In the present paper we have analysed experimentally (wind tunnel) and numerically (CFD) the impact of some morphological parameters on the flow within and above the urban canopy. In particular, this study is a first attempt in systematically studying the flow in and above urban canopies using simplified, yet more realistic than a simple array of cuboids, building arrays. Current mathematical m...

The use of short-range wireless for object positioning has seen a growing interest in recent years. This interest is compounded by the inherent GPS limitations especially in indoor situations and in urban canyons. In order to achieve the highest performance of short-range positioning systems it is important to optimize the placement of Base-Stations (BSs) in a given area. The problems of BSs pl...

In this paper the Topography Section of the University of Cagliari (Italy) presents the results of the research carried out on the Location Based Services. These are services which use the knowledge of a mobile device’s position (e. g. a mobile phone or PDA) in order to send to the user information and news.The research had the purpose of investigating some critical issues linked to the Locatio...

In the field of remote sensing, the unmixing of hyperspectral images is usually based on the use of a mixing model. Most existing spectral unmixing methods, used in the reflective range [0.4-2.5 μm], rely on a linear model of endmember reflectances. Nevertheless, such a model supposes the pixels at ground level to be uniformly irradiated and the scene to be flat. When considering a 3D landscape...

Determining orientation with respect to a known reference plays an important role in almost all modes of navigation. As the sensors required for measuring magnetic field have found their way into portable navigation devices, researchers have started investigating their application to orientation estimation in different environments. Nevertheless, the success of these sensors for orientation est...

Global Navigation Satellite Systems (GNSS) positioning accuracy indoor and urban canyons environments are greatly affected by multipath due to distortions in its autocorrelation function. In this paper, a cross-correlation function between the received sine phased Binary Offset Carrier (sine-BOC) modulation signal and the local signal is studied firstly, and a new multipath mitigation method ba...

At high frequencies, the sound propagation can be approximated by the propagation of sound particles which are reflected and absorbed at the boundaries. This propagation follows then a transport process. In urban canyons, this transport process can be reduced to a diffusion process. The resultant model allows one to obtain the spatial distribution of the acoustical energy in a street for a very...

Geometrical models are mostly used for the study and analysis of the characteristics of radio communication channels. In this paper, a three-dimensional semi-ellipsoidal scattering model is proposed for mobile-to-mobile communication channels, where uniformly distributed scatterers are assumed to be confined within the semi-ellipsoids around mobile stations. The semi-ellipsoidal shape with adju...