Delta Modulation Technique and Harmonic Analysis for the Modified Quadruple-Diode Boost Regulator Without and With a Voltage Multiplier Unit (VMU) Walid Emar, Ahmad Aljanaideh, Ala Jaber, Mohammad Musleh, Ali Emar, Mohammed Al-Nairat Energies, 2025 The authors of this study suggest an improvement to their recently released quadruple-diode boost regulator (QDBC), which may be used in two configurations: without or with a voltage multiplier unit (VMU). This voltage multiplier unit consists of two switch capacitors diagonally connected across two diodes, or vice versa. During each operational cycle, energy can be stored and released through the switch capacitive filters and inductive chokes, increasing voltage gain and decreasing output fluctuation. ANSOFT/SIMPLORER 7, PLECS 4.9.5, and SIMULINK 2021a are further used to simulate the proposed regulator’s linearized version to investigate its frequency response and stability. Hence, to improve the harmonic performance of the proposed regulator, the authors of this study used a delta modulation current regulator (DMCR), sometimes referred to as a variable bandwidth delta modulation current regulator. The findings show that the QDBC has, when using the DMCR, a voltage gain of 1+D/(1−D)2, an efficiency of 97%, and a shorter settling time of 0.04 s when compared to other DC-DC regulators (SEPIC, boost, and quadratic boost). Finally, to validate the theoretical analysis and simulation results of the proposed QDBC structure, a 250 W regulator prototype was built utilizing similar design exercise requirements.
Improving Connectivity in Urban IoT-Based Wireless Sensor Networks: A Nonorthogonal Cognitive-Based Power Allocation Khalaf M. Bataihah, Haythem Bany Salameh, Haitham Al-Obiedollah, Mohammad Al-Nairat, Yaser Jararweh IEEE Sensors Journal, 2024 Wireless sensor networks (WSNs) have been recently deployed to support various Internet-of-Things (IoT) applications, including sensing in urban environments. Accordingly, several research efforts have been conducted to support the unprecedented massive connectivity requirements, where a massive number of urban sensors are expected to be connected to the Internet. To enable such large-scale urban connectivity, cognitive radio (CR) technology has been identified as an appealing solution. This can be achieved by opportunistically exploiting the under-utilized licensed spectrum. However, most existing CR-based communication protocols were designed under imposing the exclusive-channel occupancy constraint, in which an idle channel cannot be assigned to multiple users at a time. This constraint can significantly limit the number of served sensor devices, which negatively impacts spectral efficiency. This article proposes a batch-based power-controlled nonorthogonal spectrum sharing protocol for CR-enabled WSNs, referred to as the distance-fading factor MAC (DFF-MAC) protocol, aiming to maximize the number of per-channel served transmissions while minimizing the overall transmit power. Specifically, we develop a power-minimization framework, and thus we derive a closed-form expression for the required transmit power for each transmission. This can be achieved by employing a novel multistage power allocation that considers channel gain and interference constraints. Simulation results show that DFF-MAC outperforms the benchmark, namely the exclusive-occupancy protocol, by serving up to three times more transmissions. Furthermore, DFF-MAC achieves a level of performance (in terms of serviced sensors and power consumption) within 4% of the optimal one obtained through exhaustive search while maintaining low complexity.
Convolutionally coded Wideband Code Division Multiple Access in 6G LEO Satellite Communication System Hani Attar, Eman S. Abass, Mohammad Al-Nairat, Ayat Alrosan 1st International Engineering Conference on Electrical Energy and Artificial Intelligence Eiceeai 2022, 2022 The Low Earth Orbit (LEO) network is one of the primary areas of focus for 6G technology. 2020 marked the beginning of 6G research and development, although commercialization may not occur until 2030. LEOs are the ideal choice for 6G due to their lightweight, low cost, and rapid development cycles, which enable them to solve the problem of connectivity in communication-blind places that 5G cannot serve, such as oceans, distant areas, and deserts. This study presents a complete performance evaluation of a convolutionally coded Wideband Code Division Multiple Access (WCDMA) system for the Additive white Gaussian noise (AWGN) channel and the LEO satellite channel. The Bit Error Rate (BER) performance for the proposed system will be formulated and tested using numerical data. Simulation results are demonstrated for a convolutionally coded WCDMA system over an LEO satellite channel for varying numbers of users and coding parameter values. The suggested approach increases the performance of WCDMA-based systems by employing coding gain. Moreover, he results demonstrate that the proposed scheme is superior based on comparing the proposed approach's performance to standard methods without coding.
Discrete OFDM-based channel assignment scheme for agile networks Ali Eyadeh, , Mohammad Al-Nairat, and International Journal on Electrical Engineering and Informatics, 2019 The main goals of all new technologies nowadays are utilizing the available spectrum, increasing spectrum efficiency, and increasing the throughput. Cognitive radio (CR) technology can provide efficient spectrum utilization and maximize the throughput using dynamic spectrum access technique. A new medium access control (MAC) protocol is needed for CR users to access the spectrum dynamically and to maintain fairness between users. In this paper, our objective is to enhance the overall network throughput, by enhancing SMART-V MAC protocol to support D-OFDM technology. A new channel assignment scheme called SMART-O based on these two technologies is proposed. The proposed algorithm greatly increased the overall throughput of the network and solved the channel assignment and rate optimization problems. Simulation results exposed the improvement of our work compared to previous algorithms.
