Triangular Sierpinski Microwave Band-Stop Resonators for K-Band Filtering

Triangular resonators re-shaped with Sierpinski geometry were designed, manufactured, and tested for potential applications in the K-Band. Prototypes of band-stop filters working around 20 GHz and 26 GHz, interesting for RADAR and satellite communications, were studied in a coplanar waveguide (CPW) configuration. Single and coupled structures were analyzed to give evidence for: (i) the tuning of the resonance frequency by increasing the internal complexity of the triangle and (ii) resonance enhancement when coupled structures are considered. The exploited devices were part of the more extended family of metamaterial-inspired structures, and they were studied for their heuristic approach to the prediction of the spectrum using experimental results supported by electromagnetic simulations. As a result, a Sierpinski resonator, not only fed into but also fully embedded into a CPW environment, had a frequency response that was not easily determined by classical theoretical approaches

MEMS-Switched Triangular and U-Shaped Band-Stop Resonators for K-Band Operation

Triangular resonators re-shaped into Sierpinski geometry and U-shaped resonators were designed, linking them with single-pole-double-through (SPDT) RF MEMS switches to provide frequency tuning for potential applications in the K-Band. Prototypes of band-stop narrowband filters working around 20 GHz and 26 GHz, interesting for RADAR and satellite communications, were studied in a coplanar waveguide (CPW) configuration, and the tuning was obtained by switching between two paths of the devices loaded with different resonators. As a result, dual-band operation or fine-tuning could be obtained depending on the choice of the resonator, acting as a building block. The studied filters belong to the more general group of devices inspired by a metamaterial design

RF-MEMS Components and Networks for High-Performance Reconfigurable Telecommunication and Wireless Systems

MEMS (MicroElectroMechanical-Systems) technology applied to the field of Radio Frequency systems (i.e. RF-MEMS) has emerged in the last 10-15 years as a valuable and viable solution to manufacture low-cost and very high-performance passive components, like variable capacitors, inductors and micro-relays, as well as complex networks, like tunable filters, reconfigurable impedance matching networks and phase shifters, and so on. The availability of such components and their integration within RF systems (e.g. radio transceivers, radars, satellites, etc.) enables boosting the characteristics and performance of telecommunication systems, addressing for instance a significant increase of their reconfigurability. The benefits resulting from the employment of RF-MEMS technology are paramount, being some of them the reduction of hardware redundancy and power consumption, along with the operability of the same RF system according to multiple standards. After framing more in detail the whole context of RF-MEMS technology, this paper will provide a brief introduction on a typical RF-MEMS technology platform. Subsequently, some relevant examples of lumped RF-MEMS passive elements and complex reconfigurable networks will be reported along with their measured RF performance and characteristics

U-shaped MEMS tunable microwave resonators

Compact, U-shaped microwave resonators have been designed and implemented with RF MEMS switches to obtain frequency tunable narrow-band devices. The U-shape has been used to develop a resonator optimizing its size. In addition, RF MEMS ohmic switches have been introduced to implement the frequency tunability in a small range and to provide a high signal rejection ratio in the ON-OFF states. Device configurations working at frequencies between 20 GHz ca. and 26 GHz ca. have been studied

Metamaterials based RF microsystems for telecommunication applications

In this paper, metamaterial and microsystem concepts have been used to study resonating structures useful for narrowband microwave signal processing. U-shaped resonators and triangular Sierpinski structures have been designed, manufactured, and tested for possible applications in the K-Band, around 20 GHz and 26 GHz, for satellite communications. Results on the metamaterial nature of both configurations and on their electrical performance are discussed. The studied structures include the possible implementation by RF MEMS of the U-resonators. The outlined novelty is in obtaining a tunable narrow-band filter using an all-passive environment with switches embedded in the resonator. The advantages and drawbacks of this solution and the proposed optimization are discussed in detail. Triangular resonators with the Sierpinski geometry are also considered for the same frequencies. In this case, the possibility to tune the frequency of operation is demanded to increase the complexity of the internal geometry of the triangle by means of empty sub-triangles in the metal path. Examples of the expected performances for coupled triangular structures are also presented

Non Linear Compact Modeling of RF-MEMS Switches by Means of Model Order Reduction

In this work, a new method is presented for the extraction of low order electromechanical models for dynamic nonlinear simulation of radio frequency (RF) microelectromechanical (MEMS) switches, using model order reduction (MOR). The method is based on a separate modeling of the electrical and the mechanical part of the problem, which are coupled at circuit level. The derived reduced order model includes effects of initial stress in the device materials and enables a substantial speed-up of large signal dynamical analysis. The accuracy of the model has been demonstrated by comparing the simulated and measured dynamic response of a fabricated device