摘要 |
Substantially complete cancellation of continuous wave or slowly varying continuous wave interference with no loss in the received level of the desired signals is provided for a spread spectrum system which utilizes orthogonal multiplexed noise codes which when orthogonally multiplexed, detected in a matched filter detector and linearly added, compress to a lobeless impulse. The noise codes are comprised of binary digital noise codes which compress to a code bit width tau . The CW interference is eliminated by means of a variable delay line and a linear adder. The delay line operates to provide an interference signal from the input interference signal which is exactly 180 DEG out of phase with respect to the input interference signal. By adding the delayed signal to the input signal in the linear adder, a total cancellation of the interference signal occurs while the signal level of the noise coded communications signal remains unchanged.
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