DESIGN OF IMAGE REJECTION MIXER FOR APPLICATION IN X-BAND RF TRANSCEIVERS

Abstract

An image rejection mixer (IRM) based on the Hartley structure is designed for application in X-band RF transceivers. This mixer includes a high-resolution digital attenuator and coupler to combine the functionality of phase shifting and attenuating. Hence, it can perform phase and gain corrections, I/Q imbalance reduction in the mixer. The 90 degrees 2-section hybrid coupler is used to meet the requirements of bandwidth and I/Q signal balance. The simulation results of the proposed IRM in the frequency band of 9.1÷9.7 GHz with the intermediate frequency of 90 MHz, bandwidth of 10 MHz show that the image rejection ratio (IRR) of more than 36 dB was achieved.