Geolocation Tracking Data File (.geoloc)
Format for Geolocation Tracking Data File
Each line contains a single record. Time Difference of Arrival (TDOA) and Frequency Difference of Arrival (FDOA) measurements are constructed by computing the difference of signal reception observations from two signal paths in the sense of (path 2 minus path 1). Each record begins with the following standard information, consisting of record type and time tag information, where the time tag is the time of signal reception along path 1. The standard fields are defined as (space delimited):
RecordType Year Month Day Hour Minute Seconds TimeScale
| Field | Description | Type |
|---|---|---|
| RecordType | Identifies content of data to follow | Integer |
| Year | four-digit year | Integer |
| Month | two-digit month, Jan = 01 | Integer |
| Day | two-digit day of month | Integer |
| Hour | two-digit hour of day | Integer |
| Minute | two-digit minute of hour | Integer |
| Seconds | Seconds | Real |
| TimeScale | 0 - UTC, 1 - GPS | Integer |
RecordType = 0 is used to describe ground-based TDOA and FDOA measurements (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S1XID | Identifier for satellite 1 transponder (-1 indicates not supplied) | Integer |
| S1XDelay | Delay (ns) for satellite 1 transponder (-1 indicates not supplied) | Real |
| S1XTrans | Additive frequency translation in Hz for sat 1 transponder (0 indicates not supplied) | Real |
| S2ID | Tracking identifier for satellite 2 | Integer |
| S2XID | Identifier for satellite 2 transponder (-1 indicates not supplied) | Integer |
| S2XDelay | Delay (ns) for satellite 2 transponder (-1 indicates not supplied) | Real |
| S2XTrans | Additive frequency translation in Hz for satellite 2 transponder (0 indicates not supplied) | Real |
| RID | Tracking identifier for receive station | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
RecordType = 1 is used to describe ground-based TDOA and TDOA Dot measurements (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S1XID | Identifier for satellite 1 transponder (-1 indicates not supplied) | Integer |
| S1XDelay | Delay (ns) for satellite 1 transponder (-1 indicates not supplied) | Real |
| S1XTrans | Additive freq translation in Hz for satellite 1 transponder (0 indicates not supplied) | Real |
| S2ID | Tracking identifier for satellite 2 | Integer |
| S2XID | Identifier for satellite 2 transponder (-1 indicates not supplied) | Integer |
| S2XDelay | Delay (ns) for satellite 2 transponder (-1 indicates not supplied) | Real |
| S2XTrans | Additive frequency translation in Hz for satellite 2 transponder (0 indicates not supplied) | Real |
| RID | Tracking identifier for receive station | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| TDOA Dot Validity | Indicator of a valid TDOA Dot measurement (1 - valid, 0 - invalid) | Integer |
| TDOA Dot | Time derivative of TDOA (path 2 - path 1) (unitless) | Real |
| SigmaTDOADot | White noise uncertainty in TDOA Dot (unitless) (0 indicates not specified) | Real |
RecordType = 2 is used to describe ground-based, singly differenced TDOA and FDOA (computed as emitter 2 minus emitter 1, each DOA is path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID1 | Tracking identifier for the emitter | Integer |
| EFreq1 | Frequency of transmission from emitter 1 in Hz (-1 indicates not supplied) | Real |
| EID2 | Tracking identifier for the emitter 2 | Integer |
| EFreq2 | Frequency of transmission from emitter 2 in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S1X1ID | Identifier for satellite 1 transponder used with emitter 1 (-1 indicates not supplied) | Integer |
| S1X1Delay | Delay (ns) for satellite 1 transponder used with emitter 1 (-1 indicates not supplied) | Real |
| S1X1Trans | Additive frequency translation in Hz for satellite 1 transponder used with emitter 1 (0 indicates not supplied) | Real |
| S1X2ID | Identifier for satellite 1 transponder used with emitter 2 (-1 indicates not supplied) | Integer |
| S1X2Delay | Delay (ns) for satellite 1 transponder used with emitter 2 (-1 indicates not supplied) | Real |
| S1X2Trans | Additive frequency translation in Hz for sat 1 transponder used with emitter 2 (0 indicates not supplied) | Real |
| S2ID | Tracking identifier for satellite 2 | Integer |
| S2X1ID | Identifier for satellite 2 transponder used with emitter 1 (-1 indicates not supplied) | Integer |
| S2X1Delay | Delay (ns) for satellite 2 transponder used with emitter 1 (-1 indicates not supplied) | Real |
| S2X1Trans | Additive frequency translation in Hz for satellite 2 transponder used with emitter 1 (0 indicates not supplied) | Real |
| S2X2ID | Identifier for satellite 2 transponder used with emitter 2 (-1 indicates not supplied) | Integer |
| S2X2Delay | Delay (ns) for satellite 2 transponder used with emitter 2 (-1 indicates not supplied) | Real |
| S2X2Trans | Additive frequency translation in Hz for satellite 2 transponder used with emitter 2 (0 indicates not supplied) | Real |
| RID | Tracking identifier for receive station | Integer |
| TDOAValidity | Indicator of a valid SD TDOA measurement (1 - valid, 0 - invalid) | Integer |
| SDTDOA | Singly differenced (emitter2 - emitter1) time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaSDTDOA | White noise uncertainty in SD TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid SD FDOA measurement (1 - valid, 0 - invalid) | Integer |
| SDFDOA | Singly differenced (emitter2 - emitter1) freq difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaSDFDOA | White noise uncertainty in SD FDOA in Hz (0 indicates not specified) | Real |
RecordType = 3 is used to describe space-based TDOA and FDOA measurements (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S2ID | Tracking identifier for satellite 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
RecordType = 4 is used to describe space-based TDOA and TDOA Dot measurements (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S2ID | Tracking identifier for satellite 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| TDOA Dot Validity | Indicator of a valid TDOA Dot measurement (1 - valid, 0 - invalid) | Integer |
| TDOA Dot | Time derivative of TDOA (path 2 - path 1) (unitless) | Real |
| SigmaTDOADot | White noise uncertainty in TDOA Dot (0 indicates not specified) (unitless) | Real |
RecordType = 5 is used to describe TDOA and FDOA measurements from a space-based emitter to two ground stations (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| R1ID | Tracking identifier for receive station 1 | Integer |
| R2ID | Tracking identifier for receive station 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
RecordType = 6 is used to describe TDOA, FDOA, and FDOA Dot measurements from a space-based emitter to two ground stations (computed as path 2 minus path 1) and has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| R1ID | Tracking identifier for receive station 1 | Integer |
| R2ID | Tracking identifier for receive station 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
| FDOADotValidity | Indicator of a valid FDOA Dot measurement (1 - valid, 0 - invalid) | Integer |
| FDOADot | Frequency difference of arrival rate (path 2 - path 1) in Hz/sec | Real |
| SigmaFDOADot | White noise uncertainty in FDOA Dot in Hz/sec (0 indicates not specified) | Real |
RecordType = 7 is used to describe TDOA and TDOA Dot measurements (computed as path 2 minus path 1), where signals from two emitters pass through a single satellite to a single ground station. This record type has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| E1ID | Tracking identifier for emitter 1 | Integer |
| E1Freq | Frequency of emitter 1 transmission in Hz (-1 indicates not supplied) | Real |
| E2ID | Tracking identifier for emitter 2 | Integer |
| E2Freq | Frequency of emitter 2 transmission in Hz (-1 indicates not supplied) | Real |
| SID | Tracking identifier for the satellite | Integer |
| RID | Tracking identifier for the receive facility | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| TDOA Dot Validity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA Dot | Time derivative of TDOA (path 2 - path 1) (unitless) | Real |
| SigmaTDOADot | White noise uncertainty in TDOA Dot (0 indicates not specified) (unitless) | Real |
RecordType = 8 is used to describe space-based TDOA and FDOA measurements (computed as path 2 minus path 1), where signals are from a single space-based emitter to two space-based receivers. The format of RecordType 8 records is identical to that of RecordType 3.
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S2ID | Tracking identifier for satellite 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
RecordType = 9 is used to describe ground-based TDOA and FDOA measurements (computed as path 2 minus path 1), where the signal paths are emitter-satellite1-receiver1 and emitter-satellite2-receiver2. This record type has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for satellite 1 | Integer |
| S1XID | Identifier for satellite 1 transponder (-1 indicates not supplied) | Integer |
| S1XDelay | Delay (ns) for satellite 1 transponder (-1 indicates not supplied) | Real |
| S1XTrans | Additive frequency translation in Hz for satellite 1 transponder (0 indicates not supplied) | Real |
| S2ID | Tracking identifier for satellite 2 | Integer |
| S2XID | Identifier for satellite 2 transponder (-1 indicates not supplied) | Integer |
| S2XDelay | Delay (ns) for satellite 2 transponder (-1 indicates not supplied) | Real |
| S2XTrans | Additive frequency translation in Hz for satellite 2 transponder (0 indicates not supplied) | Real |
| R1ID | Tracking identifier for receive station 1 | Integer |
| R2ID | Tracking identifier for receive station 2 | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
RecordType = 10 is used to describe bistatic ground FDOA measurements and TDOA measurements, computed as path 2 minus path 1. Signal path 1 is direct from the emitter to the receiver. Signal path 2 passes through a transponder on a relay spacecraft or is reflected by the spacecraft, with the signal ending at the receiver. These measurement types are applicable to the tracking of satellites using radio signals. This record type has the following additional space-delimited fields:
| Field | Description | Type |
|---|---|---|
| EID | Tracking identifier for the emitter | Integer |
| EFreq | Frequency of transmission in Hz (-1 indicates not supplied) | Real |
| S1ID | Tracking identifier for the satellite | Integer |
| S1XID | Identifier for satellite transponder (-1 indicates not supplied) | Integer |
| S1XDelay | Delay (ns) for satellite transponder (-1 indicates not supplied) | Real |
| S1XTrans | Additive frequency translation in Hz for sat transponder (0 indicates not supplied) | Real |
| RID | Tracking identifier for receive station | Integer |
| TDOAValidity | Indicator of a valid TDOA measurement (1 - valid, 0 - invalid) | Integer |
| TDOA | Time difference of arrival (path 2 - path 1) in seconds | Real |
| SigmaTDOA | White noise uncertainty in TDOA in seconds (0 indicates not specified) | Real |
| FDOAValidity | Indicator of a valid FDOA measurement (1 - valid, 0 - invalid) | Integer |
| FDOA | Frequency difference of arrival (path 2 - path 1) in Hz | Real |
| SigmaFDOA | White noise uncertainty in FDOA in Hz (0 indicates not specified) | Real |
Notes:
The transponder delay and transponder frequency translation data is not passed to the filter.
Example record (standard information):
RecordType Year Month Day Hour Minute Seconds
0 2006 11 15 00 00 15.0 + type-specific data
Example type-specific data (type 0 information):
EID EFreq S1ID S1XID S1XDelay S1XTrans S2ID S2XID S2XDelay S2XTrans RID TDOAValidity TDOA SigmaTDOA FDOAValidity FDOA SigmaFDOA
101 14321.0e+06 1111 -1 -1 0 2222 -1 -1 0 300 1 0.01254653 0 1 1.65372 0