The Design Of Dual-Band Variable Gain LNA Applied In TPMS

In recent years,these accidents caused by tire-bursting have occurred frequently.In order to ensure the safety of the vehicle,the wireless tire Pressure monitoring system is assembled in the automobile,and the real-time monitoring of tire pressure is increasing important.Then,in order to adapt to different application occasions,the receiver gain and frequency band can be flexibly configured,the low noise amplifier as the key module,the noise coefficient,gain and linearity of the TPMS system direc-tly affect the overall performance.This paper is compared the low noise amplifier with different structure,finally,completes the design of a two-band,variable gain and low noise amplifier used in tire pressure monitoring system.Firstly,this paper introduces the structure of TPMS system and analyzes the working principle of system.Then,in the ADS software,calls link budget Tool dock-ing link system verification,deduces the key design index of low noise.By the compr-omise of input matching,noise coefficient,gain,linearity and stability,the low noise amplifier adopts a two-way parallel common gate circuit structure.Two-band variable gain LNA includes low frequency channel LNA_LF,high frequency channel LNA_HF,gain adjustment and bias circuit.Among them,the high and low frequency channel re-alize the input matching index of double frequency band by adopting the common gate structure.And it adopts the differential circuit of common source and gate to obtain the high isolation and low two harmonic distortion.And adopts 2-bit control signal to adjust the load so that it can realize four-block gain adjustable.Finally,based on the GSMC 0.18 ?m,we can complete the layout design by using the Virtuoso.Above the Linux working environment,we can extract the parasitic parameters by using the Calibre software under the Cadence platform.And the rear simulation of the low noise amplifier is accomplished in the Spectre RF.These simulation results show that the LNA voltage gain,respectively,is 11.3,12.9,14.6,15.7dB.noise figure is 4.23,4.05,3.82,3.48dB,IIP3>-3dBm.when working in 433MHz band.When working in the 915MHz band,the LNA voltage gain is 14.2,16,17.6,19.1dB.the noise figure is 3.32,3.29,3.27,3.24dB,IIP3>-3dBm respectively.S11 are less than-20dB and the layout area is 215?m X 270?m,which meet the requirements of tire pressure monitoring system.