著者
Jian PANG Xueting LUO Zheng LI Atsushi SHIRANE Kenichi OKADA
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E105-C, no.3, pp.102-109, 2022-03-01

This paper introduces a high-resolution and compact CMOS switch-type phase shifter (STPS) for the 5th generation mobile network (5G) n260 band. In this work, totally four coarse phase shifting stages and a high-resolution tuning stage are included. The coarse stages based on the bridged-T topology is capable of providing 202.5° phase coverage with a 22.5° tuning step. To further improve the phase shifting resolution, a compact fine-tuning stage covering 23° is also integrated with the coarse stages. Sub-degree phase shifting resolution is realized for supporting the fine beam-steering and high-accuracy phase calibration in the 5G new radio. Simplified phase control algorithm and suppressed insertion loss can also be maintained by the proposed fine-tuning stage. In the measurement, the achieved RMS gain errors at 39 GHz are 0.1 dB and 0.4 dB for the coarse stages and fine stage, respectively. The achieved RMS phase errors at 39 GHz are 3.1° for the coarse stages and 0.1° for the fine stage. Within 37 GHz to 40 GHz, the measured return loss within all phase-tuning states is always better than -14 dB. The proposed phase shifter consumes a core area of only 0.12mm2 with 65-nm CMOS process, which is area-efficient.
著者
Malathi VEERARAGHAVAN Takehiro SATO Molly BUCHANAN Reza RAHIMI Satoru OKAMOTO Naoaki YAMANAKA
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E100-B, no.11, pp.1978-1991, 2017-11-01
被引用文献数
22

The objectives of this survey are to provide an in-depth coverage of a few selected research papers that have made significant contributions to the development of Network Function Virtualization (NFV), and to provide readers insights into the key advantages and disadvantages of NFV and Software Defined Networks (SDN) when compared to traditional networks. The research papers covered are classified into four categories: NFV Infrastructure (NFVI), Network Functions (NFs), Management And Network Orchestration (MANO), and service chaining. The NFVI papers describe “framework” software that implement common functions, such as dynamic scaling and load balancing, required by NF developers. Papers on NFs are classified as offering solutions for software switches or middleboxes. MANO papers covered in this survey are primarily on resource allocation (virtual network embedding), which is an orchestrator function. Finally, service chaining papers that offer examples and extensions are reviewed. Our conclusions are that with the current level of investment in NFV from cloud and Internet service providers, the promised cost savings are likely to be realized, though many challenges remain.
著者
Kazunori HAYASHI Masaaki NAGAHARA Toshiyuki TANAKA
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E96-B, no.3, pp.685-712, 2013-03-01
被引用文献数
177

This survey provides a brief introduction to compressed sensing as well as several major algorithms to solve it and its various applications to communications systems. We firstly review linear simultaneous equations as ill-posed inverse problems, since the idea of compressed sensing could be best understood in the context of the linear equations. Then, we consider the problem of compressed sensing as an underdetermined linear system with a prior information that the true solution is sparse, and explain the sparse signal recovery based on 1 optimization, which plays the central role in compressed sensing, with some intuitive explanations on the optimization problem. Moreover, we introduce some important properties of the sensing matrix in order to establish the guarantee of the exact recovery of sparse signals from the underdetermined system. After summarizing several major algorithms to obtain a sparse solution focusing on the 1 optimization and the greedy approaches, we introduce applications of compressed sensing to communications systems, such as wireless channel estimation, wireless sensor network, network tomography, cognitive radio, array signal processing, multiple access scheme, and networked control.
著者
Colin G. Harrison
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE Transactions on Communications (ISSN:09168516)
巻号頁・発行日
pp.2017ADI0003, (Released:2018-02-22)
被引用文献数
1

As the capabilities and costs of Artificial Intelligence (AI) and of sensors (IoT) continue to improve, the concept of a "control system" can evolve beyond the operation of a discrete technical system based on numerical information and enter the realm of large-scale systems with both technical and social characteristics based on both numerical and unstructured information. This evolution has particular significance for applying the principles of Autonomous Decentralised Systems (ADS) [1]. This article considers the possible roles for ADS in complex technical and social systems extending up to global scales.
著者
MIN Byongseok KIM Seungjong MANDAL Mrinal JEONG Jechang
出版者
一般社団法人電子情報通信学会
雑誌
IEICE transactions on communications (ISSN:09168516)
巻号頁・発行日
vol.88, no.8, pp.3443-3450, 2005-08-01
被引用文献数
1

Animation video is becoming very popular with the availability of low cost computing resources. The cell animation is a popular method, used for producing animation video. In order to efficiently encode these videos, conventional video codecs, such as AutoDesk Animation Pro FLC, Intel Indeo 5, and MPEG-4 can be used to achieve high compression. However, when cell animation videos are compressed at very low bit rate by these traditional codecs, objectionable artifacts, e.g., false color, blurred contours, and blocking artifact, are severely occurred. In this paper, we propose an efficient compression method for cell animation images. The proposed method employs hybrid coding scheme which includes intraframe and interframe coding modes. The intraframe mode consists of color quantization, adaptive differential pulse code modulation, forward classification, and Golomb-Rice coding. The interframe coding consists of block-based techniques and exploits the characteristics of motion. Simulation results show that the proposed method provides superior performance over AutoDesk Animation Pro FLC, MPEG-1, Intel Indeo 5, and MPEG-4 standards.
著者
KOIKE Arata
出版者
一般社団法人電子情報通信学会
雑誌
IEICE transactions on communications (ISSN:09168516)
巻号頁・発行日
vol.84, no.8, pp.2105-2114, 2001-08-01
参考文献数
18
被引用文献数
1

Using Available Bit Rate (ABR) service of Asynchronous Transfer Mode (ATM) at a backbone link will provide a lossless network. It, however, causes congestion at an edge-router and is reported to show poor end-to-end TCP performance. We consider how to improve the performance of TCP over a backbone ABR network. By using ABR feedback information (ACR) at edge-routers, we can adjust intervals of TCP Acknowledgement packets. This adjustment couples the ABR rate-based control loop and the TCP window-based control loop. Based on this scheme, we can achieve a good end-to-end TCP performance as well as good ATM layer performance over backbone ABR. This paper describes comprehensive study on the proposed mechanism.
著者
Takayuki SUYAMA
出版者
一般社団法人 電子情報通信学会
雑誌
IEICE Transactions on Communications (ISSN:09168516)
巻号頁・発行日
vol.E99.B, no.9, pp.1930-1937, 2016-09-01 (Released:2016-09-01)
参考文献数
17
被引用文献数
3

To help elderly and physically disabled people to become self-reliant in daily life such as at home or a health clinic, we have developed a network-type brain machine interface (BMI) system called “network BMI” to control real-world actuators like wheelchairs based on human intention measured by a portable brain measurement system. In this paper, we introduce the technologies for achieving the network BMI system to support activities of daily living.
著者
KAWAKITA Yuusuke ICHIKAWA Haruhisa
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE Transactions on Communications (ISSN:09168516)
巻号頁・発行日
vol.97, no.9, pp.1800-1807, 2014
被引用文献数
2

Wide area virtualization of wireless transceivers by centrally managed software radio systems is a way to efficiently share the resources for supporting a variety of wireless protocols. In order to enable wide-area virtualization of wireless transceivers, the authors have developed a mechanism to deliver the radio space information which is quantized broadband radio wave information including the radio signals to the transceivers. Delivery mechanism consists of a distribution server which distributes radio space corresponding to the request of the client such as the center frequency and the bandwidth and a client which uses the radio space information. Accumulation of the distribution servers which deliver radio space information simultaneously to a large number of clients will contribute to build an infrastructure for any clients ubiquitously distributed over the globe. In this paper, scale-out architecture of a distribution server is proposed to deliver unlimitedly broadband radio space information to unlimited number of clients. Experimental implementation indicates the architecture to be a scale-out solution, while the number of clients is restricted by the computer resources of the distribution server. The band pass filter processing for individual client in the distribution server consumes the dominant part of the processing power, and the number of CPU cores is the upper limit of clients supportable for the distribution server in the current operating system implementation. The logical increase of the number of CPU cores by hardware multithreading does not contribute to relax this limit. We also discuss the guidance architecture or building server derived from these conclusions.
著者
Junichi KINOSHITA Yoshihisa IKEDA Yuji TAKEDA
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E96-C, no.11, pp.1391-1398, 2013-11-01
被引用文献数
8

Ultra-high luminance lamps emitting white light with a well-scattered blue spectrum from InGaN/GaN laser diodes and a phosphor-converted yellow spectrum show speckle contrast values as low as LED. Spectral behavior of the laser diodes is analyzed to find the reason why such low values are obtained. As a result, the PWM-driven, multi-longitudinal mode with dynamically broadened line-width is found to have a great effect on reducing speckle contrast. Despite using the lasers, such speckle-free lamps are considered to be very suitable for high-luminance and other various lighting applications.
著者
Kazuya SUZUKI Kentaro SONODA Nobuyuki TOMIZAWA Yutaka YAKUWA Terutaka UCHIDA Yuta HIGUCHI Toshio TONOUCHI Hideyuki SHIMONISHI
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E97-B, no.2, pp.375-386, 2014-02-01

The paper presents a survey on OpenFlow related technologies that have been proposed as a means for researchers, network service creators, and others to easily design, test, and deploy their innovative ideas in experimental or production networks to accelerate research activities on network technologies. Rather than having programmability within each network node, separated OpenFlow controllers provide network control through pluggable software modules; thus, it is easy to develop new network control functions in executable form and test them in production networks. The emergence of OpenFlow has started various research activities. The paper surveys these activities and their results.
著者
NIIDA Sumaru UEMURA Satoshi HARADA Etsuko T.
出版者
電子情報通信学会
雑誌
IEICE transactions on communications (ISSN:09168516)
巻号頁・発行日
vol.E96-B, no.8, pp.2069-2075, 2013-08
被引用文献数
2

As mobile multimedia services expand, user behavior will become more diverse and the control of service quality from the user's perspective will become more important in service design. The quality of the network is one of the critical factors determining mobile service quality. However, this has mainly been evaluated in objective physical terms, such as delay reduction and bandwidth expansion. It is less common to use a human-centered design viewpoint when improving network performance. In this paper, we discuss ways to improve the quality of web services using time-fillers that actively address the human factors to improve the subjective quality of a mobile network. A field experiment was conducted, using a prototype. The results of the field experiment show that time-fillers can significantly decrease user dissatisfaction with waiting, but that this effect is strongly influenced by user preferences concerning content. Based on these results, we discuss the design requirements for effective use of time-fillers.
著者
Masayuki HIRATA Kojiro MATSUSHITA Takafumi SUZUKI Takeshi YOSHIDA Fumihiro SATO Shayne MORRIS Takufumi YANAGISAWA Tetsu GOTO Mitsuo KAWATO Toshiki YOSHIMINE
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E94-B, no.9, pp.2448-2453, 2011-09-01

The brain-machine interface (BMI) is a new method for man-machine interface, which enables us to control machines and to communicate with others, without input devices but directly using brain signals. Previously, we successfully developed a real time control system for operating a robot arm using brain-machine interfaces based on the brain surface electrodes, with the purpose of restoring motor and communication functions in severely disabled people such as amyotrophic lateral sclerosis patients. A fully-implantable wireless system is indispensable for the clinical application of invasive BMI in order to reduce the risk of infection. This system includes many new technologies such as two 64-channel integrated analog amplifier chips, a Bluetooth wireless data transfer circuit, a wirelessly rechargeable battery, 3 dimensional tissue-fitting high density electrodes, a titanium head casing, and a fluorine polymer body casing. This paper describes key features of the first prototype of the BMI system for clinical application.
著者
Peijian ZHANG Kunfeng ZHU Wensuo CHEN
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E107-C, no.1, pp.12-17, 2024-01-01

In this paper, a novel trench MOS barrier Schottky contact super barrier rectifier (TMB-SSBR) is proposed by combining the advantages of vertical SSBR and conventional TMBS. The operation mechanism and simulation verification are presented. TMB-SSBR consists of MOS trenches with a vertical SSBR grid which replaces the Schottky diode in the mesa of a TMBS. Due to the presence of top p-n junction in the proposed TMB-SSBR, the image force barrier lowering effect is eliminated, the pinching off electric field effect by MOS trenches is weakened, so that the mesa surface electric field is much larger than that in conventional TMBS. Therefore, the mesa width is enlarged and the n-drift concentration is slightly increased, which results in a low specific on-resistance and a good tradeoff between reverse leakage currents and forward voltages. Compared to a conventional TMBS, simulation results show that, with the same breakdown voltage of 124V and the same reverse leakage current at room temperature, TMB-SSBR increases the figure of merit (FOM, equates to VB2/Ron, sp) by 25.5%, and decreases the reverse leakage by 33.3% at the temperature of 423K. Just like the development from SBD to TMBS, from TMBS to TMB-SSBR also brings obvious improvement of performance.
著者
Longle CHENG Xiaofeng LI Haibo TAN He ZHAO Bin YU
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E107-B, no.1, pp.185-196, 2024-01-01

Blockchain systems rely on peer-to-peer (P2P) overlay networks to propagate transactions and blocks. The node management of P2P networks affects the overall performance and reliability of the system. The traditional structure is based on random connectivity, which is known to be an inefficient operation. Therefore, we propose MSLT, a multiscale blockchain P2P network node management method to improve transaction performance. This approach involves configuring the network to operate at multiple scales, where blockchain nodes are grouped into different ranges at each scale. To minimize redundancy and manage traffic efficiently, neighboring nodes are selected from each range based on a predetermined set of rules. Additionally, a node updating method is implemented to improve the reliability of the network. Compared with existing transmission models in efficiency, utilization, and maximum transaction throughput, the MSLT node management model improves the data transmission performance.
著者
Aditya RAKHMADI Kazuyuki SAITO
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E106-C, no.12, pp.799-807, 2023-12-01

Transcatheter renal denervation (RDN) is a novel treatment to reduce blood pressure in patients with resistant hypertension using an energy-based catheter, mostly radio frequency (RF) current, by eliminating renal sympathetic nerve. However, several inconsistent RDN treatments were reported, mainly due to RF current narrow heating area, and the inability to confirm a successful nerve ablation in a deep area. We proposed microwave energy as an alternative for creating a wider ablation area. However, confirming a successful ablation is still a problem. In this paper, we designed a prediction method for deep renal nerve ablation sites using hybrid numerical calculation-driven machine learning (ML) in combination with a microwave catheter. This work is a first-step investigation to check the hybrid ML prediction capability in a real-world situation. A catheter with a single-slot coaxial antenna at 2.45 GHz with a balloon catheter, combined with a thin thermometer probe on the balloon surface, is proposed. Lumen temperature measured by the probe is used as an ML input to predict the temperature rise at the ablation site. Heating experiments using 6 and 8 mm hole phantom with a 41.3 W excited power, and 8 mm with 36.4 W excited power, were done eight times each to check the feasibility and accuracy of the ML algorithm. In addition, the temperature on the ablation site is measured for reference. Prediction by ML algorithm agrees well with the reference, with a maximum difference of 6°C and 3°C in 6 and 8 mm (both power), respectively. Overall, the proposed ML algorithm is capable of predicting the ablation site temperature rise with high accuracy.
著者
Atsushi TAGAMI Takuya MIYASAKA Masaki SUZUKI Chikara SASAKI
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E106-B, no.12, pp.1267-1274, 2023-12-01
被引用文献数
1

Recently, there has been a surge of interest in Artificial Intelligence (AI) and its applications have been considered in various fields. Mobile networks are becoming an indispensable part of our society, and are considered as one of the promising applications of AI. In the Beyond 5G/6G era, AI will continue to penetrate networks and AI will become an integral part of mobile networks. This paper provides an overview of the collaborations between networks and AI from two categories, “AI for Network” and “Network for AI,” and predicts mobile networks in the B5G/6G era. It is expected that the future mobile network will be an integrated infrastructure, which will not only be a mere application of AI, but also provide as the process infrastructure for AI applications. This integration requires a driving application, and the network operation is one of the leading candidates. Furthermore, the paper describes the latest research and standardization trends in the autonomous networks, which aims to fully automate network operation, as a future network operation concept with AI, and discusses research issues in the future mobile networks.
著者
Chris MANGELSDORF
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E106-C, no.10, pp.516-520, 2023-10-01

Recent years have seen a decline in the art of analog IC design even though analog interface and analog signal processing remain just as essential as ever. While there are many contributing factors, four specific pressures which contribute the most to the loss of creativity and innovation within analog practice are examined: process evolution, risk aversion, digitally assisted analog, and corporate culture. Despite the potency of these forces, none are found to be insurmountable obstacles to reinvigorating the industry. A more creative future is within our reach.
著者
Xiaohu WANG Yubin DUAN Yi WEI Xinyuan CHEN Huang ZHUN Chaohui ZHAO
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E106-B, no.11, pp.1102-1108, 2023-11-01

With the gradually increase of the application of new energy in microgrids, Electric Spring (ES), as a new type of distributed compensation power electronic device has been widely studied. The Generalized Electric Spring (G-ES) is an improved topology, and the space limitation problem in the traditional topology is solved. Because of the mode of G-ES use in the power grid, a reasonable solution to the voltage loss of the critical section feeder is needed. In this paper, the voltage balance equation based on the feedforward compensation coefficient is established, and a two cascade control strategy based on the equation is studied. The first stage of the two cascade control strategy is to use communication means to realize the allocation of feedforward compensation coefficients, and the second stage is to use the coefficients to realize feedforward fixed angle control. Simulation analysis shows that the proposed control strategy does not affect the control accuracy of the critical load (CL), and effectively improves the operational range of the G-ES.
著者
Xiaoman LIU Yujie GAO Yuan HE Xiaohan YUE Haiyan JIANG Xibo WANG
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Electronics (ISSN:09168516)
巻号頁・発行日
vol.E106-C, no.10, pp.570-579, 2023-10-01

The complexity and scale of Networks-on-Chip (NoCs) are growing as more processing elements and memory devices are implemented on chips. However, under strict power budgets, it is also critical to lower the power consumption of NoCs for the sake of energy efficiency. In this paper, we therefore present three novel input unit designs for on-chip routers attempting to shrink their power consumption while still conserving the network performance. The key idea behind our designs is to organize buffers in the input units with characteristics of the network traffic in mind; as in our observations, only a small portion of the network traffic are long packets (composed of multiple flits), which means, it is fair to implement hybrid, asymmetric and reconfigurable buffers so that they are mainly targeting at short packets (only having a single flit), hence the smaller power consumption and area overhead. Evaluations show that our hybrid, asymmetric and reconfigurable input unit designs can achieve an average reduction of energy consumption per flit by 45%, 52.3% and 56.2% under 93.6% (for hybrid designs) and 66.3% (for asymmetric and reconfigurable designs) of the original router area, respectively. Meanwhile, we only observe minor degradation in network latency (ranging from 18.4% to 1.5%, on average) with our proposals.
著者
Meng-Yuan HE Ling-Yun JIANG
出版者
The Institute of Electronics, Information and Communication Engineers
雑誌
IEICE TRANSACTIONS on Communications (ISSN:09168516)
巻号頁・発行日
vol.E106-B, no.10, pp.881-890, 2023-10-01

In the current heterogeneous wireless communication system, the sharp rise in energy consumption and the emergence of new service types pose great challenges to nowadays radio access network selection algorithms which do not take care of these new trends. So the proposed energy efficiency based multi-service heterogeneous access network selection algorithm-ESRS (Energy Saving Radio access network Selection) is intended to reduce the energy consumption caused by the traffic in the mobile network system composed of Base Stations (BSs) and Access Points (APs). This algorithm models the access network selection problem as a Multiple-Attribute Decision-Making (MADM) problem. To solve this problem, lots of methods are combined, including analytic Hierarchy Process (AHP), weighted grey relational analysis (GRA), entropy theory, simple additive weight (SAW), and utility function theory. There are two main steps in this algorithm. At first, the proposed algorithm gets the result of the user QoS of each network by dealing with the related QoS parameters, in which entropy theory and AHP are used to determine the QoS comprehensive weight, and the SAW is used to get each network's QoS. In addition to user QoS, parameters including user throughput, energy consumption utility and cost utility are also calculated in this step. In the second step, the fuzzy theory is used to define the weight of decision attributes, and weighted grey relational analysis (GRA) is used to calculate the network score, which determines the final choice. Because the fuzzy weight has a preference for the low energy consumption, the energy consumption of the traffic will be saved by choosing the network with the least energy consumption as much as possible. The simulation parts compared the performance of ESRS, ABE and MSNS algorithms. The numerical results show that ESRS algorithm can select the appropriate network based on the service demands and network parameters. Besides, it can effectively reduce the system energy consumption and overall cost while still maintaining a high overall QoS value and a high system throughput, when compared with the other two algorithms.