Construction of Meteorological Application System Based on National BDS Ground-based Augmentation Network and the Water Vapor Products Validation

Abstract

Abstract National BDS ground-based augmentation network (BGAN) of China is constructed with the existing GNSS observation resources of industry departments and local governments, based on the concept of joint building and sharing with sustainable development. This study provides a detailed introduction to the design, construction and operation of meteorological application system based on BGAN, and validation of its water vapor products. BDS and GPS synchronization and real-time observation of atmospheric water vapor products are achieved nationwide in China, as well as the application of multi-GNSS. Through the application of multi-GNSS data and validation of the water vapor products from year 2018 to 2020, the accuracy of precipitable water vapor (PWV) inversed with only BDS is equivalent to that with only GPS, which is a proven application internationally. The root mean square error (RMSE) between them is around 2 mm with high correlation coefficient. Based on radiosonde data, the validation is conducted on the products of BDS/PWV, GPS/PWV, and Combine/PWV, which are water vapor inversed with only BDS, only GPS and multi-GNSS of BDS + GPS respectively. The error characteristics of the three products show a consistent trend over the months. The bias is relatively small. The RMSE of the three products is 2.18–2.73 mm, and BDS/PWV was the largest, followed by GPS/PWV, and Combine/PWV is the smallest.