Patent ID: 11061108

Abstract:
In one embodiment, a police activity detector is provided. The detector includes a receiver section and a warning section. The receiver section is configured to receive signals generated in the context of law enforcement activity. The warning section is configured to respond to a pulsed signal received by the receiver section and provide an alert if a received signal correlates to a law enforcement signal. The warning section also includes a sliding window discrete Fourier transform (SWDFT) module configured to receive a plurality of time series of data corresponding to sampling a received pulsed signal at a set of sample rates corresponding to a plurality of target frequencies, perform a SWDFT determination on each of the plurality of time series of data to determine a magnitude of the received signal at each of the targeted frequencies, which reveals the presence of a received pulsed signal when the magnitude is elevated, and issue an alert if the magnitude of the received signal corresponding to at least one of the targeted frequencies is greater than or equal to a predetermined threshold.