A GPS antenna with anti-jam capabilities utilizes eight resonant loop
radiator elements in a resonant exciter configuration to make available a
primary and up to seven auxiliary antenna patterns usable with
multi-pattern adaptive processing for anti-jam operation. Antennas as
described enable desired radiation characteristics to be provided in a
configuration of small size suitable for replacement of existing GPS
aircraft antennas which lack anti-jam capabilities, in order to enable
reliable GPS reception during airborne operations in the presence of
interference or jamming. With enablement of multi-pattern adaptive
processing, reduced-gain pattern notches or nulls may be employed to
track and reduce the effect of incident signals which would otherwise jam
or interfere with reception of GPS signals.