asterix 017 "Mode S Surveillance Coordination Function Messages" edition 1.3 date 2009-01-01 preamble Surveillance data exchange. items 000 "Message Type" definition Definition of the type of message in the Surveillance Coordination Network (SCN) environment element 8 table 0: Network information 10: Track data 20: Track data request 21: Track data stop 22: Cancel track data request 23: Track data stop acknowledgement 30: New Node / Change-over Initial or intermediate message segment 31: New Node / Change-over Final or only message segment 32: New Node / Change-over Initial or intermediate message segment reply 33: New Node / Change-over Final or only message segment reply 110: Move node to new cluster state; 111: Move node to new cluster state acknowledgement remark NOTE: - Message types 30 to 33 are specific to POEMS stations. 010 "Data Source Identifier" definition Identification of the source node for the SCN data group SAC "System Area Code" element 8 raw SIC "System Identification Code" element 8 raw remark NOTE: - The up-to-date list of SACs is published on the Eurocontrol Web Site (http://www.eurocontrol.int/asterix). 012 "Data Destination Identifier" definition Identification of the destination node for the SCN data. group SAC "System Area Code" element 8 raw SIC "System Identification Code" element 8 raw remark NOTE: - The up-to-date list of SACs is published on the Eurocontrol Web Site (http://www.eurocontrol.int). 045 "Calculated Position in WGS-84 Coordinates" definition Calculated Position in WGS-84 Coordinates. group LAT "Latitude" element 24 signed quantity 180/2^25 "°" >= -90 <= 90 LON "Longitude" element 24 signed quantity 180/2^25 "°" >= -180 < 180 remark NOTE: - See Annex A for calculation details 050 "Flight Level in Binary Representation" definition Flight Level of the Aircraft group V "" element 1 table 0: Code validated 1: Code not validated G "" element 1 table 0: Default 1: Garbled code / Error correction applied ALT "Altitude" element 14 unsigned quantity 1/2^2 "FL" remark NOTES: 1. The value shall be within the range described by ICAO Annex 10 2. Bit-15 (G) is set to one when an error correction has been attempted 3. In case of a track miss (coasted position) the flight level sent will be either he predicted flight level from the vertical tracking or the last measured flight level, if no vertical tracking is performed. Bit 7 (FLT) of I017/240 (Track Status) indicates whether vertical tracking was performed or not. 070 "Mode 3/A Code in Octal Representation" definition Mode 3/A code converted into octal representation. group V "" element 1 table 0: Code validated 1: Code not validated G "" element 1 table 0: Default 1: Garbled code L "" element 1 table 0: Mode-3/A code derived from the reply of the transponder 1: Smoothed Mode-3/A code not extracted during the last scan spare 1 MODE3A "Mode 3/A Reply in Octal Representation" element 12 string octal remark NOTES: 1. Bit 15 is set to one when an error correction has been attempted 2. The data could be used to correlate tracks with non unique Mode S addresses 140 "Time of Day" definition Absolute time stamping expressed as Coordinated Universal Time (UTC) time. element 24 unsigned quantity 1/2^7 "s" < 86400 remark NOTE: - The time of day is reset to zero each day at midnight 200 "Track Velocity in Polar Co-ordinates" definition Calculated track velocity expressed in polar co-ordinates. The heading is the heading with respect to the geographical north at the aircraft position. For clarification see annex A, paragraph5. group GSP "Calculated Groundspeed" element 16 unsigned quantity 1/2^14 "NM/s" HDG "Calculated Heading" element 16 unsigned quantity 360/2^16 "°" 210 "Mode S Address List" definition Repetitive Data Item starting with a one-octet Repetition Factor followed by at least one Mode S Address of 3-octets length. repetitive 8 element 24 raw remark NOTE: - This data item shall be sent even if there is no Mode S Address. In this case it is reduced in length to one octet only (REP =0) with all bits set to zero. 220 "Aircraft Address" definition Aircraft address (24-bits Mode S address) assigned uniquely to each aircraft. element 24 raw 221 "Duplicate Address Reference Number (DRN)" definition A number uniquely identifying the aircraft in case the Mode-S Address is not unique. element 16 raw remark NOTE: 1. The DRN shall be added to the Track Data message, if the radar node, which is sending the Track Data messages, detects two or more aircraft with the same mode-S address in its coverage. How the numbers are generated is determined by the sending station. 2. The radar node receiving the Track Data Messages containing a DRN shall add this DRN in the corresponding ”Cancellation of Track Data” message. 3. The DRN is used to associate the ”Cancellation of Track Data” message with the corresponding ”Track Data” messages. 4. The cluster controller node will not use the DRN in the track data message, because there is no cancellation. 230 "Transponder Capability" definition Communications capability of the transponder received in the All-Call reply when the aircraft is initially acquired. group CA "Communications Capability of the Transponder" element 3 table 0: No communications capability (surveillance only), no ability to set CA code 7 either airborne or on the ground 1: Reserved 2: Reserved 3: Reserved 4: At Least Comm. A and Comm. B capability and the ability to set CA code 7 and on the ground 5: At Least Comm. A and Comm. B capability and the ability to set CA code 7 and airborne 6: At Least Comm. A and Comm. B capability and the ability to set CA code 7 and either airborne or on the ground 7: Signifies the DR field is not equal to 0 or the FS field equals 2, 3, 4 or 5 and either airborne or on the ground SI/II-capabilities of the Transponder SI "SI/II-capabilities of the Transponder" element 1 table 0: Transponder SI capable 1: Transponder not SI capable spare 4 240 "Track Status" definition Status of the track position group CST "Track Coasted" element 1 table 0: Measured position 1: No measured position (coasted) FLT "Flight Level Tracking" element 1 table 0: Last Measured Flight Level 1: Predicted Flight Level spare 6 remark NOTE: - This item shall not be sent when CST and FLT equal zero. 350 "Cluster Station/Node List" definition List of stations/nodes stored in the known network topology maintained by NMP. The topology to be reported is as defined in the SCN ICD. repetitive 8 group SAC "System Area Code" element 8 raw SIC "System Identification Code" element 8 raw remark NOTE: - The up-to-date list of SACs is published on the Eurocontrol Web Site (http://www.eurocontrol.int). 360 "Cluster Controller Command State" definition Defines the current mode and state in which a cluster station, the radar node taking part in the cluster, should be operating. element 8 raw remark NOTE: - The Cluster Controller will use this field to select the state in which a cluster station should be operating and the cluster station will use this field to indicate to the cluster controller the adopted state. SP "Special Purpose Field" definition Special Purpose Field explicit sp uap 010 012 000 350 220 221 140 045 070 050 200 230 240 210 360 - - - - - SP