Format for 2SOPS GPS Raw Data File (.2sops)
This is a binary file. All multibyte fields are in little endian (least significant byte first) order. Double precision values are IEEE floating point.
Data comes in 6-second chunks from the different Monitor stations. Each record contains data for one of these 6-second chunks. There are 4 pseudo-ranges per record; one pseudo-range per each of 4 successive Z-counts where 1 Z-Count is 1.5 seconds. The first data item - Z-Counts since GPS epoch is the Time of Transmission from the GPS SV. That time corresponds to the last (4th) pseudo-range in the set of 4.
Record Description:
| Item | Size (bytes) | Type | Description | Units |
|---|---|---|---|---|
| 1 | 8 | Double | Time of transmission (t) from GPS SV corresponding to the last (4th) pseudo-range in the set of 4. | Z-Counts since GPS Epoch |
| 2 | 1 | Unsigned integer | PRN | - |
| 3 | 1 | Unsigned integer | Monitor Station ID (MSID) | - |
| 4 | 1 | Unsigned integer | 1 = L1, 2 = L2 | |
| 5 | 1 | Unsigned integer | Antenna id. = 0 If no antenna id is supplied | - |
| 6 | 4 | Unsigned integer | Unused | - |
| 7 | 8 | Double | Pseudo-range 1 | meters |
| 8 | 8 | Double | Pseudo-range 2 | meters |
| 9 | 8 | Double | Pseudo-range 3 | meters |
| 10 | 8 | Double | Pseudo-range 4 | meters |