摘要
数字调频激励器是调频发射机的信息处理核心,直接决定发射机性能的优劣。另一方面,它又部分承担发射机故障处理及报警的职责,即调频激励器应对自身及发射机整机进行监控。在发射机运行出现故障时需进行自身调整,从而保证发射机运行的正常和安全。阐述了采用直接数字式频率合成器(DDS)软件调频方式对模拟信号进行调制。DDS产生的信号频率精度很高,且与晶体振荡器的稳定度相同,可达10-6以上。其单片机控制可以随意切换载波频率,频偏,调制度等,并且可以容易地实现。该系统的测试结果令人满意。
The digital FM actuator is a core for information processing of FM transmitter,which derectly decides the good and the bad performance of the transmitter while partially bears the responsibility for handling and alarm of the failure in the transmitter,that is to say,the FM actuator should supervise and control itself and the transmitter.When the failure occurs in the transmitter,it could adjust itself,thus to ensure the normal operation and safety of the transmitter.This paper describes how to modulate analog signals by DDS software FM.The DDS could produce the signals with high-definition frequency,and has the same stability as crystal oscillator,reaching over 10-6.SCM in control could easily switch the frequency of the carrier wave,the excursion of the frequency,and the depth of the modulation etc.Experiment on the system gives a very good result.
出处
《通信技术》
2010年第9期50-53,共4页
Communications Technology
