Low side lobe multi-beam excitation distribution method for deriving the focus away phased-array-fed reflector antenna

摘要

PROBLEM TO BE SOLVED: To automate an excitation distribution search which can reduce a side lobe level of a beam in a broad range with an off-focal point phased array feeding reflector antenna.;SOLUTION: (1) A phase and an amplitude of a radio wave applied to each feeding part for forming a beam in a directional direction are decided by a maximum ratio compositing system to set as an initial value. (2) Concerning a beam pattern by the initial value, a center constraint point and four area end constraint points around a service area are selected. (3) A gain condition at the five constraint points is set to a peak gain or larger of the beam pattern of the initial value, and a minimum gain or smaller in a predetermined service area. (4) The phase and the amplitude are corrected under the gain condition. (5) A side lobe peak to be generated is searched, (6) an abaxial constraint point is set thereto, and the gain condition is set to a desired side lobe gain or smaller. (7) The phase and the amplitude are re-corrected so as to satisfy the gain condition at all the constraint points. (8) (5) and (6) are repeatedly applied. These operations are performed in the beams in different directions.;COPYRIGHT: (C)2011,JPO&INPIT