本文選題：GNSS　切入點：PPP　出處：《東南大學(xué)》2016年博士論文　論文類型：學(xué)位論文

【摘要】：近年來,GNSS技術(shù)蓬勃發(fā)展,引發(fā)了導(dǎo)航定位領(lǐng)域的深刻變革,其應(yīng)用領(lǐng)域日益擴大,已廣泛服務(wù)于大地測量、空間科學(xué)、地球物理等領(lǐng)域。面對高精度、實時化GNSS應(yīng)用需求的逐步增多,相關(guān)算法的探索創(chuàng)新和系統(tǒng)研發(fā)設(shè)計將面臨新的機遇和挑戰(zhàn)。對于PPP技術(shù),初始化時間較長和受制于外部衛(wèi)星的鐘差與軌道是兩大限制實時PPP應(yīng)用的瓶頸。本文從PPP的內(nèi)部理論算法入手,針對數(shù)學(xué)模型、系統(tǒng)誤差處理等問題展開深入研究,通過結(jié)合區(qū)域CORS數(shù)據(jù)提供的增強信息,解決了PPP解算的實時性、快速性與自主性問題。主要內(nèi)容及成果包括：1.優(yōu)化了PPP觀測方程的的數(shù)學(xué)模型與方法系統(tǒng)研究了PPP的理論算法,其中包括函數(shù)模型與隨機模型。分析總結(jié)了PPP觀測方程數(shù)學(xué)模型的發(fā)展現(xiàn)狀,為提高PPP的收斂速度與定位精度,提出了改進方案：(1)提出了基于星間組合差分的PPP函數(shù)模型,既消除了部分未知參數(shù),提高了數(shù)據(jù)解算效率,同時改進了卡爾曼濾波的未知數(shù)和協(xié)因數(shù)陣初值的精度,而且避免了引入不同觀測值之間的相關(guān)性,實驗證明收斂時間較非差模型提高了30%。(2)顧及了載噪比指標(biāo)對觀測值隨機誤差的影響,在高度角隨機模型基礎(chǔ)上,引入載噪比縮放因子,更準確地反映了系統(tǒng)狀態(tài),補償了系統(tǒng)隨機誤差對未知參數(shù)估計的影響,實驗證明收斂至分米級精度所需時間明顯縮短,比高度角模型縮短了36%。2.精化了對流層延遲經(jīng)驗?zāi)Ｐ蛷臍庀髤?shù)、天頂延遲和映射函數(shù)三個方面出發(fā),改進并融合出一種新的全球?qū)α鲗友舆t改正模型SEUTROP。與原有模型相比,SEUTROP的優(yōu)勢體現(xiàn)為：(1) SEUTROP模型應(yīng)用了全球格網(wǎng)氣象參數(shù),在時間尺度和空間尺度上更能反映出對流層延遲的變化,相比標(biāo)準氣象參數(shù)的計算結(jié)果,精度提升了一個數(shù)量級。(2)與現(xiàn)有模型(以UNB3m為例)相比,SEUTROP模型在全球范圍的精度更均勻,在南半球(尤其是南極洲)區(qū)域的精度優(yōu)勢尤其明顯,在北半球冬季表現(xiàn)更好。3.建立了基于IGS產(chǎn)品的實時PPP模式用于實時PPP的IGS產(chǎn)品可分為兩類,一類基于IGU產(chǎn)品做外推預(yù)報,另一類基于Ntrip協(xié)議傳輸實時產(chǎn)品。(1)IGU預(yù)報軌道和鐘差的精度差異很大。衛(wèi)星軌道連續(xù)可導(dǎo),因此外推算法對軌道的精度損失不大,外推9小時的軌道誤差在5cm以內(nèi)；但衛(wèi)星鐘差具有離散性與隨機性,插值算法導(dǎo)致鐘差誤差普遍在10ns附近波動,不滿足實時PPP的精度需求。(2)IGS實時服務(wù)通過計算精密星歷軌道與鐘差相對廣播星歷的改正量,并基于Ntrip協(xié)議實時播發(fā)給用戶。其中精密軌道誤差在2cm至4cm范圍內(nèi)波動,優(yōu)于IGS給出的精度指標(biāo)：衛(wèi)星鐘差約0.3ns,相比IGU預(yù)報鐘差精度得到顯著提升；此外,所有的實時產(chǎn)品的數(shù)據(jù)完整性約95%,數(shù)據(jù)時延約為30s,滿足準實時PPP的應(yīng)用需求�；贗GS實時產(chǎn)品實現(xiàn)了準實時精密單點定位,定位效果與事后模式相當(dāng)。4.完善了區(qū)域CORS增強PPP的理論和應(yīng)用從理論推導(dǎo)和實驗分析兩方面驗證了區(qū)域CORS反演定位增強信息的可行性,完善了區(qū)域CORS的服務(wù)體系,充分發(fā)揮了區(qū)域CORS的潛在價值。反演的增強信息主要包括：(1)基于稀疏的區(qū)域CORS參考站網(wǎng),實現(xiàn)了實時衛(wèi)星鐘差的快速估計。通過固定衛(wèi)星軌道,理論上單臺地面跟蹤站即可實現(xiàn)鐘差反演,區(qū)域CORS多參考站加權(quán)的聯(lián)合估計算法增強了估鐘結(jié)果的可靠性與穩(wěn)定性。為了實時快速估計高采樣率鐘差,在星間差分估計低采樣率鐘差的基礎(chǔ)上,通過星間-歷元間二次差估計鐘差的歷元間變化,以累加的形式快速還原高采樣率衛(wèi)星鐘差,得到優(yōu)于0.2ns精度的衛(wèi)星鐘差,與IGS提供的精密鐘差的精度持平。(2)提出參考站的ZTD提取及區(qū)域建模方法。以靜態(tài)PPP的方式反演區(qū)域CORS參考站的ZTD,精度能夠達到毫米級。顧及高程對ZTD的影響,區(qū)域建模至少需要4個參考站,通過空間回歸模型內(nèi)插流動站用戶ZTD,在參考站網(wǎng)內(nèi)和周邊區(qū)域的用戶對流層建模精度可達到毫米級。(3)基于區(qū)域CORS實現(xiàn)UPD分離,進而獲得PPP模糊度固定解。在參考站以“寬巷-無電離層-窄巷”的經(jīng)典三步法計算衛(wèi)星UPD的小數(shù)部分FCBs,流動站用戶通過接收衛(wèi)星UPD信息固定衛(wèi)星模糊度,使PPP解算更穩(wěn)定。流動站通過接收區(qū)域CORS增強信息實現(xiàn)了PPP快速解算,收斂速度提高30%。5.提出了基于耦合鐘差的自主PPP算法利用本文提出的區(qū)域CORS鐘差快速估計技術(shù),以廣播星歷替代精密星歷計算衛(wèi)星位置,提出完全自主的PPP算法,并且將區(qū)域CORS的精密定位服務(wù)范圍向網(wǎng)外延伸了500km。該算法創(chuàng)新性包括：(1)從理論推導(dǎo)和實驗分析兩方面驗證了衛(wèi)星軌道誤差和衛(wèi)星鐘差的耦合關(guān)系,兩者可作為統(tǒng)一參數(shù)進行估計,區(qū)域CORS網(wǎng)內(nèi)參考站的實驗表明耦合估計對定位誤差方程OMC向量的影響在毫米級；(2)傳統(tǒng)CORS提供的定位服務(wù)局限于參考站覆蓋范圍之內(nèi),對于流動站跨網(wǎng)元連續(xù)作業(yè)以及超出覆蓋區(qū)域(如近海區(qū)域)的解算較困難。基于廣播星歷的實時PPP技術(shù)不但實現(xiàn)了解算數(shù)據(jù)完全自主提供,而且對于網(wǎng)內(nèi)、網(wǎng)外測站的點位精度分別提高了38.8%和36.1%,收斂速度則分別提高了61.4和65.9%。在全球化PPP服務(wù)實現(xiàn)之前,該算法可作為一種替代方案實現(xiàn)了區(qū)域定位服務(wù)。(3)在缺少BDS精密星歷的情況下,率先實現(xiàn)了基于BDS的PPP,單天解平面定位精度約lcm,與基于GPS的PPP結(jié)果一致；在高程方向上精度約10-20cm,精度較差的主要原因在于衛(wèi)星與接收機的天線參數(shù)不明確。
[Abstract]:In recent years, rapid development of GNSS technology, led to profound changes in the field of navigation and positioning, its application field is expanding, and has been widely used in geodesy, space science, earth physics and other fields. In the face of high precision, real-time GNSS application needs to increase gradually, research and design exploration innovation and system related algorithms will face new the opportunities and challenges. As for the PPP, initialization time is too long and subject to the external clock and satellite orbit is two limits of real-time PPP applications bottleneck. This article from the internal theory of PPP algorithm, according to the mathematical model, studies the system error handling and other issues, through enhanced information combined with regional CORS data. To solve the real-time computation of PPP, fast and independent problems. The main contents and results are as follows: 1. optimization of the PPP observation equation mathematical model and method of the system of the theory of PPP The algorithm, which includes function model and stochastic model. Analyzed and summarized the development situation of PPP observation equation mathematical model, in order to improve the convergence speed and the precision of PPP, put forward the improvement scheme: (1) the inter satellite combination difference model based on PPP function, which eliminates part of unknown parameters, improve the efficiency of the data calculation, we also improved Calman filter of unknowns and the coordinated factor matrix initial accuracy, but also avoid introducing different correlation between the observations and the experiments show that the convergence time is non difference model improved by 30%. (2) takes into account the effect of random error of carrier to noise ratio index of observation, in the high angle based on stochastic model introduction, CNR zoom factor, more accurately reflects the state of the system, the system compensation effect of random errors of unknown parameter estimation, the experiments show that the convergence to decimeter level precision were shortened and high Angle model shortens 36%.2. refinement of the tropospheric delay experience model from three aspects of meteorological parameters, zenith delay and mapping function of improvement and integration of a new global tropospheric delay correction model of SEUTROP. compared with the original model, the advantages of SEUTROP are: (1) SEUTROP model is applied to the global grid more meteorological parameters. Can reflect the change of the tropospheric delay in the time scale and spatial scale, the calculation results compared to standard meteorological parameters, improve the accuracy of an order of magnitude. (2) with the existing model (such as UNB3m) compared to the SEUTROP model is more uniform in the global scope of the accuracy in the Southern hemisphere (especially Antarctica) precision regional advantage is particularly evident in the northern hemisphere winter, better.3. established a real-time PPP model based on IGS for real-time PPP IGS products can be divided into two categories, one kind of extrapolation forecast based on IGU products And another kind of transmission based on Ntrip protocol in real-time products. (1) the difference of IGU forecast accuracy of orbit and clock greatly. The satellite orbit continuously differentiable, so extrapolation method to track the little loss of accuracy, extrapolation of 9 hours in orbit error is less than 5cm; but the satellite clock error is discrete and stochastic interpolation. The algorithm leads to clock in the vicinity of 10ns common error fluctuations, does not meet the accuracy requirement of real-time PPP. (2) IGS real time service by calculating the precise ephemeris orbit and clock error correction of the broadcast ephemeris, and based on the Ntrip protocol and real-time broadcasting to the user. The precise track error in the range of 2cm to 4cm range, precision index better than IGS given: satellite clock error is about 0.3ns, compared to the IGU prediction of clock precision has been significantly improved; in addition, the integrity of the data real-time all products of about 95%, the time delay of the data is about 30s, meet the application requirements. The quasi real time PPP based on IGS Real time products can realize quasi real time precise point positioning, positioning effect and improve the regional.4. model after CORS from theoretical derivation and experimental analysis verify the two aspects of regional CORS enhanced the feasibility of information inversion theory and application of PPP increased, improve the regional CORS service system, give full play to the potential value of regional CORS the enhancement of information. Inversion mainly includes: (1) regional reference station network based on sparse CORS, to achieve a rapid estimation of real-time satellite clock error. By fixing the satellite orbit, the theory of single ground tracking station clock error inversion can be CORS, the regional joint estimation algorithm of multi reference station weighted enhanced the reliability and stability. The clock. In order to real-time estimate of high sampling rate in the inter satellite clock error, differential estimation of low sampling rate based on the clock, through inter satellite - epoch two time difference estimation clock epoch In the form of rapid change, cumulative reduction of high sampling rate is better than the accuracy of 0.2ns satellite clock error, satellite clock error, flat precision clock and IGS provide poor accuracy. (2) proposed ZTD extraction and modeling method of regional reference station. In static PPP inversion region CORS reference station ZTD, accuracy at millimeter level. Take into account the impact of elevation on ZTD, regional modeling requires at least 4 reference stations, the spatial regression model interpolation in the mobile station user ZTD, user modeling precision reference station network in the troposphere and the surrounding region can reach millimeter level. (3) the CORS UPD region and PPP separation based on Fuzzy the degree of fixed solution. The classic three step in the reference station to "wide lane - - lane ionosphere free" satellite UPD calculation of the fractional part of FCBs, the mobile station user by receiving satellite information UPD fixed satellite ambiguity, the PPP solution is more stable. The flow through the grounding station Collect information to achieve PPP CORS enhanced regional fast calculation, increases the rate of convergence 30%.5. proposed PPP algorithm independent coupling clock error using the proposed region CORS clock estimation technique based on broadcast ephemeris to replace the precise ephemeris calculation of satellite position, put forward the PPP algorithm completely independent, and range of precision positioning service area CORS to extend the network innovation 500km. this algorithm includes: (1) from the theoretical and experimental analysis of two aspects to verify the coupling relationship between satellite orbit error and satellite clock error, both of them can be used as a unified parameter estimation, regional CORS network reference station experiments show that the coupling estimation of positioning error vector in equation OMC mm level; (2) the traditional positioning service provided by CORS limited to reference station coverage, for the mobile station across the ne continuous operation and beyond the coverage area (such as near the sea area) The solution is difficult. The technology of real-time PPP broadcast ephemeris is not only to achieve a completely independent data based, but also for the network, network tracking station point accuracy are improved by 38.8% and 36.1%, the convergence rate was increased by 61.4 and 65.9%. in the global PPP service before, this algorithm can be used as a the alternative to achieve regional positioning service. (3) in the absence of BDS precise ephemeris case, first to realize the BDS PPP based on single day solution plane positioning accuracy is about LCM, and based on the results of GPS PPP; in the elevation direction accuracy is about 10-20cm, the main reason lies in the poor precision of satellite and receiver antenna parameters is not clear.

【學(xué)位授予單位】：東南大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：P228.4

【相似文獻】

相關(guān)期刊論文 前10條

1 馬云飛;張柯楠;張福林;蘇占新;蘇赫;;關(guān)于CORS系統(tǒng)異構(gòu)問題的分析研究[J];城市勘測;2008年06期

2 趙小陽;孫穎;王天應(yīng);;CORS系統(tǒng)應(yīng)用規(guī)范及工程實例研究[J];科技資訊;2009年01期

3 張海瑞;陳西強;;CORS系統(tǒng)的技術(shù)特點及應(yīng)用現(xiàn)狀與展望[J];硅谷;2010年01期

4 嚴津;朱麗強;陳中新;;基于網(wǎng)絡(luò)異構(gòu)的CORS系統(tǒng)安全性探索研究[J];城市勘測;2010年01期

5 汪偉;史廷玉;張志全;;CORS系統(tǒng)的應(yīng)用發(fā)展及展望[J];城市勘測;2010年03期

6 薛崢;宋玉兵;;CORS系統(tǒng)網(wǎng)絡(luò)安全策略[J];現(xiàn)代測繪;2010年05期

7 張林科;范云峰;鮑金紅;;CORS信號在測量工作的應(yīng)用[J];中國城市經(jīng)濟;2010年10期

8 張振勇;王剛;;CORS系統(tǒng)建設(shè)經(jīng)驗談[J];中國科技信息;2011年03期

9 趙永亮;;淺談CORS系統(tǒng)的應(yīng)用與發(fā)展[J];中小企業(yè)管理與科技(上旬刊);2011年04期

10 畢紅衛(wèi);白海斌;魏亞龍;;CORS在華能伊敏露天礦數(shù)字化中的應(yīng)用[J];露天采礦技術(shù);2011年02期

相關(guān)會議論文 前10條

1 嚴津;朱麗強;陳中新;;基于網(wǎng)絡(luò)異構(gòu)的CORS系統(tǒng)安全性探索研究[A];華東六省一市測繪學(xué)會第十一次學(xué)術(shù)交流會論文集[C];2009年

2 李榮杰;李鴿;;測量工作中CORS技術(shù)的應(yīng)用[A];創(chuàng)新發(fā)展——河南省第五屆學(xué)術(shù)年會論文選集[C];2009年

3 陽力;劉文建;李土旺;;關(guān)于CORS并網(wǎng)的幾個問題[A];全國測繪科技信息網(wǎng)中南分網(wǎng)第二十四次學(xué)術(shù)信息交流會論文集[C];2010年

4 陳文波;盧儉;;對玉林市CORS系統(tǒng)布設(shè)方案的探討與分析[A];全國測繪科技信息網(wǎng)中南分網(wǎng)第二十四次學(xué)術(shù)信息交流會論文集[C];2010年

5 陽力;劉文建;李土旺;;關(guān)于CORS并網(wǎng)的幾個問題[A];廣東省測繪學(xué)會第九次會員代表大會暨學(xué)術(shù)交流會論文集[C];2010年

6 廖永生;鐘承志;;CORS應(yīng)用主要問題和應(yīng)用潛力挖掘分析[A];全國測繪科技信息網(wǎng)中南分網(wǎng)第二十一次學(xué)術(shù)信息交流會論文集[C];2007年

7 蘇占新;蘇赫;馬云飛;;關(guān)于不同級別CORS系統(tǒng)互操作問題的分析研究[A];吉林省測繪學(xué)會2008年學(xué)術(shù)年會論文集（下）[C];2008年

8 劉曦燦;武豐雷;劉成寶;;CORS系統(tǒng)雷電防護設(shè)計研究[A];華東六省一市測繪學(xué)會第十一次學(xué)術(shù)交流會論文集[C];2009年

9 周慶沖;;利用CORS實現(xiàn)海事測量定位的研究[A];中國航海學(xué)會航標(biāo)專業(yè)委員會測繪學(xué)組學(xué)術(shù)研討會學(xué)術(shù)交流論文集[C];2009年

10 李海洋;王丹;黃吉來;;CORS在城市地籍測量中的應(yīng)用[A];2010全國“三下”采煤與土地復(fù)墾學(xué)術(shù)會議論文集[C];2010年

相關(guān)重要報紙文章 前10條

1 范俊R肌±璋亓，

本文編號：1592880