Future Generation of AIS Considers Integration of AIS and VDE. TEXAS V Workshop Canadian Embassy, Washington DC 7-8 November 2012

Transcription

1 Future Generation of AIS Considers Integration of AIS and VDE TEXAS V Workshop Canadian Embassy, Washington DC 7-8 November

2 Rationale for the Integration of AIS and VDE (VHF Data Exchange) Protects the integrity of the AIS VDL (VHF Data Link) The AIS (as a SOLAS requirement) was intended primarily for Navigation Safety/Collision Avoidance. Increased use of AIS Application-Specific Messages (ASM) and other AIS applications and devices competes with this main purpose. Increases the loading capacity of the AIS VDL Future AIS overload is anticipated as AIS applications, equipment types and installations increase. The AIS VDL can safely support the increased loading if non-safety-related AIS communications are moved to new channels (VDE). Enhances data communications and spectrum efficiency Designating new channels for VDE will provide higher data rates (up to 32X) than AIS, e.g., for use in e-navigation. The VDE network protocol is optimized for data communications (vs. AIS for navigation) so that each VDE message is transmitted with a very high confidence of reception. Integration with AIS also benefits VDE by automatically identifying and locating ship and shore stations. Uses WRC -12/15/18 provisions for additional frequencies 2

3 APPENDIX 18 (REV.WRC-12) Table of transmitting frequencies in the VHF maritime mobile band (See Article 52) MOD NOTE A For assistance in understanding the Table, see Notes a) to z) below. (WRC-12) MOD NOTE B The Table below defines the channel numbering for maritime VHF communications based on 25 khz channel spacing and use of several duplex channels. The channel numbering and the conversion of two-frequency channels for single-frequency operation shall be in accordance with Recommendation ITU-R M Annex 4, Tables 1 and 3. The Table below also describes the harmonized channels where the digital technologies defined in the most recent version of Recommendation ITU-R M.1842 could be deployed. (WRC-12) MOD Channel designator Notes From ship stations Transmitting frequencies (MHz) From coast stations Intership Port operations and ship movement Single frequency Two frequency Public correspondence 60 m) x x x 01 m) x x x 61 m) x x x 02 m) x x x 62 m) x x x 03 m) x x x 63 m) x x x 04 m) x x x 64 m) x x x 05 m) x x x 65 m) x x x 06 f) x 2006 r) m) x x x 07 m) x x x 67 h) x x x

4 Channel designator Notes From ship stations Transmitting frequencies (MHz) From coast stations Intership Port operations and ship movement Single frequency x 09 i) x x x x 10 h), q) x x Two frequency Public correspondence 70 f), j) Digital selective calling for distress, safety and calling 11 q) x x x 72 i) x 13 k) x x 73 h), i) x x x x 15 g) x x 75 n), s) x 16 f) DISTRESS, SAFETY AND CALLING 76 n), s) x 17 g) x x x 18 m) x x x 78 t), u), v) x x x x x 19 t), u), v) x x x x x 79 t), u), v) x x x x x 20 t), u), v) x x x x x 80 w), y) x x x 21 w), y) x x x 81 w), y) x x x 22 w), y) x x x

5 Channel designator Notes From ship stations Transmitting frequencies (MHz) From coast stations Intership Port operations and ship movement Single frequency Two frequency Public correspondence 82 w), x), y) x x x 23 w), x), y) x x x w), x), y) x x x w), ww), x), y) w), ww), x), y) w), ww), x), y) w), ww), x), y) w), ww), x), y) w), ww), x), y) x x x x x x x x x x x x x x x x x x 27 z) x x 87 z) x 28 z) x x 88 z) x AIS 1 f), l), p) AIS 2 f), l), p)

6 Notes referring to the Table General notes MOD c) The channels of the present Appendix, with the exception of channels 06, 13, 15, 16, 17, 70, 75 and 76, may be used for direct-printing telegraphy and data transmission, subject to special arrangement between interested and affected administrations. (WRC-12) MOD e) Administrations may apply 12.5 khz channel interleaving on a non-interference basis to 25 khz channels, in accordance with the most recent version of Recommendation ITU-R M.1084, provided: it shall not affect the 25 khz channels of the present Appendix maritime mobile distress and safety, automatic identification system (AIS), and data exchange frequencies, especially the channels 06, 13, 15, 16, 17, 70, AIS 1 and AIS 2, nor the technical characteristics set forth in Recommendation ITU-R M for those channels; implementation of 12.5 khz channel interleaving and consequential national requirements shall be subject to coordination with affected administrations. (WRC-12) Specific notes MOD n) With the exception of AIS, the use of these channels (75 and 76) should be restricted to navigation-related communications only and all precautions should be taken to avoid harmful interference to channel 16, by limiting the output power to 1 W. (WRC-12) SUP o) ADD r) In the maritime mobile service, this frequency is reserved for experimental use for future applications or systems (e.g. new AIS applications, man over board systems, etc.). If authorized by administrations for experimental use, the operation shall not cause harmful interference to, or claim protection from, stations operating in the fixed and mobile services. (WRC-12) ADD s) Channels 75 and 76 are also allocated to the mobile-satellite service (Earth-to-space) for the reception of long-range AIS broadcast messages from ships (Message 27; see the most recent version of Recommendation ITU-R M.1371). (WRC-12) ADD t) Until 1 January 2017, in Regions 1 and 3, the existing duplex channels 78, 19, 79 and 20 can continue to be assigned. These channels may be operated as single-frequency channels, subject to coordination with affected administrations. From that date, these channels shall only be assigned as single-frequency channels. However, existing duplex channel assignments may be preserved for coast stations and retained for vessels, subject to coordination with affected administrations. (WRC-12)

7 ADD u) In Region 2, these channels may be operated as single-frequency channels, subject to coordination with affected administrations. (WRC-12) ADD v) After 1 January 2017, in the Netherlands, these channels may continue to be operated as duplex frequency channels, subject to coordination with affected administrations. (WRC-12) ADD w) In Regions 1 and 3: Until 1 January 2017, the frequency bands MHz and MHz (corresponding to channels: 80, 21, 81, 22, 82, 23, 83, 24, 84, 25, 85, 26, 86) may be used for new technologies, subject to coordination with affected administrations. Stations using these channels or frequency bands for new technologies shall not cause harmful interference to, or claim protection from, other stations operating in accordance with Article 5. From 1 January 2017, the frequency bands MHz and MHz (corresponding to channels: 80, 21, 81, 22, 82, 23, 83, 24, 84, 25, 85, 26, 86) are identified for the utilization of the digital systems described in the most recent version of Recommendation ITU-R M These frequency bands could also be used for analogue modulation described in the most recent version of Recommendation ITU-R M.1084 by an administration that wishes to do so, subject to not claiming protection from other stations in the maritime mobile service using digitally modulated emissions and subject to coordination with affected administrations. (WRC-12) ADD ww) In Region 2, the frequency bands and MHz (corresponding to channels: 24, 84, 25, 85, 26 and 86) are designated for digitally modulated emissions in accordance with the most recent version of Recommendation ITU-R M (WRC-12) ADD x) From 1 January 2017, in Angola, Botswana, Lesotho, Madagascar, Malawi, Mauritius, Mozambique, Namibia, Democratic Republic of the Congo, Seychelles, South Africa, Swaziland, Tanzania, Zambia and Zimbabwe, the frequency bands and MHz (corresponding to channels: 82, 23, 83, 24, 84, 25, 85, 26 and 86) are designated for digitally modulated emissions. From 1 January 2017, in China, the frequency bands and MHz (corresponding to channels: 23, 83, 24, 84, 25, 85, 26 and 86) are designated for digitally modulated emissions. (WRC-12) ADD y) These channels may be operated as single or duplex frequency channels, subject to coordination with affected administrations. (WRC-12) ADD z) These channels may be used for possible testing of future AIS applications without causing harmful interference to, or claiming protection from, existing applications and stations operating in the fixed and mobile services. (WRC-12)

8 Example of Integrated AIS and VDE Based on: WRC-12 decisions, Region 2 (minimum set, globally-available channels) WRC-15 Agenda Item 1.16 (Resolution 360) for AIS and VDE Approved Recommendations for AIS & VDE: ITU-R M.1371 & 1842 Table 1 NOTES: a) Can be used separately as 25 khz channels or as one 50kHz channel. b) These channels may be considered for satellite downlink. VDE NOTE: These four channels are combined as one 100kHz channel. AIS + VDE NOTE: Channels 27 and 28 are used as simplex on the upper legs (B-side), since the AIS is a simplex system. 24A/B 84A/B 25A/B 85A/B 26A/B 86A/B 27B AIS 1 28B AIS 2 NOTE: Since this comprises a contiguous set of frequencies (RR Appendix 18), it can be protected by the frequency-selective receiver filter shown in Figure 1. 3

9 Example Table of Channels and Transmitting Frequencies Used for AIS and VDE Table 2 Channel Number in Appendix 18 Transmitting frequencies (MHz) for ship and coast stations Ship stations (ship-shore) Ship stations (long range AIS) Coast stations Ship stations (ship-ship) Satellite downlink* AIS AIS (AIS 3) (long range AIS) (ships are Tx only) N/A 76 (AIS 4) (long range AIS) (ships are Tx only) N/A 27B (VDE 1) (27B) (27B) 28B (VDE 2) (28B) (28B) 24 (VDE 3) (24A) (24B) 84 (VDE 4) (84A) (84B) 24/84 (VDE 5)* 50 khz channel (24/84, A-side, merged) 50 khz channel* (24/84, B-side, merged) 25/85/26/86 (VDE 6) 100 khz channel (25/85/26/86, A-side, merged) (25A) (25B) (85A) (85B) (26A) (26B) (86A) (86B) 100 khz channel (25/85/26/86, B-side, merged) 4

10 ITU Standard and Digital Modulation Comparison of AIS and VDE Data Transfer Methods on 25 khz Channels AIS1 and AIS2 (25 khz Channels) ITU-R M.1371 GMSK Table 3 ITU-R M.1842 Annex 1 π/4 DQPSK VDE Data Transfer Methods For 25 khz Channels ITU-R M.1842 Annex 1 π/8 D8PSK En v3.2.1 Section 5.11* 8-OFDM + 16-QAM Data Rate 9.6Kbps (1X) 28.8Kbps (3X) 43.2Kbps (4X) 76.8Kbps (8X) Sensitivity -107dBm -107dBm -107dBm -107dBm Co-channel rejection 10dB 19dB 25dB 19dB (CCR) Adjacent channel 70dB 70dB 70dB 70dB rejection (ACR) AIS Message types 1, 2, 3, 5, 18, 19 6, 7, 8,12,13,14 6, 7, 8,12,13,14 6, 7, 8,12,13,14 Rationale Optimum choice for recurring position reports in a shipship navigation safety environment. Provides high (3X) data transmission. Inferior CCR (+9dB) and range discrimination. Provides high (4X) data transmission. Inferior CCR (+15dB) and range discrimination. Highest (8X) data rate for a 25kHz channel (compress multi-slot messages to a single slot). * This standard should also be considered for high data rate and robustness. 5

11 Comparison of Data Transfer Methods for VDE by WRC-12 (refers to Rec. ITU-R M.1842) Table 4 VDE Data Transfer Methods For 25 khz Channels VDE Data Transfer Methods For 50 khz and 100 khz Channels ITU Standard and Digital Modulation ITU-R M.1842 Annex 1 π/4 DQPSK or π/8 D8PSK ITU-R M.1842 Annex 3 16-OFDM + 16-QAM ITU-R M.1842 Annex 4 32-OFDM + 16-QAM Data Rate 28.8Kbps (3X) or 43.2Kbps (4X) 153.6Kbps (16X) 307.2Kbps (32X) Sensitivity -107dBm (ship/shore stations) -103dBm (ship stations) -98dBm (ship stations) Co-channel rejection 19dB or 25dB 19dB 19dB (CCR) Adjacent channel 70dB 70dB 70dB rejection (ACR) Message types AIS 6, 7, 8,12,13,14 and ASM VDE messages TBD VDE messages TBD Rationale Provides higher (3X or 4X) data transmission than AIS. Inferior CCR (+9dB or +15dB) and range discrimination compared to AIS. Provides much higher (16X) data transmission than AIS. Inferior CCR (+9dB) and range discrimination compared to AIS. Provides much higher (32X) data transmission than AIS. Inferior CCR (+9dB) and range discrimination compared to AIS. 6

12 Architecture of Integrated AIS/VDE System Functional Block Diagram Figure 1 VHF antenna T/R Switch AIS-VDE Multi-function Transmitter AIS/VDE Receiver 4-channels (SDR)* AIS 1, AIS 2, VDE 1, VDE 2 ( ) Bandpass Filter ( MHz) VDE Receiver 4-channels (SDR)* VDE 3, VDE 4, VDE 5, VDE 6 ( ) AIS-VDE Multi-function Tx/Rx Processer GPS antenna PI/ MKD * 4-channel SDR (software defined radio) technology is used in some new AIS designs. 7

13 Architecture of Integrated AIS/VDE AIS/VDE SDR Receiver Functional Block Diagram Figure 2 Receive channel 1 VDE 1 ( MHz) From Bandpass Filter Receive channel 2 AIS 1 ( MHz) Receive channel 3 VDE 2 ( MHz) 4-channel AIS/VDE Message Receiver (SDR)* To Tx/Rx Multi- Function Processer Receive channel 4 AIS 2 ( MHz) * This 4-channel AIS/VDE SDR receiver has been implemented in some new AIS designs. 8

14 Architecture of Integrated AIS/VDE VDE SDR Receiver Functional Block Diagram Figure 3 Receive channel 1 VDE 3 ( MHz) From Bandpass Filter Receive channel 2 VDE 4 ( MHz) Receive channel 3 VDE 5 (50 khz channel) 4-channel VDE Message Receiver (SDR)* To Tx/Rx Multi- Function Processer Receive channel 4 VDE 6 (100 khz channel) * This 4-channel VDE SDR receiver is similar to the AIS/VDE SDR receiver in Figure 2. 9

15 Rationale for the Selection and Use of Frequencies 1. Protect the integrity of the AIS/VDE shipborne receivers AIS and VDE use efficient SDR receivers (refer to Figure 1) on the upper legs (B-side) of the channels, thus protected from the ships VHF radio transmitters on the lower legs (A-side) by a Bandpass filter. 2. Duplex channels are used conventionally for ship-shore In ship-shore mode, VDE is transmitted by ships on the lower legs (Aside) and by shore stations on the upper legs (B-side). This arrangement plus the higher data rate for VDE (preferably kbps, per Table 4) minimizes potential conflicts between AIS and VDE. 3. Duplex channels are used in simplex mode for ship-ship In ship-ship mode, VDE is transmitted by ships on the upper legs (Bside), because the VDE ships receivers are on the B-side. The higher data rate (307.2 kbps) is preferred to shorten (by 32X) the transmission time and minimize the potential conflicts between AIS and VDE. 10

16 Rationale for the Selection and Use of Frequencies (continued) 4. Future satellite downlink is possible Since VDE communications ship-ship and ship-shore will prefer the higher data rate (307.2 kbps), the 50 khz channel at kbps (Table 4) could be made available for a future satellite downlink. 5. Ship-shore use of duplex channels for VDE is practical Shore stations operating both AIS and VDE will prefer the higher data rate (307.2 kbps) for VDE to minimize the transmission time, and since their VDE transmissions are not time-critical, they can defer to the AIS. 6. AIS and VDE channels are frequency-contiguous The AIS and VDE channels (Table 2) are a frequency-contiguous block in Appendix 18 of the Radio Regulations. This configuration provides the maximum spectrum efficiency, highest equipment performance, minimum implementation cost and complexity (facilitates use of SDR technology, refer to Figures 1-3) and minimum regulatory impact. 11

17 Schedule of Actions and Progress Reports The schedule below considers the need to support the WRC-15/18 Agenda Items and the necessary reports to ITU and the Joint IMO/ITU Expert Group: Table 5 Progress Milestone 1. Administrations provide an experimental working environment for test and evaluation (e.g., RTCM SC123 in the US, and Mona Lisa in Europe) Date November Workshop Session 1 (functional requirements for Next-generation AIS ) December Begin test/evaluation in the working environment January IALA ENAV WG3+WG4 meeting (draft selection and use of frequencies) February Progress report to IALA ENAV with technical conclusions. Draft Report to ITU WP5B (for Nov 2013 meeting) on WRC-15 AI 1.16: selection and use of frequencies, sharing and compatibility studies in the band (App 18) September Workshop Session 2 (technical requirements for Next-generation AIS ) December IALA ENAV WG3+WG4 meeting (draft technical standard) February Progress report to IALA ENAV. Draft Report to ITU WP5B (for Nov 2014 September 2014 meeting) on WRC-15 AI 1.16: working document toward PDNR 9. Workshop Session 3 (draft performance standard for Next-generation AIS ) December Progress report to IALA ENAV. Draft report to ITU WP5B (Nov 2014), final draft performance standard for administrations to submit to ITU for DNR September

18 TABLE OF VHF CHANNELS FOR AIS/VDE/ASM VDE table of frequencies (MHz) VDE Ship transmit Ship received Can be used separately or as To be combined as a 100 khz channel one 50kHz channel. NOTE - The VHF channels shown above are a contiguous set in Appendix 18. They comprise a contiguous frequency block, and thus are amenable to protection by a single selective filter in the receiver. AIS and ASM table of frequencies (MHz) 2027 AIS AIS ASM 1 ASM 2 NOTE - The VHF channels shown above are a contiguous set in Appendix 18. They comprise a contiguous frequency block, and thus are amenable to protection by a single selective filter in the receiver. Long-range AIS broadcast messages from ships Satellite broadcasting to ship (MHz) And/or NOTE - These VHF channels are a first tentative These 2 channels could be to identify a satellite broadcasting frequency combined for satellite band to the ship. The content of this broadcasting purpose. broadcasting emission has to be determined.

19 Table describing the possible use of Appendix 18 channels and frequencies for AIS, ASM, VDE and satellite broadcasting Channel number in Appendix 18 Transmitting frequencies (MHz) for ship and coast stations Ship stations (ship-shore) Ship stations (long range AIS) Coast stations Ship stations (ship-ship) Satellite broadcasting to ship* AIS AIS (long range AIS) (ships are Tx only) N/A 76 (long range AIS) (ships are Tx only) N/A 2027 (ASM 1) (2027) (2027) 2028 (ASM 2) (2028) (2028) 24 (VDE 1) MODE A (1024) (2024) 84 (VDE 2) MODE A (1084) (2084) 24/84 (VDE 3) or (SAT5) MODE B 50 khz channel (1024/1084, merged) 50 khz channel (2024/2084, merged)* *Could be used for satellite broadcasting 25/85/26/86 (VDE 4) 100 khz channel (25/85/26/86, lower legs, merged) 100 khz channel (25/85/26/86, upper legs, merged) (1025) (1085) (1026) (1086) (2025) (2085) (2026) (2086) 1027 SAT 1 N/A (ships are Rx only) * (1027) 87 SAT 2 N/A (ships are Rx only) * (87) 1028 SAT 3 N/A (ships are Rx only) * (1028) 88 SAT 4 N/A (ships are Rx only) * (88)

20 Plan for AIS and VDE Communications 1 Existing AIS only Satellite detection AIS AIS AIS AIS AIS2 Ship transmit channels for VDE using ITU1842 Approx. 4.6 MHz separation AIS-VDE ship receiving bandwidth

21 Plan for AIS and VDE Communications 2 AIS and SOTDMA VDE (ASM applications) Ship-Ship VDE using SOTDMA AIS AIS Shore-Ship &Ship- Shore VDE using SOTDMA AIS AIS2 Ship transmit channels for VDE using ITU1842 Approx. 4.6 MHz separation AIS-VDE ship receiving bandwidth

22 Plan for AIS and VDE Communications 3 VDE using ITU-R M.1842 Shore-to-Ship VDE using ITU1842 Ship-to-Shore VDE using ITU1842 Ship-Ship VDE using ITU AIS AIS2 Ship transmit channels for VDE using ITU1842 Approx. 4.6 MHz separation AIS-VDE ship receiving bandwidth

23 Plan for AIS and VDE Communications 4 All Shore-to-Ship VDE using ITU1842 Satellite detection AIS Satellite broadcasting Ship-to-Shore VDE using ITU1842 Ship-Ship VDE using ITU1842 AIS AIS Shore-Ship &Ship- Shore VDE using SOTDMA Ship-Ship VDE using SOTDMA AIS AIS2 VDE1 VDE2 VDE1 VDE2 ASM1 ASM2 VDE3 VDE4 SAT1 SAT2 SAT3 SAT4 VDE3 VDE4 SAT5 Ship transmit channels for VDE using ITU1842 Ship receiving CH for Sat broadcasting 4.6 MHz separation AIS-VDE ship receiving bandwidth