Comtech Mobile Datacom CMDCMTM203 L Band Satellite Earth Station User Manual

Comtech Mobile Datacom L Band Satellite Earth Station

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User Manual

Comtech Messaging System (CMS)

MTM-203 Transceiver Module

End User Manual

Document Version: B

Document Number: CMDC-DOC-0138

Author: Kerry Keksz

Date: November 1, 2006

Privilege Level: Customer

Transceiver Host Firmware: 3.4T

Transceiver DSP Firmware: Altera 0.227

This document is property of Comtech Mobile Datacom, Germantown, Maryland.

This document is not to be disclosed to persons outside the organization without written authorization and execution of

Comtech Mobile Datacom Corporation (hereafter referred to as ‘Comtech’) is a subsidiary of Comtech

Telecommunications Corporation.

This document contains confidential business or system information. Any possession, use, or copying of this material

requires prior written permission from Comtech.

Comtech shall not be liable for technical or editorial errors or omissions contained herein. The information in this

document is provided “as is” without warranty of any kind and is subject to change without notice. The warranties for

Comtech products are set forth in the express limited warranty statements accompanying such products. Nothing

herein should be construed as constituting an additional warranty.

Product names mentioned herein may be trademarks of their respective companies.

Product is Patent Pending.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

REVISION HISTORY

Revision Date Revision By Whom Description of the Changes

11/1/06 B Lajuana

Johnson Modified page 34 the Regulatory

Compliance section of the document to

include regulatory information as

required by the FCC.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Notices

Throughout this manual, a user will see: WARNINGS, CAUTIONS, NOTES, and

TIPS.

WARNINGS are for procedures that, if not followed, may result in personal

injury or death.

CAUTIONS are for procedures that, if not followed, may result in hardware

or software damage or failure.

NOTES are included to provide the operator with additional information

intended to simplify a step or entire procedure.

TIPS are included for the operator detailing useful information about using

the equipment and software.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Safety steps to follow if someone is the victim of electrical shock

1. Do not try to pull or grab the individual.

2. If possible, turn off the electrical power.

3. If you cannot turn off the electrical power, pull, push or lift the person

to safety using a dry wooden pole, or dry rope or some other insulated

material, send for help as soon as possible.

4. After the injured person is free of contact with the source of electrical

shock, move the person a short distance away and immediately render

first aid, as applicable.

WARNING: If nuclear, biological, or chemical (NBC) exposure is

suspected, all air filter media will be handled by personnel wearing full NBC

protective equipment.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Table of Contents

1. About this Manual ..............................................................................................7

1.1. Purpose of this Section..................................................................................................7

1.2. Intent of this Document.................................................................................................7

1.3. Terminology Clarification.............................................................................................7

1.4. Conventions Used in this Document.............................................................................7

1.5. Description of Document Contents...............................................................................7

2. Introduction to the Comtech Network..............................................................9

2.1. Purpose of this Section..................................................................................................9

2.2. Components of the Network .........................................................................................9

2.3. Agent...........................................................................................................................10

2.4. Transceiver..................................................................................................................11

2.4.1. Transceiver Subsystems.........................................................................12

2.4.2. High Power Amplifier (HPA) Subsystem...............................................12

2.4.3. Modulator Subsystem ............................................................................12

2.4.4. Synthesizer Subsystem ...........................................................................12

2.4.5. Baseband Subsystem..............................................................................12

2.4.6. Low Noise Amplifier (LNA) and R/F I/O Mux Subsystem .....................12

2.4.7. Down Conversion and A/D Subsystem ..................................................13

2.5. Transceiver Operational Considerations.....................................................................13

2.6. Client API and Command Set (Agent and Transceiver).............................................13

3. Integrating the MTM-203 into a Device .........................................................15

3.1. Purpose of this Section................................................................................................15

3.2. Needed Materials for Integration ................................................................................15

3.2.1. MTM-203 Interface Requirement ..........................................................15

3.2.2. External Power Supply Requirements ...................................................16

3.2.3. External GPS Requirements..................................................................16

3.3. Physical Interface Description ....................................................................................16

3.4. Mounting the Transceiver in a Device........................................................................17

3.5. Connecting to the Transceiver ....................................................................................17

3.5.1. Control Interface ...................................................................................17

3.5.2. LEDs......................................................................................................19

3.5.3. P2 Connector.........................................................................................19

3.5.4. Antenna Interface ..................................................................................19

3.5.5. External GPS Connector .......................................................................21

3.6. Booting-up the Transceiver.........................................................................................21

3.7. Provisioning................................................................................................................23

4. Indicators and Diagnostics...............................................................................24

4.1. Purpose of this Section................................................................................................24

4.2. Using LEDs.................................................................................................................24

4.2.1. LED A....................................................................................................24

4.2.2. LED B....................................................................................................24

4.2.3. LED C....................................................................................................24

4.2.4. Interpreting LEDs during Boot-Up .......................................................24

4.3. Displaying Receiver Lock Status................................................................................24

4.4. Measuring Signal to Background Noise......................................................................25

4.5. Interpreting Signal to Noise Measurement..................................................................25

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

5. Troubleshooting ................................................................................................26

5.1. Purpose of this Section................................................................................................26

5.2. Error Messages............................................................................................................26

5.3. Troubleshooting the MTM-203...................................................................................26

6. Customer Support Contact Information........................................................30

7. Warranty ...........................................................................................................31

Appendix A – Specifications....................................................................................32

Power Specifications.............................................................................................................32

Environmental / Mechanical Specifications..........................................................................32

Input/Output (I/O) Specifications .........................................................................................32

Satellite Channel Specifications............................................................................................33

Regulatory Compliance.........................................................................................................34

Appendix B – Mechanical Drawings....................................................................... 35

Physical Description .............................................................................................................35

Glossary......................................................................................................................37

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

1. About this Manual

1.1. Purpose of this Section

The purpose of this section is to introduce the user to the terminology and layout of this

manual.

1.2. Intent of this Document

This document is intended for users who are seeking a general overview of Comtech’s

transceivers. This document provides a general introduction and understanding of:

• transceiver functions

• transceiver integration and connectivity

• transceiver diagnostics

• common errors and troubleshooting

Comtech’s transceivers support multiple privilege levels. This document is intended for

users with “Customer” level access to a transceiver.

1.3. Terminology Clarification

Throughout this document the term “transceiver” refers to the MTM-203 transceiver

(satellite antenna). The term “Agent” refers to the program that allows users to connect

to the terrestrial component of the Comtech network.

1.4. Conventions Used in this Document

To distinguish between API commands entered by a user or application and various API

outputs. This document uses two different font formats.

Commands All interface commands are in 10 Point Black Bold Courier Font.

Commands are case sensitive. All commands must be entered in lower

case.

Responses All interface responses and outputs are in 10 Point Blue Verdana Font.

1.5. Description of Document Contents

This document is organized into functional sections described in Table 1. Some sections

of the document are targeted for users who know very little about the Comtech network,

other sections are for more experienced users who are interested in configuring the

MTM-203 transceiver.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Table 1: Document Structure

Section # Description Target Audience

Chapter 2:

Introduction to the

Comtech Network

This section provides a brief overview of the

Comtech network, and introduces the reader to the

major components of the network.

Users who are unfamiliar with the

Comtech Network.

Chapter 3: Integrating

the MTM203 into a

Device

Appendix A:

Specifications and

Appendix B:

Mechanical

Description

These sections provide an understanding of the

transceiver interface and how to physically

integrate the transceiver into a device. Appendix A

and B include specifications and mechanical

drawings that detail the transceiver’s physical

description.

Users and organizations who intend

to build their own cable sets (rather

than using cables provided by

Comtech) and/or users who are

integrating the transceiver into a

device for the first time.

Chapter 4: Indicators

and Diagnostics This section describes the LEDs (Light Emitted

Devices) and their functions. Users who want to verify transceiver

operations when integrating the

transceiver into a device. This section

is also used for diagnostics.

Chapter 5:

Troubleshooting This section describes error messages, including

“Bad command” message, and describes

troubleshooting techniques.

Users who want to understand error

messages and troubleshoot problems.

Chapter 6: Customer

Solutions This section provides contact information for

Customer Solutions. Users who are unable to resolve

problems after referring to

Diagnostics and Troubleshooting

sections.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

2. Introduction to the Comtech Network

2.1. Purpose of this Section

This section provides a brief overview of the Comtech network, and introduces the major

components of the network. The focus of this section is to introduce the Agent and the

Transceiver.

2.2. Components of the Network

The following figure illustrates the Comtech Network Architecture and is followed by a

description of the network components.

Figure 1: Comtech Network Architecture.

Application Development Area

Customer

n Customer X

Communications Satellite

GPS

Satellite

Transceiver

Client

Transceiver

Customer

422

Serial

gent

Client

gent

Client

gent

Client

gent

Client

TCP/IP

Transceiver

Customer

TCP/IPP

Transceiver

Client

422

Serial TCP/IP TCP/IP

Comtech Hub

Network Packet Switch

Agent X

Session

X-1 Session

X- n

Agent n

Session

n-1 Session

n-n

The Comtech Mobile Datacom Network consists of three main components:

• Network Packet Switch

• Hub

• Transceiver

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

The Network Packet Switch (or Switch) is a set of ground station computers through

which all network traffic is routed. The Switch can support many different types of

connections:

• VSAT

• Internet

• Leased line

• Dialup

The Switch’s primary function is to handle the routing of network traffic. The Switch has

several processes to support this function. Of the processes running on the Switch, the

Agent process is the most important process to a customer. An Agent is one of the access

points a customer can use to send messages via the CMS. Section 2.3 describes the

functions and workings of an Agent in more detail. For security purposes, the Switches,

and therefore the Agents, are protected via a firewall.

The Comtech Hub is connected to the Switch. The Hub contains radio frequency (RF)

modulation and demodulation equipment. The Hub’s primary function is to transform

data into a radio frequency signal and a radio frequency signal into data. The Hub takes

outgoing TCP/IP packets from the Switch and transforms them into signals that are then

transmitted up to the satellite and down to a transceiver. The Hub also takes the incoming

signals sent from a transceiver via satellite and transforms them into TCP/IP packets that

can be processed by the Switch.

The transceiver is a customer’s other access point into the Comtech Network. A

transceiver’s primary function is to act as an antenna. A transceiver sends and receives

messages as directed by the client application that is connected to it. A transceiver also

has some on-board processing capabilities that allow it to send messages autonomously.

Section 2.4 describes the functions and workings of a transceiver in more detail.

2.3. Agent

An Agent is a process that runs on the Network Packet Switch. An Agent’s main function

is to manage message traffic for a given customer. Typically, each customer is assigned a

separate agent, thereby creating a VPN (Virtual Private Network) for each customer.

Customers cannot access each other’s Agents, unless the customer instructs Comtech to

permit such access.

The Agent performs the following functions to incoming messages:

• Accepts messages from transceiver or client connections

• Decrypts messages

• Delivers messages to their intended recipients

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

The Agent performs the following functions to outgoing messages:

• Accepts messages from a client connections

• Encrypts the outgoing messages

• Sends messages through the Comtech network

Customers with specific processing requirements often have applications that connect to

the Agent. Each Agent has a process focused on listening on a specific TCP/IP port for

incoming client connections. Once an Agent receives an incoming connection, the Agent

forks (spawns) a child dedicated to servicing the client. This child process will continue

to service the client until the client application closes the TCP/IP connection. An Agent

can service up to 64 separate connections.

2.4. Transceiver

The MTM-203 Transceiver is a compact module that can easily be integrated into a

device. The transceiver’s primary function is to allow users and applications the ability to

send and receive messages via satellite. Using the GPS receiver, a transceiver can

“piggyback” location information on each message. A transceiver can also transmit its

location automatically.

The MTM-203 Transceiver module provides the following features:

• Small, two-sided board to easily integrate into a device

• Includes a single serial interface, at TTL levels

• Supports API commands using the serial interface

• Contains internal GPS device with capability to connect to an external GPS

device. The internal GPS pass-through model provides an RF signal to the

external GPS for both L1 and L2 frequencies

• Low power operation to minimize battery consumption and can connect to an

external power supply

• Ensures GPS receiver can receive RHCP signal, regardless of communication

channel polarization

• Allows for dual polarization antenna use

• Provides overload protection on the receive channel to prevent LNA burn-out

for large signals

• Allows for FPGA code loading via an external serial port at rates higher than

normal API rates

• Ensures a short power on to operational period, including less than 1 sec

FPGA load times

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

2.4.1. Transceiver Subsystems

The following figure illustrates the MTM-203 Transceiver subsystems. A description of

each subsystem follows.

Figure 2: MTM-203 Block Diagram of Subsystems.

2.4.2. High Power Amplifier (HPA) Subsystem

The HPA subsystem is comprised of amplifiers and converter circuitry to boost signal

sufficiently for transmissions.

2.4.3. Modulator Subsystem

The Modulator subsystem processes the signal from the baseband subsystem for

amplification by the HPA.

2.4.4. Synthesizer Subsystem

The Synthesizer subsystem provides the timing signals to synchronize the other

subsystems.

2.4.5. Baseband Subsystem

The Baseband subsystem is comprised of a Field Programmable Gate Array (FPGA) and

Central Processing Unit (CPU), which process the received and transmitted signals.

2.4.6. Low Noise Amplifier (LNA) and R/F I/O Mux Subsystem

The LNA, R/F, and I/O Mux subsystem processes the receive signal for use by the down

converter.

(Amplifiers and Related

Circuitry)

Modulato

D/A and

Up-converter

LNA and RF I/O MUX

Including R/L and T/R

Switches

Down Converter & A/D

Synthesize

DDS and Related Circuitry

(shared between the

transceiver and receiver)

Baseband

(FPGA and CPU)

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

2.4.7. Down Conversion and A/D Subsystem

The down converter and A/D subsystem processes the received signal for use by the

baseband.

2.5. Transceiver Operational Considerations

The transceiver enables satellite communications via an external antenna. Therefore, the

external antenna must be able to “see” the satellite in order to function properly. The

transceiver is designed to operate outdoors with an unobstructed view of the southern

sky. Some obstacles that can block the transceiver include tall buildings, tunnels, parking

garages, and dense forests. The transceiver may operate inside of a building provided the

antenna is positioned in a window with a view of the satellite, and provided the window

is not coated with a reflective material.

In addition to large visible obstacles, multi-path interference may hinder a transceiver

from receiving optimally. Multi-path interference occurs when multiple signals arrive at

an antenna having traversed different paths. Multi-path is due to reflections from objects

(surfaces) located near the transceiver. In most cases, moving the transceiver a few feet

(sometimes inches) in one direction or another will alleviate the interference caused by

multiple signals.

NOTE: Since the communications receiver and the GPS receiver are two separate

receivers, each performs (receives its signal) independently. A partition of the front-

end receiver is common between the GPS path and the message receiver path.

Therefore, it is possible for the antenna to receive messages but not have a valid

GPS fix. The reverse is also true.

NOTE: Comtech’s transceivers are designed to operate in the United States of

America in accordance with Federal Communications Commission (FCC)

regulations (authorization pending as of 05/16/06). To operate in the U.S., the MTM-

203 transceiver must adhere to FCC regulations regarding mobile radio

transmitters which use L-Band. By regulation, a transceiver operating in the U.S.

must be configured so that it will not transmit if its receiver is not in lock (locked

onto the satellite signal). Therefore, any Comtech transceiver operating in the U.S. is

configured not to transmit if the transceiver’s receiver is out-of-lock. Transceivers

may be configured differently in other countries.

CAUTION: External antennas should not be positioned within six feet of each

other. Antennas that are too close together may result in equipment damage.

CAUTION: Do not place equipment directly on wet ground, snow, or ice for

operations.

2.6. Client API and Command Set (Agent and Transceiver)

As previously stated, the CMS provides two basic access points, the Agent and the

transceiver. Each access point has its own Application Programming Interfaces (APIs).

These APIs allow external applications to use the platform as a conduit for application

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

message exchange and for other supported functions (such as mobile GPS tracking). The

APIs may be engaged directly by users or by application programs.

In the spirit of the traditional client-server model, this document will use the general

terms ‘client’ and ‘server’ when referring to components of a Comtech messaging

implementation. In this context, a client will generally refer to any external entity that

engages an Agent or Transceiver API. This may include any of the following variations:

• A user accessing the API directly (typically via a terminal communications

utility such as TELNET).

• A user interface application that bridges between the API and a user.

• An automated application.

The term ‘server’ will generally refer to a specific instance of an Agent or Transceiver

API.

The Agent and Transceiver components each provide an API for external clients. Both

APIs consist of an interactive command line interpreter (CLI) that is generally activated

when a client establishes a connection.

The CLI presents a command prompt and allows the client to issue specific commands to

the server process of the respective Agent or Transceiver. The server will generally

respond to client commands with action (such as changing a session setting), data output

(such as displaying current settings), or both. Certain commands may prompt the client

for additional input.

The CLI operates synchronously. It issues a new command prompt only after it

completes execution of the previous command. The client must wait for a prompt before

submitting subsequent commands (i.e., the CLI does not support type-ahead).

In certain situations, the CLI may present unsolicited information to the client while the

client is issuing commands (primarily in the case of message arrival). However, this

behavior can be suppressed and/or controlled in most cases.

Interaction between client and API will usually be discussed in the context of a ‘session’.

In the case of an Agent, a session is generally defined as the period of the TCP/IP

connection between client and Agent. In the case of a Transceiver, a session is best

described as the operational period of the transceiver following boot-up.

The session concept implies a period in which the configuration of the Agent or

Transceiver (with respect to commands issued by the client) is retained. In the case of an

Agent, all session contexts are lost when the TCP/IP connection is broken. In the case of

the Transceiver, session context is generally retained as long as the transceiver is

continuously operating – whether or not the client is actively engaging the serial

interface. (Note: The CMDC concept of session may not necessarily apply to that of a

particular client application.)

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

3. Integrating the MTM-203 into a Device

3.1. Purpose of this Section

The purpose of this section is to provide guidance for integrating the Comtech Mobile

Datacom MTM-203 Transceiver Module into a device. The focus of this section is to

describe transceiver integration, including material requirements and a detailed

description of the MTM-203 transceiver interface and connectors.

3.2. Needed Materials for Integration

The following materials are needed to integrate the MTM-203 Transceiver Module into a

device:

• Antenna, cable, and connectors

• Power supply

• Optional Military GPS Receiver

3.2.1. MTM-203 Interface Requirement

Required Performance Characteristics for Antenna

Gain +1dBiC minimum for elevation angles between 20 degrees and 60

degrees

Impedance 50 ohms

Polarization for

use in the USA Right-hand circularly polarized (RHCP). The transceiver can be

operated with a single RHCP antenna connected to the RHCP port

or a dual pole antenna with both RHCP and LHCP ports connected.

Polarization for

use outside the

USA

RHCP is required as a minimum. LHCP can be added for

additional satellite coverage options.

Connector Type Cable connectors must be compatible with the type SSMB coaxial

connectors on the MTM-203 module antenna ports. Manufacturer

and part number used for these parts are AEP p/n 7209-1511-050

(alternate supplier is COAXICOM p/n 6M230SL-1).

Max Loss Total combined loss for cable and connections should be no more

than .5dB at 1.6 GHz

Tx Modulation BPSK DS-SS

Tx Frequency 1626.5 – 1660.5 MHz

Tx Level 36.9 dBm Max

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Rx Modulation BPSK DS-SS

Rx Frequency 1525 – 1559 MHz – Communication Channel

1575.42 +/- 13 MHz - GPS L1

1227.60 +/- 13 MHz - GPS L2

Rx Level -131 dBm

GPS Rx

Modulation BPSK DS-SS

GPS Rx Frequency 1525 – 1559 MHz – Communication Channel

1575.42 +/- 13 MHz - GPS L1

1227.60 +/- 13 MHz - GPS L2

GPS Rx Level -107 dBm

Approvals Must pass Comtech System/Network Compliance Approval Process

to be fielded outside of test/development environment.

The wire gauge should be 20 AWG for the cable connection to the MTM-203’s

24 position control interface connector (P1) (Molex, Part Number 87831-2420).

3.2.2. External Power Supply Requirements

The VBAT input to the MTM-203 Transceiver module must be between 6.5V to 15

VDC.

3.2.3. External GPS Requirements

An external GPS RF 50 ohm, -107 dBM (see Table 4) device may be connected to the

MTM-203 transceiver. The cable from the External GPS Input port should have an

SSMB connector.

3.3. Physical Interface Description

There are two hardware interface points on the MTM-203 Transceiver Module (Figure

3): the Control Interface and the Antenna Interface.

The Control Interface manages the communication between the data source and the

transceiver. This interface is also used for loading configuration data and updating the

firmware of the module. Power for the MTM-203 Transceiver Module must be provided

through this interface.

The antenna interface consists of three coaxial connectors, two of which deliver the

received signal from either a left hand (LH) or right hand (RH) circularly polarized

(RHCP) antenna to the corresponding low noise amplifier (LNA) circuitry, and the

transmit signal from the High Power Amplifier (HPA) to the antenna. Since the module

operates only in half-duplex mode, only transmit or receive signal will be present at this

interface at any given time. The RF signal from the RHCP antenna is also fed to the on-

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

board GPS device. The transceiver may be configured to automatically switch from LH

to RH (or vice versa) by using the API command to implement worldwide autonomy.

The third coaxial connector is an external GPS input for feeding the RF signal to an

external GPS unit.

Figure 3: MTM-203 PC Board showing connectors and LEDs.

3.4. Mounting the Transceiver in a Device

Appendix B provides a mechanical drawing of the MTM-203 module describing

mounting holes that should be used to secure the module in a device.

3.5. Connecting to the Transceiver

3.5.1. Control Interface

The Control Interface is implemented in the P1 connector (Molex, Part Number 87831-

2420) located on the topside of the MTM-203 module. The following table describes the

P1 connector pin-outs and the function of each pin on this connector.

Table 2: P1 Control Interface Pin-outs

Pin-outs Input/Output (I/O) Pin Description

LED-D P2 Connector

External GPS

Connector (J1)

ntenna-RHCP (J2)

Connector

ntenna-LHCP

(J3) Connector

LED-C

LED-B

P1 Connector LED-A

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Pin-outs Input/Output (I/O) Pin Description

1 N/A GND

2 Input VBATT (6.5 – 15 V)

3 N/A GND

4 Input VBATT (6.5 – 15 V)

5 Output LED-C – Flashes during configuration and

remains on once the console is configured

and ready. D3 LED on the PC board.

6 Output LED-A – Illuminates while transmitting

and illuminates during boot. D1 LED on

the PC board.

7 Output LED-B – Illuminates indicating that the

receiver is in lock and High-Level Data

Link Control (HDLC) is in-sync when lit.

D2 LED on the PC board.

8 Output AUX_PWR CNTL

9 Input IGN_SENSE

10 Input MAIN CNTL (ON/OFF) – Turns module

off at .5V. Turns module on at >1.5V. Do

not exceed 30V.

11 I/O User Defined: 0–3 V, 8 mA, max, 3 V

logic

12 I/O User Defined: 0–3 V, 8 mA, max, 3 V

logic

13 I/O User Defined: 0–3 V, 8 mA, max, 3 V

logic

14 I/O User Defined: 0–3 V, 8 mA, max, 3 V

logic

15 Input AUX UART RX IN – Future development

16 Output AUX UART TX OUT– Future

development

17 Input SER DAT IN – Supports communications

using Comtech API commands.

18 Output SER DAT OUT – Supports

communications using Comtech API

commands.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Pin-outs Input/Output (I/O) Pin Description

19 Output 3.3 V – Provides debugging. Not

recommended for any other use.

20 Output LED-D – FPGA LED

21 Input GPS Keep Alive – 1.95-3.6V (40 μA max.

3.3 V) external power supply to keep the

GPS device's real-time clock and backup

RAM. Connecting it to the

3.3 V on pin 19 will speed up the fix

acquisition of the GPS when using API

commands to control power to the internal

GPS module. Connect to ground if not

used.

22 NC

23 NC

24 NCU

3.5.2. LEDs

Figure 3 illustrates four LEDs: A–D, next to the P1 connector on the top-side of the

MTM-203 Transceiver Module. The function of LEDs A-C is also specified in Table 2.

LED-D indicates hardware receive lock from the FPGA. “On” indicates that the FPGA is

locked to the received signal. The LED will flicker if the signal is weak and the receiver

is reacquiring.

3.5.3. P2 Connector

Figure 3 shows a P2 connector between the LEDs and the antenna interface connectors.

The P2 connector was only available during development and is now disabled.

3.5.4. Antenna Interface

The antenna interface on the MTM-203 Transceiver consists of three coaxial connectors:

two connectors for an external antenna and a third connector for an external GPS module.

Antenna-LHCP (J3)

Connector J3 feeds the LHCP LNA circuitry when in receive mode and connects to the

LHCP HPA circuitry when the transceiver is in transmit mode.

Antenna-RHCP (J2)

Connector J2 feeds the RHCP LNA circuitry in the receive mode and connects to the

RHCP HPA circuitry when the transceiver is in transmit mode. The RHCP LNA also

feeds the internal GPS module as well as the J1 connector.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

The following table describes the electrical characteristics of the signal in transmit (TX)

and receive (RX) directions.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Table 3: Antenna LHCP and RHCP TX and RX Signal Characteristics

Signal

Characteristic Transmit (TX) Receive (RX)

Modulation BPSK DS-SS BPSK DS-SS

Frequency 1626.5 – 1660.5

MHz 1525 – 1559 MHz – Communication Channel

1575.42 +/- 13 MHz - GPS L1

1227.60 +/- 13 MHz - GPS L2

Level 36.9 dBm Max -131 dBm

3.5.5. External GPS Connector

The third coaxial connector, J1, feeds the GPS signal to an external GPS module. The

signal output from this connector is only available when the unit is in the receive

mode. The following table describes the electrical characteristics of the signal for this

connector.

Table 4: External GPS Rx Signal Characteristics

Signal

Characteristics Receive

Modulation BPSK DS-SS

Frequency 1525 – 1559 MHz – Communication Channel

1575.42 +/- 13 MHz - GPS L1

1227.60 +/- 13 MHz - GPS L2

Level -107 dBm

3.6. Booting-up the Transceiver

When applying power to the MTM-203 module, or on system reboot, the transceiver

module will go through a standard boot sequence. Boot-up will last a minimum of five

seconds, but may take longer depending on the boot time-out setting.

The command to reboot the transceiver module is reboot. The following table describes

the various trace statements that display upon boot up.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Table 5: Boot Trace Description

Line

# Boot Trace Statement Explanation

1 Default boot Displays type of boot: default, cold, or warm.

2 CMDC GEN2 Terminal Displays type of CMDC transceiver

3 Power On Self Test:

Passed Indicates a self test was performed, which

includes a test of the FPGA, RX PLL, TX PLL,

GPS, Temperature, and Battery. If a Self Test

failed, the response would show which systems

passed and which systems failed.

Example Failed Self Test:

> reboot

Reboot in progress....

Default boot - Watchdog reset

CMDC GEN2 Terminal

Power On Self Test: 0x20

FPGA: Passed

RX PLL: Passed

TX PLL: Passed

GPS: Passed

TEMPERATURE: Passed

BATTERY: Failed Code: 0x2

ID ok.

4 ID ok. Indicates that the transceiver module has been

provisioned with a permanent identity. If this

line does not state “ID ok,” the transceiver has

not been provisioned correctly.

5 >

Displays command prompts indicating system is

booting up.

6 >api reset Sets the transceiver to interactive mode with the

echo on (display commands). This mode saves a

user from typing the entire commands. As the

user types in the first few characters of a

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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Line

# Boot Trace Statement Explanation

command, the transceiver will attempt to

interpret the characters and then prompt the user

with a known command.

7 > show version? Indicates that what follows are system software

versions.

8 Boot 2.2.E Indicates version of the boot loader the

transceiver is running.

9 Host 3.4.T Indicates version of the Host application that is

running.

10 ALTERA 0.227 Indicates version of the FPGA application that is

running.

11 RTOS 2.70 Indicates version of the receiver operating

system that is running.

12 > Displays the command prompt.

3.7. Provisioning

CMDC ships all transceivers fully provisioned. Provisioning establishes the profile of

configuration commands inherent to the transceiver as to its operation within the Agent.

These configuration settings also adhere to specific requests from the customer as to the

behavior of the transceivers interfacing with their software.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

4. Indicators and Diagnostics

4.1. Purpose of this Section

The purpose of this section is to provide basic diagnostics to integrate the MTM-203 into

a device. The focus of this section describes how to use the LEDs to interpret transceiver

activity and verify system operations.

4.2. Using LEDs

There are three Light Emitting Diodes (LEDs) on the top side of the transceiver between

the P1 and P2 connectors (see Figure 3). Each LED represents a transceiver state.

4.2.1. LED A

LED A represents the status of the transmitter. When LED A is on (flickers), the

transceiver is transmitting. When LED A is off (not illuminated), the transceiver is not

transmitting. Upon each transmission, LED A will turn on for a few milliseconds.

4.2.2. LED B

LED B represents the status of the receiver. When LED B is on solidly (not flickering),

the receiver is in-lock. When LED B is on, but the light is flickering, the receiver is out-

of-lock. Since the transceiver is half-duplex, upon each transmission, the LED will turn

off for a few milliseconds, indicating the receiver is momentarily out-of-lock.

4.2.3. LED C

LED C represents the status of the console or the interface. When LED C is on, the

transceiver’s interface is available. If LED C is off continuously, the transceiver’s

interface is unavailable and generally indicates a buffer overflow.

4.2.4. Interpreting LEDs during Boot-Up

If the LEDs are operating in the led normal state, during boot up, the LEDs will cycle a

number of times in what appears to be a random order. Although the process appears

random, the LEDs are actually showing the boot up process of the firmware in the

transceiver. If none of the LEDs are illuminating at boot up, the LEDs may be in the led

blackout state. If the LEDs are supposed to be in the led normal state, check the

cables you are using, the transceiver is likely not getting adequate power.

4.3. Displaying Receiver Lock Status

The transceiver’s interface can be configured to display status of the receiver, (e.g., the

receiver is in- or out-of-lock with the satellite). The command show receiver status

queries the receiver one time to determine if it is in-lock or out-of-lock. The transceiver

will respond with:

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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Receiver not in lock Indicates that receiver does not have a proper link to the satellite.

Receiver in lock Indicates that receiver has a proper link to the satellite.

Rather than a one-time query, the operator may want to be alerted of changes in real-

time. The command alert receiver lock will instruct the transceiver to display

statements each time the receiver changes lock states. The command to stop the

transceiver from displaying the status of the receiver is ignore receiver lock.

If the receiver is not in-lock, the operator should attempt to move the receiver to a better

position. The parameter to alert or ignore the receiver status is managed by the Host

processor. To make this parameter available after reboot, the client should issue the save

configuration command.

4.4. Measuring Signal to Background Noise

The measure cno command performs a signal (carrier) to noise ratio (C/No)

measurement or measurement of the signal to background noise, using a pilot signal from

the satellite. For this measurement to work, the frequency of the pilot for the proper

satellite and beam must be set in the transceiver.

4.5. Interpreting Signal to Noise Measurement

The command measure cno prompts the user for a Repeat Count. The repeat count

indicates the number of C/No measurements the user wishes to execute. A repeat count

of three or more is recommended. The output of the command will look similar to the

following:

Measuring C/No at 1556060 kHz, please wait...

Frequency = -1812 Hz

Power = 2.78 dB

C/No = 33.88 dB-Hz

The first line of the output shows which C/No frequency the transceiver is using to

measure. Three measurements follow: Frequency, Power, and C/No. Frequency should be

close to 10,000 Hz (+/- 400 Hz). Carrier power is the second measurement. The third and

final measurement is the C/No. A result of greater than 40 dB-Hz indicates the

transceiver is performing as expected.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

5. Troubleshooting

5.1. Purpose of this Section

The purpose of this section is to provide guidance with troubleshooting problems when

integrating the MTM-203 transceiver. The focus of this section is to describe common

error messages and how to systematically verify settings to resolve problems.

5.2. Error Messages

The transceiver will display an error message if an incorrect command has been entered.

An incorrect command is usually a command in which the syntax was wrong or

incomplete. When the transceiver is in API interactive mode and it receives an

incomplete command, it responds with the following message:

Unrecognized command

When the transceiver is in API line mode and it receives an incorrect command, it

provides a standard response in two parts. The first part is the text string “Bad Cmd” and

the second part is the hex equivalent of the characters of the command that the client

attempted to issue.

Example: While in API line mode, the user wants to see a transceiver’s identities.

Rather than issuing the show identities command, the user submits the string “show id”.

The transceiver responds with the following message:

Bad Cmd: "73 68 6F 77 20 69 64"

The following table describes common transceiver error messages.

Table 6: Error messages

Error Message Source of Error

Can't transmit: Receiver not in lock. The transceiver is out of lock and the

transceiver is only permitted to transmit

when the receiver is in lock.

SEND FAILED: Bad or missing TO. The active DSP set does not have a

"Default to" or "Default from" set.

5.3. Troubleshooting the MTM-203

To troubleshoot the MTM-203 Transceiver Module, follow the steps below as applicable

until the transceiver is corrected or you confirm proper functionality.

1. Verify frequency and receiver lock status.

a. Open Hyperterminal. Click Start / Programs / Accessories /

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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Communications / Hyperterminal.

b. Select ComPort.

c. Type show receiver status and press Enter.

d. Verify status for “Receiver in lock”.

e. If receiver is not-in-lock, type list settings.

The following is an example response.

f. Verify the frequency you are using is active.

Note: The last setting displayed in the above example is your active

frequency, “Settings Number: 1”.

g. If your frequency is not “Active”, type edit dsp settings and press

Enter.

h. Type load dsp settings and press Enter.

i. Type the Setting Number that corresponds to desired frequency and

press Enter.

The following is an example response indicating the configuration is

loaded.

Loaded DSP configuration 1.

j. Type activate dsp settings and press Enter.

k. Type save configuration and press Enter.

l. Type reboot and press Enter to reboot the transceiver.

> list settings?

1: Tx 1633585/84375/32 I-R, Rx 1532085/84375/32 I-R, 50, To: 1 (BFIELD), From: 3 (TEST-016)

1: Tx 1633585/84375/32 I-R, Rx 1532085/84375/32 I-R, 50, [Active], To: 1 (BFIELD), From: 3 (TEST-016)

2 is available.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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2. If the frequency setting was correct and/or the receiver showed not-in-

lock, follow these steps.

a. Open Hyperterminal. Click Start / Programs / Accessories /

Communications / Hyperterminal.

b. Type start demod reporting and press Enter.

A response displays asking “Interval?” The “Interval” is a parameter

that indicates the interval (in seconds) that the demod statistics are

displayed.

c. Type 5 to indicate second intervals.

d. Allow demod reporting to run for about one minute.

The following is an example demod report set for 5 second intervals.

5 sec, Eb/No 7.9 dB Quality 193, Frequency Offset 330

5 sec, Eb/No 7.8 dB Quality 193, Frequency Offset 330

5 sec, Eb/No 8.1 dB Quality 193, Frequency Offset 330

5 sec, Eb/No 7.7 dB Quality 193, Frequency Offset 330

5 sec, Eb/No 8.0 dB Quality 180, Frequency Offset -330

5 sec, Eb/No 7.9 dB Quality 195, Frequency Offset 330

5 sec, Eb/No 0.8 dB Quality 64, Frequency Offset 330

e. Type stop demod reporting and press Enter.

f. If an Eb/N0 less than 4.0 is displayed, check the placement of the

antenna. Is something obstructing the view of the southern sky? If so,

move the obstruction or the antenna.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

3. For confirmation of settings, proceed as follows:

a. Type show dsp settings and press Enter.

A list of settings displays. The following is an example display of DSP

settings.

> show dsp settings?

Config Number: 1

Receive Frequency: 1532085000

Receive Chip Rate: 84375

Receive Spread Ratio: 32

Transmit Frequency: 1633585000

Transmit Chip Rate: 84375

Transmit Spread Ratio: 32

Transmit Acquisition Period: 256

Transmit Acquisition Repeats: 1

Transmit Gain: 100

Transmit Auth: 000000

Default From: TEST-016

Default To: BFIELD

C/N0 Frequency: 1556060000

Active VCTCXO: -990

In-Lock Threshold: 30

Out-Lock Threshold: 20

Retry count 4, interval 20

Repeat count 1, interval 5

Repetitions: 1

Freewheel: 180

Scan Dwell: 4000

Config Flags: 000305

Number: 1, Search Step: 40, Search Dwell: 0

Manual Tuning

Lock to Strongest with Acquisition.

Stored VCTCXO: -442

b. Verify settings are correct.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

6. Customer Support Contact Information

If you have questions concerning this document, please contact CMDC’s Customer

Support line at 1-888-428-2101 or send an email to cservice@comtechmobile.com.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

7. Warranty

Comtech Mobile Datacom Corporation is obligated, under the provisions of the Warranty

for items delivered pursuant to specific contracts, to repair or replace or otherwise

provide a remedy for warranted items only if damage or loss results from or is caused by

the warranted item. Comtech is not obligated to provide repair, replacement or other

remedies in the event that damage or loss is the result of or is caused by actions or events

other than the warranted item, to include such causes as (1) misuse or abuse of the item

beyond the use contemplated in the Specification; (2) accidental damage. To include

aircraft crashes; (3) combat damage; (4) natural disasters, to include flood, earthquake,

hurricane, tornado; and (5) fires or explosions not originating on or within the warranted

item.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

This is an unpublished work protected under the Copyright laws.

Appendix A – Specifications

Power Specifications

Power Parameters Specification Maximum Current

VBATT input 6.5 – 15 VDC 2.5 Amp Maximum

Environmental / Mechanical Specifications

Environmental / Mechanical

Parameters Specification

Operating Temperature -40 – 71°C

Storage Temperature -50 – 85 °C

Input/Output (I/O) Specifications

I/O Parameter Voltage Max Current Signaling Comment

Serial Tx 0–3 V 3 V logic

Serial Rx 0–3 V 3 V logic

Serial ground 0 V

RF-A (RHCP) 50 ohm load Max Tx – 4 W

Max noise figure

– 2.0 dB

RF-B (LHCP) 5 ohm load Max Tx – 4 W

Max noise figure

– 2.0 dB

Digital I/O-1 0–3 V 8 mA, max 3 V logic General purpose

I/O

Digital I/O-2 0–3 V 8 mA, max 3 V logic General purpose

I/O

Digital I/O-3 0–3 V 8 mA, max 3 V logic General purpose

I/O

Digital I/O-4 0–3 V 8 mA, max 3 V logic General purpose

I/O

Shutdown 0–5 V High=shutdown 5 V tolerant

input

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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I/O Parameter Voltage Max Current Signaling Comment

Ignition Sense 0-3 V 0 V= ignition

on1

LED-A 0-3 V 5 mA, max 3 V = on LED – “Transmit

On” while

transmitting.

Also lights

during boot. D1

LED on the PC

Board.

LED-B 0-3 V 5 mA, max 3 V = on LED – “Receive

Lock” Software

debounced,

receive in lock

and HDLC in-

sync when lit.

D2 LED on the

PC Board.

LED-C 0-3 V 5 mA, max 3 V = on LED – Console

status flashes

during

configuration

and then stays on

permanently

once configured

and ready. D3

LED on the PC

Board

GPS RF 50 ohm TBD External GPS

Satellite Channel Specifications

Channel

Parameters Return Link Forward Link Comment

KHz from

Center

Frequency

Relative

Carrier

1 This signal is intended to be used with an inverting opto-isolator to monitor a vehicle ignition sense

signal.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

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Channel

Parameters Return Link Forward Link Comment

0.3 -43.0

1.0 -54.0

10.0 -74.0

Transmit

phase noise

100.0 -94.0

Based on a

10° peak

phase noise

value (6.5

degree

average)

Transmit

out-of band 1525.0 and

below -85 FCC part 25

& ETSI

EN301-681

v01.03.02v

Specificatio

Other

emissions FCC Part 15 & 25, ETSI

EN301-681 v01.03.02v FCC &

ETSI

specificatio

Regulatory Compliance

The MTM-203 Transceiver Module has been designed to meet the following FCC and

ETSI compliance standards:

• FCC Part 15 and 25

• ETSI EN301-681 v01.03.02v Specification

• SAJ1113-13, 1455-4.1, 4.9, 4.10, 4.10.3.1

• MIL-STD 810F – High Temp/Low Temp Operation and Storage, Resonance

Survey, Sine-on-Random Vibration, Functional Shock, Crash Hazard Shock,

Bench Handling Shock, Humidity, Temperature Shock, Non-Operational Low

Pressure, Transit Drop Shock

This device has been tested for compliance and certified under FCC Part 25. Any

changes or modifications to the unit not expressly approved by Comtech Mobile Datacom

may void the user’s authority to operate the equipment.

Antennas: Use only the supplied or an approved replacement antenna. Unauthorized

antennas, modification or attachments could cause damage and may violate regulations.

RF Exposure: This unit must be operated with a minimum separation distance of 20 cm

from a person’s body.

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

PROPRIETARY & CONFIDENTIAL

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Appendix B – Mechanical Drawings

Physical Description

This section provides a physical description of the MTM-203 Transceiver Module. This

includes the physical size, location of components, and mounting holes (Figure 4) and a

description of the shield housing (Figure 5).

Figure 4: MTM-203 Transceiver, Top Level Mechanical View 1

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PROPRIETARY & CONFIDENTIAL

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The MTM-203 Transceiver comes with metal upper and lower shields that have tamper

evident seals (see Figure 5). While the shields provide some protection against dust, it is

not intended to have direct exposure to the environment. The MTM-203 module should

be integrated into housing for a larger system.

Figure 5: MTM-203 Transceiver, Top Level Mechanical View 2

Comtech Mobile Datacom Corporation CMDC-DOC-0138, Rev. B

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Glossary

API – Application Programmers Interface

CLI – Command Line Interpreter

CMDC – Comtech Mobile Datacom Corporation

CPU – Central Processing Unit

DDS – Direct Digital Synthesis

FCC – Federal Communications Commission

FPGA – Field Programmable Gate Array

GPS – Global Positioning System

HDLC – High-Level Data Link Control

HPA – High Power Amplifier

IF – Intermediate Frequency

LED – Light Emitting Diode

LH – Left Hand

LHCP – Left-Hand Circularly Polarized

LNA – Low Noise Amplifier

RH – Right Hand

RHCP – Right-Hand Circularly Polarized

RF – Radio Frequency

TCP/IP – Transmission Control Protocol/Internet Protocol

VBAT – Voltage from Battery

Comtech Mobile Datacom CMDCMTM203 L Band Satellite Earth Station User Manual

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