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This paper discusses the behavior of RF MEMS tunable microwave filter. We have modeled the distribution of magnetic field and electric current density in order to reveal the comportment of each device and to evaluate the relation between the frequency response and the microwave performances. From several modelling and simulations, we catch the resonance phenomenon for magnetic and electric fields at different conditions. Hence, in order to develop a reconfigurable MEMS ensuring a function of tunable band-pass filters, we have identified conditions allowing to vary the resonance frequency from Fres = 0.42 GHz to Fres = 1.85 GHz ensuring a large total variation of Tr = 340.5%. The structure is fabricated using SU-8 resin for circulating microchannels and sealing layers. The extracted parameters from measurements results and retro-simulation reveal a diminution of the total tuning range. [ABSTRACT FROM AUTHOR]

Space technology plays a pivotal role in society development. It offers new methods for telemetry, monitoring and control. However, this sector requires training, research and skills development but the lack of instruments, materials and budgets affects the ambiguity to understand satellite technology. The objective of this paper is to describe a demonstration prototype of a smart phone device for space operations study. Therefore, the first task was carried out to give a demonstration for spatial imagery and attitude determination missions through a wireless communication. The smart phone’s Bluetooth was used to achieve this goal inclusive of a new method to enable real time transmission. In addition, an algorithm around a quaternion based Kalman filter was included in order to detect the reliability of the prototype's orientation. The second task was carried out to provide a demonstration for the attitude control mission using the smart phone’s orientation sensor, including a new method for an autonomous guided mode. As a result, the acquisition platform showed real time measurement with good accuracy for orientation detection and image transmission. In addition, the prototype kept the balance during the demonstration based on the attitude control method. [ABSTRACT FROM AUTHOR]

Simulators in power electronics are less developed than in other electronic fields. The main modelling methods are between the numerical simulation of semiconductor device equations that hardly simulate circuits, and equivalent circuit models that show poor accuracy. We propose the application of the bond graph techniques to model modular power semiconductor devices. Furthermore, the IGBT is a new power device which combines a bipolar transistor with a MOSFET transistor. We develop a new IGBT bond graph model. The bond graph techniques give us good primary simulation results. We present in this paper the principle and the results of this modelling method. [ABSTRACT FROM AUTHOR]

Many people in developing countries are required to travel for several hours to see a doctor. The concept of so called telemedicine accompanied with developments in the field of wireless communications may improve the health care. Here presented telemedicine system is for a distance consultation. It is based on a pocket smartphone using its camera to develop a video broadcasting mission for a real-time consultation. However, developing countries in the Middle East and North Africa suffer network coverage in most areas. To overcome this issue, the system includes a software defined radio in order to integrate the small satellite technology in the telemedicine routine. The proposed pico-satellite constellation can provide an interesting solution for near real-time transmission, which will significantly improve the health care in remote areas. [ABSTRACT FROM AUTHOR]

Satellite imagery and data collection have many advantages over other sources of soil observations. The developments in this field lead to the need of reducing cost with improving image construction methods. The concept of so-called satellite constellation accompanied by 3D vision technique may improve the coverage of a specific area. Here presented a satellite constellation conception is for a 3D reconstruction of urban areas, filling the gap of the required temporal resolution to properly monitor this contribution. Thus, a miniaturization method of space vehicles was proposed using CubeSat constellation resides at an altitude of 500 km. The number of satellites required to meet the challenges of earth observation is nine satellites. To accomplish the main goal, meeting the adequate resolution, a development study around a deployable optic camera is presented for a 3D reconstruction. [ABSTRACT FROM AUTHOR]

Costal monitoring is focused on fast response to illegal immigration and illegal ship traffic. Especially, the illegal ship traffic has been present in media since April 2015, as the number of reported deaths of immigrants crossing the Mediterranean significantly increased. Satellite images provide a possibility to at least partially control both types of events. This paper defines the principal criteria to select the best satellite constellation architecture for maritime and coastal monitoring, filling the gaps of imagery techniques in term of real-time control. The primary purpose of a constellation is to obtain global measurement improving the temporal resolution. The small size and low-cost are the main factors, which make CubeSats ideal for use in constellations. We propose a constellation of 9 Cubesats distributed evenly in 3 different planes. This reduces the revisit time enhancing the coverage duration. In addition, it also allows observing fire, damage on building and similar disasters. In this analysis, the performance criteria were reported such as the revisit time, the vision duration and the area coverage. [ABSTRACT FROM AUTHOR]

This paper describes a simple technique for reducing the mobility degradation effect. A current mode squarer circuit and a four quadrant analog multiplier are designed using this technique. The proposed circuits are designed and simulated using the ELDO simulator in 0.18 µm CMOS technology with a power supply of ±0.75 V. The simulation results of analog multiplier for an input range of ±10 µA that demonstrates a −3 dB bandwidth of 300 MHz, a 0.15 mW of maximum power consumption, a low nonlinearity error of 1.1% and a THD of 0.8% in 1 MHz. Monte Carlo simulation of the proposed multiplier is analysed to verify the robustness of the circuit versus the technological process. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the integration of an electroosmotic micropump allowing to generate droplets in two parallel flow focusing junctions. A novel design of the electroosmotic micropump with low voltage is proposed, acting as an active fluidic control to produce droplets of water-in-oil. Numerical studies are performed both on the micropump and the oil flow rate of the continuous phase. The simulations are conducted in terms of size and frequency of droplets issued from the device. Several ranges of applied voltage were applied to the micropump (2, 3.6, 5, and 10 V) for each oil flow rate value varying from 0.75 to 5.5 µl/min. Contrary to the pneumatic, piezoelectric or mechanical micropump, this integrated electroosmotic micropump is a versatile droplet generator allowing it to be used in microfluidic system. [ABSTRACT FROM AUTHOR]

Due to the continuous growth of hardware neuromorphic systems, the need for high-speed, low-power, and energy-efficient computer architectures is increasing. Memristors-based neural networks are a promising solution for low-power neuromorphic systems. Spiking neural networks (SNNs) have been considered the optimal hardware implementation of these systems. Previous studies of SNNs rely on complex circuit to implement in situ bio-plausible STDP learning using memristors, which is computationally challenging. In this paper, we propose an SNN that performs both in situ learning and inference using a new efficient programming technique. Our interest lies in applying the winner-takes-all (WTA) mechanism in the SNN architecture used with recurrently connected neurons, allowing real-time processing of patterns. We provide a programming circuit that enables better weight modulation with less power consumption and less space occupation, using a generalized enhanced memristor model (EGM). The proposed programming circuit is connected to leaky integrate-and-fire (LIF) neurons included in a crossbar architecture to perform recognition task. The simulation results not only prove the correctness of the design, but also offer an efficient implementation in terms of area, energy, accuracy, as well as the ability to classify 40,000 images per second. [ABSTRACT FROM AUTHOR]

The use of LoRa (Long Range) wireless communication as an Internet-of-Things (IoT) protocol has great potential. This technology works in the unlicensed ISM band and covers all the globe with different frequencies, which can improve the wide and rapid spread of information. To obtain global IoT coverage using LoRa, the use of satellite networks is mandatory. The development of nanosatellites, mostly in the CubeSat form factor, for communication applications in general and LoRa communication in particular, is currently increasing. To date, these satellites usually use linear wire deployable antennas for communication. However, deployable mechanical systems present the risk of failure during the mission. In fact, one-unit CubeSat geometry allows a very small space (10 cm * 10 cm * 0.06 cm) for the antenna. Since the size of the antenna is proportional to wavelengths, the antenna size is a large problem for low frequencies, especially in the UHF band. For this reason, planar antennas are an attractive solution for CubeSat communications. This work presents the design of a miniaturized printed monopole meander line antenna working at a frequency of 920 MHz. The novelty of the design is obtained by placing the meander line and the ground plane onto similar sides of the antenna. The meander line allows reduction of the antenna size by a factor of λ/5 for the selected operating frequency. The structure of this proposed antenna has a low profile, and a small size of 50 * 80 * 1.635 mm3 or about 0.153λ 0 * 0.245 λ 0. It has an S11 magnitude of –33.53 dB obtained by simulation and S11 magnitude of −19 dB obtained through experimental measurements. The simulation results also show that the proposed meander line antenna will produce an omnidirectional radiation pattern and a maximum gain of 1.8 dB. [ABSTRACT FROM AUTHOR]

This paper presents a new realization for a CMOS four-quadrant analogue multiplier. The proposed circuit is composed of three second generation current conveyor circuits (CCII), two NMOS transistors operating in the linear region and four passive resistances. It can be operated in current mode and voltage mode without changing the circuit topology. The simulations results of the proposed mixed mode multiplier are verified by TSPICE simulator based on the BSIM3v3 transistor model for TSMC 0.18 μm CMOS process available from MOSIS at 25 °C with ± 0.8 V supply voltage. Through the use of resistive compensation with different passive resistance values, the voltage mode responses present ±0.25 V dynamic range with THD less than 0.114% and wide bandwidth extended from 3.42 GHz to 4.1 GHz. The current mode responses show ±150 μA dynamic range with a maximum THD value about 0.083% and large bandwidth expanded from 2.67 GHz to 3.12 GHz. [ABSTRACT FROM AUTHOR]

This paper presents a low voltage low power operational transconductance amplifier circuit. By using a source degeneration technique, the proposed realization powered at ±0.9 V shows a high DC gain of 63 dB with a unity gain frequency at 3.5 MHz, a wide dynamic range and a total harmonic distortion of −60 dB at 1 MHz for an input of 1 Vpp. According to the connection of negative current terminal to positive voltage terminal of double output OTA circuit, a second generation current conveyor (CCII-) has been realized. This circuit offers a good linearity over the dynamic range, an excellent accuracy and wide current mode of 56 MHz and voltage mode of 16.78 MHz cut-off frequency f-3 dB. Thereafter, new SIMO current-mode biquadratic filter composed by OTA and CCII as active elements and two grounded capacitors is implemented. This filter is characterized by (i) independent adjusting of pole frequency and quality factor, (ii) it can realize all simulations results without changing the circuit topology, (iii) it shows low power consumption about 0.24 mW. All simulations are performed by Cadence (Cadence Design Systems) technology Tower Jazz 0.18 μm TS18SL. [ABSTRACT FROM AUTHOR]

This paper presents static and dynamic studies of a new CMOS realization for the inverting second generation current conveyor circuit (ICCII). The proposed design offers enhanced functionalities compared to ICCII circuits previously presented in the literature. It is characterized by a rail to rail dynamic range with high accuracy, a low parasitic resistor at terminal X (1.6 Ω) and low power consumption (0.31 mW) with wide current mode (3.32 GHz) and voltage mode (3.9 GHz) bandwidths. Furthermore, a new MISO current mode bi-quadratic filter based on using ICCII circuits as active elements is proposed. This filter can realize all standard filter responses without changing the circuit topology. It is characterized by active and passive sensitivities less than unity and an adjustment independently between pole frequency and quality factor. The operating frequency limit of this filter is about 0.8 GHz with 0.674 mW power consumption. The proposed current conveyor circuits and bi-quadratic filter are tested by TSPICE using CMOS 0.18 µm TSMC technology with ±0.8 V supply voltage to verify the theoretical results. [ABSTRACT FROM AUTHOR]

This paper describes the design of a novel cascode-grounded tunable active inductor and its application in an active band-pass filter (BPF) suitable for multi-band radio frequency (RF) front-end circuits. The proposed active inductor circuit uses feedback resistance to improve the equivalent inductance and the quality factor. The novelty of this work lies on the use of a few number of multi-finger transistors, which allows reducing strongly the power consumption and the silicon area. In other words, we demonstrate that the use of variable P-type Metal-Oxide-Semiconductor (PMOS) resistor and controllable current source have a good potential for wide tuning in terms of inductance value, quality factor and frequency operation. The RF BPF is realized using the proposed active inductor with suitable input and output buffer stages. The tuning of the center frequency for multi-band operation is achieved through control voltages. The designed active inductor and RF BPF have been implemented in a standard 0.13m Complementary Metal Oxide Semiconductor (CMOS) technology. The simulation results are compared between schematic and post-layout design for inductance value, quality factor, transmission coefficient S21 and noise. This design yields encouraging results: the inductance value can be tuned from 10.94 to 44.17nH with an optimal quality factor around 2,581. In addition, the center frequency of the BPF can be tuned between 2 and 4.84GHz with an average insertion loss of dB. Throughout this range, the noise figure is between 10.49 and 9.22dB with an input referred 1dB compression point of dBm and IIP3 of 7.36dBm. The filter occupies 25.43m of active area without pads and consumes between 2.38 and 2.84mW from a 1V supplying voltage. [ABSTRACT FROM AUTHOR]

Power converter design requires simulation accuracy. In addition to the requirement of accurate models of power semiconductor devices, this paper highlights the role of considering a very good description of the converter circuit layout for an accurate simulation of its electrical behavior. This paper considers a simple experimental circuit including one switching cell where a MOSFET transistor controls the diode under test. The turn-off transients of the diode are captured, over which the circuit wiring has a major influence. This paper investigates the necessity for accurate modeling of the experimental test circuit wiring and the MOSFET transistor. It shows that a simple wiring inductance as the circuit wiring representation is insufficient. An adequate model and identification of the model parameters are then discussed. Results are validated through experimental and simulation results. [ABSTRACT FROM AUTHOR]

The continued use of high-voltage thyristor devices in industry and their increased use in high-voltage dc transmission systems call for more attention to the properties of these devices. One of the important thyristor parameters is their turn-off time tq, which can be a limiting factor when applying thyristors at elevated switching frequencies. Hence, the accurate measurement of tq and its variation versus the operating conditions remains a crucial task for thyristor converters operating at elevated switching frequencies. In this paper, a proper test circuit for measuring this parameter with a high level of accuracy has been designed and built. Owing to the test circuit specificity, the variation effects of several electrical and physical constraints, such as the forward current IF, the reverse applied voltage VR, the operating temperature To, and the ramp rate of the forward reapplied voltage dVD/dt, on the tq parameter of thyristors are also studied and analyzed based on the physics of semiconductor devices and associated simulations. [ABSTRACT FROM PUBLISHER]

This paper proposes an 8-bit LC tuned digitally-controlled oscillator (DCO) that exploits a new tunable active inductor (TAI) with a high -factor. This TAI achieves a maximum -factor value of 98 over a frequency range of 1770MHz. It tunes from 3.55nH to 15.2nH. The proposed TAI is used in the resonator of a wide tunable low-phase-noise DCO- LC oscillator. The tuning circuitry of the DCO with an additional resistance contributes to better effective capacitance characteristics as compared to the basic topology. Thanks to the capacitive degeneration network formed by a resistance connected in parallel with a capacity, the achieved frequency resolution is between 3kHz and 16kHz without any dithering. The proposed DCO with capacitive degeneration oscillates at a frequency that can be tuned from 1.22 to 3.52GHz with 65% tuning range. It consumes 5.2-mA current from a 1.0-V voltage supply, achieves a phase noise of 105.8dBc/Hz at 1-MHz offset and exhibits a figure of merit (FoM) of 178dBc/Hz. The proposed digitally-controlled oscillator was implemented in TSMC 90-nm CMOS MS/RF technology. [ABSTRACT FROM AUTHOR]

This paper presents a new topology for realizing a single-ended inductor employing a minimum number of passive components. The active inductor achieves a high quality factor of 895 over a frequency range of 1700 MHz. Its self-resonance frequency is 5.5 GHz. The achieved range of sweep for inductance (L) varies from 3.55 to 26 nH. The circuit draws 0.5 mA current from 1.0-V supply and occupies an effective active area of 22 × 27.5 µm2, while the noise voltage is less than. The proposed inductor is designed and simulated in a 90-nm TSMC MS/RF CMOS process. [ABSTRACT FROM AUTHOR]

Accurate simulation is an essential task in designing of integrated power systems to predict their electrical behavior. Thus, a very good description of their wiring circuits is required, and the availability of accurate models of power semiconductor devices and associated design parameters is crucial. This paper focuses on a novel extraction approach of design parameters for a 1-D finite-element-method model of the thyristor. These design parameters are also essential for physics-based analytical models. This paper presents an extraction procedure of the main design parameters of an ultrafast thyristor: the effective area of the device, the ambipolar lifetime, the doping concentration and width of the low-doped base region, and the doping concentration and width of the gate region. The extraction procedure of the thyristor design parameter is based on a comparative computation between simulation and experimental results, taking into account the physics of the component. Measurements are carried out on a sophisticated test circuit, which must be modeled with a sufficient accuracy. This paper details the parameter extraction procedure. Various electrothermal simulation results about the thyristor under test, using the extracted values of design parameters, show good agreement with experiment and confirm the validity of the presented extraction procedure. [ABSTRACT FROM PUBLISHER]

In this work, RF MEMS continuous reversible variable inductor has been fabricated by using microelectronic technology and lamination process. We review, evaluate and compare this variable inductor with other work. The proposed inductor is a dual circular coil and has an inductance of few nH. The fundamental idea is to place a liquid droplet between the metal turns of a coil in order to modify the capacitive /resistive coupling between metal tracks and hence to change the stored magnetic energy. The SU-8 resin was used to realize the microfluidic channels and Au as metallic tracks. To prove the reversibility of the inductor, two cases were studied: filling and emptying of channels. The tuning range of the inductance is approximately 107 % at 1.6 GHz, making these devices very suitable as building blocks in many RF applications. [ABSTRACT FROM AUTHOR]

Abstract: Ground penetrating radar (GPR) is a non-destructive investigation tool used for several applications related to civil infrastructures; including buried objects detection and structural condition evaluation. Although GPR can be effectively used to survey structures, signal analysis can be sometimes challenging. The GPR signals can be easily corrupted by noise because the GPR receiver has usually an ultra-wide bandwidth (UWB). The noise collected by the system can easily mask relatively weak reflections resulting from the inhomogeneities within the surveyed structure; especially when they are at a relatively deep location. This paper presents the use of discrete wavelet transform (DWT) to de-noise the GPR signals. Various mother wavelets were used in this study to de-noise experimental GPR signals collected from flexible pavements. The performance of wavelet de-noising was evaluated by computing the signal-to-noise ratio (SNR) and the normalized root-mean-square error (NRMSE) after de-noising. The study found that wavelet de-noising approach outperforms traditional frequency filters such as the elliptic filter. At the same level of decomposition, the Daubechies order 6 and Symlet order 6 outperform the Haar and Biorthogonal mother wavelets when de-noising GPR signals by soft thresholding. [Copyright &y& Elsevier]

Accurate modelling of PiN diode transient behaviour is necessary to extract design parameters which are not documented in datasheets. To meet this requirement, this paper introduces a novel approach giving the possibility to identify accurate parameters of a given device. The used technique is based only on two stages. First, the design parameters are initialized and optimized. Second, they are refined by minimizing the cost function which depends on the transient switching parameters (IRM, VRM and trr). With a simple and CPU time-saving approach this technique leads to extract design parameters without necessarily knowing the exact technological architecture of the PiN diode. Moreover, in order to validate the proposed approach and the parameter extraction procedure three commercial diodes are tested. A good agreement between experimental and simulation data is obtained. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Commercial power diodes are optimized to feature punch-through behavior. However, a tradeoff between the width and the doping level of the diode epitaxial layer leads to various levels of optimization. For a given breakdown voltage, a shorter epitaxial layer width leads to better transient performances. Device datasheets do not cover this issue and a simple experimental setup is presented to assess the optimization conditions inside the diode epitaxial layer. Three commercial devices are tested and experimental results are confronted to device simulations. A good agreement is found. [ABSTRACT FROM AUTHOR]

Abstract: The paper evaluates the optimal design of the low-doped base region inside power diodes and other bipolar devices. It is demonstrated theoretically that a low-doped base region of P+N−N+ diodes can provide a high breakdown voltage and an optimal on-resistance . A simple, accurate and CPU timesaving approach is presented to extract an optimal value for the base region width, , and its doping concentration, . The paper details an analytical relation between and , and gives a method for quantifying the trade-off between their values for a given breakdown voltage and for obtaining the minimal on-resistance. Analytical results are confronted with experimental results for 4H-SiC- and 6H-SiC-based diodes. [Copyright &y& Elsevier]

Design of integrated power systems requires prototype-less approaches. Accurate simulations are necessary for analysis and verification purposes. Simulation relies on component models and associated parameters. The paper focuses on a step-by-step extraction procedure for the design parameters of a one-dimensional finite-element-method (FEM) model of the PiN diode. The design parameters are also available for diverse physics-based analytical models. The PiN diode remains a complex device to model particularly during switching transients. The paper demonstrates that a simple FEM model may be considered unknowingly of the device exact technology. Heterogeneous simulation is illustrated. The state-of-art of parameter extraction methods is briefly recalled. The proposed procedure is detailed. The diode model and extracted parameters are systematically validated from electro-thermal point-of-view. Validity domains are discussed. [ABSTRACT FROM AUTHOR]

Electro-thermal simulations of a PIN-diode based on the finite-element method, show a non-uniform temperature distribution inside the device during switching transients. Hence, the implicit assumption of a uniform temperature distribution when coupling an analytical electrical model and a thermal model yields inaccurate electro-thermal behaviour of the PIN-diode so far. The idea of including non-uniform temperature distribution into power semiconductor device models is not new, as accurate electro-thermal simulations are required for designing compact power electronic systems (as IC or MCM). Instead of using a one-dimensional finite difference or element method, the bond graphs and the hydrodynamic method are utilized to build an electro-thermal model of the PIN-diode. The results obtained by this original technique are compared with those obtained by a commercial finite-element simulator. The results are similar but the computation effort of the proposed technique is a fraction of that required by finite-element simulators. Moreover, the proposed technique may be applied easily to other power semiconductor devices. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper focuses on the role of the N-N+ junction doping profile model of a PiN diode on its turn-off transient and, particularly, the influence of multiple epitaxies in the N-N+ profile. A conventional doping profile model has been used in a previous work and an identification procedure for the main design parameters has been demonstrated. However the validity range of identified PiN-diode models appeared quite limited for hard current and voltage conditions. Readers have asked for the effect of a more advanced doping profile. The turn-off transient of an STTB506D device is considered from experimental and simulation point-of-view inside a fully characterized switching cell. A limitation of the conventional doping profile model is demonstrated and explained physically in order to introduce the necessity of a more complex doping profile. An advanced doping profile is then considered and a comparative study between experimental and simulated turn-off transient behavior of the device is established. [ABSTRACT FROM AUTHOR]

In this article, a design methodology of an active bandpass filter (BPF) using tunable active inductor (TAI) achieving wide frequency contiguous tuning range (FTR) is presented. The tunable BPF is realized with a differential TAI (DTAI) employing two‐reconfiguration mechanisms one for coarse‐tuning using a controllable current source while the fine‐tuning is performed through a variable feedback resistance. The center frequency tuning is performed through the variation of the DTAI control voltages. A cross‐coupled pair based negative resistance technique is also applied to compensate the resistive losses of equivalent RLC resonator. The filter performances are significantly improved using several optimization techniques such as voltage scaling and multigate finger techniques. The proposed BPF is simulated using 0.13 μm CMOS technology. The filter achieves an insertion loss (IL) of 26.62‐33.45 dB over the tuning range 1.16‐3.27 GHz with a relative bandwidth of 1.3%‐3.4%. The noise figure and input 1‐dB compression point at 1.84 GHz are 14.93 dB and 2.72 dBm, respectively. The designed RF filter consumes an average power of 5 mW at 1 V supply voltage. [ABSTRACT FROM AUTHOR]