Effect of Channel Estimation Error for OFDM/TDM
نویسندگان
چکیده
あらまし 直交周波数分割多重(OFDM: Orthogonal frequency division multiplexing)と時分割多重(TDM: Time division multiplexing)とを組み合わせた OFDM/TDMは,周波数領域等化(FDE: Frequency-domain equalization)を用いること で OFDMとシングルキャリア(SC: Single carrier)伝送を橋渡しできる伝送方式である.FDEのためには高精度なチャ ネル推定が必要である.周期的に送信された既知パイロットを用いるチャネル推定が知られている.チャネル推定 に誤差があると OFDM/TDMでは符号間干渉(ISI: Inter-symbol interference)が発生してしまう.本論文では推定し たチャネルインパルス応答にガウス分布する誤差が存在するとするガウス誤差モデルを用い,チャネル推定誤差が OFDM/TDM の平均ビット誤り率(BER)特性に与える影響を理論検討している.モンテカルロ数値計算により, OFDM/TDMが SCに近づくにつれチャネル推定誤差の影響を受けやすくなり,平均 BERが大きく劣化することを 示している. キーワード OFDM/TDM, チャネル推定誤差,周波数領域等化
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تاریخ انتشار 2005