Design Of Microwave Broadband Low Noise Amplifier

Since entering the 21 st century,the way of information transmission has changed from traditional telegrams,wired telephones to mobile phones and tablet.All of which are inseparable from the rapid development of wireless communications.In modern society,people want to collect and transmit information quickly,which poses a huge challenge to the performance of transceivers in the microwave frequency band.As the front-end device of the receiving system,the low noise amplifier has a far greater influence on the performance of the entire receiving system.Therefore,the development of microwave broadband low-noise amplifiers with high performance has become an urgent need in the field of wireless communication.In this paper,two microwave broadband low noise amplifiers are designed.The first broadband LNA is based on 0.15μm Ga As PHEMT process and operates from 4GHz to 18 GHz.The circuit improves the traditional distributed structure,combines distributed amplification and coupling amplification,and improves the gain on the premise of ensuring high bandwidth.The second broadband low-noise amplifier is based on 40 nm CMOS technology,and operating from 21 GHz to 35 GHz.The circuit adopts three-stage cascade,the first stage is a cascode structure,and the second stage and the third stage adopt a pseudo-differential structure.In addition,in order to expand the bandwidth and improve the stability,techniques such as staggered peak matching,series feedback and capacitance neutralization are adopted.The post-simulation results of the layout show that in the range of 4～18GHz,the first LNA has a maximum gain of 22.44 d B,gain flatness of 1.02 d B,noise figure variation range of2.77 d B to 4.10 d B,input and output reflection coefficients are less than-10 d B.Unconditionally stable in the entire frequency band,the saturated output power is 19.841 d Bm.The second LNA has a maximum gain of 25.47 d B in 21～35GHz,gain flatness is 0.745 d B,noise figure does not exceed 4.37 d B,and input and output ports all maintain good matching,it is unconditionally stable in the entire frequency band,and the compression point of input 1d B is-18.74 d Bm.While achieving high gain,it meets the requirements of a wide frequency range.