消除冗余循环前缀的水声信道OFDM频域均衡算法  

Frequency-domain equalization algorithm to eliminate redundant circular prefix for OFDM underwater acoustic communications

作　　者：冯成旭[1] 许江湖[1] 罗亚松[1] 

机构地区：[1]海军工程大学电子工程学院,湖北武汉430033

出　　处：《哈尔滨工程大学学报》2014年第4期482-487,共6页Journal of Harbin Engineering University

基　　金：国家自然科学基金资助项目(61101205)

摘　　要：针对OFDM传统频域均衡算法依赖较长冗余循环前缀,造成水声信道利用率下降的问题,依据OFDM的调制解调原理,在对水声信道多径效应造成影响进行数学建模的基础上,引入多级缓冲机制和判决反馈机制,提出了新型的判决反馈OFDM频域均衡算法。对算法计算量进行了简化,并给出均衡器阶数自适应选择方案。通过仿真和水池实验,证明新算法可以在完全没有循环前缀参与情况下,实现对多径效应的有效补偿,保证了有限水声信道带宽条件下的高速、低误码率的可靠通信。The traditional OFDM frequency-domain equalization algorithm depends on the long circular prefix which decreases the utilization rate of the underwater acoustic channel. Based on the theory of modulation and demodula-tion of OFDM, a mathematical model based on the influences of multipath effects in the underwater acoustic chan-nel was established. On the basis of this, a multi-level buffering mechanism and decision feedback mechanism were introduced and a new OFDM frequency-domain equalization algorithm was proposed. The computing volume of the new algorithm was simplified and an equalizer order self-adaptive selection scheme was given. The results of the simulations and pool experiment prove that the new algorithm may effectively achieve the compensation for multipath effects in the case of a complete lack of the participation of a redundant circular prefix, which ensures reliable com-munication with high speed and low bit error rates under the condition of a limited bandwidth underwater acoustic channel.

关 键 词：水声通信 频域均衡算法 循环前缀 多径效应 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]