Show simple item record

dc.contributor.advisorLiu, K. J. Rayen_US
dc.contributor.authorSiriwongpairat, Wipaweeen_US
dc.date.accessioned2006-02-04T07:01:23Z
dc.date.available2006-02-04T07:01:23Z
dc.date.issued2005-11-28en_US
dc.identifier.urihttp://hdl.handle.net/1903/3122
dc.description.abstractUltra-wideband (UWB) is an emerging technology that offers great promises to satisfy the growing demand for low cost and high-speed digital wireless home networks. The enormous bandwidth available, the potential for high data rates, as well as the potential for small size and low processing power long with low implementation cost, all present a unique opportunity for UWB to become a widely adopted radio solution for future wireless home-networking technology. Nevertheless, in order for UWB devices to coexist with other existing wireless technology, the transmitted power level of UWB is strictly limited by the FCC spectral mask. Such limitation poses significant design challenges to any UWB system. This thesis introduces various means to cope with these design challenges. Advanced technologies including multiple-input multiple-output (MIMO) coding, cooperative communications, and cross-layer design are employed to enhance the performance and coverage range of UWB systems. First a MIMO-coding framework for multi-antenna UWB communication systems is developed. By a technique of band hopping in combination with jointly coding across spatial, temporal, and frequency domains, the proposed scheme is able to exploit all the available spatial and frequency diversity, richly inherent in UWB channels. Then, the UWB performance in realistic UWB channel environments is characterized. The proposed performance analysis successfully captures the unique multipath-rich property and random-clustering phenomenon of UWB channels. Next, a cross-layer channel allocation scheme for UWB multiband OFDM systems is proposed. The proposed scheme optimally allocates subbands, transmitted power, and data rates among users by taking into consideration the performance requirement, the power limitation, as well as the band hopping for users with different data rates. Also, an employment of cooperative communications in UWB systems is proposed to enhance the UWB performance and coverage by exploiting the broadcasting nature of wireless channels and the cooperation among UWB devices. Furthermore, an OFDM cooperative protocol is developed and then applied to enhance the performance of UWB systems. The proposed cooperative protocol not only achieves full diversity but also efficiently utilizes the available bandwidth.en_US
dc.format.extent1937168 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.titleCross-Layer Design for Multi-Antenna Ultra-Wideband Systemsen_US
dc.typeDissertationen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.contributor.departmentElectrical Engineeringen_US
dc.subject.pqcontrolledEngineering, Electronics and Electricalen_US
dc.subject.pquncontrolledultra-widebanden_US
dc.subject.pquncontrolledmultiband OFDMen_US
dc.subject.pquncontrolledcross-layer designen_US
dc.subject.pquncontrolledMIMOen_US
dc.subject.pquncontrolledspace-time codingen_US
dc.subject.pquncontrolledcooperative communicationsen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record