M. Basha

A study of coupling interactions in finite arbitrarily-shaped grooves in electromagnetic scattering problem.

A study of coupling between finite number of general-shaped grooves in electromagnetic plane-wave scattering problem is presented. The formulation for a single groove [1] is extended to two grooves. The importance of inclusion of coupling interaction between two grooves in scattering analysis is presented and its dependence on the grooves separation distance and the angle of incident of the electromagnetic field is demonstrated quantitatively. For larger angle of incident and smaller separation distance between grooves indicate larger discrepancy between between simulation results with and without inclusion of the coupling effects. Although the results presented here considers two grooves, the formulation can be extended to arbitrary number of grooves.

Label-free DNA sensing using millimeter-wave silicon WGM resonator

A planar dielectric waveguide based structure for bio-sensing purpose is introduced. The proposed device is a silicon-based WGM disc resonator operating within the range of 75-110 GHz (W-band). The sensor is an integrated, miniaturized, low-cost, and easy-to-fabricate bio-sensor structure. The proposed sensor can be used for a number of DNA characterization tasks including Mutation in DNA oligonucleotide. Two types of DNAs, single strand and double strand DNAs, are successfully tested by our integrated sensor. The measurement repeatability and selectivity of the proposed sensor are examined through the different experimental lab-tests.

A low-loss CPW to dielectric waveguide transition for millimeter-wave hybrid integration

A transition from a coplanar waveguide (CPW) to a dielectric waveguide is investigated for the integration of active devices into dielectric waveguide structures. The transition consists of three parts: CPW to a slot line, the slot line to a dielectric waveguide, and a linear tapering part for matching the first and the last parts, respectively. The maximum of insertion loss is -1.7dB, and the return loss is less than -15dB over 7% bandwidth at 60GHz.

Digital Optical 1xN MEMS Switch Utilizing Microassembled Rotating Micromirror

We present a new novel design for a 1timesN digital optical space MEMS switch with a large number of output ports. The switch employs a single rotating micromirror. The rotating micromirror consists of a novel electro-static rotary motor, onto which a 3D mirror structure is assembled using a robotic-based microassembly process. The rotating mirror in the switch can digitally rotate with 480 steps per full revolution in 14.4 msec. A 1.04 dB uniform coupling loss across all output ports is achieved

A rotating micromirror switching element for 1/spl times/N optical MEMS switch

A new novel design for a rotating micromirror fabricated by MUMPs process is presented. The micromirror is elevated at 45/spl deg/ from the micromotors surface. The electrostatic side drive micromotor is designed to have both stepping and continuous rotation. With rotator diameters of 800/spl mu/m and 1000/spl mu/m, a step motion of either 0.75 or 0.5 degree is achieved with total steps of 480 and 720 for full rotation. The rotating micromirror was used to implement a 1/spl times/N optical MEMS switch with large number of output fibers.

Low-cost sub-millimeter-wave/THz integrated system technologies

Three approaches will be presented for low-cost sub-millimeter/THz integrated circuits and systems. Multi-layer planar line monolithic integration, dielectric waveguide hybrid technology, and SOI-based photonic-crystal technique will be described and recent progresses and typical developed integrated devices will be discussed.

Silicon image guide (SIG) coupled resonators antenna for millimeter-wave/THz applications

Recently dielectric antennas have gained a huge interest in millimeter-wave (mmWave) and THz range of frequencies for a wide range of applications such as wireless communication, imaging, and radioastronomy. The most common type of dielectric antenna is the tapered antenna, which is inherently long and radiates in the endfire direction. To realize a down-sized antenna for radiating in a tilted angle, the idea of dielectric resonator in the configuration of dielectric waveguide antennas can be utilized.

A novel free-space MEMS-based variable optical delay line

This paper describes a novel design for a variable optical delay line (ODL) based on modified version of a recently developed MEMS-based 3-D rotating inclined micromirror (3DRIM). The 3DRIM is created by assembling a micromirror onto the top of a rotary comb-drive motor. The comb-drive motor is able to achieve a few degrees of rotation. The new ODL architecture uses two such 3DRIMs located inside a rectangular cavity with mirrored walls. Light from an input fiber is redirected by the 3DRIMs, and caused to reflect within the cavity a number of times, depending on the rotational angle of the 3DRIMs. In this way, the ODL can achieve variable optical delays of up to 3.7 nsec.

A Fourier expansion solution to plane wave scattering from isosceles right triangle groove in perfect conducting plane

While scattering from a rectangular groove, or rectangular slit, in a perfectly conducting plane has been studied extensively, an analytical solution for the scattering problem from an isosceles right triangle (IRT) groove in a perfectly conducting plane has not yet been found. The triangle groove is of practical use in optical and microwave diffraction. An exact analytical solution for the scattering of a plane wave from an IRT groove in a perfectly conducting plane is presented. The spectrum of the scattered fields is expressed as a Fourier expansion related to the field in the groove. Near and far fields can be determined by this presentation of the scattered field in series form.