Data record subtype 7: Enhanced position (record type 29)

The following table shows the additional records provided in Report Packet 57h when the Enhanced Position record is enabled with Command Packet 56h.

Where increments are present, divide the value by the increment to scale to the indicated units.

For example: LONGITUDE/2^39

Subtype 7: Enhanced Position (Record 29)

Byte

Item

Type

Value

Meaning

8

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

9–10

WEEK NUMBER

2 (short)

 

GPS week number of the observation.

11–14

RECEIVER TIME

4 (long)

msec

Receiver time (milliseconds of the week) of the observation.

15

RECEIVER MOTION STATE

1 (byte)

 

Valid values are 0 (kinematic) or 1 (static).

16

NUMBER SVs TRACKED

1 (byte)

 

Number of SVs actually tracked.

17

NUMBER OF SVs USED IN SOLUTION

1 (byte)

 

Number of SVs actually used in calculating the solution.

18

RESERVED

1 (byte)

 

RESERVED

19

POSITION SYSTEM FLAGS

1 (byte)

 

See Position systems flags values.

20

POSITION SOLUTION MODE

1 (byte)

 

See Position solution mode values.

21

POSITION AUGMENTATION TYPE

1 (byte)

 

See Position augmentation type values.

22

POSITION PROCESSING TYPE

1 (byte)

 

See Position processing type values.

Position Block (53 bytes)

23

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

24–29

LATITUDE

6 (integer)

Degrees

Range = +/-90 degrees. Increment = 2^40, approximately 9.1e–13 degrees.

30–35

LONGITUDE

6 (integer)

Degrees

Range = +/-180 degrees. Increment = 2^39, approximately 1.8e–12 degrees.

36–39

ALTITUDE

4 (long)

Meters

Range = +/-524,288 m. Increment = 2^12, approximately 0.24 mm.

40–43

VELOCITY N

4 (long)

Meters/sec

Range = +/-1024 m/s. Increment = 2^21, approximately 0.00048 mm/s.

44–47

VELOCITY E

4 (long)

Meters/sec

Range = +/-1024 m/s. Increment = 2^21, approximately 0.00048 mm/s.

48–51

VELOCITY U

4 (long)

Meters/sec

Range = +/-1024 m/s. Increment = 2^21, approximately 0.00048 mm/s.

52–55

RECEIVER CLOCK OFFSET

4 (long)

Milliseconds

Range = +/-32 msec. Increment = 2^26, approximately 1.5e–8 msec.

56–59

RECEIVER CLOCK DRIFT

4 (long)

Clock drift in PPM

Range = +/-16,384 ppm. Increment = 2^17, approximately 7.6e–6 ppm.

60–61

HDOP

2 (short)

Unitless

Range = 0–4096. Increment = 2^4, approximately 0.0625.

62–63

VDOP

2 (short)

Unitless

Range = 0–4096. Increment = 2^4, approximately 0.0625.

64–65

TDOP

2 (short)

Unitless

Range = 0–4096. Increment = 2^4, approximately 0.0625.

66–67

1SIGMA N

2 (short)

Meters

Range = 0–32 m. Increment = 2^11, approximately 4.9e–4 m.

68–69

1SIGMA E

2 (short)

Meters

Range = 0–32 m. Increment = 2^11, approximately 4.9e–4 m.

70–71

1SIGMA U

2 (short)

Meters

Range = 0–32 m. Increment = 2^11, approximately 4.9e–4 m.

72–73

RMS

2 (short)

Meters

Range = 0–4 m. Increment = 2^14, approximately 6.1e–5 m.

74–75

UNIT STD DEV

2 (short)

Square root of the unit variance

Range = 0–32. Increment = 2^11, approximately 4.9e–4.

RTK Solutions Block: available if POSITION AUGMENTATION TYPE is 3, 4, 5, or 6 (5 bytes).

 

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

 

RTK MODE

1 (byte)

0 or 1

Valid values are 0 (synchronized) or 1 (low latency).

 

AGE OF DATA

2 (short)

Seconds

Range is 0 to 1000 seconds, increment = 2^6.

 

RESERVED

1 (byte)

 

 

GLONASS Block: Available if bit 1 is set in POSITION SYSTEMS FLAGS (12 bytes).

 

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

 

GPS GLONASS SYSTEM TIME OFFSET

4 (long)

Nanoseconds

Range = +/-32,768 ns. Increment = 2^16.

 

GPS GLONASS TIME DRIFT

4 (long)

Nanoseconds/sec

Range = +/-32,768 ns. Increment = 2^16.
 

GLONASS FLAGS

1 (byte)

 

Bit 0 set: GLONASS TDOP.

 

GLONASS TDOP

2 (short)

If present, see GLONASS FLAGS bit 0

Increment = 2^4.

Inter-System Clock Offset Block: Available if bit 4 is set in POSITION SYSTEMS FLAGS (?? bytes).

 

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

 

INTER-SYSTEM CLOCK OFFSET HEADER

1 (byte)

 

Bit 0-3: Satellite clock system to which time offsets are referenced. See Inter-System Clock Offset SV System bit values.

Bit 4-6: Number of System Time Offsets stored (n = 0-7)
Bit 7: One more header byte follows.

Repeated for the number of system time offsets stored.

 

INTER-SYSTEM CLOCK OFFSET INFO

1 (byte)

 

Bit 0-3: Satellite clock system. See Inter-System Clock Offset SV System bit values.

Bit 4-6: Number of bytes (“M”)
Bit 7: One more info byte follows.

 

INTER-SYSTEM CLOCK OFFSET

"M" bytes

milliseconds

This is an M-byte signed integer in units of milliseconds/2^28. The lowest bit has a value of 0.0037 ns or 1.12 mm. The range based on the number of bytes is:

1 bytes: +/- 0.47 ns
2 bytes: +/- 122.07 ns
3 bytes: +/- 31250.00 ns (31 us)
4 bytes: +/- 8 ms
5 bytes: +/- 2.048 s
6 bytes: +/- 524.29 s
7 bytes: +/- 37.283 hours ( LSB = 4.48 mm if top 2 bits of 7th byte are used )

SV Block (SV ID, SV TYPE, and SV FLAGS are repeated for the number of SVs tracked. Trimble recommends using the BLOCK LENGTH to determine the number of SVs (4 bytes).

 

BLOCK LENGTH

1 (byte)

 

Indicates the length of the current data block, including the BLOCK LENGTH byte.

 

SV ID

1 (byte)

 

 

 

SV TYPE

1 (byte)

 

SV TYPE is the GNSS system or satellite type. Defined values are:

0: GPS
1: SBAS (WAAS, EGNOS, MSAS, etc.)
2: GLONASS
3: Galileo
4: QZSS
9: NavIC
10: BeiDou (old firmware versions may have identified BeiDou as “5” or “7” before the ICD was released or fully implemented).

 

SV FLAGS

1 (byte)

SV FLAGS is a bitmapped field with the following values:

Bit 0: SV unhealthy
Bit 1: SV used in position solution
Bit 2: RAIM fault
Bit 3–7: RESERVED

Repeat previous bytes for remaining satellites in constellation

---------- End of Subtype 7 ----------