Advanced Signal Processing for Ultra-Wide-Band (UWB) Communications in Wireless Networks

无线网络中超宽带 (UWB) 通信的高级信号处理

• 批准号: 0401188
• 负责人: Ali Sayed
• 金额: $ 21万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0401188&HistoricalAwards=false
• 关键词: Advanced; Signal; Processing; Ultra; Wide

Advanced Signal Processing for Ultra-Wide-Band (UWB) Communications in Wireless NetworksFollowing the February 2002 order by the Federal Communications Commission, ultra-wide-band (UWB) communications technology has emerged as the leading standard for very high datarate applications in wireless networks. The technology will allow the wireless connection of multipledevices at very high rates and at low power consumption. UWB will allow the transmission ofvideo, audio, and other data traffic among devices at rates that may reach 480Mbps. For example,UWB could stream real-time video content from a PC or a consumer electronics device, such asa camcorder, a DVD player or a personal video recorder, to a flat-screen HDTV display withoutthe need for wires. In order for this technology to become widely adopted it is necessary tomaintain the costs of UWB devices low. A major challenge arises from the signal distortionsthat are introduced during the analog processing as a result of manufacturing imperfections. Theeffects of such distortions will be compounded in future high-performance wireless networks dueto the higher silicon integration, lower power consumption, larger bandwidth, and higher carrierfrequency. There are at least two strategies to address this diffculty. One strategy is generallycostly and relies on building more reliable front-end radios. The second strategy, which is one ofthe objectives of this proposal, is to model and cancel signal distortions by using advanced signalprocessing and compensation algorithms in the digital domain. This research proposes a systematicway for modeling distortion effects, exploiting the distortion models in receiver design, developingenhanced OFDM receivers that counter-balance the effects of distortions and that improve therange of UWB devices, investigating theoretical limits of performance, and also implementing andtesting the developed algorithms on an FPGA testbed.Objectives. (1) Develop distortion models and distortion cancellation techniques for UWB de-vices by using advanced signal processing algorithms in the digital domain. (2) Develop enhancedOFDM receivers for UWB communications by jointly addressing the issues of improved range,improved channel estimation, and distortion compensation. (3) Use the developed distortion can-cellation receivers for both single user and multi-user (space-time coded) communications scenarios.(4) Investigate theoretical limits of performance and effects of distortion on system performance. (5)Pursue a proof-of-concept implementation of a UWB system on an FPGA by using the developedalgorithms in order to investigate the models and the algorithms for improved performance.Intellectual Merit of the Proposed Activity. The PI and his research group have extensive researchexperience on different aspects of advanced signal processing, communications, and adaptive systemdesign. The proposed research activity is creative in several respects: (1) It recognizes the need toaddress signal distortions introduced by analog processing as a step towards maintaining the costof UWB devices low. (2) It recognizes the importance of cancelling distortion in the digital domain,as opposed to the analog domain. (3) It studies the effects of major sources of distortion (includingIQ imbalances, phase noise, and transmitter and receiver nonlinearities) on algorithm developmentand performance. (4) It addresses major performance hurdles such as enhanced channel estimationin order to incorporate distortion models, the design of distortion-robust OFDM-based SISO andMIMO (space-time coded) communications, and the need for improved range for UWB devices dueto their limited transmit power. (5) It pays attention to the intricate balance between algorithmcomplexity and hardware implementation.Broader Impacts of the Proposed Activity. The broader impacts of the proposed research areas follows: (1) It has significant implications on the information technology infrastructure of thenation by making the promising UWB technology widely spread at lower costs. (2) It contributesto the development of ultra-high-speed wireless networks for PC peripherals, consumer electronics,home networking, and mobile devices at data rates that may reach 480Mbps. (3) It trains bothgraduate and undergraduate students in an area of fundamental relevance to future communicationssystems. (4) The results of the research will be widely disseminated online and via publications inarchival journals and conference proceedings, and also via demonstrations of the hardware testbed.A-1

无线网络中超宽带（UWB）通信的高级信号处理根据联邦通信委员会2002年2月的命令，超宽带（UWB）通信技术已成为无线网络中极高数据速率应用的领先标准。该技术将允许多个设备以非常高的速率和低功耗进行无线连接。UWB将允许视频、音频和其他数据流量在设备之间以可能达到480Mbps的速率传输。例如，UWB可以将实时视频内容从PC或消费电子设备（阿萨摄像机、DVD播放器或个人录像机）传输到平板HDTV显示器，而不需要电线。为了使这项技术得到广泛采用，有必要保持UWB设备的低成本.一个主要的挑战来自于模拟处理过程中由于制造缺陷而引入的信号失真。在未来高性能无线网络中，由于更高的硅集成度、更低的功耗、更大的带宽和更高的载波频率，这种失真的影响将更加严重。至少有两种策略可以解决这个难题。一种策略通常是昂贵的，并依赖于建立更可靠的前端无线电。第二个策略，这是本提案的目标之一，是通过使用先进的信号处理和补偿算法在数字域中的模型和消除信号失真。本研究提出了一种系统的方法来建模失真的影响，利用失真模型在接收机设计，开发增强的OFDM接收机，抵消失真的影响，提高超宽带设备的范围，研究性能的理论极限，并实现和测试的FPGA测试平台上开发的算法。(1)通过使用数字域中的先进信号处理算法，开发UWB设备的失真模型和失真消除技术。(2)通过共同解决改善范围、改善信道估计和失真补偿等问题，开发用于UWB通信的增强型OFDM接收机。(3)使用开发的失真抵消接收机的单用户和多用户（空时编码）通信的情况下。(4)研究性能的理论限制以及失真对系统性能的影响。（5）利用所开发的算法在FPGA上实现UWB系统的概念验证，以研究提高性能的模型和算法。PI和他的研究小组在先进信号处理、通信和自适应系统设计的不同方面都有丰富的研究经验。提出的研究活动在几个方面是创造性的：（1）它认识到需要解决信号失真所引入的模拟处理作为一个步骤，以保持UWB设备的成本低。(2)它认识到在数字域而不是模拟域中消除失真的重要性。(3)它研究了主要失真源（包括IQ不平衡、相位噪声以及发射机和接收机非线性）对算法开发和性能的影响。(4)它解决了主要的性能障碍，如增强的信道估计，以纳入失真模型，失真鲁棒的OFDM为基础的SISO和MIMO（空时编码）通信的设计，并需要改善UWB设备由于其有限的发射功率范围。(5)它关注算法复杂性和硬件实现之间的微妙平衡。拟议活动的更广泛影响。所提出的研究领域的更广泛的影响如下：（1）它对国家的信息技术基础设施具有重大意义，使有前途的UWB技术以较低的成本广泛传播。(2)它有助于为PC外设、消费电子产品、家庭网络和移动的设备开发数据速率可达480 Mbps的超高速无线网络。(3)它培养研究生和本科生在一个领域的基本相关性，以未来的通信系统。(4)研究结果将在网上广泛传播，并通过出版物、存档期刊和会议记录以及硬件试验台的演示进行传播。