Format for Navigation Solution Tracking Data File (.navsol)
Each line contains a single record. Each record begins with the following standard information (space-delimited):
| Column | Description |
|---|---|
| ReceiverID | Identifier of GPS receiver (integer) |
| Year | Four-digit year (integer) |
| Month | Two-digit month, e.g., Jan = 01 (integer) |
| Day | Two-digit day of month (integer) |
| Hour | Two-digit hour of day (integer) |
| Minute | Two-digit minute (integer) |
| Milliseconds | Milliseconds into the current minute (real) |
| DF | Dual frequency indicator, where 1 = dual-frequency solution and 0 = single-frequency solution |
| RecordType | Identifies content of data to follow (integer), valid values are (0-7). For record types 0, 2, 4, and 6, ODTK interprets the time tag as UTC time. For record types 1, 3, 5, and 7, ODTK interprets the time tag as GPS time. |
| X | X component of navigation solution in Earth Fixed coordinates, in meters (real) |
| Y | Y component of navigation solution in Earth Fixed coordinates, in meters (real) |
| Z | Z component of navigation solution in Earth Fixed coordinates, in meters (real) |
RecordTypes = 0 and 1 have the following additional fields:
| Column | Description |
|---|---|
| Sigma | 3D one-sigma uncertainty for solution, where 0 indicates not supplied, in meters (real) |
| NumSVs | Number of SVs used in navigation solution |
| PRN# | PRN numbers for SVs used in navigation solution |
RecordType = 2 and 3 (added in v6.4.2) have the following additional fields:
| Column | Description |
|---|---|
| Sigma X | One-sigma uncertainty for X component of solution, where 0 indicates not supplied, in meters (real) |
| Sigma Y | One-sigma uncertainty for Y component of solution, where 0 indicates not supplied, in meters (real) |
| Sigma Z | One-sigma uncertainty for Z component of solution, where 0 indicates not supplied, in meters (real) |
| NumSVs | Number of SVs used in navigation solution |
| PRN# | PRN numbers for SVs used in navigation solution |
RecordType = (4-7), which were added in v7.7, are identical to record types (0-3) respectively except that they have an additional integer AntennaID field directly after the record type indicator.
- PRN information is used by the filter if indicated in the GNSS receiver measurement statistics. If you set the WhiteNoiseDeweighting option to "Scale by Component DOP" or "Scale by PDOP," ODTK will use the PRN information to construct the least squares navigation solution dilution of precision matrix, which ODTK will then use to scale the specified WhiteNoise values during measurement processing.
- You cannot use comments in the NAVSOL format.
Example record (standard information):
ReceiverID Year Month Day Hour Minute Milliseconds DF RecordType
800 2003 11 15 23 59 47000 0 0 + type-specific data
Example type-specific data (type 0 information):
X Y Z Sigma NumSVs PRN1 PRN2 PRN3 �
4.0465888e+06 -5.6845461e+06 4.5752870e+03 0 8 29 28 13 11 09 08 07 03
Example type-specific data (type 4 information with Antenna ID of 1):
AntID X Y Z Sigma NumSVs PRN1 PRN2 PRN3 1 4.0465888e+06 -5.6845461e+06 4.5752870e+03 0 8 29 28 13 11 09 08 07 03
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 six-second chunks from the different Monitor stations. Each record contains data for one of these six-second chunks. There are four pseudo-ranges per record; one pseudo-range per each of four successive Z-counts where 1 Z-Count = 1.5 seconds. The first data item, the amount of Z-Counts since GPS epoch, is the Time of Transmission from the GPS SV. That time corresponds to the last (fourth) pseudo-range in the set of four.
Record Description:
| Item | Size (bytes) | Type | Description | Units |
|---|---|---|---|---|
| 1 | 8 | Double | Time of transmission (t) from GPS SV corresponding to the last (fourth) pseudo-range in the set of four | 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, which is 0 If you do not supply an antenna ID | - |
| 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 |