Patent ID: 8411809

Claim:
An interference cancellation system, comprising: (A) a variable delay line ( 19 ) for adjusting a signal propagation time of a sampled transmission signal ( 40 ) propagated through a controlled propagation path, the variable delay line ( 19 ) comprising a delay having an adjustment range to compensate for delay differences in the sampled signal path and an uncontrolled propagation path, the delay comprising: at least one fixed delay element; and a variable delay element continuously varying a delay of sampled transmission signal to implement a match between the sampled transmission signal and a propagated received signal propagated through the uncontrolled propagation path yielding a delayed coupled signal; (B) an adaptive time delay control (ATDC) module ( 10 ) for receiving the sampled transmission signal and the propagated received signal, delaying the sampled transmission signal and the propagated received signal, generating a first autocorrelation value from the sampled transmission signal and the delayed propagated received signal, generating a second autocorrelation value from the delayed sampled transmission signal and the delayed propagated received signal, and continuously calculating a delay based on the first and second autocorrelation values to be added to the controlled propagation path through the variable delay element to achieve a match of the sampled transmission signal passing through the controlled propagation path with the propagated received signal passing through the uncontrolled propagation path; and (C) an adaptive control loop ( 6 ) for adjusting a complex weighting of the delayed coupled signal ( 57 ) to maximally cancel the sampled transmission signal received in the propagated received signal ( 30 ).