1bit versus 2bit
Experiment d0608 $06OCT04XA/SA was recorded in a 2 bit mode. It was correlated
two times, the first time with 2 bits per sample and the second time with
1 bit per sample (the 2nd bit of each sample was dropped).
Two pairs databases were created: $06OCT04XA/$06OCT04SA with 2bit mode
and $06OCT04X1/$06OCT04S1 with 1 bit data. The delay transfer mode was used
for investigation of influence of 1bit/2bit recording mode on EOP and site
coordinate estimates. First, both pairs of databases were analyzed
independently. Group delays, delay errors and suppression status of the
1-bit database was exported into an external file. The 2-bit database were
processed in two modes: 1) in normal mode; 2) in 1-bit emulation mode.
In that mode 1-bit delays were exported and they replaced 2-bit delays.
If the observation was suppress in either 1-bit or 2-bit mode, it was
suppressed in both the emulation mode and in the normal mode. Other solution
configuration, parameterization and weights, were kept identical. The number
of used observations was the same. The only difference between solutions
of the 2-bit database in normal mode and the 2-bit database in the 1-bit
emulation is that in the latter mode group delays were borrowed from the 1-bit
database.
Two pairs of solutions were made: EOP were estimated in the first pair
of solutions, and site positions were estimated in the another pair of
solutions.
- Spool file of the EOP solution in 1-bit
emulation mode;
- Spool file of the EOP solution in 2-bit
normal mode;
- Spool file of the site position solution in 1-bit
emulation mode;
- Spool file of the site position solution in 2-bit
normal mode;
Differences in EOP in two solutions are very small:
| X pole | 0.024 nrad |
| Y pole | 0.134 nrad |
| UT1 angle | 0.072 nrad |
| Nutation Δψ sin ε0 | 0.023 nrad |
| Nutation Δε | 0.033 nrad |
Maximum difference in baseline lengths is 0.7mm.
Differences in group delays ;
Differences in fringe phases.
Statistics of X-band group delay differences:
| Nobs: 187 | KOKEE /NYALES20 | χ2/ndg = 0.947 |
| Nobs: 124 | KOKEE /ONSALA60 | χ2/ndg = 0.855 |
| Nobs: 202 | KOKEE /WESTFORD | χ2/ndg = 0.681 |
| Nobs: 133 | KOKEE /WETTZELL | χ2/ndg = 0.803 |
| Nobs: 356 | NYALES20/ONSALA60 | χ2/ndg = 1.166 |
| Nobs: 291 | NYALES20/WESTFORD | χ2/ndg = 0.831 |
| Nobs: 337 | NYALES20/WETTZELL | χ2/ndg = 0.822 |
| Nobs: 255 | ONSALA60/WESTFORD | χ2/ndg = 0.838 |
| Nobs: 348 | ONSALA60/WETTZELL | χ2/ndg = 1.934 |
| Nobs: 242 | WESTFORD/WETTZELL | χ2/ndg = 0.685 |
Statistics of S-band group delay differences:
| Nobs: 187 | KOKEE /NYALES20 | χ2/ndg = 0.738 |
| Nobs: 124 | KOKEE /ONSALA60 | χ2/ndg = 0.818 |
| Nobs: 202 | KOKEE /WESTFORD | χ2/ndg = 0.849 |
| Nobs: 133 | KOKEE /WETTZELL | χ2/ndg = 0.789 |
| Nobs: 356 | NYALES20/ONSALA60 | χ2/ndg = 0.729 |
| Nobs: 291 | NYALES20/WESTFORD | χ2/ndg = 0.789 |
| Nobs: 337 | NYALES20/WETTZELL | χ2/ndg = 0.772 |
| Nobs: 255 | ONSALA60/WESTFORD | χ2/ndg = 0.781 |
| Nobs: 348 | ONSALA60/WETTZELL | χ2/ndg = 0.818 |
| Nobs: 242 | WESTFORD/WETTZELL | χ2/ndg = 0.627 |
Statistics of X-band phase delay differences
| Nobs: 187 | KOKEE /NYALES20 | χ2/ndg = 2.758 |
| Nobs: 124 | KOKEE /ONSALA60 | χ2/ndg = 5.995 |
| Nobs: 202 | KOKEE /WESTFORD | χ2/ndg = 2.398 |
| Nobs: 133 | KOKEE /WETTZELL | χ2/ndg = 3.131 |
| Nobs: 356 | NYALES20/ONSALA60 | χ2/ndg = 5.592 |
| Nobs: 291 | NYALES20/WESTFORD | χ2/ndg = 2.174 |
| Nobs: 337 | NYALES20/WETTZELL | χ2/ndg = 3.377 |
| Nobs: 255 | ONSALA60/WESTFORD | χ2/ndg = 3.395 |
| Nobs: 348 | ONSALA60/WETTZELL | χ2/ndg = 12.99 |
| Nobs: 242 | WESTFORD/WETTZELL | χ2/ndg = 2.836 |
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This page was prepared by Leonid Petrov
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23-JAN-2007 18:38:23
