无线宽带OFDM信号的阵列化接收机制设计与优化

发布时间：2018-08-09 16:01

【摘要】：无线网络性能的提升,一直是学术界和产业界关注的热点问题。二十一世纪已经正式进入信息时代,人们的日常生活对信息交互、数据传输的依赖程度前所未有。无线通信终端种类和数目越来越多,无线通信数据传输量与日俱增,数据产生和传播的增长速度已经远远超过了无线通信技术的发展速度,给无线通信系统的传输速率能力带来了极大的挑战。增加无线通信的带宽是能够大幅提升无线通信速率的最直接和最有效的手段。近年来,无线通信已经呈现的明显的宽带化趋势,无线信道带宽的量级已经从MHz量级走向GHz量级,再到sub-THz量级,这一趋势还将持续维持。传统的无线通信收发机制依靠增加单个设备的通信带宽来实现高速率无线通信传输,硬件实现复杂度随之增高。受限于当前的滤波器、ADC等硬件制造水平,用传统设计思路实现GHz量级的无线信号的接收,造价极高、难度极大。针对传统无线接收机制实现宽带高速无线通信面临的挑战,本文创新的提出了一种针对无线宽带OFDM信号的阵列化接收机制STTGR,并对其进行了优化。STTGR是一种软件和硬件结合的信号接收机制,基本思路是,前端利用固定、有限带宽的窄带设备阵列作为硬件前端,设计“窄带拼宽带”的数据融合算法进行后处理,实现无线宽带OFDM信号的接收。本文的主要工作和创新点为:1)STTGR阵列化接收机制的设计。突破当前无线通信接收端只能在固定带宽工作的局限性,设计了一种带宽可扩展的阵列化无线信号接收机制STTGR,为新一代无线通信的发展提供了创新思路。STTGR的基本思想是利用多个窄带设备组成接收阵列,每个窄带设备处理宽带信号一个子频带上的信号,再利用软件算法实现时间对齐、数据融合等后处理,实现宽带信号的全频段覆盖接收。STTGR是一种软件和硬件结合的信号接收机制,通过软件处理实现后期数据处理,降低了硬件实现复杂度。第三章给出了该机制设计方案、理论推导及仿真实验结果。2)STTGR阵列化接收机制的优化。将阵列中的窄带设备视为多个用户,阵列化接收的问题转化为多用户协作接收的问题。借鉴多用户分集的思想,充分利用无线信道的选择性衰落特性和多用户动态性,按照优化目标在阵列中窄带设备之间重新分配宽带OFDM信号的子载波,对本文提出的阵列化接收机制STTGR提出两种优化方案和四种优化算法。一种优化方案是最小化传输误比特率,设计了基于贪心策略的子载波分配算法和轮回分配子载波算法;另一种优化方案是优化系统的功率利用率,设计了基于遗传算法的子载波分配算法和基于粒子群优化的子载波分配算法。第四章给出了设计的优化算法、理论推导及和仿真实验结果。本文的设计的阵列化接收机制STTGR主要特点是,接收带宽可扩展,设备规模可伸缩,具有面向未来无线通信的可持续发展能力,能够从根本上解决无线通信面临的挑战。研究成果有望成为无线通信领域的原创性技术突破,为宽带通信提供研究思路和技术支撑,具有重要的理论意义和工程价值,应用前景广阔。
[Abstract]:The enhancement of wireless network performance has always been a hot issue in the academic and industrial circles. In twenty-first Century, it entered the information age. People's daily life has an unprecedented dependence on information interaction and data transmission. The variety and number of wireless communication terminals are increasing, and the amount of data transmission in wireless communication is increasing with the day. The growth rate of birth and communication has far exceeded the speed of wireless communication technology, which has brought great challenges to the transmission rate capability of wireless communication systems. Increasing the bandwidth of wireless communication is the most direct and effective means to greatly improve the rate of wireless communication. With the trend of transformation, the magnitude of the wireless channel bandwidth has gone from MHz to the order of GHz, and then to the magnitude of sub-THz. This trend will continue to maintain. The traditional wireless communication and transceiver mechanism relies on increasing the communication bandwidth of a single device to achieve high rate wireless communication transmission, and the complexity of hardware implementation increases. Limited to the current filter, ADC Such as the level of hardware manufacturing, using traditional design ideas to realize the reception of GHz level wireless signals, the cost is very high and the difficulty is very difficult. In view of the challenges facing the traditional wireless receiving mechanism to realize broadband and high-speed wireless communication, a new array receiving mechanism for wireless broadband OFDM signals, STTGR, is proposed, and.S is optimized. TTGR is a combination of software and hardware signal receiving mechanism, the basic idea is that the front end uses a fixed, limited bandwidth narrow band device array as a hardware front end, and designs a "narrow band" data fusion algorithm for post-processing, realizing wireless broadband OFDM signal receiving. The main work and innovation of this paper are: 1) STTGR array The design of receiving mechanism, breaking through the limitation that the current wireless receiver can only work in fixed bandwidth, designed a bandwidth extensible array wireless signal receiving mechanism STTGR, which provides an innovative idea for the development of a new generation of wireless communications. The basic idea of.STTGR is to make use of multiple narrow band devices to form a receiving array, each narrow. With the equipment processing the signal in a subband of broadband signal, and using software algorithm to realize time alignment, data fusion and so on, the full band coverage receiving.STTGR of broadband signal is a kind of signal receiving mechanism combined with software and hardware, and the later data processing is realized through software processing, and the complexity of hardware implementation is reduced. The three chapter gives the design scheme of the mechanism, the theoretical deduction and the result of the simulation experiment.2) the optimization of the STTGR array receiving mechanism. The narrowband devices in the array are regarded as multiple users, and the problem of array reception is transformed into the problem of multi user cooperation receiving. As well as multiuser dynamics, two optimization schemes and four optimization algorithms are proposed for the array reception mechanism proposed in this paper by redistributing the subcarriers of the wideband OFDM signal between the narrowband devices in the array. One optimization scheme is to minimize the transmission error rate, and designs a subcarrier allocation based on the greedy strategy. The subcarrier algorithm of the method and the cycle distribution; another optimization scheme is to optimize the power utilization of the system. The subcarrier allocation algorithm based on genetic algorithm and the sub carrier allocation algorithm based on particle swarm optimization are designed. The fourth chapter gives the design optimization algorithm, the theoretical deduction and the simulation experiment results. The array reception of the design in this paper is designed. The main features of the mechanism STTGR are that the receiving bandwidth is extensible, the scale of the equipment is scalable, the sustainable development ability facing the future wireless communication and the challenge to the wireless communication can be solved fundamentally. The research results are expected to be the original technological breakthrough in the field of wireless communication, and provide research ideas and technical support for broadband communication. It has important theoretical significance and engineering value, and has broad application prospects.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.53

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