Spatial Reference Manual
Page 133 of 158
Version 4.4
04/06/2019
13.9.34
External Depth Packet
External Depth Packet
Packet ID
53
Length
8
Field
#
Bytes
Offset
Data
Type
Size
Description
1
0
fp32
4
Depth (m)
2
4
fp32
4
Depth standard deviation (m)
Table 78: External depth packet
13.9.35
Geoid Height Packet
This packet provides the offset at the current location between the WGS84 ellipsoid
and the EGM96 geoid model. This can be used to determine the current height above
mean sea level and also depth through the following equations:
Height Above Mean Sea Level = WGS84 Height – Geoid Height
Depth = Geoid Height – WGS84 Height
WGS84 Height is the height at the current location in the System State packet.
Geoid Height Packet
Packet ID
54
Length
4
Field
#
Bytes
Offset
Data
Type
Size
Description
1
0
fp32
4
Geoid height (m)
Table 79: Geoid height packet
13.9.36
RTCM Corrections Packet
This packet is used to encapsulate RTCM v3 differential and RTK correction data to be
sent to Spatial's internal GNSS receiver for differential and RTK GNSS functionality.
RTCM Corrections Packet
Packet ID
55
Length
Variable, up to 255 bytes
Field
#
Bytes
Offset
Data
Type
Size
Description
1
0
RTCM corrections data
Table 80: RTCM corrections packet