Search results for " telecomunicazioni"
showing 10 items of 245 documents
MAC–Engine: a new architecture for executing MAC algorithms on commodity WiFi hardware
2011
In this demo, we prove that the flexibility supported by off–the–shelf IEEE 802.11 hardware can be significantly ex- tended if we move the control of the MAC programming interface from the driver to the firmware, i.e. from the host CPU to the card CPU. To this purpose, we introduce the concept of MAC–Engine, that is an executor of Pro- grammable Finite State Machines (PFSM) implemented at the firmware level: we show how the card itself can support different protocol logics thanks to PFSM bytecode repre- sentations that can be dynamically injected inside the card memory at run-time without incurring in down time issues or network disconnect events. We provide different PFSM examples in order…
INDOOR LOCALIZATION USING COGNITIVE RADIOS AND SOFTWARE-DEFINED WIRELESS NETWORKS
Distributed Authentication and Authorization Architecture for Multi-service, Multi-provider Networks
2007
Flexible and Modular Support for Multicast Rate Adaptation in WLANs
2013
The flexibility and virtualization capabilities provided by wireless cards have received significant attention as a means to reduce development costs. In this paper we present a modular architecture that exploits the features provided by emerging PHY and MAC implementations to rapidly develop new rate adaptation algorithms for multicast trans- mission in wireless LANs. We validate our solution by developing three rate adapta- tion algorithms that use an innovative sensing mechanism to evaluate the frame recep- tion correlation of the members of the multicast group. The experimental results obtained on a real-life testbed show that our solutions permit to increase the performance of multicas…
Correlation-Based Similarity Metric For Clustering In Multimedia Social Network
2011
A low cost INS/GPS solution comparison for automotive mass market applications
2010
Architectures and Protocols for Flexible Physical Layers in Wireless Networks
Emerging wireless technologies are characterized by an increasing level of flexibility and programmability, not only in terms of core network functionalities, with the consolidated paradigms of software-defined-networks and function virtualization, but also in terms of radio access functionalities. Although the concept of software-defined PHY and MAC protocols is not new, exploiting flexibility at the lower layers of the protocol stack is not an easy task, because of complexity and performance constraints. Indeed, dealing with software-defined implementations of the radio implies managing complex software routines, often tightly inter-dependent and difficult to reuse, and poses some perform…
Offloading through Opportunistic Networks with Dynamic Content Requests
2014
Offloading is gaining momentum as a technique to overcome the cellular capacity crunch due to the surge of mobile data traffic demand. Multiple offloading techniques are currently under investigation, from modifications inside the cellular network architecture, to integration of multiple wireless broadband infrastructures, to exploiting direct communications between mobile devices. In this paper we focus on the latter type of offloading, and specifically on offloading through opportunistic networks. As opposed to most of the literature looking at this type of offloading, in this paper we consider the case where requests for content are non-synchronised, i.e. users request content at random …
Dynamic Adaptations of WiFi Channel Widths Without TX/RX Coordination
2017
Most modern standards for wireless communications support physical layer adaptations, in terms of dynamic selection of channel central frequency, transmission power, modulation format, etc., in order to increase link robustness under time-varying propagation and interference conditions. In this demo, we demonstrate that another powerful solution for extending physical layer flexibility in OFDM-based technologies is the dynamic adaptation of the channel width. Although some standards already define the possibility of utilizing multiple channel widths (e.g. 20MHz, 10MHz, 5MHz forIEEE 802.11a standards), such an utilization is limited to a static configuration of a value defined during the net…