The Research On Low Noise Amplifier Component With Switching And Limiting Function

In the receiving system of communication,radar and electronic countermeasures,the withstand power and low noise are the two most important indexes.With the development of technology,some systems are required to bear more and more power,and the noise factor is required to be lower and lower.This requires higher requirements for the circuit design and the material and technology of the device.This project is applied to the receiving system of a certain project.Its role is to improve the system to prevent the receiving system from being burned by the launch system,and to provide the function of low noise amplification,improve the system's ability to receive small signals,and improve the sensitivity of the whole system.The circuit design is based on the components,and through the circuit design,the characteristics of the components are displayed as the required electrical characteristics.So the basic phase of the circuit design is to make a full understanding of the components,and have a clear understanding of the principle and electrical characteristics of the components.Based on the foundation,this paper introduces some basic knowledge of diodes and transistors.Next,we introduce the basic knowledge of switch circuit,limiter circuit and amplifier circuit,and finally develop the sample.A low noise amplifier component with switching and limiting function is developed in this paper.We first designed and developed three sub modules of high-power switch,low-power anti parallel limiter and low noise amplifier,and then we made overall layout and structure design.In the design,we use the design software to establish a more accurate model and improve the accuracy of the design.The design model of this paper is frequently-used and referable.The component adopts hybrid integrated circuit technology.It takes full account of the characteristics of heat dissipation and miniaturization,and realizes the integration of three functions of switch,limiter and amplification.The final test result is that the component bears the power of 1000W(maximum pulse width:200us;duty ratio:10%),and the noise factor is 1.1dB.