Journal of the Korean Society for Aeronautical & Space Sciences (한국항공우주학회지)

The Korean Society for Aeronautical and Space Sciences (한국항공우주학회)
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PCM/FM With Modulation Index of 2/3

변조지수가 2/3인 PCM/FM

  • Received : 2021.07.29
  • Accepted : 2021.10.08
  • Published : 2021.11.01
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Abstract

PCM/FM with a modulation index of 0.7 is widely used in the telemetry field. If the modulation index is slightly changed to 2/3, it can be interpreted as 3-PSK with a state number of 3 in phase transition trellis and can be received with a simple Viterbi decoder. As a result of computer simulation, the Eb/No performance in the AWGN channel is about 8.3 dB when the BER is 10-5, which is close to the theoretical limit.

텔레메트리 분야에서 많이 사용되는 PCM/FM은 변조지수가 0.7인데 이를 2/3로 변경하면 3-PSK로 해석이 가능하며 위상 변화 트렐리스 상태수가 3이 되어 간단한 비터비 복호기로 수신이 가능하다. 컴퓨터 모의실험한 결과 AWGN 채널에서 Eb/No 수신 성능은 BER이 10-5일 때 약 8.3dB로 이론적 한계값에 근접한다.

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References

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