中频数字接收机及关键技术研究

高速率的数字系统中常采用降速抽取的方法减轻数据运算量,造成信息的丢失.为确保测量精度,该文基于先进先出(FIFO)作数据缓存的方法,设计了一个数字中频幅相接收系统,对数字本振、数字下变频、幅相计算等关键技术进行了讨论和仿真分析.给出了对调幅、调制脉冲信号解调的试验结果,动态范围＞50 dB,幅度波动＜0.25 dB.

Research on Critical Technology of Intermediate Frequency Digital Receiver

Decimation is always employed to reduce computation in digital receiver with high speed data rate.But this method will cause data lost.In order to increase the accuracy of measurement,FIFO using for data buffer was proposed in this paper.A digital receiver was designed.Critical technologies such as NCO,DDC and computation of the amplitude and phase were discussed in detail.Simulation results were given.Also the test results for demodulating the AM,pulse signal were shown that dynamic range was greater than 50 dB,ripple of amplitude was less than 0.25 dB.