Interference cancelling system and method

Claim 1

An interference cancelling system for cancelling or minimizing multiple signal components of a received signal in a radio receiver caused by an interfering signal from a radio transmitter, which interfering signal follows multiple paths to the radio receiver, which comprises: sampling means for sampling the interfering signal transmitted from the radio transmitter, the sampling means having an output and providing on the output a primary sample signal corresponding to the interfering signal sampled; means for providing a primary sample signal path from the radio transmitter to the radio receiver; dividing means for dividing at least a portion of the primary sample signal path into a plurality of secondary sample signal paths, the number of secondary sample signal paths corresponding to at least the number of multiple paths which the interfering signal follows to the radio receiver, the primary sample signal being divided into a plurality of secondary sample signals, each secondary sample signal following a corresponding secondary sample signal path; at least one of the secondary sample signal paths being provided with delay adjusting means for adjusting the time delay of the secondary sample signal of said at least one path having said delay adjusting means; at least one of the secondary sample signal paths being provided with amplitude adjusting means for adjusting the amplitude of the secondary sample signal of said at least one path having said amplitude adjusting means; each of the secondary sample signals corresponding to one of the multiple components of the received signal caused by the multipath interfering signal; combining means for combining the plurality of secondary sample signal paths into said primary sample signal path, the combining means including an output and providing on the output an adjusted primary sample signal having signal components corresponding to the secondary sample signals; the delay adjusting means and amplitude adjusting means of the secondary sample signal paths being adjusted such that the signal components of the adjusted primary sample signal substantially equal in amplitude and time delay the corresponding multiple signal components of the received signal caused by the interfering signal; and subtracting means coupled to the primary sample signal path for subtracting the adjusted primary sample signal from the received signal, whereby the signal components of the adjusted primary sample signal cancel or minimize the corresponding multiple signal components of the received signal caused by the interfering signal.

Claim 12

A method of cancelling or minimizing multiple signal components of a received signal in a radio receiver caused by an interfering signal from a radio transmitter, which interfering signal follows multiple paths to the radio receiver, which comprises the steps of: sampling the interfering signal transmitted from the radio transmitter, and providing a primary sample signal corresponding to the interfering signal sampled; providing a primary sample signal path from the radio transmitter to the radio receiver; dividing at least a portion of the primary sample signal path into a plurality of secondary sample signal paths, the number of secondary sample signal paths corresponding to at least the number of multiple paths which the interfering signal follows to the radio receiver, the primary sample signal being divided into a plurality of secondary sample signals, each secondary sample signal following a corresponding secondary sample signal path; adjusting the time delay of at least one of the secondary sample signals; adjusting the amplitude of at least one of the secondary sample signals; each of the secondary sample signals corresponding to one of the multiple components of the received signal caused by the multipath interfering signal; combining the plurality of secondary sample signal paths into said primary sample signal path, and providing an adjusted primary sample signal having signal components corresponding to the secondary sample signals; the time delay and the amplitude of the secondary sample signals being adjusted such that the signal components of the adjusted primary sample signal substantially equal in amplitude and time delay the corresponding multiple signal components of the received signal caused by the interfering signal; and subtracting the adjusted primary sample signal from the received signal so as to cause the signal components of the adjusted primary sample signal to cancel or minimize the corresponding multiple signal components of the received signal caused by the interfering signal.

Claim 13

A method of cancelling or minimizing multiple signal components of a received signal in a radio receiver caused by an interfering signal from a radio transmitter, which interfering signal follows multiple paths to the radio receiver, which comprises the steps of: sampling the interfering signal transmitted from the radio transmitter, and providing a primary sample signal corresponding to the interfering signal sampled; providing a primary sample signal path from the radio transmitter to the radio receiver; dividing at least a portion of the primary sample signal path into a plurality of secondary sample signal paths, the number of secondary sample signal paths corresponding to at least the number of multiple paths which the interfering signal follows to the radio receiver, the primary sample signal being divided into a plurality of secondary sample signals, each secondary sample signal following a corresponding secondary sample signal path; adjusting the time delay of at least one of the secondary sample signals; adjusting the amplitude of at least one of the secondary sample signals; each of the secondary sample signals corresponding to one of the multiple components of the received signal caused by the multipath interfering signal; combining the plurality of secondary sample signal paths into said primary sample signal path, and providing an adjusted primary sample signal having signal components corresponding to the secondary sample signals; the time delay and the amplitude of the secondary sample signals being adjusted such that the signal components of the adjusted primary sample signal substantially equal in amplitude and time delay the corresponding multiple signal components of the received signal caused by the interfering signal; and subtracting the adjusted primary sample signal from the received signal so as to cause the signal components of the adjusted primary sample signal to cancel or minimize the corresponding multiple signal components of the received signal caused by the interfering signal.