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It is well known that multiple-input multiple-output (MIMO) techniques can bring numerous benefits, such as higher spectral efficiency, to point-to-point wireless links. More recently, there has been interest in extending MIMO concepts tomultiuser wireless systems. Our focus in this paper is on network MIMO, a family of techniques whereby each end user in a wireless access network is served through several access points within its range of influence. By tightly coordinating the transmission and reception of signals at multiple access points, network MIMO can transcend the limits on spectral efficiency imposed by cochannel interference. Taking prior information-theoretic analyses of networkMIMO to the next level, we quantify the spectral efficiency gains obtainable under realistic propagation and operational conditions in a typical indoor deployment. Our study relies on detailed simulations and, for specificity, is conducted largely within the physical-layer framework of the IEEE 802.16e Mobile WiMAX system. Furthermore,/nto facilitate the coordination between access points, we assume that a high-capacity local area network, such as Gigabit Ethernet,/nconnects all the access points. Our results confirm that network MIMO stands to provide a multiple-fold increase in spectral/nefficiency under these conditions.

A new linear feature detector for synthetic aperture radar (SAR) images is presented in this article by embedding a three-region filter into the wedgelet analysis framework. One of its main features is that it can detect linear features with a range of varying widths and orientations in the same image by changing the direction and size of the detector mask within a multiscale framework. In addition, this detector takes into account both statistical and geometrical characteristics to detect line segments directly instead of detecting target pixels. To show its effectiveness, the detector is applied to extract one of the most important linear features: roads. Results and comparisons with several multiscale analysis techniques as well as ratio correlation detector on DLR E-SAR images reveal its advantages.

Reproducible research results become more and more an important issue as systems under investigation are growing permanently in complexity, and it becomes thus almost impossible to judge the accuracy of research results merely on the bare paper presentation.