OFDM adaptive antenna array with frequency-domain weight updating and delay time-domain channel estimation
نویسندگان
چکیده
あらまし 適応アンテナアレーはマルチアクセス干渉を抑圧できるので,移動通信における上りリンク容量を向上できる技 術として期待されている.OFDM 適応アンテナアレーは Pre-FFT 型と Post-FFT 型に分類される.Pre-FFT 型は受信サンプリ ング毎に更新可能であるため,アレー重みの高速収束が可能であることが知られている.一方筆者らは,Post-FFT 型におい ても,各サブキャリアにおいて同一のアレー重みを用いる周波数領域更新 OFDM 適応アンテナアレーであれば,1OFDM シ ンボル当たりサブキャリア数回の更新が可能となるため,高速収束が可能であることを理想チャネル推定時において示してき た.しかしながら提案方式には参照信号生成にチャネル情報が必要であり,チャネル推定精度が BER 特性に大きな影響を 与えると考えられる.本論文では遅延時間領域チャネル推定を用い,チャネル推定を行った場合にも周波数領域重み更新 適応アンテナアレーがアレー重みの高速収束を達成できること,さらに高速フェージングに追従する優れた特性を有すること 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 OFDM,適応アンテナアレー,適応アルゴリズム
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تاریخ انتشار 2006