Optical-MSSW interaction has received wide interest for realization of thin film devices for optical signal processing at microwave signal frequency. In this paper, a device structure to obtain optical-MSSW interaction in a three-dimensional optical waveguide using a multilayered garnet structure is proposed and analyzed. The multilayered structure enables optimization of the waveguide parameters, separately, for optical and MSSW propagation. Interaction in a three-dimensional optical waveguide is promising for integration of the device with other optical integrated circuits. Optical and MSSW propagation characteristics in the multilayered device are investigated and the optical mode conversion characteristics between the Ezpq and the Expq modes supported by the three-dimensional optical waveguide are derived. The dependence of the mode coupling coefficient on the waveguide parameters, such as the film thicknesses, waveguide width, saturation magnetization, and the MSSW power is also analyzed. It is demonstrated through a numerical example that, by proper selection of the waveguide parameters, it is possible to achieve practical device dimensions.

A signal-to-noise enhancer with a bandwidth that is six times as wide as that of the conventional type is presented. A new circuit construction, the combination of two MSSW filters which have the same insertion loss in the broadband and two 90 hybrids, is effective to remarkably extend the bandwidth. The enhancement of the enhancer amounts to 20 dB in the operating frequency range of 1.9 GHz150 MHz in 0 to 60 degrees centigrade. This enhancer has accomplished FM threshold extension because the S/N is improved by 1 to 7 dB below the C/N of 9 dB. It was demonstrated that this new enhancer is effective for noise reduction in practical DBS reception.

An exact analysis for magnetostatic surface wave excitation by a single microstrip is presented. Conventional approaches for such an excitation problem do not explain experimental results in a reasonable manner. The theory proposed here explains radiation resistances obtained by experiments, owing to having considered the edge conditions and an expansion form of excitation current on the microstrip properly.