Asterix category 247 - Version Number Exchange
category: 247
edition: 1.2
date: 2008-02-01
Preamble
Surveillance data exchange.
Description of standard data items
I247/010 - Data Source Identifier
Definition: Identification of the radar station from which the data are received.
Structure:
I247/010/SAC - System Area Code
- 8 bits [
........]- raw value
I247/010/SIC - System Identification Code
- 8 bits [
........]- raw value
- Note:
-
The defined SACs are on the EUROCONTROL ASTERIX website (www.eurocontrol.int/asterix)
I247/015 - Service Identification
Definition: Identification of the service provided to one or more users.
Structure:
- 8 bits [
........] - raw value
The service identification is allocated by the system.
I247/140 - Time of Day
Definition: Absolute time stamping expressed as UTC.
Structure:
- 24 bits [
........................] - unsigned quantity
- unit: “s”
- LSB = 1/27 s ≈ 7.81e − 3 s
The time of day value is reset to zero each day at midnight.
I247/550 - Category Version Number Report
Definition: Version number of Categories used.
Structure:
Repetitive item, repetition factor 8 bits.
I247/550/CAT - Category
- 8 bits [
........]- unsigned integer
I247/550/MAIN - Main Version Number
- 8 bits [
........]- unsigned integer
I247/550/SUB - Sub Version Number
- 8 bits [
........]- unsigned integer
I247/RE - Reserved Expansion Field
Definition: Expansion
Structure:
Explicit item (RE)
I247/SP - Special Purpose Field
Definition: Special Purpose Field
Structure:
Explicit item (SP)
User Application Profile for Category 247
I247/010- Data Source Identifier
I247/015- Service Identification
I247/140- Time of Day
I247/550- Category Version Number Report
(spare)
I247/SP- Special Purpose Field
I247/RE- Reserved Expansion Field
(FX)- Field extension indicator