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根据3GPPR5,R6版本协议的技术声明以及现在通信技术的需求,介绍了即将被商用的HSDPA(高速下行分局接入技术)的演进技术——HSOPA(高速OFDM分组接入技术)。简单介绍了HSOPA的技术特点,并介绍了HSOPA的关键技术(OFDM及MIMO技术等),以及展望了HSOPA技术向后3G及4G的过渡情况。 相似文献
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文中根据3GPP R5,R6版本协议的技术声明以及现在通信技术的需求,介绍了即将被商用的HSDPA(高速下行分组接入技术)的演进技术--HSOPA(高速OFDM分组接入技术).文中从3G技术的发展谈起,引出所要讨论的HSOPA技术,随后简单介绍了HSOPA的技术特点,并着重介绍了HSOPA的关键技术(OFDM及MIMO技术等),最后展望了HSOPA技术向后3G及4G的过渡情况,提出所讨论的HSOPA技术的可实现性. 相似文献
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本文根据3GPP R5,R6版本协议的技术声明以及现在通信技术的需求,介绍了即将被商用的HSDPA(高速下行分局接入技术)的演进技术——HSOPA(高速OFDM分组接入)的技术特点,关键技术(OFDM及MIM0技术等),展望了HSOPA技术向后3G及4G的过渡情况。 相似文献
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基于正交频分复用(OFDM)和多入多出(MIMO)的高速OFDM分组接入(HSOPA)是通用移动通信系统(UMTS)网络中高速下行分组接入(HSDPA)的下一代演进技术。通过利用OFDM和MIMO技术,HSOPA可以提高频谱效率,支持更多的用户数目和更高的QoS保证,降低每兆字节的传输成本,从而大大提高运营商的商业竞争力。 相似文献
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基于正交频分复用(OFDM,Orthogonal frequency division multiplexing)和多入多出(MIMO, Multiple Input Multiple Output)的高速OFDM分组接入(HSOPA,High-Speed OFDM Packet Access)是UMTS网络中高速下行分组接入(HSDPA,High-Speed Downlink Packet Access)的下一步演进技术。通过利用OFDM,MIMO技术,HSOPA可以提高频谱效率,支持更多的用户数目和更高的QoS保证,降低每兆字节的传输成本,从而大大的提高运营商的商业竞争力。 相似文献
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基于正交频分复用(OFDM)和多入多出(MIMO)的高速OFDM分组接入(HSOPA)是UMTS网络中高速下行分组接入(HSDPA)的下一步演进技术.通过利用OFDM及MIMO技术,HSOPA可以提高频谱效率,支持更多的用户数目和更高的QoS保证,降低每兆字节的传输成本,从而大大提高运营商的商业竞争力. 相似文献
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文章主要介绍了基于正交频分复用(OFDM)和多入多出(MIMO)的高速OFDM分组接入(HSOPA)技术。详细阐述了其优点所在,最后对HSOPA的频谱规划提出了建议。 相似文献
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介绍了3G(第3代移动通信系统)中WCDMA(宽带码分多址)系统与TD-sCDMA(时分同步码多分址)系统的HSDPA(高速下行分组接入)技术以及CDMA2000系统的1x EV-DO和1xEV-DV技术原理,展示了这些技术的最新发展状况和关键技术,分析了自适应调制技术、快速功率控制等在高速分组接入中的应用,并对这些分组接入技术进行了对比,展望了3G分组接入技术的发展方向,提出高速分组接入技术向超3G发展演进的发展趋势. 相似文献
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By means of exact conformal mapping method we have defined character of dependence of squares amounts of angular part of film
element on angled part dimension. We propose relations, approximating obtained dependence. Calculation results and experimental
researches of large-scale models are represented. 相似文献
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Moshrefzadeh R.S. Radcliffe M.D. Lee T.C. Mohapatra S.K. 《Lightwave Technology, Journal of》1992,10(4):420-425
The temperature dependence of refractive index of polymer films was determined for a number of slab waveguides by a grating coupling method. This dependence was examined as a function of parameters such as molecular weight and glass transition temperature of the polymer. Temperature-induced changes in N TE-N TM , N being the effective index, were studied systematically for different slab waveguide compositions. It is shown that with proper device design and choice of polymeric materials, thermal effects can be reduced 相似文献
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The approaches to prepare a uniform and unified scientific terminology of chemical carcinogenesis are presented. The main definitions proposed (carcinogen, initiation, promotion, mutagen, multistage carcinogenesis, anti-carcinogen, cocarcinogen, carcinogenic risk, etc.) are based on the current state of comprehending mechanisms of the action of chemical carcinogens. 相似文献
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The article describes a model representation of radar probing data in form of a mixture of background and target samples, which is the sum of two random variables with very different parameters. For model development we research the behavior of the central moments of the distribution mix without assuming the distribution law form. An example it is described the detection of the signal at the output of compression system of chirp ionosonde. 相似文献
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解决IP网QoS问题是目前通信领域的研究热点之一.虽然研究已经取得了一定的进展,但人们对于IP 网QoS本身的含义及相关的问题还有着不同的理解.本文将从IP网QoS的定义入手讨论相关的一些问题以及解决IP网QoS问题所做的各种努力. 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1968,56(6):1024-1032
Assuming that visual responses are due to the action of particles on the membrane of the visual cells, the stochastic variability of the response should be a function of the number of particles producing it. Quantitative predictions can be made with the aid of a model proposed in previous articles. It is found that responses produced in visual cells of Limulus by absorption of a single photon have the stochastic properties which would be expected if the response to one photon were brought about by 25 particles. It is concluded from this that the processes leading to visual responses produce multiplication of particles. The effects of temperature and of metabolic poisons suggest that these processes are of chemical nature. 相似文献
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《半导体学报》2008,29(12):2470-2470