Comparison of VieVS and Solve UT1 results from VLBI measurements

Abstract

Comparison of different geodetic VLBI analysis software packages is highly important to ensure that they work properly. Two of the data software packages used by the geodetic VLBI community are Solve and the Vienna VLBI Software VieVS packages. In our study we investigate UT1 estimates from VieVS and Solve for both 1-hour IVS Intensives and 24-hour R1s and R4s with various configurations. We synchronized the settings of the two software packages as much as possible without extensive software changes. In this configuration the weighted mean difference of the UT1 estimates from the IVS intensives was 7.8 μs with a WRMS scatter of 7.1 μs. The weighted mean difference for the 24-h sessions was -1.7 μs with a WRMS scatter of 5.5 μs. We also investigated the effect of changing other aspects of the solution configurations. In general the resulting differences were small except for imposing a tight clock constraint which significantly worsened the solutions.

Keywords

• VLBI,IVS,UT1,Earth rotation

VLBI Ölçümlerinden elde edilen VieVS ve Solve UT1 Sonuçlarının Karşılaştırılması

Abstract

Farklı jeodezik VLBI analiz yazılım paketlerinin karşılaştırılması, bu paketlerin düzgün çalıştıklarından emin olunabilmesi için son derece önemlidir. Viyana VLBI Yazılımı VieVS ve Solve, Jeodezik VLBI topluluğu tarafından kullanılan iki farklı veri yazılım paketidir. Çalışmamızda VieVS ve Solve’dan çaşitli konfigürasyonlarla elde edilen 1 saatlik IVS yoğun ve 24 saatlik R1s ve R4s UT1 ölçüleri incelenmektedir. İki yazılım paketinin ayarları mümkün olduğunca kapsamlı yazılım değişiklikleri yapılmadan senkronize edilmiştir. Bu konfigürasyonda, yoğun IVS UT1 ölçülerinin ağırlıklı ortalama farkı 7.1 μs’lik ağırlıklı karesel ortalama WRMS yayılımı ile 7.8 μs’dir. 24 saatlik ölçülerin ağırlıklı ortalama farkı 5.5 μs’lik ağırlıklı karesel ortalama WRMS yayılımı ile -1.7 μs’dir. Ayrıca çözüm konfigürasyonlarının diğer yönlerinin değişmesinin etkileri incelenmiştir. Sonuçları önemli ölçüde kötüleştiren sıkı saat kısıtlamalarının eklenmesi dışında genellikle sonuçların farkları küçüktür.

Keywords

• VLBI,IVS,UT1,Yer dönüklüğü

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