Multi-Band Rotary Joint for Antenna Feeds/Waveguides Navy SBIR FY2005.1 Sol No.: Navy SBIR FY2005.1 Topic No.: N05-084 Topic Title: Multi-Band Rotary Joint for Antenna Feeds/Waveguides Proposal No.: N051-084-0299 Firm: Millitech LLC 29 Industrial Drive East Northampton, Massachusetts 01060 Contact: Tom Newman Phone: (413) 582-9620 Web Site: www.millitech.com Abstract: Millitech has a high level of expertise in the design of millimeter-wave hardware and has long been in the business of exacting the maximum amount of performance out of a minimum of volume, mass, and available power, in our component and system designs for the space community. We have a potential solution for the rotary joints for the particular case of the subHDR system upgrade, which can be designed during phase I, and built and tested during phase II. The design of the elevation and cross-elevation rotary joints will use a unique combination of low-loss coaxial line, terminated with a non-contacting waveguide transition on each end. The coaxial line will replace a circular waveguide TM01 line, which trades off power handling for bandwidth. By optimizing the size of the coax, however, the power handling is still 41.7 kW, a factor of 16X the power currently planned for the system, with comparable loss to the current design. The train rotary joint will use a similar technique for the upper frequency bands and a novel non-contacting scheme for the X band circuit path, rather than the current slip ring, enhancing the reliability considerably as well as reducing the cost of the part. Benefits: Upgrading the rotary joints is an important step in upgrading existing satellite communication systems for further communication bands to be added. That the multi-band rotary joints are non-contacting will greatly enhance the reliability and lower the cost of such systems. The applications for these rotary joints cover both military and commercial applications. It will be now possible to cover all of the military (or all of the commercial) Satcom bands with a single rotary joint. The applications go well beyond Satcom alone, and cover any broadband application of microwave and millimeter-wave signals. Return