Sorry, you need to enable JavaScript to visit this website.
Skip to main content

Satellite Communications Transponder (CXS-2000)

The CXS-2000/C is the high-reliability U.S. Department of Defense (U.S. DoD) standard for programs requiring both SGLS and Unified S-Band (USB)-compatible transponders and provides Telemetry, Tracking and Command (TT&C) between U.S. Air Force satellite control facilities and military satellites. The CXS-2000/C transponder builds upon L3Harris T&RF’s strong flight heritage and continues the tradition of meeting high-reliability and radiation-hardening mission requirements with more than 100,000 hours of successful on-orbit operation.

The CXS-2000/C is a TRL-9 design, currently in orbit on several successful programs. The CXS-2000/C implements a space-qualified, radiation-hardened FGPA based design to provide a fully configurable architecture while maintaining a reduced mass, power consumption, footprint and improved performance. The CXS-2000/C can be provided either with embedded encryption and decryption, or compatible with external encryption devices such as L3Harris T&RF’s MCU-110B.

The transponder operates directly at L- and S-Band, with ranging, coherency, convolutional encoding, direct modulation, BPSK and subcarrier modulation all offered as standard features. A 1553 interface for commands and telemetry is also available within the same mechanical envelope.


  • Dual-band USB and SGLS transponder
  • NSA certified Type-1 design
  • Embedded encryption with optional decryption
  • Multimode modulation in PM, FSK, AM, BPSK and optional QPSK
  • Flight proven
  • High reliability, radiation hardened
  • 15-year mission life
  • Triplexer (optional)

CXS-2000 Specifications

Download the CXS-2000 Spec Sheet
Receive frequency 1.76 – 1.84 GHz 2.025 – 2.120 GHz 1.9325 GHz
Carrier tracking rate/range 10 kHz/sec, ± 100 kHz
Carrier acquisition
Threshold (with modulation) -113 dBm -119 dBm -80 dBm
Acquisition time
With modulation 0.8 s maximum 1.2 s maximum 20 s maximum
Search mode only 20 s maximum NA Search mode only
Noise figure 3.5 dB maximum 5 dB maximum
Ranging channel
Type PRN or tone NA
Delay 3.5 μsec NA
Delay variation ± 120 nsec NA
Turnaround ratio 1:1 NA
Command channel
Modulation types AM/FSK/PM BPSK/PM BPSK/3.1 MHz subcarrier
Modulation index 1.0 radians 1.0 radians 1.57/1.0 radians
PM subcarrier frequency NA 16 kHz 3.1 MHz (optional)
FSK tone frequencies 65, 76, 95 kHz NA NA
Data rate 1 or 2 kbps 1, 2 or 4 kb 32 or 64 kbps
Threshold (10 -6 BER) -110 dBm (2 kbps) -113 dBm (2 kbps) -82 dBm
SGLS & USB Direct BPSK modulation data rates to 1 Mbps NA
Output data interface
Outputs (RS422 or LVDS) "S", "0", "1", clock, data clock, ramp lock, CDU lock NA
Transmit frequency -2200 to 2300 MHz
Coherent turnaround ratio 256/205 (SGLS) 240/221 (USB) NA
Frequency stability ± 20 ppm
RF power 5 W minimum, 8 W option, low power port (-5 dBm)
Output protection No damage; open or short circuit
IPM (100 Hz to 1 MHz) < 2° rms (ambient) non-coherent, < 3.5° rms coherent
IAM < 2%
Telemetry channel
Peak phase deviation 3 radians maximum
Subcarrier frequencies 1.024
Subcarrier stability ± 0.005%
Direct carrier modulation rates 8 Msps (NRZ) maximum
Subcarrier modulation rates 128 kbps maximum
Downlink forward error correction (FEC)
Encoding Rate 1/2 convolutional encoding rate 7/8 reed-solomon
Input data interface
Device type RS-422 or LVDS
Power Requirements
Input voltage +28 VDC or +70 VDC
Receive only 12 to 16 W maximum
Transmit and receive 6 to 56 W maximum
Over/reverse voltage Omnidirectional
Current limiting 50 watts
Command inputs 28 V latching relay, serial interface
Temperature (qual) +28 VDC or +70 VDC
Vibration 15 Grms
Altitude Unlimited
EMI MIL-STD-461F (tailored)
Radiation 100 krads (chassis), >25krads (part)
Serial interface for command and/or telemetry data.
*Power consumption and weight varies with options selected
If you are seeking a quote for parts, please include a CAGE code. This will help us serve you faster.

Related Domains & Industries

Solutions that solve our customers' toughest challenges.
view all capabilities