Collision Dispersion Based on Orthogonal Pre-Spreading in Orthogonal Code Hopping Multiplexing

OCHM 시스템에서 전확산에 의한 충돌 분산 기법

  • Published : 2009.09.30

Abstract

A collision dispersion scheme based on orthogonal pre-spreading is proposed to reduce the effect of collisions that occur in orthogonal code hopping multiplexing(OCHM). The OCHM scheme was previously proposed to accommodate a significantly larger number of low-activity bursty channels than the number of orthogonal codewords. The proposed scheme greatly reduces the required SNR in channel decoding. In addition, the proposed scheme can be applied to OFHM based on OFDM.

OCHM(orthogonal code hoppging multiplexing) 방식은 시스템의 직교 부호 채널 수보다 훨씬 많은 숫자의 저 활성도 채널을 수용하기 위해 고안되었다. 본 논문에서는 OCHM 시스템에서 발생하는 심볼 충돌에 의한 열화를 줄이기 위해 직교 전확산(pre-spreading)에 기반한 충돌 분산 기법을 제안한다. 제안된 방식은 채널 복호 과정에서 요구 신호대 잡음비를 대폭 개선한다. 또한 본 방식은 OFDM에 기반한 주파수 도약인 OFHM 시스템에도 적용될 수 있다.

Keywords

References

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