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Full-Text Articles in Engineering
Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong
Blind Separation For Intermittent Sources Via Sparse Dictionary Learning, Annan Dong
Dissertations
Radio frequency sources are observed at a fusion center via sensor measurements made over slow flat-fading channels. The number of sources may be larger than the number of sensors, but their activity is sparse and intermittent with bursty transmission patterns. To account for this, sources are modeled as hidden Markov models with known or unknown parameters. The problem of blind source estimation in the absence of channel state information is tackled via a novel algorithm, consisting of a dictionary learning (DL) stage and a per-source stochastic filtering (PSF) stage. The two stages work in tandem, with the latter operating on …
Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese
Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese
Dissertations
The ability to distribute time and frequency among a large population of interacting agents is of interest for diverse disciplines, inasmuch as it enables to carry out complex cooperative tasks. In a wireless sensor network (WSN), time/frequency synchronization allows the implementation of distributed signal processing and coding techniques, and the realization of coordinated access to the shared wireless medium. Large multi-hop WSN's constitute a new regime for network synchronization, as they call for the development of scalable, fully distributed synchronization algorithms. While most of previous research focused on synchronization at the application layer, this thesis considers synchronization at the lowest …
Opportunistic Transmission Scheduling For Next Generation Wireless Communication Systems With Multimedia Services, Chengzhou Li
Opportunistic Transmission Scheduling For Next Generation Wireless Communication Systems With Multimedia Services, Chengzhou Li
Dissertations
The explosive growth of the Internet and the continued dramatic increase for all wireless services are fueling the demand for increased capacity, data rates, and support of different quality of service (QoS) requirements for different classes of services. Since in the current and future wireless communication infrastructures, the performances of the various services are strongly correlated, as the resources are shared among them, dynamic resource allocation methods should be employed. With the demand for high data rate and support of multiple QoS, the transmission scheduling plays a key role in the efficient resource allocation process in wireless systems. The fundamental …