Design of Ka-band reflection-type analog electrically controlled phase shifter

In order to modulate the phase of RF signal continuously, a new miniaturized Ka-band analog electrically controlled phase shifter is presented. The phase shifter based on 90 directional coupler and parallel variable capacitance diodes(VCD) achieves matching circuits and shift phase, and the circuit can gain wide range of phase shift by changing the bias voltage of variable capacitance diodes(VCD). At the same time, insertion loss fluctuations have a significant improvement by parallel compensation resistance. Simulation and experimental results show that the phase shifter obtains 180 phase shift, the insertion loss is less than 6.5 dB, the insertion loss fluctuations are within 1 dB, and the phase shift errors are less than 10 in 29-31 GHz range.