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A Rejection Method for Interference Waves Caused by Sporadic-E Ionospheric Propagation

  • H. Arata
  • S. Yamazaki

Abstract

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.

Keywords

Phase Error Television Signal Notch Filter Quadrature Component Amplitude Error 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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    Edwards K.J. and L. F. Shrubsole (1984) Sporadic-E Propagation at Frequencies around 70 MHz, The Radio and Electronic Engineer, Vol.54, No.5, pp.231–237, MayCrossRefGoogle Scholar
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    J.L. Eaton and H.M.Price (1980) Co-channel interference reduction in television rebroadcast links by means of video notch filters, E.B.U. Review technical part, pp.20–23, No.179, February.Google Scholar
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    S.Yamazaki and H.Arata (1984) Rejection of sporadic-E interference in TV reception using notch filters, IEEE EMC Symposium, Tokyo, Japan, pp.2–806, October.Google Scholar
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    M.Schwartz (1990) Information transmission, modulation and noise, fourth edition, McGraw-Hill,chapter 4–7Google Scholar
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    CCIR (1982) Ratio of wanted-to unwanted signal for AM vestigial sideband colour television system, Question 4/11, Study Programme 4A/11, report 306–4, p. 232Google Scholar

Copyright information

© Springer-Verlag Tokyo 1991

Authors and Affiliations

  • H. Arata
    • 1
  • S. Yamazaki
    • 1
  1. 1.Radio Engineering DivisionNHK (Japan Broadcasting Corporation) Science and Technical Research LaboratoriesTokyoJapan

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