Transcript e-Navigation & Communications

Novel Maritime Communications
User Requirements
and
e-Navigation
Fritz Bekkadal, Kay E. Fjørtoft, Ørnulf J. Rødseth
MARINTEK
Nornav ”e-Navigation”, Oslo 16-17.10.2007
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 “e-Navigation is the harmonized creation,
collection, integration, exchange and presentation
of maritime information on board and ashore by
electronic means to enhance berth-to-berth navigation
and related services, for safety and security at sea and
protection of the marine environment.” [IMO’s NAV
subcommittee]
 …which is judged to be unachievable without an
encompassing implementation of highly developed
communication means !
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e-Navigation & Communications
 At the 1st meeting of the IALA e-Navigation Committee, three
fundamental elements were identified that should be in place before
e-Navigation could be introduced. These are:
1. Electronic Navigation Chart (ENC) coverage of all navigational areas
2. A robust electronic position-fixing system (with redundancy)
3. An agreed infrastructure of communications to link ship and shore
e-Navigation Requirements
An infrastructure providing authorized seamless information transfer onboard
ship, between ships, between ship and shore and between shore authorities
and other parties with many related benefits, including a reduction of single
person error…
e-Navigation = Information + Communication + Presentation

___________________________________
Highly developed Digital Communication
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Present maritime digital communication
NAVTEX
HF, MF
300 bps
DSC
VHF
1.2 kbps
Loran-C
Access via NMEA 0183
4.8 kbps
AIS
VHF
9.6 kbps
GPS
Access via NMEA 0183
4.8 kbps
LRIT
Short messages, Satellite
100 bits/hour
EPIRB
Short messages, Satellite
100 bits/hour
SSAS
Short messages, Satellite
100 bits/day
SafetyNET
NAVTEX over Inmarsat
100 messages /day
Some ships have digital data links via Satellite
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How to implement e-Navigation ?
 Use of satellite communications ?
 Perceived as expensive by owners (LRIT discussions!)
 Bandwidth limitations
 Use of existing maritime infrastructure (DSC and AIS) ?
 Insufficient bandwidth !
 Short messaging over GALILEO (or other similar systems) ?
 Insufficient bandwidth !
 May not be available !
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Use of terrestrial communication systems !
 Highest communication requirements near shore and port
 Most shipping lanes are near the coast
 Relatively easy and low cost to build infrastructure
 Relatively low cost user equipment
 May also cover some arctic regions, e.g., north-east
and/or north-west passage
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Bandwidth requirements - services
 Ship clearance, reporting
 NAVTEX, notice to mariners, update of charts (Broadcast)
 Quality controlled AIS targets from VTS (Broadcast) ?
 Remote pilot guidance ?
 Remote (equipment) surveillance, diagnostics and (repair) guidance ?
 …etc …
Requirements per ship (except Broadcast):
Probably in the order of 100 kByte/day !
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Key eNavigation communication requirements
 Sufficient bandwidth, i.e. data capacity
 Sufficient robustness, e.g. signal strength and quality,
resistance to interference…
 Satisfactory security, e.g. encryption and authentication
 Scalability and growth potential
 Autonomous acquisition and mode switching, i.e.
minimum mariner involvement needed
 Common messaging formats
 Automated report generation
 Global coverage,
which could be achieved with more than one technology…
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Possible (terrestrial) solutions






WiMAX
WiFi/WLAN
GSM/EDGE/UMTS 3G/LTE
Digital VHF (D-VHF, VDL…)
CDMA 450 (ref. ICE)
Reclaimed VHF/UHF TV-bands ?
 VHF/UHF-WiMAX (?)
 Hybrid wireless solutions (with seamless handover and
roaming)
 Other…
This requires rapid standardization,
if it is going to be used in e-Navigation !
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The MarCom Project
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The MarCom Consortium
Project information:
 Duration:
2007-2010
 Budget:
 Total:  32 MNOK
 Financial support from
the Norwegian Research
Council’s MAROFF
program:  15 MNOK
 Project Administrator:
Mobikom
 Project Manager:
MARINTEK
 28 partners
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Application areas
The High North
Environment
Long-Range
Technical Operations,
Reporting
Short messaging
Safety, Surveillance,
Aids to Navigation
Safety at Sea (SAR)
Service Platform
On-board LAN
Broadband at Sea
Communications
vessel-Land
IO, Safety, SAR,
Infortainment, Critical
Operations
©SAAB Transpondertekonologi
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Novel Maritime Communications
Technological Opportunities
and Challenges
Fritz Bekkadal
MARINTEK
Nornav ”e-Navigation”, Oslo 16-17.10.2007
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 Mainland
area:
(58°N - 71°N,
5°E - 31°E):
323 758 km²
 EEZ:
878 575 km²
 Svalbard
protection
zone:
803 993 km²
 Jan Mayen
protection
zone:
296 611 km²
  2 mill. km²
 Straight coast
baseline:
2 532 km
 Continental
coastline:
25 148 km
Source: ACIA
Norway's large territory and economic zone makes radio technology
crucial to the endurance of our environment, industry and business !
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MarCom User Communities
 Commercial
 Shipping vessels, cruise ships, high-speed
crafts, personal vessels, fishing vessels,
offshore installations (incl. search and supply
utilities), aquaculture installations (incl.
transportation facilities ) …
 Scientific
 Research vessels, unattended buoy platforms
(w/sensors: weather, environment…),
autonomous underwater utilities, unattended
offshore and onshore observation sites…
 Homeland Security
 Coast Guard cutters, deployable pursuit boats,
possibly Navy and first responders near the
coast…
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Norwegian coastal waters
User Platforms:
 Maritime/Marine
 Boats/ships ranging from small personal
watercraft to cruise ship size for all user types:

Shipping vessels, research vessels, yachts,
fishing vessels, Coast Guard cutters etc.
 Offshore oil/gas production installations,
searching rigs/vessels, supply vessels…
 Aquaculture installations, supply and service
vessels…
 Buoys ranging from small (<1 m in diameter) to
very large (up to 25 m in diameter), both freefloating and moored…
 Land-based
The major part of our
coastal traffic takes
place within 20 nm
(< 40 km)
 Shore-based observation towers and other
facilities, Research centers, Surveillance
facilities, First Responder Agency Headquarters,
Users of personal communication equipment
(laptops, PDAs etc.) near the coast…
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Opportunities
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IO: ”Integrated Operations”
Opportunities Offshore:
IO within oil (and aquaculture…)
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R&D Focus Areas
A. Communication vessel  land
B. Generic scaleable service platform
 Supplemented by a ”Smart Router”
[”AMCA” (”Agile MarCom Adapter”)]
C. Optimized maritime mobile LAN designs
MarCom will all together address the emerging convergence
between Communications, Surveillance and Navigation
(ref. e-Navigation and e-Maritime)
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R&D Arena Framework
GNSS
A
B
B
C
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Communication Challenges
 Extending coverage and range at sea for both in-use and novel
terrestrial wireless systems/technologies, e.g.:
 WiMAX
 WiFi/WLAN
 GSM/EDGE/UMTS 3G/LTE
 Digital VHF (D-VHF, VDL…)
 CDMA 450 (ref. Ice)
 Reclaimed VHF/UHF TV-bands ?
 Finding appropriate SatCom solutions to complement the terrestrial
ones, mainly beyond their coverage, e.g.:
 BGAN (Inmarsat)
 VSAT; DVD-RCS(/S2)
 Molniya orbits (?)
 Obtaining seamless and continuous handover and roaming within
and between the pertinent systems
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Terrestrial Communication Technologies
Technology/
System
WiFi/WLAN
(IEEE802.11)
GSM/GPRS/
EDGE
UMTS
CDMA 450
(Ref.”ICE”)
VHF/BIIS
DAB
(”Digital Audio
Broadcast”)
WiMAX
(IEEE 802.16)
Digital VHF
(VHF Digital Data)
VHF/UHF
”TV-band” (?):
174–230 MHz
470–862 MHz
Weaknesses
Strengths
Bandwidth/
Capacity
Comments
Limited range (20-200 m)
Wireless Ethernet for PCs, PDAs etc.
1-50 Mbps
Wireless Ethernet for PCs, PDAs etc.
Used somewhat in ports, especially for
leisure boats
Limited range,
Comparatively high cost
Existing GSM technology.
Reasonable range.
GSM:
9.6 kbps
GPRS: 56-172 kbps
EDGE: 56-172 kbps
”2. - 2.5” generation mobile
communications systems (2G – 2.5G)
Limited centralized coverage.
Expensive to obtain nationwide
Coverage.
Reasonable bandwidth
”Standard” mobile phone technology
< 2 Mbps
3rd generation (3G) mobile system. Hardly
suited for the maritime market, especially
due to limited coverage and range.
Relatively small total bandwidth
per base station. Unproven signal
quality in difficult environments.
Reasonable number of base stations
being deployed.
Reasonable range.
< 2 Mbps
Utilizes ”old” NMT 450 frequencies
(453-457,5 / 463-467,5 MHz)
Very limited capacity.
Standard and readily available
equipment. Long range.
1 200 bps
Used ao. by the taxi business.
Hardly relevant for the maritime market.
Unidirectional broadcast operation
only.
Inexpensive receivers.
Reasonable bandwidth.
1.7 Mbps
May be interesting for broadcasting general
info., e.g. electronic maps and
meteorological data.
Novel system under roll-out by
several operators in different
areas.
High bandwidth and long range.
International standard (IEEE 802.16).
Robust modulation methods.
10 Mbps per
3.5 MHz channel.
Robust wireless communication system.
Utilizes both licensed and unlicensed
frequency bands.
Unique Norwegian solution.
Limited bandwidth per base
Station.
Very long range (70 nm 130 km).
Excellent coastal coverage.
Steady frequency band (156 MHz).
225 kHz bandwidth per
Channel. Total: 9 channels
(21 kbps/133 kbps)
55 base stations covering the coastline
from Oslo to Kirkenes.
Provides roaming functionality.
Undecided (?)
Vast possibilities !
Adapted WiMAX
Technologies (?)
MarCom contacts with The Norwegian
Post and Telecommunications Authority
(NPT).
WRAN
(IEEE 802.22) (?)
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Evolution of the technologies
- Convergence
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Radio engineering challenges








Radio propagation over sea
Antennas and transceivers
Interference; EMC/EMI
Repeaters
Mobile Multi-hop relay (MMR)
Multi-system switching
Novel communication platforms !
New/reclaimed frequency resources !
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Radio propagation over sea
 Low elevation angles (LOS/nLOS/NLOS)
 Reflections, scattering, refraction and diffraction
of radio waves  Multipath interference
 Over-the-horizon (OTH) coverage (NLOS)
 Radio channel modeling/-estimation:
 Deterministic vs. statistical models
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Example – WiMAX on ferry
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Horizon distance
Rh1
h1
40
35
25
20
15
10
5
10
0
90
80
70
60
50
40
30
20
10
0
0
Rh1 [km]
30
h1 [m]
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Over-the-horizon ?
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Over-the-horizon propagation
(OTH)
 We know signals do propagate beyond the horizon,
and the major mechanisms are:
 Refraction - bending of signals towards ground/sea
 Scattering - from eddies in the air, rain, reflecting surfaces and
objects
 Diffraction - from terrain, objects (floating and fixed), and from
sea waves
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Radio channel modeling
N
Received signal: Sr ( r , t )   ai (r , t )e
j
2 ri

i 0
where a0 (ŕ,t) is the amplitude of the signal transmitted directly along a
straight line between TX and RX, being separated by a distance r0 ,
while the signals following other paths are cause by (space- and
time-dependent) effects, like:
• Reflection (specular and diffuse)
• Refraction
• Diffraction
• ”Ducting”
• ….etc…
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Antennas and transceivers (1)
 Base station antennas
 Standard antennas: One fixed beam
 Electronic steerable antennas, e.g. DBF (”Digital beamforming”):
SW-controlled antennas with adaptive radiation patterns which can
be tailored to the electromagnetic environment (several beams)
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Antennas and transceivers (2)
 Repeater antennas
 DBF/MIMO (?)
 Vessel antennas
 Omnidirectional/Sectorial coverage (?)
 Fixed  electronic steerable (?)

DBF/MIMO (?)
 MIMO (”Multiple-In Multiple-Out”);
Channel estimation based on a combination of signals from M
transmitters (M-In) and N receivers (N-Out) in order to:
 Increase the fading resistance
 Increase the combined radio channels spectral efficiency
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Repeaters (Relay Stations)
 Regenerating repeaters
 Active/passive retransmitting repeaters
RS2
BS
RS1
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Mobile Multi-hop Relay (MMR)- e.g WiMAX
A system enabling mobile stations to communicate with a base station
through intermediate relay stations
 MMR-base station (MMR-BS):
A base station compliant with
amendment IEEE 802.16j to
IEEE Standard 802.16e
 Relay station (RS) Type:
 Fixed relay station (FRS):
Relay:
 Dedicated carrier owned infrastructure
 Tree based topology
 One end of the path is the base station
RS permanently installed at a
fixed location
 Nomadic relay station (NRS):
RS operating from a location
fixed for periods of time
comparable to a user session
 Mobile relay station (MRS):
RS operating while in motion…
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Mesh Networking
 A mixture of fixed and mobile
nodes interconnected via
wireless links to form a multihop ad-hoc network
 A wireless multi-hop ad hoc
network amongst ships,
marine beacons and buoys
 Static and dynamic nodes
 Connected to the terrestrial
networks via land stations at
shore
 A kind of VANET/MANET
(“Vehicular/Mobile Ad Hoc
Network”), with:
 mobility pattern unlike
Mesh:
 Routing by subscriber equipment
 Multiple connections
 Mesh topology
terrestrial VANET, and
 time-varying received signal
quality and wave occlusions
due to sea surface
movements
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Mesh versus Relay
• “Infrastructure” means that an operator provides dedicated equipment providing Mesh or Relay function.
• “Client” means that a user terminal has Mesh or Relay function.
• SS: Subscriber Station, MS: Mobile Station, RS: Relay Station
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©
The MarCom WiCAN Concept
(Wireless Coastal Area Network)
Internet
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Pertinent SatCom Technologies
 BGAN (Inmarsat)
 VSAT; DVD-RCS(/S2)
 Molniya orbits (?)
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BGAN
 BGAN (”Broadband Global Area Network”)
 Inmarsat GEO satellites
 Capacity:
”BGAN offers background internet
speeds (up to) 492 kbps”
Uplink: 300-400 kbps
 Packet and line-switched data
 ”UMTS roaming”
 “User cost competitive to UMTS
international roaming”
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”Novel” VSAT: DVB-RCS(/S2)
 DVB-S (”Digital Video Broadcast – Satellite”):
The most widely used standard for digital broadcasting by satellite
 Downlink: 50 Mbps
 DVD-S2 is the 2nd generation of DVB-S
 Claimed performance gain over DVB-S is around 30% (Downlink:  80 Mbps)
 DVB-RCS (”DVB-Return Channel Satellite”):
Standard for return channel which facilitate bidirectional communications
via satellite
 Broadband communications with high capacity towards user:

Downlink: < 40 Mbps
and with more moderate capacity from user:

Uplink: < 2 Mbps
 Over 100 DVB-RCS systems worldwide - many updated with DVB-S2
 Going mobile with handover from satellite to satellite.
Trials including train, aircraft and vessel-mounted terminals
 Revision end of 2007 !
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Maritim DVB-RCS
Ku-band: 12.5 -18 GHz
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Multisystem switching
 Terrestrial: WiMAX, WiFi, GSM, 3G/4G, D-VHF…
 SatCom
 
 Seamless and continuous transfer:

”Handover” (switching between different base stations within
the same network)


”Media Independent Handover” (MIH) [IEEE 802.21  4G]
”Roaming” (switching between different networks)
[IEEE 802.16g…]
 QoS
 LCR switching
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Ocean areas outside Norway
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Satellite orbits
LEO
MEO
GEO
 LEO: Low Elliptical Orbit
 MEO: Midium Elliptical Orbit
 GEO: Geostationary Orbit
(
Height: 200 - 2000 km)
(
Height: 2.000-GEO,
normally 10.000-20.000 km)
(Height: 35.786 km)
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Covering the High North
Theoretical limit
for GEO satellite
(0o elevation)
5o elevation (El)
with optimum satellite
Practical problems
with standard SatCom
beyond 70o N (< 8o El.)
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Apogeum
Satellite orbits +
Tundra
HEO
Molniya
LEO
MEO
GEO
Perigeum




LEO: Low Elliptical Orbit
MEO: Medium Elliptical Orbit
GEO: Geostationary Orbit
HEO: High Elliptical Orbit
(
Height: 200 - 2000 km)
(
Height: 2.000-GEO, normally: 10.000-20.000 km)
(Height: 35.786 km)
(
Height: 500-50.000 km)
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Molniya orbits
 During the early 1960's Soviet Union aerospace engineers
devised a very clever and practical type of orbit that would
simulate the convenience of a GEO orbit, while at the same
time servicing the extreme northern regions
 The orbit’s inclination is (ideally) 63.45° with respect to the
equatorial plane, and it’s orbital period equals ½ a sidereal day
 During the orbital period of 12 hours the Earth will make ½ a
turn, and thus the apogeum will be at the very same position
relative to earth twice a day
 The Molniya orbits inclinations are such that the effects of apsidal (perihelion)
precession are virtually negligible, thus providing natural orbit preservation in
that respect
 Seen from the Earth a Molniya orbit satellite will thus apparently be in zenit
about 40 000 km above these two positions (at latitude 63.45°) during about 8
hours each day, the perigeum height being only about 1000 km
 2 satellites might consequently provide continuous coverage of the northern
hemisphere, but 3 would be preferred
 Molniya satellite orbits have been used for European communications
partnerships, and at one time was even used for the Moscow-Washington "Hot
Line" between the Soviet Union and the United States.
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Molniya orbit (HEO)
Trondheim
Russian: молния = “lightening”
Ground track of Molniya satellite 3-47 over 6 orbits
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Ground tracks of the 8 operational Molniya satellites (2006)
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Wireless Broadband - Technical Challenges:
Crowded radio spectrum
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Released VHF/UHF TV-bands
 ”The spectral sirloin”
 The frequencies below 1 GHz, and especially the range
200 MHz-1 GHz, is deemed the most valuable we possess
 St.meld. nr. 44 (2002-2003)-Om digitalt bakkenett for fjernsyn
(National assembly white paper on Digital Terrestrial Television - DTT )
 Memo from NPT dated 15.01.2003 to the Ministry of Transport and
Communications: ”Future use of the frequency bands
174–230 MHz and 470–862 MHz”

Alternative to DTT for these frequency bands ?
”A suggestion supported by some is to use these bands for radio
access (Fixed Wireless Access), a technology so far being offered
mostly to the professional market. Roughly speaking it is a point-tomultipoint system, where one transmitter is servicing several receivers,
the actual frequency range being planned for bidirectional
communications”
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USA:
Key Pieces of Licensed and Unlicensed Spectrum
Upper
Low/Mid UNII
Int’l UNII and ISM
Int’l
WCS ISM MMDS
Licensed
New Spectrum
2
3
4
5
GHz
UHF
0.75 - 0.8
Channels 60-69, called the upper 700 MHz, are by congressional
statute to be reclaimed for new services (broadband wireless).
ISM
0.9 - 0.93
Industrial, Scientific & Medical Band – License exempt band
UPCS
1.91 - 1.93
License exempt Personal Communications Services
WCS
2.3
Wireless Communications Service
ISM
2.4 - 2.48
Industrial, Scientific and Medical Band
MMDS
2.5 - 2.7
Multi-channel Multipoint Distribution Service.
Int’l
3.4 - 3.7
4.8 – 5.0
Licensed Bands- Europe, Latin America, Asia
Licensed Bands-Japan
UNII
5.15 - 5.35
5.725 - 5.85
License exempt National Information Infrastructure band
New Spectrum
5.470- 5.725
FCC NPRM 03-110 Part 15
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IEEE 802.22
Wireless Regional Area Networks
 “Wireless Regional Area Network” (“WRAN”) - a network for
operation over large, potentially sparsely populated areas (e.g.
rural areas), taking advantage of the favorable propagation
characteristics in the VHF and low UHF TV bands.
 The unique requirements of operating on a strict non-interference
basis in spectrum assigned to, but unused by, the incumbent
licensed services requires a new approach using purpose-designed
cognitive radio techniques that will permeate both the PHY and
MAC layers.
 The IEEE 802.18 Study Group chartered to develop this PAR does
not believe that any existing IEEE 802 PHY/MAC combination can
meet these requirements without extensive modifications. The
Study Group has therefore concluded that placing the project in a
new Working Group is the most efficient approach.
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”Area Network” characteristics
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Digital VHF – ”VHF Data”
 Telenor has decided to
build a VHF Data radio
system on 50 base
stations, covering the
coastline from Oslo to
Kirkenes
 The system will be in full
commercial operation by
1st quarter 2007
 The project includes a new
customer service platform
as well as other system
improvements:
 IP speed up on 25 kHz




BW channel [21 kbps]
Crypto
Automatic Web and e-mail
compression
Web broadcast
New VHF Data radio using
225 kHz BW [133 kbps]
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Digital VHF – ”VHF Data”




Range: 70 nm ( 130 km) from closest base station
Power: 25 W
Interfaces: Ethernet, RS232
Data rate:
 Narrowband radio: 21 kbps (1 x 25 kHz channel)
 Broadband radio: 133 kbps (9 x 25 kHz channels = 225 kHz)
 Low spectral efficiency !
 Narrowband radio:
 Broadband radio:
0.84 bps/Hz
0.59 bps/Hz (?)
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”VHF/UHF WiMAX” ?
 Robust modulation and access methods
 OFDM (”Orthogonal Frequency Division Multiplexing”)
 High spectral efficiency (
5 bps/Hz,
nominally 10 Mbps/3.5 MHz channel)
 High fading/multipath resistance
[WiMAX is nominally designed to tolerate multipath delay spread (signal reflections)
up to 5/10.0 μs (1.5/3 km)]
 Scalability
 Supports flexible radio frequency (RF) channel bandwidths
 MAC-layer control enables dynamic capacity assignment
 Coverage
 Supports mesh networking and mobile multi-hop relay (MMR) applications
 Optimized for outdoor NLOS performance
 Supports advanced antenna techniques (AAS)
 MAC-layer QoS-support
 Robust security environment
 Supports two quality encryptions standards: DES3 and AES
 All traffic on a WiMAX network must be encrypted using CCMP, which uses
AES for transmission security and data integrity authentication
 End-to-end authentication with PKM-EAP methodology, which relies on the
TLS standard for public key encryption
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On-board LAN
 Network solutions satisfying the vessels needs for local
infrastructure and services (WiFi/WLAN, WiMAX, GSM+, 3G…)
 Advanced middleware enabling a.o. (IP-based):
 Interactive multimedia communications (IP-phone, Internet…)
 Sensor networks implementation
 Seamless and continuous handover and roaming
which is also adapted for integration with the generic scalable
service platform
 An architecture reflecting different security levels (?):
 Intranet for internal communications
 Extranet for cargo control etc.
 Sensor networks for data collection, handling and control
 Ex safety issues/challenges
 Interference issues/challenges
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On-board LAN
Real-time
logistics
Ship
Operations
Service
End-to-End Service Layer & Enablers
Integration
Safety, Security,
Privacy & Trust
Sensor Networks
& Services
Maritime Communication Solutions
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On-board wireless users
 Crew at vessels and offshore installations
 Wireless at Sea (Phone, PDA, PC…)
 Wireless Offshore (Phone, PDA, PC…)
 Safe activities in perilous environments:
 Handsfree at Sea (Ref. PARAT ++)
 Handsfree Offshore (Ref. PARAT++, Helmet-mounted head-up display
etc…)
 Passengers (Phone, PDA, PC…)
 Cargo elements
 Equipment, things….(“An Internet of Things”)
PARAT: ”Personal Audio/Radio Terminal” ”Communications in Rough Environments” , SINTEF
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“Earplug passes the message”
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Thank you !
[email protected]
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