/0627-3 (Optional) PCB, Doppler Buffer AS/3812 (Optional) PCB, Asynchronous Overhead Channel Unit AS/1311-X (Optional)

Note: X = various options available on the modulator, demodulator, and decoder boards.

1–4 Rev. 5

SDM-650B Satellite Modem Introduction

1.3 System Specification

Table 1-1 lists the operating specifications of the modem.

Table 1-1. Operating Specifications

System Specifications

Operating Frequency Range 50 to 90 MHz, or 100 to 180 MHz. Synthesized in

2.5 kHz steps.

Type of Modulation QPSK.

BPSK.

Operating Channel Spacing Less than 0.5 dB degradation operating with 2 adjacent

like channels each 10 dB higher at 1.3 times the

symbol rate or 75 kHz minimum. BER See Table 1-2. Digital Interface RS-422/-449.

V.35.

DS-1 STD.

G.703.

Others optional. Digital Data Rate:

Variable Rate Single Rate

Forward Error Correction Convolutional encoding with soft decision, sequential,

Data Scrambling Selectable.

Diagnostic Features RF Loopback.

Prime Power 90 to 132 VAC, or 180 to 264 VAC, 47 to 63 Hz.

Size 5.25” x 19.0” x 18.0” (3RU).

Additional Modulator Specifications

Output Power -5 to -30 dBm, adjustable in 0.5 dB steps.

Output Spurious and Harmonics -50 dBc in-band (50 to 90 MHz, or 100 to 180 MHz).

Output Impedance 75Ω. Output Return Loss 20 dB. Output Frequency Stability ± 10 PPM. Data Clock Source Internal or External. Internal Data Clock Stability ± 50 PPM.

19.2 to 3584 kbit/s configurable. Choice of up to four

pre-defined rates, or variable rate option.

19.2 to 48 kbit/s, 1/2 rate BPSK only.

19.2 to 2048 kbit/s.

19.2 to 3584 kbit/s.

2048 kbit/s maximum for 1/2 rate.

3072 kbit/s maximum for 3/4 rate.

3584 kbit/s maximum for 7/8 rate.

or K=7 Viterbi decoding.

CCITT V.35.

None.

IF Loopback.

Digital Data Loopback.

Fault Monitoring.

BER Monitoring.

Remote Control via Serial Port.

75W maximum, fused at 2A.

-48 VDC optional.

+5 to -15 dBm with high power option.

-40 dBc out-of-band.

Rev. 5 1–5

Introduction SDM-650B Satellite Modem

Additional Demodulator Specifications

Input Power:

Desired Carrier Composite

-30 to -55 dBm. +30 dB power within 20 MHz from desired carrier. +40 dB power outside of 20 MHz from desired carrier.

0 dBm maximum composite. Input Impedance 75Ω. Input Return Loss 20 dB. Carrier Acquisition Range ± 25 kHz minimum. Clock Acquisition Range ± 100 PPM.

Remote Control Specifications

Serial Interface RS-232-C, or RS-485. Baud Rate 300 to 9600 bit/s. Signals Controlled/Monitored Transmit Frequency.

Receive Frequency

Transmit Power.

Transmitter ON/OFF.

Data Rate Select.

RF Loopback.

IF Loopback.

Data Loopback.

Scrambler ON/OFF.

Descrambler ON/OFF.

Raw Error Rate.

Corrected BER.

Receive E

b/N0

TX Clock Internal/External.

RX Clock Normal/Invert.

Receive Signal Level.

Receive Carrier Detect.

Power Supply Voltages.

Stored Fault Status. Configuration Retention Will maintain current configuration for 30 days

minimum without power. Addressing Programmable to 1 of 255 possibilities. Address 0

reserved for global addressing. Local control of all remote functions included via push-button entry.

1–6 Rev. 5

+ 318 hidden pages

Comtech EF Data SDM-650B User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

About this Manual

Preface

Organization

Conventions Used in this Manual

Cautions and Warnings

References Used in this Manual

Military Standards

Trademarks

Related Documents

European EMC Directive

Reporting Comments or Suggestions Concerning this Manual

Customer Support

Table of Contents

INTRODUCTION

1.1 Purpose and Function

1.2 Description

1.3 System Specification