Armament Research

This Phase I proposal describes an effort to develop an Electronic Countermeasure (ECM) hardened proximity fuze sensor applicable to support munition, general purpose bomb, smart-munition and submunition fuzing applications. ECM hardening is achieved by operating the RF sensor at the 60 GHz molecular oxygen (O2) atmospheric adsorption peak. Short-range, radar proximity sensors operating at this frequency would be virtually impervious to stand-off jammers due to the relatively high atmospheric attenuation of the jamming signal, combined with the favorable range advantage enjoyed by the fuze sensor along with the difficulty in producing high levels of RF jamming power at this frequency. Utilizing Monolithic Microwave Integrated Circuit (MMIC) technology, all RF and millimeter-wave circuitry, including the antenna, will be integrated into one or two MMIC chips of minute dimensions. The 60 GHz fuze sensor described in this proposal utilizes frequency-modulated, continuous wave (FMCW) radar techniques in order to remain compatible with existing sensor signal processing circuitry and also to minimize production costs. The RF circuitry consists of a high-power voltage-controlled oscillator (VCO)/buffer amplifier MMIC operating at 20 GHz and producing approximately 0.5 watts of RF power, which drives a second MMIC chip consisting of a Schottky-diode tripler, a passive antenna diplexer, a homodyne receiver mixer, and a single-patch microstrip antenna. This functional partitioning scheme leads to significant advantages: 1) no millimeter-wave packages or interconnections are required, and 2) no exotic MMIC processes are required, since the tripler MMIC is totally passive. During Phase I the sensor will be designed and analyzed, suitable MMIC processes will be selected, preliminary MMIC design will be completed, and a Phase II proposal will be generated. During Phase II, the MMIC chips will be designed and fabricated and a prototype 60 GHz fuze sensor will be designed, fabricated, and performance will be verified utilizing an artificial target generator which will also be developed during the Phase II project.