The extended continuous class-F mode RF power amplifier (PA) is presented for the first time. The introduction and experimental validation of this novel PA mode demonstrates a new design space over a wide band of frequencies. This paper will show that high output power and drain efficiency, equivalent to the class-F mode, can be maintained by varying the reactive components of fundamental and second harmonic impedances in accordance with the new formulation of the voltage waveform. Additionally it will be shown that, by varying both phase and magnitude of the fundamental and second harmonic impedances, a yet wider design space can be achieved, where the efficiency is maintained at a level greater than a certain target value. For the validation of this new theory, an experimental investigation was carried out on GaAs pseudomorphic HEMT devices and demonstrates that high output power and drain efficiency between 75%-83% can be achieved over a wide range of fundamental and second harmonic loads.

In this paper, an extended version of the continuous class-F^-1 mode power amplifier (PA) design approach is presented. A new formulation describing the current waveform in terms of just two additional parameters, while maintaining a constant half-wave rectified sinusoidal voltage waveform, allows multiple solutions of fundamental and second-harmonic impedances that provide optimum performance to be computed. By varying only the imaginary parts of fundamental and second-harmonic impedances, it is shown that output performance in terms of power and efficiency is maintained constant and equal to that achievable from the standard class-F^-1 . Indeed, when presenting resistive second-harmonic impedances, it will be demonstrated that the fundamental load can be adjusted to maintain satisfactory output performances greater than a certain predetermined target value. The measurements, conducted on a GaAs pHEMT device at 1 GHz, show a good agreement with the theoretical analysis, revealing drain efficiencies greater than 70% for a very large range of load solutions, which can translate to an ability to accommodate reactive impedance variations with frequency when designing broadband PAs.

The world is rapidly integrating renewable energy resources into the existing grid systems. However, the unpredictable nature of renewables and uncertain load profiles cause issues such as poor power quality, lower system reliability, complex power management, battery degradation, high operating costs, and lower efficiency. Microgrids can help smart grid technology overcome several problems associated with renewable energy integration. Distant locations can obtain electricity without building extensive transmission infrastructure, cutting development costs, or transmission losses. The intermittent nature of renewable energy sources contributes to microgrid problems such as poor power quality, decreased reliability, and high operating costs. Model predictive control (MPC) is an effective method to address challenging industrial and scientific issues. Advancements in MPC that accept different system constraints have solved multiple concerns in uncertain microgrid systems. MPC applied to three hierarchal control layers in a microgrid resolves the problems of power quality, power sharing, energy management, and economic optimization. This study demonstrates that MPC microgrid control is suitable for low-cost operation, improved management, and reliable control. The shortcomings of recent model predictive control techniques for microgrids are reviewed, and future research directions for MPC microgrids are identified.

Physically unclonable functions (PUFs) are recently utilized as a promising security solution for authentication and identification of internet of things (IoT) devices. In this article, we present an efficient implementation of XOR Arbiter PUF (XOR APUF) on field-programmable gate arrays (FPGAs). In our work, we incorporated concept of discrete programmable delays logic (PDL) configurations, the obfuscated challenges and temporal majority voting (TMV) before the XOR operation concurrently to enhance uniqueness and security. The derived design has been verified on 25 Xilinx Artix-7 FPGAs and the results are promising with uniqueness of 48.69%, uniformity 50.73% and reliability 99.41%, which significantly improves over previous work into XOR APUF designs. In addition, we also investigate modeling attack resistance of the proposed design against various modelling attacks and the security analysis show that the proposed PUF has lower prediction rate (< 65%) when compared to the previous XOR APUF designs.

This paper presents a novel approach to reducing undesirable coupling in antenna arrays using custom-designed resonators and inverse surrogate modeling. To illustrate the concept, two standard patch antenna cells with 0.07λ edge-to-edge distance were designed and fabricated to operate at 2.45 GHz. A stepped-impedance resonator was applied between the antennas to suppress their mutual coupling. For the first time, the optimum values of the resonator geometry parameters were obtained using the proposed inverse artificial neural network (ANN) model, constructed from the sampled EM-simulation data of the system, and trained using the particle swarm optimization (PSO) algorithm. The inverse ANN surrogate directly yields the optimum resonator dimensions based on the target values of its S-parameters being the input parameters of the model. The involvement of surrogate modeling also contributes to the acceleration of the design process, as the array does not need to undergo direct EM-driven optimization. The obtained results indicate a remarkable cancellation of the surface currents between two antennas at their operating frequency, which translates into isolation as high as −46.2 dB at 2.45 GHz, corresponding to over 37 dB improvement as compared to the conventional setup.

The unmanned aerial vehicles (UAVs) in military and civilian systems access sensitive data via cellular networks and are ubiquitous. Therefore, the number of handovers may increase, and the process of sharing authentication keys between drones to new drones may be vulnerable to eavesdropping due to the wireless connectivity. For example, a UAV initially served by cell A may be handed over to cell B after a certain point. Therefore, Security and privacy concerns raise if there is a change in the flight path of the UAV due to wide-area connectivity traffic management, including authentication threats as well as the leakage of identity, location, and flying routes. Also, drones are resource-constrained devices that cannot perform extensive operations, leading to the inability to resist drone capture attacks and impersonation attacks. Therefore, this paper presents a high-performance and efficient anonymous handover authentication protocol to secure the drone traveling path. The protocol utilizes the advantages of the AES-RSA algorithm to provide efficient and secure key management and a fast verification and signature generation that speeds up drone authentication. The protocol's security was proved using the formal verification ROR model and automated security verifier ProVerif tool to validate the protocol resistance against various attacks and provided forward secrecy. In addition, the performance of the proposed protocol is evaluated using the OMNeT++ simulator in terms of communication, computation cost, energy consumption, packet drop ratio, end-to-end delay, and throughput. The results showed that the protocol achieves better security, efficiency, and performance than other protocols.