SMALL AREA AND LOW POWER IIR FILTER STRUCTURE

摘要

Embodiments of the present disclosure provide a digital filter module for use in receivers, particularly suitable for use in a narrow-band electromagnetic receiver. Design of the module is based on a recognition that providing to the module samples of a signal received by a receiver and sampled at a sampling frequency equal to four times the intermediate frequency of the receiver, eliminating zeros in the filter, and implementing the filter module as a resource-shared second-order filter structure that includes two sections advantageously enables saving some hardware components, particularly some multipliers and adders, in implementing a versatile digital filter module that can function either as two real filters or one complex filter. In this manner, substantial reduction of area and power consumption of the filter module may be achieved, while maintaining sufficiently high filtering performance.

主权项

1. A digital filter module for filtering digital samples of a signal received by a receiver, the filter comprising:
a resource-shared, at least second-order, filter structure comprising a first section and a second section,
the first section configured to receive digital samples representing real parts of the signal received by the receiver, andthe second section configured to receive digital samples representing imaginary parts of the signal received by the receiver,the resource-shared second-order filter structure configured to operate, in a first mode, as an all-pole complex infinite impulse response (IIR) filter, and, in a second mode, as two real all-pole IIR filters; and a controller configured to set a mode of operation of the resource-shared second-order filter structure to the first mode or the second mode, wherein the digital samples received by the first section and the digital samples received by the second section are sampled at a sampling frequency equal to four times an intermediate frequency of the receiver.