Publication: Magyar Közlöny
Issue: MK-2009-104 (Year: 2009, Number: 104)
Era: 2004-2010
Section: 
Paragraph Index: 2337

b) the transponder may employ a “real time” interface which operates such that uplink data leave the transponder before the corresponding reply is generated and downlink data enter the transponder in time to be incorporated in the reply. 3.1.2.10.5.2.1.3 Extended length message interface Note.— The ELM interface extracts from, and enters into, the transponder the data exchanged between air and ground by means of the ELM protocol (3.1.2.7). 3.1.2.10.5.2.2 Indirect data transaction rates 3.1.2.10.5.2.2.1 Standard length transactions. A transponder equipped for information transfer to and from external devices shall be capable of processing the data of at least as many replies as prescribed for minimum reply rates in 3.1.2.10.3.7.2 and uplink data from interrogations being delivered at a rate of at least: 50 long interrogations in any 1-second interval 18 long interrogations in a 100-millisecond interval 8 long interrogations in a 25-millisecond interval 4 long interrogations in a 1.6-millisecond interval. Note 1.— A transponder capable of reply rates higher than the minimum of 3.1.2.10.3.7.2 need not accept long interrogations after reaching the uplink data processing limits above. Note 2.— The Mode S reply is the sole means of acknowledging receipt of the data content of a Mode S interrogation. Thus, if the transponder is capable of replying to an interrogation, the Mode S installation must be capable of accepting the data contained in that interrogation regardless of the timing between it and other accepted interrogations. Overlapping Mode S beams from several interrogators could lead to the requirement for considerable data processing and buffering. The minimum described here reduces data processing to a realistic level and the non-acceptance provision provides for notification to the interrogator that data will temporarily not be accepted. Chapter 3 Annex 10 — Aeronautical Telecommunications 3-69 22/11/07 3.1.2.10.5.2.2.2 Extended length transactions. Level 3 (2.1.5.1.3) and level 4 (2.1.5.1.4) transponders shall be able to transfer data from at least four complete sixteen segment uplink ELMs (3.1.2.7.4) in any four second interval. A level 5 transponder (2.1.5.1.5) shall be able to transfer the data from at least four complete sixteen segment uplink ELMs in any one second interval and shall be capable of accepting at least two complete sixteen segment uplink ELMs with the same II code in a 250 millisecond interval. A level 4 transponder shall be able to transmit at least one four-segment downlink ELM (3.1.2.7.7 and 3.1.2.10.3.7.3) in any one second interval. A level 5 transponder shall be able to transmit at least one sixteen segment downlink ELM in any one second interval. 3.1.2.10.5.2.2.2.1 Recommendation.— Level 3 and level 4 transponders should be able to accept at least two complete sixteen segment uplink ELMs in a 250 millisecond interval. 3.1.2.10.5.2.3 Data formats for standard length transactions and required downlink aircraft parameters (DAPs) 3.1.2.10.5.2.3.1 All level 2 and above transponders shall support the following registers: — the capability reports (3.1.2.6.10.2); — the aircraft identification protocol register 20 {HEX} (3.1.2.9); and — for ACAS-equipped aircraft, the active resolution advisory register 30 {HEX} (4.3.8.4.2.2). 3.1.2.10.5.2.3.2 Where required, DAPs shall be supported by the registers listed in Table 3-11. The formats and minimum update rates of transponder registers shall be implemented consistently to ensure interoperability. 3.1.2.10.5.2.3.3 The downlink standard length transaction interface shall deliver downlink aircraft parameters (DAPs) to the transponder which makes them available to the ground. Each DAP shall be packed into the Comm-B format (‘MB’ field) and can be extracted using either the ground-initiated Comm-B (GICB) protocol, or using MSP downlink channel 3 via the dataflash application. Note.— The formats and update rates of each register and the dataflash application are specified in the Technical Provisions for Mode S Services and Extended Squitter (Doc 9871). 3.1.2.10.5.3 Integrity of data content transfer. A transponder which employs data interfaces shall include sufficient protection to ensure error rates of less than one error in 103 messages and less than one undetected error in 107 112-bit transmissions in both directions between the antenna and each interface port. 3.1.2.10.5.4 Message cancellation. The downlink standard length transaction interface and the extended length message interface shall include the capability to cancel a message sent to the transponder for delivery to the ground, but whose delivery cycle has not been completed (i.e. a closeout has not been accomplished by a ground interrogator). Note.— One example of the need for this capability is to cancel a message if delivery is attempted when the aircraft is not within coverage of a Mode S ground station. The message must then be cancelled to prevent it from being read and interpreted as a current message when the aircraft re-enters Mode S airspace. 3.1.2.10.5.5 Air-directed messages. The transfer of this type of message requires all of the actions indicated in 3.1.2.10.5.4 plus the transfer to the transponder of the interrogator identifier of the site that is to receive the message. 3.1.2.11 ESSENTIAL SYSTEM CHARACTERISTICS OF THE GROUND INTERROGATOR Note.— To ensure that Mode S interrogator action is not detrimental to Mode A/C interrogators, performance limits exist for Mode S interrogators. Annex 10 — Aeronautical Telecommunications Volume IV 22/11/07 3-70 3.1.2.11.1 Interrogation repetition rates. Mode S interrogators shall use the lowest practicable interrogation repetition rates for all interrogation modes. Note.— Accurate azimuth data at low interrogation rates can be obtained with monopulse techniques. 3.1.2.11.1.1 All-call interrogation repetition rate. The interrogation repetition rate for the Mode A/C/S all-call, used for acquisition, shall be less than 250 per second. This rate shall also apply to the paired Mode S-only and Mode A/C-only all-call interrogations used for acquisition in the multisite mode. 3.1.2.11.1.2 Interrogation repetition rate to a single aircraft 3.1.2.11.1.2.1 Interrogations requiring a reply. Mode S interrogations requiring a reply shall not be transmitted to a single aircraft at intervals shorter than 400 microseconds. 3.1.2.11.1.2.2 Uplink ELM interrogations. The minimum time between the beginning of successive Comm-C interrogations shall be 50 microseconds. 3.1.2.11.1.3 Transmission rate for selective interrogations 3.1.2.11.1.3.1 For all Mode S interrogators, the transmission rate for selective interrogations shall be:

Source: https://magyarkozlony.hu/hivatalos-lapok/bfd0d67db9f223889f627fd618725b03526630e2/dokumentumok/d5234fd7275da04023366ab8a434989962a31bdf/letoltes