2.2.1 VHF data exchange system channel usage for channel plan A 2.2.1.1 VHF data exchange system between terrestrial stations Automatic identification System (AIS) use channels AIS 1 (161.975 MHz) and AIS 2 – (162.025 MHz), in accordance with Recommendation ; Application Specific Messages (ASM) use channels ASM 1 (channel 2027) and ASM 2 – (channel 2028) are non-navigation ASMs; VDE1 lower legs (channels 1024, 1084, 1025 and 1085) are ship-to-shore VHF data – exchange (VDE); VDE1 upper legs (channels 2024, 2084, 2025 and 2085) are shore-to-ship and ship-to-ship – VDE. 2.2.1.2 VHF data exchange system between satellites and terrestrial stations AIS 1 (161.975 MHz) and AIS 2 (162.025 MHz) are used as uplinks for receiving AIS – messages by satellite; SAT up1 (channel 2027) and SAT up2 (channel 2028) are used for receiving ASM by – satellite; SAT up3 (channels 1024, 1084, 1025, 1085, 1026 and 1086) is a ship-to-satellite VDE – uplink; SAT Downlink (channels 2024, 2084, 2025, 2085, 2026 and 2086) is the satellite-to-ship – VDE downlink. 2.2.2 Technical characteristics 2.2.2.1 ShipborneVHF date exchange system receivers are protected As in AIS, shipborne VDES receivers are on the upper legs of RR Appendix 18, 4.6 MHz above the lower legs, which facilitates protection by filtering from receiver blocking by ships VHF radios. 2.2.2.2 Satellite downlink is optimized The satellite downlink power is spread over 6 channels to minimize interference to terrestrial services and to maximize reception by ship VDES stations. 2.2.2.3 VDE1 uses both legs of the duplex channels Full channel capacity is utilized for the duplex channels in VDE1 by using the lower legs for ship-to-shore and the upper legs for shore-to-ship and ship-to-ship digital messaging. 2.3 Channel plan B
2.2.1 VHF data exchange system channel usage for channel plan A 2.2.1.1 VHF data exchange system between terrestrial stations – Automatic identification System (AIS) use channels AIS 1 (161.975 MHz) and AIS 2 (162.025 MHz), in accordance with Recommendation ; – Application Specific Messages (ASM) use channels ASM 1 (channel 2027) and ASM 2 (channel 2028) are non-navigation ASMs; – VDE1 lower legs (channels 1024, 1084, 1025 and 1085) are ship-to-shore VHF data exchange (VDE); – VDE1 upper legs (channels 2024, 2084, 2025 and 2085) are shore-to-ship and ship-to-ship VDE. 2.2.1.2 VHF data exchange system between satellites and terrestrial stations – AIS 1 (161.975 MHz) and AIS 2 (162.025 MHz) are used as uplinks for receiving AIS messages by satellite; – SAT up1 (channel 2027) and SAT up2 (channel 2028) are used for receiving ASM by satellite; – SAT up3 (channels 1024, 1084, 1025, 1085, 1026 and 1086) is a ship-to-satellite VDE uplink; – SAT Downlink (channels 2024, 2084, 2025, 2085, 2026 and 2086) is the satellite-to-ship VDE downlink. 2.2.2 Technical characteristics 2.2.2.1 ShipborneVHF date exchange system receivers are protected As in AIS, shipborne VDES receivers are on the upper legs of RR Appendix 18, 4.6 MHz above the lower legs, which facilitates protection by filtering from receiver blocking by ships VHF radios. 2.2.2.2 Satellite downlink is optimized The satellite downlink power is spread over 6 channels to minimize interference to terrestrial services and to maximize reception by ship VDES stations. 2.2.2.3 VDE1 uses both legs of the duplex channels Full channel capacity is utilized for the duplex channels in VDE1 by using the lower legs for ship-to-shore and the upper legs for shore-to-ship and ship-to-ship digital messaging. 2.3 Channel plan B
R-REP-M.2371-2015-MSW-E.docx