The Modeling Of Acoustic Multipath Channel And Research On Equalization Technique

The complex environment of underwater acoustic makes great challenges in underwater communication system. The maximum rate information transmission in band-limited become one of the research focus in current underwater communication.Inter-symbol interference caused by multipath channel effect restricts the high speed communication. Equalization technology is presented in this paper, just about to restrict the inter-symbol interference. The process of underwater acoustic propagation which can be simulated with modeling technology, will supply acoustic channel parameters for Equalization technology which is influenced by the environment of the acoustic channel. Modeling acoustic channel has a large calculated quantity, the development of parallel program technology is inexorable trend to reduce time cost.The research in this paper can be divided into two parts. Based on the ray acoustical multipath channel model and the high performance of the modeling software implementation is the first part of this research, the anti-multipath equilibrium technology will be declared in the second part of this paper.Two important ray acoustical equations are deduced by the simplified wave equation in the first part of this article. The simplified conditions of the model are stated by the two-dimensional propagation model based on the formation interface voice. By using the voice pretreatment, voice screening and iterative approximation eigen voice to achieve efficient search. The modeling software is made in the document-view form,with the use of multithreading technology, the parallel version of the software algorithm become realizable,meanwhile the time efficiency is improved. The channel parameters of the algorithm simulation in second part are provided by this section.The second part of this paper according with whether the train sequence is need or not in the project, the equalization technology is divided into two categories. In the study of equilization technique based on training sequence. firstly, the adaptive equalization technology has been discussed, Analyzing the parameters performance of the equalizer on the two aspects: adaptive algorithms and the structure of equalization. Then, the compressed sensing channel estimation equalization technique based on passive time reversal is deliberated. Using compression perception technology to estimate the channel model with less training sequence, combined with passive technology to realize the anti-multipath effect. In the study of blind equalization technology without training sequence, analyzing the performance of the constant modulus blind equalization algorithm. The fractionally spaced constant modulus algorithm is made further research.