The smart grid is conceived of as an electric grid that can deliver electricity in a controlled, smart way from points of generation to active consumers. Demand response (DR), by promoting the interaction and responsiveness of the customers, may offer a broad range of potential benefits on system operation and expansion and on market efficiency. Moreover, by improving the reliability of the power system and, in the long term, lowering peak demand, DR reduces overall plant and capital cost investments and postpones the need for network upgrades. In this paper a survey of DR potentials and benefits in smart grids is presented. Innovative enabling technologies and systems, such as smart meters, energy controllers, communication systems, decisive to facilitate the coordination of efficiency and DR in a smart grid, are described and discussed with reference to real industrial case studies and research projects.

Demand response and smart grids—A survey

This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems Draft Amendment: Management Information Base Extensions

With the explosive growth of mobile data demand, the fifth generation (5G) mobile network would exploit the enormous amount of spectrum in the millimeter wave (mmWave) bands to greatly increase communication capacity. There are fundamental differences between mmWave communications and existing other communication systems, in terms of high propagation loss, directivity, and sensitivity to blockage. These characteristics of mmWave communications pose several challenges to fully exploit the potential of mmWave communications, including integrated circuits and system design, interference management, spatial reuse, anti-blockage, and dynamics control. To address these challenges, we carry out a survey of existing solutions and standards, and propose design guidelines in architectures and protocols for mmWave communications. We also discuss the potential applications of mmWave communications in the 5G network, including the small cell access, the cellular access, and the wireless backhaul. Finally, we discuss relevant open research issues including the new physical layer technology, software-defined network architecture, measurements of network state information, efficient control mechanisms, and heterogeneous networking, which should be further investigated to facilitate the deployment of mmWave communication systems in the future 5G networks.

A survey of millimeter wave communications (mmWave) for 5G: opportunities and challenges

Cognitive radio (CR) is the enabling technology for supporting dynamic spectrum access: the policy that addresses the spectrum scarcity problem that is encountered in many countries. Thus, CR is widely regarded as one of the most promising technologies for future wireless communications. To make radios and wireless networks truly cognitive, however, is by no means a simple task, and it requires collaborative effort from various research communities, including communications theory, networking engineering, signal processing, game theory, software-hardware joint design, and reconfigurable antenna and radio-frequency design. In this paper, we provide a systematic overview on CR networking and communications by looking at the key functions of the physical (PHY), medium access control (MAC), and network layers involved in a CR design and how these layers are crossly related. In particular, for the PHY layer, we will address signal processing techniques for spectrum sensing, cooperative spectrum sensing, and transceiver design for cognitive spectrum access. For the MAC layer, we review sensing scheduling schemes, sensing-access tradeoff design, spectrum-aware access MAC, and CR MAC protocols. In the network layer, cognitive radio network (CRN) tomography, spectrum-aware routing, and quality-of-service (QoS) control will be addressed. Emerging CRNs that are actively developed by various standardization committees and spectrum-sharing economics will also be reviewed. Finally, we point out several open questions and challenges that are related to the CRN design.

Cognitive radio networking and communications: an overview

Millimeter wave (mmWave) communications have recently attracted large research interest, since the huge available bandwidth can potentially lead to the rates of multiple gigabit per second per user Though mmWave can be readily used in stationary scenarios, such as indoor hotspots or backhaul, it is challenging to use mmWave in mobile networks, where the transmitting/receiving nodes may be moving, channels may have a complicated structure, and the coordination among multiple nodes is difficult To fully exploit the high potential rates of mmWave in mobile networks, lots of technical problems must be addressed This paper presents a comprehensive survey of mmWave communications for future mobile networks (5G and beyond) We first summarize the recent channel measurement campaigns and modeling results Then, we discuss in detail recent progresses in multiple input multiple output transceiver design for mmWave communications After that, we provide an overview of the solution for multiple access and backhauling, followed by the analysis of coverage and connectivity Finally, the progresses in the standardization and deployment of mmWave for mobile networks are discussed

Millimeter Wave Communications for Future Mobile Networks

An effective resource utilization scheme on cognitive wireless cloud (CWC)-supported multi-hop smart utility network (SUN) applications for radiation dosage surveillance and warning systems to achieve multi-point and long-term monitoring in radioactively contaminated areas by exploiting low-power performance capability is proposed. CWC aims not only to provide a monitoring environment via the Internet, but also to enable dynamic radio resource allocation based on the resource utilization conditions. The computer simulation confirms that an IEEE 802.15.4g/4e-based SUN achieves 60s interval monitoring on a 5 km2 coverage area with a 2 MHz system bandwidth. The paper reports on the practical installation of IEEE 802.15.4g/4e devices in the village of Kawauchi in Fukushima Prefecture.

Resource utilization on CWC-supported long-lived IEEE 802.15.4g/4e SUN for disaster radio

We propose a three-element Yagi-Uda antenna with an inter-element spacing of 0.025 wavelengths for intelligent transport systems (ITS) in the ultra-high frequency (UHF) band. The Yagi-Uda antenna has a reflector dipole with a transmission line at the center. We show by numerical simulation that the antenna can be placed at the contact limit of a vehicle body with improved performance when the transmission line has a meandering configuration. Further, we show by experiment that the actual gain improves by approximately 2 dB when the antenna is placed near a conducting plate.

A compact Yagi-Uda antenna with a transmission line loaded for an ITS in-vehicle terminal in the UHF band

Low Overhead Query Method for the Interface between Geo-Location Database and Secondary User

A 0.4-5.8 GHz SiGe-MMIC quadrature modulator (Q-MOD) employing a self current controlled mixer for cognitive radio is described. The self current controlled mixer consists of a Gilbert cell mixer and a self current control circuit which is composed of both a current feedback circuit and an output buffer amplifier. The self current control circuit automatically controls the mixer current according to the output power level, and improves the linearity over wide radio frequency (RF) range. Simulation results show that the proposed Q-MOD realizes 1 dB compression point (P 1 dB ) improvement of more than 3.0 dB compared to the conventional Q-MOD at the frequencies of 0.4, 0.8, 1.95, 5.2 and 5.8 GHz. The fabricated Q-MOD achieves P 1 dB improvement of more than 2.8 dB under the same condition. It also improves the output power with error vector magnitude (EVM) of 3.0% (P out @EVM=3.0%), and achieves the P out improvement of more than 2.7 dB under the modulation conditions of UHF wireless system (OFDM/16QAM, 0.4GHz), W-CDMA (HPSK/QPSK, 0.8GHz/1.95GHz) and wireless-LAN (OFDM/64QAM, 5.2GHz/5.8GHz).

0.4-5.8 GHz SiGe-MMIC Quadrature Modulator Employing Self Current Controlled Mixer for Cognitive Radio

International Telecommunications Research Institute International (ATR) and Kyoto University (Kyoto Univ.) have jointly promoted a wireless COE (Center of Excellence) program with the support of the Ministry of Internal Affairs and Communications since 2019. The objectives of the program are to create technologies related to resilient radio resource utilization and to accelerate the development of SMEs, start-ups and young talents to lead the wireless technology of the future. In order to achieve the objectives, we have mainly conducted three activities: the concurrent promotion of R&D projects, the construction and operation of open wireless R&D facilities, and the assignment of mentors and their R&D support. Through three-year promotion of the activities with mutual collaboration, we got outcomes and lessons learned. In this paper, we report the overall picture of the program and current status we got through the activities so far.

Hiroshi Harada

Papers

Resource utilization on CWC-supported long-lived IEEE 802.15.4g/4e SUN for disaster radio

A compact Yagi-Uda antenna with a transmission line loaded for an ITS in-vehicle terminal in the UHF band

Low Overhead Query Method for the Interface between Geo-Location Database and Secondary User

0.4-5.8 GHz SiGe-MMIC Quadrature Modulator Employing Self Current Controlled Mixer for Cognitive Radio

An R&D Program to Evolve Resilient Radio Resource Utilization and to Develop SMEs, Start-Ups and Young Talents to Lead Future Wireless Technology