The ubiquitous trend to “go wireless” is a symbol of our need for independence and flexibility. To allow for such an “all-wireless” world, large amounts of information with widely varying content have to be exchanged, utilising a limited wireless spectrum. Wireless capacity is thus the keyword and research concentrates on an efficient utilisation of the available frequency spectrum. Recently, i...

We generally categorize the approaches for ultrawideband antenna array design, and consequently propose simplified concepts for antenna arrays for a high-precision, ultra-wideband FMCW radar 2-D local positioning system to obtain robustness against multi path interference, perform angle of arrival analysis, as well as instantaneous heading estimation. We focus on low-cost and mechanical robust,...

PERFORMANCE IMPROVEMENTS IN WIRELESS CDMA COMMUNICATIONS UTILIZING ADAPTIVE ANTENNA ARRAYS by Weichen Ye This dissertation studies applications of adaptive antenna arrays and spacetime adaptive processing (STAP) in wireless code-division multiple-access (('D11 A) communications. The work addresses three aspects of the CDMA communications problems: (I) near-far resistance, (2) reverse link, (3) ...

OF THE DISSERTATION Cross-Layer Design for Wireless Networks Using Antenna Arrays by Ece Gelal Doctor of Philosophy, Graduate Program in Computer Science University of California, Riverside, August 2009 Professor Srikanth V. Krishnamurthy, Chairperson One of the major problems experienced by wireless multi-hop networks is the intermittent network connectivity, which is a consequence of fluctuat...

■ The challenge of precision source location with a radio-frequency antenna array has existed from the beginnings of radiometry and has continued in modern applications with planar antenna arrays. Early work in this field was limited to estimating single source directions in one dimension with systems like crossed-loop radiometers. Currently, more advanced systems attempt to estimate azimuth an...

The smart antenna systems combine antenna arrays with digital signal processing (DSP) algorithms. In a smart antenna system a specialized signal processor computes the direction of arrival (DOA) of a user and also adds the strength of the signals from each antenna element together to form a beam towards the direction as computed by DOA. If additional users join in

This paper considers a deterministic physical model of massive multiple-input multiple-output (MIMO) systems with uniform linear antenna arrays. It is known that the maximum spatial degrees of freedom is achieved by spacing antenna elements at half the carrier wavelength. The purpose of this paper is to investigate the impacts of spacing antennas more densely than the critical separation. The a...