共查询到20条相似文献,搜索用时 15 毫秒
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Middya Asif Iqbal Roy Sarbani Dutta Joy Das Rituparna 《Mobile Networks and Applications》2020,25(4):1249-1274
Mobile Networks and Applications - Participatory sensing has become an effective way of sensing urban dynamics due to the widespread availability of smartphones among citizens. Traditionally,... 相似文献
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Hiram Galeana-Zapién Javier Rubio-Loyola Pablo Salazar-Linares Ramón Agüero Joan Serrat Steven Davy 《Mobile Networks and Applications》2012,17(4):479-491
The incremental efforts needed to manage low-level radio access network decisions from a business-perspective have received little attention so far. This paper considers the influence of business-level indicators on network management decisions related to low-level network control mechanisms. It provides a formal understanding of all involved aspects, the representation of the adjustable parameters, and the network control mechanisms that enable the reconfiguration of access network entities from a business perspective (i.e., users?? information, operator??s goals). The effectiveness of our approach is validated through a simulation environment that we developed on OPNET. 相似文献
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Liao Shih-Wei Kuang Shao-Yun Kao Chia-Lung Tu Chia-Heng 《Journal of Signal Processing Systems》2019,91(3-4):219-233
Journal of Signal Processing Systems - New programming models have been developed to embrace contemporary heterogeneous machines, each of which may contain several types of processors, e.g., CPUs,... 相似文献
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Spectrum sensing feature of cognitive radio devices represents a cornerstone characteristic facilitating real-time and accurate
spectrum occupancy measurements in cognitive radio networks. It practically enables the cognitive radio devices to detect
vacant spectrum holes and use them for their communication purposes. There are numerous spectrum sensing methods proposed
in the literature ranging from local based ones to cooperative strategies among several devices increasing the confidence
level of the detected spectrum. This paper gives a general spectrum sensing framework for cognitive radio networks, classifies
and explores different spectrum sensing techniques and approaches and shows practical examples, from authors’ own experience,
of realized spectrum sensing engines and strategies along with some obtained results. 相似文献
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文中提出了一种基于信任的合作频谱感知框架.通过本地感知差异、感知位置因素、控制信道条件为参与频谱感知的用户建立信任,准确地权重决策中心的单用户感知信息.仿真结果表明,在一定虚警概率的约束条件下,该框架应用于具体模型时具有较低的漏检概率. 相似文献
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Alfonso Cesar B. Albason Danny Wen-Yaw Chung Shyh-Liang Lou 《Journal of Signal Processing Systems》2011,62(3):263-272
An implementation of an implantable sensing biosystem composes of a readout circuit, a power management block, an embedded
microcontroller unit (MCU), an implantable drug delivery section and a wireless uplink transceiver system. This paper describes
a bi-directional wireless transceiver system for implantable sensing systems. The transceiver system is composed of an external
and implantable transceiver, communicating through an inductive link. Half duplex communication between transceivers at a
10 Kbps data rate was achieved at a maximum distance of 4 cm. Command and data will be supplied to the implantable module
by radio frequency (RF) telemetry utilizing an amplitude shift keying (ASK) modulated 2 MHz carrier frequency. A capacitor-less
amplitude demodulation receiver architecture was produced in the research with implantable receiver core area measuring at
113.2 μm by 171.8 μm with average power dissipation at 815.1 μW at a 3.3 V single rail power supply. An active uplink transceiver
utilizing load shift keying (LSK) as backward data telemetry was designed. Implantable transmitter core area measures 251.7 μm
by 139.3 μm, consuming 103.62 mW while driving an RF ferrite core antenna at maximum reading range. Integrating both circuits,
implantable transceiver, measuring 355.3 μm by 171.8 μm, was designed and implemented using TSMC 0.35 μm mixed-signal 2P4M
3.3 V standard CMOS process. The integrated circuit solution addressed solutions for many of the problems associated with
implanted devices and introduces circuits which improve in several ways over previously published designs, in functionality
and integration level. In addition to being fully integrated in plain CMOS technology, not relying at least partly on available
specialized elements and expensive technologies, these building blocks improve on previous designs in performance and/or power
consumption. This work succeeded in implementing building blocks for an implantable transceiver, which depends only on the
absolute minimum off-chip components. A complete implantable chip is presented, which highlight the design tradeoffs and optimizations
applied to the design of CMOS implantable system chips. 相似文献
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Alessandro Mortara 《Analog Integrated Circuits and Signal Processing》1997,13(1-2):93-101
This paper presents the principles, the main propertiesand some applications of a pulsed communication system adaptedto the needs of the analog VLSI implementation of perceptivesystems. The system takes advantage of the fact that activitiesin perception tasks are often sparsely distributed over a largenumber of elementary processing units (cells) and facilitatesaccess to the communication channel for the more active cells.The resulting architecture can be advantageously used to setup connections between distant cells on the same chip or point-to-pointconnections between cells on different chips when direct wiringis prohibitive. Cells communicate in an asynchronous fashionwhich conserves the fine time relationships of events. The systemalso lends itself to the simple circuit implementation of typicalbiologically inspired connectivity patterns such as projectionof the activity of one cell on a region (its projective field)of the next neural processing layer, which can be on a differentchip in an actual implementation, as is the case for one of theapplications presented: an oriented-edges enhancement system. 相似文献
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In this letter, we analyze the problems with the existing telematics service systems that have been dependently developed and provided on a specific mobile network infrastructure. Then, we suggest methods to solve the problems and propose an architecture of the gateway and framework to implement our methods. We also verify the effectiveness of the suggested architecture through a comparison with an existing telematics system. With this architecture, it is possible to develop service applications without knowledge of the underlying mobile network technology and the system integration methods. 相似文献
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In earlier works on transmitter power control in cellular radio systems, the problem of whether a signal‐to‐interference ratio (SIR) threshold is achievable is determined by apparently different rules for homogeneous and heterogeneous SIR systems. In this paper, we present a unified and more universal framework for both cases. We also highlight the conditions under which a given SIR threshold vector for the heterogeneous SIR system is achievable, although so far there is no general solution to this problem. 相似文献
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自适应滤波框架中,滤波器的抽头系数可以利用特定的自适应算法达到近似维纳解,从而使滤波器的输出误差达到最小.将这个框架应用到压缩感知重构信号中,信号的稀疏系数等效为滤波器系数权值向量,从而可获得最佳的稀疏系数,以高概率重构信号.本文介绍了已有学者研究出的一种L0最小均方算法(L0-LMS),该算法中引入零引力项加快了权矢量向稀疏解收敛的速度,保证解的稀疏性.通过仿真可知,基于自适应滤波算法重构稀疏信号的性能较好,甚至优于压缩感知中常用的OMP算法. 相似文献
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Lunden J. Koivunen V. Huttunen A. Poor H.V. 《Signal Processing, IEEE Transactions on》2009,57(11):4182-4195
This paper proposes an energy efficient collaborative cyclostationary spectrum sensing approach for cognitive radio systems. An existing statistical hypothesis test for the presence of cyclostationarity is extended to multiple cyclic frequencies and its asymptotic distributions are established. Collaborative test statistics are proposed for the fusion of local test statistics of the secondary users, and a censoring technique in which only informative test statistics are transmitted to the fusion center (FC) during the collaborative detection is further proposed for improving energy efficiency in mobile applications. Moreover, a technique for numerical approximation of the asymptotic distribution of the censored FC test statistic is proposed. The proposed tests are nonparametric in the sense that no assumptions on data or noise distributions are required. In addition, the tests allow dichotomizing between the desired signal and interference. Simulation experiments are provided that show the benefits of the proposed cyclostationary approach compared to energy detection, the importance of collaboration among spatially displaced secondary users for overcoming shadowing and fading effects, as well as the reliable performance of the proposed algorithms even in very low signal-to-noise ratio (SNR) regimes and under strict communication rate constraints for collaboration overhead. 相似文献
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Pagello E. D'Angelo A. Menegatti E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2006,94(7):1370-1383
This paper considers the properties a multirobot system should exhibit to perform an assigned task cooperatively. Our experiments regard specifically the domain of RoboCup middle-size league (MSL) competitions. But the illustrated techniques can be usefully applied also to other service robotics fields like, for example, videosurveillance. Two issues are addressed in the paper. The former refers to the problem of dynamic role assignment in a team of robots. The latter concerns the problem of sharing the sensory information to cooperatively track moving objects. Both these problems have been extensively investigated over the past years by the MSL robot teams. In our paper, each individual robot has been designed to become reactively aware of the environment configuration. In addition, a dynamic role assignment policy among teammates is activated, based on the knowledge about the best behavior that the team is able to acquire through the shared sensorial information. We present the successful performance of the Artisti Veneti robot team at the MSL Challenge competitions of RoboCup-2003 to show the effectiveness of our proposed hybrid architecture, as well as some tests run in laboratory to validate the omnidirectional distributed vision system which allows us to share the information gathered by the omnidirectional cameras of our robots. 相似文献
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随着当前移动终端设备的发展和5G技术的普及,移动群智感知的需求越来越大.但是目前感知任务的分发方法依然存在着传输效率低下、代价高且不稳定等问题,极大地限制了感知终端任务的完成.为此,该文利用城市轨道交通对于各大城区良好的覆盖性和轨道交通的可预测性,提出了面向激励成本的任务分发模型(ICTDM)和面向用户数量的任务分发模型(UNTDM).通过轨道交通对聚集式人流的疏导性,实现感知任务在城市不同区域的选择性分发.并以任务所需人数和移动距离的最小化作为手段,完成降低系统总激励成本的目的.实验结果表明,该算法与同类算法相比,可以在完成相同任务集合的前提下,通过优化任务分发过程实现更少的任务参与者分发方案,以达到降低感知任务成本的目的. 相似文献
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Ming Jin Youming Li Zhenghao Zhang Rangding Wang 《Wireless Personal Communications》2012,66(2):419-428
Cognitive radio is a promising technology for alleviating the spectrum shortage problem which is caused by current fixed spectrum allocation policy. With a smart antenna configured in a secondary user, this paper proposes a new spectrum sensing algorithm exploiting the correlation of channel gains between antenna elements. The proposed method detects the primary user signal with the test-statistics based on antenna correlation. Compared to available antenna correlation based spectrum sensing algorithm, the proposed algorithm can determine easily the decision threshold level for achieving required false alarm probability under given number of samples, and achieves a better performance. Finally, the proposed algorithm is verified by numerical simulation. 相似文献
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L. Benini D. Bruni M. Chinosi C. Silvano V. Zaccaria R. Zafalon 《Design Automation for Embedded Systems》2002,7(3):183-203
This paper describes a technique for modeling and estimating the power consumptionat the system-level for embedded VLIW (Very Long Instruction Word) architectures.The method is based on a hierarchy of dynamic power estimationengines: from the instruction-level down to the gate/transistor-level. Powermacro-models have been developed for the main components of the system: theVLIW core, the register file, the instruction and data caches. The main goalis to define a system-level simulation framework for the dynamic profilingof the power behavior during the software execution, providing also a break-downof the power contributions due to the single components of the system. Theproposed approach has been applied to the Lx family of scalable embedded VLIWprocessors, jointly designed by STMicroelectronics and HPLabs. Experimentalresults, carried out over a set of benchmarks for embedded multimedia applications,have demonstrated an average accuracy of 5% of the instruction-level estimationengine with respect to the RTL engine, with an average speed-up of four ordersof magnitude. 相似文献
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Liang Guanzhong Sun Chuan Zhou Jianing Luo Fengji Wen Junhao Li Xiuhua 《Mobile Networks and Applications》2022,27(4):1629-1641
Mobile Networks and Applications - Due to the growing number of users and items in recommender system, along with the more complex algorithms for precise recommendation, recommender system in... 相似文献
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设计实现了一个可复用的面向并行DSP应用的消息传递软件框架.为了实现DSP软件的编码能够独立于不同的并行处理器体系结构, 设计分层的软件框架结构和各层中类间的关系.为了DSP应用的开发能够独立于底层的数据通信路径,提高并行系统的可扩展与可配置性,设计基于处理器间数据流模型和硬件平台拓扑模型的节点路由表结构和路由算法. 以TigerSHARC DSP构成的并行DSP系统为例,说明软件框架应用于特定的多处理器平台的方法,实现并验证了消息传递软件框架. 相似文献