Journal of the Institute of Electronics and Information Engineers (전자공학회논문지)

The Institute of Electronics and Information Engineers (대한전자공학회)
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An Efficient Scheme for TDD LTE ICS Exploiting the Reciprocity of the Feedback Channel in TDD LTE Networks

TDD LTE 네트워크에서 궤환 채널의 Reciprocity를 이용한 효율적인 TDD LTE ICS 구조 설계

  • Kim, Hyunchae (School of Electronic Engineering, Soongsil University) ;
  • Im, Sungbin (School of Electronic Engineering, Soongsil University)
  • 김현채 (숭실대학교 정보통신공학과) ;
  • 임성빈 (숭실대학교 전자정보공학부)
  • Received : 2016.01.06
  • Accepted : 2016.01.25
  • Published : 2016.02.25
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Abstract

It is essential to develop an estimation and cancellation algorithm for feedback signals in designing the interference cancellation systems (ICS) as a solution to extending the coverage of the TDD LTE networks. Unlike the radio access of FDD LTE networks, TDD networks utilize the same frequency band in downlink and uplink for radio access. For this reason, downlink and uplink are repeated in time and thus the estimation of the feedback signals in uplink and downlink, respectively, is periodically paused to cause performance degradation. In this study, the reciprocity of downlink and uplink is examined through experiments and exploiting the same frequency band in uplink and downlink, an efficient channel estimation and elimination algorithm is proposed since the algorithm utilizes the same structure for both downlink and uplink.

TDD LTE 네트워크의 커버리지를 확장하는 방법의 하나인 ICS (Interference Cancellation System) 는 궤환 신호의 추정 및 제거 알고리즘 구조에 대한 연구가 필수적이다. FDD 방식의 LTE 네트워크에서의 Radio Access 방식과 달리 TDD 방식에서는 Radio Access를 위해서 하향링크와 상향링크는 동일 주파수 대역을 사용한다. 따라서 하향링크와 상향링크가 시간적으로 반복되며 상하향링크 각각의 궤환 신호의 추정이 주기적으로 정지 상태에 놓이게 되어 성능저하가 발생한다. 본 논문에서는 먼저 하향링크와 상향링크에서 reciprocity를 실험을 통하여 확인하고 하향링크와 상향링크가 동일 주파수 대역을 사용하는 점에 기초하여 채널 추정 및 제거 알고리즘을 하향링크와 상향링크에서 동일하게 사용하는 효과적인 구조를 제안한다.

Keywords

References

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