A Rejection Method for Interference Waves Caused by Sporadic-E Ionospheric Propagation
In Japan, VHF low channel television services are sometimes disturbed by interference from distant foreign FM transmitters. It is caused by signal which propagate via the sporadic-E layer of the ionosphere. A method is proposed for eliminating narrow band FM interference waves in television signal. The method uses quadrature synchronous detection of the television signal and Hilbert transformation. The analysis was obtained, and an experimental system was made. The system reduced interference wave for 40 dB.
KeywordsPhase Error Television Signal Notch Filter Quadrature Component Amplitude Error
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