空間相関が存在するマルチパスフェージング環境下におけるプロック対角化法に基づくMU-MIMOシステムの伝送特性評価について

摘要

In this paper, transmission performances for MU-MIMO systems based on block diagonalization method in spatially correlated multipath fading environment are analyzed. As compared to the BER performance, instantaneous received C(N+I) and channel capacity of i.i.d channels for each user in computer simulations, it is confirmed that an instantaneous received C(N+I) has about 3dB degradation when spatially correlation is 0.5 and the C(N+I) has about 7dB degradation when it is 0.9. Moreover, the BER performances have about 3dB and 7dB degradations with spatially correlations are 0.5 and 0.9, respectively, and the channel capacity whose average C/N is 20dB. have about 3bit/s/Hz and 8bit/s/Hz degradation with spatially correlations are 0.5 and 0.9,respectively.%本検討では，4×2×2ユーザのマルチユーザMIMOにおいてブロック対角化法を用い2ユーザ分離し，さらにSVD-MIMOに基づく固有モード伝送を想定し，伝搬路に空間相関が存在する場合の特性評価を行った.その結果，各ユーザのパスに対して伝搬路独立(i.i.d)に比べ，相関値0.5において受信C(N+I)値が約3dB劣化し，相関値0.9では約7dBの劣化となることを明らかにした.それに伴い，BER特性がi.i.dと比較し相関値0.5で約3dB,0.9で約7dBの劣化となり，システム全体の伝送容量は平均C/N値20dBにおいてi.i.dの場合に比べて相関値0.5で約3bit/s/Hzの劣化，0.9で約8bit/s/Hzの劣化となることを明らかにした.