A 35‐GHz high image rejection resistive mixer using a tunable resonator and a narrowband bandpass filter

Abstract

AbstractA 35‐GHz high image rejection resistive mixer (IRM) is implemented using a tunable resonator and a narrowband bandpass filter (BPF). To obtain a high image rejection ratio (IRR) of more than 40 dB, a tunable resonator, which consists of inductive lines and varactors, is integrated inside a mixer. It can not only mitigate the mismatch of the resonating frequency through process variation and the parasitic effect but also be used as a radio frequency input matching circuit. A narrowband BPF based on coupled slow‐wave resonators is inserted before a mixer. The proposed IRM is fabricated by a commercial 0.15 μm gallium arsenide (GaAs) pseudo high electron mobility transistor (pHEMT) monolithic microwave integrated circuit process. The proposed IRM represents 42.2 dB IRR, a conversion loss of 11.6 dB, an input 1‐dB compression point (P−1dB) of more than 8 dBm, and a 35 dB local oscillator‐radio frequency isolation at 35 GHz.