DCR系统4FSK调制解调器的研究与实现

发布时间：2018-02-27 20:08

本文关键词： DCR 4FSK调制解调软件无线电　出处：《沈阳航空航天大学》2014年硕士论文　论文类型：学位论文

【摘要】：如今的专业无线通信领域,数字集群对讲机是最重要的通信方式。在刚刚过去几十年里,模拟对讲机占据了大部分市场。但随着人们对无线通信质量要求的提高以及频谱资源的日益高涨,模拟对讲机已经很难适应现在的通信环境。因此,我国和全球的对讲机正在由模拟向数字转变。数字对讲机不仅能够完成模拟对讲机的基本通信功能,同时能够实现文本信息等数据传输功能。数字信号易通过计算机处理,因此数字对讲机的通讯能力、功能和质量就要比模拟对讲机要好,可以满足现代专用无线通信的需要。本文研究日本无线电工业协会2010年最新修订的DCR数字对讲机标准,它采用4FSK调制解调方式,FDMA技术,码元速率为4.8kbps,可以同时进行数据和语音通信。针对DCR标准设计的调制解调系统,重点研究4FSK频率调制与解调原理、4FSK基带信号处理关键理论,并在软件无线电平台上具体实现DCR系统。本文首先介绍了DCR标准的4FSK调制解调系统的理论方案,阐述4FSK调制和解调的基本原理,介绍了相关基带信号处理的理论;其次,提出了DCR调制解调系统的具体的设计方案。对该系统中的基带信号处理模块的基本理论进行设计与仿真,主要包括均方根余弦滚降滤波器、Isinc滤波器和帧同步检测器的设计。之后对DCR系统射频模块的4FSK频率调制解调方案进行仿真验证,分析相干解调与非相干解调算法的误码率曲线,确定最终方案。然后,搭建的DCR系统4FSK调制解调器软件无线电平台,阐述数据采集模块设计、FIR滤波器的CSD量化编码设计,并在系统平台上对基带调制解调系统进行实现;最后,介绍了DCR系统平台硬件结构,对平台中主要模块进行测试,给出测试结果。
[Abstract]:Digital trunked talkies are the most important means of communication in the field of professional wireless communications today. Analog interphone has occupied most of the market. However, with the improvement of wireless communication quality and the rising of spectrum resources, it is very difficult for analog interphone to adapt to the current communication environment. The interphone of our country and the whole world is changing from analog to digital. Digital interphone can not only complete the basic communication function of analog interphone, but also realize the function of data transmission, such as text information. Therefore, the communication capability, function and quality of the digital interphone must be better than that of the analog interphone, and it can meet the needs of the modern private wireless communication. This paper studies the DCR digital interphone standard revised by the Japan Radio Industry Association in 2010. It adopts 4FSK modulation and demodulation mode and the symbol rate is 4.8kbps. it can communicate with voice and data at the same time. According to the modulation and demodulation system designed by DCR standard, the key theory of 4FSK frequency modulation and demodulation and 4FSK baseband signal processing is studied emphatically. Firstly, this paper introduces the theoretical scheme of 4FSK modulation and demodulation system based on DCR standard, expounds the basic principle of 4FSK modulation and demodulation, and introduces the theory of related baseband signal processing. The specific design scheme of DCR modulation and demodulation system is put forward, and the basic theory of baseband signal processing module in this system is designed and simulated. It mainly includes the design of ISINC filter and frame synchronization detector, and then simulates the 4FSK frequency modulation and demodulation scheme of RF module in DCR system, and analyzes the error rate curve of coherent demodulation and non-coherent demodulation algorithm. Then, the software radio platform of 4FSK modem in DCR system is built, and the design of CSD quantization coding of Fir filter is expatiated. Finally, the baseband modulation and demodulation system is implemented on the platform of the system. The hardware structure of DCR system platform is introduced. The main modules of the platform are tested and the test results are given.
【学位授予单位】：沈阳航空航天大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN915.05

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