本文選題：高動態(tài) + 導(dǎo)航信號　； 參考：《電子科技大學(xué)》2014年碩士論文

【摘要】：GPS(全球定位系統(tǒng))是新一代衛(wèi)星導(dǎo)航定位系統(tǒng),在民用和軍事等方面有著廣泛應(yīng)用。而導(dǎo)彈、運(yùn)載火箭等載體大都是工作在高動態(tài)環(huán)境,具有較大的運(yùn)動速度和加速度,導(dǎo)航接收機(jī)所接收到的信號和本地信號之間存在較大的多普勒頻偏和偽碼延時,對信號的捕獲提出很高的技術(shù)要求。本文主要針對高動態(tài)環(huán)境下導(dǎo)航信號的捕獲展開討論,具體研究內(nèi)容如下:本文先對GPS信號的結(jié)構(gòu)特性進(jìn)行分析,在研究導(dǎo)航信號捕獲基本原理的基礎(chǔ)上建立PMF-FFT捕獲算法的數(shù)學(xué)模型。針對該算法存在的扇貝損失問題,分析和研究數(shù)據(jù)補(bǔ)零和加窗補(bǔ)償?shù)葍煞N方法,有效消除扇貝損失的影響。通過建立高動態(tài)環(huán)境下的導(dǎo)航信號數(shù)學(xué)模型,分析載波多普勒頻偏及其變化率和偽碼延時,研究偽碼延時和載波多普勒頻偏對相干輸出帶來的影響。在此基礎(chǔ)上對PMF-FFT的捕獲系統(tǒng)中各項(xiàng)參數(shù)做詳細(xì)的分析設(shè)計(jì),并提出高動態(tài)環(huán)境下基于改進(jìn)的PMF-FFT算法的捕獲方案,通過MATLAB仿真實(shí)驗(yàn)表明,此方案的捕獲性能良好�？紤]FPGA芯片內(nèi)部資源,提出硬件可實(shí)現(xiàn)的高動態(tài)捕獲方案。采用自頂而下的設(shè)計(jì)方法,將整個捕獲系統(tǒng)劃分為各個子模塊,并對其輸入激勵驗(yàn)證功能。采用改進(jìn)的匹配濾波器結(jié)構(gòu)減小芯片存儲資源消耗;加入雙D觸發(fā)器同步電路解決跨時鐘域異步問題;采用截取高位的方式對每個模塊的輸入輸出端口做最佳精度定點(diǎn)量化處理,盡量做到資源優(yōu)化的同時保證量化損失不影響捕獲性能;通過狀態(tài)機(jī)的控制將各個子模塊連成一個有機(jī)整體。最后搭建高動態(tài)捕獲測試閉環(huán)系統(tǒng)。模擬多種高動態(tài)運(yùn)動場景,測試結(jié)果表明,本文捕獲方法適用于20g的高動態(tài)環(huán)境。
[Abstract]:GPS (Global Positioning system) is a new generation of satellite navigation and positioning system, which is widely used in civil and military fields. However, most of the carriers, such as missiles and launch vehicles, work in high dynamic environments, with high velocity and acceleration, and there is a large Doppler frequency offset and pseudo-code delay between the signals received by the navigation receiver and the local signals. High technical requirements for signal acquisition are put forward. In this paper, the acquisition of navigation signals in high dynamic environment is discussed. The main contents are as follows: firstly, the structural characteristics of GPS signals are analyzed. On the basis of studying the basic principle of navigation signal acquisition, the mathematical model of PMF-FFT acquisition algorithm is established. Aiming at the scallop loss problem in this algorithm, two methods, data compensation and window compensation, are analyzed and studied to eliminate the effect of scallop loss. By establishing the mathematical model of navigation signal in high dynamic environment, the carrier Doppler frequency offset and its variation rate and pseudo code delay are analyzed, and the influence of pseudo code delay and carrier Doppler frequency offset on coherent output is studied. On this basis, the parameters of PMF-FFT capture system are analyzed and designed in detail, and the capture scheme based on improved PMF-FFT algorithm in high dynamic environment is proposed. The simulation results of MATLAB show that the capture performance of this scheme is good. Considering the internal resources of FPGA chip, a high dynamic capture scheme is proposed. Using the top-down design method, the whole capture system is divided into each sub-module, and the input excitation verification function is given. The improved matched filter structure is adopted to reduce the memory consumption of the chip and the synchronous circuit of double D flip-flop is added to solve the asynchronous problem across the clock domain. The input and output ports of each module are processed with the best precision fixed-point quantization in the way of intercepting the high position, so as to optimize the resource and ensure that the quantization loss does not affect the capture performance. Each sub-module is connected into an organic whole by the control of the state machine. Finally, a high dynamic capture test closed loop system is built. The simulation results show that the capture method is suitable for 20g high dynamic environment.
【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】：2014
【分類號】：TN967.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 柳春;甘泉;;基于FPGA的雷達(dá)信號源設(shè)計(jì)[J];電子技術(shù)應(yīng)用;2013年11期

相關(guān)博士學(xué)位論文 前1條

1 左啟耀;高動態(tài)GPS信號跟蹤算法研究[D];中國科學(xué)院研究生院（空間科學(xué)與應(yīng)用研究中心）;2008年

相關(guān)碩士學(xué)位論文 前1條

1 吳華兵;GNSS P碼直捕算法研究與實(shí)現(xiàn)[D];中國科學(xué)院研究生院（國家授時中心）;2011年

，

本文編號：1824151