First Preliminary Fast Static Ambiguity Resolution Results of Medium-Baseline with Triple-Frequency Beidou Wavebands

Abstract

Fast high precision relative Global Navigation Satellite System (GNSS) positioning is very important to various applications and ambiguity resolution is a key requirement. It has been a continuing challenge to determine and fix GNSS carrier-phase ambiguity, especially for medium-and long-distance baselines. In past research, with dual-frequency band Global Positioning System (GPS), it is almost impossible for fast ambiguity resolution of mediumand long-distance baselines mainly due to the ionospheric and tropospheric effects. With the launch of the BeiDou system, triple-frequency band GNSS observations are available for the first time. This research aims to test the ambiguity resolution performance with BeiDou triplefrequency band observations. In this research, two mathematical models are compared: zenith tropospheric delay as an unknown parameter versus corrected tropospheric delay. The ambiguity resolution performance is investigated in detail with BeiDou observations. Different distance baselines are tested: 45 km, 70 km and 100 km and the performances are investigated with different elevation cut-off angles. Also the performance with BeiDou alone and combined BeiDou and GPS are compared. Experimental results clearly show that with practical observations of triple-frequency bands, ambiguity of medium-or long-distance baselines can be fixed. The results also show that: the performance of ambiguity resolution with an elevation cutoff angle of 20°is much better than that of 15°; The performance with tropospheric effect corrected is slightly better than that with tropospheric effect as an estimated parameter; Dual-frequency band GPS observations will benefit ambiguity resolution of integrated BeiDou and GPS. K E Y WO R D S 1. BeiDou.2. Ambiguity resolution. 3. Medium-and long-distance baselines. 4. Ionosphere.5. Troposphere.

Performance analysis of triple-frequency ambiguity resolution with BeiDou observations

“…Some studies have been tried to improve the BDS AR Units are in hours. ''9'' indicates that the ambiguities are not fixed successfully during this period GPS Solut performance over medium or long baselines by adopting high elevation cutoff angles or applying tropospheric effect corrected model (Ji et al 2014). However, more efforts are still needed around this topic.…”

A New GNSS Single-Epoch Ambiguity Resolution Method Based on Triple-Frequency Signals

“…In this section, we verify the ambiguity by comparing the estimated coordinate with the accurate coordinate. The ambiguity-fix rate (AFR) [33] was applied to quantify the efficiency performance of AR with the following definition: AFR = Number of epochs with ambiguity fixed to integer Total number of epochs observed in the data sets (36)…”

A new ionosphere-free ambiguity resolution method for long-range baseline with GNSS triple-frequency signals

“…3 shows the number of visible satellites of GPS, BDS and GPS + BDS. In this study, the cutoff elevation angle was set to 15°for GPS satellites, and which was set to 20°for BDS due to the large noise of BDS observation below 20 (Ji et al,2014;Xu and Ji, 2015). For BDS, the observed satellites included BDS satellites from C01 to C14.…”