New radar technology brings sweeping change

by Sandman PR on 6 May 2009 Emitting less radiation than a mobile phone, a new radar system which is about to be released in Australia is destined to revolutionise the country’s $7.8 billion recreational marine industry says the manufacturer.

Developed in Auckland, New Zealand by Navico, the world’s largest marine electronics manufacturer, at a cost of more than AU$10 million, the revolutionary BR24 Broadband Radar is claimed to be the most significant breakthrough in radar technology since 1940.

Due to be officially launched onto the Australian market at the Sanctuary Cove International Boat Show in late May, Navico’s BR24 Broadband Radar is the first radar on the recreational marine market to use Frequency Modulated Continuous Wave (FMCW) technology.

Until now, only the military and big commercial boats could afford FMCW radar.

Most recreational boats use pulse radar.

Pulse radar works by transmitting and receiving pulses of radio waves, alternating between transmission and reception at intervals of microseconds.

Navico’s BR24 Broadband Radar works in a radically different way.

The Broadband Radar transmits continuously, not in pulses. The radar picks up objects within a 24 nautical mile radius by varying the frequency of its continuously transmitted signal, then looking for those variations in the echo.

The BR24 radar offers significant advantages over conventional radar and is a godsend for owners of smaller boats and for mariners who navigate congested coastal waters.

Navico’s Broadband Radar both draws and emits a fraction of the power than that used by conventional radar – an important consideration onboard a boat, which must generate all its own power.

Specifically, it draws a mere 17 watts when operating and a puny 1.6 watts in standby mode. Compare that to the two and four-kilowatt pulse radars that make up the bulk of the market, which use 25-30 watts when operating and 10-15 watts in standby mode.

The BR24 Broadband Radar also produces a miniscule 0.1 watt of transmit power.

That’s about 1/20,000 the amount of energy produced by conventional radars, which typically emit between two and 25 kilowatts, and about 1/10 the amount of energy produced by a mobile phone.

In fact, Navico’s Broadband Radar emits microwaves in such small doses that, unlike conventional scanners, the risk of radiation outside the radome (the case containing the scanner) is nil. Navico says that it means boat owners needn’t worry about mounting the radome at a safe distance from humans and never have to worry about microwave radiation again.

It also means boat owners have more choice about where to install the scanner and a better chance of reducing blind and shadow sectors – the areas behind obstructions such as masts or funnels that block the beams of conventional radar.

Boat owners can place the BR24 radome where it is easier to take down for servicing.

Further, the BR24 has eliminated the dead zone that exists around conventional scanners.

When conventional radar transmits a pulse, it swamps the area immediately around the scanner with its ‘main bang’ (the leading edge of the pulse), which creates a lot of unwanted interference, or ‘noise’.

When the conventional switches to the receive function, it picks up much of that noise, making it difficult for mariners to find targets in their immediate vicinity. This is a big problem when navigating at night or in obscure conditions such as fog or rain, or when undertaking close-in operations such as docking or moving through a narrow, busy channel.

What’s more, even if a conventional radar user tunes the device to minimise the dead zone, the scanner still has trouble discriminating between close-by targets. The user may have trouble telling a fibreglass canoe, say, from a pylon.

Because Navico’s Broadband Radar transmits continuously and not in bangs, it eliminates this dead zone completely. Whereas conventional scanners often have a 30m dead zone around them, Navico’s Broadband Radar picks up objects within 2m of the boat.

The BR24’s range discrimination is also three times better than conventional radar, and users will have a much clearer idea of what the radar is showing them.

Many will be surprised to discover that Navico’s Broadband Radar has no Main Bang Dead Zone tuning control. There’s no need for it.

Another advantage the BR24 offers users is that, compared to conventional radar, it takes no time at all to charge up; it begins transmitting within moments of someone turning it on, as the BR24 has no magnetron.

All conventional pulse radars create microwaves by using a magnetron – a vacuum tube containing a magnet and a cathode, which charges up when voltage is passed through it.

It can take up to three minutes for conventional radar to charge up. Three minutes is a long time in a dangerous situation at sea.

As the BR24 has no magnetron, it is operational with 16 seconds from a cold boot start – and instantaneously from stand-by.

Another advantage the BR24 has over conventional radar is its ease of use.
Conditions at sea change all the time and mariners must frequently adjust their conventional radars to accommodate for variables such as proximity to land, rain, sea-clutter and more.

Each control on conventional radar affects all the other controls, and calibrating conventional radar to function optimally can be time-consuming and confusing, as anyone who has had to mess around with the controls for gain, frequency, pulse length, sea clutter and rain clutter can attest.

Compared to conventional radar, the BR24 requires minimal tuning. Simply turn it on and go.

Navico’s BR24 Broadband Radar heralds a sweeping change in radar technology. Navico Asia Pacific’s chief operation officer, John Scott, puts it this way: 'The BR24 challenges so many of the core assumptions that boat owners hold about radar that it can fairly be called a paradigm shift – recreational marine radar will never be the same again!'

Further information:
Navico Australia – (02) 9936 1000 or visit: www.navico.com

Navico is one of the world’s leading manufacturers of marine electronics and the parent company to five renowned brands: B&G, Eagle, Lowrance, Northstar and Simrad. Visit www.navico.com to find out about our full range of products, including our revolutionary broadband radar and HDS integrated navigation system – new for 2009.