天文学进展
天文學進展
천문학진전
PROGRESS IN ASTRONOMY
2014年
3期
383-394
,共12页
对流层延迟%映射函数%精密单点定位%GPS
對流層延遲%映射函數%精密單點定位%GPS
대류층연지%영사함수%정밀단점정위%GPS
tropospheric propagation delay%mapping function%precise point position%GPS
介绍了GNSS 定位中常用的三种对流层映射函数NMF、GMF、VMF1和一种新的模型--GPT2，通过测站气压、天顶静力学延迟分量以及投影函数参数三个方面对这几个模型进行了比较。采用不同的模型对全球均匀分布的30个IGS测站2012年全年的GPS观测数据进行精密单点定位，分析了不同模型解算的测站坐标与对流层天顶延迟精度。分析结果表明：以实测气压为基准，VMF1模型气压误差仅为0.4%，GPT2模型相对于GPT 模型改善了约25%；以VMF1 HT模型为基准，GPT和GPT2模型天顶静力学延迟中误差约为1 cm，GPT2模型精度略优于GPT模型；以VMF1网站发布的测站VMF1模型为基准，GPT2模型的干、湿映射函数参数ah、aw 中误差约为1×10-5和5×10-5；在IGS08框架下，GMF/GPT与VMF1/GPT2模型的PPP 坐标解精度比NMF 提高了22%；两模型定位精度与ZTD 精度都明显高于NMF模型。
介紹瞭GNSS 定位中常用的三種對流層映射函數NMF、GMF、VMF1和一種新的模型--GPT2，通過測站氣壓、天頂靜力學延遲分量以及投影函數參數三箇方麵對這幾箇模型進行瞭比較。採用不同的模型對全毬均勻分佈的30箇IGS測站2012年全年的GPS觀測數據進行精密單點定位，分析瞭不同模型解算的測站坐標與對流層天頂延遲精度。分析結果錶明：以實測氣壓為基準，VMF1模型氣壓誤差僅為0.4%，GPT2模型相對于GPT 模型改善瞭約25%；以VMF1 HT模型為基準，GPT和GPT2模型天頂靜力學延遲中誤差約為1 cm，GPT2模型精度略優于GPT模型；以VMF1網站髮佈的測站VMF1模型為基準，GPT2模型的榦、濕映射函數參數ah、aw 中誤差約為1×10-5和5×10-5；在IGS08框架下，GMF/GPT與VMF1/GPT2模型的PPP 坐標解精度比NMF 提高瞭22%；兩模型定位精度與ZTD 精度都明顯高于NMF模型。
개소료GNSS 정위중상용적삼충대류층영사함수NMF、GMF、VMF1화일충신적모형--GPT2，통과측참기압、천정정역학연지분량이급투영함수삼수삼개방면대저궤개모형진행료비교。채용불동적모형대전구균균분포적30개IGS측참2012년전년적GPS관측수거진행정밀단점정위，분석료불동모형해산적측참좌표여대류층천정연지정도。분석결과표명：이실측기압위기준，VMF1모형기압오차부위0.4%，GPT2모형상대우GPT 모형개선료약25%；이VMF1 HT모형위기준，GPT화GPT2모형천정정역학연지중오차약위1 cm，GPT2모형정도략우우GPT모형；이VMF1망참발포적측참VMF1모형위기준，GPT2모형적간、습영사함수삼수ah、aw 중오차약위1×10-5화5×10-5；재IGS08광가하，GMF/GPT여VMF1/GPT2모형적PPP 좌표해정도비NMF 제고료22%；량모형정위정도여ZTD 정도도명현고우NMF모형。
Three models frequently used within the IGS for tropospheric propagation delay estimation including NMF, GMF/GPT, VMF1, and the newly-developed model GPT2 are presented in this paper. These models are compared in two scenarios: pressure, hydrostatic zenith delay and mapping function coefficients from different models were compared directly;coordinates and tropospheric parameters from the Precise Point Position (PPP) solutions based on different models using 1 year data of 30 global distributed IGS stations were compared. Results show: (1) Compared to the measured true pressure, VMF1 is the most accurate modeling more than 99.6% of pressure and the accuracy of GPT2 is improved by 25% over GPT; (2) Compared to the VMF1 HT model estimates, the RMS of hydrostatic zenith delay is 1 cm for both GPT and GPT2, and GPT2 is better than GPT;(3) Compared to the daily site VMF1 data, the RMS of mapping function coefficients ah and aw of GPT2 are 1 × 10-5 and 5 × 10-5, respectively;(4) Considering the coordinates from IGS08 frame as true values, estimated coordinates using GMF/GPT or VMF1/GPT2 have an improvement of 22%than NMF;(5) The PPP ZTD estimates using GMF/GPT and VMF1/GPT2 model are more accurate than NMF.
