Design Of X-band Low Noise Amplifier

The low noise amplifier(LNA) is an important part of radar and communications system receiver front module, the main role is to amplify the antenna to receive weak signals from the air, its performance directly affects the performance of the receiver front-end. With the rapid development of civil and military microwave communication technologies and widely used, the low noise amplifier development and research has become an important focus.Due to the high electron mobility transistor(HEMT) as a Ga As FET(GaAs FET) improved, It is for the design of low-noise amplifier has many advantages, such as high frequency, low noise, high gain, it is of great advantage to microwave amplifier design. This article is based on a high electron mobility transistor to design a X-band low-noise amplifier.The main content of this paper is to complete X-band low noise amplifier design. The article first describes the significance and development of the paper at home and abroad, Then detailed analysis of the microwave circuit related knowledge and the basic theory of low noise amplifier. On the basis of these theories, this paper puts forward to increase the stability of the low noise amplifier and ways to improve the bandwidth, The combination of these methods, the choice of NEC’s high-electron-mobility transistor NE3210S01 designed X-band low noise amplifier, Dc bias circuit to use dual power supply, and use low impedance characteristics of the Fan-shaped microstrip instead of bypass capacitors and ?4/3 high-impedance line to prevent the effects of RF signal on Dc; And applying source negative feedback to increase the stability and use parallel coupled way to dc-blocking. The S parameters of the transistor imported into powerful Advanced Design System 2009 software to complete X-band low noise amplifier design, then get the optimized layout imported into Altium Designer to complete the final PCB design. In the final stage, completed the physical production of low-noise amplifier, and completed the testing and commissioning of the S-parameters, noise parameters, verify the feasibility of the design method. At the end of the paper summarizes the work done and the paper shortage, and analyzes the prospects for future work.