This paper describes the design, assembly and field testing of a LHCP (Left Hand Circularly Polarized) high gain helical antenna. The antenna is to be utilized for the reception of reflected Global Positioning System (GPS) signals, which are correlated with the direct signals to form an image of the area of interest. Thus the antenna forms a constituent element of a remote imaging system. Owing to the low power of the reflected GPS signals the major design parameter was obviously high gain, while maintaining the polarization integrity of reflected GPS signals. *
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