Single-Differenced Ambiguity Resolution for Orbit Determination of the Haiyang-2B

Abstract

In ambiguity resolution, the Hatch-Melbourne-Wübbena code and carrier phase combination is usually used to fix the wide-lane (WL) ambiguity, and thus, the quality of the code observations directly affects the fixing success rate, especially when there are some kind of serious bias errors. Unfortunately, we found that the P1 code multipath (MP) errors of the Haiyang-2B calculated using the MP combination formula rapidly increases from sub-meter to several meters at elevation less than 40°. These rapid variations lead to biases in the fixed WL ambiguities. In this article, we create a static correction map on a grid with 5°x 5°r esolution. Using this correction map, we reduced the root mean square of the P1 code bias errors from 1.04 to 0.47 m, which corresponds to an improvement of 54.8%. By comparing the different precise orbit determination solutions, we found that the ambiguity resolution significantly reduced the satellite laser ranging (SLR) residuals from 1.63 to 1.31 cm with an average improvement of 19.6%. However, because of the code errors, the ambiguity fixing rate of the P1 ambiguity-fixed solutions was much lower than that of the C1 solutions. By modeling this static correction, the impact of these errors was effectively reduced. The ambiguity fixing rate for the P1 solutions was improved by 15.6% and a 1-3 mm reduction in the SLR residuals was small but noticeable.Index Terms-Ambiguity resolution, code bias, Haiyang-2B, onboard global positioning system (GPS), orbit determination. I. INTRODUCTIONT HE Haiyang-2B microwave remote sensing satellite was launched using a CZ-4B rocket on October 25, 2018. In order to obtain high-precision orbit information, the satellite uses an onboard dual-frequency global positioning system (GPS) receiver as its key tracking system. This instrument was independently developed by the Space Star Technology Co., Ltd. and was used on several Chinese satellites, including ZY-3,

Precise orbit determination of Haiyang-2D using onboard BDS-3 B1C/B2a observations with ambiguity resolution

“…Haiyang-2D is a scientific satellite mission for investigating dynamic marine environments and sea surface altimetry, following the previous missions (Gao et al, 2014;Peng et al, 2021;Wang et al, 2022a). The primary payload consists of a dual-frequency radar altimeter and an advanced microwave radiometer.…”