A 24 - 30 GHz Ultra-Compact Phase Shifter Using All-Pass Networks for 5G User Equipment

This work presents a 24-30 GHz phase-shifter with 0.028 mm2 of area for 5G mobile applications. The small size is achieved by employing variable-phase all-pass networks, which enables the embedding of switches within all-pass networks when implementing switched-type phase-shifters. The proposed PS was implemented and manufactured using 0.25 um BiCMOS. Measurements were performed, showing an insertion loss of 4.49 +- 0.27 dB at 27 GHz, an RMS gain error below 0.5 dB and an RMS phase error below 7 degrees across the whole frequency band.