TABLE A2-9 Modified packet bit structure for satellite uplink ASM message with SCTDMA Slot composition Bits Notes Carrier sense period 56 Not transmitting (2 917 µs, equivalent to 56 bits) Ramp up 16 Standard Pre training sequence 44 0011 (repeat for 44 bits) Training sequence 27 Standard Signal information 7 Decoded from Hamming (7,4) 0000 not coding – 0001 1/2 coding – 0010 3/4 coding – 0011 5/6 coding – Data length 10 Default: (198) encoded data and CRC; “0011000110” Without encoding:166 bits Data field 166 With encoding: varies according to coding rate defined in the Signal Information field Without encoding: 32 bits; CRC 32 With encoding: varies according to coding rate defined in the Signal Information Only the data length and data field are included in the CRC Long-range ASM 154 Synch jitter (mobile station) = 6 bits receiving system buffer Synch jitter (mobile/satellite) = 2 bits Propagation time delay difference = 144 bits Spare = 2 bits Total 512 Maximum 512 bits for 19.2 QPSK π/4 6.2 Transmitting the satellite uplink broadcast message The satellite uplink ASM broadcast message should be transmitted only on ASM channels and not on the following channels: 75, 76, AIS 1, AIS 2 or regional channels. 3 Technical characteristics of VDE-terrestrial in the maritime mobile band 1 Introduction This describes the characteristics of the terrestrial VDES. It contains a description of the different protocols according to the OSI layer model and recommends implementation details for each layer. Data transmission is made in the VHF maritime mobile band. Data transmissions are made within the spectrum allocated for the VDE1-A and VDE1- B. The spectrum may be used as 25 kHz, 50 kHz or 100 kHz channels. The system should use TDMA techniques in a synchronized manner.
TABLE A2-9 Modified packet bit structure for satellite uplink ASM message with SCTDMA Slot composition Bits Notes Carrier sense period 56 Not transmitting (2 917 µs, equivalent to 56 bits) Ramp up 16 Standard Pre training sequence 44 0011 (repeat for 44 bits) Training sequence 27 Standard Signal information 7 Decoded from Hamming (7,4) 0000 – not coding 0001 – 1/2 coding 0010 – 3/4 coding 0011 – 5/6 coding Data length 10 Default: “0011000110” (198) encoded data and CRC; Data field 166 Without encoding:166 bits With encoding: varies according to coding rate defined in the Signal Information field CRC 32 Without encoding: 32 bits; With encoding: varies according to coding rate defined in the Signal Information Only the data length and data field are included in the CRC Long-range ASM receiving system buffer 154 Synch jitter (mobile station) = 6 bits Synch jitter (mobile/satellite) = 2 bits Propagation time delay difference = 144 bits Spare = 2 bits Total 512 Maximum 512 bits for 19.2 π/4 QPSK 6.2 Transmitting the satellite uplink broadcast message The satellite uplink ASM broadcast message should be transmitted only on ASM channels and not on the following channels: 75, 76, AIS 1, AIS 2 or regional channels. 3 Technical characteristics of VDE-terrestrial in the maritime mobile band 1 Introduction This describes the characteristics of the terrestrial VDES. It contains a description of the different protocols according to the OSI layer model and recommends implementation details for each layer. Data transmission is made in the VHF maritime mobile band. Data transmissions are made within the spectrum allocated for the VDE1-A and VDE1- B. The spectrum may be used as 25 kHz, 50 kHz or 100 kHz channels. The system should use TDMA techniques in a synchronized manner.
R12-SG05-RP-1007!!MSW-E.docx