Adtran TRC4106 User Manual

TRACER 4106/4206

System Manual

12804106L1A TRACER 4106 System (Plan A)

12804106L1B TRACER 4106 System (Plan B)

12804206L1A TRACER 4206 System (Plan A)

12804206L1B TRACER 4206 System (Plan B)

612804206L1-1B

January 2003

Trademarks

Any brand names and product names included in this manual are trademarks, registered trademarks, or trade names of their respective holders.

To the Holder of the Manual

The contents of this manual are current as of the date of publication. ADTRAN reserves the right to change the contents without prior notice.

In no event will ADTRAN be liable for any special, incidental, or consequential damages or for commercial losses even if ADTRAN has been advised thereof as a result of issue of this publication.

901 Explorer Boulevard

P.O. Box 140000

Huntsville, AL 35814-4000

Phone: (256) 963-8000

Printed in U.S.A.

About this Manual

This manual provides a complete description of the TRACER 4106/4206 system and system software. The purpose of this manual is to provide the technician, system administrator, and manager with general and specific information related to the planning, installation, operation, and maintenance of the TRACER 4106/4206. This manual is arranged so that needed information can be quickly and easily found. The following is an overview of the contents.

Section 1 System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Provides managers with an overview of the TRACER 4106/4206 system.

Section 2 Microwave Path Engineering Basics . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Explains the basics of analyzing a wireless microwave link, or path. The significant parameters are defined, and several recommendations are offered.

Section 3 Engineering Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Provides information to assist network designers with incorporating the TRACER 4106/4206 system into their networks.

Section 4 Network Turnup Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Provides step-by-step instructions on how to install the TRACER 4106/4206 unit, determine the parameters for the system, install the network and option modules, and power up the system.

Section 5 User Interface Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Explains the terminal interface and provides a description for each of the menus available for the TRACER 4106/4206 system.

Section 6 Troubleshooting Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Provides helpful information for troubleshooting common configuration problems for the TRACER 4106/4206 system.

Revision History

This is the second issue of this manual.

Notes provide additional useful information.

Cautions signify information that could prevent service interruption.

Warnings provide information that could prevent damage to the equipment or endangerment to human life.

Safety Instructions

When using your telephone equipment, please follow these basic safety precautions to reduce the risk of fire, electrical shock, or personal injury:

1. Do not use this product near water, such as a bathtub, wash bowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool.

2. Avoid using a telephone (other than a cordless-type) during an electrical storm. There is a remote risk of shock from lightning.

3. Do not use the telephone to report a gas leak in the vicinity of the leak.

4. Use only the power cord, power supply, and/or batteries indicated in the manual. Do not dispose of batteries in a fire. They may explode. Check with local codes for special disposal instructions.

Save These Important Safety Instructions

Federal Communications Commission Radio Frequency Interference Statement

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio frequencies. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense.

Shielded cables must be used with this unit to ensure compliance with Class A FCC limits.

Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.

Radio Frequency Interface Statement

This equipment has been tested and found to comply with the limits for an intentional radiator, pursuant to Part 15, Subpart C of the FCC Rules. This equipment generates, uses, and can radiate radio frequency energy. If not installed and used in accordance with the instructions, it may cause interference to radio communications.

The limits are designed to provide reasonable protection against such interference in a residential situation. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause interference to radio or television reception, which can be determined by turning the equipment on and off, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna of the affected radio or television.

• Increase the separation between the equipment and the affected receiver.

• Connect the equipment and the affected receiver to power outlets on separate circuits.

• Consult the dealer or an experienced radio/TV technician for help.

Changes or modifications not expressly approved by ADTRAN could void the user’s authority to operate the equipment.

FCC Output Power Restrictions

The FCC does not require licensing to implement this device. License-free operation in the industrial, scientific, and medical band is documented in FCC Rules Part 15.247. It is the responsibility of the individuals designing and implementing the radio system to assure compliance with any pertinent FCC Rules and Regulations. This device must be professionally installed.

Exposure to Radio Frequency Fields

The TRACER 4106 is designed to operate at 2.4 GHz with 100 mW maximum transmit power. The TRACER 4206 is designed to operate at 5.8 GHz with 100 mW maximum transmit power.

This level of RF energy is below the Maximum Permissible Exposure (MPE) levels specified in FCC OET 65:97-01. The installation of high gain antenna equipment in the system configuration may create the opportunity for exposure to levels higher than recommended for the general population at a distance less than 15 feet (4.6 meter) from the center of the antenna. The following precautions must be taken during installation of this equipment:

• The installed antenna must not be located in a manner that allows exposure of the general population to the direct beam path of the antenna at a distance less than 15 feet (4.6 meters). Installation on towers, masts, or rooftops not accessible to the general population is recommended; or

• Mount the antenna in a manner that prevents any personnel from entering the area within 15 feet (4.6 meter) from the front of the antenna.

• It is recommended that the installer place radio frequency hazard warnings signs on the barrier that prevents access to the antenna.

• Prior to installing the antenna to the TRACER 4106/4206 output, make sure the power is adjusted to the settings specified in section 2 of this manual.

• During antenna installation, be sure that power to the TRACER equipment is turned off in order to prevent any energy presence on the coaxial connector.

• During installation and alignment of the antenna, do not stand in front of the antenna assembly.

• During installation and alignment of the antenna, do not handle or touch the front of the antenna.

These simple precautions must be taken to prevent general population and installation personnel from exposure to RF energy in excess of specified MPE levels.

Customer Service, Product Support Information, and Training

ADTRAN will repair and return this product if within five years from the date of shipment the product does not meet its published specification or the product fails while in service.

A return material authorization (RMA) is required prior to returning equipment to ADTRAN. For service, RMA requests, training, or more information, use the contact information given below.

Repair and Return

If you determine that a repair is needed, please contact our Customer and Product Service (CAPS) department to have an RMA number issued. CAPS should also be contacted to obtain information regarding equipment currently in house or possible fees associated with repair.

CAPS Department (256) 963-8722

Identify the RMA number clearly on the package (below address), and return to the following address:

ADTRAN Customer and Product Service 901 Explorer Blvd. (East Tower) Huntsville, Alabama 35806

RMA # _____________

Pre-Sales Inquiries and Applications Support

Your reseller should serve as the first point of contact for support. If additional pre-sales support is needed, the ADTRAN Support web site provides a variety of support services such as a searchable knowledge base, latest product documentation, application briefs, case studies, and a link to submit a question to an Applications Engineer. All of this, and more, is available at:

http://support.adtran.com

When needed, further pre-sales assistance is available by calling our Applications Engineering Department.

Applications Engineering (800) 615-1176

Post-Sale Support

Your reseller should serve as the first point of contact for support. If additional support is needed, the ADTRAN Support web site provides a variety of support services such as a searchable knowledge base, updated firmware releases, latest product documentation, service request ticket generation and trouble-shooting tools. All of this, and more, is available at:

http://support.adtran.com

When needed, further post-sales assistance is available by calling our Technical Support Center. Please have your unit serial number available when you call.

Technical Support (888) 4ADTRAN

Installation and Maintenance Support

The ADTRAN Custom Extended Services (ACES) program offers multiple types and levels of installation and maintenance services which allow you to choose the kind of assistance you need. This support is available at:

http://www.adtran.com/aces

For questions, call the ACES Help Desk.

ACES Help Desk (888) 874-ACES (2237)

Training

The Enterprise Network (EN) Technical Training Department offers training on our most popular products. These courses include overviews on product features and functions while covering applications of ADTRAN's product lines. ADTRAN provides a variety of training options, including customized training and courses taught at our facilities or at your site. For more information about training, please contact your Territory Manager or the Enterprise Training Coordinator.

Training Phone (800) 615-1176, ext. 7500

Training Fax (256) 963-6700

Training Email training@adtran.com

SYSTEM DESCRIPTION

This section of ADTRAN’s TRACER 4106/4206 System manual is designed for use by network engineers, planners, and designers for overview information about the TRACER 4106/4206.

It contains general information and describes physical and operational concepts, network relationships, provisioning, testing, alarm status, and system monitoring. This section should be used in conjunction with Section 3, Engineering Guidelines, of the system manual.

CONTENTS

System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Features and Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Configuration and Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Operational . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Section 1, System Description TRACER 4206 System Manual

1. SYSTEM OVERVIEW

The ADTRAN TRACER® 4106 and 4206 wireless systems provide four independent T1 circuits over a wireless link for up to 30 miles (line-of-sight path required). As authorized under Part 15.247 of the FCC Rules, the TRACER 4106 and 4206 operate license-free in the 2.4 GHz and 5.8 GHz Industrial, Scientific, and Medical (ISM) bands, respectively. These bands require no frequency coordination or licensing of end users.

For configuration and testing, the TRACER 4106/4206 provide the capability to control the remote system through a separate maintenance channel. The TRACER 4106/4206 has several built-in test capabilities including remote loopback. Complete configuration and performance data is available through menus accessed using a standard RS-232 terminal interface.

2. FEATURES AND BENEFITS

The following is a brief list of TRACER 4106/4206 features and benefits:

Configuration and Management

• Easy to use VT100 control port (RS-232 interface) for configuration and monitoring

• Remote configuration

Operational

• Four independent transparent T1 transmission paths, over digital microwave link

• No license required per FCC Rules Part 15.247

• Frequency: 2.400 to 2.4835 GHz (TRACER 4106) 5.725 to 5.850 GHz (TRACER 4206)

• Point-to-point, up to 30 miles

• 1-U high unit for easy rack-mounting

MICROWAVE PATH ENGINEERING BASICS

CONTENTS

Line-of-site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Decibels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Receiver Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Antenna Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Path Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Antenna Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Antenna Beam Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Fresnel Zones, Earth Curvature, & Antenna Heights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Coaxial Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Receiver Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Fade Margin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Path Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

FIGURES

Figure 1. Example Microwave Path with Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 2. Typical Antenna Beam Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

TABLES

Table 1. Antenna Gain for Given Dish Diameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 2. Path Loss for Given Path Lengths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 3. Minimum Antenna Height for Given Path Lengths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Table 4. Typical Coaxial Loss for Common Cable Types, per 100 ft. . . . . . . . . . . . . . . . . . . . . . . 20

Section 2, Microwave Path Engineering Basics TRACER 4206 System Manual

1. LINE-OF-SITE

The TRACER 4106 and 4206 systems are designed for operation in the license free 2.400 to 2.4835 GHz and 5.725 to 5.850 GHz Industrial, Scientific, and Medical (ISM) bands. Radio wave propagation in these bands exhibit microwave characteristics, which are ideally suited for point-to-point, line-of-sight communications. Line-of-sight essentially requires that the transmitting antenna and receiving antenna are able to “see” each other, and that the straight-line path between the two antennas is free of any obstructions, such as buildings, trees, mountains, and, in longer paths, even the curvature of the earth.

Point-to-Point Wireless communication from a single site to another

individual site. Contrast with point-to-multipoint

Line-of-Sight An unobstructed, direct path exists between the

transmitting and the receiving antennas.

2. DECIBELS

The received signal power equation is often expressed in a decibel (dB) format, which turns the power multiplication and division operations into addition and subtraction operations. In general, any quantity can be expressed in decibels. If the quantity (x) is a power level, the decibel equivalent is defined as

If the quantity x is referenced to a milliwatt (mW), then the decibel-milliwatt (dBm) is used instead of a generic decibel.

dBm

10 log10x()⋅

10 log

⋅



-------------



1mW

(dB)

(dBm)

3. RECEIVER POWER

The radio frequency (RF) signal power that is available at the input to the receiving TRACER 4106/4206 system is the next parameter of interest in analyzing a wireless path. The TRACER 4106/4206 has a maximum output power level of 100 mW, which is equivalent to 20 dBm. This output signal will be attenuated and distorted by various factors, all of which will degrade the original signal and affect the signal strength and quality as sensed by the receiving unit. A simplified power budget analysis is beneficial to perform after verifying a suitable line-of-sight path to determine if the microwave path is suitable, even for ideal, non-distorted signals.

The equation relating received signal power to the other microwave parameters is

PTGTGRλ



---------------------------

4π()2d2L

(watts, W)

TRACER 4206 System Manual Section 2, Microwave Path Engineering Basics

where the variables in the equation are defined as

received power (Watts) transmitted power (100 mW maximum for TRACER 4106/4206 - adjustable) transmit antenna gain receive antenna gain

λ carrier wavelength (c / ƒ) (meters) d path distance (meters) L other losses (RF coaxial cable, etc.)

The actual transmit and receive antenna gain values are strictly dependent upon the physical characteristics of the antennas installed for each link. Typical gains are between 20 and 40 dB. For example, a 4 foot diameter Parabolic dish has 34.2 dB of gain at 5.8 GHz. The carrier wavelength is the physical wavelength of the main RF carrier being used for communication, and is usually approximated at the center frequency of the band, which is 2441.75 or 5787.5 MHz. This gives a wavelength of 12.29 cm at 2441.75 MHz and

5.18 cm at 5787.5 MHz.

The FCC specifies the maximum transmitter power that may be used for antennae of a given gain. FCC rules Part 15, Subpart 247 allow for a maximum power of 1 watt (30 dBm) into antennae of a gain less than or equal to 6 dBi. At 2.4 GHz (TRACER 4106), the 1 watt maximum transmitter power must be reduced by 1 dB for every 3 dB of antenna gain over 6 dBi. Since the TRACER 4106 maximum transmit power is 100 milliwatts, only antennas with gains above 36 dBi (12 foot diameter parabolic dishes) require any reduction in transmit power. For the 5.8 GHz band (TRACER 4206), there is no reduction in transmitter output power required for antennae gains greater than 6 dBi.

The path distance is simply the physical distance between the transmit and receive antennas. For the TRACER 4106/4206 these distances can range up to 30 miles. The final parameter L incorporates all other signal power losses in the microwave link, most of which are caused by antenna feed.

4. ANTENNA GAIN

Best performance will result from the use of a parabolic dish antenna. Antenna gain is determined by the size of the dish, with typical features detailed below. Dish manufacturers will be able to supply gains for other types of antennas.

Table 1. Antenna Gain for Given Dish Diameters

Dish Diameter

(in feet)

2 21 28.5

4 27 34.2

6 31 37.5

8 33 40.7

10 35 42.5

12 37 44.2

Gain at 2.4 GHz (in dBi)

(TRACER 4106)

Gain at 5.8 GHz (in dBi)

(TRACER 4206)

Section 2, Microwave Path Engineering Basics TRACER 4206 System Manual

5. PATH LOSS

The expression

4πd



----------





4πdf



------------



(dB)

where

f carrier frequency (Hz)

λ carrier wavelength (c / f) (meters) d path distance (meters) c speed of light, free-space (meters)

is called the path loss, and increases rapidly as either path length increases or carrier wavelength decreases (which happens as the carrier frequency increases). So, longer microwave paths will naturally experience more path loss than shorter paths. Likewise, higher frequency microwave communication will experience more path loss than lower frequency microwave communication.

Table 2, tabulates path loss values for various path lengths for both 2.4 GHz and 5.8 GHz systems. Values not listed in the table can be interpolated from those listed.

Table 2. Path Loss for Given Path Lengths

Path Length

(miles)

1 104 112

2 110 118

3 114 121

4 116 124

5 118 126

10 124 132

15 128 135

20 130 138

25 132 140

30 134 141

35 135 143

Path Loss 2.4 GHz

(dB)

Path Loss 5.8 GHz

(dB)

When using decibel notation, the received power equation becomes

4πdf



PTGTGRL 20 · log





------------



(dBm)

PTGTGRL LP

(dBm)

TRACER 4206 System Manual Section 2, Microwave Path Engineering Basics

Where, in the second equation the path loss has been lumped into a single quantity, LP, as discussed previously. When using decibel notation, it is necessary that all quantities are individually converted to

decibels prior to performing addition and subtraction.

When d is expressed in miles and f in GHz, the path loss expression in decibels becomes

96.6 20 log10d() 20·log

f()⋅

(dB)

Figure 1 illustrates a wireless link containing all of the parameters previously discussed.

d, L

Figure 1. Example Microwave Path with Parameters

6. ANTENNA ALIGNMENT

With line-of-sight microwave communications, optimum system performance requires that the transmitting and receiving antennas are properly aligned. This will ensure maximum received signal power at each receiver. Antenna alignment must be achieved in both azimuth (along a horizontal plane) and elevation (along a vertical plane). A received signal strength indicator (RSSI) is used to aid the equipment installer in determining when alignment is maximized, by simply ensuring maximum RSSI. The RSSI indicator for the TRACER 4106/4206 system is provided through the VT100 terminal menus accessed through the RS-232 interface, and is presented as a series of bars indicating signal strength. More bars means more RSSI, which ensures more received signal strength and better link performance.

If the local system has acquired a useful signal from the remote system, then the remote TRACER 4106/4206 RSSI can also be viewed from the local TRACER 4106/4206 VT100 terminal menu interface.

An RSSI Test point is also provided on the front panel. The voltage (relative to the gnd test point) present on this test point represents a relative signal level of receive strength from the far end. The voltage at this test point can vary from approximatly 0 to greater than 4 Volts DC, with 0 Volts corresponding to no signal and 4 Volts or better to full signal strength.

Antenna Beam Patterns

Directly related to the subject of antenna alignment is the topic of antenna beam patterns. Antennas being used with the TRACER 4106/4206 system will have a particular beam shape determined in part by the physical construction and geometry of the antenna. The antenna beam patterns are characterized by a dominant main lobe, which is the preferred lobe to use for point-to-point communications, and several side

Section 2, Microwave Path Engineering Basics TRACER 4206 System Manual

lobes, as shown in Figure 2 on page 18. The antenna alignment step to setting up a microwave link is in fact steering the main lobes of both antennas until the main lobe of one transmitter is centered on the receiving element of the receiving antenna.

main lobe

side lobes

Figure 2. Typical Antenna Beam Pattern

Antennas are also designed to radiate RF energy efficiently for a specific range of frequencies. Please consult the data sheet for your particular antenna make and model to ensure that it is specified to operate in the 2400 MHz to 2483.5 MHz frequency band for TRACER 4106 models, and the 5725 MHz to 5850 MHz frequency band for TRACER 4206 models.

Fresnel Zones, Earth Curvature, & Antenna Heights

The Fresnel zones correspond to regions in the microwave path where reflections of the intended signal occur and combine in both constructive and destructive manners with the main signal, thereby either enhancing or reducing the net power at the receiver.

In general, the odd numbered Fresnel zones (1, 3, 5, ...) add constructively at the receiver, while the even numbered Fresnel zones (2, 4, 6, ...) add destructively at the receiver.

The first Fresnel zone corresponds to the main lobe, and must be at least 60% free of physical obstructions for the path calculations to be valid. Since the main lobe contains the vast majority of the microwave energy, this zone is typically used to determine proper antenna heights when placing antennas on towers or buildings.

The curvature of the Earth becomes a legitimate obstruction for path lengths of 7 miles or greater, and must also be accounted for when determining minimum antenna heights.

The aggregate expression for minimum antenna height that incorporates both the 60% first Fresnel zone and the Earth curvature is given by

h 72.1

----- 0.125d



(feet)

where f is in GHz and d is in miles.

Table 3 tabulates minimum antenna heights for given path lengths.

TRACER 4206 System Manual Section 2, Microwave Path Engineering Basics

Table 3. Minimum Antenna Height for Given Path Lengths

Path Length

(miles)

2 22 4 32 6 41

8 50 10 60 14 81 16 92 18 104 20 11 7 22 131 24 145 26 161 28 177 30 194 32 213 34 232 36 252

Min. Antenna Height

(ft)

7. COAXIAL CABLE

Coaxial cable will be required to attach the TRACER 4106/4206 to the antenna. The length of the cable will vary from a few feet to several feet, depending upon your application and the proximity of the TRACER 4106/4206 to the antenna.

Various grades of coaxial cable will work sufficiently well for connecting the TRACER 4106/4206 unit to the antenna. A low-loss coaxial cable is suggested to minimize cable losses. One end of the cable will require an N-type male connector (plug) to mate with the TRACER 4106/4206 unit. The other end of the coax will require a connector compatible with the antenna chosen for the installation, which is usually also an N-type male connector (plug). Additionally, it is recommended that both connectors on the coaxial cable be weatherproofed from the elements to prevent corrosion and electrical shorting.

Table 3 gives typical loss figures for some of the more common coaxial cable types, per 100 feet.

Section 2, Microwave Path Engineering Basics TRACER 4206 System Manual

Table 4. Typical Coaxial Loss for Common Cable Types, per 100 ft.

2.4 GHz Loss/100 ft. (in dB)

Cable Type

RG58 80 N/A

RG8 (air) 20 N/A

RG8 (foam) 9 N/A

1/4” Coax 5.91 11.36

3/8” Coax 5.76 9.65

1/2” Coax 3.83 6.49

5/8” Coax 2.98 4.90

7/8” Coax 2.2 N/A

1 1/4” Coax 1.62 N/A

1 5/8” Coax 1.41 N/A

5.8 GHz Elliptical Waveguide N/A 1.23

(TRACER 4106)

5.8 GHz Loss/100 ft. (in dB) (TRACER 4206)

In certain areas where lightning strikes are frequent, a lightning arrestor should be installed directly on the antenna coax. This will help protect the RF electronics in the downstream path from damaging voltages and currents, including the TRACER 4106/4206 unit.

8. RECEIVER SENSITIVITY

Receiver sensitivity is a value expressed in decibels referenced to one milliwatt (dBm) that corresponds to the minimum amount of signal power needed at the receiver to achieve a given bit error rate (BER). Receiver sensitivity is usually a negative number of decibels, and as such smaller receiver sensitivity (higher quantity negative numbers) is better for a given BER. Several factors affect receiver sensitivity, including the data bandwidth of the wireless link, and the amount of additional signal degradation

introduced in the receiver electronics. The receiver sensitivity of the TRACER 4106 is -93 dBm at 10

-6

error rate, while the receiver sensitivity of the TRACER 4206 is -90 dBm at 10

bit error rate.

Three software selectable band plans are provided for frequency agility, should an interferer be present nearby. Changing the 4106/4206 bandplan does not require additional components, or opening of the radio. See >TRACER System Configuration > RF Bandplan on page 47 for additional details.

-6

bit

TRACER 4206 System Manual Section 2, Microwave Path Engineering Basics

9. FADE MARGIN

Fade margin is a value indicating the amount of extra signal power available to the receiver to operate at a maximum bit error rate (BER). Higher levels of fade margin are better, and will protect the viability of the microwave link against signal fading. For most applications, 20 to 30 dB of fade margin should ensure a reliable link. Fade margin is simply the difference between the available signal power at the receiver and the receiver sensitivity, discussed previously:

FPRP

 PRGTGRL LP P

sens



sens

(dB)

10. PATH AVAILABILITY

The path availability of a wireless link is a metric that expresses the fractional amount of time a link is available over some fixed amount of time, and depends on several factors. Path availability is expressed as

A 1 2.5 10

6

×()abfd310

where the parameters are

a terrain factor b climate factor f carrier frequency (GHz) d path length (miles) F fade margin (dB)

The terrain factor is a quantity that compensates the link availability for different types of terrain. Generally speaking, the more smooth an area's terrain is, the less availability a wireless link running over that terrain will have, primarily due to multipath reflections. In contrast, secondary microwave signals will be randomly dispersed over rough terrain, and will not interfere with the main signal lobe as badly as in the smooth terrain case. The terrain factor values normally used are listed below:

F 10⁄

()[]100%×

(dB)

Terrain Terrain Factor Description

Smooth 4 water, flat desert

Average 1 moderate roughness

Mountainous 1/4 very rough, mountainous

+ 47 hidden pages

Adtran TRC4106 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

SYSTEM DESCRIPTION

1. SYSTEM OVERVIEW

2. FEATURES AND BENEFITS

Configuration and Management

Operational

MICROWAVE PATH ENGINEERING BASICS

1. LINE-OF-SITE

2. DECIBELS

3. RECEIVER POWER

4. ANTENNA GAIN

5. PATH LOSS

6. ANTENNA ALIGNMENT

Antenna Beam Patterns

Fresnel Zones, Earth Curvature, & Antenna Heights

7. COAXIAL CABLE

8. RECEIVER SENSITIVITY

9. FADE MARGIN

10. PATH AVAILABILITY