Performance Improvement of Grid Ionospheric Delay Correction Based on Multiple Constellations for Single-Frequency SBAS User

摘要

In the next few years, it is possible that GNSS users utilize four or more constellations in order to locate their position. Due to the benefits of multi-constellation concept, the research on the multi-constellation Satellite Based Augmentation System (SBAS) is being emphasized. However, the current SBAS has some limitations to support multiple constellations. The L1/L5 MOPS, which has been implemented recently, is one of the methods to overcome the problem about multi-constellation use. Nonetheless, not only GPS-only users but also multi-constellation users who have L1-only capability cannot take advantage of the benefits from multi-constellation. This paper focuses on the performance improvements of the single-frequency SBAS users who cannot receive the corrections for multiple constellations. In order to construct accurate and reliable L1-only SBAS, we need more improved ionospheric delay corrections. Therefore, we analyzed how to generate more reliable ionospheric corrections using multiple constellations. Then we examined the benefits of multi-constellation use through evaluating the performance of accuracy and availability for legacy SBAS (L1 GPS-only) users.