||
目前MGEX项目在大陆地区拥有北斗观测数据的台站有五个:URUM、LHAZ、JFNG、WUH2、KMNM;
上一篇博文采用LHAZ、URUM解算北斗三号,在最后一步SOLVE最小二乘求解时出现如下错误:
FATAL :200427:2031:29.0 SOLVE/lcloos: Inversion error in LCNORM(2)
查看gamit/solve/lcloos.f文件发现是调用lcnorm函数出现错误
打开lcnorm.f文件,发现如下:
IJOB=2,表示解LC模式法方程,那么说很可能就是解算的时候法方程矩阵秩亏,导致无解出错;
仔细查看原始观测数据,发现了问题所在:
LHAZ的观测文件中北斗数据类型:
C 8 C2I C7I D2I D7I L2I L7I S2I S7I SYS / # / OBS TYPES
URUM的观测文件中北斗数据类型:
C 26 C1X C2I C5X C6I C7I C7Z D1X D2I D5X D6I D7I D7Z D8X SYS / # / OBS TYPES
L1X L2I L5X L6I L7I L7Z L8X S1X S2I S5X S6I S7I S7Z SYS / # / OBS TYPES
梳理一下,只看伪距和载波,多普勒和信号强度先不管,对比下面RINEX3.04北斗系统观测码发现:
LHAZ C2I C7I L2I L7I 只有北斗二代信号
URUM C1X C2I C5X C6I C7I C7Z L1X L2I L5X L6I L7I L7Z L8X 北斗二代和三代信号均有
为了验证是观测数据问题,下载了WUH2测站数据,其包含的北斗观测数据类型:
C 28 C1X C2I C5X C6I C7I C7Z C8X D1X D2I D5X D6I D7I D7Z SYS / # / OBS TYPES
D8X L1X L2I L5X L6I L7I L7Z L8X S1X S2I S5X S6I S7I SYS / # / OBS TYPES
和URUM站一样,两个都是JAVAD TRE_3接收机,同时支持北斗二代和三代观测值;
所以,换成GAMIT10.71解算URUM和WUH2测站北斗三号观测数据,过程和以前解算一样,注意包含多阶电离层改正模型:
$ sh_gamit -expt bdxt -d 2020 090 -orbit gfzm -gnss C -noftp -ion
解算结果如下:
Input options -expt bdxt -d 2020 090 -orbit gfzm -gnss C -noftp -ion
Processing 2020 090 GPS week 2099 1 Using node: DESKTOP-N0UE137 Started at: 20_05_01_14:20:43
Processing directory: /home/chaoshu/bdxt/090C
Disk Usage: 207766 Free 34407.4 Mbyte. Used 86%
Number of stations used 2 Total xfiles 2
Postfit RMS rms, total and by satellite
RMS IT Site All 02 06 07 08 09 10 11 12 13 14 16 18 19 20 21 22 23 24 25 26 27 28 29 30 32 33 34 35
RMS 20 ALL 5.7 110 41 42 52 52 55 63 73 58 65 43 0 61 40 48 55 47 55 50 63 64 72 53 45 54 50 61 53
Best and Worst two sites:
RMS 20 ALL 5.7 110 41 42 52 52 55 63 73 58 65 43 0 61 40 48 55 47 55 50 63 64 72 53 45 54 50 61 53
RMS 20 URUM 5.7 11 4 4 5 5 6 6 7 6 6 4 0 6 4 5 6 5 6 5 6 6 7 5 5 5 5 6 5
RMS 20 URUM 5.7 11 4 4 5 5 6 6 7 6 6 4 0 6 4 5 6 5 6 5 6 6 7 5 5 5 5 6 5
RMS 20 WUH2 5.7 11 4 4 5 5 6 6 7 6 7 4 0 6 4 5 6 5 5 5 6 6 7 5 5 5 5 6 5
Double difference statistics
Prefit nrms: 0.49925E+00 Postfit nrms: 0.22393E+00
Prefit nrms: 0.49833E+00 Postfit nrms: 0.23324E+00
Prefit nrms: 0.49925E+00 Postfit nrms: 0.22393E+00
Prefit nrms: 0.49833E+00 Postfit nrms: 0.23324E+00
Number of double differences: 4939
Phase ambiguities (Total WL-fixed NL-fixed): 26 23 18 AUTCLN (Total Expected) 26 26
Phase ambiguities WL fixed 88.5% NL fixed 69.2%
...
Processing 2020 090 GPS week 2099 1 Using node: DESKTOP-N0UE137 Finished at: 20_05_01_14:55:22
资料传送:
北斗三号观测数据下载地址
可以接收北斗三号新信号的MGEX观测站
ftp://igs.ign.fr/pub/igs/data/campaign/mgex/daily/rinex3
POTS SGOC SUTM ULAB URUM WIND WUH2
北斗三号卫星精密星历
武大WUM:ftp://igs.ign.fr/pub/igs/products/mgex
GFZ GBM:ftp://ftp.gfz-potsdam.de/pub/GNSS/products/mgex
Archiver|手机版|科学网 ( 京ICP备07017567号-12 )
GMT+8, 2024-9-2 06:13
Powered by ScienceNet.cn
Copyright © 2007- 中国科学报社