The designs of transmit/receive module for X-band navigation system

This paper is concerned with some versions and measurements of the X-Band Transmit/Receive (T/R) module that is a key unit of the active phased array antenna (APAA). In the first version (V1), the transmit chain (TX) is primarily composed of a medium power amplifier and a two-watt-output power amplifier, and the Receive chain (RX) includes a low noise amplifier (LNA), and an attenuator (AT). In the second version (V2), an analog phase shifter is added to the transmit chain (TX), along with a medium power amplifier, as well as temperature controlling circuits. In the Receive chain (RX) a phase shifter (PS) and a LNA with voltage gain amplifier (VGA) are added, but the AT is removed. Thanks to this improvement, the T/R module achieved 31 dBm minimum P1 dBc with 30 dB linear gain in TX, 32 dB linear gain and with 5.1 dB noise figure in RX, with dynamic range of at least 95 dB. With both versions, the focus of mechanical designing is to reduce effects from noise and rising temperature.