【摘要】：作為時(shí)分復(fù)用技術(shù)的一種實(shí)現(xiàn)方式,準(zhǔn)正交時(shí)分復(fù)用(QOTDM)技術(shù)應(yīng)用于星上透明轉(zhuǎn)發(fā)系統(tǒng)中,具有操作簡單易行、星上處理復(fù)雜度較低等優(yōu)點(diǎn)。因此,其在衛(wèi)星通信中具有很大的應(yīng)用價(jià)值。本文主要對(duì)QOTDM技術(shù)進(jìn)行了系統(tǒng)的理論研究,并結(jié)合Ka波段衛(wèi)星通信信道的特點(diǎn),搭建了基于Ka波段通信的寬帶QOTDM信息傳輸系統(tǒng),且對(duì)該傳輸系統(tǒng)進(jìn)行了性能仿真分析及FPGA實(shí)現(xiàn)。本論文的主要工作及所取得的研究成果如下:1、對(duì)寬帶QOTDM傳輸方式進(jìn)行了詳細(xì)的理論研究。分析了采用直接交織方式的基本QOTDM信息傳輸系統(tǒng)的原理,并給出基本實(shí)現(xiàn)方法;提出了一種基于多載波調(diào)制的改進(jìn)QOTDM傳輸方法,提高了系統(tǒng)的抗多徑、抗頻率選擇性衰落的能力。2、對(duì)Ka波段GEO衛(wèi)星通信的信道特性進(jìn)行分析。建立了一個(gè)針對(duì)Ka波段GEO衛(wèi)星通信的信道仿真模型;分析了不同天氣條件對(duì)基本QOTDM信息傳輸系統(tǒng)性能的影響。仿真結(jié)果表明:包絡(luò)衰落對(duì)系統(tǒng)性能的影響比較嚴(yán)重,而由相位畸變帶來的影響相對(duì)于包絡(luò)衰落可忽略不計(jì)。3、對(duì)寬帶QOTDM傳輸系統(tǒng)的同步方法進(jìn)行研究。分析了采樣偏差對(duì)系統(tǒng)性能的影響,提出基于固定門限算法和群時(shí)延匹配濾波器組的系統(tǒng)同步方案。由性能仿真分析可得:該同步方案能夠?qū)崿F(xiàn)接收信號(hào)的精確樣點(diǎn)同步和幀同步,且保證系統(tǒng)的同步精度達(dá)到采樣間隔的5%。4、完成了基于多載波調(diào)制的寬帶QOTDM傳輸系統(tǒng)的FPGA實(shí)現(xiàn)。對(duì)整個(gè)傳輸系統(tǒng)進(jìn)行模塊化,分別對(duì)各個(gè)模塊進(jìn)行FPGA設(shè)計(jì),并對(duì)其進(jìn)行了硬件仿真分析。
[Abstract]:As a realization of time division multiplexing (TDM), Quasi-orthogonal TDM (QOTDM) technology is applied to the onboard transparent forwarding system, which has the advantages of simple operation and low onboard processing complexity. Therefore, it has great application value in satellite communication. In this paper, the theory of QOTDM technology is studied, and combining the characteristics of Ka band satellite communication channel, a broadband QOTDM information transmission system based on Ka band communication is built, and the performance simulation analysis and FPGA implementation of the system are carried out. The main work and results of this thesis are as follows: 1. The theory of broadband QOTDM transmission is studied in detail. The principle of the basic QOTDM information transmission system with direct interleaving is analyzed, and the basic realization method is given, and an improved QOTDM transmission method based on multicarrier modulation is proposed, which improves the anti-multipath of the system. Second, the channel characteristics of Ka band GEO satellite communication are analyzed. A channel simulation model for Ka band GEO satellite communication is established, and the influence of different weather conditions on the performance of the basic QOTDM information transmission system is analyzed. The simulation results show that the influence of envelope fading on system performance is serious, while the effect of phase distortion is negligible relative to envelope fading. 3. The synchronization method of broadband QOTDM transmission system is studied. The influence of sampling deviation on system performance is analyzed. A synchronization scheme based on fixed threshold algorithm and group delay matched filter bank is proposed. The simulation results show that the synchronization scheme can realize the precise sample synchronization and frame synchronization of the received signal, and ensure the synchronization accuracy of the system to reach 5.4 of the sampling interval. The FPGA implementation of the broadband QOTDM transmission system based on multi-carrier modulation is completed. The whole transmission system is modularized, each module is designed by FPGA, and the hardware simulation is carried out.
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TN927.2

【參考文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 胥鶴;Ka頻段衛(wèi)星通信系統(tǒng)的OFDM信道性能分析[D];吉林大學(xué);2013年

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本文編號(hào)：2262007