数模同播FM发射机的设计与实现  

Implementation and Design of Digital - Analogue Simulcast FM Transmitter

作　　者：徐文波[1] 赵娟[1] 黎薇[1] 陈明[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,广西桂林541004

出　　处：《电声技术》2012年第4期63-66,共4页Audio Engineering

基　　金：国家自然科学基金项目(61077036);广西自然科学基金青年基金项目(2011GXNSFB018069);广西研究生教育创新计划资助项目(2010105950810M13)

摘　　要：设计了一种基于数模同播结构的新型FM发射机,该结构可以实现在现有模拟FM广播频段上同时传输数字音频广播信号。该结构由FPGA和两路ADC组成,基于NiosⅡ软核CPU搭建控制平台,利用DDS和IFFT的原理分别实现模拟FM调制和数字OFDM调制,最后合路实现数模同播。通过实验证明,该结构具有实现简单、不需要申请新的频谱资源和拓展高音质数字广播业务的特点,可以实现模拟/数字调频同播运行,为FM广播由模拟向数字平滑过渡提供了实验验证。A new FM transmitter based on digital -analogue simulcast structure is proposed in this paper. On the premise of not affecting the existing analogue broadcasting, the digital - analogue simulcast provides high - resolution digital audio broadcasting and data services with its analogue broadcasting spectrum. The system can be divided into the FPGA module and dual - ADC module, which consists of a control module based on the Nios II CPU. Analogue FM signal can be generated by the principle of DDS and digital OFDM signal can be also generated by the principle of IFFT, and then the digital-analogue simulcast signal can be generated at last. Experimental results show that the structure is easy to implement and has the high quality digital broadcasting services without new spectrum resources. Analogue and digital signals can be broadcast synchronously in this experiment platform, which provides an experimental verification for smooth transition from analogue broadcasting to digital broadcasting.

关 键 词：数模同播 FM OFDM AD9957 

分 类 号：TN93[电子电信—信号与信息处理]