AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS, cilt.128, 2021 (SCI-Expanded)
This paper presents a novel tunable method to improve the image rejection ratio in image-reject down-converters. The proposed technique is based on the phase equalization and amplitude error mitigation through proper biasing of mixers. With the aid of the proposed technique, amplitude, and phase imbalances, resulting in unwanted images, were minimized. Therefore, significant improvement in the image rejection ratio was attained without using complex filter banks. Phase equalization is accomplished by introducing a delay line to force the phase error to be zero at the center of the frequency band.