Spirent GSS7725 User Manual

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DGP01448AAA Issue 6-00 August 2017

Document status: APPROVED

GSS7725 INTERFERENCE GENERATOR USER MANUAL

PROPRIETARY INFORMATION

THE INFORMATION CONTAINED IN THIS DOCUMENT IS THE PROPERTY OF SPIRENT COMMUNICATIONS

PLC. EXCEPT AS SPECIFICALLY AUTHORISED IN WRITING BY SPIRENT COMMUNICATIONS PLC, THE

HOLDER OF THIS DOCUMENT SHALL KEEP ALL INFORMATION CONTAINED HEREIN CONFIDENTIAL AND

SHALL PROTECT SAME IN WHOLE OR IN PART FROM DISCLOSURE AND DISSEMINATION TO ALL THIRD

PARTIES TO THE SAME DEGREE IT PROTECTS ITS OWN CONFIDENTIAL INFORMATION.

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General

Contents

CHAPTER 1: GENERAL 1-3

1.1 This issue 1-3

1.2 Referenced documents 1-3

1.3 Copyright notices 1-3

1.4 Document format 1-4

1.5 Safety 1-4

CHAPTER 2: OVERVIEW 2-1

2.1 Technical Performance 2-1

2.2 Connectivity 2-1

2.3 Environmental & Safety 2-2

2.4 Operating parameters 2-2

2.5 Test Waveforms 2-3

CHAPTER 3: INTRODUCTION 3-1

3.1 Phases of operation 3-1

3.2 Nomenclature 3-1

CHAPTER 4: HARDWARE CONFIGURATION 4-1

4.1 External reference 4-1

4.2 Connectivity 4-1

4.3 GSS6300Mi 4-1

4.4 GSS6700 4-2

4.5 GSS7000 4-2

4.6 GSS9000 4-3

4.7 Power on sequence 4-3

4.8 Firewall Rules 4-3

CHAPTER 5: SCENARIO DEFINITION 5-1

5.1 Signal types 5-1

5.2 Use File 5-2

Interference Simulation File editor 5-3 Using the Interference Simulation File editor 5-4

5.3 Interactive mode 5-4

5.4 Interference commands 5-5

Comment 5-5 Interference Custom Waveform 7725 5-5 Interferer RF on/off 5-7 Interferer Level 5-8 Interferer Delta level 5-9 Operating mode with a User actions file and an interference file 5-9

5.5 Remote control interference commands 5-10

CHAPTER 6: INDEPENDENT REMOTE CONTROL 6-1

6.1 Configuration file 6-1

6.2 GSS7725 controller 6-1

6.3 Connecting to the controller 6-1

6.4 Remote command syntax 6-2

6.5 Remote commands 6-2

CHAPTER 7: CALIBRATION 7-1

7.1 Equipment required 7-1

7.2 Testing the output level 7-1

7.3 Calibrating the output level 7-2

TERMS & ABBREVIATIONS A-1

A.1 Simulator terms A-1

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A.2 Abbreviations and acronyms A-2

SPIRENT CUSTOMER SUPPORT B-1

INDEX AND LIST OF FIGURES AND TABLES C-1

INDEX C-1

LIST OF FIGURES C-3

LIST OF TABLES C-4

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General

Chapter 1: General

1.1 This issue

Note: “PosApp release” refers to the PosApp release for which this user manual is valid. Earlier releases of PosApp may have reduced functionality compared with this release. Spirent recommends you always use the latest PosApp release.

Issue Date

PosApp

release

Description

1-00

Nov 2016

5.07 SR02

Bugz:13332, Support for GSS7725

2-00

Feb 2017

6.00 SR04

Separate controller for GSS7725 V2.0 controller software

3-00

March 2017

6.00 SR04

Reference to sig_gen.txt, lservrc.txt and Cal_9

4-00

April 2017

6.01

Formatting and clarification

5-00

June 2017

6.01

Calibration procedure change

1.2 Referenced documents

a) DGP00686AAA SimGEN Software User Manual.

b) MS7725 GSS7725 Interference Generator Datasheet with Product Specification.

c) DGP00792AAA SimREMOTE User Manual.

1.3 Copyright notices

This document may use the following trademarks or registered trademarks:

Microsoft and Windows - trademarks or registered trademarks of Microsoft Corporation.

InstallShield - a registered trademark of InstallShield Software Corporation.

Alpha - a registered trademark of Hewlett Packard.

NovAtel - a registered trademark of NovAtel Inc.

MATLAB - a registered trademark of The Mathworks Inc.

All other company/product names are trademarks and/or service marks; or registered trademarks and/or service marks of the respective holders.

WinPcap copyright notice:

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

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GSS7725 Interference Generator User Manual

3. Neither the name of the Politecnico di Torino, CACE Technologies nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

1.4 Document format

Table 1-1 shows the formats used in this document.

Table 1-1 Formats used in this document

Format Description

Clear

Button name (with extra description to avoid ambiguity)

Edit

Menu item (with extra description to avoid ambiguity)

SimGEN.exe

Filename

Note: Insert the dongle

Important information

“Text”

Text entered from keyboard

Signal control - General

Title of dialog or window (with extra description to avoid ambiguity)

Signal Definition

Title of area within a dialog or window

code

Used for lines of code

code inverted

Used to enhance certain characters in lines of code

1.5 Safety

SAFETY WARNING

You must connect this signal generator to

mains earth (ground)

Completely isolate mains power by removing the plug from the mains socket, which should be close to the signal generator and readily accessible

NOTICE

Wait 10 seconds before re

-applying mains power to avoid blowing the mains

fuses

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Overview

Chapter 2: Overview

This document describes the GSS7725 Interference Simulation System. It details the configuration and operation of the GSS7725 using SimGEN and standalone use.

It is an addendum to reference a), the SimGEN User Manual.

2.1 Technical Performance

Table 2-1 GSS7725 Technical Performance

Parameter

GSS7725

Frequency Range

850MHz to 2.2 GHz

Frequency Resolution

100 Hz

Frequency Stability

< ± 1 ppm/yr, ± 1 ppm typical over 0 to +55°C

Bandwidth (3dB)

Up to 25 MHz

In band flatness

± 1.5 dB RSS

In band spurious

<-25 dBc

Harmonics

<-25 dBc

GNSS signal level

-130 dBm

GNSS signal level control

± 20 dB

GNSS signal level accuracy

± 1.0 dB RSS

I/S ratio relative to nominal GPS C/A signal level

0 to +110 dB

Interference level expressed as absolute power1

-130 to -20 dBm

Interference accuracy (CW) – I/S 10 to 110 dB

± 2.0 dB RSS

Interference level resolution

1 dB (nominal)

Note:

1) Specified maximum interferer level in ambient +20 to +30 °C. Typically the maximum level reduces by

0.2 dB/°C outside of this range.

2.2 Connectivity

Table 2-2 GSS7725 Connectivity

Port

Type

Detail

Description

RF OUTPUT

OUT

Coaxial Type ‘N’

Female

Front Panel

Provides the primary Combined GNSS

+ Interference signal output at specified levels. 50 ohm VSWR <1.25:1 (in band).

DC isolated1

GNSS IN

SMA

Provides connectivity to GNSS input

source. 50 ohm VSWR <1.25:1 (in band).

DC isolated1

10 MHz

Coaxial Type ‘BNC’

Socket

Allows the GSS7725 to be locked to an external reference of 10 MHz sine or

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GSS7725 Interference Generator User Manual

Port

Type

Detail

Description

Rear Panel

square wave. Recommended operation

1PPS

Coaxial Type ‘BNC’

Socket

Rear Panel

TTL level compatible 50 ohm

ETH0

IN/OUT

RJ-45

This is used for control of the

GSS7725 hardware or can be used for

passing through to a LAN.

ETH1

IN/OUT

RJ-45

This is used for control of the

GSS7725 hardware or can be used for

passing through to a LAN.

12V IN

12V DC input from an external power supply

Notes:

1) DC Isolation can withstand a maximum DC level of ±60V and reverse RF levels to a maximum of 1W.

2.3 Environmental & Safety

The GSS7725 is suitable for operation only in a typical office or laboratory environment.

Table 2-3 GSS7725 Environmental & Safety parameters

Property

Description

Temperature range

+15°C to +40°C The equipment employs forced-air cooling

Relative Humidity

75% max

Mechanical

Not exposed to vibration, shock or bump

Storage conditions

-40°C to +70°C

Power requirements

100 to 120 VAC, 50 to 60 Hz

220 to 240 VAC, 50 to 60 Hz

30W maximum

EMC

EMC Directive 2014/30/EU

EN 61326-1:2013 Electrical equipment for measurement, control

and laboratory use.

Safety

Low Voltage Directive (LVD) 2014/35/EU

IEC 60950-1:2005 (ED2) + A1:2009 + A2:2013 Information

technology equipment.

2.4 Operating parameters

Table 2-4 GSS7725 Operating parameters

Property

Description

OS for controller software

Windows 7 64 bit

IQ Input file sample rates

4, 16, 26, 51.5 & 120 MS/s (default 16 MS/s)

IQ input file format

Binary, 16 bit (2 byte) per sample, interleaved I&Q (I0Q0I1Q1I2Q2…) Big or little endian supported (default big endian)

Frequency

Can only be updated in non-transmit state.

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Property

Description

(default 1.57542 GHz)

Reference clock

Can only be updated in non-transmit state. (default internal)

Output sample rates

25 MS/s

Attenuator range

0 dB to 110 dB

Can be set/changed in transmit state with an update rate of 2 Hz

(default 0 dB)

Controller to PosApp IP

Address

192.168.5.30 (default PCIe card)

Controller to GSS7725 IP

addresses

192.168.10.1 (default motherboard)

2.5 Test Waveforms

Four test waves forms are contained within the install.

Table 2-5 GSS7725 Default Waveform Definitions

Waveform

Description

0x7FFF.bin

16 MS/s, big endian, CW signal, full power

0x4000.bin

16 MS/s, big endian, CW signal

test_full.bin

16 MS/s, big endian, swept frequency

tones_full_long.bin

16 MS/s, big endian, two tone test

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Chapter 3: Introduction

Spirent designed the GSS7725 to test Satellite Navigation receiver equipment in a simulated environment. The GSS7725 supports the playing of pre-canned IQ files that have been generated by either Spirent equipment or a third-party software. The interference is output at RF and optionally combined with the GNSS input from a Spirent signal generator. The output RF power of the GSS7725 can be controlled independently from the output RF power from a Spirent GNSS signal generator.

3.1 Phases of operation

This manual describes the operation of the GSS7725 in four separate phases:

Hardware Configuration

Describes the hardware interconnection of the GSS7725 and the interconnection to the software.

Scenario Definition

Guides you through defining the simulated interference environment.

Scenario Run-Time & Remote Control through SimGEN

Guides you through how to control the GSS7725 at run time while running a previously specified interference scenario.

Remote control

Guides you through how to take direct control of the GSS7725

3.2 Nomenclature

SimGEN and this document refer to various components using the Spirent nomenclature defined below.

SimGEN simulates one or more Vehicles, each Vehicle may have one or more Antennas mounted on it. Each Antenna corresponds to an RF port, either on the front or rear panel of the signal generator, or on the front panel of the GSS7725.

When you connect one (or more) GPS receivers to the RF output ports, the receiver functions as though it is connected to the simulated antenna mounted on the simulated vehicle.

The dual-output, GSS9000-series and GSS8000-series signal generators have two RF ports on the front panel, and can simulate two Vehicles, each with one antenna; or one Vehicle with two separate antennas. Alternatively, the single output signal generators may operate in L1/L2 mode, where the RF port produces an RF signal feeding a single antenna mounted on a single vehicle. You can combine up to four units to allow multiple vehicles/multiple antennas or multiple L1/L2 vehicle/antenna combinations.

The GSS7727 has a single RF input and a single combined RF output. A single GSS7725 may only be associated with one scenario antenna. Between scenarios, you can switch the GSS7725 between scenario antennas.

The collective name for the interference environment you require that incorporates the satellite constellation, vehicle motion, atmospheric effects and antenna properties is a Scenario.

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Chapter 4: Hardware configuration

Note:

1) This chapter describes the GSS7725 using single signal generator with one RF output

2) If the GSS7725 is being added to an existing Spirent GSS signal generator a new sig_gen.txt file is required to describe the new configuration as well as a new licence file lservrc.txt

3) For use with GSS9000 a Cal_9 will also be supplied. This file describes the path loss and delay through the GSS7725 and connecting cable.

4) For use with GSS7000 a Cal_7 will also be supplied. This file describes the path loss and delay through the GSS7725 and connecting cable.

4.1 External reference

Spirent recommends you lock your GSS7725 to an external 10 MHz reference and optionally a 1 PPS source, both these signals are output from a Spirent GSS signal generator.

Connect the external 10 MHz reference to the 10MHz port found on the back of the GSS7725.

4.2 Connectivity

The following sections show the interconnect diagrams for simple configurations of the GSS7725 with the Spirent GSS signal generators. Each diagram shows the GSS7725 at the top. The GSS7725 has its own controller separate from any controller required for the Spirent GSS signal generators

The new sig_gen.txt, lservrc.txt and (if required) Cal_9 or Cal_7 file should be loaded onto the PosApp controller required for the Spirent GSS signal generator or directly onto the Spirent GSS signal generator (GSS6300Mi and GSS7000). Spirent recommends that you first rename the old files so that they can be reused if returning to the original configuration.

The sig_gen.txt and lservrc.txt should be loaded to “D:\posapp\conf” (GSS7000, GSS9000) or

“C:\\Spirent Communications\Positioning Application”

If required the Cal_9 or Cal_7 file should be loaded to “D:\posapp\conf\system data\”

Wide Area Network (WAN) connections with internet access are required for Spirent Global Service team to provide remote support.

4.3 GSS6300Mi

WAN

Figure 1 GSS6300Mi & GSS7725 Hardware Connectivity

GSS7725 Controller

Ethernet

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4.4 GSS6700

4.5 GSS7000

Figure 2 GSS6700 & GSS7725 Hardware Connectivity

Figure 3 GSS7000 & GSS7725 Hardware Connectivity

GSS7725 Controller

GSS6700 Controller

Ethernet

GSS7725 Controller

WAN

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4.6 GSS9000

4.7 Power on sequence

To prevent communication errors the configuration should be powered on in the following sequence

1. GSS7725

2. GSS7725 controller PC

3. Spirent GSS signal generator

4. Any additional controller (e.g. “C50R” or GSS6700 controller)

If the GSS7725 controller PC is turned off or disconnected, then SimGEN will give the following error either immediately or the next time a scenario is started.

Fatal: Unable to connect to GSS7725 controller PC, check h/w is attached and software/scripts are running

If this error is seen check the Ethernet connections and if necessary re-power the GSS7725 controller. If the error is still seen you will need to power cycle the Spirent GSS signal generator and any additional controller.

4.8 Firewall Rules

The GSS7725 controller assumes that the Spirent GSS signal generator or controller communicates using port 13100 using the following static IP addresses

1. GSS7725 controller PC 192.168.5.30

2. Spirent GSS signal generator / controller 192.168.5.98

The windows firewall has rules set to allow this communication. If the user wishes to use different IP addresses then the firewall rules will need to be edited to match the new address.

Figure 4 GSS9000 & GSS7725 Hardware Connectivity

GSS7725 Controller

GSS9000 Controller “C50R”

WAN

Ethernet

10Mhz

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Chapter 5: Scenario Definition

This chapter guides you through specifying and using the GSS7725 within SimGEN.

5.1 Signal types

SimGEN specifies individual signal types for each antenna.

In the Scenario contents window of SimGEN, expand the vehicle and then expand the antenna. Next, select Signal Types: and either: right-click and select Edit, or double-click Signal Types: to show the Antenna Signal Types dialog, see Figure 5.

Figure 5 Antenna Signal Types dialog

Select the signal type you want to use.

After you have clicked OK, you may see the message "Incompatible h/w" appearing in the bottom right hand corner of the SimGEN window. The most likely cause for this error message is that the requested hardware is unavailable for that antenna. For example, you may be trying to select interference on antenna 2 when interference, as defined by the currently selected hardware configuration, is only available on antenna 1.

After you have selected Antenna Signal Types - Interference, you must specify the GSS7725 operating mode from:

a) Use File (see Section 5.2).

In Use File, the interference source uses an interference file whose parameters you define using the Interference Simulation File editor.

b) Interactive (see Section 5.3).

In interactive mode you use SimGEN to modify the interference power in real-time.

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5.2 Use File

Notes:

1) The Interference dialog is only available after selecting Interference in Antenna Signal Types,

see Figure 5.

2) If an *.itf file is present and selected within the scenario, SimGEN defaults to using this

interference file.

Interference files use the extension *.itf. In the Scenario contents window, under each antenna, highlight Interference file: see Figure 6, which shows the default filename default_v1-0.itf.

Figure 6 Scenario tree

Either click Select to select an existing file from the Select File dialog (shown in Figure 7) or create a new file by clicking New.

Then set SimGEN to use the interference file you specify by selecting the checkbox in the scenario tree.

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Figure 7 Select File dialog

Interference Simulation File editor

Note: Each Interference command is Interferer channel specific, so when associating an existing *.itf file with an antenna, it is important to ensure that the Interferer channel is available on that antenna.

The Interference Simulation File editor lets you view or edit the interference characteristics for all Interference channels associated with a given antenna. After selecting an existing file or opening a new file, you can then open the Interference Simulation File editor, seeFigure 8, by double-clicking on Vehicle - Antenna_n - Options - Interference file in the Scenario Contents window.

Figure 8 Interference Simulation File editor

You must specify the Interference commands for each Interference channel as a time ordered list. 0 00:00:00 indicates that the action specified will take place at the start time of the scenario, 0 00:00:10 will take place 10 seconds into the scenario, and so on.

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The leading zero is the number of days into the scenario.

There are four menus:

File

use to save or rename the file and to exit the editor

Edit

use to select commands listed in the window, and to Cut and Paste, or Delete

them. Use the Cut and Paste options to move selected commands in the list. The Cut option cuts all highlighted commands, the Paste option pastes commands after the currently selected command. Use the Edit menu to Undo or Redo actions

Tools

Check all - use to check if the entire list of commands is in a time-ordered sequence

Help

use to obtain on-line help.

Using the Interference Simulation File editor

Note: When you start to edit an existing file, the editor selects the first action.

The file editor is identical to the list editor in SimGEN see reference a).

5.3 Interactive mode

You can interactively control an interference source by first de-selecting or removing the relevant interference file from the Scenario contents window. Then, click on View - Interactive Interference

Window (or use the SimGEN Toolbar button see Figure 9, which enables the interference controls.

Once the scenario is running, you can control the various parameters of the GSS7725 during the scenario run. The only parameter that can be changed immediately without briefly interrupting the interference RF of the GSS7725 is the power level (note that the GNSS RF path will not be interrupted). Other changes you make in the Interference dialog propagate as commands to the GSS7725 when you click “Update CWI”. These commands mirror the Interference commands in section 5.4.

Figure 9 Interference Window

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5.4 Interference commands

Note: For all commands that include Level and Custom Waveform parameters, select Check so that SimGEN determines if:

(Level + Reference Level) is less than -130.0 dBm

(Level + Reference Level) exceeds -20.0 dBm

You can apply interference commands using an Interference Simulation File (*.itf) (double-click Vehicle - Antenna_n - Options - Interference file) or dynamically through an Interactive Interference dialog.

In most dialogs, you must enter the Action time in days and hh:mm:ss.

All GSS7725 commands persist until countermanded by another command in the same category.

Click on File - Save as to save the Interference Simulation File. Type a name for the file. The file name you use appears in the Scenario tree next to Options - Interference file. By default, this file is stored in the scenario folder.

Comment

Comments have no impact on functionality of the Interference channel.

Use this command Figure 10, to insert comments you type in the Comments area into the interference simulation file.

Figure 10 Command type - Comment

Interference Custom Waveform 7725

Use this command see Figure 11, to setup the GSS7725 to output the IQ data as RF at the given sample rate, frequency and power.

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Figure 11 Command type - Interference Custom Waveform 7725

Action time

Set the days and time into the scenario you want to apply the Command type

Vehicle Antenna

Vehicle number for the command, default 1 Antenna number for the command, default 1

Channel

The interference channel number. Default: 1.

RF on

If this is ticked then when all the parameters have been set, turn on the RF output of the interference.

Check level

Selected: (default) Enables “Invalid power” checking. SimGEN

determines if Level+Reference Level exceeds -20 dBm and prevents entry of Level and Reference Level after clicking Deselected: SimGEN allows entry of any value of Level+Reference Level as determined by the total ranges of Level and Reference Level

Notes:

1) Select Check so that SimGEN determines if: (Level + Reference Level) is less than -130.0 dBm

(Level + Reference Level) exceeds -20.0 dBm

Level

Power level from reference -120 dBm

Range: 0 to 100 Step size: 1 dB Interference Power (dBm) = (Reference Level + Level)

Reference level

Type the reference level you want to use.

Default -130 dBm

Note: In Interference Fixed Level Mode and GPS Fixed Level Mode,

when you set Reference Level equal to the GPS received signal Reference Level, the data entered in Level directly equates to the

J/S ratio.

Centre frequency

Centre frequency that the IQ signal is to be produced around, default is L1 (1575.42 MHz)

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File

The name of the input IQ file that exists within the directory: <path_to_posapp>/GSS7725/waveforms The dropdown updates to the files present within the above directory with

the extensions .waveform or .bin

The format of the file should be, binary, 16 bit (2 byte) per sample,

interleaved I&Q (I0Q0I1Q1I2Q2…), big or little endian.

File sample frequency

The sample rate of the input File above, this can be selected as one of the following:

4 MS/s 16 MS/s 26 MS/s

51.1 MS/s 120 MS/s The default is 4 MS/s

File output frequency

The output sample frequency. The input file IQ will be up/down sampled using interpolation to the output sample frequency 25 MS/s.

The output sample rate achievable is reliant upon the specification of the controller machine that the GSS7725 controller software is running upon. i.e. dedicated Ethernet with no other traffic, number and clock speed of CPU cores, SSD vs HDD.

Reference clock

The internal reference clock has a frequency stability of 2.5 ppm. The clock frequency stability can be increased by setting this value to “External” and connecting the 10 MHz and 1 PPS from the GNSS signal generator to the back of the GSS7725.

The default is Internal.

File endianness

The endianness of the input IQ file. This can be set to Big or Little. Big implies that the first byte of data for each sample contains is the most significant. Little implies that the first byte of data for each sample contains the least significant.

Interferer RF on/off

Note: Specifying a customer waveform may also set the On/Off state of the Interference channel.

Use this command see Figure 12, to specify periods when the interference source is On at the Action time you enter.

Figure 12 Command type – Interferer RF on/off

Action time

Set the days and time into the scenario you want to apply the Command type

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Vehicle Antenna

Vehicle number for the command, default 1 Antenna number for the command, default 1

Channel

The interference channel number, default: 1

RF on

Selected (default): Set the interference source RF power on at the

Action time.

Deselected: Turn RF power off

Interferer Level

Note: Level is relative to a reference level:

Interference Power (dBm) = (Reference Level + Level)

Use this command see Figure 13, to change the absolute interferer signal level, at the Action time you enter.

Figure 13 Command type – Interferer Level

Action time

Set the days and time into the scenario you want to apply the Command type

Vehicle Antenna

Vehicle number for the command, default 1 Antenna number for the command, default 1

Channel

The interference channel number, default: 1

Level

Power level from reference -130 dBm

Range: 0 to 110 Step size: 1 dB

Interference Power (dBm) = (Reference Level + Level)

Check

Selected: (default) Enables “Invalid power” checking. SimGEN determines if

Level+Reference Level exceeds -20 dBm and prevents entry of Level and Reference Level after clicking Deselected: SimGEN allows entry of any value of Level+Reference Level as determined by the total ranges of Level and Reference Level

Notes:

1) Select Check so that SimGEN determines if: (Level + Reference Level) is less than -130.0 dBm (Level + Reference Level) exceeds -20.0 dBm

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Reference level

Type the reference level you want to use.

Default -130 dBm

Note: In Interference Fixed Level Mode and GPS Fixed Level Mode, when

you set Reference Level equal to the GPS received signal Reference Level,

the data entered in Level directly equates to the J/S ratio.

Interferer Delta level

Note: Delta level does not specify an absolute interferer signal level, only the value by which the current level is incremented or decremented.

Use this command see Figure 14, to specify an Increment (in dB) in interferer signal level at the Action time you enter.

Figure 14 Command type – Interfere Delta level

Action time

Set the days and time into the scenario you want to apply the Command type

Vehicle Antenna

Vehicle number for the command, default 1 Antenna number for the command, default 1

Channel

The interference channel number, default: 1

Increment

Type the amount by which you want to increment the interferer signal level

from the value set in a previous command. Range: 0 to 110

Step size: 1 dB

Operating mode with a User actions file and an interference file

See reference a) for details on the User actions file.

Table 5-1 details the mode of operation if a User action file (*.act) and an interference file (*.itf) are present in a scenario.

Table 5-1 Mode of operation with a user action file and an interference file

User action file

(*.act)

Interference file

(*.itf)

Mode of operation

none

Interactive interference mode

none

present

Replays the interference file commands

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User action file

(*.act)

Interference file

(*.itf)

Mode of operation

present

(contains interferer

commands)

none Replays the User actions file commands

present

(contains interferer

commands)

present

Replays both User action file commands AND interference file commands

present

(does not contain

interferer commands)

none

Interactive interference mode (the User actions file does not affect the interactive interference mode)

present

(does not contain

interferer commands)

present Replays the interference file commands

5.5 Remote control interference commands

Interference commands can be actioned remotely. Reference b) outlines the syntax for sending remote interference commands to SimGEN to operate the GSS7725. The remote commands are also briefly outlined below for convenience.

Table 5-2 GSS7725 SimGEN remote commands

Command

Description

<timestamp>, Custom Waveform 7725, <vehicle>, <antenna>, <channel>, <reference_level>, <level>, <check_level>, <file_name>, <centre_frequency_hz>, <sample_frequency_mhz>, <target_frequency_mhz>, <clock_type>, <endianness>, <rf_on_off>

Describes the waveform file to be output and optionally also turns on

the RF. An example would be:

00:00:10, Custom Waveform 7725, 1, 1, 1, -130, 50, on, “0x4000.bin”, 1.57542e+009, 4, 12.5, External, Big, on

This would issue a command at 10 seconds in to the scenario run for vehicle 1, antenna 1, channel 1 using the IQ file “0x4000.bin” it would output an RF signal at L1, at -80 dBm, using a target sample rate of

12.5 MS/s and expecting the IQ file to be stored at the 4 MS/s sample rate.

Where:

::= time in to run specified by: [d] hh:mm:ss

::= integer starting at 1

::= integer starting at 1

::= integer starting at 1

<reference_level>

::= integer in dB i.e. -130

<level>

::= integer in dB

level above reference i.e. 110 would set the

level to -20 dBm, -130 + 110 = -20

<check_level>

::= “on” | “off”

<file_name>

::= quoted string i.e. “0x4000.bin”

<centre_frequency_hz>

::= integer or scientific representation of

centre

Frequency i.e. 1.57542e+009

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Command

Description

<sample_frequency_mhz>

::= float in MHz which must be one of the specified values (see 0)

<target_frequency_mhz>

::= float in MHz which must be one of the Specified values (see 0)

<clock_type>

::= “Internal” | “External”

::= “Big” | “Little”

<rf_on_off>

::= “on” | “off”

<timestamp>, Level, <vehicle>, <antenna>, <channel>, <reference_level>, <level>

Adjust the level of the current RF IQ file being played

An example would be:

00:01:00, Level, 1, 1, 1, -130, 110

This would issue a command at 1 minute in to the scenario run for vehicle 1, antenna 1, channel 1 and would adjust the RF signal level of the interference signal to be at -20 dBm for the current loaded/played IQ data.

Where:

::= time in to run specified by: [d] hh:mm:ss

::= integer starting at 1

::= integer starting at 1

::= integer starting at 1

<reference_level>

::= integer in dB i.e. -130

<level>

::= integer in dB

level above reference i.e. 110 would set the

level to -20 dBm, -130 + 110 = -20

<timestamp>, Delta Level, <vehicle>, <antenna>, <channel>, <delta>

Adjust the level of the current RF IQ file being played

An example would be:

01:01:00, Delta Level, 1, 1, 1, -13

This would issue a command at 1 hour and 1 minute in to the scenario run for vehicle 1, antenna 1, channel 1 and would adjust the RF signal level. If the previous level was -20 dBm then the adjustment of -13 would make the signal power output of the GSS7725 be -37 dBm for the current loaded/played IQ data.

Where:

::= time in to run specified by: [d] hh:mm:ss

::= integer starting at 1

::= integer starting at 1

::= integer starting at 1

<delta>

::= integer in dB i.e. -13

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Command

Description

Adjust the level of the current RF IQ file being played

An example would be:

1 00:10:00, RF on/off, 1, 1, 1, off

This would issue a command at 1 day and 10 minute in to the scenario run for vehicle 1, antenna 1, channel 1 and would turn the current RF output to off.

Where:

::= time in to run specified by: [d] hh:mm:ss

::= integer starting at 1

::= integer starting at 1

::= integer starting at 1

<rf_on_off>

::= “on” | “off”

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Chapter 6: Independent Remote Control

As well as using the GSS7725 as part of a SimGEN scenario and controlling it through the SimGEN remote interface, the GSS7725 can be used standalone as an IQ to RF player. To do this the GSS7725 must be commanded via its remote-control interface. Note that the GSS7725 controller software provides the remote interface.

6.1 Configuration file

The configuration file “remote.conf” is held within “C:\Program Files\Spirent Communications\Positioning Application\GSS7725\etc” of the GSS7725 controller.

Table 6-1 GSS7725 configuration file parameters

Parameter

Description

Comment

ip_port

The GSS7725 listening port. This should not be changed if using with

SimGEN or PT TestBench.

(default 13100)

processing_max_size

Max size (bytes) for input file to be processed. (default 200000000)

waveform_local_fname

Local copy file name of re-sampled input file. (default "WFormLocalCopy.bin")

prescaling_factor

Scales file before re-sampling (floating point)

1.0 = no scaling

2.0 = half amplitude (default)

calibration_samples_power

Samples power of the calibration signal (average I^2+Q^2) (default 536870912)

calibration_table_fname

Calibration table filename (.csv, vertical table) (default " CalibrationTable_UsrpEthAtt.csv")

target_power_output_dBm

Desired GSS7725 power output (shall be compatible with calibration) (default -19)

6.2 GSS7725 controller

The GSS7725 controller software is held in “C:\Program Files\Spirent Communications\Positioning Application\GSS7725\bin\ GSS7725_Remote_Controller64.img”. The GSS7725 controller software

automatically boots on power-up and launches the remote interface.

The controller has two pre-configured IP ports, both on static IP addresses

192.168. 9. 1 for connection to the GSS7725 hardware (9 network)

192.168. 5. 30 for connection to the Spirent GSS signal generators and direct remote control

(5 network)

For multiple GSS7725 each should be given its own unique (5 network) address.

6.3 Connecting to the controller

The GSS7725 controller will open a TCP/IP port at the given port address that is defined within the “remote.conf” file (see 6.1). Shown below is a Python example connecting to the GSS7725 controller from another PC that is connected to the same (5 network) as the GSS7725 controller. Note that the script assumes the default port and IP address are being used.

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import socket sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.connect(('192.168.5.30', 13100))

6.4 Remote command syntax

The GSS7725 controller accepts the standard command syntax for programming instruments (SCPI). The full syntax of the commands should be used. Every command apart from “:STATus” returns a standard command return value.

Table 6-2 GSS7725 full command syntax

Command

Syntax

:OUTput:STArt

Correct

:OUT:STA

Incorrect (bad)

Table 6-3 GSS7725 standard command return value

Value

Meaning

-1

Malformed, impossible

-2

Cannot process due to current status

-3

Cannot be executed (e.g. the required data or hardware is missing)

All commands take a finite time to process. A command such as setting the IQ file can take a number of seconds to process due to the conversion from the file sample rate to the required output sample rate. The command “:STATus” can be used to retrieve the current state of the controller. A return results of “PROCESSING” means that the last command is still being processed and no more commands can be processed at this time.

6.5 Remote commands

Table 6-4 GSS7725 remote commands

Command

Description

:FREQ:CARRier <value>

Set carrier frequency

Where <value> is an integer in Hz Range 50000000 to 2200000000

Default 1575420000

:FREQ:REFCLOck <value>

Set reference clock

Where <value> is an integer and one of:

0  Internal 1  External

Default 0 (internal)

:POWer:EthATTenuation <value>

Set attenuation to modify power output of the IQ signal. Note that this

and the :OUTput:STOp commands are the only command that can be sent while the GSS7725 is in the RUNNING state. Where <value> is an integer in dB Range 0 to 100 Where 0 is equivalent to -20 dB and 100 is equivalent to -120 dB

Default 0

:POWer:CALIBrate

Turn on calibration mode, this should be sent just prior to the :OUTput:STArt command.

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Command

Description

Default off

:FILe:FS <value>

Set sampling frequency of IQ file.

Where <value> is an integer in Hz and must be one of:

4000000  4 MS/s 16000000  16 MS/s 26000000  26 MS/s 51500000  51.5 MS/s 120000000  120 MS/s

Default 16000000

:FILe:FS:TARget <value>

Set the output (target) frequency of the RF. The IQ file will be converted to this frequency.

Where <value> is an integer in Hz and must be one of:

4000000  4 MS/s (for calibration only)

25000000  25 MS/s

:FILe:ENDianess <value>

Sets the endianness of the input file.

Where <value> is one of:

0  Big 1  Little

Default 0

:FILe:FILEpath “<path-str>”

Sets the IQ file path.

Where “<path-str>” is a string enclosed in quotes

No default

*RST

Reset all settings to defaults

:OUTput:STArt

Start the RF output

:OUTput:STOp

Stop the RF output

Note that when you disconnect from the GSS7725 controller the RF

output will stop automatically.

:STATus

Returns the current status of the GSS7725 Controller. The following

states can be returned:

CONNECTED  Remote connection waiting for command CONFIG  Setting internal status RUNNING  Generating RF ERROR  Blocking status due to error PROCESSING  The software is busy processing a remote

command

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Chapter 7: Calibration

The GSS7725 controller contains calibration files that match the GSS7725. This chapter describes the files and their location.

There are three csv files in

C:\Windows\System32\config\systemprofile\AppData\Roaming\.uhd\cal\

that hold IQ calibration data.

Figure 15 IQ calibration files

The file name includes the serial number of the GSS7725

There is another calibration file

CalibrationTable_UsrpEthAtt.csv that holds output level data that

can be found in

C:\Program Files\Spirent Communications\Positioning Applications\GSS7725\etc

The GSS7725 controller contains the software and drivers required to calibrate the GSS7725

7.1 Equipment required

GSS7725 Connected to GSS7725 controller PC with Ethernet GSS7725 controller GSS7725 controller Keyboard, mouse and monitor Connected to GSS7725 controller PC Power supply Power brick that comes with GSS7725 Ethernet cable Ethernet cable that comes with GSS7725 Power meter Agilent power meter type 'E4418B' or 'N1913A'

directly connected to the front RF output of the GSS7725

USB to GPIB adaptor Available from National Instruments connected from a

controller USB port to the power meter GPIB port

7.2 Testing the output level

In explorer navigate to the following directory:

C:\Program Files\Spirent Communications\Positioning Applications\GSS7725\etc

Run the following command as administrator:

Calibrate_test.bat

A script will now run to test the GSS7725 output level. At each frequency the power output of the GSS7725 will be read from the power meter. The power, if calibrated correctly should be -20dBm +/1dB. If all values are within -20dBm +/- 1dB the screen will show “PASS”. The script takes about 20 minutes to complete

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Figure 16 Calibrate_test.bat output

7.3 Calibrating the output level

In explorer navigate to the following directory:

C:\Program Files\Spirent Communications\Positioning Applications\GSS7725\etc

Run the following command as administrator:

calibrate.bat

The command should connect to the controller and run through a number of calibration routines at each frequency from 0.8GHz to 2.2GHz. This will take a while to run; eventually it will finish without error and produce a file within the

etc directory called:

CalibrationTable_UsrpEthAtt.csv

This file can be loaded in to Excel and the line plotted. It will look something like:

Figure 17 Calibration file plot

The command will also generate three csv files that hold IQ calibration data in

C:\Users\xxxx\AppData\Roaming\.uhd\cal were xxx is the account name (e.g. gpsadmin).

The

C:\Users\xxxx\AppData\Roaming\.uhd directory must be copied and pasted to

C:\Windows\System32\config\systemprofile\AppData\Roaming\ merging with the .uhd directory and

replacing any files at this location.

Restart the controller PC, this will automatically load the new calibration file

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Terms & Abbreviations

A.1 Simulator terms

Appendix Table A-1 Simulator terms

Term

Description

Stages of simulation

Definition

First stage

Specification of the scenario characteristics to produce a complete set of information that enables the system to operate

the Run Time

Run Time

Second stage

Uses the information from the first stage to calculate data that drives the signal generator to provide real-time stimuli to the

UUT.

Analysis

Third stage

Analysis and display of the logged data from the UUT, in

graphical or tabular form.

Cut-over

A scheduled change in the navigation data set transmitted by a satellite.

EUT

Equipment Under Test. See "UUT"

Host Computer

A computer that controls the Spirent signal generator. It prepares

data to drive the signal generator, analyses the results of the simulation and performs related housekeeping and miscellaneous

functions.

Interference Simulator

Spirent system that simulates adverse and hostile electromagnetic environments.

Model

Software program that applies algorithms to input data and

produces output data. Also used in the database to mean one complete set of input data

and output data from such a software program.

Multichannel Satellite Signal Source

GSS6560/5060/4750/7700 and STR4760/80/90 hardware units.

Scenario

A complete, named, description of a simulation.

Upload

A change in the navigation data set transmitted by a satellite

when the Control Segment updates the satellite's memory. Also used in the simulator to refer to data being used as a result

of the Control Segment Update.

UUT

Unit Under Test. The receiver being tested on the simulator.

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Terms & Abbreviations

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A.2 Abbreviations and acronyms

Appendix Table A-2 gives standard GPS, GLONASS and Galileo related abbreviations and acronyms.

Appendix Table A-2 Abbreviations and acronyms

Acronym

Description

GLONASS

GLObal Navigation Satellite System

Dip

Angle of dip of the earth’s magnetic field

PRS-NOISE

A signal with the same spectral distribution as PRS, but with an arbitrary

code structure of the correct chip rate that is phase and frequency

correlated with the other Galileo signals

PRN

Pseudo-Random Number, representing the unique transmitted signal code

A/J

Anti-Jamming

AOC

Auxiliary Output Chip

AODA

Age Of Data, Almanac

A-S

Anti-Spoofing

ASCII

American Standard Code for Information Interchange

BCD

Binary Coded Decimal

BITE

Built In Test Equipment

bps

Bits per second

BPSK

Bi-Phase Shift Keying

C/A code

Coarse/acquisition code

CDMA

Code Division Multiplex Access

CDU

Control Display Unit

C/No

Carrier to Noise Ratio

CRPA

Controlled Reception Pattern Antenna

CRC

Cyclic Redundancy Check

Commercial Service

CSV

Comma Separated Variable

Continuous Wave

DAC

Digital to Analogue Converter

DGPS

Differential GPS

DOP

Dilution Of Precision, caused by satellite geometry

dRMS

Distance Root Mean Square

Galileo carrier frequency

ECEF

Earth Centred Earth Fixed

ECI

Earth Centred Inertial

ECM

Electronic Counter Measures

EGNOS

European Geo-stationary Navigation Overlay System

EVTP

Enhanced Validation Test Program

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Terms & Abbreviations

Acronym

Description

FEC

Forward Error Correction

FOM

Figure of Merit

FRPA

Fixed Radiation Pattern Antenna

FRPAGP

FRPA Ground Plane

Gi(t)

Gold code (C/A ranging code)

GDOP

Geometric Dilution of Precision

GMT

Greenwich Mean Time

SPIRENT

Spirent Communications plc

GPS

Global Positioning System

GUI

Graphical User Interface

HDOP

Horizontal Dilution Of Precision

HOW

Hand -Over Word

Host Vehicle

ICD

Interface Control Document

Intermediate Frequency

ILS

Instrument Landing System

INS

Inertial Navigation System

IODC

Issue of Data, Clock

IODE

Issue of Data, Ephemeris

ISC

Inter-Signal Correction

JPO

Joint Program Office

J/S

Jamming to Signal Ratio

LAAS

Local Area Augmentation System

GPS primary D-band carrier frequency, 1575.42 MHz Galileo carrier frequency

GPS secondary D-band carrier frequency, 1227.6 MHz

GPS tertiary D-band carrier frequency, 1176.45 MHz

LRU

Line Replaceable Unit

Local Oscillator

LSB

Least Significant Bit

MCS

Master Control Station

MHz

Megahertz (106 Hz)

MSAS

MTSAT Satellite Augmentation System

MTSAT

Multi-functional Transport Satellite

MSB

Most Significant Bit

MSL

Mean Sea Level

Nav Data

Navigation data message

Nanosecond (10-9 second)

NSA

National Security Agency

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Terms & Abbreviations

GSS7725 Interference Generator User Manual

Acronym

Description

NSC

Non-standard C/A-code

NSY

Non-standard Y-code

Personal Computer

P code

Precise Code

PDOP

Position Dilution Of Precision

PLTS

Position Location Test System

PPS

Precise Positioning Service

PPSSM

PPS Security Module

PRN

Pseudo Random Noise

PRS

Public Regulated Service

PRSN

Public Regulated Service Noise

RCVR

Receiver

RINEX

Receiver Independent Exchange Format

Remote Terminal

S/A

Selective Availability

SAAS

Selective Availability and Anti-Spoofing

SBAS

Satellite Based Augmentation System (such as WAAS, EGNOS, and MSAS)

SPS

Standard Positioning Service

SSS

Satellite Signal Source

SVID

Satellite ID number

TDOP

Time Dilution Of Precision

TLM

Telemetry Word

TFOM

Time Figure Of Merit

TTFF

Time To First Fix

TOW

Time Of Week

User Equipment

UERE

User Equivalent Range Error

Universal Time

UTC

Universal Time Coordinated

VDOP

Vertical Dilution Of Precision

VDB

VHF Data Broadcast

WAAS

Wide Area Augmentation System

WGS84

World Geodetic System, 1984

Y code

Precise Code, A-S mode

1 PPS

1 Pulse Per Second

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Customer support

Spirent customer support

During normal office hours, you can contact Spirent Global Services in the United Kingdom, Asia Pacific and the USA by e-mail, fax or telephone. The Global Services contact details are on the next page.

Spirent Global Services can provide general information on any aspect of Spirent simulator hardware or software; or they can answer specific questions. Spirent Global Services is available to all customers under Warranty or with a maintenance agreement. Please note that Spirent Global Services is available to customers without a maintenance agreement, but Spirent is not obliged to provide solutions to any customer without a maintenance agreement.

Spirent Global Services aims to respond (or, where necessary, initiate a System Report) to any query within one working day (local and national holidays permitting).

Spirent requests you tell them when your simulator behaves in an unexpected, unusual or unacceptable way; including suspected faults or errors in the hardware, software or documentation.

Spirent’s fault reporting system will ensure Global Services can quickly return your simulator to normal working operation. After contacting Spirent Global Services to report a fault, Global Services staff will create a System Report (SR) and copy you with the SR reference number. Spirent Global Services request you use the SR reference number in all correspondence relating to that incident. All responses from Spirent in relation to your incident will contain the SR reference number.

When you first contact Spirent Global Services to report a fault, please provide the following information:

Your name

 Your e-mail address  Your telephone or fax number  The types and version numbers of your Spirent software  The serial number of your test unit (located on rear panel)  A comprehensive description of the incident

Where appropriate, provide:

 A copy of the [executable filename]_message_log.txt file  Copies of your scenario files, including all shared files. Provide a separate list, as a plain text

(*.txt) file, of all files you send Spirent.

 Details of the repeatability of the incident  Details of changes to the system, including any new software added and all upgrades

(including SimGEN, new hardware, new drivers, Spirent software and so on)

This will enable a swift response and improve the service to you.

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Spirent Global Services contact details:

In the US, Government/Contractors and Universities

Spirent Federal Systems Inc. 1402 W. State Rd. Pleasant Grove 84062 Utah USA

Tel: +1 801 785 1448 Fax: +1 801 785 1294 E-mail: help@spirentfederal.com

In the US Commercial, and rest of Americas

Spirent Communications Inc 2708 Orchard Parkway, Suite 20 San Jose California 95134 USA

Tel: +1.800.SPIRENT E-mail: support@spirent.com

Asia Pacific (All Positioning Customers)

Spirent Communications,

Shining Tower, No. 35, Xueyuan Road, Room 1302, Beijing 100083, China

Contact Global Support Tel (Toll free mainland China): 4008109529 Tel (Outside mainland China): +86 4008109529 Fax: +86 1082330022 E-mail: help_asia@spirent.com

All other Regions and Positioning Customers

Spirent Communications plc,

Aspen Way, Paignton, Devon TQ4 7QR United Kingdom

Contact Global Support: Tel: + 44 1803 546333 Fax: + 44 1803 546302 E-mail: help@spirent.com

Go to http://support.spirent.com

for access to Spirent’s Global Support, FAQ and document

databases.

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Index, figures and tables

Index and list of Figures and Tables

Index

1 PPS, A-4

A/J, A-2 Almanac, A-2 Analysis, A-1 AOC, A-2 AODA, A-2 A-S, A-2, A-4 ASCII, A-2

Bandwidth, 2-1 BCD, A-2 BITE, A-2 bps, A-2 Bps, A-2 BPSK, A-2 Broadcast, A-4

C/A code, A-2, A-3, A-4 C/No, A-2 CDMA, A-2 CDU, A-2 Commercial Service, A-2 CRC, A-2 CRPA, A-2 CS, A-2 CSV, A-2 Cutover, A-1 CW, A-2

DAC, A-2 Definition, A-1 DGPS, A-2 Dip, A-2 DOP, A-2 dRMS, A-2

E5, A-2 E6, A-2 ECEF, A-2 ECI, A-2 ECM, A-2 EGNOS, A-2, A-4 Ephemeris, A-3 EUT \b, A-1 EVTP, A-2

FEC, A-3 FOM, A-3 Frequency Range, 2-1 Frequency Resolution, 2-1 Frequency Stability, 2-1 FRPA, A-3 FRPAGP, A-3

Galileo, A-2, A-3 GDOP, A-3

Gi(t), A-3 GLONASS, A-2 GMT, A-3 GNSS signal level, 2-1 GNSS signal level accuracy, 2-1 GNSS signal level control, 2-1 GPS, 3-1, 5-6, 5-9, A-2, A-3 GUI, A-3

Harmonics, 2-1 HDOP, A-3 Host Computer, A-1 HOW, A-3 HV, A-3

I/S ratio relative to nominal GPS C/A signal level, 2-1 ICD, A-3 ICU, 3-1 IF, A-3 ILS, A-3 In band flatness, 2-1 In band spurious, 2-1 INS, A-3 Interactive mode, 5-1, 5-4 Interference accuracy, 2-1 Interference level expressed as absolute power

1, 2-1

Interference level resolution, 2-1 Interference Simulator, A-1 IODC, A-3 IODE, A-3 ISC, A-3 ISG - obsolete, 2-1

J/S, 5-6, 5-9, A-3 JPO, A-3

L1, 3-1, A-3 L2, 3-1, A-3 L5, A-3 LAAS, A-3 LO, A-3 LRU, A-3 LSB, A-3

MCS, A-3 MHz, 4-1, A-3 Model, A-1 Motion, 3-1 MSAS, A-3, A-4 MSB, A-3 MSL, A-3 MTSAT, A-3 Multichannel Satellite Signal Source, A-1

Nav Data, A-3 Navigation Data (Nav. Data), A-3 ns, A-3 NSA, A-3 NSC, A-4

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NSY, A-4

On, 5-7

P code, A-4 P Code, A-4 PC, A-4 PDOP, A-4 PLTS, A-4 PPS, A-4 PPSSM, A-4 PRN, A-2, A-4 PRS, A-2, A-4 PRS Noise, A-4

RCVR, A-4 RINEX, A-4 RT, A-4 Run Time, A-1

S/A, A-4 SAAS, A-4 SBAS, A-4 Scenario, 3-1, 5-2, 5-3, 5-4, A-1 Signal Level, 5-8, 5-9 SPS, A-4

SSG, 3-1 SSS, A-4 SVID, A-4

TDOP, A-4 TFOM, A-4 TLM, A-4 TOW, A-4 TTFF, A-4

UE, A-4 UERE, A-4 Upload, A-1 UT, A-4 UTC, A-4 UUT, A-1

VDB, A-4 VDOP, A-4

WAAS, A-4 WGS84, A-4

Y code, A-4 Y Code, A-4

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Index, figures and tables

List of Figures

Figure 1 GSS6300Mi & GSS7725 Hardware Connectivity .............................................................. 4-1

Figure 2 GSS6700 & GSS7725 Hardware Connectivity ................................................................. 4-2

Figure 3 GSS7000 & GSS7725 Hardware Connectivity ................................................................. 4-2

Figure 4 GSS9000 & GSS7725 Hardware Connectivity ................................................................. 4-3

Figure 5 Antenna Signal Types dialog ............................................................................................. 5-1

Figure 6 Scenario tree ..................................................................................................................... 5-2

Figure 7 Select File dialog ............................................................................................................... 5-3

Figure 8 Interference Simulation File editor..................................................................................... 5-3

Figure 9 Interference Window ......................................................................................................... 5-4

Figure 10 Command type - Comment ............................................................................................. 5-5

Figure 11 Command type - Interference Custom Waveform 7725.................................................. 5-6

Figure 12 Command type – Interferer RF on/off ............................................................................. 5-7

Figure 13 Command type – Interferer Level .................................................................................... 5-8

Figure 14 Command type – Interfere Delta level ............................................................................. 5-9

Figure 15 IQ calibration files ............................................................................................................ 7-1

Figure 16 Calibrate_test.bat output ................................................................................................. 7-2

Figure 17 Calibration file plot ........................................................................................................... 7-2

DGP01448AAA 6-00

C-4 Index, figures and tables

List of Tables

Table 1-1 Formats used in this document ....................................................................................... 1-4

Table 2-1 GSS7725 Technical Performance ................................................................................... 2-1

Table 2-2 GSS7725 Connectivity .................................................................................................... 2-1

Table 2-3 GSS7725 Environmental & Safety parameters ............................................................... 2-2

Table 2-4 GSS7725 Operating parameters ..................................................................................... 2-2

Table 2-5 GSS7725 Default Waveform Definitions ......................................................................... 2-3

Table 5-1 Mode of operation with a user action file and an interference file ................................... 5-9

Table 5-2 GSS7725 SimGEN remote commands ........................................................................... 5-10

Table 6-1 GSS7725 configuration file parameters .......................................................................... 6-1

Table 6-2 GSS7725 full command syntax ....................................................................................... 6-2

Table 6-3 GSS7725 standard command return value ..................................................................... 6-2

Table 6-4 GSS7725 remote commands .......................................................................................... 6-2

Appendix Table A-1 Simulator terms ............................................................................................... A-1

Appendix Table A-2 Abbreviations and acronyms .......................................................................... A-2

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GSS7725 Interference Generator User Manual Software for the Spirent Range of Satellite Navigation Simulation Products

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Document number: DGP01448AAA

Document Issue: 6-00

Date: August 2017

Printed in England

Spirent GSS7725 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual