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A slotted microstrip patch antenna for fifth‐generation (5G) mobile applications is presented in this paper. The proposed antenna addresses the intrinsic narrow bandwidth of patch antennas by introducing rectangular slots in the form of a disjointed H‐slot to broaden the bandwidth. The patch design and the slots introduce two extra resonances to broaden the bandwidth of the antenna. An impedance bandwidth of 26.6% from 24.95 to 32.6 GHz was achieved. A measured peak gain of 9.44 dBi was also achieved with a minimum half‐power beamwidth of 36° over the entire bandwidth. The proposed slotted patch antenna is implemented on a 44.6 mm × 26.3 mm × 0.8 mm RT5880 Printed Circuit Board. [ABSTRACT FROM AUTHOR]

With the development of multimedia technology, more and more colleges and universities apply network multimedia technology in art teaching to achieve the improvement of the art teaching effect. After analyzing the application scenarios of D2D, D2D technology is combined with social networks to create a teaching classroom where teachers and students can collaborate. A communication link is established in the network classroom to facilitate the sharing of art education content. Combine the network terminal caching system to improve the cache hit rate by caching multiple identical contents. Integrate network multimedia technology into art education and examine its contribution to education. The results show that the caching effect of multimedia technology is mainly reflected in four aspects: completeness, clarity, smoothness, and speed. When the number of caches reaches 12, the caching speed of the teaching content fluctuates in the range of 0.75-0.8. When the number of caches is less than 12, the caching fluency of the content is in the range of 0.85-0.9. This study provides a new direction to promote the reform of art education, which is conducive to improving the teaching effectiveness of art education and cultivating art talents.

In order to effectively and automatically select communication links and reduce the global risk of communication, this paper proposes an automatic selection method of power 5G communication links based on risk balance. First of all, taking the lowest global risk and the highest service channel availability as the objective functions, and taking the channel bandwidth, delay and packet loss rate as the constraints, the automatic selection model of power 5G communication link is established. The business risk degree is evaluated by taking the business risk degree and the network business risk balance degree as indicators. According to the degree of risk, the communication services are sorted from the lowest to the highest. The automatic selection model of communication links is used to give priority to the selection of links for the services with lower risk. The automatic selection model of communication links is gotten through quantum genetic algorithm, to obtain the lowest global risk and the highest service channel availability value, and complete the automatic selection of communication links. Experiments show that this method can effectively obtain the risk degree of each communication service, automatically select the communication link, reduce the global risk degree, improve the availability and bandwidth of the service channel, reduce the channel delay and packet loss rate, and achieve better risk balancing effect.

Copyright of Aero Weaponry is the property of Aero Weaponry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Online adaptive protection scheme provides an appropriate protection to microgrids for various fault conditions irrespective of bidirectional power flow and changing network topology in a grid-connected or islanded mode of operation. The success of this scheme can, however, be undermined as a result of the operational uncertainties caused by the failure in various components in protection system: namely, communication links and circuit breakers. This paper proposes a framework for assessing the impact of such uncertainties on the reliability of centralized adaptive microgrid protection schemes. It first derives appropriate Markov chain models to describe the dynamic uncertainties associated with lines, communication links, and circuit breakers. The Markov models are then used in a Monte Carlo algorithm to evaluate the reliability indices for an adaptive protection scheme. The proposed framework is tested on a sample microgrid in Simulink-Matlab and Java Agent DEvelopment platform, assuming that the respective communication middleware is carried out by multi-agent and communication simulator. It has been shown that the selection of communication technology in an adaptive protection scheme requires special attention to its failure rate and data transmission bit error as well as data transfer speed. In fact, communication technologies with high failure rate and bit error show poor reliability indices that can cause unwanted delays in fault clearance, particularly when GOOSE time sequence latency is considered in the analysis. Besides, an increase in the fault duration can increase the electromagnetic and thermal stresses inflicted on circuit breakers, further undermining the reliability of the protection system. [ABSTRACT FROM AUTHOR]

In case of an error in the power system, it is the duty of the protection relays to isolate the faulty part from the rest of the system as soon as possible. Overcurrent and distance relays are usually used to protect the transmission and super distribution systems. The optimum coordination of these relays is very important. In this article, communication links are used to improve the optimal coordination of overcurrent and distance relays. In the proposed plan, the overcurrent relays on both sides of the line are equipped with a communication link for immediate action in the event of an error. Using this communication link, the complete coverage of the line is also provided by distance relays. The number and place of installation of the communication link greatly affect the operation time of overcurrent relays and the distance and coordination between them. The coordination problem is formulated by considering the location and number of communication links, and to solve it, the combined optimization algorithm of genetics and linear programming will be used. With the help of the genetic algorithm, the location and setting of the second zone of the distance relay, and by using the linear programming algorithm, the setting of the overcurrent relays is determined. The proposed method has been tested on the IEEE 14-bus (the simulation in MATLAB software) network and its results examined, and it will be seen how much the existence of a communication link can improve the performance time of the protection system. [ABSTRACT FROM AUTHOR]

The abnormality of communication link of mobile Internet of Things will threaten the security of communication of mobile Internet of Things, and the existing abnormality detection method is limited due to low accuracy, long time consumption and high energy consumption. To this end, the anomaly detection method of communication link of mobile Internet of Things based on EM algorithm is proposed in this study. Firstly, the anomaly range of the Internet of Things is located according to the communication node information of the data changes. Then the abnormal link of the target is judged and the anomaly feature of the communication link of the Internet of Things based on twin neural network is extracted. Finally, EM algorithm is improved with semi-supervised machine learning method to detect abnormal communication links of mobile Internet of Things. The experimental results show that the proposed method has the advantages of high precision, short time consumption and low energy consumption in the anomaly detection of communication links in the Internet of Things. [ABSTRACT FROM AUTHOR]

To solve the problem of low message delivery rate and high network resource consumption when forwarding messages in opportunistic networks, an opportunistic routing algorithm based on trust relationships for wireless mesh networks is proposed. Firstly, the wireless mesh network is analyzed and the opportunistic routing model is constructed; By analyzing the security mechanism and security threat of communication entities, then measuring the trust degree of links and nodes, establishing the trust relationship between nodes, and defining and quantifying a new security measurement method based on the trust model; Finally, according to the security measurement method defined by the model, select the node with high trust value to participate in the message forwarding process. At the same time, give priority to the node with greater trust with the destination node as the relay node, and allocate the message copy according to the trust degree to make the message pass along the direction of increasing trust, to complete the design of opportunistic routing algorithm in wireless mesh networks. Experimental results show that the routing algorithm can effectively improve the message delivery rate, up to about 95%, and reduce the consumption of network resources.

An ultra-miniaturized implantable antenna for scalp and deep tissue implants operating in the Industrial, Scientific, and Medical (ISM) frequency band is proposed in this communication. The proposed antenna has a compact size of only 4.422 mm3 ( $3.45\times 3.4\times0.377$ mm3). A meandered patch backed by a full ground plane was used to implement the proposed ultra-miniaturized antenna. The full ground plane does not allow backward energy flow, thus ensuring patient safety. The performance of the proposed antenna was evaluated in three different simulation environments: homogeneous skin phantom (HSP), skin implant multilayer phantom (SIMP), and muscle implant multilayer phantom (MIMP) models with and without a dummy implantable wireless device (IMD). These models were considered to evaluate the performance of the proposed antenna in more realistic complex human body environments. The proposed antenna demonstrated excellent impedance matching performance at the ISM band with a measured −10 dB impedance bandwidth of 260 MHz (2,249–2,511 MHz). The effects of coaxial cable on antenna performance were also studied. The proposed antenna exhibited a maximum measured peak gain of −26.54 dBi. Furthermore, the 1-g and 10-g specific absorption rate (SAR) values were calculated and satisfied the safety guidelines. A reliable communication link up to distances of 15, 4, and 1.3 m for bit rates of 7 kbps, 100 kbps, and 1 Mbps, respectively, can be established between the implantable device and external base station. Finally, a sensitivity analysis of the proposed antenna was conducted showing that the proposed implantable antenna can efficiently work under varying tissue conditions.

Line-of-sight clarity and assurance are essential because they are considered the golden rule in wireless network planning, allowing the direct propagation path to connect the transmitter and receiver and retain the strength of the signal to be received. Despite the increasing literature on the line of sight with different scenarios, no comprehensive study focuses on the multiplicity of parameters and basic concepts that must be taken into account when studying such a topic as it affects the results and their accuracy. Therefore, this research aims to find limited values that ensure that the signal reaches the future efficiently and enhances the accuracy of these values' results. We have designed MATLAB simulation and programming programs by Visual Basic .NET for a semi-realistic communication system. It includes all the basic parameters of this system, taking into account the environment's diversity and the characteristics of the obstacle between the transmitting station and the receiving station. Then we verified the correctness of the system's work. Moreover, we begin by analyzing and studying multiple and branching cases to achieve the goal. We get several values from the results, which are finite values, which are a useful reference for engineers and designers of wireless networks. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The traditional acquisition process of environmental parameters is easily affected by environmental noise, which leads to prolonged data transmission time and low data integrity. To solve this problem, with the STM32 processor adopted, the alarm circuit was used to avoid the problem of too large or too small data collection, and then the anti-interference design of the system was realized through the configuration of decoupling capacitor and the design of ground wire, so as to reduce the data transmission delay. Based on this, Kalman filtering algorithm could be used to restore the performance of real data, remove the environmental noise of communication link, and realize complete parameter acquisition. The experimental results show that the data transmission delay of the system in this paper can be kept below 15 s and the effective integrity of the parameter data is always not less than 0.96 regardless of single hop or multi hop transmission.

Based on the ISO/IEC 18000-6C standard protocol, this paper conducted research on the design and implementation of UHF RFID tag′s physical layer baseband circuit. According to the design requirements and indicators of the baseband specified in the standard protocol, SystemVerilog was used to model the tag sending and receiving basebands, and the theoretical derivation and design implementation of the key modules in the baseband were given. SystemVerilog, as a hardware description and verification language developed on the basis of Verilog, can greatly improve the efficiency of SoC design. Finally, Modelsim SE-64 10.4 was used to simulate the digital baseband circuit design of the tag. The results showed that the digital baseband met the requirements of ISO/IEC 18000-6C protocol. This design provides a design reference for single-chip UHF RFID tag.

The National Remote Sensing Centre (NRSC) has established its ground station named Antarctica Ground Station for Earth Observation Satellites (AGEOS) at Bharati station located at Larsemann hills area of Antarctica for the tracking and data acquisition from polar orbiting satellites. A communication link through a geostationary satellite in C-band is being used for transferring data to the mainland. There is a need to enhance the data rate in the near future considering the huge volume of data being acquired at AGEOS. A satellite link operating at Ka-band is proposed for accommodating the bandwidth requirements. It is necessary to estimate the worst case atmospheric attenuation at Ka-band over Larsemann hills area for calculating the link margins required. The India Meteorological Department (IMD) has setup a wide range of meteorological instruments at Bharati station and the local data collected for the years 2020, 2021 and 2022 are used in this study. The link is assumed to operate at a frequency of 20 GHz with linear polarization. An exceedance probability of 0.1% is used to arrive at the annual statistics of the attenuation. Recommendations by the International Telecommunication Union (ITU) are followed and the estimation is carried out using MATLAB. An estimated total atmospheric attenuation of 2.28 dB is obtained. The results are used further for carrying out link budgeting for a Ka-band satellite communication link between Bharati station and India. [ABSTRACT FROM AUTHOR]

In case of an error in the power system, it is the duty of the protection relays to isolate the faulty part from the rest of the system as soon as possible. Overcurrent and distance relays are usually used to protect the transmission and super distribution systems. The optimum coordination of these relays is very important. In this article, communication links are used to improve the optimal coordination of overcurrent and distance relays. In the proposed plan, the overcurrent relays on both sides of the line are equipped with a communication link for immediate action in the event of an error. Using this communication link, the complete coverage of the line is also provided by distance relays. The number and place of installation of the communication link greatly affect the operation time of overcurrent relays and the distance and coordination between them. The coordination problem is formulated by considering the location and number of communication links, and to solve it, the combined optimization algorithm of genetics and linear programming will be used. With the help of the genetic algorithm, the location and setting of the second zone of the distance relay, and by using the linear programming algorithm, the setting of the overcurrent relays is determined. The proposed method has been tested on the IEEE 14-bus (the simulation in MATLAB software) network and its results examined, and it will be seen how much the existence of a communication link can improve the performance time of the protection system.

This paper reveals a millimeter-wave point-to-point radio link of MPSK (QPSK, 8-PSK, and 16-PSK) modulation without the need of an analog to digital converter (ADC). The proposed point-to-point radio link uses the clock and data recovery (CDR) applied in the optical-electrical converter (OEC) to recover the MPSK intermediate frequency (IF) signals frequency offset as well as the radio over fiber (RoF) concept to extend the transmit distance of the central unit and the remote radio unit. The proposed point-to-point synchronous radio link removes the high-speed ADC requirement for the digital-intermediate-frequency-over-fiber (DIFoF) link, which can significantly reduce the complexity and the expense of the remote radio unit compared with the standard RoF link. Simultaneously, we have designed a simple symbol synchronization algorithm to realize the real-time point-to-point radio link on a Field Programmable Gate Array (FPGA). The proposed millimeter-wave radio link has successfully demonstrated 6 Gbps QPSK transmission and can tolerate a frequency offset up to 100 MHz. [ABSTRACT FROM AUTHOR]

Based on modern sensors, communication networks and computing technologies, wide-area protection system (WAPS) can acquire electrical quantities to precisely locate faults in smart grids. In WAPS, the communication network is responsible for rapidly and reliably transmitting data between a regional master station and its slave stations. The real-time data transmission is heavily dependent on the communication link (CL) placement. In addition to the rational partitioning of WAPS, the CL placement should be chosen so as to ensure the good performance of WAPS. The aim of this study is to extend the traditional partitioning of WAPS to the simultaneous optimization problem of partitioning and optical CL placement. The simultaneous optimization problem is formalized so as to minimize the construction cost of WAPS. Besides the optical CL placement and partitioning, to ensure the reliable and real-time transmission of data, the link bandwidth and cost of each optical CL is also captured in the optimization problem. Finally, numerical simulations are carried out on the IEEE 39-bus, 57-bus and 118-bus standard testing cases. The simulation results illustrate that the optical CL scheme can be non-negligible and that it will significantly influence the partitioning of WAPS. [ABSTRACT FROM AUTHOR]

The traditional acquisition process of environmental parameters is easily affected by environmental noise, which leads to prolonged data transmission time and low data integrity. To solve this problem, witht he STM32 processor adopted, the alarm circuit was used to avoid the problem of too large or too small data collection, and then the anti-interference design of the system was realized through the configuration of decoupling capacitor and the design of ground wire, so as to reduce the data transmission delay. Based on this, Kalman filtering algorithm could be used to restore the performance of real data, remove the environmental noise of communication link, and realize complete parameter acquisition. The experimental results show that the data transmission delay of the system in this paper can be kept below 15s and the effective integrity of the parameter data is always not less than 0.96 regardless of single hopor multi hop transmission. [ABSTRACT FROM AUTHOR]

A coded pilot assisted high data rate millimeter-wave receiver topology is presented in this article. A low data rate and low power pseudorandom noise (pn) coded pilot signal is superimposed at the transmitter, and the receiver can use such pilot for carrier recovery (CR) and/or channel estimation regardless of modulation scheme or communication data rate. The proposed baseband receiver has an analog–digital hybrid structure where a low-cost digital signal processor is used. This structure requires only a low-cost analog-to-digital converter (ADC) with a sampling rate of 40 MSPS. A proof-of-concept communication link at $E$ -band is demonstrated with 18 Gbps 64-quadrature amplitude modulation (QAM) and 24 Gbps 16-QAM. [ABSTRACT FROM AUTHOR]

This study presents a single-end protection algorithm for current source converter (CSC) high-voltage direct current (HVDC) transmission lines to solve shortcomings such as inadequate sensitivity, low speed and the need for communication link of conventional protection schemes. The proposed algorithm uses the average of DC line current at the rectifier terminal, sampled at 4 kHz within a 5 ms window, for simultaneous fault detection and faulted pole selection. For fault discrimination, the algorithm uses the average of second-order difference of the sampled current data. The algorithm is verified by extensive simulation studies using a CSC-HVDC test system modelled in PSCAD, as well as field data. The simulation results show fast and reliable protection of CSC-HVDC lines under different fault conditions including high-fault resistances. Moreover, the novel protection algorithm is stable against resistive–inductive faults, power flow changes, change of data window length, lightning interference and size of smoothing reactor. The algorithm does not require a communication link as used by numerous previous methods. It has a low computational burden, low sampling frequency and can be easily implemented in practical CSC-HVDC systems without extra arrangements as the required signals are readily available in the existing measuring hardware platforms. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the last couple of decades, the industry saw an increase in the number of wireless sensor networks (WSNs) in replacement of the old cabled technology due to lower deployment and maintenance costs. To keep this momentum, those industrial WSN (IWSN) must assure robustness, scalability, low power, and low maintenance, and the network protocol stack is an important piece of this puzzle. One great dilemma faced by IWSN protocols is how to sustain reliable radio links while avoiding draining too much energy from the battery. In this context, Wireless HART (WH) and ISA SP100.11a, for example require the hardware of the nodes to provide multiple power levels for transmission. Unfortunately, those protocols do not provide a standard procedure to choose between those levels. A simple but inefficient solution often employed simply chooses the highest level available. Seeking a better solution, this proposal presents a transmission power control (TPC) methodology that allows energy saving while sustaining the quality of the communication link employing a simple proportional–integral (PI) controller plus anti‐windup. The proposed approach does not rely on special TPC‐related packets, which is advantageous in comparison with other approaches from the literature by allowing this work to be fully compliant with existing IWSN protocols. [ABSTRACT FROM AUTHOR]

This study proposes a reconfigurable wireless charging topology, which achieves load‐independent constant current (CC) and constant voltage (CV) output without any communication link between transmitting and receiving coils. The proposed topology is suitable for CC–CV modes of battery charging. Inductor (L), capacitor (C) and inductor (L) connected as T type (LCL) compensation with an auxiliary capacitor on the transmitting side and series (S) compensation on the receiving side (LCL‐S) is used to achieve load‐independent CC and CV output. Reconfiguration has been achieved using single AC switch on transmitting side. Control has been implemented with the information on transmitting side. Load‐independent CC and CV output operations have been analysed analytically. The merits of the proposed topology are fixed‐frequency operation, simplified control scheme for load‐independent CC–CV operation without any communication link. Feasibility of the proposed topology is verified by the experimental prototype with a CC output of 12 A and CV output of 56 V. [ABSTRACT FROM AUTHOR]

The penetration of distributed generators (DGs) of large capacities in micro‐grid introduces a considerable difference of current seen by the relay, during faults in its primary and backup region. This leads to several issues with the protection system such as relay miscoordination, delay in relay operation or failure in the relay operation (blinding). This study discusses a methodology to solve such issues by identifying the current status of micro‐grid configuration. The proposed method performs well by maintaining the coordination time interval (CTI) between the relays, irrespective of the source strength (weak or strong), the mode of operation of the micro‐grid (islanded or grid connected) or the micro‐grid configuration (radial or looped). The method proposes three curves with different settings in a single relay. A suitable algorithm has been developed to calculate the relay settings for all the three curves of each relay, well in advance and this program is made to run in the central master controller (MC). Thereafter, MC sends the settings of all relays through a reliable communication channel. The proposed relaying scheme provides desirable CTI margin as compared to conventional over current relay. The simulation results of the novel protection scheme are validated through hardware emulation. [ABSTRACT FROM AUTHOR]

This study proposes holistic network performability as a reliability index of multiple autonomous underwater vehicle (AUV) (multi-AUV) cooperative systems and deduces the reliability of communication links. Temperature and salinity vary in different areas of the sea. The influence mechanism of temperature and salinity on holistic network performability is discussed. An example is provided to show the influences of temperature and salinity on holistic network performability. Corresponding trends of holistic network performability with the influences of temperature and salinity can be obtained. The trends show that the holistic network performability of multi-AUV cooperative systems exhibit ladder-like increases with temperature and salinity. In each ladder, the value of holistic network performability changes rapidly at high salinity or low temperature. The study on the change of the reliability of multi-AUV cooperative systems under different temperatures and salinities provides a theoretical basis for the reliability research of multi-AUV cooperative systems and provides reference for future practical application of multi-AUV cooperative systems and other network systems. [ABSTRACT FROM AUTHOR]

Modern radar applications, such as automotive, integration of radar and communications, have become an important requirement. Systems able to provide joint radar and communications would exploit the same hardware while providing enhanced capabilities to the carrying platform, such as road situation awareness and content sharing. In this article, a novel framework for automotive radars based on the fractional Fourier transform (FrFT) is introduced. The aim of the proposed approach is to preserve radar performance while integrating a communication link. Simulation results demonstrate the potential of the proposed framework for automotive applications. [ABSTRACT FROM AUTHOR]

Modern radar applications, such as automotive, integration of radar and communications, have become an important requirement. Systems able to provide joint radar and communications would exploit the same hardware while providing enhanced capabilities to the carrying platform, such as road situation awareness and content sharing. In this article, a novel framework for automotive radars based on the fractional Fourier transform (FrFT) is introduced. The aim of the proposed approach is to preserve radar performance while integrating a communication link. Simulation results demonstrate the potential of the proposed framework for automotive applications.

This paper discusses the controllability problem of complex networks. It is shown that almost any weighted complex network with noise on the strength of communication links is controllable in the sense of Kalman controllability. The concept of almost controllability is elaborated by both theoretical discussions and experimental verifications. [ABSTRACT FROM AUTHOR]

Due to the relatively high costs of phasor measurement units (PMUs), the optimal PMU placement problem of minimizing the number of PMUs for full system observability has long been a popular research topic. However, PMUs alone will not make a system observable. An appropriate communication network that transmits all PMU data to the phasor data concentrator plays a key role. This paper proposes the optimal PMU-communication link placement (OPLP) problem that investigates the placement of PMU and communication links (CLs) for full observability in a power system. In addition to the location of PMUs and CLs, to ensure the reliable and timely transmission of PMU data, the communication capacity needed on every CL is captured by the OPLP problem. We carry out numerical studies on the IEEE 30-bus, 57-bus, 118-bus, and 300-bus systems for the proposed models. The results reveal that, when compared to the traditional optimal PMU placement model, OPLP can reduce the total installation cost significantly. [ABSTRACT FROM AUTHOR]

This paper presents a 64-element 28-GHz phased-array transceiver for 5G communications based on $2\times 2$ transmit/ receive (TRX) beamformer chips. Sixteen of the $2\times 2$ TRX chips are assembled on a 12-layer printed circuit board (PCB) together with a Wilkinson combiner/divider network and 28–32-GHz stacked-patch antennas. The 64-element array results in 1.1 dB and 8.9° rms amplitude and phase error, respectively, with no calibration due to the symmetric design of the $2\times 2$ beamformer chips and the PCB Wilkinson network. The effect of phase and amplitude mismatch between the 64 elements is analyzed and shown to have little impact on the 64-element array performance due to the averaging effects of phased arrays. Detailed pattern, effective isotropic radiated power (EIRP), and link measurements performed without any array calibration are presented and show the robustness of the symmetrical design technique. The phased array can scan to ±50° in azimuth ($H$ -plane) and ±25° in elevation ($E$ -plane) with low sidelobes and achieves a saturated EIRP of 52 dBm with 4-GHz 3-dB bandwidth. A 300-m wireless link is demonstrated with a record-setting data rate of 8–12 Gb/s over all scan angles using two 64-element TRX arrays and 16-/64-QAM waveforms. [ABSTRACT FROM AUTHOR]

This Letter presents a novel technique for establishing a robust communication link to a spinning un‐stabilised small satellite such as a CubeSat. The authors propose a system that involves a multimode excited planar circular array radio combined with a 360° phase shifter that can electronically track the spinning CubeSat antenna and establish a communication link. The transmitter comprises a mode‐generating Rotman lens and a circular array of microstrip patch antennas. The authors' proposed approach combines two spatially orthogonal modes of the circular array. They first present the system architecture, then they design and realise a proof‐of‐concept experimentally validated module operating in C‐band at 5.8 GHz. [ABSTRACT FROM AUTHOR]

The installation of photovoltaic (PV) systems is gaining great attention due to the matured PV technology and the lowered price of PV modules. With an increasing penetration of PV systems, the selectivity of distribution network protection may be affected which results in undesirable de‐energisation of loads, damage of network equipment, and reduction of reliability. This study presents a method to preserve the protection coordination considering future PV systems installation with any penetration level and different locations along the distribution feeder. Depending on the accessibility of protection device settings or PV control parameters, the proposed method modifies the existing characteristic curve of overcurrent devices or limits the output current of PV sources, respectively. The proposed strategy does not change the structure of existing distribution network protection system and can also be implemented in the old and non‐programmable relays. Meanwhile, it does not need the communication links. The merits of the proposed method are demonstrated through several case studies using the Isfahan distribution network. [ABSTRACT FROM AUTHOR]

This study explores the stabilization problem of nonlinear systems subject to parameter uncertainties, time-varying delay, and data-packet dropouts. An interval type-2 Takagi-Sugenofuzzy model is employed to represent nonlinear systems subject to parameter uncertainties. The lower and upper membership functions of the system enable parameter uncertainties to be captured effectively. To enhance the flexibility of design, the proposed state feedback controller does not share the premise membership functions of the model. Unlike the majority of existing results, the present study simultaneously considers parameter uncertainties, time-varying delay, and data-packet dropouts in nonlinear control systems. A novel finite-sum inequality that includes well-known inequalities as special cases, is developed to derive new stability conditions in the form of linear matrix inequalities. Several examples of simulation are used to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM PUBLISHER]

Event‐triggered control (ETC) is a control strategy in which the control algorithm is executed only when a specific condition is satisfied. Many contributions have been proposed in the ETC literature to reduce the amount of data sent over a communication network. One of the main goals in these methods is reduction of the network bandwidth usage. In this study, a method is proposed to design ET controller which guarantees stability as well as a higher bound on bandwidth requirement. Moreover, the effect of control system on the maximum delay of communication link is explained. Mathematical expression of this effect is presented based on network calculus rules. This yields a method for off‐line fair allocation of bandwidth. Furthermore, a new method is proposed to design a robust controller for norm‐bounded uncertainty which stabilises the control system and guarantees the bandwidth usage and consequently the network delay. To illustrate the effectiveness of the proposed methods, a case study based on the IEEE 802.15.4 protocol is presented which shows the relationship of controller parameters, network parameters, and the delay. [ABSTRACT FROM AUTHOR]