The Design Of The Broadband Low Noise Amplifier

This paper firstly introduces the basic theory of the low-noise amplifier design,and gives several circuit formfor the design of wideband low-noise amplifier, andcontrast their characteristics, choose to use the circuit in the form of negative feedbacknetwork to complete the design. On this basis, you will see the whole process of awideband low-noise amplifier’s design, simulation, production, measurement anddebugging.Firstly, we use EDA software ADS to design a single stage amplifier with thenegative feedback technology, and getting the simulation results; then create the actualcircuit, measurement and debug it to get the measured data, by comparing to thesimulation data and measured data we found the single stage low-noise amplifier withnegative feedback can not achieve the required indicator; finally we modify the design,by cascading the single–stage low noise amplifier based on a negative feedbacknetwork to constitute the two stage low-noise negative feedback amplifier, and add anattenuation network at the output.After getting the ideal simulation results, we producethe actual circuit and then make the measurement and debugging. Finally, in the30MHzto1350MHz operating frequency, the low noise amplifier approaches the designinggoal with a gain of20dB with the flatness less than2.5dB, and the noise figure is lessthan3.4dB, and the VSWR is less than1.5.