WR-3.4 Band Reflection-type Phase Shifters
This paper presents two WR-3.4 reflection-type phase shifters (RTPS), i.e. RTPS1 and RTPS2, using in a 250-nm InP double heterojunction bipolar transistor (DHBT) process. The proposed RTPSs adopt a compact broadside-coupled line coupler as a 90° hybrid coupler. In addition, the average loss variation is reduced by optimizing the impedance of coupled-line coupler and the reflective load. The RTPS1 achieves a 180° phase shift with an average insertion loss of 3.5 to 7.9 dB while maintaining loss variation less than 1.7 dB. The RTPS2 exhibits a full 360° phase shift using a triple-resonance load. The chip size including all probing pads is as small as 372 x 458 μm2. The dc power consumption is zero.