Athanassios Manikas

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—In this paper, an asynchronous, multicarrier direct-sequence code-division multiple-access (DS-CDMA) array receiver is proposed based upon blind, composite channel vector estimation. Due to the fact that the combined effect of all received paths is estimated , the total number of paths can be greater than the number of antennas in the receiver array.(More)
The conventional Wiener–Hopf beamformer is subject to substantial performance degradation in the presence of steering vector pointing errors. By removing the effects of the desired signal, the modified Wiener–Hopf beamformer avoids this problem but allows cochannel interferences to pass through in order to maximise the signal-to-noise ratio. In this study,(More)
—In this paper, the manifold of a general two-or three-dimensional (2-D or 3-D) array of sensors is studied using differential geometry. By considering the azimuth and elevation angles as the parameters of interest, a manifold surface is formed embedded in a multidimensional complex space. Initially, this surface is investigated by establishing a number of(More)
— In this paper, the problem of ambiguities inherent in the manifold of any linear array structure is investigated. Ambiguities, which can be classified into trivial and nontrivial, depending on the ease of their identification, arise when an array cannot distinguish between two different sets of directional sources. Initially, the new concept of an(More)
—In this paper, the use of a crossed-dipole array is proposed in joint space-time channel estimation for asyn-chronous multipath direct sequence code division multiple access (DS-CDMA) systems. The polarization diversity offered by such an array, unlike linearly polarized arrays, is able to detect and estimate any arbitrary completely polarized signal path.(More)
—This paper is concerned with the design of super-resolution direction finding (DF) arrays that satisfy prespecified performance levels, such as detection-resolution thresholds and Cramér–Rao bounds on error variance. The sensor placement problem is formulated in the framework of subspace-based DF techniques and a novel polynomial rooting approach to the(More)