A member of the RT Logic Telemetrix® product line, the Telemetrix 400 Real Time Channel Simulator (T400CS) addresses a broad range of IF and RF hardware-in-the-loop R&D, test, operational, and training applications. The T400CS creates RF and IF signals that precisely match those that occur when transmitters and receivers are in motion with respect to one another. By accurately duplicating the effects of motion and RF channel physics on an RF link, the T400CS allows bench testing of what once required actual motion and distance between a transmitter and receiver.

The T400CS enables comprehensive test and training activities without actual flights of the satellites, missiles, UAVs, targets and aircraft carrying the transmitters or receivers under test. T400CS channel effects include physics-compliant, phase-continuous, real-time, carrier and signal Doppler shift, range delay, range attenuation, fading, and noise. In addition, multiple test and/or interference signals can be generated with the optional multi-channel signal source. A comprehensive selection of RF up-converters and down-converters are also available, allowing signals to be generated or received in frequency bands of interest.

The T400CS client/server software architecture facilitates a wide range of local and remote control options. Local control is provided by an easy-to-use RT Logic Graphical User Interface (GUI). Users can also create their own channel simulation profiles from a comma separated listing of RF effects values versus time. Programmatic control capabilities include a well documented control protocol and an optional RT Logic Plug-in for the Analytical Graphics Inc. (AGI) STK software. This provides a seamless real-time connection between the motion and RF modeling included in STK, and T400CS real-world, hardware-in-the-loop creation of fully physics compliant channel effects.

The T400CS is a general purpose RF and IF test and measurement instrument for communications system- and component-level testing and verification, both in the laboratory and in the field. Key applications include a wide variety of flight and ground system testing of satellites, UAVs, aircraft, missiles and ground stations.

The RT Logic T400CS generates physics-compliant, phase-continuous, real-time carrier and signal Doppler shift, range delay, range attenuation, and Additive White Gaussian Noise (AWGN). These effects can be applied singly or in combination. Together they precisely duplicate propagation effects encountered in LEO, MEO, HEO and GEO satellite applications, as well as aircraft, UAV, missile, target and range test scenarios.

The T400CS is designed to be user-expandable, allowing the system to cover a wide range of channel counts and frequencies. One channel simulator card is typically configured in a T400CS system in order to emulate a single communication path, for example, an uplink or a downlink path. This same configuration can also be used for a single direction or half duplex up and downlink path if emulating a link through a "bent pipe" satellite transponder. When emulating a bi-directional or full duplex communication link, the T400CS system is typically configured with two channel simulator cards. Signal recorders/players, signal generators and spectrum analyzers can also be included in the T400CS system, further expanding its testing capabilities.

The T400CS can be inserted into a system under test in multiple ways, including direct cabling or utilizing amplifiers, signal conditioners and antennas connected over the air. The T400 Channel Simulator is an important addition to any communication system designerís test bench, with flexibility that reaches much further to quality assurance and training.


  • Instantaneous bandwidth, 40 MHz or 85 MHz (model dependant)
  • Signal Doppler shift, 0 kHz ±500 kHz, phase-continuous, 1 Hz resolution
  • Carrier Doppler shift, 0 kHz ±20 MHz or 0 kHz ± 42.5 MHz (model dependant), phase-continuous, 1 Hz resolution
  • Range delay, 3 μs to 2.5 s or 3 μs to 1.25 s (model dependent), phase-continuous, 1 ns resolution
  • Fading/range attenuation, up to 60 dB, phase-continuous, 0.5 dB resolution
  • AWGN, -168 dBm/Hz to -102 dBm/Hz
  • Receiver noise, -168 dBm/Hz to -102 dBm/Hz
  • Amplitude response, ±0.5 dB
  • Instantaneous dynamic range, 60 dB
  • Internal and external trigger
  • Input Bands, Intermediate Frequency (IF), 70/160/266 MHz, RF input/output frequencies (with optional converters) UHF-band, L-band, S-band, C-band, X-band and Ku-band
  • Compatible with most non-RT Logic 70/160/266 MHz IF converters
  • Signal Generation (with optional signal generator cards)
  • Channels, eight (8) per card
  • Standard modulation types: BPSK, QPSK, OQPSK, SOQPSK-TG, SOQPSK-MIL 8PSK, MSK, FSK, AM, FM, CW
  • Data rates, modulation type dependent
  • Frequency offset, 0 kHz ±20 MHz or 0 kHz ±42.5 MHz (model dependant).

RT Logic,
Colorado Springs, CO
(719) 598-2801,
RS No. 303