An improved integrated SSR antenna system

Work done on integrated feeds for S- and L-band primary radars is described. In the S-band case, a dipole array is used; with the L-band, the SSR signal is injected directly into the primary feed by way of a coaxial probe. The study shows that integrated SSR antennas can provide significant operational improvements when compared with conventional linear arrays. One important disadvantage, however, is that a particular integrated antenna can only be used with one type of primary radar. Ideally, the SSR antenna should be included in the design of the primary antenna rather than being introduced later; this would give better performance and would be potentially cheaper than, for example, the open-array solution.