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1.
TD-LTE室内覆盖是网络规划、建设的重要环节.本将TD-LTE 3种室内覆盖规划方案划分为三大类方式:分别是通过室外基站、室内分布系统和室内微基站进行室内覆盖.通过室外基站进行室内覆盖具有节省投资,建网速度较快,室内室外覆盖联合规划等优点.通过有源和无源分布系统进行室内覆盖适合于对业务数据速率和业务量要求较高,需要深度覆盖的场所,是大多数中大型场所的室内覆盖解决方案.通过室内微基站进行室内覆盖主要适合小型的办公娱乐场所,以及住宅弱信号覆盖楼层,具有传输接入简单,建网成本等优点. 相似文献
2.
高层室内覆盖解决方案浅析 总被引:1,自引:0,他引:1
通过对高层室内覆盖现状的调查,我们发现了高层室内覆盖存在的一些问题,并对高层室内覆盖的布线系统设计进行了分析,并结合典型高层室内覆盖解决案例,整理出高层室内覆盖问题的解决思路。 相似文献
3.
本文为发掘室内弱覆盖做好室内覆盖,首先介绍主要的无线传播模型,其次利用CrossWave射线传播模型,通过对室内无线网络覆盖情况的仿真,得出室内弱覆盖的分析方法,最后结合无线网络建设现状找到室内弱覆盖区域。 相似文献
4.
对比分析移动通信室内覆盖系统中传统室内覆盖系统和新型有源数字室内覆盖系统各自的特点,针对4G移动通信室内覆盖系统的局限性,并结合5G的技术特性,提出在4G向5G演进过程中室内覆盖存在的问题和将面对的挑战,阐述室内覆盖系统演进的方式和部署策略。 相似文献
5.
4G时代的室内覆盖建设效果影响运营商的网络投资效果。如何破解有信号却无法上网的窘境,每个阶段均有不同的解决方法。创新型室内覆盖建设模式的出现对室内覆盖效果的提升有积极作用。文章全面比较常规室内覆盖建设模式和创新型室内覆盖建设模式的性能特点和应用场景,指出现阶段不同室内覆盖建设模式存在的问题,为解决室内覆盖建设难题提出建议。 相似文献
6.
TD-SCDMA室内分布场景与方案设计 总被引:1,自引:0,他引:1
室内分布系统是解决室内覆盖,吸收话务量,提高用户满意度的直接有效方式.当前TD-SCDMA即将步入商用化,由于TD-SCDMA具有时分、智能天线等关键特性,室内覆盖的方式、设备注定不同于传统的室内覆盖解决方案.本文探讨了不同覆盖场景内不同覆盖解决方案,为TD-SCDMA室内覆盖的设计提供了参考. 相似文献
7.
随着移动通信的普及和3G网络的逐步商用,城市室内的深度覆盖越来越重要。室内深度覆盖一方面要建设室内覆盖系统,另一方面要对室内外无线信号进行联合优化,通过基站天线、参数调整结合室内分布系统的调整提高室内综合通信质量。电梯作为室内覆盖的一个特殊场景需要加以重点考虑。一、WCDMA室内覆盖组网概况 相似文献
8.
随着LTE网络的陆续商用,移动数据业务将比3G时代更加快速的发展,而在LTE时代大量业务将集中在少数热点价值场景,尤其是室内数据业务将更加集中,室内覆盖容量需求不断增加。为了解决LTE深度覆盖精品网建设,提供更好的室内覆盖业务,业界推出了Lamp Site室内覆盖创新解决方案。本文主要介绍Lamp Site室内覆盖解决方案,并通过对室内试点场景测试情况分析,研究Lamp Site方案建设,为今后室内覆盖场景采用Lamp Site室内覆盖创新解决方案提供依据和指导。 相似文献
9.
5G网络具备室内外同频的特性,使户外宏站的深度覆盖得到加强。同时,不同的频带、不同的覆盖模式也会影响不同的室内覆盖效果。文章从5G网络室内覆盖特性的分析出发,对当前室内覆盖网络所面临的室内外同频干扰以及传统的室内覆盖网络进行了优化,并就5G网络的室内覆盖网络的改造提出了几点建议。 相似文献
10.
首先分析了3G室内覆盖的重要性,并对3G室内覆盖的基本方法进行了介绍和比较,接着简要介绍了3G室内覆盖的规划原则;最后给出了3G室内覆盖的一个工程实践实例。 相似文献
11.
Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
12.
Thomas M.Trexler 《半导体技术》2004,29(5)
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test. 相似文献
13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
16.
Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
17.
Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
19.
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
20.
《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献