This flight-proven S-band subsystem integrates transmit power amplification, low-noise receive amplification and dual cavity passband filters, supporting 5G narrowband IoT, NR-NTN networks and CubeSat and SmallSat communications as one qualified item rather than an assembly of discrete parts. Filtering is what allows a 10 W transmitter and a sensitive receiver to coexist 120 MHz apart. Transmit rejection is 50 dB minimum at 2035 MHz and 40 dB at 2300 MHz; receive rejection is 55 dB at 1890 MHz and 85 dB at 2155 MHz. Transmit gain is 54 dB typical delivering 36 dBm minimum at 64QAM and 40 dBm minimum at BPSK, and receive gain is 30 dB typical at 1.5 dB noise figure. I2C temperature monitoring, independent transmit and receive enable lines and a fault status pin make the module addressable from the flight computer. Supply is 27 to 29 VDC drawing 0.9 A maximum at 64QAM and 1.45 A at BPSK. The module is 100 x 95 x 50 mm (3.92 x 3.74 x 1.98 in) at 587 g with SMA female interfaces, shock tested to ECSS-E-ST-10-03C and temperature cycled -30 to +65 °C. Typical lead time for standard configurations is 8 to 10 weeks.