By studying the discrete fourier transform properties of the band - limited digital signal , the authors introduce alternating projection neural networks into the paper , expand apnn ' s application scope from real field to complex field , and present several important conclusions on apnn . analyzing and discussing network ' s tolerance to noise , convergence rate and the spectral leakage problem of the truncated signal expected to be extrapolated by using these conclusions , the paper presents an extrapolation algorithm for band - limited signals based on alternating projection neural networks . a lot of simulation experiments show that the algorithm is effective . in addition , the algorithm is also effective to spectrum extrapolation . owing to adopting network structure , the algorithm is prone to parallel computation and vlsi design , and consequently can satisfy real time military processing needs 本文通過對(duì)頻帶受限數(shù)字信號(hào)的離散傅立葉變換特性的研究,引進(jìn)了交替投影神經(jīng)網(wǎng)絡(luò),并將其應(yīng)用范圍從實(shí)數(shù)域拓廣到復(fù)數(shù)域,且給出了在復(fù)數(shù)域仍然成立的若干結(jié)論.運(yùn)用這些結(jié)論,在對(duì)網(wǎng)絡(luò)噪聲抑制、網(wǎng)絡(luò)收斂速度及待外推信號(hào)因截?cái)喽斐深l譜嚴(yán)重外泄問題的分析與討論的基礎(chǔ)上,提出了一種基于交替投影神經(jīng)網(wǎng)絡(luò)的外推算法.仿真實(shí)驗(yàn)表明該方法是行之有效的.另外,該算法對(duì)頻譜外推同樣適用;由于它采用全互連神經(jīng)網(wǎng)絡(luò)結(jié)構(gòu),易于并行計(jì)算和vlsi實(shí)現(xiàn),從而可滿足軍事上實(shí)時(shí)處理的需要