Method and apparatus for shipboard co-site in-band desired signal extraction

A method of removing interference signals without the use of band pass filtering, in a time-harmonic composite signal processed by a receiver that is stationary with respect to at least one co-site transmitter, comprising:

• momentarily inhibiting transmission of the desired signal;
• sampling an in-band interfering signal from the at least one co-site stationary transmitters by the co-site stationary receiver;
• storing the value of the in-band interfering signal;
• transmitting the desired signal from the desired transmitter;
• sampling the time-harmonic composite signal having the in-band interfering signal and the in-band desired signal by the co-site stationary receiver;
• deriving a phase difference from the composite signal and the sampled in-band interfering signal based on a relationship between the two signals defined as the phase difference between the composite signal and the sampled in-band signal is approximately equal to the difference of a Fourier-transform phase value of each signal;
• applying the derived phase difference value to the sampled in-band interfering signal to estimate a synchronized current in-band interfering signal by utilizing a time latency value determined by dividing the derived phase difference value by a sum of two times pi (π), wherein π is equal to 3.14;
• and
• generating an un-interfered, in-band desired signal by subtracting the synchronized current in-band interfering signal value from a current composite signal.