Design of Ku-Band Bi-Directional Wideband Active Phase Shifter Using Reconfigurable Network

This paper presents a 6-bit bi-directional active phase shifter in the 55-nm CMOS technology for Ku-band phased arrays. Two switchable polyphase filters (PPFs) and a bidirectional variable amplifier (VGA) is adopted to achieve the bidirectional phase shifting. To obtain the wideband asymmetric impedance matching, reconfigurable networks are used between the switchable PPF and the bi-directional VGA. The bidirectional phase shifter achieves the 6-bit phase shifting with the RMS gain error ranges from 0.2 dB to 0.5 dB, and the RMS phase error ranges from 1.2° to 2.6°. The average gain ranges from -4 dB to -1 dB with a current consumption of 28 mA from a 1.2 V supply voltage.