本文選題：非正交多址 + 稀疏碼分多址　； 參考：《電子科技大學(xué)》2017年碩士論文

【摘要】：移動(dòng)互聯(lián)網(wǎng)和物聯(lián)網(wǎng)是未來5G的重要應(yīng)用場景。高速發(fā)展的移動(dòng)互聯(lián)網(wǎng)和物聯(lián)網(wǎng)要求移動(dòng)通信網(wǎng)絡(luò)能夠提供海量接入服務(wù)。多址接入技術(shù)是移動(dòng)通信的一種重要空口技術(shù),它能夠有效的提高移動(dòng)網(wǎng)絡(luò)用戶接入數(shù)。因此,研究和設(shè)計(jì)新的多址技術(shù)具有重大的研究價(jià)值和現(xiàn)實(shí)意義。稀疏碼分多址(SCMA)是一種新型的非正交多址技術(shù),它能夠較好的適應(yīng)5G應(yīng)用場景,因此廣泛的受到業(yè)界和學(xué)術(shù)界的關(guān)注。在5G標(biāo)準(zhǔn)尚未制定完成之前,本文以SCMA為立足點(diǎn)對5G的多址技術(shù)做出探索性研究,目的在于設(shè)計(jì)出適合5G的多址技術(shù)方案。本文主要從碼本設(shè)計(jì)準(zhǔn)則和低復(fù)雜度譯碼兩個(gè)方面對SCMA這種非正交多址技術(shù)展開研究。首先,本文重點(diǎn)分析了基于星座實(shí)部和虛部混排這種經(jīng)典的碼本設(shè)計(jì)準(zhǔn)則。然后按照碼本優(yōu)化設(shè)計(jì)的基本思路,提出了一種分配星座能量和旋轉(zhuǎn)相位的碼本設(shè)計(jì)準(zhǔn)則。仿真結(jié)果表明基于新的碼本設(shè)計(jì)準(zhǔn)則設(shè)計(jì)的碼本性能存在較大的優(yōu)勢。鑒于目前碼本設(shè)計(jì)尚無統(tǒng)一的準(zhǔn)則,因此基于分配星座能量和旋轉(zhuǎn)相位的碼本設(shè)計(jì)準(zhǔn)則是一種不錯(cuò)的碼本設(shè)計(jì)備選方案。然后,本文在研究了基于因子分解圖的迭代MPA譯碼算法基礎(chǔ)上提出了一種對數(shù)域基于因子分解子圖的迭代MPA譯碼算法。一方面,一種特殊結(jié)構(gòu)的因子分解子圖在基本MPA的基礎(chǔ)上替代普通的因子分解圖,降低了消息迭代運(yùn)算過程中功能節(jié)點(diǎn)更新消息的有效運(yùn)算。另一方面,雅可比對數(shù)近似運(yùn)算被引入消息傳遞算法,簡化了消息傳遞算法中的復(fù)雜運(yùn)算。分析和仿真表明改進(jìn)的譯碼算法以小幅度的性能損失能夠換取譯碼計(jì)算復(fù)雜度的大幅度降低。因此,改進(jìn)的譯碼算法能夠在計(jì)算復(fù)雜度和誤碼性能之間取得不錯(cuò)的折中。最后,本文根據(jù)改進(jìn)的譯碼算法提出了一種基于FPGA的SCMA譯碼器實(shí)現(xiàn)方案,并且利用Verilog語言設(shè)計(jì)了6個(gè)用戶的SCMA譯碼器。電路綜合結(jié)果表明設(shè)計(jì)的SCMA譯碼器占用芯片約17%的資源。測試結(jié)果表明SCMA譯碼器完成一次多用戶聯(lián)合迭代譯碼消耗約246個(gè)時(shí)鐘周期。同時(shí),測試誤碼率和Matlab仿真誤碼率曲線基本一致,基本滿足設(shè)計(jì)要求。
[Abstract]:Mobile Internet and Internet of things are the important application scenarios of 5 G in the future. The rapid development of mobile Internet and Internet of things requires mobile communication network to provide mass access services. Multiple access (mai) is an important empty port technology in mobile communication. It can effectively improve the number of mobile network users. Therefore, the research and design of new multiple-access technology has great research value and practical significance. Sparse Code Division multiple access (SCMA) is a new non-orthogonal multiple access technology, which can adapt to 5G applications, so it has been widely concerned by the industry and academia. Before the 5G standard has been formulated, this paper takes SCMA as the foothold to do exploratory research on 5G multiple access technology, with the aim of designing a scheme suitable for 5G multiple access technology. In this paper, the non-orthogonal multiple access (NOAA) technique of SCMA is studied from two aspects: codebook design criterion and low complexity decoding. Firstly, the classical codebook design criterion based on constellation real part and virtual part is analyzed. Then, according to the basic idea of codebook optimization design, a codebook design criterion for allocating constellation energy and rotation phase is proposed. The simulation results show that the code nature based on the new codebook design criterion has great advantages. Since there is no uniform criterion for codebook design at present, the codebook design criterion based on the allocation of constellation energy and rotation phase is a good codebook design alternative. Then, an iterative MPA decoding algorithm in logarithmic domain based on factorization subgraph is proposed based on the study of iterative MPA decoding algorithm based on factorization graph. On the one hand, a special structure factorization subgraph replaces the common factorization graph on the basis of basic MPA, which reduces the effective operation of updating message in the process of message iteration. On the other hand, Jacobian logarithmic approximation is introduced into message passing algorithm, which simplifies the complex operation in message passing algorithm. The analysis and simulation show that the improved decoding algorithm can reduce the computational complexity of decoding by a small margin. Therefore, the improved decoding algorithm can achieve a good compromise between computational complexity and error performance. Finally, according to the improved decoding algorithm, this paper proposes a FPGA based SCMA decoder implementation scheme, and uses Verilog language to design six users of SCMA decoder. The circuit synthesis results show that the designed SCMA decoder occupies about 17% of the chip resources. The test results show that it takes about 246 clock cycles for the SCMA decoder to complete a multiuser joint iterative decoding. At the same time, the test BER curve is basically the same as Matlab simulation BER curve, which basically meets the design requirements.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TN929.5

【參考文獻(xiàn)】

相關(guān)期刊論文 前9條

1 袁志鋒;曹偉;黃偉芳;田力;;MUSA:面向5G IoT的免調(diào)度高過載接入方案[J];電信網(wǎng)技術(shù);2016年11期

2 梁燕;余貝;童開蒙;;高斯信道下SCMA簡易碼本設(shè)計(jì)[J];計(jì)算機(jī)應(yīng)用研究;2017年09期

3 武漢;邵凱;莊陵;王光宇;;MUSA系統(tǒng)中一種快速多用戶檢測算法[J];電子技術(shù)應(yīng)用;2016年08期

4 黃剛;楊擁軍;;衰落信道下SCMA性能仿真研究[J];計(jì)算機(jī)應(yīng)用研究;2017年05期

5 張長青;;面向5G的非正交多址接入技術(shù)的比較[J];電信網(wǎng)技術(shù);2015年11期

6 畢奇;梁林;楊?yuàn)?陳鵬;;面向5G的非正交多址接入技術(shù)[J];電信科學(xué);2015年05期

7 袁志鋒;郁光輝;李衛(wèi)敏;;面向5G的MUSA多用戶共享接入[J];電信網(wǎng)技術(shù);2015年05期

8 李世超;;5G關(guān)鍵技術(shù)之NOMA介紹[J];電子制作;2015年04期

9 李玉霞;;干擾刪除多用戶檢測分析[J];科技信息;2009年10期

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本文編號(hào)：2021854