# 이중 선택적 채널 OFDM 시스템을 위한 블록 선형 MMSE 등화 방식의 성능 분석

• Lim, Dong-Min (Department of Electronic Engineering, Gyeongsang National University)
• 임동민 (경상대학교 전자공학과)
• Published : 2010.01.31
• 62 6

#### Abstract

In this paper, we analyze the performance of the block linear MMSE equalization for OFDM systems in doubly selective channels by computer simulations. The block linear MMSE equalization shows somewhat unusual BER characteristics in that the BER curve drops at first as SNR increases but then rises up as SNR increases further beyond some point. In this paper, we investigate the BER characteristics of the block linear MMSE equalization by analyzing the condition number of the coefficient matrix in the linear system involved in the equalization process, and propose a new method to avoid the BER performance degradation at high SNR.

#### Keywords

OFDM;Doubly Selective Channel;Linear MMSE Equalization;Condition Number

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