The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In spite of the enormous popularity of Wi-Fi-enabled devices, the utilisation of Wi-Fi radio resources (e.g. RF spectrum and transmission power levels) at Access Points (APs) is degraded in current decentralised Radio Resource Management (RRM) schemes. Most state of the art centralised control solutions apply configurations in which the network-wide impacts of the involved parameters and their mutual...
The popularity of Wi-Fi-enabled devices alongside the growing demand for non-licensed spectrum, has made the Wi-Fi networks exceedingly congested. This endangers the efficiency of Wi-Fi and negatively affect the users' experience. The problem is especially pressing in dense areas (e.g. shopping centers) where Wi-Fi channel assignment is more likely to be uncoordinated and the working environment of...
This paper focuses on addressing the Access Point (AP) selection problem by relying on a centralized controller that provides a global view of the network. This approach follows the Software-Defined Networking (SDN) concept, which has long been considered in the literature as an innovative method to control management functionalities for wired networks and that is also now becoming a hot topic in...
This paper presents a real-time testbed based on reconfigurable devices able to transmit and receive data at different operating frequencies, which are dynamically configured. The main objective of this paper is to provide an advanced and realistic framework where the performance of algorithms and policies for spectrum selection in Cognitive Radio (CR) networks can be fully evaluated in a real-time...
Dynamic Spectrum Access, based on the Cognitive Radio (CR) paradigm, is a promising solution to improve the currently inefficient spectrum utilization. In this respect, this paper deals with the spectrum selection problem when a number of radio links has to be established in a CR network. A novel strategy based on a Partially Observable Markov Decision Process (POMDP) is proposed combining partial...
The demand for higher data rates, capacity and better Quality of Service (QoS) is constantly growing; therefore, there is a pressing need for efficient use of wireless network resources. In this context, the application of Cognitive Radio (CR) principle has emerged as a solution to the problem of spectrum scarcity. In this respect, this paper presents an algorithm that enables multi-band spectrum...
Dynamic Spectrum Access is a key capability of Cognitive Radio (CR) networks to increase the efficiency in the use of the available spectrum resources. In this respect, this paper focuses on the spectrum selection problem when a number of radio links has to be established in a CR network to support applications with different bit rate requirements. A novel strategy based on a Partially Observable...
Multimedia Broadcast/Multicast Services (MBMS), introduced in Universal Mobile Telecommunication System (UMTS), have the aim to allow transmissions from a single source entity to multiple destinations. From the radio perspective, MBMS foresees both point- to-point (PtP) and point-to-multipoint (PtM) transmission mode, supported by Dedicated, Common, and Shared channels. The High Speed Downlink Packet...
Multimedia broadcast multicast services (MBMS), introduced by Third Generation Partnership Project (3GPP) in universal mobile telecommunications system (UMTS) release 6 specification, have the aim to support downlink streaming and game services to groups of users. MBMS can supply users with resources in two different modalities: point-to-point (PtP) and point-to-multipoint (PtM). The power consumed...
Endothelial cells are involved in important pathological situations. They could be the target for infectious processes as for example in Cowdriosis, an important disease in cattle due to the rickettsia Cowdria ruminantium prevalent in the south of the Sahara. They are also connected to angiogenic processes related to tumor invasion. Our results indicate that AIDS related Kaposi sarcoma cells may be...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.