Phase calibration techniques for injection-locking LO-path based phase-shifting phased-array architectures

Experimental results of phase calibration techniques are reported for a ninth subharmonic injection locking LO-path based phase-shifting phased-array architecture in 130 nm CMOS technology operating in the K-band. The proposed calibration means employ the DC weights of a ninth-subharmonic cartesian phase-shifter, the Q-tuning of and the injection strength into a negative-gm oscillator to fine-tune the output phases of two 21GHz oscillators. The sensitivities of these calibration techniques are analyzed and further contrasted through experimental measurements at 21.51GHz. The impact of the adopted calibration techniques on the phase noise performance is also reported.