基于统计特性的MIMO水声信道容量分析

发布时间：2018-10-31 13:31

【摘要】：随着海洋资源的大规模开发利用以及海洋军事战略方针的迫切需要,利用水下声信道进行信息传输的需求大大增加。水声信道容量作为一个非常重要的衡量水声信道状况的因素,具有很大的研究意义和价值。限制氋速水下声通信的主要因素就是极为有限的带宽,因为MIMO(Multiple Input Multiple Output)技术能提高无线通信系统的频带利用率,故MIMO技术在水声通信中的应用前景很大。目前,计算水声信道容量主要包括实地测量和计算机仿真建模两种方法。其中水声信道建模大致分为静态的水声传播模型和动态的随机统计的水声信道模型。然而,目前对动态水声信道容量模型的研究并不多。本文建立的水声信道容量仿真模型是一种基于信道统计特性的MIMO信道模型。它是一种满足随机性和时变性的动态模型,更接近于复杂的海洋状况。这种信道模型更准确是由于它考虑到了水声传播的物理规律,比如传输损耗、底部表面反射、多径效应和多普勒频移,以及不可避免的随机局部位移的影响。本文先搭建了一个SISO(Single Input Single Output)的信道模型,并对其信道容量进行综合分析。然后把模型扩展到MIMO信道,并在Matlab平台上做了大量的仿真实验。最后,将MIMO与SISO的信道容量进行比较,得到结论:MIMO信道可以明显提高水声信道容量。而且还分析研究了信号频率、信噪比、传输带宽、传输距离和水深等因素对水声信道容量的影响。这种时变的MIMO水声信道的容量仿真模型,克服了水声信道地点不确定性和环境条件变化的缺点,还有效地提高了水声信道的信道容量。这种信道满足随机性,更接近实际情况,而且便于实时监测。仿真分析获得的一些结论在信道性能仿真研究、水声传输系统的设计、实际测量等方面都有重要的指导意义。
[Abstract]:With the large-scale exploitation and utilization of marine resources and the urgent need of marine military strategy, the need of underwater acoustic channel for information transmission is greatly increased. As a very important factor to measure the underwater acoustic channel capacity, underwater acoustic channel capacity has great significance and value. The main factor limiting underwater acoustic communication is the very limited bandwidth, because MIMO (Multiple Input Multiple Output) technology can improve the frequency band efficiency of wireless communication system, so the application prospect of MIMO technology in underwater acoustic communication is very large. At present, the calculation of underwater acoustic channel capacity mainly includes two methods: field measurement and computer simulation modeling. Underwater acoustic channel modeling is divided into static underwater acoustic propagation model and dynamic stochastic statistical underwater acoustic channel model. However, there are few researches on dynamic underwater acoustic channel capacity model. The underwater acoustic channel capacity simulation model established in this paper is a MIMO channel model based on channel statistics. It is a stochastic and time-varying dynamic model, which is closer to the complex ocean conditions. This channel model is more accurate because it takes into account the physical laws of underwater acoustic propagation, such as transmission loss, bottom surface reflection, multipath effect and Doppler frequency shift, as well as the inevitable random local displacement. In this paper, a channel model of SISO (Single Input Single Output) is built, and its channel capacity is analyzed synthetically. Then the model is extended to MIMO channel, and a lot of simulation experiments are done on Matlab platform. Finally, the channel capacity of MIMO and SISO is compared, and the conclusion is drawn that the MIMO channel can obviously improve the underwater acoustic channel capacity. The effects of signal frequency, signal-to-noise ratio (SNR), transmission bandwidth, transmission distance and depth on the underwater acoustic channel capacity are also analyzed. The time-varying MIMO underwater acoustic channel capacity simulation model not only overcomes the shortcomings of the underwater acoustic channel location uncertainty and environmental conditions, but also effectively improves the channel capacity of underwater acoustic channel. This channel satisfies randomness, is closer to the actual situation, and is easy to monitor in real time. Some conclusions obtained from simulation analysis have important guiding significance in channel performance simulation research, design of underwater acoustic transmission system and actual measurement.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN929.3

【相似文献】