A Fully Differential Single-Stage Four-way mmWave Power Combiner for Phased Array 5G Systems

This paper presents design of a fully differential four-way power combiner for receiver phased array applications. Depending on the system requirements several techniques for combining receiving channels from antenna inputs, for example, Wilkinson Power combiners, current summing power combiners and transformer-based power combiners are utilized. In this work, we show a design procedure of a four-way transformer based current summing power combiner with wideband response from 23 and 45 GHz frequencies. A single stage power combiner shows a simulated insertion loss of 1.5 to 3 dB, compared to Wilkinson power combiner’s loss of 3.6 to 6 dB. Isolation between the channels is -14 dB. The proposed combiner and Wilkinson combiner consume area of 0.101 mm² and 1.034 mm², respectively. Both combiners are designed using 45 nm CMOS SOI process technology.