A 2.6 MHz Bandwidth, 3rd/5th Order Active-RC Polyphase Filter with Quadrature Offset Cancellation for Low-IF GPS Radio

In this paper a low power active-RC filter exhibiting a reconfigurable transfer function, 3
^rd
/5
^th
order Butterworth, integrated in a low IF GPS receiver and fabricated in 0.35um SiGe BiCMOS technology is presented. This 17/26 dB gain filter has a bandwidth of 2.6MHz which is centered at 4.1MHz. It drains 1/1.25mA from a 2.7V supply in 3
^rd
/5
^th
order modes. The average in-band image rejection of this 0.58 mm
²
filter is better than 25dB. This trimmed filter employs a quadrature offset cancellation circuit to remove all the available offset coming from the mixer output and its own mismatches.