A Novel Digital Filter Algorithm for High-resolution Spectrum Detection Based on Chirp Transform Spectrometer

Abstract

In this paper, we present a novel digital filter algorithm for high-resolution spectrum detection based on chirp transform spectrometer (CTS). Instead of using a surface acoustic wave (SAW) filter as a compressor, we build a digital filter algorithm for matched filtering. By specially selecting and processing the discrete sampling points of the output chirp modulated signals, a chirp signal with known chirp rate, start frequency and bandwidth can be compressed as a pulse in time domain. The entire spectrum can be obtained though shifting the sampling points vector in time domain. This method realizes high-resolution spectrum measurement though digital pulse compression. Compared to the traditional digital convolution pulse compression method, the new digital filter algorithm saves a lot of computation.