本文選題：矢量信號(hào)發(fā)生 + 基帶調(diào)制��； 參考：《電子科技大學(xué)》2014年碩士論文

【摘要】：隨著移動(dòng)通信技術(shù)的高速發(fā)展,數(shù)字調(diào)制方式的日益豐富,硬件實(shí)現(xiàn)數(shù)字調(diào)制功能的復(fù)雜度和難度也日益提高,然而把調(diào)制解調(diào)功能用軟件的方式來完成,極大地提高了通信系統(tǒng)設(shè)計(jì)的靈活性。同時(shí)縮短了工程的開發(fā)周期、降低了開發(fā)成本,并且具有較高的穩(wěn)定性、易用性和可擴(kuò)展性。如今在數(shù)字通信系統(tǒng)的測(cè)量和調(diào)試過程中,矢量信號(hào)發(fā)生器已被廣泛應(yīng)用,基帶信號(hào)發(fā)生裝置是矢量信號(hào)源中至關(guān)重要的部件,它為數(shù)字I/Q調(diào)制提供了相應(yīng)的基帶信號(hào),同時(shí)其產(chǎn)生的數(shù)字調(diào)制基帶信號(hào)也可以直接作為信號(hào)輸出。本文設(shè)計(jì)不同調(diào)制類型的矢量基帶信號(hào)通過通用軟件無線電平臺(tái)USRP2(Universal Software Radio Peripheral)上變頻后發(fā)射。本文主要的研究?jī)?nèi)容如下:1、在用戶自定義碼源序列的基礎(chǔ)上,對(duì)偽隨機(jī)序列碼源的生成技術(shù)進(jìn)行了研究,提供了不同的偽隨機(jī)序列碼源選擇,PN9、PN13、PN25等。2、基于I/Q調(diào)制原理對(duì)幾種常規(guī)數(shù)字調(diào)制格式如MASK、MFSK、MPSK、MQAM等進(jìn)行了分析研究,建立了碼源信息與基帶信號(hào)之間對(duì)應(yīng)的星座映射關(guān)系,實(shí)現(xiàn)了多進(jìn)制調(diào)制方式的基帶信號(hào)調(diào)制輸出,并實(shí)現(xiàn)了人為的疊加信道噪聲,人為的加入I/Q畸變。3、對(duì)基帶信號(hào)生成中的關(guān)鍵數(shù)字成型濾波技術(shù)進(jìn)行了研究,成型濾波器主要減小了基帶信號(hào)傳輸過程中的碼間干擾,提高了頻譜的利用率。在本文設(shè)計(jì)中直接調(diào)用LabVIEW里的升余弦濾波和FIR濾波等子vi來搭建基帶信號(hào)成型濾波器,并通過MATLAB對(duì)濾波器成型效果進(jìn)行了仿真驗(yàn)證。4、搭建測(cè)試平臺(tái),對(duì)設(shè)計(jì)進(jìn)行了功能驗(yàn)證和信號(hào)質(zhì)量測(cè)試,證實(shí)了本次設(shè)計(jì)的可行性。經(jīng)過最終測(cè)試對(duì)比,基于軟件無線電的數(shù)字調(diào)制基帶信號(hào)可滿足發(fā)生ASK、FSK、PSK、QAM等多種調(diào)制格式信號(hào)的需求,最高采樣率可達(dá)20MS/s,最高符號(hào)率可達(dá)25MHz,通過對(duì)信號(hào)EVM和MER的分析驗(yàn)證,EVM值均小于6%,設(shè)計(jì)滿足要求。
[Abstract]:With the rapid development of mobile communication technology and the increasingly rich digital modulation mode, the complexity and difficulty of realizing digital modulation function in hardware is increasing. However, the modulation and demodulation function is accomplished by software. The flexibility of communication system design is greatly improved. At the same time, it shortens the development cycle, reduces the development cost, and has high stability, ease of use and expansibility. In the process of measurement and debugging of digital communication system, vector signal generator has been widely used. Baseband signal generator is an important component of vector signal source, which provides the corresponding baseband signal for digital I / Q modulation. At the same time, the digital modulation baseband signal can also be directly output as the signal. In this paper, vector baseband signals of different modulation types are designed and transmitted by up-conversion of USRP2(Universal Software Radio Peripherals. The main contents of this paper are as follows: 1. On the basis of user-defined code source sequence, the generation technology of pseudorandom sequence code source is studied. Different pseudorandom sequence code source selection (PN9 / PN13 / PN25 et al. 2) is provided. Based on the principle of I / Q modulation, several conventional digital modulation formats, such as MASKN MFSKK MPSKN MQAM and so on, are analyzed and studied. The corresponding constellation mapping relationship between source information and baseband signal is established. The modulation output of baseband signal in multiary modulation mode is realized, and the artificial superposition channel noise is realized. The key digital shaping filtering technology in baseband signal generation is studied by adding I / Q distortion. The shaping filter mainly reduces the inter-symbol interference in the baseband signal transmission process and improves the utilization ratio of the spectrum. In this paper, the raised cosine filter and FIR filter are directly used in the design of LabVIEW to build the baseband signal shaping filter, and the shaping effect of the filter is simulated by MATLAB. Function verification and signal quality test are carried out to verify the feasibility of the design. Through the final test and comparison, the digital modulation baseband signal based on software radio can meet the needs of the signal with various modulation formats, such as ASK / FSK / PSKN QAM, etc. The highest sampling rate can reach 20 Ms / s and the highest symbol rate can reach 25 MHz. The analysis of signal EVM and MER shows that the value of EVM is less than 6 and the design meets the requirements.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TM935

【參考文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 王松濤;基于軟件無線電的數(shù)字調(diào)制解調(diào)技術(shù)的研究與實(shí)現(xiàn)[D];湖南大學(xué);2007年

，

本文編號(hào)：1868770