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SAE J2735-Draft-Rev28 [issued: 11-10-08]
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80 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
Used By: This entry is used directly by one other data structure in this standard, a MSG called
MSG_ProbeDataManagement <ASN> <XML>. In addition, this item may be used by data structures
in other ITS standards.
Remarks: From the VII POC-A team.
6.42 Data Frame: DF_SpaceVector
Use: This data frame provides a concise summary of an object's position (X,Y,Z) and motion vector
(heading and rate of speed), as well as the positioning technology employed and relative accuracy expected.
Typically, this vector is applied to stationary items, such as the location of an event, or to a moving location
where the relative offset distance and the heading vector with respect to the listener is most important. If
the position is not known, values of zero would be used in X,Y,Z or the element is not sent. If the heading
or speed is not known, values of zero shall be used, or the element is not sent. Observe that the 32-bit
values for Lat-Long provides a least significant bit (a resolution) of approximately 4 inches in North
America.
ASN.1 Representation:
SpaceVector ::= SEQUENCE {
lat Latitude OPTIONAL, -- a 4 byte value
long Longitude OPTIONAL, -- a 4 byte value
heading Heading OPTIONAL, -- a byte value from geoids north
-- of senders heading
speed Speed OPTIONAL, -- a 2 byte field in units
-- of 0.01 meters per second
vertical Elevation OPTIONAL, -- 2 byte field
-- how the position was obtained, acts
-- as a relative measure of merit
-- from [SAE-J2313::Location-tech]
accuracy PositionalAccuracy OPTIONAL
-- estimate of position accuracy
}
XML Representation:
<xs:complexType name="SpaceVector" >
<xs:sequence>
<xs:element name="lat" type="Latitude" minOccurs="0"/>
<!-- a 4 byte value -->
<xs:element name="long" type="Longitude" minOccurs="0"/>
<!-- a 4 byte value -->
<xs:element name="heading" type="Heading" minOccurs="0"/>
<!-- a byte value from geoids north
of senders heading -->
<xs:element name="speed" type="Speed" minOccurs="0"/>
<!-- a 2 byte field in units
of 0.01 meters per second -->
<xs:element name="vertical" type="Elevation" minOccurs="0"/>
<!-- 2 byte field -->
<!-- how the position was obtained, acts
as a relative measure of merit
from [SAE-J2313::Location-tech] -->
<xs:element name="accuracy" type="PositionalAccuracy" minOccurs="0"/>
<!-- estimate of position accuracy -->
</xs:sequence>
</xs:complexType>
Used By: This entry is used directly by one other data structure in this standard, a MSG called
MSG_RoadSideAlert <ASN> <XML>. In addition, this item may be used by data structures in other
ITS standards.
Remarks: The definitions for Lat-Long etc. follow those defined and found elsewhere in the SAE J2735
work on DSRC message sets, which in turn are derived from the normal LRMS definitions. The optional