The Design And Realization Of Signal Conditioning Modules For Signal Acquisition System

The applications of wideband signal acquisition system is very broad. Theperformance of first stage of the wideband signal acquisition system, constituted by thelow noise amplifier signal conditioning modules, will directly affect the performance ofthe overall system. On certain occasions, some signal the wideband signal acquisitionsystem should gathering is of a wide range of frequency, amplitude uncertainty, thusrequiring amplification in the signal processing module circuit have the feature of widebandwidth, low noise, gain selectable. This thesis focuses on how to realize amplifierdesign with low noise, wide bandwidth and low noise. Finally, we designed a multi-stagecascade of wideband low-noise amplifier using the RF transistor.Firstly, the paper describes the overall design of the wideband signal acquisitionsystem, including the weak sensor signal processing module and the signal acquisitionmodule. The purpose of this part is to obtain the clear needs of the signal conditioningmodules. Then, the paper systematically introduces the basic theory of the transistoramplifier and RF circuit design. Finally, based on the theories above, a design withmulti-stage cascade RF amplifier is presented and realized on board-level implementations.This study focuses on the following:This paper in-depth studies the theory of wideband low noise amplifier design. weselect Avago’s low-noise, wide bandwidth RF amplifier transistor ABA51563as the coreof the circuit design, then use the simulation software ADS2009designing and analyzingthe performance of the broadband cascaded amplifier circuit.Broadband cascaded amplifier PCB circuit board design. As a wide range of signaloperating frequency, the wideband circuit board layout design is different fromlow-frequency circuit board design. RF PCB circuit board material selection, componentselection, layout and wiring methods were studied. The paper presents a design ofbroadband low-noise cascade amplifier PCB circuit board basis on combination with rulesand circuit characteristics of the multi-stage cascade circuit. Then we manufactured thefront-end signal conditioning modules for wideband signal acquisition system, achieving gain of20dB/40dB/60dB, wideband frequency range, low noise amplification. UsingVector network analyzer tests the gain, the standing wave ratio, and linearity performanceof the modules in the lab environment. Finally, the actual signal conditioning module testresults and simulation results are compared and analyzed.