AIS From Space

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					 AIS From Space
TEXAS III, Washington D.C.,
       August 2009
                    High Performance Space AIS
• COM DEV – a global leader in satellite technology
    –   >$1Billion of supplied space systems

• 5 Years of focused AIS-S Development

• System Design goals:
    –   Full global coverage
    –   Refresh rate < 90 minutes with rapid acquisition
    –   Single pass detection >90%

• Achievements
    –   NTS demonstrates a detection rate far beyond anything achieved in
        known unclassified systems (14 messages/s = 1.2M per day)

•   Constellation service commences Q1 2010
    –   exactEarth subsidiary established to operate this service

           Unmatched Proven Global AIS Detection Capability

 exactEarth (COM DEV) – AIS Activity
• Extensive, high-fidelity
  simulations (2005)
• Harbor testing in
  Vancouver & Halifax
• Aircraft AIS trials at
  29,000 ft. (2007)
• NTS AIS nano-satellite
  launch (2008)
NTS Characteristics
 NANO-Satellite (8 kg), 20 cm cube.
 Limited AIS data storage capacity
(90 seconds of sampled baseband          14 messages/s
data, both AIS channels)                 global average
 Limited AIS data downlink capacity     detection rate
(32 kbps)
 Field of view: 5200 km diameter.
(Altitude: 630 km)
 Attitude control: magnetically
damped. Antenna gain null points
Nadir near the poles.

Demonstration satellite only! Proof of
concept for detection algorithms.
Take 90 seconds of AIS observation,
and then download this over the slow
downlink over a period of about 3-4
Study Conclusions
These studies and experiments made
it clear that high probability ship
detection and the ability to acquire
‘timely’ detections (such as for data
fusion with space based radar)
requires that an AIS satellite must deal
with signal collisions (overlap).

From LEO, there simply aren’t enough
non-overlapped AIS messages in areas
of reasonably high ship density to
allow high detection rates during the
observation fly-over of a LEO satellite
(~ 10 minutes).

For FOVs with > 1000 ships, signal de-
collision is required to achieve usable    N. Atlantic
                                           South Pacific
Atlantic Ocean -                             32 messages/s detection rate in Atlantic
the moderate case and
the Helen Hurdle.
This moderate case can actually serve
as a benchmark. In a 90 second
capture over the Atlantic, 1027
unique MMSIs were detected.                      The ability to detect ships rapidly
In addition, based on                            and often is the key to:
high fidelity system                             Data Fusion applications ,
simulations, the                                 Vessel Traffic Management and
performance of any of                            Ship Tracking situations that
the exactEarth satellites                        require spatial resolution.
is expected to be
approximately 2 to 3
times better than the NTS
demo satellite: 28 to 42
messages/s, per satellite,
global average
                                        NTS - Nano-satellite provides a detection benchmark
Data Results From NTS / Comparisons

APRIL 2008-2009
             90 second snapshot of the globe.

Polar View

                  16,700 Unique MMSIs
   NTS AIS Detection Characteristics
• At TEXAS II, comparison was made between
  NTS and a simple COTS AIS receiver.
• In this presentation a more capable AIS
  receiver is compared to NTS: A sophisticated
  filter-bank that performs sub-channel filtering
  is employed ahead of the COTS AIS receivers.
  – Each sub-channel is shifted to the AIS channel
    center frequency for GMSK demodulation.
  – Doppler compensation for COTS receivers.
             Sophisticated COTS AIS Receiver
                                                  7 sub-channels / AIS channel

                                                                                               AIS message outputs
                                  Subchannel 1            Shift to band center
                                                                                 COTS AIS Rx      1
                    Filter Bank

AIS 1 (25 kHz BW)

                                  Subchannel 7
                                                                                 COTS AIS Rx      7

                                  Subchannel 8                                                    8
                                                                                 COTS AIS Rx
                    Filter Bank

AIS 2 (25 kHz BW)

                                  Subchannel 14                                                   14
                                                                                 COTS AIS Rx
Single exactEarth Satellite in 90 seconds
 AIS Message Extraction Technology
• exactEarth satellites will be more powerful
  than NTS
  – This has been verified by extensive simulations
    using both NTS data as well as hi-fidelity
    simulated data.
  – Differences are due to proprietary technology
• 4 patents pending on COM DEV AIS
Operational Service
 TEXAS III, Washington D.C.,
        August 2009
   exactAIS – Operational AIS-S Service
• NTS high performance DEMVAL
   – Global coverage (includes polar regions)
   – High detection rate

• Operational system being deployed
   – Phase 1: 3-satellite constellation, ground network and
     data center
   – Phase 2: 6-satellite constellation

• Unprecedented Capability
   – Implements proven COM DEV Advanced AIS-S technology
   – Each satellite 100x more powerful than NTS

• Major Capital Investment
 exactAIS – Operational AIS-S Service
• Full service commences Q1 2010
  – Flat subscription fee service
  – Highly secure system
  – Service trials available

• Complete global coverage with rapid refresh
  – Phase 1 (2011) < 6 hour refresh
  – Phase 2 (2013) < 2 hour refresh
  – Much better at higher latitudes

• High Detection rate capability
  – Phase 1 system expected to detect > 11M messages/day
  – Rapid ship detection capability > 1,000 ships/minute, per satellite