AIAA 92 - 0992 Millimeter Wave Seeker Technology

This paper provides a management overview of a new joint Navy/Army millimeter wave (MMW) seeker technology development initiative. The goal of the program is to provide advanced seeker components for endoatmospheric interceptors for theater and strategic missile defense. The technologies are driven by requirements for low weight/volume interceptors, high interceptor and target velocities and a desire for "hit to kill" guidance accuracy (i.e., no interceptor warhead or fuzes). The efforts are focused on Ka (35 GHz) and W (94 GHz) band seeker components. The paper outlines development programs which address high output RF power using solid state transmitters and integrated transmit/receive modules for potential use with active electronically steered arrays. A significant part of the program is directed towards radome development for the severe hypersonic aerothermal environment This includes development and testing of passive and cooled ceramic radomes. The program also addresses means of achieving body fixed or "strap down" seekers (i.e.,-no gimballed, mechanically stabilized antenna platforms). Several approaches are described for implementing both planar and conformal body fixed antennas. The hit to kill guidance issue is addressed in terms of means for achieving high angular tracking accuracy including adaptive boresight error compensation. In keeping with the theme of this "1992 AIAA Aerospace Design Conference," the efforts to be described can be expected to impact future missile seeker design concepts and practices. INTRODUCTION The Naval Air Warfare Center Weapons Division (NAWC-WNS) and the Army Strategic Defense Command have initiated during government FY91 a new effort in MMW seeker technology under sponsorship of the Strategic Defense Initiative Organization's Interceptor Technology Directorate (SDIO/TNC). This initiative was motivated by a need for advanced endoatmospheric interceptors for theater and strategic missile defense. The main focus of this technology program is provided from the requirements of another SDIO program, ENDO LEAF, which is described in another session of this conference. These top level requirements are summarized by: low weight/volume constraint (total seeker weight <6 kilograms) hit to kill guidance accuracies (no warhead or fuze) high interceptor velocities (>2 kilometers/second) high interceptorAarget closing speeds (>4 km/sec) low altitude endoatmospheric intercepts (<25 kilometers) In addition to these "ENDO LEAP type" requirements our technology program also addresses adverse weather performance which, in effect, drives us towards high power output for active RF seekers. Figure 1 provides a conceptual view of the environment in which the future MMW seeker can be expected to operate.