摘要
该系统是由宽带放大器OPA842、可变增益放大器VCA824以及电流型运放THS3202组合而成的增益可控射频放大器,可实现12d B^40d B增益步进可调。系统由三级构成。OPA842实现两倍固定增益放大构成前级放大器,对输入信号做放大处理。中间级电压增益控制和增益步长控制电路由VCA824通过DA模块实现。末级由THS3202实现功率放大输出。该系统使用同轴线输入信号,最大限度地降低外部干扰。经测试,整个系统性能稳定,控制效果好。
The system composed of broadband amplifier 0PA842, variable gain amplifier VCA824 and current gain amplifier THS3202 is controllable RF amplifier gain. Rf amplifier gain can be adjusted step-by-step from 12dB to 40 dB. The system consists of three level. Prime amplifier competed by 0PA842 realizes 2 times fixed gain amplification to enlarge the input signal. Intermediate level gets command of voltage gain and gain step length by VCA824 and DA model. The last level implemented power amplifier output through THS3202. The input signal is given by coaxial line and reduce the external interference to the limit. After testing, the whole system has stable performance and good control effect.
出处
《电子测试》
2015年第10期19-22,共4页
Electronic Test
基金
猪行为监测系统的设计与研究工作
项目编号(20142-19)
