Design of Two Element Triple Band MIMO DRA with Enhanced Isolation for LTE Applications

A new two element hybrid MIMO DRA is presented for LTE operation. The presented MIMO having two elements excited with CPW feeding. This is operating under hybrid TM mode. MIMO is intended on partial ground with thickness of 0.035 mm, substrate (FR-4) with dielectric constant (εr) of 4.6, thickness 1.6 mm and loss tangent 0.019. The DRA is placed on the two elements individually. The dimensions of the presented MIMO are 90 X 107.8 X 13 mm3. The antenna gives a multiband to covers 0.8 GHz, 1.5 GHz, and 1.7 GHz for |S11| ≤ -10 dB. The proposed MIMO can cover LTE Band 5 and Band 6 at 0.84 GHz with operating band width of 83.2 MHz (0.8106 – 0.8938 GHz), LTE Band 21 at 1.5 GHz with operating band width of 45.4 MHz (1.4825 – 1.5279 GHz) and LTE Band 9 at 1.7 GHz with operating band with is 72.6 MHz (1.7382 – 1.8108 GHz). The simulated isolation of -74.96 dB, -75.53 dB and -81.41 dB are obtained with respect to the mentioned frequencies, respectively. MIMO provides very good radiation efficiency >140 % at band-1, > 81% at band-2 and >82% at band-3. The proposed antenna is discovered to attain good isolation, better impedance matching, low Envelope Correlation Coefficient (ECC) and adequate gain. Hence, This MIMO suitable for LTE applications. The HFSS software is used for the simulation.

Design Optimization of Centrifugal Microfluidic “Lab-on-a-Disc” Systems towards Fluidic Larger-Scale Integration

Enhancing the degree of functional multiplexing while assuring operational reliability and manufacturability at competitive costs are crucial ingredients for enabling comprehensive sample-to-answer automation, e.g., for use in common, decentralized “Point-of-Care” or “Point-of-Use” scenarios. This paper demonstrates a model-based “digital twin” approach, which efficiently supports the algorithmic design optimization of exemplary centrifugo-pneumatic (CP) dissolvable-film (DF) siphon valves toward larger-scale integration (LSI) of well-established “Lab-on-a-Disc” (LoaD) systems. Obviously, the spatial footprint of the valves and their upstream laboratory unit operations (LUOs) have to fit, at a given radial position prescribed by its occurrence in the assay protocol, into the locally accessible disc space. At the same time, the retention rate of a rotationally actuated CP-DF siphon valve and, most challengingly, its band width related to unavoidable tolerances of experimental input parameters need to slot into a defined interval of the practically allowed frequency envelope. To accomplish particular design goals, a set of parametrized metrics is defined, which are to be met within their practical boundaries while (numerically) minimizing the band width in the frequency domain. While each LSI scenario needs to be addressed individually on the basis of the digital twin, a suite of qualitative design rules and instructive showcases structures are presented.

Effects of characteristic element length on fracture energy dissipation in continuum damage mechanics models

Progressive damage finite element (FE) analysis methods based on continuum damage mechanics (CDM) use mesh regularization algorithms to ensure that fracture energy dissipation predictions are independent of problem discretization. Mesh regularization algorithms require some geometric input related to the discretization. When using crack band theory for mesh regularization, a characteristic element length is used to approximate the width of the region affected by the continuum crack, i.e., the crack band width. Inaccuracy in representing the crack band width significantly affects predictions in terms of fracture energy dissipation. For square elements misaligned by 45°, using a typical line length across an element rather than the crack band width overestimates dissipated fracture energy by 41%. Not accounting for element aspect ratio underestimates dissipated fracture energy by 29% and 50% for ratios of two and four, respectively. Herein, methods for calculating characteristic element lengths in fiber-reinforced materials are presented that account for meshes being misaligned with respect to material directions, element aspect ratio, and element skew. The limits of applicability of different crack band width approximations are explored through numerical crack growth studies and center notch tension FE analyses for different discretizations. Results are compared in terms of fracture energy dissipation to linear elastic fracture mechanics. Analyses with the proposed characteristic element lengths predict consistent fracture energy dissipation with various meshes. The proposed methods and the included studies on potential error in fracture energy dissipation provide analysts the basis to better understand error in CDM model predictions associated with simplified FE model preprocessing.

Design Optimization of Centrifugal Microfluidic "Lab-on-a-Disc" Systems towards Fluidic Larger-Scale Integration

Enhancing the degree of functional multiplexing while assuring operational reliability and manufacturability at competitive costs are crucial ingredients for enabling comprehensive sample-to-answer automation, e.g., for use in common, decentralized “Point-of-Care” or “Point-of-Use” scenarios. This paper demonstrates a model-based ‘digital twin’ approach which efficiently supports the algorithmic design optimization of exemplary centrifugo-pneumatic (CP) dissolvable-film (DF) siphon valves towards larger-scale integration (LSI) of well-established “Lab-on-a-Disc” (LoaD) systems. Obviously, the spatial footprint of the valves and their upstream laboratory unit operations (LUOs) have to fit, at a given radial position prescribed by its occurrence in the assay protocol, into the locally accessible disc space. At the same time, the retention rate of a rotationally actuated CP-DF siphon valve and, most challenging, its band width related to unavoidable tolerances of experimental input parameters, need to slot into a defined interval of the practically allowed frequency envelope. To accomplish particular design goals, a set of parametrized metrics is defined, which are to be met within their practical boundaries while (numerically) minimizing the band width in the frequency domain. While each LSI scenario needs to be addressed individually on the basis of the digital twin, a suite of qualitative design rules and instructive showcases structures are presented.

Zero-Width Quasi-Sliding Mode Band in the Presence of Non-Matched Uncertainties

Sliding mode control strategies are well known for ensuring robustness of the system with respect to disturbance and model uncertainties. For continuous-time plants, they achieve this property by confining the system state to a particular hyperplane in the state space. Contrary to this, discrete-time sliding mode control (DSMC) strategies only drive the system representative point to a certain vicinity of that hyperplane. In established literature on DSMC, the width of this vicinity has always been strictly greater than zero in the presence of uncertainties. Thus, ideal sliding motion was considered impossible for discrete-time systems. In this paper, a new approach to DSMC design is presented with the aim of driving the system representative point exactly onto the sliding hyperplane even in the presence of uncertainties. As a result, the quasi-sliding mode band width is effectively reduced to zero and ideal discrete-time sliding motion is ensured. This is achieved with the proper selection of the sliding hyperplane, using the unique properties of relative degree two sliding variables. It is further demonstrated that, even in cases where selection of a relative degree two sliding variable is impossible, one can use the proposed technique to significantly reduce the quasi-sliding mode band width.

FABRY - PEROT TUNABLE FILTERS

Tunable light filters are widely used for selecting different bands of wavelengths in the UV, visible and IR spectrum. Their advantages are simplicity, accuracy and high mono-chromaticity. By varying magnetic field it is possible to adjust the filter and select desired wavelength if necessary. In the paper a research on tunable light filters based on Fabry-Perot interferometer (FPI) is presented. These light filters can be tuned in the wavelength range from 400 nm to 1000 nm, in IR band of 8 - 12 μm, with spectral pass band width between 0.5 μm and 1 μm, out of band rejection than 10꞉1 with a resolution of 0.5 - 1.5μV.

Implementation of Efficient Reconfigurable FIR Filter With Control Logic for 5G Applications

Filters are used to achieve frequency selectivity on the spectrum of input signal. Due to the stability of FIR filters, they are used in most of the applications. In the conventional FIR filters the frequency band is fixed and can‟t be changed once it is designed. Hence there is a necessity of an FIR filter with auto adjustment of band width. The design of FIR filter requires more number of filter coefficients to get the desired bandwidth specification. This results in a large slice for FPGA implementation. Here it is proposed a state machine to select different FIR filters with the designated set of coefficients. Each FIR filter is having different set of coefficients and based on the frequency of the clock signal the FIR filter is selected. Therefore frequency selectivity can be achieved. The Proposed method is to implement Reconfigurable FIR Filter with control logic for auto adjustment of fre-quency selections to achieve better band width requirements. The filter order is initially selected as 4 and presented the simulation results. The order of the filter(n) increased to 24 for verifying the bandwidth selection. The proposed architecture is compared with the existing architecture with 16bits and 11taps. Simulation results presented are verified using Xilinx ISE design suite 14.7. Total number of 4 input LUTs utilized are 630 for n=24. Power consumed by the overall design is 195mW.