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71.
Transparent Electronics: Thermally Stable Transparent Resistive Random Access Memory based on All‐Oxide Heterostructures (Adv. Funct. Mater. 15/2014)
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72.
73.
The area covered by a mobile ad hoc network consists of obstacles that inhibit transmission and areas where communications
can take place. Physical structures, such as buildings, that block transmission, or lakes, where forwarding nodes cannot be
located, are permanent obstacles. Temporary obstacles are created as mobile nodes enter or leave an area. Our hypothesis is
that the spaces between nearby obstacles are bottlenecks that inhibit the flows in the network. We partition the network into
areas that are encompassed by obstacles and bottlenecks. All of the nodes in an area are treated as a single super node, and
the bottlenecks between areas are the links between the super nodes. As individual nodes move, the flows and paths in the
model change more slowly than the paths and flows between the individual nodes. We apply flow control algorithms to the model
and perform admission control within a super node based on the flows that are assigned by the flow control algorithm. We apply
the model to the Columbia University campus, and use max–min, fair bottleneck flow control to assign the flows. Our hypothesis
is verified for this example. 相似文献
74.
75.
Ling Ding James S. Lehnert 《International Journal of Wireless Information Networks》2000,7(3):115-132
In this paper, we propose and analyze a simple adaptive uplink power control scheme, called two-level channel inversion, for data traffic in a cellular CDMA system. The basic idea is to reduce out-cell interference by reducing the rate of, or even suspending, transmission when the wireless channel is in a bad condition. We first describe the scheme in detail, and then present a probabilistic analysis model for evaluating the system performance. With this model, we determine the queueing delay and system throughput. Numerical results show that in comparison with the traditional channel inversion scheme, the two-level channel inversion scheme can substantially improve system throughput at a moderate cost of extra queueing delay. Finally, we present a design algorithm to optimize the overall performance while maintaining each user's quality of service (QoS). 相似文献
76.
本文对LD数字光纤发射模块的控制方法进行了研究,从理论上对传统的自动控制法,简化的平均功率控制加温度补偿和数据0补偿法以及本文提出的直耦峰值检波控制法进行了分析并实验证明了其稳定性。 相似文献
77.
《Digital Communications & Networks》2016,2(4):256-259
This article describes the design and simulation of a pair of antennas on a small PCB with minimal coupling for a massive multiple input sensor network. The two antennas are planar inverted-F antennas (PIFA) that are fed with microstrip feed lines. The critical design factors are minimizing mass while creating ISM band and GPS L1 band antennas and developing data transmission schemes for maximum usage of all communication channels. The designed board is a 60 mm diameter, 0.6 mm thick circular FR4 board that weighs approximately 5 g. 相似文献
78.
在LTE(长期演进)上行随机接入中,接收端对前导的检测是一个很重要的步骤。由于前导序列较长,传统的接收端算法运算量较大。为了减小接收端算法的运算量,引入降采样,对传统的接收端算法进行改进。改进后的接收端算法运算量大大减少。以格式0为例,在一个计算周期内,改进后的算法运算量是改进前运算量的1/120。MTLAB仿真结果表明,改进前后的接收端算法在检测性能上差别较小。在不同的信道环境下,经过改进后的算法仍然具有较好的检测性能。 相似文献
79.
介绍了宽带接入技术的发展和IPoE系统的结构;将IPoE和PPPoE系统进行对比,对BNG设备的设计进行了探讨;对上海贝尔端到端BNG网络解决方案进行了阐述。 相似文献
80.
This article advocates a novel communication architecture and associated collaborative framework for future wireless communication
systems. In contrast to the dominating cellular architecture and the upcoming peer-to-peer architecture, the new approach
envisions a cellular controlled short-range communication network among cooperating mobile and wireless devices. The role
of the mobile device will change, from being an agnostic entity in respect to the surrounding world to a cognitive device.
This cognitive device is capable of being aware of the neighboring devices as well as on the possibility to establish cooperation
with them. The novel architecture together with several possible cooperative strategies will bring clear benefits for the
network and service providers, mobile device manufacturers and also end users.
相似文献
Qi ZhangEmail: |