Transcript MARITIME NAVIGATION Radar Vladimir LEBEDEV Senior Technical Officer MARITIME SAFETY DIVISION History… • New technologies of Radar become available to Merchant Shipping with the end of hostilities.

MARITIME NAVIGATION
Radar
Vladimir LEBEDEV
Senior Technical Officer
MARITIME SAFETY DIVISION
History…
• New technologies of Radar become
available to Merchant Shipping with the
end of hostilities in 1945
• Radar on Merchant Ships was initially
installed for commercial purposes
– on ferries to maintain better schedules in fog; and
– large fishing vessels
• Radar was treated with great suspicion by
the mariners…
History…
• With improving technology and after
some time the use of Radar for safety
purposes was recognized
• Misinterpretation of Radar
information had not resulted in any
reduction of the number of serious
collisions at sea
History…
• International Conference on Safety of
Life at Sea in 1960 revised the
International Regulations for
Preventing Collisions at Sea by
adding rules to take account of the
use of Radar and recommendations
on the use of Radar information as
an aid to avoiding collisions at sea
History…
• The International Conference on
Safety of Life at Sea in 1974 adopted
provisions to the SOLAS Convention
making Radar a mandatory carriage
requirement for Merchant Ships in a
phased programme starting in 1980,
which finally completed in 2002
SOLAS requirements…
• All Merchant Ships of 300 gross
tonnage and over now shall carry a
Radar and many carry two
• IMO adopted performance standards
for marine Radars, which are used in
connection/integration with other
navigational equipment required to
carry on board ships such as,
SOLAS requirements…
- an automated target tracking aid
- ARPA
- AIS
- ECDIS
- GNSS
- others
NON-SOLAS ships
• Many small craft (millions?) also
carry Radar voluntary as
manufacturers have produced cost
effective designs for their needs
The Shipmaster’s Point of View
• The Key Facts are:
– That Radar remains (and will remain) the
primary system for Collision Avoidance; and
– Radar is a very important tool for Navigation
Why is Radar such a valuable
tool?
• The Master and watch-keepers have
Confidence in information Radar
provides because:
–
–
–
–
It’s operation is Ship based
It’s not reliant on third party sources
It has a proven track record
Radar is useful with SARTs when engaged in
search and rescue
In Short…
• In its display, Radar offers the watchkeepers the basic reality of all targets
relative to the ship
• It therefore aids the watch-keepers
and helps in decision making for
both
– Navigation; and
– Collision Avoidance
COLLISION AVOIDANCE
• Early action is required to avoid a
close quarters situation, therefore
early identification of closing targets
is essential
• Watch-keeping officers need to be
competent in the use of Radar and
are trained in its use and the
application of ARPA
Some IMO requirements…
• Maximum emergency stopping
distance from full speed of the ship
should not be more that 15 ships
lengths
• Emergency turn radius of the ship
should not be more that 2.5 ships
length
Ship parameters…
• Speed – up to 25 knots
• Length
– Largest container ship 335 m
– Capesize bulker 300 m
– Panamax 220-230 m
Ship parameters…
• Emergency stopping distance
3.3 km – 5 km (1.8 nm – 2.7 nm)
• Emergency turning radius
550 m – 840 m (0.3 nm – 0.45 nm)
• Displacement weights
100 000 – 250 000 tonnes
Practical requirements
• To start plotting targets and
determining their course and speed
when the target is between 8 and 10
nautical miles off
NAVIGATION
• Radar gives accurate information on
distance from charted features and
assists in maintaining the ship’s
course
• Radar will normally show a 60 metre
high land mass at a range of 20
miles. This is considered by
seafarers as a minimum requirement
Res. MSC. 192(79)
Target Description
Target description5
Target Feature
Detection Range in NM6
Height above sea level
in metres
X-Band
NM
S-Band
NM
Shorelines
Rising to 60
20
20
Shorelines
Rising to 6
8
8
Shorelines
Rising to 3
6
6
SOLAS ships (>5,000 gross tonnage)
10
11
11
SOLAS ships (>500 gross tonnage)
5.0
8
8
Small vessel with radar reflector meeting IMO Performance
Standards1
4.0
5.0
3.7
Navigation buoy with corner reflector2
3.5
4.9
3.6
Typical Navigation buoy3
3.5
4.6
3.0
Small vessel of length 10 m with no radar reflector4
2.0
3.4
3.0
Discrimination of targets from
a watch-keepers perspective
• To be able to distinguish a tug from
its tow at sea at 12 miles range
• Approaching a rig on a supply
vessel:
• To clearly identify the standby boat from the rig at 6
miles range
• To be able to distinguish the anchor pennant buoys
of a semi submersible rig at 3 miles range
Res. MSC.192(79)
• 5.5.1 Range
– The radar system should be capable of displaying two
point targets on the same bearing, separated by 40 m in
range, as to distinct objects.
• 5.5.2 Bearing
– The radar system should be capable of displaying two
point targets on the same range, separated by 2.5° in
bearing, as to distinct objects.
NAVIGATION
• Radar greatly assists navigation
during poor visibility
• Pilots rely on Radar at close range in
reduced visibility to pass buoys and
beacons.
Res.MSC.192(79)
• 5.4 Minimum Range
5.4.1
With own ship at zero speed, an antenna
height of 15 m above the sea level and in calm
conditions, the navigational buoy in Table 2
should be detected at a minimum horizontal
range of 40 m from the antenna position and up
to a range of 1 NM, without changing the
setting of control functions other than the range
scale selector.
In engineering terms
• Res. ITU-R M.1313
• Power 30-70 kW
• Horizontal Beamwidth 0.75 – 4
degrees
• Pulse width 0.03 – 1.2 microsec
• PRF 4000 – 375 Hz
• Noise figure 3 – 8 dB
Antennae
• Pitch 3 degrees
• Roll 25 degrees
• Yaw 5 degrees
• So vertical beamwidth 20 – 30 degrees
WP 8B Report Nov 03
Radar B
1.0
Baseline = 0.93 +/-0.016
0.9
0.8
Probability of detection
0.7
ENG OB interference 64 QAM
Pulsed interference 1 us 0.1% dc
Pulsed interference 2 us 0.1% dc
Pulsed interference 1 us 1% dc
Pulsed interference 2 us 1% dc
ENG OB interference 16 QAM
CDMA 2000 interference
CDMA wideband interference
0.6
0.5
0.4
0.3
0.2
0.1
-12
-9
-6
-3
0
3
6
9
12
15
18
I/N ratio of interference, dB
21
24
27
30
33
36
39
WP 8B 2001
WP 8B 2001
Thank you!