LEO仿真进行SPP，定位精度出现跳动

#LEO仿真进行SPP精度出现规律性跳动

这是低轨伪距仿真的代码，各个误差模型按照SPP的设置
obs(1,3)=rho+recclk-satclkCLIGHT+ionalpha(satinfo(2),1)+trop+earthrotat-rel;

SPP定位误差呈现一定的规律性
现在的情况是earthrotat dts rel trop ion这几项用SPP最小二乘最后一次迭代算出来的参数和仿真用的相差很小，基本一样，卫星位置也基本一样（相差几毫米），但是有的历元求出来的rho（卫地距）和仿真对应的值差2个厘米，导致被接收机钟差吸收，接收机钟差变成2个厘米，实际仿真是0，我的理解是最小二乘没有收敛到最佳位置就停止迭代了

这是SPP最小二乘最后一次迭代

3 2017/09/01 00:00:59.989848 sat= 196 rs= -1024155.572   4879810.596   5989521.081 dts=     299.452 var=  0.000 svh=00
3 2017/09/01 00:00:59.993886 sat= 197 rs= -2711679.698   6742377.522   2826729.764 dts=     299.381 var=  0.000 svh=00
3 2017/09/01 00:00:59.990331 sat= 208 rs= -4880105.772   4304199.807   4293277.416 dts=     299.385 var=  0.000 svh=00
3 2017/09/01 00:00:59.991627 sat= 262 rs=  -571562.786   6385367.875   4435197.547 dts=     300.197 var=  0.000 svh=00
3 2017/09/01 00:00:59.993686 sat= 273 rs= -3786293.836   6127229.058   2986807.327 dts=     300.206 var=  0.000 svh=00
3 2017/09/01 00:00:59.988841 sat= 274 rs= -3258054.314   3601340.521   6094964.371 dts=     300.125 var=  0.000 svh=00

3 sat=196 azel=338.1  16.4 res=        0.002 P=  3043362.560 r+earthrotat=  3043649.751 r=  3043648.292 earthrotat=        1.459 dtr= -0.023 dts=      299.452 trop=  8.521 ion=  3.761 sig=1.899 varer=0.40851 vare= 0.000 vmeas=  0.090 vion=3.107 vtrp=0.090
3 sat=197 azel=194.9  45.9 res=       -0.002 P=  1832868.627 r+earthrotat=  1833162.241 r=  1833161.803 earthrotat=        0.438 dtr= -0.023 dts=      299.381 trop=  3.351 ion=  2.440 sig=1.270 varer=0.21528 vare= 0.000 vmeas=  0.090 vion=1.308 vtrp=0.090
3 sat=208 azel= 75.2  18.6 res=        0.003 P=  2898769.459 r+earthrotat=  2899056.850 r=  2899060.404 earthrotat=       -3.554 dtr= -0.023 dts=      299.385 trop=  7.550 ion=  4.464 sig=2.200 varer=0.37221 vare= 0.000 vmeas=  0.090 vion=4.377 vtrp=0.090
3 sat=262 azel=289.9  25.7 res=        0.001 P=  2510019.125 r+earthrotat=  2510310.714 r=  2510307.869 earthrotat=        2.845 dtr= -0.023 dts=      300.197 trop=  5.548 ion=  3.083 sig=1.573 varer=0.29737 vare= 0.000 vmeas=  0.090 vion=2.088 vtrp=0.090
3 sat=273 azel=138.9  43.4 res=        0.001 P=  1892789.127 r+earthrotat=  1893083.140 r=  1893084.351 earthrotat=       -1.211 dtr= -0.023 dts=      300.206 trop=  3.507 ion=  2.708 sig=1.386 varer=0.22109 vare= 0.000 vmeas=  0.090 vion=1.610 vtrp=0.090
3 sat=274 azel= 26.8  12.2 res=       -0.006 P=  3345316.592 r+earthrotat=  3345601.264 r=  3345603.233 earthrotat=       -1.969 dtr= -0.023 dts=      300.125 trop= 11.360 ion=  4.122 sig=2.083 varer=0.51464 vare= 0.000 vmeas=  0.090 vion=3.733 vtrp=0.090

这是仿真

2017/09/01 00:01:00.00000
L28 P=3043362.560 rho+earthrotat=3043649.730 rho=3043648.271 earthrotat=  1.459 dtr=  0.000 dts=     299.452 trop=  8.520 ion=  3.761 rs= -1024155.570 4879810.593 5989521.086
L29 P=1832868.627 rho+earthrotat=1833162.214 rho=1833161.776 earthrotat=  0.438 dtr=  0.000 dts=     299.380 trop=  3.351 ion=  2.441 rs= -2711679.696 6742377.520 2826729.771
L40 P=2898769.459 rho+earthrotat=2899056.827 rho=2899060.381 earthrotat= -3.554 dtr=  0.000 dts=     299.385 trop=  7.550 ion=  4.466 rs= -4880105.768 4304199.805 4293277.422
L94 P=2510019.125 rho+earthrotat=2510310.692 rho=2510307.847 earthrotat=  2.845 dtr=  0.000 dts=     300.197 trop=  5.547 ion=  3.083 rs= -571562.786 6385367.879 4435197.541
M05 P=1892789.127 rho+earthrotat=1893083.117 rho=1893084.328 earthrotat= -1.211 dtr=  0.000 dts=     300.206 trop=  3.507 ion=  2.709 rs= -3786293.836 6127229.061 2986807.321
M06 P=3345316.592 rho+earthrotat=3345601.234 rho=3345603.203 earthrotat= -1.969 dtr=  0.000 dts=     300.125 trop= 11.360 ion=  4.123 rs= -3258054.317 3601340.527 6094964.368