Abstract: An antenna for a micro air vehicle (MAV) takes the form of a wrap-around antenna (e.g., wrapped around a portion of the MAV) that selectively emits radio signals in different directions depending on a frequency selected by a radio altimeter in the MAV. The radar altimeter may be a pulsed or a frequency modulated continuous wave (FMCW) radar altimeter. The wrap-around antenna includes groups of radiating elements in which at least each group includes an average height that is different from an average height of an adjacent group. Further, the average height of the group determines which group will emit the signals most efficiently so that a desired sector of space may be covered by the signals emitted from the antenna. In one example, the center frequency of the radar altimeter may be controlled in a deterministic manner to cause the radiating elements to successively cover desired sectors of space.

Abstract: An interceptor's point of impact on a targeted missile is quickly revealed in the milliseconds preceeding and following the impact by illuminating the target with radar signals at a high pulse repetition rate and observing the reflected radar echoes on an A-scope display. The position within the returned radar echo of a double echo and related changing phenomenon indicates the point of impact. Failing intercept, the miss distance is computed from the relative slant ranges to the targeted missile, the interceptor, and the double echo. The type warhead killed is revealed by a spectrograph slaved to the radar's antenna. Various techniques assist with the interpretation of the displayed patterns, including subtraction of previously stored patterns and display of the difference, display of characteristic patterns of various known missiles and interceptors stored in "look up" tables, and neural networks.