Full 360$^{\circ }$ Vector-Sum Phase-Shifter for Microwave System Applications

Abstract

An innovative vector-sum phase shifter with a full 360° variable phase-shift range is proposed and experimentally demonstrated in this paper. It employs an active balun and a very high-speed CMOS operational transconductance amplifier (OTA) integrator to generate the four quadrature basis vector signals. The fabricated chip operates in the 2-3 GHz, it exhibits an average insertion gain of 1.5 dB at midband, and has an RMS phase error below 5° over the measured frequency span. The chip consumes 24 mW of DC power and is highly compact, measuring only 0.38 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> including bonding pads.