UHF downlink-VHF uplink
UHF downlink-VHF uplink full duplex transceiver

UHF downlink/VHF uplink Full Duplex Transceiver

Flight heritage since 2016


CubeSat / small satellite UHF downlink, VHF uplink full-duplex transceiver, adds telemetry and telecommand capability to your mission in a single board. Available in 1200 bps to 9600 bps downlink datarate, and AFSK uplink.

  • Product properties
  • Specifications
  • Documents
  • FAQ
  • Mass: ~ 75g
  • Dimensions: 96 x 90 x 15 [mm]
  • Power: < 4.0W (transmitter on), < 0.480W (receiver only)
  • Interfaces:
    • 104 pin CubeSat Kit stackthrough connector carrying:
      • 6-20V DC power supply
      • I2C bus interface
    • RF input: MMCX 50 ohm
    • RF output: MMCX 50 ohm
  • Operating Temperature: -20 to +60 deg C

UHF transmitter

  • Frequency range: 420-450MHz (Synthesized)
  • Transmit power: Typical 500mW.
  • Modulation:
    • Square Root Raised-Cosine Binary Phase Shift Keying (BPSK) with G3RUH scrambling
    • Gaussian Minimum Shift Keying (GMSK) with G3RUH scrambling
    • Other modulation schemes available upon request
  • Data rate selectable: 1200, 2400, 4800, 9600 bit/s. Other values on request
  • Data protocol: AX.25 or HDLC

VHF Receiver

  • Frequency range: 140-150MHz (Synthesized)
  • Modulation: Audio Frequency Shift Keying, 1200Hz/2200Hz (Bell202)
  • Data rate: 1200 bit/s.
  • -100dBm Sensitivity for BER 10E-5
  • On-board AX.25 frame decoding and integrity checking
  • Data protocol: AX.25 or HDLC

How many output ports are available with these (VHF/UHF) transmitters? For example is it possible to send two modulated telemetries and a beacon through the same card?

The current design has only one RF port intended for UHF downlink transmissions. If more than one RF frequency or RF port is required this would imply more than one card. The device does however offer 4 potential modulation sources to modulate the RF downlink transmission with namely:

1. AX25 Data which can be configured to be telemetry data from the other satellite components or a repetative data beacon.
2. CW or morse code Data which can be configured to be telemetry data from the other satellite components or a repetitive data beacon.
3. A loopback mode where the transmitter is simply retransmitting the audio output from the receiver (assuming a transceiver configuration is used) allowing the device to act as a crossband (VHF up and UHF down) radio repeater.
4. An external modulation input which can be from another modulation source like an other independent modems on the satellite.