适用于2．5／3G移动通信网关设备的DSP

Agere Systems公司前身系朗讯科技的微电子部门,主要提供通信系统中的核心部件,产品涵盖了从光传输、网络通信、接入、无线和终端几乎所有领域。自从贝尔实验室发明DSP以来,Agere Systems一直向业界提供高性能的DSP产品。     

基于TI DSP的OMAP架构推动2．5G和3G的无线应用

采用双核结构的OMAP应用处理器能够使无线手机和移动因特网设备提供先进的多媒体服务,支持Windows Media音频、视频和数字版权管理(DRM)技术     

面向移动通信的DSP发展动向

DSP在移动通信终端产品中是实时处理声音编码/解码、声音识别和活动图像的关键器件。世界各大半导体制　造商,对于DSP的研究与开发都给予高度重视,各自都为　多争取一些市场份额而努力奋斗,不断开发出新一代面向　移动通信的DSP产品。 　 随着Internet应用的深入普及,以第3代移动通信手　段来无线接入Internet正蔚然成风,方兴未艾。例如,现　在利用IMT-2000手机,可以享受高速且大容量的数据通　信服务,诸如听音乐 欣赏静止图像和活动图像。因此,对　数字信号处理器提出严格要求,如像要求更高速的处理能　力而且实现低功耗化。于是,各个DSP制造商纷纷推出各　自的新一代DSP产品。本文以NEC的μPD7721x系列新     

移动通信中的π／4QPSK调制解调技术及DSP实现

介绍了一种比ＧＭＳＫ具有更优的频谱特性，频谱利用率及更强抗衰落性能的线性窄带调制解调技术（π／４ＱＰＳＫ），并给出了它的ＤＳＰ实现和相应的性能。     

高性能DSP在VoP媒体网关中的应用

引言 相比传统的电路变换技术,VoP技术有着独特的优势。随着VoP技术的发展,低功耗、高性能DSP的出现,传输技术的不断提高和各种协议的趋于统一,近年来,基于包交换的分组语音技术发展迅猛,己逐步成为下一代网络的关键技术之一。在向下一代网络的演进过程中,作为电路交换网和数据包交换网桥梁的VoP媒体网关扮演着重要角色。     

面向企业网关应用的多核DSP

基于KeyStone的TMS320C665x多核数字信号处理器（DSP）,可实现优异的系统级低功耗与低成本,是会话边界控制器与IPPBX网关等企业网关应用的理想选择。     

StarCore DSP结构--一种可扩展的手持设备设计方案

充分利用各种DSP应用上现有的软件对加速产品上市至为重要。这一点在支持最新标准的产品上体现得尤为明显。例如第三代移动通信对各种形式无线手持设备的需要在迅速增长,其中包括以声音、数据及媒体为主的平台等。     

蜂窝移动通信技术装备从2G到3G不会平稳过渡

峰窝移动通信经历了80年代的第一代模拟移动通信技术,90年代的第二代(2G)数字移动通信技术,2G主要为GSM和窄带CDMA技术。进入新世纪,以支持移动多媒体业务为特征的更大容量的第三代(3G)移动通信正在开发、试验,也必将投入商用。但是应当指出,2G和3G蜂窝提供的业务是大不相同的,同时就3G的技术理论基础和技术装备而言,不管是对制造商、运营商或用户设备的应用来说都是个革命性的变化。     

采用DSP的USB2．0通信接口设计

文章介绍了用于雷达信号采集处理系统中,采用DSP控制USB控制器的设计。选用数字信号处理器芯片ADSP-2188N和控制器芯片ISP1581 USB2.0实现的USB接口系统。文中给出了一种使用多芯片开发符合USB2.0规范的外设端通用数据传输模块的方法。介绍了该接口系统的硬件、固件以及驱动的设计。     

Enabling multimedia applications in 2.5G and 3G wireless terminals through a combined RISC/DSP architecture: OMAP

This paper describes how multimedia applications will be enabled in 2.5 and 3G wireless terminals thanks to the efficiency of the DSP core embedded in the TI OMAP platform. OMAP H/W architecture will be described with an emphasis on how multimedia applications (video, audio, speech) will benefit from this advanced architecture. The advantages provided by a combined RISC/DSP architecture, compared to a single RISC architecture, for multimedia mobile applications will be depicted.     

一种3G环境中基于无线网关的内网接入技术方案

随着政府信息化建设工程的快速发展和通信运营商3G网络的建设加速,手持终端设备作为信息接入点安全接入内网信息系统的需求越来越多,尤其是在电子政务、企业应用等应用方面。该文主要介绍了一种在3G无线网络环境下利用无线网络安全接入网关中转,实现移动终端和应用服务器的异构公钥证书的认证、安全数据传输的技术方案。     

新推出的DSP更加适合应用于3G 电信基础设施的设备

新型TigerSHARC ADSP-TS101S重新考虑3G移动通信基站基带处理系统,巧妙解决成本、效率、灵活性和互通性问题     

Efficient resource allocation for China's 3G/4G wireless networks

The all-IP DiffServ model is expected to be the most promising architecture for QoS provisioning in China's next-generation wireless networks, due to its scalability, convenience for mobility support, and capability of interworking heterogeneous radio access networks. This article focuses on efficient resource allocation in a wireless DiffServ architecture. Resource utilization efficiency is particularly important for China's wireless networks as the mobile user density in China is and will continue to be much higher than that in other countries. More specifically, we propose a novel buffer sharing scheme to provide assured service for real-time layer-coded multimedia traffic, which can guarantee the specific packet loss requirement of each layer with UDP as the transport layer protocol. An adaptive optimal buffer configuration can be applied to achieve maximum resource utilization over the time-varying channel. Assured service is also provided to TCP data traffic for guaranteed throughput, where the cross-layer coupling between the TCP layer and link layer is exploited to efficiently utilize the wireless resources.     

WLAN与2.5/3代移动通信网的结合

文章探讨了无线局域网与蜂窝移动数据网互连与结合的机制,介绍了无线局域网与GPRS、cdma2000 1x、WCDMA等几种网络实现互连与结合的解决方案。     

Auction-Based Resource Reservation in 2.5/3G Networks

We consider UMTS networks in which users request services other than telephony that last for long time intervals: e.g., video clips that last for several minutes. The duration of network time-slots over which resource units are allocated is much shorter. This complicates consistent reservation of resources over longer time scales, where consistent reservation is required to ensure that service quality is constant throughout the entire service session. In this paper, we define an auction-based mechanism for nearly consistent reservation of the resources of a UMTS (or GPRS) network by the users that value them the most, in order to satisfy the longer time scale requirements of their service sessions. Each of these sessions has a fixed target bit-rate. The mechanism is based on a series of Generalized Vickrey Auctions and a set of predefined user utility functions that we propose. Bidding is performed automatically on behalf of the users on the basis of each user's selection of one of these utility functions and his declaration of a total willingness to pay. We argue that under our mechanism the user does not have a clear incentive of not performing a truthful selection of a bidding function according to his own utility. The utility functions we define express appropriately the preferences of the users with respect to the resource allocation pattern in the cases where perfectly consistent allocation cannot be attained. We also provide a mapping of these functions to the UMTS service classes. The effectiveness of our resource reservation mechanism is demonstrated by means of experiments. It appears that most of the users either are served very satisfactorily or essentially are not served at all. The mechanism is implemented at the network base station, and is applicable in practical cases of networks with large numbers of users whose sessions last for many slots.     

3G移动通信中的射频元器件

以高速传输数据并能传送图像为特征的第三代(3G)移动通信系统对通信设备提出了新的要求,同时也将毫无疑问地引发新一代移动终端的革命。WCDMA、CDMA2000和TD-SCDMA作为3G通信标准已获得国际电联(ITU)的认可,它们将兼容第二代移动通信系统并在其基础上投入运营。因此,相应的3G移动通信终端必将要求满足多模式和多频段工作的需要。多模、多频段手机研发取决于先进的元器件,而前端射频元器件一直是研发的“瓶颈”所在。本文简要分析和概括3G移动通信中相关射频元器件的现状和研发进展,同时也报道一些最近的研究成果。3G移动通信系统…     

改善2.5G和3G手机发送效率的新型方案

本文介绍如何应用最新技术和降压型Dc-Dc开关调节器MAX1820来解决2.5G和3G手机发送效率的关键问题.