摘要
设计了基于直接数字频率合成(DDS)的频谱分析仪。它依据外差原理,实现频率范围为1～30 MHz的信号频谱分析。通过采用DDS专用器件AD9851产生稳定的扫频信号。被测信号是经AD835与本振信号混频,再放大、滤波、检波的信号。将被测信号与扫频信号分别输入示波器的X,Y端,即可获得频谱图。此外,该仪器还具有识别调幅、调频和等幅波信号及测定其中心频率的功能。
The spectrum analyzer based on DDS is designed.Based on the heterodyne principle,the spectrum analysis can realize a signal frequency range of 1-30MHz.A stable sweep signal is generated by AD9851.The signal which the measured signal and the local signal are mixed in AD835 is amplificed,filtered,and detected.The mixed signal and the sweep signal are input into oscilloscopes X,Y to form a frequency chart.In addition,the identification of AM, FM and amplitude wave signal and the measurement of the center frequency are developed in this system.
出处
《国外电子元器件》
2008年第12期24-26,共3页
International Electronic Elements
