Throughput Performance of DS-CDMA HARQ With Overlap FDE Using Pilot-assisted Channel Estimation
نویسندگان
چکیده
あらまし 次世代移動無線通信では超高速パケットアクセスが主流になり,誤り訂正符号化と自動再送要求 (ARQ)を組み合わせたハイブリッド ARQ(HARQ)が重要な技術になると考えられる.直接拡散符号分割マルチアク セス(DS-CDMA)を対象に,平均 2 乗誤差最小(MMSE)規範に基づく周波数領域等化(FDE)を用いることで,よく知ら れた Rake 合成受信よりも優れた伝送特性が得られることが示されている.FDE を用いる場合にはブロック間干渉 (IBI)を避けるためにガードインターバル(GI)の挿入が必要であるが,これは伝送効率の低下を招く.そこで最近, GI の挿入を必要としないオーバーラップ FDE が提案された.筆者らは以前,オーバーラップ FDE を用いる DS-CDMA HARQ のスループット特性を明らかにしたが,これまでの検討では理想チャネル推定を仮定していた. 本報告では,オーバーラップ FDE を用いる DS-CDMA HARQ のパイロットチャネル推定時のスループット特性を 計算機シミュレーションにより明らかにしている. キーワード DS-CDMA,オーバーラップ FDE,HARQ,パイロットチャネル推定
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