Network's Communication Energy Research Articles

Integrated Data and Energy Communication Network: A Comprehensive Survey

In order to satisfy the power thirst of communication devices in the imminent fifth generation era, wireless charging techniques have attracted much attention both from the academic and industrial communities. Although the inductive coupling and magnetic resonance-based charging techniques are indeed capable of supplying energy in a wireless manner, they tend to restrict the freedom of movement. By contrast, radio frequency (RF) signals are capable of supplying energy over distances, which are gradually inclining closer to our ultimate goal-charging anytime and anywhere. Furthermore, transmitters capable of emitting RF signals have been widely deployed, such as TV towers, cellular base stations, and Wi-Fi access points. This communication infrastructure may indeed be employed also for wireless energy transfer (WET). Therefore, no extra investment in dedicated WET infrastructure is required. However, allowing RF signal-based WET may impair the wireless information transfer (WIT) operating in the same spectrum. Hence, it is crucial to coordinate and balance WET and WIT for simultaneous wireless information and power transfer, which evolves to integrated data and energy communication networks (IDENs). To this end, a ubiquitous IDEN architecture is introduced by summarizing its natural heterogeneity and by synthesizing a diverse range of integrated WET and WIT scenarios. Then the inherent relationship between WET and WIT is revealed from an information theoretical perspective, which is followed by the critical appraisal of the hardware enabling techniques extracting energy from RF signals. Furthermore, the transceiver design, resource allocation, and user scheduling as well as networking aspects are elaborated on. In a nutshell, this treatise can be used as a handbook for researchers and engineers, who are interested in enriching their knowledge base of IDENs and in putting this vision into practice.

Multi-Dimensional Resource Allocation for Uplink Throughput Maximisation in Integrated Data and Energy Communication Networks

The interdisciplinary research of the radio-frequency (RF) signal-based wireless power and information transfer is expected to address the energy shortage issue in the massively deployed low-power Internet of Things devices. Different from conventional wireless powered communication networks (WPCNs), the hybrid base station (H-BS) adopts the simultaneous wireless information and power transfer (SWIPT) for the sake of satisfying the downlink data and energy requests of the multiple user equipments (UEs). The energy harvested from the downlink transmissions can be depleted for supporting the UEs’ uplink transmissions. Integrating SWIPT in the downlink transmission of the WPCN yields a generic integrated data and energy communication network, where the H-BS is equipped with multiple antennas and both the downlink and uplink transmissions are slotted in the time-domain. Furthermore, both the sum-throughput and the fair-throughput of the uplink transmissions are maximized by jointly optimizing the transmit beamformer of the H-BS in the spatial-domain, the time-slot allocation in the time-domain and the signal splitting strategies of the UEs in the power domain, while satisfying the UEs’ minimum downlink transmission requirements. Due to the non-convexity of the problem, a low-complexity successive convex approximation-based algorithm is relied upon for obtaining the optimal resource allocation scheme in the time-domain, power-domain, and spatial-domain. The numerical results validate the efficiency of our proposed resource allocation algorithm and they also demonstrate that supporting low-rate data services during the downlink transmissions does not degrade the wireless power transfer and hence does not reduce the uplink throughput.

An Integrated Fuzzy-Based System for Cluster-Head Selection and Sensor Speed Control in Wireless Sensor Networks

Cluster formation and cluster head selection are important problems in Wireless Sensor Network (WSN) applications and can drastically affect the network's communication energy dissipation. However, selecting the cluster head is not easy in different environments which may have different characteristics. In order to deal with this problem, in this paper, we implement an integrated fuzzy-based system for controlling sensor speed in WSNs. Different from our previous work, we consider 4 input linguistic parameters: Remaining Power of Sensor (RPS), Degree of Number of Neighbor Nodes (D3N), Distance from Cluster Centroid (DCC) and Sensor Speed (SS) for selection of the cluster-head and the control of sensor speed. By controlling the sensor speed, we are able to predict whether the node will leave or stay in the cluster. We evaluate the proposed system by simulations and show that the system has a good behavior.

Frequency Index Modulation for Low Complexity Low Energy Communication Networks

In this paper, we propose a low-complexity multi-user communication system based on frequency index modulation that suits Internet of Things applications. This system aims to reduce the transmitted energy and the peak-to-average-power ratio (PAPR) of orthogonal frequency-division multiplexing (OFDM) systems and to perform without sacrificing data rate in comparison with conventional OFDM. In this design, OFDM-like signals are used to make the implementation of the system easy by the virtue of fast Fourier transform (FFT). In the proposed scheme, an OFDM bandwidth of $N_{\text {FIM}}$ total sub carriers is divided into $N_{B}$ equal number of sub-bands, with $N$ subcarriers in every sub-band. At the transmitter side of each sensor, the outgoing bit stream is divided into two blocks: mapped and modulated. The bits within the mapped block are used to activate the corresponding subcarrier in its predefined sub-band in order to carry the data content of the modulated block, while the other $N-1$ subcarriers are nulled out. At the receiver, the FFT is performed first, and then the square-law envelope detector is applied to estimate the active frequency index to recover the mapped bits, followed by a conventional demodulation process to demodulate the transmitted bits. Once the system is presented and analyzed, energy efficiency, PAPR and complexity are studied to show the features of the proposed scheme. Moreover, we derive closed-form expressions of the bit error rate performance over Rayleigh fading channels and we validate the outcome by simulation results. With the characteristics exhibited in this paper, the proposed system would constitute an excellent candidate for wireless sensor applications where it represents a simpler substitution for frequency-hopping-based architectures, in which the hops carry extra bits.

Event-oriented dynamic security service for demand response in smart grid employing mobile networks

Equipped with millions of sensors and smart meters in smart gird, a reliable and resilient wireless communication technology is badly needed. Mobile networks are among the major energy communication networks which contribute to global energy consumption increase rapidly. As one of core technologies of smart grid employing mobile networks, Demand Response (DR) helps improving efficiency, reliability and security for electric power grid infrastructure. Security of DR events is one of the most important issues in DR. However, the security requirements of different DR events are dynamic for variousactual demands. To address this, an event-oriented dynamic security service mechanism is proposed for DR. Three kinds of security services including security access service, security communication service and security analysis service for DR event are composited dynamically by the fine-grained sub services. An experiment prototype of the network of State Grid Corporation of China (SGCC) is established. Experiment and evaluations shows the feasibility and effectiveness of the proposed scheme in smart grid employing mobile network.

Research of Energy Efficient QoS WSN Routing Protocol Based on Multi-objective Genetic Algorithm

In order to prolong the lifecycle, increase the Quality of Service (QoS) and enlarge the scale of WSNs, a hybrid distance-path routing mechanism was proposed, and the energy e‐cient QoS routing protocol based on multi-objective genetic algorithm was designed. In this protocol, the use of multi-objective genetic algorithm and distance vector updates routing table and optimize network QoS parameters, thus reducing network communication energy consumption, improve the network Quality of Service (QoS); the use of path vector enlarge the scale of WSN. Mathematical analysis and experimental results show that the protocol is e‐cient, the network life cycle was prolonged, the average network transmission delay was reduced, and the network reliability was enhanced.

Performance Evaluation of Two Fuzzy‐Based Cluster Head Selection Systems for Wireless Sensor Networks

Sensor networks supported by recent technological advances in low power wireless communications along with silicon integration of various functionalities are emerging as a critically important computer class that enable novel and low cost applications. There are many fundamental problems that sensor networks research will have to address in order to ensure a reasonable degree of cost and system quality. Cluster formation and cluster head selection are important problems in sensor network applications and can drastically affect the network′s communication energy dissipation. However, selecting of the cluster head is not easy in different environments which may have different characteristics. In this paper, in order to deal with this problem, we propose two fuzzy‐based systems for cluster head selection in sensor networks. We call these systems: FCHS System1 and FCHS System2. We evaluate the proposed systems by simulations and have shown that FCHS System2 make a good selection of the cluster head compared with FCHS System1 and another previous system.