Abstract: A method for compensating for the failure of an element in a phased array antenna assembly is provided. After failure of an element of the assembly, a composite pattern is generated from signals received by respective elements in the antenna assembly. This generated pattern is then compared to a standard composite pattern which was generated prior to the failure. Thus the necessity for remedial action can be assessed. If necessary, initial values for parameters associated with each element are assumed and an optimization is performed on the parameters. Consequently, a composite pattern can be generated which approximates the standard composite pattern. Once optimization has been achieved, the optimized parameters are applied to base settings for the assembly and operation of the phased array antenna assembly can be continued.

Abstract: A method for compensating for the failure of an element in a phased array antenna assembly is provided. After failure of an element of the assembly, a composite pattern is generated from signals received by respective elements in the antenna assembly. This generated pattern is then compared to a standard composite pattern which was generated prior to the failure. Thus the necessity for remedial action can be assessed. If necessary, initial values for parameters associated with each element are assumed and an optimisation is performed on the parameters. Consequently, a composite pattern can be generated which approximates the standard composite pattern. Once optimisation has been achieved, the optimised parameters are applied to base settings for the assembly and operation of the phased array antenna assembly can be continued.

Abstract: In a radar antenna system comprising antenna elements arranged in an active array, the elements are located in predetermined groups such that an individual group can be selected electronically from within the whole array aperture, the said selection being effected by variable attenuator means. This produces a phase difference between direct and multipath reflections so that the radar information from a direct reflection can be distinguished from multipath information.