Variable time delay control structure for channel matching

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).