Ultra narrowband filtering with Prism signal processing: Design and simulation

Abstract

Prism signal processing is a new FIR filtering technique offering a fully recursive calculation and simple filter design. Its low design and computational cost are particularly suited to the autonomous signal processing requirements for the Internet of Things. This paper describes how arbitrarily narrow bandpass filters may be designed and implemented using a chain of six Prisms. In one simulation, a design with 40 MHz sampling rate, 1 MHz central frequency and 0.1 Hz bandwidth results in an FIR filter of length 771 million samples. This filter can be evaluated in 0.39 μs per sample on a desktop computer: to achieve this update rate using a conventional non-recursive FIR calculation would require supercomputer resources.