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Navico BR24 Radar
Odin SlettenTechnical Sales EngineerNavico Denmark
© Navico Company Confidential2
A Short History of Radar
• In 1917, Nikola Tesla first established the principles for primitive radar units
• In 1935, The British invented and patented the first radar for aircraft defence
• In 1950, Decca introduced the first marine pulse radar utilising a magnetron, which eventually trickled down into recreational boats…
© Navico Company Confidential3
60 Years of Development
© Navico Company Confidential4
Weaknesses of Traditional Radar• User expertise required
– Blurs and distorts objects, making it difficult to interpret surroundings and navigate safely
– Obscures objects closest to the boat, where visibility is most important for collision avoidance
– Difficulty distinguishing targets from clutter - requires experience to safely operate
• Inconvenient installation and operation– Magnetron takes several inconvenient minutes to warm up– Magnetron has a limited life, and is expensive to replace– Large cables and connectors – Power consumption is impractical for small boats and most sailboats– Emissions require mounting away from humans and other electronic
equipment. Most small boats have no room at all
© Navico Company Confidential5
First X-band Radome Radar
© Navico Company Confidential6
Navico’s BroadBand Radar• “Revolutionary improvement in situational awareness” - the best short-
range resolution and target discrimination of any X-band marine radar
– Radar is finally easy enough for a novice – identifies targets clearly with no ‘tune control’, as sea and rain clutter rejection is 5-10 times better than a pulse radar
– Navigation is truly easy, even at an unprecedented 1/32 NM range,
with unparalleled resolution and clarity within two metres of the dome, with no ‘main bang’, ‘zero range adjust’, or close-range sidelobe distortion
© Navico Company Confidential7
Close Range Performance
© Navico Company Confidential8
Comparison and Main bang
4 kW HD pulse radar, 1/8 NM range BroadBand Radar, 1/16 NM range
main bang
© Navico Company Confidential9
Comparison and Main bang
4 kW HD pulse radar, 1/8 NM range Broadband Radar, 1/16 NM range
main bangsuppression
© Navico Company Confidential10
Close Range Performance
© Navico Company Confidential11
Moored boat
4 kW HD pulse radar Broadband Radar
Approximate position of boat
Close Range Performance
Foot bridge
© Navico Company Confidential12
Superb Resolution
4 kW HD Pulse Radar BroadBand Radar
Pile moorings
Moored boat
© Navico Company Confidential13
Seaclutter Performance
4 kW HD pulse radar, 1/2nm
Sea clutter rejection 50%
Two boats, towing into the harbour
BroadBand Radar ¼ NM
No sea clutter rejection applied
What makes the difference?
© Navico Company Confidential15
Traditional Radar
• The radar transmits a powerful, but very short pulse, at a fixed frequency.• The pulse propagates outwards in a direction determined by the angle of the
rotating radar antenna at the time of transmission.• The radar then switches to receive mode to listen for reflections. • If the pulse reflects off an object, it will return to the receiver with a delay
proportional to the distance of the object from the transmitter.• The antenna angle at the time of pulse transmission equals the direction of
the object.
Power
Time
100nsec
Object
Transmitted
ReflectedRadar
Fixed Frequency:9.4GHz
© Navico Company Confidential16
BroadBand Radar
• FMCW = Frequency Modulated Continuous Wave• Transmits a ‘rising tone’ (Tx wave) with linear increasing frequency• The wave propagates out from the transmitter retaining the frequency it
had when it was transmitted• If it reflects off an object, it will return to the receiver, still at the frequency
it had when originally transmitted• Meanwhile the transmitter continues to output an increasing frequency
Frequency
Time
1ms 4ms
9.41GHz9.4GHz
© Navico Company Confidential17
BroadBand Radar
Frequency Difference in Transmitted and Received Signals
The difference in the currently transmitted and currently received frequencies, coupled with the known rate of frequency increase, allows a time of flight to be calculated, from which we can calculate distance.
Frequency
Time
At any instant in time, Tx freq is higher than Rx freq
Tx Rx – retains same frequency it had when it was transmitted
Time delay
Unique Advantages
© Navico Company Confidential19
Solid State – No Magnetron“Start faster, go longer” - 100% solid state RF design – no
magnetron! Provides InstantOn™ power up and low power consumption
– Eliminates 2-3 minutes warm-up time typical of magnetron pulse radars
–Conserves power; operating power drain is ~30% less than the best 2 kW radar (<1/20 in standby mode) – extremely beneficial for sailboats and smaller power boats –No limit on transmit usage lifetime – typically 2-3,000 hours
for a magnetron pulse radar
© Navico Company Confidential20
Two Antenna Arrays
RX
TX
© Navico Company Confidential21
Totally Safe“Incredibly approachable” - Totally safe RF transmitted
emissions and flexible installation setup allows you to mount the radome anywhere
– Extremely low power - less than 1/10th of the transmitted emissions of a mobile phone; install in any position, even on the smallest of boats
© Navico Company Confidential22
Proven Safety
Page 22
Conclusion: Human exposure level to radiation outside the radome is 0.45 W/m2, well below the general public safety emission level of 10 W/m2. Included is the possible case of mechanical failure of the motor or drive belt with the antenna pointing into a fixed direction.
2,8 m (9.3 ft)Standard 4 kW pulse radar
0 m (0 ft)New Navico Broadband radar
1,4 m (4.6 ft)Standard 2 kW pulse radar
Safe DistanceRadar Type
© Navico Company Confidential23
Easy Installation “Incredibly approachable” - Totally safe RF transmit emissions and flexible
installation setup allows you to mount the radome anywhere
– Extremely low power - less than 1/10th of the transmitted emissions of a mobile phone; install in any position, even on the smallest of boats
– Super small custom 13.5 mm RJ45 connector and round 9 mm pre-connected radar cable allows simple bridge tube installations
© Navico Company Confidential24
Radar Interface
Radar Interface Box Fully watertight Small RJ45 connector
© Navico Company Confidential25
Connector
Radar Dome Connection External watertight connector
Same footprint as today’s 2 kW scanner
© Navico Company Confidential26
Mutltiple Displays“Incredibly approachable” - Totally safe RF transmit emissions
and flexible installation setup allows you to mount the radome anywhere
– Extremely low power - less than 1/10th of the transmitted emissions of a mobile phone; install in any position, even on the smallest of boats
– Super small custom 13.5 mm RJ45 connector and round 9 mm pre-connected radar cable allows simple bridge tube installations
–Compatible with a wide range of Navico multifunction displays and heading sensors
© Navico Company Confidential27
Multiple Displays
HDS-5
HDS-5m
HDS-5x
HDS-7
HDS-7m
HDS-8
HDS-8m
HDS-10
HDS-10m
GB40
NX45 12”
NX40 8”
NSE8
NSE12
© Navico Company Confidential28
Super high resolution No blind spot at center (mainbang) Totally safe, 0.1 W TX – install anywhere InstantOn – no warm up time Lower power consumption, no standby power Five times better sea and rain clutter performance Easy to install – very small connector
The Highlights
© Navico Company Confidential29
The Differences Between Pulse and FMCW Radars
Inherent Differences between the technologiesCharacteristic Broadband (FMCW) Pulse
Short range target detection Better Worse
Long range target detection Worse Better
Visibility of close in targets Better Worse
Target resolution in azimuth Same Same
Target resolution in range Better Worse
Sea clutter suppression Better Worse
Power requirements Similar Similar
Requires standby period No Yes
Vulnerability to interference from other radars Difficult to solve Easy to solve
Vulnerability to onboard reflectors Potentially a problem Not a problem
Potential for future development Only just begun Mature technology
Summary from a Technical Briefing by Bill Mullarkey from Navigate-us.comN.B This was purely from theoretical analysis, no practical testing was made
© Navico Company Confidential30
Long Range Performance
Maximum range for any radar under ideal circumstances:
Scanner height
Target Object at sea level Small boat (2 m high) Big launch (6 m high)
2 metres 3.1 miles 6.3 miles 8.5 miles3 metres 3.8 miles 7.0 miles 9.2 miles4 metres 4.4 miles 7.5 miles 9.8 miles
__________________________________________________________________________
So….. there is no possible way a radar on a small/medium boat can see a large launch at more than 10 miles
But… It may be possible to see rain or high land features beyond 10 miles.
© Navico Company Confidential31
Further Enhancement
• Navico’s R&D teams have developed technologies, which bring interference from other radar and onboard reflectors to a minimum or even totally eliminates them.
•This also means we are not depending on already patented technologies, which would have influenced the price of the radar.
© Navico Company Confidential32
Power Requirements
Power consumption transmitting is only 17 W
• 30% less than a 2 kW radar
• 50% less than a 4 kW radar
• Power consumption in standby is only 1.6 W
• The BroadBand radar has no magnetron to heat!
© Navico Company Confidential33
Not Considered in the Report
The very low TX power of the BroadBand radar will often not trigger Racons and SARTs.
Racons are ’active radar reflectors’ on some major buoys used mainly by commercial vessels for long distance radar navigation.
The BroadBand radar cannot be used as the primary radar for rescue vessels, but serves as an outstanding no. 2 radar for close range search.
© Navico Company Confidential34
Additional Benefits
• No 30 m blind spot at centre (mainbang)• Easy to operate. No tuning or adjusting required• Very low sidelobe effects • Totally safe, 0.1 W TX – install anywhere• No magnetron that wears out over time• Easy to install – 9 mm cable and very small connector• Easy to dismantle – external connector at radome
Thank you
Questions?