發(fā)布時間：2018-04-10 14:07

  本文選題：聲表面波 + 叉指換能器�。� 參考：《貴州大學(xué)》2015年碩士論文

【摘要】：隨著聲表面波(Surface Acoustic Wave,SAW)技術(shù)的快速發(fā)展,SAW器件在電子信息等領(lǐng)域得到了越來越廣泛的應(yīng)用,與此同時,對SAW器件的要求越來越高:更高的響應(yīng)頻率、更寬的帶寬、更低的插入損耗以及更小的尺寸等。由于叉指換能器(Inter Digital Transducer,IDT)是SAW器件的一個重要組成部分,要滿足上述一系列要求,改進IDT的結(jié)構(gòu),優(yōu)化其描述算法顯得尤為重要,為了改善SAW器件的特性,提高其性能,就必須從IDT的描述模型著手,首先建立數(shù)學(xué)模型,再進行模擬仿真,對比傳統(tǒng)模型的仿真結(jié)果,改進模型參數(shù)達到優(yōu)化IDT建模分析算法,滿足IDT結(jié)構(gòu)優(yōu)化為目的。改進IDT的結(jié)構(gòu),不僅可以獲得較好的旁瓣抑制和較高的頻率響應(yīng),還可以獲得較低的插入損耗。因此,對IDT結(jié)構(gòu)的改進研究是提高SAW器件性能的關(guān)鍵之一。IDT的結(jié)構(gòu)變了,用于描述IDT的傳統(tǒng)數(shù)學(xué)方法就失去了意義,這就需要找到一種適應(yīng)于新結(jié)構(gòu)的描述方法。本文是在貴州省自然科學(xué)基金項目:“聲表面波(SAW)濾波器插入損耗的補償方法研究”的基礎(chǔ)上進行的拓展研究,主要研究SAW器件的IDT的建模方法。本文首先介紹了IDT的工作原理和壓電效應(yīng)以及原有的幾種算法模型,然后闡述選擇小波函數(shù)去描述IDT結(jié)構(gòu)的依據(jù),最后在改進型?函數(shù)模型以及脈沖響應(yīng)模型的基礎(chǔ)上選擇Morlet小波函數(shù)對IDT進行數(shù)學(xué)建模,將IDT結(jié)構(gòu)參數(shù)(如指條寬度a、指間間距b、耦合長度w等)引入新建數(shù)學(xué)模型(簡稱為IDT的Morlet小波函數(shù)模型),并進行仿真驗證。對于IDT結(jié)構(gòu),再利用傳統(tǒng)的數(shù)學(xué)模型進行仿真對比,結(jié)果表明,IDT的Morlet小波函數(shù)模型比傳統(tǒng)的?函數(shù)模型更精確。本文的創(chuàng)新之處是用Morlet小波函數(shù)對IDT進行數(shù)學(xué)建模,由于Morlet小波函數(shù)是可變換的,這樣就可得出多種描述IDT結(jié)構(gòu)的Morlet小波函數(shù)模型,使得描述IDT結(jié)構(gòu)的數(shù)學(xué)模型具有靈活的可變性,分別有Morlet母小波函數(shù)模型以及進行伸縮變換后的Morlet小波函數(shù)模型,而且可以通過對IDT的Morlet小波函數(shù)模型的頻率響應(yīng)進行校正得到更精確的結(jié)構(gòu)模型,解決了原先基本?函數(shù)模型只適合規(guī)則型IDT結(jié)構(gòu)的限制。同時,分別針對IDT的結(jié)構(gòu)參數(shù)對其插入損耗以及頻率響應(yīng)影響進行仿真分析。結(jié)果表明:IDT的Morlet母小波函數(shù)模型相對于規(guī)則的IDT結(jié)構(gòu),旁瓣電平得到了很好的抑制,插入損耗較小。
[Abstract]:With the rapid development of surface acoustic wave surface Acoustic wave (saw) technology, saw devices have been more and more widely used in the field of electronic information and other fields. At the same time, the requirements for SAW devices are becoming higher and higher: higher response frequency, wider bandwidth, and so on.Lower insertion loss and smaller dimensions, etc.Because InterDigital Digital Transducer (IDT) is an important part of SAW device, it is very important to improve the structure of IDT and optimize its description algorithm in order to meet the above requirements. In order to improve the characteristics and performance of SAW device, it is very important to improve the structure of IDT.It is necessary to start with the description model of IDT, first establish the mathematical model, then carry on the simulation, compare the simulation results of the traditional model, improve the model parameters to optimize the IDT modeling analysis algorithm, meet the purpose of IDT structure optimization.The improved structure of IDT can not only obtain better sidelobe suppression and higher frequency response, but also obtain lower insertion loss.Therefore, the research on the improvement of IDT structure is one of the key factors to improve the performance of SAW devices. The structure of SAW device has changed, and the traditional mathematical method used to describe IDT has lost its significance. Therefore, it is necessary to find a description method suitable for the new structure.This paper is based on the project of Guizhou Provincial Natural Science Foundation, "study on the compensation method of saw filter insertion loss", mainly on the IDT modeling method of SAW device.This paper first introduces the working principle of IDT, the piezoelectric effect and several original algorithm models, then expounds the basis of choosing wavelet function to describe the structure of IDT, and finally improves the structure of IDT.On the basis of function model and impulse response model, Morlet wavelet function is selected to model IDT.The structural parameters of IDT (such as the width of the strip a, the distance between fingers b, the coupling length w etc.) are introduced into the new mathematical model (Morlet wavelet function model called IDT for short) and verified by simulation.For the IDT structure, the traditional mathematical model is used to carry out the simulation. The results show that the Morlet wavelet function model is better than the traditional Morlet wavelet function model.The function model is more accurate.The innovation of this paper is the mathematical modeling of IDT with Morlet wavelet function. Because the Morlet wavelet function is transformable, various Morlet wavelet function models describing IDT structure can be obtained.The mathematical model of describing IDT structure has flexible variability, which includes Morlet mother wavelet function model and Morlet wavelet function model after extensional transformation, respectively.And by correcting the frequency response of IDT's Morlet wavelet function model, we can get a more accurate structural model, and solve the original basic?The function model is only suitable for the restriction of regular IDT structure.At the same time, the influence of structure parameters on insertion loss and frequency response of IDT are simulated.The results show that compared with the regular IDT structure, the sidelobe level of the Morlet mother wavelet function model of WIDT is well suppressed and the insertion loss is relatively small.
【學(xué)位授予單位】：貴州大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN65

【參考文獻】

相關(guān)期刊論文 前1條

1 肖尚輝,徐繼麟;無線通信用SAW濾波器的分析與設(shè)計[J];電子科技大學(xué)學(xué)報;2002年05期

，

本文編號：1731516