Abstract-Recent efforts in satellite communication research considered the exploitation of higher frequency bands as a valuable alternative to conventional spectrum portions. An example of this can be provided by the Wband (70-110GHz). Recently, a scientific experiment carried on by the Italian Space Agency (ASI), namely the DAVID-DCE experiment, was aimed at exploring the technical feasibility of the exploitation of the W-band for broadband networking applications. Some preliminary results of DAVID research activities pointed out that phase noise and high Doppler-shift can severely compromise the efficiency of the modulation system, particularly for what concerns the aspects related to the carrier recovery. This problem becomes very critical when the use of spectrally efficient M-ary modulations is considered in order to profitably exploit the large amount of bandwidth available in the W-band. In this work 12 , a novel carrier recovery algorithm has been proposed for a 16-QAM modulation and tested, considering the presence of phase noise and other kinds of non-ideal behaviors of the communication devices typical of W-band satellite transmission. Simulation results demonstrated the effectiveness the proposed solution for carrier recovery and pointed out the achievable spectral efficiency of the transmission system, considering some constraints about transmitted power, data BER and receiver bandwidth.

The Bayesian filtering for recursive state estimation and the shape-based matching methods are two of the most commonly used approaches for target tracking. The Multiple Hypothesis Shape-based Tracking (MHST) algorithm, proposed by the authors in a previous work, combines these two techniques using the Particle Filter algorithm. The state of the object is represented by a vector of the target corners (i.e. points in the image with high curvature) and the multiple state configurations (particles) are propagated in time with a weight associated to their probability. In this paper we demonstrate that, in the MHST, the likelihood probability used to update the weights is equivalent to the voting mechanism for Generalized Hough Transform (GHT)-based tracking. This statement gives an evident explanation about the suitability of a MAP (Maximum a Posteriori) estimate from the posterior probability obtained using MHST. The validity of the assertion is verified on real sequences showing the differences between the MAP and the MMSE estimate.

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Abstract-In this paper a novel method to solve the fine synchronization problem in GNSS receivers is presented. In fact the extended evolution of GNSS-based applications will imply the growth of fast and precise navigation systems. The aim of this study is to found an alternative solution to the classical non-coherent Delay Lock Loop. In particular, the proposed method, based on Self Organizing Map (SOM) a particular type of Neural Networks, allows to improve the performances in multipath channel.

In this paper, a multi-camera architecture is presented for heterogeneous targets analysis and tracking. The proposed system can be switched in various configurations enabling automatic and human driven scene analysis. To achieve this, different control strategies have been implemented in order to optimize results in terms of perceptual image quality and pointing precisions.