Base station antennas utilize RF transmitters and receivers, which operate with enhanced bias control to achieve very high speed switching during TDD operation. A radio frequency communication circuit for TDD includes a transmit/receive amplifier (e.g., MMIC) having first and second input terminals, which are responsive to a bias control voltage and radio frequency input signal. A bias control circuit is provided, which is electrically coupled to the first input terminal and a current receiving terminal of the transmit/receive amplifier. The bias control circuit includes a closed-loop feedback path between the current receiving terminal and the first input terminal, which is configured to regulate a magnitude of the bias control voltage with high precision to thereby achieve a substantially constant quiescent bias current at the current receiving terminal when the transmit/receive amplifier is enabled.