Pipelined Recursive Residue Number System Digital Filter
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
A technique is described whereby pipelined recursive digital filters achieve high throughput rates through the use of read-only memory (ROM) table look-up techniques, based on the residual number system (RNS). Although prior art has established the use of ROM table look-up techniques based on RNS for non-recursive digital filters, such as the finite impulse response (FIR) filter, pipelining has been less successful for infinite impulse response (IIR) filters. This is because the IIR filter requires feedback of the output signal which causes an inherent delay and this determines the sampling rate of the filter. This delay is generally five or more table-look-up times slower, making the IIR filter five times slower than an equivalent FIR filter.