Page 138 - 卫星导航2021年第1-2合期

Liu et al. Satell Navig (2021) 2:6 Page 5 of 17

a b

c d

Fig. 1 Sky plot and availability of BDS-3 and BDS-2 satellites at MGEX station WUH2 in Wuhan on June 21, 2020

the frequency of the B1I/B3I observations; P and φ illus- Data collection
trate the code and phase observations in meters; ρ Te BDS-3/BDS-2 data collected from the static experi-
denotes the geometric distance between the receiver and ments at the Wuhan University campus were used.
satellite; represents the wavelength, while N is the inte- In the static experiments, a pair of geodetic iGMAS
ger ambiguity in cycles; e and ε denote the observation receivers (Zhang et al. 2017), a pair of Trimble Alloy
noise in code and phase, respectively; receivers (frmware version 6.05), and two Trim-
B∗ 1 B 1 ∗ ble Zephyr Geodetic 2 antennas were employed. Te
δ br,f = δ B∗ + N br,f is the reorganized phase DISB
br,f
parameter that are formed by combining the double-dif- antennas were located on the roof of our department
ferenced ambiguity between reference satellites of BDS-2 (School of Geodesy and Geomatics (SGG), Wuhan Uni-
and BDS-3 ( N 1 B 1 ∗ ) with the original phase DISB parame- versity). Te confguration of the receivers and anten-
br,f nas at the SGG stations is shown in Fig. 2. Meanwhile,
ter ( δ B∗ ); d B∗ is the code DISB parameter.
br,f br,f
raw BDS-2/BDS-3 data collected at the MGEX station
WUH2 (equipped with Javad TRE_3 receiver (frmware