Patent ID: 6546408
Filing Date: 2003-04-08
Classification: H03H

Abstract:
A sinc filter comprising:a register to store digital data and to partition the digital data into at least two symmetrical multibit words and at least two partial words at the extreme ends of said register, wherein the two partial words are to be combined into a single word for processing; a memory coupled to the register to store output values, the output values are partial sums of at least two product terms wherein each product term is a product of one of a plurality of numeric values of a symmetrical multibit word and a respective one of a plurality of filter coefficients, and a given partial sum is constructed from less than all products terms; a look-up logical circuit coupled to the memory wherein the output values corresponding to a first word of the at least two symmetrical multibit words are looked up in the memory according to a first memory address formed by the numeric values of the first word, and the output values corresponding to a second word of the at least two symmetrical multibit words are looked up according to a second memory address formed by reversing the bit-order of the numeric values of the second word and referencing the output values corresponding to the reversed bit-order numeric values; and a summing circuit to sum the output values from the look-up logical circuit to provide a filter output.