Patent ID: 7904035

Claim:
A radio frequency (RF) communications device comprising: a first antenna port coupled to a signal line; a second antenna port; a first output stage circuitry coupled between the signal line and the second antenna port; a transmitter circuitry configured to generate a calibration signal and an RF output signal, the transmitter circuitry having a second output stage circuitry configured to output the calibration signal on the signal line in a calibration mode of operation, and the second output stage circuitry configured to output the RF output signal for broadcast on the signal line and across either the first antenna port or the first output stage circuitry and the second antenna port subsequent to the calibration mode of operation; a tuning circuitry coupled to the signal line and configured to receive the calibration signal; and a controller configured to adjust a signal level of the calibration signal generated by the transmitter circuitry and a tuning of the tuning circuitry during the calibration mode of operation; wherein the transmitter circuitry, the second output stage circuitry, the tuning circuitry, and the controller are at least partially integrated on the same integrated circuit, wherein the first output stage circuitry presents a first impedance to the second antenna port, and wherein the second output stage circuitry presents a second impedance to the first antenna port that differs from the first impedance.