A Fast and Precise Blind I/Q Mismatch Compensation for Image Rejection in Direct‐Conversion Receiver. Issue 1 (1st February 2014)

• Record Type: Journal Article
• Authors: Kim, Suna; Yoon, Dae‐Young; Park, Hyung Chul; Yoon, Giwan; Lee, Sang‐Gug
• Is Part Of: ETRI journal. Volume 36:Issue 1(2014)
• Page Start: 12
• Page End: 21
• Publication Date: 2014-02-01
• Subjects: Image rejection -- I/Q gain mismatch -- I/Q phase mismatch -- DC offset -- direct‐conversion receiver -- DCR -- low‐IF -- zero‐IF -- LMS algorithm -- adaptive step size; Telecommunication -- Periodicals; Electronics -- Periodicals; Electronics; Telecommunication; Periodicals; Periodicals; 621.38205
• DOI: 10.4218/etrij.14.0113.0320
• Languages: English
• ISSNs: 1225-6463

Abstract

Abstract : In this paper, we propose a new digital blind in‐phase/quadrature‐phase (I/Q) mismatch compensation technique for image rejection in a direct‐conversion receiver (DCR). The proposed image‐rejection circuit adopts DC offset cancellation and a sign‐sign least mean squares (LMS) algorithm with a unique step size adaptation both for a fast and precise I/Q mismatch estimation. In addition, several performance‐optimizing design considerations related to accuracy, speed, and hardware simplicity are discussed. The implementation of the proposed circuit in an FPGA results in an image‐rejection ratio (IRR) of 65 dB, which is the best performance with modulated signals, along with an adaptation time of 0.9 seconds, which is a tenfold increase in the compensation speed as compared to previously reported circuits. The proposed technique will be a promising solution in the area of image rejection to increase both the speed and accuracy of future DCRs.