Faculty of Civil Engineering, Environmental and Geodetic Sciences, Koszalin University of Technology, Śniadeckich 2, 75-453 Koszalin, Poland.
Space Research Centre, Polish Academy of Sciences, Bartycka 18A, 00-716 Warsaw, Poland.
Sensors (Basel). 2020 Nov 30;20(23):6851. doi: 10.3390/s20236851.
This paper deals with the analysis of local Love and Shida numbers (parameters and ) values of the Australian Yarragadee and Mount Stromlo satellite laser ranging (SLR) stations. The research was conducted based on data from the Medium Earth Orbit (MEO) satellites, LAGEOS-1 and LAGEOS-2, and Low Earth Orbit (LEO) satellites, STELLA and STARLETTE. Data from a 60-month time interval, from 01.01.2014 to 01.01.2019, was used. In the first research stage, the Love and Shida numbers values were determined separately from observations of each satellite; the obtained values of , exhibit a high degree of compliance, and the differences do not exceed formal error values. At this stage, we found that it was not possible to determine from the data of STELLA and STARLETTE. In the second research stage, we combined the satellite observations of MEO (LAGEOS-1+LAGEOS-2) and LEO (STELLA+STARLETTE) and redefined the , parameters. The final values were adopted, and further analyses were made based on the values obtained from the combined observations. For the Yarragadee station, local = 0.5756 ± 0.0005 and = 0.0751 ± 0.0002 values were obtained from LAGEOS-1 + LAGEOS-2 and = 0.5742 ± 0.0015 were obtained from STELLA+STARLETTE data. For the Mount Stromlo station, we obtained the local = 0.5601 ± 0.0006 and = 0.0637 ± 0.0003 values from LAGEOS-1+LAGEOS-2 and = 0.5618 ± 0.0017 from STELLA + STARLETTE. We found discrepancies between the local parameters determined for the Yarragadee and Mount Stromlo stations and the commonly used values of the , parameters averaged for the whole Earth (so-called global nominal parameters). The sequential equalization method was used for the analysis, which allowed to determine the minimum time interval necessary to obtain stable , values. It turned out to be about 50 months. Additionally, we investigated the impact of the use of local values of the Love/Shida numbers on the determination of the Yarragadee and Mount Stromlo station coordinates. We proposed to determine the stations (, , ) coordinates in International Terrestrial Reference Frame 2014 (ITRF2014) in two computational versions: using global nominal , values and local , values calculated during this research. We found that the use of the local values of the , parameters in the process of determining the stations coordinates influences the result.
本文研究了澳大利亚 Yarragadee 和 Mount Stromlo 卫星激光测距（SLR）站的本地 Love 和 Shida 数（参数 和 ）值的分析。该研究基于 Medium Earth Orbit（MEO）卫星 LAGEOS-1 和 LAGEOS-2 以及 Low Earth Orbit（LEO）卫星 STELLA 和 STARLETTE 的数据进行。使用了 60 个月的时间间隔，即 2014 年 1 月 1 日至 2019 年 1 月 1 日的数据。在第一研究阶段，从每个卫星的观测中分别确定了 Love 和 Shida 数的值；获得的 ， 值表现出高度的一致性，差异不超过正规误差值。在这一阶段，我们发现无法从 STELLA 和 STARLETTE 的数据中确定 。在第二研究阶段，我们组合了 MEO（LAGEOS-1+LAGEOS-2）和 LEO（STELLA+STARLETTE）的卫星观测结果，并重新定义了 ， 参数。采用了最终值，并根据组合观测结果进行了进一步分析。对于 Yarragadee 站，从 LAGEOS-1+LAGEOS-2 观测中得到本地 =0.5756±0.0005 和 =0.0751±0.0002 的值，从 STELLA+STARLETTE 数据中得到本地 =0.5742±0.0015 的值。对于 Mount Stromlo 站，从 LAGEOS-1+LAGEOS-2 观测中得到本地 =0.5601±0.0006 和 =0.0637±0.0003 的值，从 STELLA+STARLETTE 观测中得到本地 =0.5618±0.0017 的值。我们发现，Yarragadee 和 Mount Stromlo 站确定的本地参数与地球平均（所谓的全球标称参数）的 Love/Shida 数参数之间存在差异。我们使用了序列均衡化方法进行分析，该方法可以确定获得稳定的 Love/Shida 数参数值所需的最小时间间隔。结果表明，大约需要 50 个月。此外，我们还研究了 Love/Shida 数的本地值对 Yarragadee 和 Mount Stromlo 站坐标确定的影响。我们提出了在国际地面参考框架 2014（ITRF2014）中确定站（，，）坐标的两种计算版本：使用全球标称 Love/Shida 数参数值和本研究中计算得到的本地 Love/Shida 数参数值。我们发现，在确定站坐标的过程中使用本地 Love/Shida 数参数值会影响结果。
