CNN‐based architecture for real‐time object‐oriented video coding applications

This paper presents a new CNN‐based architecture for real‐time video coding applications. The proposed approach, by exploiting object‐oriented CNN algorithms and MPEG encoding capabilities, enables low bit‐rate encoder/decoder to be designed. Simulation results using Claire video sequence show the effectiveness of the proposed scheme. Copyright © 2005 John Wiley & Sons, Ltd.     

CMT‐CQA: Cross‐layer QoS‐aware adaptive concurrent multipath data transfer in heterogeneous networks

Stream control transport protocol (SCTP)‐based concurrent multipath transfer (CMT) can help multi‐homed devices to increase their throughput by making use of parallel transmissions over multiple paths and bandwidth aggregation. However, if CMT cannot identify wireless error, it cannot really achieve the desired performance. Furthermore, if CMT only utilizes all available paths for data delivery, it will undoubtedly degrade application‐level performance since the asymmetric paths may involve large quality differences. This paper proposes a novel cross‐layer quality‐of‐service (QoS)‐aware adaptive CMT (CMT‐CQA) with the following aims: (i) to provide an adaptive ‘CMT‐to‐partial CMT’ adjustment strategy for efficient bandwidth aggregation by jointly considering transport layer QoS, MAC layer QoS, and path history information; (ii) to address an enhanced congestion window (cwnd) fast recovery mechanism to reduce bursty transmission in multi‐homed wireless network environments where fail‐over occurs frequently; and (iii) to introduce a proper multimedia transmission behavior to improve users' quality of experience (QoE) for multimedia streaming service. Simulation results show that CMT‐CQA outperforms the existing CMT solutions in terms of performance and QoS. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Low complexity M‐PPM impulse‐radio ultra wideband over fiber system for wireless sensor networks applications

Ultra wideband over fiber (UWBoF) systems have been proposed to extend wireless range and to interconnect stand‐alone UWB networks. These systems have focused on high‐data‐rate applications. However, UWB will be a key enabler for low‐data‐rate wireless sensor network (WSN) deployments. In this letter, a low‐cost and low‐complexity M‐ary pulse position modulation (PPM) impulse radio (IR)‐UWBoF system designed for WSNs applications is proposed. A spectral line‐suppressive convolutional code is used to achieve spectral line suppression in the power spectral density (PSD). Experimental results show that the system does not distort or add spectral lines to the IR‐UWB signal PSD transmitted over 30 km of a single‐mode fiber, thus demonstrating its feasibility to interconnect WSN deployments. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

An energy‐efficient cooperative MIMO transmission with data compression in wireless sensor networks

In this letter, a novel metric for energy‐efficient cooperative transmission with data compression in wireless sensor networks (WSNs) is proposed. Under the guidance of the new metric, energy consumption is optimized by considering the correlation between data generated by the sensor nodes. The distance between sensor nodes inside the cluster affecting the data correlation as a key factor is analyzed, and the corresponding optimal value is used to reduce the energy consumption. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Design and analysis of power‐CMOS‐gate‐based switched‐capacitor DC–DC converter with step‐down and step‐up modes

A unified multi‐stage power‐CMOS‐transmission‐gate‐based quasi‐switched‐capacitor (QSC) DC–DC converter is proposed to integrate both step‐down and step‐up modes all in one circuit configuration for low‐power applications. In this paper, by using power‐CMOS‐transmission‐gate as a bi‐directional switch, the various topologies for step‐down and step‐up modes can be integrated in the same circuit configuration, and the configuration does not require any inductive elements, so the IC fabrication is promising for realization. In addition, both large‐signal state‐space equation and small‐signal transfer function are derived by state‐space averaging technique, and expressed all in one unified formulation for both modes. Based on the unified model, it is all presented for control design and theoretical analysis, including steady‐state output and power, power efficiency, maximum voltage conversion ratio, maximum power efficiency, maximum output power, output voltage ripple percentage, capacitance selection, closed‐loop control and stability, etc. Finally, a multi‐stage QSC DC–DC converter with step‐down and step‐up modes is made in circuit layout by PSPICE tool, and some topics are discussed, including (1) voltage conversion, output ripple percentage, and power efficiency, (2) output robustness against source noises and (3) regulation capability of converter with loading variation. The simulated results are illustrated to show the efficacy of the unified configuration proposed. Copyright © 2003 John Wiley & Sons, Ltd.     

多模式无线视频码流的传输与控制

采用快速传送协议/用户数据报协议/IP方式实现了多模式无线网络（WLAN、GPRS、CDMA）的码流传输,并完成无线通信下的RTCP双向控制信息链路.针对无线IP网络的传输特性,选取了适当的QoS参数反馈控制传输质量.实验测试表明,多模式无线通信系统下的码流传输在接收端取得了较好的视频传输质量.     

Watermarking on CNN‐UM for image and video authentication

In this paper a new approach to fragile watermarking technique is introduced. This problem is particularly interesting in the field of modern multimedia applications, when image and video authentication are required. The approach exploits the cellular automata suitability to work as pseudorandom pattern generators and extends the related algorithms under the framework of the cellular non‐linear networks (CNNs). The result is a novel way to perform watermarking generation in real time, using the presently available CNN‐universal chip prototypes. In this paper, both the CNN algorithms for fragile watermarking as well as on‐chip experimental results are reported, confirming the suitability of CNNs to successfully act as real‐time watermarking generators. The availability of CNN‐based visual microprocessors allows to have powerful algorithms to watermark in real time images or videos for efficient smart camera applications. Copyright © 2004 John Wiley & Sons, Ltd.     

Predictive call admission control for multimedia streaming in CDMA cellular environments

Third-generation (3G) wireless networks based on code-division multiple access (CDMA) have been engineered to provide mobile users with voice as well as advanced packet data services. Support of Internet-based multimedia streaming services is considered a critical factor for future deployment of such networks. Provisioning streaming services in a dependable way, however, requires supporting data transmission at relatively high data rates while maintaining session quality during both intracell and intercell user movements. In this paper, an adaptive bandwidth allocation and admission control scheme is proposed for managing network resources for a streaming service. Streaming requests are assumed to be served by an adaptive server capable of choosing suitable video streaming parameters (e.g., video resolution, frame rate, and encoding parameters) in response to possible requests from the wireless network to vary the currently allocated bandwidth. The devised admission control scheme exploits a priori knowledge of user mobility patterns to minimize the risk of running into an overload condition after acceptance of a new multimedia streaming connection. The obtained simulation results show that, compared to a nonpredictive admission control scheme, the proposed scheme achieves a lower forced-termination probability and higher throughput, while consuming less base-station transmission energy.     

Design and optimization of a 3‐coil resonance‐based wireless power transfer system for biomedical implants

This paper presents a resonance‐based wireless power transfer system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. We theoretically analyzed the system and characterized it by measuring its inductance, self‐resonant frequency, and quality factor Q. In our resonance‐based wireless power transfer prototype, we proposed a 3‐coil system, using two 15‐mm radius implantable coils, with a resonance frequency of 6.76 MHz. This system can effectively transfer power for a distance of up to 50 mm. Moreover, our proposed 3‐coil system can achieve a high Q‐factor and has a comparable power transfer efficiency (PTE) to previously reported works about 3‐coil and 4‐coil systems. The experimental PTE can achieve 82.4% at a separation distance of 20 mm and more than 10% PTE at a distance of 40 mm. Copyright © 2014 John Wiley & Sons, Ltd.     

Energy Efficient System-on-chip Design for Wireless Body Area Sensor Network

This article presents a novel energy-efficient on-chip design for wireless body area sensor networks focused towards pervasive healthcare applications. The network adopts a master–slave architecture, where the body-worn slave nodes periodically send sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this wireless body area sensor networks are not deployed in an ad hoc fashion. The network is centrally managed and all communications are single-hop. A cluster algorithm is also presented so that all slave nodes are within the transmission range of the master nodes. It pretends that all slave nodes can share resources and information over the internet to reduce energy consumption. The design on system-on-chip platform has been simulated for some experiments and implemented. Compared to published and industrially used schemes, the power consumption of the proposed design is over 30 and 99% lower in the simulation and platform implementation, respectively.     

An intelligent MPEG rate control in 2.4 GHz frequency

Transmitting Moving Picture Expert Group (MPEG) Variable Bit Rate (VBR) video stream over 2.4 GHz wireless frequency demands a large bandwidth and may result in data loss and delay, because of excessive fluctuation in bit rate. Transmission over 2.4 GHz frequency further causes uncertainty due to interferences by other wireless devices in the same frequency band and/or common dynamic channel noises. As a result, an intelligent system has been developed for MPEG video transmission over 2.4 GHz frequency band. A novel fuzzy controller automatically determines the quantization scale for each Group Of Picture (GOP) of the encoder during the transmission period. Moreover, a fuzzy controller and a neural‐fuzzy controller stream the MPEG video data to conform to the current condition of dynamic wireless channel to maintain image quality during the transmission. In the intelligent system, rather than choosing the parameters associated with a given membership function arbitrarily, these parameters are chosen as such to tailor the membership functions to the desired input/output data. The intelligent system computes and trains the system in such a way that its output will be equal to the desired value. Computer simulation results demonstrate that the proposed intelligent technique increases transmission rate and reduces data loss, excessive delay and image quality degradation as compared with a conventional video transmission over 2.4 GHz frequency band. Copyright © 2009 John Wiley & Sons, Ltd.     

An accurate time‐domain model of transmission lines with frequency‐dependent parameters

Linear lossy two‐conductor transmission line can be modelled as dynamic two ports in the time domain, via the describing input and transfer impulse responses. This convolution technique is very effective when dealing with networks composed of transmission lines with frequency‐dependent parameters and non‐linear and/or time‐varying circuits. The paper carries out an accurate analysis of this model, in the most general case of lines with frequency‐dependent parameters. For such lines it is not possible to evaluate analytically the impulse responses, nor is it possible to catch them numerically, due to the presence of irregular terms, such as Dirac pulses, terms that numerically behave as Dirac pulses, and functions of the type 1/t^ρ with 0 < ρ <1. A simple method is proposed to evaluate exactly all the irregular terms of the impulse responses: once these irregular parts have been extracted, the regular remainders are easily evaluated numerically. This method is applied to analyse lines with frequency‐dependent parameters of practical interest, such as superconductor transmission lines, power lines above a finite conductivity ground, lines with frequency‐dependent dielectric losses and lines with normal and anomalous skin‐effect. Numerical simulations are carried out for illustration. Copyright © 2000 John Wiley & Sons, Ltd.     

High‐throughput IDCT architecture for high‐efficiency video coding (HEVC)

This paper presents a hardware design capable of supporting high‐efficiency video coding inverse discrete cosine transform (IDCT) with a 32×32 transform unit size, using a single 1‐D IDCT core with transpose memory to reduce costs. The proposed 1‐D IDCT core employs 16 computation paths for high throughput and is implemented using distributed arithmetic to facilitate the sharing of hardware resources. The proposed 1‐D IDCT is capable of calculating 1‐D and 2‐D data simultaneously along 32 parallel paths. When implemented using Taiwan Semiconductor Manufacturing Company (TSMC) 40‐nm CMOS technology, the proposed 2‐D transform core provides throughput of 6.4 gigapixels/s with a gate count of 335 k. The results show that a superior hardware efficiency can be achieved in the proposed 32‐point IDCT core compared with the existing works. Copyright © 2017 John Wiley & Sons, Ltd.     

Low‐latency retransmission control in a wireless communication system for plant instrumentation and control

When wireless communication technology is applied to plant instrumentation and control systems, it is important to ensure real‐time transmission and high reliability of the wireless communication system. However, the wireless communication system is prone to more frequent occurrence of transmission errors than a wired communication system, so that generally retransmission is implemented generically. To reduce retransmission latency, we propose a method of low‐latency retransmission control, which is a data block transmission method with multi‐redundant media access control layer (MAC) headers, to implement a wireless communication system for plant instrumentation and control. We carried out system tests using prototypes with the proposed methods, that is, data block transmission with multi‐redundant MAC headers. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A noise‐constrained algorithm for estimation over distributed networks

Much research has been devoted recently to the development of algorithms to utilize the distributed structure of an ad hoc wireless sensor network for the estimation of a certain parameter of interest. A successful solution is the algorithm called the diffusion least mean squares algorithm. The algorithm estimates the parameter of interest by employing cooperation between neighboring sensor nodes within the network. The present work derives a new algorithm by using the noise constraint that is based on and improves the diffusion least mean squares algorithm. In this work, first the derivation of the noise constraint‐based algorithm is given. Second, detailed convergence and steady‐state analyses are carried out, including analyses for the case where there is mismatch in the noise variance estimate. Finally, extensive simulations are carried out to test the robustness of the proposed algorithm under different scenarios, especially the mismatch scenario. Moreover, the simulation results are found to corroborate the theoretical results very well. Copyright © 2012 John Wiley & Sons, Ltd.     

基于GPRS网络远程抄表系统的设计

简要介绍了GPRS技术和自组织网络的特点，设计了一种基于GPRS技术的网络抄表系统。通过GPRS网络实现远程数据的采集和传输，具体说明了系统的结构、工作原理和相关的技术，并分析了系统硬件和软件的性能及其优、缺点。该系统具有传输速率高，数据吞吐量大，通信实时，可靠性高等优点。该系统在仪器仪表的远程监控及数据的遥控遥测方面具有很高的参考和使用价值。     

Wireless power charger for wearable medical devices with in‐band communication

A wireless power charger integrated circuit has been developed for wearable medical devices in a 0.18‐µm Bipolar, Complementary metal‐oxide‐semiconductor, and Lightly‐Doped Metal‐Oxide‐Semiconductor (BCDMOS) process. A passive full‐wave rectifier consisting of Schottky diodes and cross‐coupled n‐type Metal‐Oxide‐Semiconductor (nMOS) transistors performs the alternating current to direct current power conversion without any reverse leakage current. To charge a battery, a linear charger circuit follows the passive rectifier instead of a switching charger circuit for the small form factor of wearable medical devices. An in‐band communication circuit notifies the proper connection of the wireless power receiver and the battery charging status to the charging pad (wireless power transmitter) through the wireless power transmission channel. The wireless power charger integrated circuit occupies 1.44‐mm² silicon area and shows 31.7% power efficiency when the charging current is 26.6 mA. Copyright © 2015 John Wiley & Sons, Ltd.     

Stackable ROADM with optical amplifier for use in IP‐Over‐CWDM ring networks

A stackable module with a bidirectional coarse wavelength division multiplexing (CWDM) amplifier is proposed to introduce the optical amplifier into an stackable‐reconfigurable optical add/drop multiplexers (S‐ROADM) for use in an IP‐over‐CWDM ring network, and the performance is evaluated experimentally. Packet transfer changes are monitored during the lightpath reconfiguration, which needs optical amplification. The result clarify that the lightpaths are reconfigured successfully, including the remote activation of the amplifiers. As a result, the stackable feature of the amplifier module enables us to provide a cost‐effective introduction into the network on an implement‐it‐when‐necessary base in a fully compatible way with the existing S‐ROADM modules when constructing the S‐ROADM with an amplifier. Therefore, the amplifier module can be used in the same way as the ROADM modules to construct the S‐ROADM, providing manually adding capability of the amplifier to in‐service networks. Thus, the amplifier module has a big advantage to use it flexibly and economically in the IP‐over‐CWDM ring networks. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

视频抗误码技术在无线网络中的应用研究

随着第3代移动通信的发展,基于无线的视频抗误码技术成为多媒体通信领域研究的热点之一。以H.263视频编码标准为基础,根据实时视频传输的特点,提出2种可用于无线的视频抗误码技术,即基于反馈的帧内刷新和插入重同步标识。经CDMA2000 1x网络的测试,这2种方法在少量增加编码比特率的情况下,能较大程度地改善因传输误码而引起的视频质量恶化情况,适合于实时的无线视频传输系统。     

TCP performance over mobile ad hoc networks

TCP is a transport protocol that guarantees reliable ordered delivery of data packets over wired networks. Although it is well tuned for wired networks, TCP performs poorly in mobile ad hoc networks (MANETs). This is because TCP's implicit assumption that any packet loss is due to congestion is invalid in mobile ad hoc networks where wireless channel errors, link contention, mobility and multipath routing may significantly corrupt or disorder packet delivery. If TCP misinterprets such losses as congestion and consequently invokes congestion control procedures, it will suffer from performance degradation and unfairness. To understand TCP behaviour and improve the TCP performance over multi-hop ad hoc networks, considerable research has been carried out. As the research in this area is still active and many problems are still wide open, an in-depth and timely survey is needed. In this paper, the challenges imposed on the standard TCP in the wireless ad hoc network environment are first identified. Then some existing solutions are discussed according to their design philosophy. Finally, some suggestions regarding future research issues are presented.