Simplified implementation of millimetre‐wave zero‐bias detector for an accurate detection in six‐port‐based receivers

Abstract

In this Letter, a simplified design approach for zero-bias power detectors suited for integration in six-port receiver architectures is presented. The proposed concept uses the quadrature hybrid coupler as an effective way to improve the input impedance matching and linearity performance. The proposed solution has been experimentally validated through its implementation into a 60 GHz six-port receiver prototype to investigate its performance in detecting various M-ary quadrature amplitude modulation (M-QAM) signals. The obtained measurement results show a high accurate and linear detection responses for all investigated M-ary QAM modulation techniques (4-QAM, 16-QAM, 32-QAM). The variation in the error rates of the demodulated signals at the adjacent differential outputs is minimal (<1%), and the maximum error rate achieved does not exceed 5%. The obtained precision and linearity performances make the proposed structure highly suitable for the emerging millimetre-wave six-port receiver front-ends.