@article{FENG2006, 
author = {Dong FENG and Bingxue SHI},
title = {Linear-in-dB Variable-Gain Downconversion Mixer for Zero Intermediate Frequency Receivers},
year = {2006},
journal = {Tsinghua Science and Technology},
volume = {11},
number = {1},
pages = {8-11},
keywords = {wireless local area network (WLAN), automatic gain control (AGC), complementary metal-oxide semiconductor (CMOS), ladder circuits, mixer noise, zero intermediate frequency (ZIF)},
url = {https://www.sciopen.com/article/10.1016/S1007-0214(06)70147-X},
doi = {10.1016/S1007-0214(06)70147-X},
abstract = {In-phase/quadrature (I/Q) mismatch is a key problem in zero intermediate frequency (ZIF) receiver architectures. Although integration and careful layout can alleviate I/Q mismatch, circuit and system level calibrations are also needed due to process variations and variable operating conditions. The amplitude imbalance between I/Q channels was calibrated using a modified R-2R ladder to achieve fine linear-in-dB variable gain. A downconversion mixer working in the 2.4-GHz band was developed for a wireless local area network (WLAN) ZIF receiver using 0.25-µm complementary metal-oxide semiconductor (CMOS). The two-stage mixer configuration relaxes the tradeoff between noise and linearity. Experimental results verify the fine linear-in-dB variable conversion gain of the mixer, which can also be used as part of an automatic gain control (AGC) loop.}
}