Combing the method of subspace with output energy minimum criterion , we give the estimated values of the channel parameters and timing of the desired user , and many computer simulations show the efficiency of the proposed methods in the case of different snr and different sir 提出了多子波cdma多址框架并研究了其抗噪性能。目前所使用的直接序列擴(kuò)頻cdma系統(tǒng),具有軟容量和抗干擾等諸多優(yōu)點(diǎn)。多址干擾、多徑干擾、遠(yuǎn)近效應(yīng)和環(huán)境噪聲是這種系統(tǒng)的主要問題。