Development of multiband phase shifters in 180-nm RF CMOS technology with active loss compensation

We present the design and development of a novel integrated multiband phase shifter that has an embedded distributed amplifier for loss compensation in 0.18-μm RF CMOS technology. The phase shifter achieves a measured 180° phase tuning range in a 2.4-GHz band and a measured 360° phase tuning range in both 3.5- and 5.8-GHz bands. The gain in the 2.4-GHz band varies from 0.14 to 6.6 dB during phase tuning. The insertion loss varies from -3.7 dB to 5.4-dB gain and -4.5 dB to 2.1-dB gain in the 3.5- and 5.8-GHz bands, respectively. The gain variation can be calibrated by adaptively tuning the bias condition of the embedded amplifier to yield a flat gain during phase tuning. The return loss is less than -10 dB at all conditions. The chip size is 1200 μm×2300 μm including pads.