Communication systems

Claim 2

A receiver for a radio communications system in which first and second signals relating to message information are sequentially transmitted at different frequencies to said receiver, said receiver receiving and detecting said first and second signals in sequence and further including an interference assessment circuit for monitoring during reception and detection of said first signal at least one frequency band including said second signal and to estimate the levels of any interfering signals in said at least one band and an adaptive filter connected to said interference assessment circuit whereby said circuit controls the response of said filter, and wherein said adaptive filter receives said first and second signals in sequence and to attenuates interfering signals in a frequency band including the first signal in accordance with the interference signal levels estimated by said interference assessment circuit.

Claim 3

A receiver as in claim 1 wherein said interference assessment circuit includes a plurality `p` of bandpass filters connected in parallel to receive said second signals, a plurality `p` of averaging circuits, each of said averaging circuits connected to an associated one of said bandpass filters to rectify and average a voltage output therefrom, and means for applying the averaged voltage outputs from the averaging circuits to control the response of said adaptive filter.

Claim 4

A receiver as in claim 2 wherein said adaptive filter includes a plurality `p` of bandpass filters, and a plurality `p` of amplifiers each connected to receive the output of an associated one of said bandpass filters, wherein the gain of each of said amplifiers is controlled by an associated one of said averaged voltage outputs.

Claim 5

A receiver for a radio communications system in which signals related to message information are transmitted to said receiver and detected thereby, said signals exhibiting a frequency which successively varies in a predetermined frequency order from one predetermined frequency to a next predetermined frequency, said receiver comprising: interference assessment means for monitoring at least one frequency band including at least said next predetermined frequency during reception and detection of said one predetermined frequency, and for generating estimation signals corresponding to any interfering signals monitored within said monitored frequency band; and, adaptive filter means coupled to said interference assessment circuit and having a filter response controlled by said estimation signals for attenuating the interfering signals in a frequency band including the one predetermined frequency in accordance with said estimation signals.

Claim 6

A receiver for a radio communications system in which signals related to message information are transmitted to said receiver and detected thereby, said signals exhibiting a frequency which successively varies in a predetermined frequency order from one predetermined frequency to a next predetermined frequency, said receiver comprising: interference assessment means for monitoring at least one frequency band including at least said next predetermined frequency during reception and detection of said one predetermined frequency, and for generating estimation signals corresponding to any interfering signals monitored within said monitored frequency band; and, adaptive filter means coupled to said interference assessment circuit and having a filter response controlled by said estimation signals for attenuating the interfering signals in a frequency band including the one predetermined frequency in accordance with said estimation signals.