Building on successful proof-of-principle hardware developed in Phase I, Millimeter Wave Systems, LLC proposes to design, fabricate, and demonstrate the performance of two 65-70GHz latching waveguide ferrite circulator configurations: 1) An innovative Multimode Latching Circulator (MLC™), exploiting two circulating Eigenmodes in a ferrite junction, and 2) latching turnstile ferrite circulators with extended bandwidth using matching networks. The MLC™ takes advantage of the small dimensions, scaling by wavelength, at millimeter wave frequencies to quickly switch the magnetic field. The driver circuitry for both configurations were demonstrated in Phase I and will be enhanced in Phase II. Both topologies have different strengths providing options to the radar designer. The MLC™ innovation allows for a scaling the switch to higher frequencies where the decreasing waveguide dimensions benefit the design trades rather than becoming prohibitive as they do with traditional approaches. With our current fabrication methods, we are confident in reaching frequencies beyond 200GHz.
The proposed work will provide NASA with millimeter wave latching switches for use in remote sensing applications like differential absorption radar for measuring surface level pressure. With low SWAP, the resulting switch would benefit cubesat/smallsat instruments such as RainCube. This work would also benefit high power tube-based radars and radars operating above 200 GHz.
Commercial weather radar companies would benefit from an off-the-shelf solution for high power radar applications. Redundancy switching in hi-reliability communications applications would also benefit from high frequency latching circulators. Recent advances in NMR instrumentation have also created a demand for >200GHz circulators that could be addressed using the developed technology.