Precision Electronically Controlled Attenuator Design And Development

Today,the advanced attacked weapons give challenge to the modern radar. They need higher function of modern radar than before. Most modern radars are a high resolution system,which uses amplitude and phase information to achieve main function .In order to evaluate the performance of a radar,the radar simulator,as an important part of a radar verifying system,must possess good characteristics,and its output signal must have high stability and accuracy. Therefore there is a high demand for the electrically tuned attenuator(ETA).This paper introduces some practicable way of ETA,presents the principle of each method and compares their virtues and shortcomings. Among them,the VCA(voltage controlled amplify) becomes prominent for its good characteristics,such as wide output dynamic range,low nonlinear distortion,flat amplitude-frequency characteristics,high amplitude resolution. And with the development of integrated circuit technology,this method is becoming more and more flexible. High speed circuit is widely used,in order to obtain high performance,quantitative analysis about the PCB(print circuit board) circuit is fully described,and efficient shield,bypass,ground is used in design the High resolution circuit.We make the circuits of each part and the corresponding analysis,put forward some suggestion for improving the performance of the system. The circuits have been put into practice,and proved to work well.