What is Broadband radar?
The Navico Broadband Radar uses FMCW (Frequency Modulated Continuous Wave) radar technology.
How is FMCW radar different?
Firstly it is solid state – i.e. the transmitter is a semiconductor device, not based on magnetron technology. Secondly, it transmits a 1ms long signal of increasing frequency, rather than a short duration pulse. Thirdly, it measures the distance to a target not by timing the returned echoes, but by measuring the difference between the current transmitted frequency and echoed frequency. Hence FMCW – Frequency Modulated Continuous Wave. The building up of the image over 360 degrees and the processing of the radar data is the same as for a magnetron radar.
How does FMCW radar work?
FMCW = Frequency Modulated Continuous Wave
The scanner transmits a ‘rising tone’ (Tx wave) with linearly increasing frequency. The wave propagates out from the transmitter retaining the frequency it had when it was transmitted. If it refl ects 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.
The difference between both the currently transmitted and received frequencies, coupled with the known rate of frequency increase, allows a time of fl ight to be calculated, from which dis-tance is calculated.
- Additional benefits of FMCW radar are:
- Low energy emissions. 1/5th of a mobile phone
- Safe operation in anchorages and marinas
- Instant power up. No warm up required
- Short range performance
- Broadband radar can see within a few meters of the boat, compared to pulse radars, which can not see closer than 30 meters
- Higher resolution clearly separates individual vessels and objects
- Up to five times better sea and rain clutter performance
- Low power
- Suitable for small boats and yachts
- Easier installation with lighter cabling and smaller connectors
- Great for yachts on ocean passage
- Instant power-up
- Conventional radars take 2-3 minutes to warm up the magnetron: Safety – 2 minutes is a long time if you are concerned about
- Convenience – switch it on and use it.
- Easy to use
- No constant adjusting required to obtain optimum performance
- No re-tuning between ranges. Means fast range change at all ranges