Development of DFMC SBAS Prototype System using L1 and L5 Band Signals of GPS, Galileo, and QZSS

Abstract

Recently, next-generation standards of Satellite-based augmentation system (SBAS) have been discussed. The new SBAS augments L1 and L5 band signals of multi-constellation GNSSs. Therefore, it is called as DFMC (dual-frequency, multiconstellation) SBAS. Authors have developed DFMC SBAS prototype system. Previously on author’s research, the prototype system has augmented L1-C/A and L2P signals of GPS and GLONASS satellites. Because, the number of satellites broadcasting L5 signal (L5 satellite) was not enough. However, the L5 satellites are recently increased. Especially Galileo satellites are increased. Then, in this paper, it is described that a developed DFMC SBAS prototype system using L1 and L5 signals of GPS, Galileo, and QZSS satellites. QZSS is used as supporting GPS satellites, since the number of GPS L5 satellites is not enough yet. As the results, the developed prototype system works effectively at whole of Japan area in post-analysis. 95% positioning errors and protection levels are 0.78 m and 6.74 m in horizontal, and 1.54 m and 13.14 m in vertical respectively. The performance of the prototype system is capable of LPV-200 procedure high-frequently (availability is 99.998%). In real-time analysis (actual broadcasting test via QZSS), positioning accuracies are equal to the results of the post-analysis (95% positioning errors are 0.82 m in horizontal, and 1.16 m in vertical.). However, protection levels are worse (95% protection levels are 15.90 m in horizontal, and 25.24 m in vertical.). It can be caused by a communication failure between prototype system and ground monitoring stations. Thus, prototype system needs to improve real-time mode.