Research On The Major Technic Of The Self-adaptive Interference Cancellation System Operating On V/UHF

With the rapidly developing of wireless transmission, the requirements for signal quality in wireless transmission are more and more stricter. It is essential to eliminate all kinds of interferences in transmission channel to improve Signal-to-Noise Ratio (SNR). There are man-made noise, natural noise and internal noise according to its origin, and man-made noise is the most complex and various. Noise abatement is one of methods to to improve the SNR. Great improvement of the SNR can be made if we can restrain the man-made noise effectively.This paper describes an interference cancellation system which operates on V/UHF. The interference canceller can improve SNR via eliminating man-made noise in wireless channel. The interference cancellation system can improve rejection of interference signal with the site coupled from a transmission antenna into a local receive antenna in the presence of local multi-path. The interference has an instantaneously limited bandwidth communication channel operating over V/UHF. The interference cancellation system is designed based on characteristic of interferences and principium of self-adaptive Orthogonal vector synthesis.This paper mainly focuses on parts of interference cancellation system modules, such as electrically controlled attenuator, broadband correlator, broadband power combiner and controller, then analyzes the theory of modules, proposes applicable solutions based on the theory and designed the corresponding hardware implementations, at last makes same performance tests and discuss the results. There are also advantages and disadvantages, so the approach in this paper serves as a foundation for the work in the future.