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HSPA+作为3GPPHSPA(包括HSDPA和HSUPA)的增强技术,为HSPA运营商提供低复杂度、低成本的4LHSPA向LTE(长期演进)平滑演进的途径,同时保持对R6版本的后向兼容性。本文对HSPA+的关键技术进行了综述和研究分析。 相似文献
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MIMO技术是未来LTE网络的重要的关键技术之一.本文介绍了MIMO的发展及技术原理,研究和分析了MIMO技术在LTE中的应用. 相似文献
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《中国新通信》2006,(23):86-86
北电完成了业界首例采用上行链路协同MIMO技术进行的无线传输,向运营商展示了当前无线技术所允许实现的网络能力,使一个蜂窝站点上能够支持的移动宽带用户数量增加一倍。对于4G无线运营商而言,采用上行链路协同MIMO技术,能够使他们在相同资本投入的情况下提高业务收入。协同MIMO技术由北电开发,是WiMAX行业标准的组成部分,也是专为3GPP WCDMA长期演进(LTE)和3GPP2 cdma EV—DO版本C标准而设计的。北电在渥太华高级无线实验室进行的演示采用了多输入多输出(MIMO)的无线天线技术,此项技术将奠定了北电4G移动宽带解决方案的基础。 相似文献
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下行增强MIMO是LTE-Advanced的关键技术之一,文章讨论了LTER8和R9的多用户MIMO的传输模式,并且就LTE-Advanced中的多用户MIMO的主要问题进行了讨论。比较了各种可能的导频设计,下行控制信令、反馈及增强的码本设计方法,探讨了多用户MIMO适用的场景以及每个用户支持多于两个layer的可能性,并介绍了标准化进展情况。 相似文献
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赵绍刚 《无线电技术与信息》2006,(10):28-31
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3GPP在R5中引入了HSDPA技术,与R99相比,它可以为用户提供更高的下行数据数率(R99中最高的速率为2Mb/s,而在R5中HSDPA的理论速率是14.4Mb/s),从而可以为用户提供更加丰富多彩的业务。在HSDPA中它采用了一些新的技术,比如自适应调制编码(AMC,Adaptive Modulation Coding)、较短的帧长、多码子操作、快速物理层HARQ(Hybrid-Automatic Repeat Request)和NodeB快速分组调度等技术。 相似文献
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介绍世界两大移动通信标准组织3GPP和3GPP2研究3G技术演进工作的情况,着重说明3G演进的需求和关键技术. 相似文献
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MIMO CDMA antenna system for SINR enhancement 总被引:1,自引:0,他引:1
Ruly Lai-U Choi Murch R.D. Letaief K.B. 《Wireless Communications, IEEE Transactions on》2003,2(2):240-249
We present a system to enhance signal-to-interference plus noise ratio (SINR) for multiple-input-multiple-output (MIMO) direct-sequence code-division multiple-access (DS/CDMA) communications in the downlink for frequency-selective fading environments. The proposed system utilizes a transmit antenna array at the base station and a receive antenna array at the mobile station with finite-impulse response filters at both the transmitter and receiver. We arrive at our system by attempting to find the optimal solution to a general MIMO antenna system. A single user joint optimum scenario and a multiuser SINR enhancement scenario are derived. In addition, a simplified one-finger receiver structure is introduced. Numerical results reveal that significant system performance and capacity improvement over conventional approaches are possible. We also investigate the sensitivity of the proposed system to channel estimation errors. 相似文献
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LTE-A是LTE技术的平滑演进,引入了多载波聚合、中继、协作多点传输等关键技术。其中,多载波聚合是在频域上进行扩展,以满足LTE-A对高带宽的需求;中继技术能带来更广的覆盖范围和更高的系统容量,同时也面临干扰复杂化问题;协作多点传输技术能提高小区边缘的吞吐量;多天线技术通过增加上下行天线端口的数量,来提高峰值速率和频谱效率。 相似文献
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5G规模商用和5G+垂直行业应用逐步发展,将推动5G传送网络相关技术、标准及产业化的发展.介绍了5G前传、中回传、光模块相关技术现状与标准化进展,并对5G传送技术及未来发展进行了展望. 相似文献
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This paper describes a new approach to the problem of enhancing the performance of a multiuser multiple-input-multiple-output (MIMO) system for communication from one base station to many mobile stations in both frequency-flat and frequency-selective fading channels. This problem arises in space-division multiplexing systems with multiple users where many independent signal streams can be transmitted in the same frequency and time slot through the exploitation of multiple antennas at both the base and mobile stations. Our new approach is based on maximizing a lower bound for the product of signal-to-interference plus noise ratio (SINR) of a multiuser MIMO system. This provides a closed-form (noniterative) solution for the antenna weights for all the users, under the constraint of fixed transmit power. Our solution is shown by simulation to have better performance than previously proposed iterative or noniterative solutions. In addition, our solution requires significantly reduced complexity over a gradient search-based method that directly optimizes the product SINRs while still maintaining similar performance. Our solution assumes channel state information is present at the base station or transmitter. 相似文献
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Evolution and standardization of the smart antenna system for software defined radio 总被引:1,自引:0,他引:1
《Communications Magazine, IEEE》2008,46(9):68-74
Transitioning proprietary or legacy software defined radio networks to open architectures, while often complicated, is increasingly critical to improve the interoperability and compatibility among SDR networks and the subsystems within those networks as well. With this in mind, two consortia, the SDR Forum and the Object Management Group, have teamed to define an open Smart Antenna specification. This specification defines a model (including an API) that simplifies the integration of an SA subsystem into a traditional SDR network. The specification is called the "Platform Independent Model (PIM) and Platform Specific Model (PSM) for the Smart Antenna" or "SA API specification." This article introduces the SA API, which provides a standard model and standard service of the SA system operating in SDR networks. 相似文献
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