无速率编码与矢量多载波调制在高移动无线通信中的应用

发布时间：2018-06-14 13:04

本文选题：无线通信 + 高移动　；参考：《浙江大学》2017年硕士论文

【摘要】：随着无线通信、网络技术的发展以及社会需求的不断提高,在高移动场景中提供可靠、高质量的无线通信服务已经成为通信领域的研究热点。高移动无线宽带通信中的无线信道在时间以及频率维度对信号产生影响,因此高移动信道具有双选择性。高移动无线通信场景已经深入我们生活中的方方面面,亟需研究实际可行的方案与系统,在实际场景中减轻高移动信道的影响,提高通信传输效率,并基于实践,为理论研究提供新的方向。本文主要围绕高移动无线通信场景下无速率编码以及矢量多载波调制技术的应用,内容分为:本文提出了一种基于矢量多载波调制的低复杂度高移动双选择衰落信道估计方法。首先分析了矢量多载波调制在CE-BEM建模的双选择信道中的符号扩展的具体数学形式。基于符号扩展结构,设计了在发送端的矢量多载波调制数据符号块中插入导频的方式以及在接收端基于该导频估计双选择信道CE-BEM参数的方法。该方法相比传统基于OFDM的信道估计方法,在移动性越高的情况下,越能够降低导频开销,具有更低的计算复杂度。也提出了一种矢量多载波调制系统中对传统CE-BEM建模的改进方案,通过引入混淆,牺牲了信道估计的准确度,使得信道估计值在信道均衡阶段有更好的性能。本文提出了高移动场景下无速率码矢量多载波通信系统设计方案。通过分析无速率码以及矢量多载波调制方案的特点,提出了将它们组成联合编码调制系统。设计了数据拆分成帧方案、传输机制、物理层帧的生成及接受处理流程以及多级流水线译码机制。为了验证系统设计的可行性,我们使用软件无线电平台SORA编程实现了上述系统,产出了系统原型。在实际验证中,系统能够快速跟踪信道的变化,并通过无速率码的桶积水特性适应不同移动性下的信道容量,在高效率译码机制的帮助下,在移动性不断变化的时能自适应地获得近似最优的整体吞吐率。本文最后基于无速率码,设计了自适应多分辨率数据广播系统。基于不等差错保护的概念,我们设计了实际的多分辨率无速率码,使得发送端基本不需要了解接收端信息或者接受反馈,独立地发送一个数据流。在接收端,这样的无速率码保证了越重要的数据的信息量累计的越多,参与的译码迭代次数也越多。此后,又根据广播系统中的保证最低质量场景以及尽力传输场景,设计了相关广播系统的实现方案。通过统一考虑接收端的计算、通信能力,实现了广播场景中接收端数据量的自适应,使得所有接收端能够从一个单一的发送源中获取其计算、通信能力限制下的近似最高数据质量,并降低了发送端的开销。
[Abstract]:With the development of wireless communication, the development of network technology and the continuous improvement of social demand, providing reliable and high-quality wireless communication services in high mobile scenes has become a research hotspot in the field of communication. In high mobile wireless broadband communication, the time and frequency dimensions of the wireless channel affect the signal, so the high mobile channel has dual selectivity. The scene of high mobile wireless communication has penetrated into every aspect of our life. It is urgent to study practical schemes and systems in order to reduce the influence of high mobile channel, improve the transmission efficiency and base on practice. It provides a new direction for theoretical research. This paper focuses on the application of rate free coding and vector multicarrier modulation in high mobile wireless communication scenarios. The main contents are as follows: this paper presents a low complexity mobile dual selective fading channel estimation method based on vector multicarrier modulation. Firstly, the mathematical form of symbol expansion of vector multicarrier modulation in CE-BEM dual selection channel is analyzed. Based on the symbol expansion structure, a pilot method is designed to insert pilot into the vector multicarrier modulation data symbol block at the transmitter and a method to estimate the CE-BEM parameters of the dual-selection channel based on the pilot at the receiving end. Compared with the traditional channel estimation method based on OFDM, the proposed method can reduce the pilot overhead and have lower computational complexity with higher mobility. An improved scheme for traditional CE-BEM modeling in vector multicarrier modulation systems is also proposed. By introducing confusion, the accuracy of channel estimation is sacrificed and the channel estimation value has better performance in the channel equalization stage. In this paper, a design scheme of rate-free vector multi-carrier communication system in high mobile scene is proposed. By analyzing the characteristics of rate free code and vector multicarrier modulation scheme, a joint coded modulation system is proposed. The scheme of data splitting into frames, the transmission mechanism, the generation and acceptance process of physical layer frames and the multilevel pipeline decoding mechanism are designed. In order to verify the feasibility of the system design, we use the software radio platform SORA programming to achieve the above system, and produce the system prototype. In the actual verification, the system can track the channel changes quickly, and adapt to the channel capacity under different mobility through the bucket water characteristic without rate code, with the help of high efficiency decoding mechanism. The approximate optimal global throughput can be obtained adaptively when mobility is changing. Finally, an adaptive multi-resolution data broadcasting system based on rate-free code is designed. Based on the concept of unequal error protection, we design an actual multi-resolution rate-free code, which makes the sender send a data stream independently without knowing the information or receiving feedback from the receiver. At the receiving end, the rate free code guarantees that the more important data information accumulates, the more the number of decoding iterations is involved. Then, according to the guaranteed minimum quality scenario and the best transmission scenario in the broadcast system, the implementation scheme of the related broadcast system is designed. By considering the calculation of the receiver and the communication ability, the adaptive data of the receiver in the broadcast scene is realized, which enables all the receivers to obtain their calculations from a single source. The maximum data quality is approximately limited by the communication capability, and the cost of the sender is reduced.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN92

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