Design and Implementation of Efficient Symbol Detector for MIMO Spatial Multiplexing Systems

MIMO 공간 다중화 시스템을 위한 효율적인 심볼 검출기의 설계 및 구현

  • 정윤호 (한국항공대학교 항공전자및정보통신공학부)
  • Published : 2008.10.25

Abstract

In this paper, we propose an efficient symbol detection algorithm for multiple-input multiple-output spatial multiplexing (MIMO-SM) systems and present its design and implementation results. By enhancing the performance of the first detected symbol which causes error propagation, the proposed algorithm achieves a considerable performance gain as compared to the conventional sorted QR decomposition (SQRD) based detection and the ordered successive detection (OSD) algorithms. The bit error rate (BER) performance of the proposed detection algorithm is evaluated by the simulation. In case of 16QAM MIMO-SM system with 4 transmit and 4 receive ($4{\times}4$) antennas, at $BER=10^{-3}$ the proposed algorithm obtains the gai improvement of about 2.5-13.5 dB over the conventional algorithms. The proposed detection algorithm was designed in a hardware description language (HDL) and synthesized to gate-level circuits using 0.18um 1.8V CMOS standard cell library. The results show that the proposed algorithm can be implemented without increasing the hardware costs significantly.

본 논문에서는 다중 입출력 (MIMO) 공간다중화 (spatial multiplelxing, SM) 시스템을 위한 효율적인 심볼 검출 알고리즘이 제안되고, 이의 최적 설계 및 구현 결과가 제시된다. 에러 전파 (error propagation)을 야기하는 첫 검출 심볼의 검출 성능을 개선시킴으로써, 제안된 알고리즘은 기존의 정렬된 QR 분해 (sorted QR decomposition, SQRD) 기반 알고리즘이나 정렬된 순차적 검출 (ordered successive detection, OSD) 알고리즘에 비해 성능 이득을 얻을 수 있다. 4개의 송수신 안테나를 갖는 16QAM MIMO-SM 시스템에 대한 성능 평가 결과, 제안된 알고리즘은 기존 알고리즘에 비해 $10^{-3}$의 EBR에서 약 2.5-13.5 dB의 성능 이득을 얻음을 확인하였다. 제안된 알고리즘은 하드웨어 설계 언어를 이용하여 설계 되었고, 0.18um CMOS 표준 셀 공정 라이브러리를 이용하여 합성 및 구현되었다. 구현결과, 제안된 알고리즘은 하드웨어의 큰 증가없이 구현 가능함을 확인할 수 있었다.

Keywords

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