Testers & Simulators

Inmarsat-C Physical Layer Tester (CPLT)

Inmarsat-C Physical Layer Tester (CPLT)

Square Peg Communications Inc.’s Inmarsat-C Physical Layer Tester (CPLT) is a software application that runs on the generic high-rate Physical Layer Tester (PLTH) platform. The CPLT supports testing of the physical layer performance and protocol implementations of Inmarsat-C Mobile Earth Stations (MESs) and Land Earth Stations (LESs).

The CPLT supports all of the Inmarsat-C2 channel types using DSP-based modem technology. An Ethernet interface allows various options for control of the CPLT or for control of external equipment by the CPLT. A serial interface is also provided to allow communication with an MES under test.

The CPLT is a powerful and flexible test tool. A familiar Windows-based user interface provides easy access to test functions, while a powerful scripting language allows every feature of the CPLT and equipment under test to be exercised in automated test cases and suites.

The CPLT also provides a Test Sequencer user interface compatible with that used with legacy Inmarsat-C test equipment. This facility allows users to execute existing type approval RTP scripts, while the channel simulator and signal analysis facilities provide the means of demonstrating compliant physical layer performance.

Transmit Capabilities

Physical channels3 simultaneous (optional 4th channel) 
Channel typesTDM (1200 sym/s BPSK)
SIG (600 / 1200 sym/s BPSK)
MSG (600 / 1200 sym/s BPSK)
Test tones (CW, two-tone, etc.)
Channel impairments

Independently-specifiable parameters:

  • Fixed carrier frequency error, burst frequency jitter
  • Doppler rate, peak offset
  • Reacquisition carrier offset
  • Adjacent channel interference level and frequency offset
  • Co-channel interference level
  • Continuous phase noise spectrum, level
  • Discrete phase noise level and freq offset
  • Fading model, bandwidth, C/M ratio
  • Phase and/or amplitude jump distribution, magnitude, interval
  • Transmission path delay, burst timing jitter
  • Symbol rate error
  • HPA non-linearity
  • AWGN

Receive Capabilities

Physical channels3 simultaneous (optional 4th channel)
Channel types

TDM (1200 sym/s BPSK)
SIG (600 / 1200 sym/s BPSK)
MSG (600 / 1200 sym/s BPSK)

Signal analysisSignal capture (raw samples and soft decisions)
Selectable pass/fail limits for measurements:
  • Carrier frequency offset
  • Average power, power rate of change
  • Phase change
  • Integrated phase noise
  • Burst timing offset
  • Symbol clock rate error
  • Constellation mean-squared error, EVM
  • Eb/No loss
  • Uncoded errors
  • Power profile
  • Spectral shape
  • Out-of-band emissions
  • Phase noise spectrum

Ethernet Interface Capabilities

FunctionalityRemote control interface (e.g., to LabView™ or Windows remote desktop)
GPIB (IEEE-488) interface (with Ethernet-to-GPIB converter)

Logging Capabilities

GeneralTest Sequencer interface messages
Transmitted/received packet data
Test sequence progress and outcome
System events, faults, and abnormal conditions
Signal analysisSignal analysis measurements
Signal analysis statistics
Raw input samples
Demodulator soft decisions

Script Capabilities

GeneralProcedure-based (like Basic, C or Pascal)
Functions for string processing, math, user interaction, logging, I/O (serial, TCP/IP, GPIB)
Integrated development environment
CPLT-specificConfiguring and controlling modems
Sending and receiving Inmarsat-C packets
Controlling channel simulator
Sending and receiving messages to simulate the Test Sequencer
CPLT Configuration for MES Testing
(Not all components are required for all test applications)

Physical Layer Tester (PLT-H)

  • Requires MSS L-band Radio Frequency Unit (RFU) for operation at L-band

Physical Layer Tester (PLT-L)

MSS L-band Radio Frequency Unit (RFU)

ATC Interface Unit (AIU)

Square Peg Communications Inc.
4017 Carling Avenue, Suite 200 
Ottawa, ON, Canada K2K 2A3
Tel + 1 613 271 0044
Fax+ 1 613 271 3007
Contact us for more information: