Simulating Spectral Kurtosis Mitigation against Realistic Radio Frequency Interference Signals

Abstract

We investigate the effectiveness of the statistical radio frequency interference (RFI) mitigation technique spectral kurtosis () in the face of simulated realistic RFI signals. estimates the kurtosis of a collection of M power values in a single channel and provides a detection metric that is able to discern between human-made RFI and incoherent astronomical signals of interest. We test the ability of to flag signals with various representative modulation types, data rates, duty cycles, and carrier frequencies. We flag with various accumulation lengths M and implement multiscale , which combines information from adjacent time-frequency bins to mitigate weaknesses in single-scale . We find that signals with significant sidelobe emission from high data rates are harder to flag, as well as signals with a 50% effective duty cycle and weak signal-to-noise ratios. Multiscale with at least one extra channel can detect both the center channel and sideband interference, flagging greater than 90% as long as the bin channel width is wider in frequency than the RFI.