For radar antennas, a basic distinction must be made between radar antennas and slot antennas. As boat radar on sailing yachts and smaller motorboats a compact and light-weight radar antenna is mainly used. Due to the round encapsulated construction it offers more mounting possibilities on mast or equipment carrier at the stern and it can be well combined with a gimbal suspension. Its power consumption is also lower. Radome antennas usually have a transmission power of 2 kW or 4 kW, which is sufficient for a range up to 48 nautical miles.
Open slot antennas or slot radiators are used on larger yachts and in commercial shipping, where power consumption is less important than higher performance. Due to the narrower aperture angle, slotted antennas provide better target recognition and higher resolution, especially at long range. The transmitting power is usually 4 kW, thus a range of up to 72 nautical miles is possible. Digital radar antennas are now replacing analogue technology. Digital processors allow a better target resolution, the power consumption is lower, the cable cross sections can be reduced. The latest generation of HD Digital radar systems also allows the parallel display of two radar images with different ranges. Depending on the focus on the close range or targets in the far distance, a marine radar transmits on different frequencies. Either on the X-band from 9.3 to 9.5 GHz or in the band from 300 MHz to 3 GHz.
The broadband technology is ideally suited for compatibility with electronic chart systems and sonar displays, for example for a radar overlay. MARPA and AIS functions are also displayed on the radar screen. With MARPA, moving targets such as ships can be tracked in speed, bearing and direction of travel. Dangerous approach points and the time to CPA are displayed. Radar reflectors increase the probability of being detected by radar, especially on GRP yachts and smaller boats. Active radar reflectors amplify occurring radar impulses and send them back, so that even small targets such as sports boats in coastal areas are better detected. High-performance marine radar and radar systems for yachts are offered by equipment specialist Compass under Compass24.