Fast and highly accurate RF phase detector with analog integrator for APAA system

An RF phase detector employing an analog integrator is proposed for active phased array antenna system. The RF phase detector, consisting of an analog integrator, a mixer and a divider can realize both fast and highly accurate detection at the same time. By setting the integral time of the analog integrator as integral multiple of the half cycle of RF signal, the variation of output voltage due to second harmonic of the mixer output can be prevented. The proposed RF phase detector is fabricated in 0.18μm SiGe-BiCMOS process. It is achieved that the measured accuracy of phase detection is 0.52 deg.-rms in the detection time of 8ns at 1GHz.