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This paper introduces a multifunction interactive PV system that has the ability to feed a nonlinear local load in either grid-tied topology (GTT) or off-grid topology (OGT) and transits between the two topologies are seamless. The interactive PV system utilizes a sliding Fourier transform-based phase-locked loop (SFT-PLL) as an adaptive and robust control technique for extracting the fundamental load current. Further, the SFT-PLL is also used to synchronize the inverter output voltage with the grid during the GTT. The proposed synchronization technique has a superior immunity to the weak grid problems. The SFT-PLL based control technique has a very good ability to mitigate the nonlinear load harmonics and to deliver active current to the grid with a unity power factor. Moreover, the proposed control technique is able to keep a balanced grid current when the connected load is unbalanced whether the PV source is available or not. The DC-link voltage is controlled by the controller of the voltage source inverter (VSI) during GTT. During the OGT, the AC load voltage is regulated by the VSI controller while the DC-link voltage is regulated by the boost converter controller to satisfy the power requirements of the connected load. The simulation and experimental results show the effectiveness of the proposed control technique in feeding a balanced current with THD adheres to the IEEE-519 standard at different operating conditions. The performance of the proposed method is compared with recently published adaptive filtering techniques to show its effectiveness especially when the load current has a DC-offset.

IVF success rates vary throughout the world and depend mainly on the nature of the population. Many factors determine the success of IVF. These factors differ from one person to another and from one place to another. The type of fertility problem plays an important and influential role in the success rates of IVF children, and this problem varies according to gender. For example, in women there are cases of tubal obstruction, recurrent miscarriages due to thin endometriosis, cases of uterine abnormalities, and cases of fibroids and the long-term effects of latent TB disease. While some factors of male infertility, there are other factors such as the patient’s age, the duration of infertility, lifestyle and habits, for example smoking causes low sperm count, low motility, and high abnormal sperm. Obesity also causes lower sperm count and slow sperm movement. In this paper, a system will be created based on knowing the effectiveness of IVF procedure for couples and determining its success rate, using logical fuzzy control. A model is developed in which the inputs are a set of test results, the factors affecting the IVF, and the outputs are the success rate of these artificial insemination processes. The reliability and accuracy of the developed model were also discussed and presented.

Recommender Systems have been used widely to provide suggestions to users based on their interests. Although many works have proposed recommender systems in the literature, the majority of these works did not consider the hidden user interests. Even those that considered the user latent interests did not resolve the conflict in interests that could occur. In our previous works, we proposed the use of intelligent agents to extract the interests of user categories such as the interests of a certain gender or the interests of those who work in a certain job. However, there could be some conflicting interests as the user would belong to many categories simultaneously. In this work, we rank the agents according to their ability to extract interests that best represent the users. For this sake, this work takes the user feedback about the most representative agent. Later, it uses classification to predict the most representative agent for new users given their user information. Experimental work proved that our method is efficient in terms of accuracy and training time.

Smart homes provide an easier and more comfortable life by controlling lighting, entertainment, temperature, and creating a safety system that can open doors, communicate with the fire department, and light the road. It uses information technology to monitor the environment, control electrical devices, and communicate with the outside world. Now, the world become highly dependent on the Internet in order to facilitate the life in different fields. Smartphones and computers can be connected at every place with internet to control your homes, companies, factors, and markets. In this paper, A smart home system using GSM and IOT is developed.

The development of a robust and independent wireless sensor node becomes a demand for modern wireless communication. The current study proposes wireless power transfer over a long distance to feed a ZigBee wireless module, which is connected to various environmental sensors. The rectenna design is based on a compact Vivaldi antenna integrated with a multilevel RF -DC rectifier. The antenna provides end-fire radiation with a realized gain of 1–2 dBi at 920 MHz. The RF -DC rectifier is stacked to boost output voltage to higher levels sufficient for supplying the ZigBee module. The demonstration was conducted at a long distance of 9–10 m; the received output power is enough to start-up the communication and keep sustainable data transmission. The data is taken and processed at a remote PC. The measurements were visualized and introduced to illustrate the proposed real application clearly.

Microcomputers mounted on communication modules in IoT devices have low impedance and poor efficiency when the power supply voltage is low. In a weak power supply by energy harvesting, power consumption increases due to deterioration of efficiency at low voltage. Therefore, the DC voltage required to operate the ZigBee module, etc., cannot be obtained, causing a severe problem that startup cannot be performed. To solve the problem, we realized a startup management circuit to cut off the power supply to the ZigBee module until the DC voltage reaches the microcomputer's operating voltage. The proposed system starts at around 2.3 V by using the rectenna operating at 920 MHz band RF signal.

This study demonstrates the application of design principles for tools in Engineering, Procurement, and Construction (EPC) projects for project management purposes. It advocates the use of proper data analytics and visualization that can be implemented to support effective project progress reporting as well as performance monitoring. At first, an Entity Relationship Diagram (ERD) of the collected data was developed, and then the database was retrieved into the Microsoft Power BI for analysis and visualization. The project's relevant details were visualized and analyzed in terms of the major key performance indications that help evaluate the current situation of projects and aids in future decision making for project performance and portfolio management. A real case of a construction company has been selected and examined. Analytical results support finding the story behind the data. On the other hand, the effects point out that the use of the suitable facts analytics method coupled with the right analytics method and appropriate data visualization software would result in optimum use of information for future aspiration of project success and proper project progress reporting and performance evaluation. It will help companies to transfer from traditional data storage style to big data analytics and powerful use of enterprise business data for companies' growth and success in the field of EPC projects and the construction industries as a whole. Furthermore, it can be used for quicker and extra decisive choices aiming to keep projects on music about their security performance, scheduled time, cost, and great level. Using the proposed dashboard is creating a summary of the accessible records that prints a photo of how initiatives and portfolios are performing, permitting decision-makers to take their future strategic steps aiming for the improvement of their initiatives and accordingly success in their cutting-edge and future endeavors to reap the objective of all stakeholders of this organization. In this paper, it was demonstrated that the visualization of the contractor's performance and KPI are bringing assurance on contractor performance in addition to daily operational monitoring. Furthermore, it helps managers in organizing the workload to ensure the project's completion timely and meeting the customer demand as expected.

The Artificial Neural Network (ANN) has become popular in the past few years for its great performance. It is suitable for the nonlinear nature of dynamic systems. The literature contains many articles on the use of ANN in power applications such as voltage stabilization, fault detection, prediction, maximum power point tracking, analytical load component, and power quality. ANN is expected to continue evolving in the next few years, due to the availability of big data for energy applications and the use of deep learning analysis. In this paper, a recent literary survey is conducted on the use of ANN in power applications. Moreover, strengths and week points are shown in order to allow for appropriate selection of the type of ANN which is as important as the selection of ANN parameters.

Sharing power data between electrical power grids is vital issue in energy management. The multi-agent approach has been used in many applications that can support the development of complex systems by making them independent and collaborative. The smart grid is one of the most complex system that expected to have higher level of independence and reliability with adequate protection and adaptation to the response of the user’s request. A multi-agent system is used in this paper to share knowledge and overcome challenges in smart grids. The information shared is used to make a decision that helps in managing power distribution within the grid and with other networks. The presented multi-agent mechanism enhances power system reliability by providing the correct information at the critical time. The results show that the multi-agent system was performed in an efficient and timely manner, which makes it very promising to be excellent candidate for smart grid management.

The availability of different energy sources, such as the conventional and renewable energy sources requires a system that manages these sources and connect them with each other according to specific rules that make the electrical system more disciplined and improve its performance. This requires their integration in smart grids on a common platform to deliver clean and uninterrupted power at low feeding cost. This paper proposes how the distribution system integrated these sources with each other according to many features such as sharing load, operation cost and availability. The system is simulated using MATLAB software 2016. The results show that the smart system is more accurate, reliable, saving feeding cost and simplifies the processing of switching from one station to another automatically controlled by logic control in case fault occurs.

Securing various data types such as text, image, and video is needed in real-time communications. The transmission of data over an insecure channel is a permanent challenge, especially in mass Internet applications. Preserving confidentiality and integrity of data toward malicious attacks, accidental devastation, change during transfer, or while in storage must be improved. Data Encryption Standard (DES) is considered as a symmetric-key algorithm that is most widely used for various security purposes. In this work, a Key-based Enhancement of the DES (KE-DES) technique for securing text is proposed. The KEDES is implemented by the application of two steps: the first is merging the Odd/Even bit transformation of every key bit in the DES algorithm. The second step is replacing the right-side expansion of the original DES by using Key-Distribution (K-D) function. The K-D allocation consists of 8-bits from Permutation Choice-1 (PC-1) key outcome. The next 32-bits outcomes from the right-side of data, there is also 8-bits outcome from Permutation Choice-2 (PC-2) in each round. The key and data created randomly, in this case, provide adequate security and the KEDES model is considered more efficient for text encryption.

Frame synchronization is an important functionality that should be supported in the design of an LTE baseband receiver. Detecting the start of a frame is regularly repeated during transmission and to identify the cells of the network. Typically, the synchronization is performed using correlation-based methods that incur a large number of multiplications and thus increase the power consumption and hardware complexity. Approaches to reduce the rate of multiplications come at the expense of reduced performance of the algorithm. In this paper, we present a multiplication-free synchronization algorithm that is based on K-means clustering and distributed arithmetic and uses the primary synchronization signal (PSS). We also show through simulations that the immense improvement in power consumption and hardware complexity does not entail a degradation in performance compared to current synchronization techniques.

We have implemented a real-time remotely astronomical observation in Egypt. Now that a remote observer would be able to access our 14-inch astronomical telescope (CGE 1400), a dome enclosure, a CCD detector, and various scientific instruments. It is based on a developed integrated system, with a graphical user interface, making use of a TCP/IP protocol. Our platform is more affordable, robust, and applicable for other observatories, even for not computerized systems. Further, neither commercial kits nor software are used. The utilized communication protocol is basically based on row packets to achieve convenient speed in data transfer. We provide a comparison with current commercial systems and previous research in this trend.

Wireless electromagnetic charging becomes an important useful module for the internet of things (IoT) devices. The majority of commercial applications utilize the wireless radiofrequency (RF) charging in 2.45 GHz band. This frequency band ensures the design compactness of either the antenna or the rectification unit. In this study, a compact RF-DC rectifier operating at 2.45 GHz is investigated. The proposed rectifier employs a coplanar strip line (CPS) configuration and a lumped LC component used for the impedance matching. The CPS architecture is selected so it provides a balanced output DC voltage which is appropriate for directly supplying the CMOS circuitry of the IoT devices. The impedance matching is simply constructed using an L-section of reactive elements. To greatly enhances the output DC voltage, the rectifier is built using multistage voltage-doubler configuration. The performance of the rectifier is evaluated, and the measurements were compared with the simulation results. The rectifier efficiency is estimated over the frequency band from 1.8 to 3 GHz, and it indicates a flat response for the RF-DC efficiency. The peak efficiency of the rectifier reaches up to 53% over the band of interest. This rectifier can find several applications in wireless communication and IoT electronic circuits.

This paper presents the design of the micro energy harvesting circuit (MEH) for sensor network systems by using radio wireless waves for wireless telecommunication system. A series L and C resonance circuit is connected in front of the RF-to-DC converting circuit in our proposed circuit in order to enhance the radio frequency (RF) signal. RF-to-DC converting circuit is based on the Dickson voltage multiplier and designed the cascode and cascade connection to obtain the high DC output voltage. Surface mount type devices such as diode, capacitor etc. are placed on the differential strip line. In the simulation, cascade structure has more than 2V DC output from 900MHz to 2.4GHz.

ZigBee wireless communication is used for data transmission between two entities. The power consumption of the unit might fall below a few mW. This energy can be provided by using the RF energy harvesting to wirelessly charge a supercapacitor mounted along with the device architecture. The proposed research work offers a significant solution for the battery replacement and tedious work of the circuit maintenance. A rectenna operating at 920 MHz frequency band is used to charge the supercapacitor with high energy levels that can reach up to a few orders of mW. The harvested energy is rectified by a voltage doubler rectifier configuration. The circuit performance is evaluated, tested, and validated to show the agreement between simulation and measurement data. The system shows that the rectenna can provide at least 3 V for the sustainable operation of the ZigBee module. The connection is programmed to initialize every 5-10 seconds so the supercapacitor can re-charge back to the full capacity. The circuit is experimentally tested for continuous operation in a real environment for more than 24 hours.

This paper presents an attractive simple method for enhancing RF-DC conversion efficiency of the rectifier based on voltage-doubler topology for wireless energy transfer systems. The input matching network and output load of the rectifier are optimized for optimal RF-DC conversion efficiency. Improvement of RF-DC conversion efficiency of 60% was achieved over 67% fractional bandwidth. The lower bandwidth is bounded to 0.8 GHz and the higher bandwidth is twice, 1.6 GHz. The proposed design utilizes a balanced T-impedance matching structure. The rectifier circuit is realized using a differential strip transmission line configuration. The simulated and measured efficiencies of the rectifiers for initial and optimized circuit design are illustrated. The rectifier performance is characterized and the results show that the proposed rectifier can typically achieve 78% at 1.1 GHz which considers the mid-band frequency.

Energy harvesting (EH) becomes one of the important alternative technologies to provide energy for low power electronic devices. The implementation of an independent wireless charging node is mainly depending on the efficient design of the RF-DC rectifier. In this study, a high-efficient and wideband CPW rectifier is proposed. In order to achieve broadband operation, the T-matching circuit is employed. The arms of the matching circuit are composed of reactive LC components to suppress the nonlinearities of the rectification element i.e diode. The rectifier performance is studied and the simulation results are validated with the experimental measurements. The rectifier shows more than 40% efficiency over the band from 0.8 to 2.2 GHz which is sufficient to intercept 400 μW if the incident power is 1 mW. The peak efficiency is 63% at 920 MHz ISM band. Several measurements were taken to demonstrate the agreement between the simulated and measured output results.

This paper proposes optimization techniques for multi-Gbps low-power VLSI implementation of IEEE 802.11n/ac/ax (WiFi) LDPC decoders. The IEEE 802.11n/ac/ax standard features Quasi-Cyclic LDPC (QC-LDPC) codes with modular decoder structure composed of arrays of memory blocks, barrel shifter networks, adders, and check-node units (CNUs). To achieve multi-Gbps throughput performance and high energy-efficiency while maintaining a small decoder footprint, careful implementation of these modules along with effective fixed-point analysis is required. This paper proposes techniques for optimized implementation and proper bit-width selection of these modules. These techniques are then employed to design a fully-pipelined IEEE 802.11n/ac/ax standard compliant LDPC decoder. The design is synthesized in a 40nm standard CMOS process. The synthesized decoder occupies an area of 0.71 mm2, runs at a frequency of 562 MHz, attains a peak throughput of 11.4 Gbps, and achieves an energy-efficiency of 12.5 pJ/bit. The presented decoder outperforms the best-reported decoders in the literature in terms of throughput/area and energy-efficiency, for IEEE 802.11n/ac/ax LDPC codes.

This paper presents an attractive compact design of a small antenna suitable for radio-frequency identification (RFID) and energy harvesting (EH) applications in the UHF band (ultra-high frequency). The proposed antenna is constituted of a nonunifrom radiator fed by co-planar waveguide configuration. The antenna is constructed such that the radiator length is comparable with the wavelength of the electromagnetic wave at the operating frequency. Using this technique reduction in antenna size of equal to 62% with respect to the conventional patch antenna was achieved. The antenna features a simple nonuniform structure and small size of $50\times 60mm^{2}$ or $0.153\ \lambda_{o}\times 0.2 \lambda_{o}$ . It has been fabricated on a low-cost FR4 substrate and the measurements were conducted to validate the practical results with the simulation performances. The antenna performance is slightly shifted to the higher band and it provides an impedance bandwidth of 0.04 MHz (940 - 980 MHz) with reflection coefficient less than 10 dB, which covers all of the ISM band in Japan band (902 - 928 MHz), and Japan RFID band (917 - 923.5 MHz). The design simulation was accomplished using the electromagnetic HFSS software. A good matching results were obtained between the simulated and measured results.

In this paper, a compact dual-band antenna for RF energy harvesting applications is presented. The basic antenna structure is formed using a combination between a dipole and a loop antenna to operate at 900 MHz and 1600 MHz, respectively. To enable the antenna to resonate at a dual- band within a compact substrate, two L-shaped vertical arms as a dipole connected with a trapezoidal slot loop. A meandered transmission line is connected to the coplanar slot line to act as a stub to match the input impedance of the dipole and the loop. On the back of the antenna, a reflector is positioned to enhance the forward to back ratio and provide a unidirectional radiation pattern. The antenna has a compact size $0.149\lambda_{o}\times 0.23\lambda_{o}$ (with respect to the wavelength at the lowest operating frequency), making it comparatively smaller than similar designs. It has a measured fractional bandwidth of 11% at 0.970 GHz at the lower band and 52.9% at the upper band from 1.5 to 2.58 GHz. The antenna performance has a peak gain of 6.5 dB. To prove the antenna normal operation, a prototype is fabricated, tested and the measurements are compared against the simulation results. This antenna is intended for the RF wireless energy harvesting applications.

We propose a computationally-efficient soft-output detector for multiple-input multiple-output channels based on augmented channel puncturing in order to reduce tree processing complexity. The proposed detector, dubbed augmented WL detector (AWLD), employs a punctured channel with a special structure derived by triangulizing the original channel in augmented form, followed by Gaussian elimination. We prove that these punctured channels are optimal in maximizing the lower-bound on the achievable information rate (AIR) based on a newly proposed mismatched detection model. We show that the AWLD decomposes into a minimum mean-square error (MMSE) prefilter and channel-gain compensation stages, followed by a regular unaugmented WL detector (WLD). It attains the same performance as the existing AIR partial marginalization (AIR-PM) detector, but with much simpler processing., 8 pages; International Conference on Communications (ICC), 2020

Wireless energy harvesting has promised to completely change the conventional wired technology for powering the wireless sensor nodes. In the current study, we introduce a high efficient, wideband, and compact RF rectifier for batteryless wireless communication applications. We propose an improved energy harvester which maximizes the efficiency over a wide input frequency range. The proposed design relies on integrating a differential broadband matching circuit with a CMOS rectifier. In order to maximize the operational bandwidth of the cross coupled CMOS rectifier architecture, T-Matching circuit composed of inductive and capacitive elements is suggested. The rectifier along with the matching circuit is fabricated using the standard 180-nm CMOS technology. The measurements of the proposed design were verified against the simulation results. The functionality of the rectifier design, which operates from 1.8 to 4.2 GHz, is studied through simulation in Agilent, ADS and implementation using Cadence, Virtuoso. The simulation and measurement results reveal that the harvester could provide a 2.1 VDC with 5 dBm input power and the efficiency is maintained above 30% over the frequency band of interest. The peak efficiency obtained from the rectifier architecture is 51 % at excitation frequency 2.6 GHz, input power 5 dBm and a terminal load of 3.5 k Ω.

This paper introduces a simple and accurate seamless transfer control strategy for PV Distributed Generator (DG). This seamless transfer guarantees the stable operation of the critical loads fed by the DG during transition from grid connection to the standalone mode or vice versa. This strategy is based on classical PI controller which operates in two modes of operation. The first mode is the standalone mode where the PI controller acts as a voltage regulator. The second mode is the grid connected mode where the PI operates as a current controller. The PV operates in two modes of operation as well. The first mode is the MPPT mode during which a Perturb and Observe (P&O) technique is responsible for maximum power extraction from the PV arrays. This mode is active during grid connection. The second mode is active during standalone operation where a PI controller is responsible for stabilizing the DC-link voltage by manipulating the boost converters duty ratio. The simulation results show the effectiveness of the proposed control strategy.

In this paper, a compact, high gain, simple design, and high efficient single layer slotted dipole antenna is presented. The proposed antenna is fabricated on a low-cost commercial FR4 substrate and is suitable for RF energy harvesting applications. The antenna design relying on a simple modified trapezoidal dipole antenna patterned with a rectangular slot to minimize the inductive loading on the input impedance. A four-arms of a trapezoidal structure are arranged on a half-circle configuration. The performance of the antenna is studied using the simulation and experimental measurements. The antenna offers the main lobe in the z-plane direction with more than 6.5 dBi gain. The input reflection coefficient is measured at 2.45 GHz with a bandwidth extending from 2.4 to 2.5 GHz. The antenna has a small footprint and its dimensions are 32 × 34 mm2.

In this paper, we study frequency-division duplexing (FDD) based cell-free massive multiple-input multiple-output (MIMO) systems wherein distributed multi-antenna access points (APs) serve many single-antenna users simultaneously. Most previous work on cell-free massive MIMO systems consider time-division duplexing mode, although FDD systems dominate current wireless standards. The key challenges in FDD massive MIMO systems are mainly channel-state information (CSI) acquisition and feedback overhead. To address these challenges, we exploit the so-called angle reciprocity of multipath components in the uplink and downlink, so that the required CSI acquisition overhead scales only with the number of served users. We propose a low complexity multipath component estimation technique and present two linear angle-of-arrival (AoA)-based beamforming schemes. We analyze the performance of these schemes by deriving closed-form expressions of the mean-square-error for multipath component estimation, as well as closed form expression for the downlink spectral efficiency. Simulation results demonstrate that the proposed multipath component estimation technique outperforms conventional subspace-based and gradient-descent based techniques. We show also that the proposed beamforming schemes perform close to the ideal beamforming techniques.

Electromagnetic energy can be harvested in the ISM unlicensed band from various ambient source in particular from mobile radio transmitters, Wi-Fi networks, wireless devices. This paper introduces the design and development of a simple rectenna based on a coplanar waveguide (CPW) configuration for operating at the 2.45 GHz ISM band. The rectifier is composed of a one-stage voltage doubler circuit arranged with an inductive input matching network. The antenna is a trapezoidal dipole antenna with a realized gain more than 6 dBi. To build the rectenna, both the rectifier and antenna were simply integrated on single layer FR4 substrate. In order to look insight the circuit performance, the measured and simulated results were demonstrated and the parameters of interest were compared. The rectenna provides a maximum conversion efficiency of 69% at input power 5 dBm, terminal load $2 \mathrm{k}\Omega$ , and driven input frequency of 2.45 GHz. Different experimental constraints were investigated to show the exact circuit response in comparison with the simulation.

We propose a method to estimate the distance to objects based on the complementary nature of monocular image sequences and camera kinematic parameters. The fusion of camera measurements with the kinematics parameters that are measured by an IMU and an odometer is performed using an extended Kalman filter. Results of field experiments with a wheeled robot corroborated the results of the simulation study in terms of accuracy of depth estimation. The performance of the approach in depth estimation is strongly affected by the mutual observer and feature point geometry, measurement accuracy of the observer's motion parameters and distance covered by the observer. It was found that under favorable conditions the error in distance estimation does not exceed 1% of the distance to a feature point. This approach can be used to estimate distance to objects located hundreds of meters away from the camera.

The Wireless Body Sensor Network (WBSN) is used for communication of the sensor nodes operating on or inside the human body in order to monitor the human activities. Wearable sensors can monitor and record real-time information about one’s physiological condition and motion activities. Wearable sensor-based health monitoring systems may comprise different types of flexible sensors that can be integrated into textile fiber, clothes, and elastic bands or directly attached to the human body. In this context, wearable technology has been addressed to make humans (his clothes) able to communicate with, and be part of the interconnected network. The proposed rectenna architecture is designed to harvest energy efficiently in the vicinity of low intercepted power around 0dBm. The rectifier is composed of voltage doubler circuit with LC matching circuit. The antenna is commercially available from flexible conductive film, COCOMI ® , Toyobo Co., Ltd. The overall rectifier dimensions are very compact 19.5 × 9.7mm2. There are a good agreement between the simulation and measurement results. For instance, the peak measured efficiency is 52% at −5dBm RF input power and the corresponding simulated value is 61%. The 63% peak measured efficiency is achieved at 5dBm with a terminal load 5kΩ

Texture classification is the assignment of texture to one or more texture classes. It has been largely used in various fields. This paper proposes a system for Texture Classification using Independent Component Analysis (ICA) using set of classifiers. Independent Component Analysis proved its efficiency in many domains. Our objective is to improve texture classification by adopting the use of ICA with a classifier in this domain. After extracting the main features of the image, classification using set of classifiers is performed. Experimental results have shown that ICA has a promising performance in texture classification. When combined with neural networks, Texture classification accuracy reached the accuracy of 91%. Furthermore, Naive Bayes showed both exceptional training and testing times, and therefore, it proved to be efficient for big datasets.

Currently, technology revolution relies on creating an intelligent environment by establishing interconnections between physical objects or “things” to communicate with each other. Latest Internet of Things (IoT) technology enables prodigious connectivity between autonomous heterogeneous devices/users over multiple access technologies. While, data transfer over such large, dynamic, heterogeneous network usually gets compromised by prying attacks. Therefore, several security approaches are used to guarantee data authentication, identify valid users (host/guest), and detect malevolent and suspicious behavior. In this paper, we employed biologically-inspired Genetic Algorithm (GA) to be part of elastic Software Defined Network (SDN) as controller application to detect suspicious traffic and react either by blockage or by redirection to a honeypot. Simulations showed the efficiency of the presented approach in detecting different types of attacks.

Currently, there is a massive demand for Internet of Things (IoT) devices that can interact and cooperate with each other over multiple wireless networks. Therefore, data transmission between IoT devices emerged as an essential process to ensure connectivity and achieve diverse and intelligent services. Typically, most of IoT-devices share the same frequency band at 2.4 GHz (ISM band), which is free and suitable for many devices. While, the continuous growing of IoT devices makes such frequency band suffers from increasing packet collisions and congestion due to accretion of uplink demand request packets. Therefore, the simple solution relies on using multiple antennas for each band. This solution proposes several challenges toward design implementation and the attached antenna's sizes. In this paper, we propose a quite new technique that can be used to tune frequency band over runtime through a single antenna with the same design. This is achieved through the recent technology of inkjet printing onto flexible substrate to expose such paper-based antenna to different mechanical deformation forces. This will enable manipulation of the antenna operating frequency and bandwidth to dynamically introduce/shift/remove the operating frequency bands over runtime. Simulation results show the ability of antenna to enable direct connectivity between IoT devices depending on twisting the antenna with different angles to establish new several frequency bands.

The extensive increase in the number of IoT devices and the massive data generated and sent to the cloud hinder the cloud abilities to handle it. Further, some IoT devices are latency-sensitive. Such sensitivity makes it harder for far clouds to handle the IoT needs in a timely manner. A new technology named "Fog computing" has emerged as a solution to such problems. Fog computing relies on close by computational devices to handle the conventional cloud load. However, Fog computing introduced additional problems related to the trustworthiness and safety of such devices. Unfortunately, the suggested architectures did not consider such problem. In this paper we present a novel self-configuring fog architecture to support IoT networks with security and trust in mind. We realize the concept of Moving-target defense by mobilizing the applications inside the fog using live migrations. Performance evaluations using a benchmark for mobilized applications showed that the added overhead of live migrations is very small making it deployable in real scenarios. Finally, we presented a mathematical model to estimate the survival probabilities of both static and mobile applications within the fog. Moreover, this work can be extended to other systems such as mobile ad-hoc networks (MANETS) or in vehicular cloud computing (VCC).

Software Defined Networks (SDN) is envisaged as a future model for large-scale, elastic, and adaptive networks. However, such flexibility comes with a major cost. Relying heavily on software across the entire architecture and the centralized nature of the most important component, the controller, gave the attackers asymmetric advantage. for decades, we used to build security tools to secure the network traffic, but network components security was always protected by physical perimeters behind doors. In this paper, we present REPlication prOXY(Repoxy), a smart gateway isolating the north and southbound to enhance controller resilience, availability, and reliability in presence of attacks and also discuss our first version of the implementation. Repoxy presents a novel SDN-controller intrusion detection system to detect any malicious manipulations to the controller software. Further, Repoxy enables elasticity and high-availability for SDN controllers by facilitating southbound-oblivious seamless multi-controller replication, and handover for same network traffic. Additionally, Repoxy helps forensic analysts to easily find attack traces by exploiting Repoxy's information-rich database logging all the switch controller interactions. Results and evaluations showed the enhanced trustworthiness in the SDN network with a reasonable overhead when Repoxy is used.

In this paper, we study the uplink achievable rate by a massive multiple-input multiple-output (MIMO) system in which the base station is equipped with a large number of 1-bit analog-to-digital converters (ADCs). We propose a linear minimum mean-squared error (MMSE)-based detector that accounts for the non-linearity effects of the 1-bit quantization as well as for channel estimation error. An analytical framework that derives the achievable rate of the MMSE-based detector in a massive MIMO configuration under the assumption of 1-bit quantized ADCs and channel estimation error is presented. We compare the achievable rates of a massive MIMO system using a 1-bit ADC and a linear detector against a conventional MIMO system with higher-order modulation and near maximum likelihood (ML) detection. We show that in the low signal-to-noise ratio (SNR) regime with channel estimation error, the quantized massive MIMO system can outperform the conventional large MIMO system; however for high SNR, the conventional MIMO system with a near ML detector can outperform the quantized massive MIMO system.

In this paper, we present a low power Arithmetic Logic Unit (ALU) in 90nm technology using optimized Gate Diffusion Input (GDI) design style. Inspired by the basic ten transistor adder cell compactness, we redesign the architecture of the ALU, by combining the adder and logic functionality in a modified ten transistor cell. The design is compact compared to other designs. For low power applications, we add a transmission gate to isolate the front-end logic section from the backend adder section of the same cell. This restricts power activity only to the logic section when the ALU performs logic operations, leading to more than 2X power savings compared to no-transmission gate implementation. All this comes with less than 9% increase in delay at 1.5V for an 8-bit ALU implementation, and around 50% reduction in the transistor count compared to a traditional GDI ALU implementation with separate logic and arithmetic functionality and enable signals. The design is simulated and verified using a 90nm TSMC design kit.

Low-complexity data detectors targeted for large multiple-input multiple-output (MIMO) systems are considered. By systematically puncturing the channel matrix to have a specific structure, the complexity of standard non-linear detectors can be significantly reduced. The performance of these detectors is characterized and analyzed mathematically, and bounds on the achievable diversity gain and probability of bit error are derived. It is shown that puncturing does not negatively impact the receive diversity gain in hard-output detectors. Moreover, in soft-output detection, significant performance gains are attainable by ordering the layer of interest to be at the root when puncturing the channel. The proposed schemes scale up efficiently both in the number of antennas and constellation size.

This paper presents a novel design of radiofrequency (RF) differential rectifier (DR) for harvesting power as low as 0 dBm. The proposed configuration aims to improve efficiency over extended bandwidth of operation, and further size reduction for low profile RF rectifier circuit. The developed design introduces a balanced output voltage which is suitable for biasing most of the analog integrated circuits, e.g, all circuits based transistor requires $\pm Vdc$ . In addition, the proposed topology provides a measured RF-DC efficiency more than 30% over a relatively wide bandwidth (550M H z) from 0.95GH z to 1.5GHz. Commercial balanced-unbalanced (BALUN) component is used for port transformation. Experimental results show that the system can work with different carrier frequencies and the proposed converter can oprovide a regulated output voltage of $\pm 1V$ over the proposed frequency band at RF input power $P_{in}=5dBm$ , The peak conversion efficiency of the whole system is 57.5% at 1.1GHz.

A dual-frequency rectenna is introduced in this paper. An enhanced-gain antenna is integrated with the rectifying circuit for increasing the rectenna capability for scavenging. A voltage doubler circuit is used for the rectification. Moreover, a four-section matching network is employed for the matching between the antenna and the rectifier. The measured results reveal that the RF-to-DC conversion efficiency is more than 50% over wide range of the input power, from-3.5dBm to 10. 5dBm at f 1 and from -4.5dBm to 11dBm at f 2 , with maximum conversion efficiency of 63% and 69% at input power of 7dBm and 3. 5dBm, respectively with resistive load of$1K\Omega$. Further-more, the measurements illustrate good agreement between the simulated and measured results.