题目/Title：Power-Scalable, Complex Bandpass/Low-Pass Filter With I/Q Imbalance Calibration for a Multimode GNSS Receiver

作者/Author：徐阳,池保勇,俞小宝,祁楠,Partick Chiang,王志华
                        Yang Xu,Baoyong Chi,Xiaobao Yu,Nan Qi,Partick Chiang,Zhihua Wang

期刊/Journal：IEEE Transactions on Circuits and Systems II-Express Briefs

年份/Issue Date：2012Jan.

卷（期）及页码/Volume（No.）&pages：Vol.59, No.1, pp. 30 - 34

摘要/Abstract：
A power-scalable reconfigurable filter with I/Q imbalance calibration for a multi-mode GNSS receiver is presented. The filter is reconfigurable as either a 5th-order complex-bandpass filter exhibiting a tunable IF frequency (4.092MHz, 6.138MHz, 10.23MHz, 12.296MHz, 13.29MHz, 18.4MHz, 20.442MHz) and bandwidth (2.2MHz, 4.2MHz, 8MHz, 10MHz, 18MHz), or a 3rd-order lowpass filter with tunable bandwidth (5MHz, 9MHz). A flexible current-reuse op-amp with power-scaling technique is proposed to lower the power consumption, and the image rejection ratio is improved by almost 20dB by introducing an I/Q imbalance calibration circuit before the filter. The filter, implemented in 65nm CMOS, consumes 2.9mW to 19.5mW in different modes, with the I/Q calibration circuit consuming 0.9mW.