Technical Provisions for Mode S Services and Extended Squitter

C-2 Technical Provisions for Mode S Services and Extended Squitter
Notes.—
DRAFT - Working Paper ASP TSGWP11-01 for review by the TSG during the meeting in June 2011 in Paris
Register
number
Table C-1. Register Allocation
Assignment
Maximum update
interval
05 16 Extended Squitter Airborne Position 0.2 s
06 16 Extended Squitter Surface Position 0.2 s
07 16 Extended Squitter Status 1.0 s
08 16 Extended Squitter Identification and Category 15.0 s
09 16 Extended Squitter Airborne Velocity 1.3 s
0A 16 Extended Squitter Event-Driven Information variable
61 16 Extended Squitter Aircraft Status 1.0 s
62 16 Target State and Status Information 0.5 s
63 16-64 16 Reserved for Extended Squitter
65 16 Extended Squitter Aircraft Operational Status 2.5 s
66 16-6F 16 Reserved for Extended Squitter
1. The Register number is equivalent to the BDS B-Definition Subfield (BDS) value (see §2.2.14.4.20.b of
RTCA DO-181D [EUROCAE ED-73C, §3.18.4.18.b]).
2. Register 0A16 is not to be used for GICB or ACAS crosslink readout.
3. The term “minimum update rate” is used in this Manual. The “minimum update rate” is obtained when data is
loaded in one Register field once every “maximum update interval.”
4. If Extended Squitter is implemented, then Register 0816 is not cleared or ZEROed once either Flight
Identification or Aircraft Registration data has been loaded into the Register during the current power-on cycle.
Register 0816 is not cleared since it provides information that is fundamental to track file management in the ADS-B
environment. Refer to §C.2.4.3.3 for implementation guidelines regarding Register 0816.
5. These registers define version 2 extended squitters
Draft
C.2.1.1 The details of the data to be entered into the registers assigned for Extended Squitter shall be as defined in
this Appendix. Table C-1 specifies the maximum update interval at which the appropriate transponder register(s)
shall be reloaded with valid data. Any valid data shall be reloaded into the relevant field as soon as it becomes
available at the Mode S Specific Services Entity (SSE) interface regardless of the update rate. Unless otherwise
specified, if data are not available for a time no greater than twice the specified “maximum update interval,” or 2
seconds (whichever is the greater), then the status bit (if provided) shall indicate that the data in that field are invalid,
and the field shall be ZEROed.
C.2.1.2 The register number shall be equivalent to the Comm-B data selector (BDS) value used to address that
register (see §3.1.2.6.11.2.1 of Annex 10, Volume IV).
C.2.2 GENERAL CONVENTIONS ON DATA FORMATS
For requirements on the validity of data, see §A.2.2.1.
C.2.2.1 VALIDITY OF DATA
C.2.2.2 REPRESENTATION OF NUMERICAL DATA
Numerical data shall be represented as specified in §A.2.2.2.
DRAFT - Working Paper ASP TSGWP11-01 for review by the TSG during the meeting in June 2011 in Paris