Electronic counter measure system utilizing a digital RF memory

Claim 1

An electronic countermeasure active jamming system comprising: antenna means for receiving and transmitting high frequency electromagnetic signals; a digital radio frequency memory; first control means for enabling said memory to store binary data corresponding to the received signal; second control means for activating said memory to output the stored data for constructing a signal to be applied to the transmitting antenna means; an RF signal data generator which generates one-bit binary logic values for storage in the digital memory, with the data being at a high logic state when the RF signal to be generated is equal to or greater than a predetermined level and at a low logic state when less than said predetermined level, and wherein the generated RF signal data corresponds to an RF signal having constant frequency and phase with respect to time; an RF noise data generator which generates one-bit binary logic values for storage in the digital memory, with the data being at a high logic state when the RF signal to be generated is equal to or greater than a predetermined level and at a low logic state when less than said predetermined level, said values corresponding to an RF noise signal having time varying frequency and phase with respect to time; and a detector for detecting phase coding and chirp modulation of the received signals and for analyzing the frequency spectrum of the received signal memory data to determine if the received signal was frequency modulated.