National & International Information

Interference with Radar

Radars "see" solar radio noise emissions whenever their antennas are pointing at the sun. With the low elevation angle scanning regimes in use, this means they generally show streaks of solar noise near sunrise and sunset. It is not necessary for the sun to be abnormally active, as most radars have sufficient sensitivity to see the sun when it is "quiet". In fact solar radio noise is used routinely in maintenance procedures for verifying the directional accuracy of radar antennas and for other radar performance checks.

Another occasional source of spurious signals is interference from other radars and related systems of civilian or military origin. This may take the form of sectors of spots or streaks and in rare cases may be mistaken for areas of rain. Such interference is most commonly seen in the vicinity of airport radars, or in coastal regions during defence force exercises.