Develop A Module That Transforms Broadband To Narrowband Under S Band

Receiving module is an important component of radar,communication system and guidance system.With the rapid development of these systems and the wide range of requirements,the application scope of receiving modules is gradually expanding.The development of receiving modules has also become an indispensable field.At the same time,the receiving module also derives a variety of structures based on different applications and requirements.Among them,the superheterodyne receiver structure has been used till now because of its outstanding advantages.This thesis adopts a superheterodyne architecture to implement the S-band broadband down-conversion narrowband receiver front-end module.This thesis first introduces the development history of receiving front-end modules and the development status of S-band receiver modules at home and abroad,and analyzes the significance and background of the topic.Then introduced the basic principle of different implementation structure of the receiving module,compared and analyzed the advantages and disadvantages of different receiving module structure,and analyzed in detail the typical indicators of the performance of the receiving module.Combining with the topic requirements,the superheterodyne receiving structure is finally selected as a specific structure for implementing this receiving front-end module.In order to meet the overall index requirements,the design method from the top down,combined with the difficulty of the actual design and other factors,the system indicators assigned to different modules,focusing on the PIN diode switching attenuation network and low noise amplifier design.In the rest of this thesis,the application principle of PIN diodes in the switch is described in detail,the switch specifications are introduced,and a single-pole,double-throw switch attenuation network using a PIN diode is designed.In addition,because the low-noise amplifier is an important part in the receiving module,this thesis elaborated the principle and implementation process of the low-noise amplifier,and analyzed the indicators and design requirements of the low-noise amplifier.At the same time,the simulation process of PIN diode switch attenuation network and low noise amplifier designed by Keysight's ADS simulation software is given.At the end of this thesis,the other devices in the down-conversion module are introduced,and the link simulation diagram and test results of the front-end module are given.Finally,the radio frequency signal of-50 dBm ~0 dBm at 2.2GHz-3.8GHz is down-converted.For the purpose of 2 GHz ± 15 MHz power-30 d Bm IF signal.