文章主要介绍一种现场可编程逻辑门阵列(Field Programmable Gate Array,FPGA)控制数字频率合成器(Direct Digital Synthesizer,DDS)实现四进制移频键控(Quaternary Frequency Shift Keying,4FSK)&频率调制(Frequency Modulation,FM...文章主要介绍一种现场可编程逻辑门阵列(Field Programmable Gate Array,FPGA)控制数字频率合成器(Direct Digital Synthesizer,DDS)实现四进制移频键控(Quaternary Frequency Shift Keying,4FSK)&频率调制(Frequency Modulation,FM)调制载波的设计方案,给出技术指标参数、硬件组成框图以及信号处理流程,对4FSK的调制信号和FM信号产生的实施方法进行探讨,并对电路框图中的关键器件进行国产化设计选型。展开更多
DMR(Digital Mobile Radio)是ETSI在2004年提出的集群通信系统标准,作为从模拟通信到数字通信过渡的桥梁,已经得到了广泛的使用。本文基于软件无线电思想,提出了基于DMR协议的数字对讲机的解决方案,并通过验证系统的物理链路的搭建、以...DMR(Digital Mobile Radio)是ETSI在2004年提出的集群通信系统标准,作为从模拟通信到数字通信过渡的桥梁,已经得到了广泛的使用。本文基于软件无线电思想,提出了基于DMR协议的数字对讲机的解决方案,并通过验证系统的物理链路的搭建、以及语音单呼、语音组呼DMR标准业务的实现对解决方案的可行性进行了验证。系统中用到的关键技术如4CP-FSK调制解调技术、码元同步与帧同步、基带信号处理等,各模块单独封装,弱耦合,丰富了软件无线电系统的波形组件库,也可作为软核便于集成或者复用到其他系统中。本文网络版地址:http://www.eepw.com.cn/article/145480.展开更多
We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the t...We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the transmission speed in each sub-carriers and increase the transmission performance, comparing with the 2-FSK signal. The transmission performance of the 4-ary FSK was demonstrated after a 50 km single mode fiber. The results showed that the 4-ary FSK can realize error-free transmission. Moreover, we analyzed the influence of factors （such as disperse compensation and demodulation bandwidth） on the transmission performance in this paper. The analysis of the influenced factors can provide a theoretical basic for experiment.展开更多
文摘设计了一种基于FPGA器件的4FSK调制器.在总体的设计过程中,完成了4FSK调制器所需的各个模块的设计及其硬件的实现,其中包括分频模块、M序列生成模块、串并转换模块、载波频率选择模块、SIN-ROM存储模块和D/A转换控制模块.利用Quartus II软件编写了testbench测试程序并调用modelsim软件及Signal-Tap II Logic Analyzer逻辑分析仪对4FSK调制器进行了仿真与实时测试,结果较为准确,能够完成调制所需的工作任务,因此该4FSK调制器的设计拥有一定的应用价值.
文摘文章主要介绍一种现场可编程逻辑门阵列(Field Programmable Gate Array,FPGA)控制数字频率合成器(Direct Digital Synthesizer,DDS)实现四进制移频键控(Quaternary Frequency Shift Keying,4FSK)&频率调制(Frequency Modulation,FM)调制载波的设计方案,给出技术指标参数、硬件组成框图以及信号处理流程,对4FSK的调制信号和FM信号产生的实施方法进行探讨,并对电路框图中的关键器件进行国产化设计选型。
文摘DMR(Digital Mobile Radio)是ETSI在2004年提出的集群通信系统标准,作为从模拟通信到数字通信过渡的桥梁,已经得到了广泛的使用。本文基于软件无线电思想,提出了基于DMR协议的数字对讲机的解决方案,并通过验证系统的物理链路的搭建、以及语音单呼、语音组呼DMR标准业务的实现对解决方案的可行性进行了验证。系统中用到的关键技术如4CP-FSK调制解调技术、码元同步与帧同步、基带信号处理等,各模块单独封装,弱耦合,丰富了软件无线电系统的波形组件库,也可作为软核便于集成或者复用到其他系统中。本文网络版地址:http://www.eepw.com.cn/article/145480.
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. 61471179 and 61301226）, and the High Technology Research and Development Program of China （No. 2015AA016904）.
文摘We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the transmission speed in each sub-carriers and increase the transmission performance, comparing with the 2-FSK signal. The transmission performance of the 4-ary FSK was demonstrated after a 50 km single mode fiber. The results showed that the 4-ary FSK can realize error-free transmission. Moreover, we analyzed the influence of factors （such as disperse compensation and demodulation bandwidth） on the transmission performance in this paper. The analysis of the influenced factors can provide a theoretical basic for experiment.
