Hardware Implementation of an SK Spectrometer

A wideband spectrometer of 500 MHz instantaneous bandwidth is described that includes an implementation of the Spectral Kurtosis (SK) algorithm for automatic radio frequency interference (RFI) detection. An SK spectrometer accumulates both power and power-squared, which are then used to develop the SK estimator. The SK spectrometer of the Korean Solar Radio Burst Locator (KSRBL) has a 2 GHz instantaneous bandwidth that is time multiplexed over the 0.24-18 GHz radio frequency range, for the study of solar bursts. We use a novel presentation of the data from the spectrometers to classify types of RFI. It is found that the algorithm is especially useful for excising highly intermittent RFI but is less successful for RFI due to digital signals. The method of multiscale SK is presented that addresses the known blindness of Kurtosis-based estimators to 50% duty-cycle RFI.