1、November 2015DEUTSCHE NORM DKE Deutsche Kommission Elektrotechnik Elektronik Informationstechnik in DIN und VDEDIN-Normenstelle Schiffs- und Meerestechnik (NSMT)Preisgruppe 36DIN Deutsches Institut fr Normung e. V. Jede Art der Vervielfltigung, auch auszugsweise, nur mit Genehmigung des DIN Deutsche
2、s Institut fr Normung e. V., Berlin, gestattet.ICS 47.020.70!%Cw1 kHz, average the samples over a sliding 20 ms period and over a 4 s interval determine the minimum period value. Maintain a history of 15 such intervals. The minimum of all 15 intervals is the background level. When insufficient free
3、slots are available, and there are slots that contain energy levels that exceed a free slot without a decodable message, then they shall be considered “garbled slots”. The algorithm shall then select “garbled slots” according to the lowest energy level first. Intentional slot reuse, in accordance wi
4、th Recommendation ITU-R M.1371 shall be performed after free and “garbled slots” are exhausted. 4.4 Message scheduling (See 6.6) 22 DIN EN 62320-3:2015-11 EN 62320-3:2015 4.4.1 Station report A repeater station has to identify itself by transmitting a repeater status report using Message 26 every 6
5、min by default (value shall be configurable within 60 min), alternating between channel A and B. The access scheme shall preferably be ITDMA or SOTDMA where possible. FATDMA or RATDMA may be used, depending on the reporting interval. If the access scheme is configured as depending on the reporting i
6、nterval the following access scheme shall be used: 1 min and 7 min: RATDMA In all cases FATDMA slots shall be used, if available. If the repeater station is not programmed with a valid identifier (MMSI) or is not configured to transmit a repeater status report then all repeating functions shall be d
7、isabled. If the repeater station is configured to disable all repeating functions, the repeater status report transmission is not required. If the repeater station is integrated into a base station or an AIS AtoN station, the repeater station shall have its own MMSI in accordance with Recommendation
8、 ITU-R M.585. 4.4.2 Repeater station identification message structure Table 6 defines the contents of the Message 26 which identifies the repeater station on the VDL. If the repeater station is built into a base station or an AIS AtoN, this message transmission is also required. 23 DIN EN 62320-3:20
9、15-11 EN 62320-3:2015 Table 6 Contents of Message 26 used for repeater station identification Parameter Number of bits Description Message ID 6 Always 26 Repeat indicator 2 Always 0 Source ID 30 The ID shall be as defined in 4.4.1 Destination indicator 1 Always 0 = Broadcast Binary data flag 1 Alway
10、s 1 = Structured message Application identifier 16 DAC = 995, FI = 0 Longitude 28 Longitude in 1/10 000 min (180, East = positive (as per 2s complement), West = negative (as per 2s complement); 181= (6791AC0h) = not available = default) Latitude 27 Latitude in 1/10 000 min (90, North = positive (as
11、per 2scomplement), South = negative (as per 2s complement); 91 = (3412140h) = not available = default) Alarm status 16 See Table 7 Messages repeated in last frame 9 0 to 400 messages Spare 12 Not used. Shall be set to zero. Reserved for future use. Communication state selector 1 0 = SOTDMA communica
12、tion state follows 1 = ITDMA communication state follows Communication state 19 SOTDMA communication state (see ITU-R M.1371-5, 3.3.7.2.2, Annex 2), if communication state selector flag is set to 0, or ITDMA communication state (Recommendation ITU-R M.1371-5, 3.3.7.3.2, Annex 2), if communication st
13、ate selector flag is set to 1 Number of bits 168 Occupies 1 slot Table 7 Alarm status definition for Table 6 Alarm status bit Alarm condition 0 0 = default , 1 = Automatic downsampling active 1 0 = default , 1 = Downsampling limit exceeded 2 0 = default , 1 = Transmitter malfunction 3 0 = default ,
14、1 = Receiver malfunction channel A 4 0 = default , 1 = Receiver malfunction channel B 5 0 = default , 1 = UTC lost 6 0 = default , 1 = Internal position lost 7 0 = default , 1 = VSWR failure 8 0 = default , 1 = AIS-SART received 9 0 = default , 1 = Slot re-use during last frame 10 0 = default , 1 =
15、Battery low 1115 Shall be 0 = default. Reserved for future use 24 DIN EN 62320-3:2015-11 EN 62320-3:2015 4.4.3 Broadcast active AIS-SART message (See 6.5.6) Only one message from the active AIS-SART burst shall be repeated. The active AIS-SART message takes priority over any other message in the tra
16、nsmit queue. Upon reception of an active AIS-SART message with no valid position, the repeater station shall transmit a broadcast binary Message 8 with DAC = 995, FI = 9 as shown in Table 8. The message shall contain the unique ID of the active AIS-SART and the RSSI level of the received message. Th
17、e AIS-SART shall not be subject to downsampling. Table 8 Message 8 structure with AIS-SART related content Parameter Number of bits Description Message ID 6 Always 8 Repeat indicator 2 Always 0 Source ID 30 The ID shall be as defined in 4.4.1 Spare 2 Always 0 Application identifier 16 DAC = 995, FI
18、= 9 Received AIS-SART ID 30 ID of received active AIS-SART RSSI level 8 RSSI level of received active AIS-SART; 127 to +30 dBmin binary Spare 2 Not used. Shall be set to zero. Reserved for future use Number of bits 96 Occupies one slot 4.4.4 Configuration parameters 4.4.4.1 Basic system parameters (
19、See 6.1.1, 6.2.2) The configurable parameters are given in Table 9. 25 DIN EN 62320-3:2015-11 EN 62320-3:2015 Table 9 Configurable parameters Parameter Field Remark Identification User ID The ID shall be as defined in 4.4.1. Used as Source ID for identification messages (see 4.4.2) and as Destinatio
20、n ID for VDL configuration. Primary position source 0 = internal GNSS The average GNSS position shall be stored as a fallback in case of GNSS drop out. 1 = Surveyed position Surveyed Latitude Resolution: 1/10 000 min Default: 91 Position Surveyed Longitude Resolution: 1/10 000 min Default: 181 UTC m
21、inute MM of frame Start slot Channel A 02249 Interval to next transmission Slot interval 0 = no transmission (Default) Maximum 135 000 slots (1 hour) Note that if the interval is set to 0 the disable/enable repeater parameter is also set to disabled (0). Own identification report Access scheme 0 = d
22、epending on reporting interval 1 = FATDMA 2 = ITDMA/RATDMA (RATDMA when interval 7min) 3 = SOTDMA (only if interval = 1 min) Transmit power Transmit power level 0 = high power = 12,5 W or as defined by the manufacturer. 1 = low power = 1 W or as defined by the manufacturer. 2 .9 as defined by the ma
23、nufacturer (optional) Channel A Channels Channel B Channel number according to Recommendation ITU-R M.1084 Setting the channel number “0” disables the transmission on the channel(s). Encryption key 128 bit AES key Default to all zeros. 4.4.4.2 General repetition parameters (See 6.1.1, 6.3.1.3) The general repetition parameters are given in Table 10. 26
