An Q-factor calibration method for compensation of the I/Q signal imbalances in 5-6 GHz beamforming receiver

作者：Jung Won Jae^*; Hong Nam Pyo; Jang Jong Eun; Kim Jin Sup; Park Jun Seok

来源：Microwave and Optical Technology Letters, 2018, 60(9): 2272-2276.

DOI：10.1002/mop.31329

• beamforming
• IQ network
• phase shifter
• phased array
• vector modulator

This article presents 5-6 GHz beamforming receiver with Q-factor calibrated vector modulator to reduce phase error and amplitude mismatch. Q-factor of vector modulator IQ network has to be 0.95-1.05 in 5-6 GHz to get under +/- 3 degrees phase error. Proposed Q-factor calibration circuit selects the best capacitance and resistance for proper Q-factor in desired frequency range. Beamforming receiver prototype, which is implemented in 0.13-m CMOS, has 0.98-1.03 Q-factor in 5-6 GHz. The prototype has improved performance than without calibration: its rms phase error is maximum 1.5 degrees (4.5 degrees improved), and amplitude mismatch is maximum 0.47 dB (0.73-dB improved). In addition, noise figure is 3.8-4.6 dB at 5-6 GHz.

• 出版日期2018-9