Abstract: In accordance with one form of the present invention, an Adaptively Peaked Super-Regenerative Filter (APSRF) is provided, which preferably includes an interference suppression system (ISS), a summing block, a phase splitter, one or more variable attenuators, three couplers, an amplifier and a filter. The APSRF provides for significant narrowing of the bandwidth and a significant increase in the SNR and Q transfer function of the filter. The output of the amplifier or filter is sampled by one of the couplers and used as a reference sample signal to the ISS. The ISS includes an adaptive loop, which adjusts the reference sample signal in phase and amplitude to form a replica signal. The replica signal is designed to cancel an input sample signal taken from another coupler and applied to the summing block. An output of the summing block provides an error sample signal to the ISS, which enables the ISS to adaptively optimize the nulling function by adjusting the amplitude and phase of the replica signal.

Abstract: Adaptive apparatus for eliminating interference from a received signal provided on a transmission line caused by radio transceivers includes a plurality of frequency tunable filters tuned to the operating frequency of a corresponding transmitter. The transmitter signal of each transmitter is provided to a corresponding filter. The filter eliminates the non-essential transmission of harmonics, intermodulation and wideband noise of the transmission signal. The adaptive apparatus includes a plurality of cancellation devices wherein each cancellation device receives a sample of each filtered transmission signal and the received signal. The received signal includes an error portion generated by the transmitters and a non-error portion corresponding to the signal received by the antenna. Each cancellation device compares the corresponding sampled transmission signal with the sample of the received signal.

Abstract: A method is provided for obtaining a reference signal for suppressing an interfering signal received by a radio receiver system. The radio receiver system receives the interfering signal on an antenna along with a signal of interest. An electrically conducting structure on which is present an interfering signal corresponding to the interfering signal present on the antenna and close to the antenna is selected and the interfering signal present on the conducting surface is sampled to obtain a reference signal. The reference signal is provided to an interference cancellation system which generates a cancellation signal used to suppress the interfering signal received by the radio receiver system.

Abstract: A radio system and interference cancellation system for use with the radio system include a receiving radio and a transmitting radio which are coupled to a common antenna. A reference coupler provides a reference signal in response to the signal transmitted by the transmitting radio and provides the reference signal to a vector modulator and a synchronous detector. A receiver coupler is responsive to the transmitted signal which is reflected by the antenna and to the signal which is desired to be received and provides a received signal containing an interfering signal component and a desired signal component. An error coupler samples the received signal which includes any residual interfering signal component after cancellation, and provides an error signal to the synchronous detector. The synchronous detector compares the reference signal with the error signal and provides a detector output to the vector modulator.