THALES Radar System
How Marine Radars Work
A marine radar antenna is continuously rotating on top of a ship or radar station , sending and receiving signals . Hence , the radar is sweeping the signals all around the source . It emits out radio waves as a high-speed signal which travels in the direction the radar is facing . If there are no objects in the direction of the radio waves , the radar screen shows blank .
If there is an object , which reflects the wave back to the radar , the computer set up of the radar logs the position and determines the distance between the ship or radar station and the distant object together with its location . Hence , the radar basically reads two things – the position and the direction of the object . The computer calculates the time taken for the signal to reflect back to the radar . Once the computer knows the time , it measures the distance by using the speed and time formula . Radar receivers are usually in the same location as the transmitter . The reflected radar signals captured by the receiving antenna are usually very weak . They can be strengthened by electronic amplifiers . Nowadays , more sophisticated methods of signal processing are also used in order to recover radar signals .
In a marine setting , radars are rarely used alone . They are always integrated with other navigation displays such as a GPS navigation chart projected on a single screen , as it becomes quite distracting to look at several different screens . This provides a combined view of surroundings and makes it easier to manoeuvre the ship . On commercial ships , radars are integrated into a full system of marine instruments including sonar , chartplotters , two-way marine radios , satellite navigation receivers ( Global Navigation Satellite System ) and emergency locators . A chartplotter is a device used in marine navigation that integrates GPS data with an electronic navigational chart ( ENC ). The chartplotter displays the ENC with the speed , position and heading of the ship and may display additional information from radar ,
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