發(fā)布時(shí)間：2018-06-30 00:34

  本文選題：北斗衛(wèi)星導(dǎo)航系統(tǒng) + 基帶處理　； 參考：《北京交通大學(xué)》2014年碩士論文

【摘要】：北斗衛(wèi)星導(dǎo)航系統(tǒng)的高速發(fā)展帶動(dòng)了衛(wèi)星導(dǎo)航產(chǎn)業(yè)的快速發(fā)展。北斗接收機(jī)是北斗衛(wèi)星導(dǎo)航系統(tǒng)的用戶終端設(shè)備,低成本、高性能的接收機(jī)是其廣泛應(yīng)用的基礎(chǔ)。北斗接收機(jī)的設(shè)計(jì)可以分為三個(gè)部分：射頻前端、基帶處理和定位解算。在這三個(gè)部分中,基帶處理的性能很大程度上決定了接收機(jī)的性能,對(duì)基帶處理的研究是開發(fā)高性能接收機(jī)的重要環(huán)節(jié)。基帶處理主要完成衛(wèi)星信號(hào)的捕獲和跟蹤,目的在于使接收機(jī)內(nèi)部產(chǎn)生的載波信號(hào)和偽碼信號(hào)與射頻前端輸出的中頻信號(hào)的載波頻率和偽碼相位保持一致。當(dāng)跟蹤進(jìn)入穩(wěn)定狀態(tài)后,可以解調(diào)出衛(wèi)星的星歷和歷書數(shù)據(jù),提取偽距觀測(cè)量和多普勒頻移值,用于定位解算部分進(jìn)行PVT(位置、速度和時(shí)間)的計(jì)算。 本文對(duì)基于FPGA的北斗接收機(jī)實(shí)現(xiàn)進(jìn)行了研究,重點(diǎn)研究了基帶處理的捕獲和跟蹤。北斗衛(wèi)星信號(hào)的捕獲是衛(wèi)星編號(hào)、載波頻率和偽碼相位的三維搜索。常用的信號(hào)捕獲方法有基于時(shí)域的串行滑動(dòng)相關(guān)捕獲法、并行頻率搜索捕獲法、并行碼相位搜索捕獲法。論文對(duì)三種不同捕獲算法的計(jì)算復(fù)雜度及捕獲時(shí)間進(jìn)行了對(duì)比分析,并選擇基于時(shí)域的串行滑動(dòng)相關(guān)捕獲法的方法設(shè)計(jì)了BD2的衛(wèi)星信號(hào)捕獲。 衛(wèi)星信號(hào)的跟蹤分為載波跟蹤和偽碼跟蹤�，F(xiàn)有跟蹤方法實(shí)現(xiàn)中,載波跟蹤通常采用COSTAS環(huán)結(jié)構(gòu),偽碼跟蹤多采用延遲鎖定環(huán)結(jié)構(gòu)。本文也采用了相同的結(jié)構(gòu)對(duì)BD2的載波跟蹤和碼跟蹤部分進(jìn)行了設(shè)計(jì)。 基帶處理部分的設(shè)計(jì),在基于Xilinx的FPGA+ARM9的硬件平臺(tái)上進(jìn)行了初步驗(yàn)證。利用VHDL語言設(shè)計(jì)了基帶相關(guān)器的核心模塊,如載波NCO模塊,碼發(fā)生器模塊和碼NCO模塊等,并用Modelsim對(duì)相關(guān)的模塊設(shè)計(jì)進(jìn)行了仿真。仿真結(jié)果表明了設(shè)計(jì)的正確性。
[Abstract]:The rapid development of Beidou satellite navigation system drives the rapid development of satellite navigation industry. Beidou receiver is the terminal equipment of Beidou satellite navigation system. The low cost and high performance receiver is the basis of its wide application. The design of Beidou receiver can be divided into three parts: RF front end, baseband processing and positioning solution. In these three parts, the performance of baseband processing determines the performance of the receiver to a large extent, and the research of baseband processing is an important part in the development of high performance receiver. The baseband processing mainly accomplishes the acquisition and tracking of satellite signals, the purpose of which is to keep the carrier frequency and pseudo-code phase of the carrier signals and pseudo-code signals generated in the receiver consistent with those of the RF front-end output intermediate frequency signals. After tracking into a stable state, the satellite ephemeris and ephemeris data can be extracted, and pseudo-range observations and Doppler frequency shifts can be extracted, which can be used to calculate the PVT (position, velocity and time) in the location solution. In this paper, the implementation of the Beidou receiver based on FPGA is studied, especially the acquisition and tracking of baseband processing. The acquisition of Beidou satellite signal is a three-dimensional search of satellite number, carrier frequency and pseudo-code phase. The commonly used signal acquisition methods include serial sliding correlation acquisition based on time domain, parallel frequency search acquisition and parallel code phase search acquisition. In this paper, the computational complexity and acquisition time of three different acquisition algorithms are compared and analyzed, and the method of serial sliding correlation acquisition based on time domain is selected to design BD2 satellite signal acquisition. Satellite signal tracking is divided into carrier tracking and pseudo code tracking. In the current implementation of tracking methods, Costas loop is usually used for carrier tracking, and delay locking loop is used for pseudo code tracking. The carrier tracking and code tracking part of BD2 is designed with the same structure. The design of baseband processing is preliminarily verified on the hardware platform of FPGA ARM9 based on Xilinx. The core modules of baseband correlator, such as carrier NCO module, code generator module and code NCO module, are designed by using VHDL language, and the related modules are simulated with Modelsim. The simulation results show that the design is correct.
【學(xué)位授予單位】：北京交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TN96.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 劉競(jìng)超;鄧中亮;;基于ARM+FPGA北斗接收機(jī)設(shè)計(jì)[J];軟件;2012年12期

2 王爾申;張淑芳;胡青;姜毅;孫曉文;;GPS接收機(jī)相關(guān)器技術(shù)研究及FPGA實(shí)現(xiàn)[J];系統(tǒng)仿真學(xué)報(bào);2008年13期

3 胡輝;袁超;吳超;高明華;;基于FPGA的GPS接收機(jī)相關(guān)器技術(shù)研究與實(shí)現(xiàn)[J];系統(tǒng)仿真學(xué)報(bào);2011年07期

4 張正p，

本文編號(hào)：2084058