An Active-RC Complex Filter with Mixed Signal Tuning System for Low-IF Receiver

—An active-RC complex filter synthesized from leapfrog low-pass prototype is proposed in this paper, which is less sensitive to components values variation comparing with the common used cascade-pole method. Furthermore, a mixedsignal tuning system was implemented to make the RC time constant stable, and can be turned off after the completion of tuning. The filter was implemented in 0.18µm CMOS process. It is centered at 4MHz with 2MHz of bandwidth. It has the voltage gain of about -2dB, the image rejection ratio of about 28dB, the output 1-dB compression voltage of 0.39V, the inband integral output noise of 32µVrms, and the power consumption of 6.1mW. The filter can be used in the low-IF GPS receiver.

• Type: Conference
• Year: 2006
• Where: APCCAS
• Authors: Dingkun Du, Yongming Li, Zhihua Wang, Seeteck Tan
• Keywords: Active-RC Complex Filter, APCCAS 2006, Components Values Variation, Hardware, Leapfrog Low-pass Prototype