Patent ID: 7898454
Filing Date: 2011-03-01
Classification: G01S

Abstract:
1. A method of jamming radar apparatus comprising producing a narrow beam of radiation of frequency within the frequency range of the radar apparatus from a source comprising a transmitter in a flying object, and directing the beam towards a scattering surface of the earth distant from the source of the beam, wherein the ratio of the mean jamming power P j of said beam to the peak power P r of said radar apparatus is at least as great as where K is the minimum ratio of jamming signal to echo signal required to jam the radar apparatus, G is the main beam power gain of the antenna of the radar apparatus in the direction of the source of said narrow beam, A is the echoing area of said flying object, L is the main lobe to side lobe power ratio for a side lobe of the antenna of said radar apparatus in the direction of the area of said scattering surface illuminated by the narrow beam, D is the horizontal distance between the radar apparatus and the flying object, H H S is the fraction of the energy of the narrow beam that is scattered upwards.