A digital multistandard reconfigurable FIR filter for wireless applications

This paper presents a fully reconfigurable 26-tap low- power TDF (transposed direct form) interpolator FIR (Finite Impulse Response) digital filter with 9 input bits and 8 output bits, designed in 0.13-μm CMOS technology to be embedded in a multistandard wireless transmitter. The choice of 9-bit multiplier coefficients allows us to satisfy the specifications of WLAN (wireless local area network), UMTS (universal mobile telecommunications system), and Bluetooth standards, with no need for any hardware reconfiguration. An internal digital signal processor allows us to meet other custom filter specifications by simply loading different multiplier coefficients, with the only constraint of the number of taps. Simulations showed a total power consumption of ~5mW in the WLAN case, of 1 mW in the UMTS case, and an EVM (error vector magnitude) of ~1.9% and ~1.5%, respectively which allows error correction in the receiver.