A direct-conversion mixer with DC-offset cancellation for IEEE 802.11a WLAN receiver - Oimins Xu; Xueqing Hu; Pens Gao; Jun Yan; Yin Shi; Foster F. Dai; Richard C. Jaeger (International Symposium on Circuits and Systems (ISCAS 2006), 21-24 May 2006, Island of Kos, Greece, 2006)