Analog Chirp Fourier Transform for high-resolution real-time wideband RF spectrum Analysis

Application of the Analog Chirp Fourier Transform (ACFT) in generating low-latency, continuous, real-time frequency spectra of wide bandwidth radio frequeny (RF) signals is presented as an alternative to the digital FFT processor. Insights into the mathematical construct of ACFT, system modeling, and practical design considerations are presented. Resolution and worst-case frequency error are key metrics evaluated over design parameter choices and process, voltage, and temperature (PVT)-induced parameter variations. Experiments show accurate frequency spectrum representation over several decades extending from 200 MHz to 6 GHz with a 58 MHz worst-case resolution and 1 μs latency.