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.

Group

I247/010/SAC - System Area Code

Element

bit size: 8

Raw Content

I247/010/SIC - System Identification Code

Element

bit size: 8

Raw Content

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.

Element

bit size: 8

Raw Content

The service identification is allocated by the system.

I247/140 - Time of Day

definition: Absolute time stamping expressed as UTC.

Element

bit size: 24

Unsigned quantity

LSB = 1/2⁷ s ≈ 7.8125e − 3 s

unit: "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.

Repetitive

Regular, 1 byte(s) REP field size.

Group

I247/550/CAT - Category

Element

bit size: 8

Unsigned integer

I247/550/MAIN - Main Version Number

Element

bit size: 8

Unsigned integer

I247/550/SUB - Sub Version Number

Element

bit size: 8

Unsigned integer

I247/RE - Reserved Expansion Field

definition: Expansion

Explicit (ReservedExpansion)

I247/SP - Special Purpose Field

definition: Special Purpose Field

Explicit (SpecialPurpose)

User Application Profile

• 1: I247/010 - Data Source Identifier
• 2: I247/015 - Service Identification
• 3: I247/140 - Time of Day
• 4: I247/550 - Category Version Number Report
• Spare
• 6: I247/SP - Special Purpose Field
• 7: I247/RE - Reserved Expansion Field
• (FX) - Field extension indicator