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SAE J2735-Draft-Rev26 [issued: 09-18-08]
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This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="localTravelerInformation" type="local:TravelerInformation"
minOccurs="0"/>
</xs:sequence>
</xs:complexType>
In addition, this item may be used by data structures in other ITS standards.
6. Data Frames
DSRC data frames for this volume shall consist of the following data frames. Each data frame shall be
further divided into specific entries and elements as defined in this clause. Typically, these entries are
made up of content internal to this document (made up of entries that are either atomic or complex) and
content external to this document (from other functional areas and companion volumes).
Definitions for these messages are presented in the following subclauses. The ASN is presented in a
section called "ASN.1 Representation," formerly called "Format." In a similar manner, the equivalent
XML expression is presented in a section called "XML Representation" which follows the translation rule
set cited in Clause Two.
Regarding equivalent entries to be placed into a data registry. The mapping between data elements and
analogous meta data entries have been explained in other ITS stds. In addition, some meta information is
constant in this entire standard and need not be repeated with each entry here. These include the sponsor
and steward of the entries [SAE], the registration status [registered once the standard is adopted] and the
revision date [the date of the standards adoption]. The class name is always ITS.
The productions of ASN.1 which follow shall be considered normative in nature. While the majority of the
normative content is reflected in the actual syntax of the ASN.1 some entries also have additional
statements in the ASN.1 comments which shall be considered to be normative as well. In addition, the
commentary provided with each entry may also provide additional normative restrictions on the proper use
of the entry which shall be followed. The XML productions follow directly from the ASN.1 specifications
and the same rules shall be applied.
6.1 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. If the heading or speed is not known,
values of zero shall be used. 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, -- a 4 byte value
long Longitude, -- a 4 byte value
heading Heading, -- a 1 byte value from geoids north
speed Speed, -- a 2 byte field in units
-- of 0.01 meters per second
vertical Elevation, -- 2 byte field
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