Interference Alignment in 2-user X Channel System with Orthogonal and quasi-orthogonal Space-time Block Codes

직교 및 준직교 시공간 블록 부호를 통한 2-사용자 X 채널에서의 간섭정렬

  • Received : 2015.06.03
  • Accepted : 2015.07.15
  • Published : 2015.08.31


In this paper, we investigate achieving the full diversity order and power gains in case of using OSTBCs and quasi-OSBCs in the x channel system with interference alignment with more than 2 antennas at each terminal. A slight degradation is remarked in the case of quasi-OSTBCs. In terms of receiver structure, we show that due to the favorable structure of the channel matrices, the simple zero-forcing receiver achieves the full diversity order, while the interference cancellation receiver leads to degradations in performance. As compared to the conventional scheme, simulation results demonstrate that our proposed schemes achieve 14dB and 16.5dB of gain at a target bit error rate (BER) of 10-4 in the case of OSTBCs with 3 and 4 antennas at each terminal, respectively, while achieving the same spectral efficiency. Also, a gain of 10dB is achieved at the same target BER in the case of quasi-OSTBC with 4 antennas at each terminal.


Interference alignment;x channel;MIMO detection;orthogonal STBC;quasi-orthogonal STBC


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