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This paper proposes new solutions for implementing wideband large switch matrices. These solutions are based on crossbar and L-shaped topologies. This paper introduces a high-performance wideband switch cell to build up scalable N x N switch matrices and gives an account of the design, fabrication, and characteristics of the switch cell and a 3 x 3 crossbar switch matrix. The chosen design procedure is seen to be appropriate since it produces valid measured results. In addition, this paper presents an RF microelectromechanical systems L-shaped switch matrix, which indicates less variation of characteristics for certain types of connectivity. It also demonstrates that for a 4 x 4 switch matrix, there is a 50% improvement in insertion loss and phase-shift variation. Index Terms--Microelectromechanical systems (MEMS), RF MEMS, switch, switch matrix and monolithic microwave integrated circuits.

By switching high Q-factor 3-D waveguide bandpass filters with planar radio frequency micro-electromechanical system (RF MEMS)-based elements, a channel aggregation technique is developed in this article. These planar elements play the role of generating an effective phase shift when activated, detuning the resonant cavities of the bandpass filter, and contributing minimal insertion loss when deactivated. The proposed detuning system also has the advantage of not affecting the other operating filter channels connected to manifolds in a switchable waveguide filter bank. A two-channel prototype, based on the Australian satellite Ku-band, with 500-MHz bandwidth, at 14.25-GHz (CH1) and 16.25-GHz (CH2) frequencies, is designed, fabricated, and measured demonstrating the channel aggregation operation. When using only two waveguide bandpass filters with no external switches, four different passband states are implemented, e.g., both channels disable (00), channel 2 enables only (01), channel 1 enables only (10), and both channels enable (11). The system provides excellent channel isolation of better than 35 dB over the disabled channels. For the enabled channels, the filters maintain a measured Q-factor of over 800, and better than 15 dB return loss. The measurements confirm that the detuning elements have a minimal impact on the manifolds and other channel filters, regardless of the operating states. [ABSTRACT FROM AUTHOR]

Through via holes in fused silica are a key infrastructure element of microwave and millimeter-wave circuits and 3D integration. In this work, etching through via holes in ultra-thin fused silica wafers using deep reactive-ion etching (DRIE) and laser ablation was developed and analyzed. The experimental setup and process parameters for both methods are presented and compared. For DRIE, three types of mask materials including KMPR 1035 (Nippon Kayaku, Tokyo, Japan) photoresist, amorphous silicon and chromium-with their corresponding optimized processing recipes-were tested, aiming at etching through a 100 μm fused silica wafer. From the experiments, we concluded that using chromium as the masking material is the best choice when using DRIE. However, we found that the laser ablation method with a laser pulse fluence of 2.89 J/cm2 and a pulse overlap of 91% has advantages over DRIE. The laser ablation method has a simpler process complexity, while offering a fair etching result. In particular, the sidewall profile angle is measured to be 75° to the bottom surface of the wafer, which is ideal for the subsequent metallization process. As a demonstration, a two-inch wafer with 624 via holes was processed using both technologies, and the laser ablation method showed better efficiency compared to DRIE. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents a simple graphical method for introducing phase correction in the electric field for a dielectric loaded substrate integrated waveguide H-plane sectorial horn antenna. An additional pair of rectangular patches with the dielectric loading to the horn antenna provides significant reduction of sidelobe level while maintaining similar gains and beamwidths. Phase plots generated by CAD help explaining the phase correction mechanism and designing. Our studies demonstrated that the reduction of the sidelobe bandwidth is up to 20% of the center frequency. The fabricated antenna operates at 22.7 GHz, and the measured radiation patterns are in good agreement with the simulation results. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:584-588, 2017 [ABSTRACT FROM AUTHOR]

Millimeter-wave reconfigurable bandpass filters with the ability to operate between 60 GHz and the E-band, capable of providing good channel isolation, are presented. A fully integrated filter with all reconfigurable elements embedded for compactness and a switchable filter that uses radio frequency micro-electro-mechanical system (RF MEMS) single-pole double-throw switches are designed. A new method that increases fractional bandwidths is introduced. It uses inductively coupled inverters without requiring their tuning. New circuit models are offered for inverters, reconfigurable resonators, and reconfigurable bandstop stubs. Our compact bandpass filter achieved a footprint of only 4.75 mm × 3.75 mm. Measurements for our filters show good agreement with the results of simulations. [ABSTRACT FROM PUBLISHER]