Can a buoy help in setting up a radar properly? (可以利用導航標調教雷達嗎?)
Navigation buoys may be considered as an object to tell if a radar system is properly setup. It has been suggested that it can be considered properly setup and tuned if buoys can be seen on-screen. Is it a reliable mean?
The reflective quality of a radar object depends on numerous factors such as material, size and shape. Amongst the others, they affect the echoed strength and returned direction of radar pulses.
Navigational marks are normally made with steel. In the contrary, those sampan and fishing boats in the picture are constructed with fibre-glass and wood. The reflective quality of these sampan and fishing boats are far inferior to those of steel navigational buoys. The echoes strength of these sampan and fishing boats should be much weaker than those of buoys.
As illustrated, a navigational buoy on the left is not a small object in comparison to sampan and fishing boats. Buoys are taller than most of the small boats in the photo. Apparently, the navigational buoy should have greater chance in reflecting detectable signals.
It may be argued that a can or cone shaped buoy is a poor radar object due to its rounded structure. Except the base that provides buoyancy, a buoy is normally made out of steel frame. Very often, radar reflector is fitted on the top. It appears to be a conspicuous radar object.
In fact, navigational buoys are designed to be picked up with eyes as well as by radar at a reasonable distance. Navigational marks are rather good radar objects in comparison to small boats. Apparently, the detection of navigational buoys will not assure the signals echoed from small objects such as sampan can be detected.