A Failsafe High Power Transmit-Receive Switch/Limiter MMIC

摘要

The design and performance of a high power Gallium Nitride (GaN) transmit-receive frontend MMIC is presented. The circuit is passive, does not require any external bias voltage and is monolithically compatible with GaN MMIC process technology. High power signals input to the Tx port are directed to the ANT port with minimal insertion loss while the Rx port is isolated and therefore protected from damage. Low power signals input to the ANT port are directed to the Rx port with minimal insertion loss. If the ANT port signal power exceeds some threshold, the circuit starts to limit the power to the Rx port protecting it from damage. Since the circuit does not require an external control voltage it will function normally providing failsafe operation in the event of lost or disconnected Tx/Rx mode control bias. The MMIC results presented here demonstrate 0.7dB of transmit path loss, 1.0dB of receive path loss and 50W power handling over a 3.0-3.6GHz band-width.