摘要
在正交频分复用(OFDM)系统中,综合利用时、频域信息的二维差分解调算法(2-DDD),更有利于对抗时频双选信道衰落。该文研究了基于M进制差分幅度相位键控(M-DAPSK)的2-DDD算法,该算法使得基于无编码的64DAPSK-OFDM系统在加性Gauss白噪声信道误码率10-4处可获得1.35 dB的性能增益。为降低2-DDD中最优路径搜索的复杂度,提出了5种可能的解决途径,并分析时间复杂度和空间复杂度。仿真结果表明,采用本文的广度优先存储式算法和深度优先存储式算法,使搜索算法复杂度降低约98%。
A two-dimensional differential demodulation（2-DDD） algorithm can preferably withstand the fading in time and frequency domains,which exploits both the time and frequency dimensions using the orthogonal frequency division multiplexing（OFDM） frame structure.A 2-DDD algorithm was analyzed for M differential amplitude and phase shift keying（M-DAPSK） modulated OFDM signals,which reduced the SNR by about 1.35 dB with a bit error rate of 10-4 in an AWGN channel for an uncoded 64DAPSK-OFDM system.Five reliable solutions were investigated,with the time and space complexity analyzed,to reduce the complexity of the optimal path searching in 2-DDD.Simulations show that the searching algorithm complexity can be reduced by about 98% using the developed algorithm.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第10期1651-1655,共5页
Journal of Tsinghua University(Science and Technology)
基金
清华-高通CDMA无线通信研究计划资助项目(20073000463)
关键词
无线通信
正交频分复用
64进制差分幅度相位键控
二维差分解调
最优路径搜索
wireless communication
orthogonal frequency division multiplexing
64DAPSK
two-dimensional differential demodulation
optimal path searching
