非平稳无线通信系统的设计与实现
发布时间：2019-05-15 21:04
【摘要】：随着无线通信网络和移动设备在人们日常工作和生活中重要性的不断提升,对更加安全可靠的无线通信技术的需求也迫在眉睫。对于传统的扩频或者跳频通信系统而言,其信号和系统都是基于各态历经和循环平稳理论来进行设计的。对于具备各态历经性和循环平稳性的信号,无论从什么时间开始观测,经过足够长时间后总是可以得到它的均值和自相关值,而且观测值越多,其观测精度越高。利用循环谱和高阶谱等分析方法,即使在很低信噪比下,仍可以检测到具备循环平稳性的通信信号的通信参数,从而完成通信信号的有效截获。本文以非平稳通信信号和系统的设计、实现和测试为主要研究内容,重点在原理样机的实现和测试方面。首先介绍了非平稳通信技术和传统扩频、跳频和跳时等通信技术的区别以及意义,还描述了目前国内外学者在相关领域的研究现状;接下来阐述了非平稳通信系统的基本原理,包括非平稳通信信号的基本构造方法和特性、物理层帧结构的结构和功能、同步与检测的基本原理等,并给出了非平稳通信系统的整体框图结构;然后给出了非平稳通信原理样机的设计结构,包括基带模块、中频/射频模块和外设等;而后分别详细介绍了非平稳无线通信发射机和接收机的信号处理流程,并按照信号处理顺序依次说明了各基带模块的原理和硬件实现方式;最后分别对内场和外场通信性能实验测试的方法和流程进行了介绍,给出了内场测试时的信噪比计量方法,以及内外场各项通信指标的测试结果。本文的主要工作内容和创新点如下:(1)针对传统通信容易被检测的弱点,设计了非平稳信号使得基于高阶量累积等方法检测信号的概率大大降低,显著增强了安全性;(2)实现了具有完整功能的非平稳通信系统原理样机。实验测试表明,在很低信噪比(-18dB)条件下,系统具有良好的误码率性能,在无纠错编码情况下接收误比特率达到10-3,且能够清晰地传输语音,验证了非平稳通信系统的可靠性;(3)在实现过程中,对非平稳无线通信系统进行了一系列针对性的改进,包括各模块时钟同步问题,解调方式优化等。
[Abstract]:With the increasing importance of wireless communication networks and mobile devices in people's daily work and life, the demand for more secure and reliable wireless communication technology is imminent. For traditional spread spectrum or frequency hopping communication systems, their signals and systems are designed based on ergodic and cyclostationary theories. For the signal with ergodicity and cyclic stationarity, the mean value and autocorrelation value can always be obtained after a long enough time, and the more the observed values, the higher the observation accuracy. By using the analysis methods of cyclic spectrum and high-order spectrum, the communication parameters of the communication signal with cyclic stationarity can still be detected even at very low SNR, so as to complete the effective interception of the communication signal. In this paper, the design, implementation and testing of non-stationary communication signals and systems are the main research contents, with emphasis on the realization and testing of the prototype. Firstly, the difference and significance between non-stationary communication technology and traditional spread spectrum, frequency hopping and time hopping communication technologies are introduced, and the current research status of scholars at home and abroad in related fields is also described. Then the basic principle of non-stationary communication system is described, including the basic construction method and characteristics of non-stationary communication signal, the structure and function of physical layer frame structure, the basic principle of synchronization and detection, and so on. The overall block diagram structure of the non-stationary communication system is given. Then the design structure of the prototype of non-stationary communication principle is given, including baseband module, intermediate frequency / RF module and peripherals. Then the signal processing flow of non-stationary wireless communication transmitter and receiver is introduced in detail, and the principle and hardware implementation of each baseband module are explained in turn according to the signal processing order. Finally, the method and flow chart of internal field and external field communication performance test are introduced, and the signal-to-noise ratio (SNR) measurement method and the test results of internal and external field communication indexes are given. The main contents and innovations of this paper are as follows: (1) aiming at the weakness that traditional communication is easy to be detected, the non-stationary signal is designed to greatly reduce the probability of signal detection based on high-order accumulation and significantly enhance the security; (2) the prototype of non-stationary communication system with complete function is realized. The experimental results show that the system has good bit error rate (BER) performance under the condition of very low signal-to-noise ratio (- 18dB). Under the condition of no error correction coding, the received bit error rate can reach 10 鈮，
本文编号：2477760
[Abstract]:With the increasing importance of wireless communication networks and mobile devices in people's daily work and life, the demand for more secure and reliable wireless communication technology is imminent. For traditional spread spectrum or frequency hopping communication systems, their signals and systems are designed based on ergodic and cyclostationary theories. For the signal with ergodicity and cyclic stationarity, the mean value and autocorrelation value can always be obtained after a long enough time, and the more the observed values, the higher the observation accuracy. By using the analysis methods of cyclic spectrum and high-order spectrum, the communication parameters of the communication signal with cyclic stationarity can still be detected even at very low SNR, so as to complete the effective interception of the communication signal. In this paper, the design, implementation and testing of non-stationary communication signals and systems are the main research contents, with emphasis on the realization and testing of the prototype. Firstly, the difference and significance between non-stationary communication technology and traditional spread spectrum, frequency hopping and time hopping communication technologies are introduced, and the current research status of scholars at home and abroad in related fields is also described. Then the basic principle of non-stationary communication system is described, including the basic construction method and characteristics of non-stationary communication signal, the structure and function of physical layer frame structure, the basic principle of synchronization and detection, and so on. The overall block diagram structure of the non-stationary communication system is given. Then the design structure of the prototype of non-stationary communication principle is given, including baseband module, intermediate frequency / RF module and peripherals. Then the signal processing flow of non-stationary wireless communication transmitter and receiver is introduced in detail, and the principle and hardware implementation of each baseband module are explained in turn according to the signal processing order. Finally, the method and flow chart of internal field and external field communication performance test are introduced, and the signal-to-noise ratio (SNR) measurement method and the test results of internal and external field communication indexes are given. The main contents and innovations of this paper are as follows: (1) aiming at the weakness that traditional communication is easy to be detected, the non-stationary signal is designed to greatly reduce the probability of signal detection based on high-order accumulation and significantly enhance the security; (2) the prototype of non-stationary communication system with complete function is realized. The experimental results show that the system has good bit error rate (BER) performance under the condition of very low signal-to-noise ratio (- 18dB). Under the condition of no error correction coding, the received bit error rate can reach 10 鈮，
本文编号：2477760
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