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 cognitive communication, dynamic sensing and opportunistic accessing enable secondary users to recognize and utilize the white spaces of the licensed bandwidth. Most present efforts focus on designing smarter channel sensing and access algorithms for secondary users to optimize the overall throughput and bandwidth utilization efficiency, without interfering with primary users' communication. However,...
In this paper, we investigate the optimal power allocation strategy for underlay-based cognitive radio networks (CRN) with statistical quality-of-service (QoS) protection of primary users (PU). Instead of utilizing commonly used average/peak interference power constraints to protect PU's transmission, our proposed power allocation strategy will satisfy PU's statistical QoS requirement characterized...
In cloud computing, it is important to protect user data. Thus, data owners usually encrypt their data before outsourcing them to the cloud server for security and privacy concerns. At the same time, very often users need to find data for specific keywords of interest to them. This motivates the research on the searchable encryption technique, which allows the search user to search over the encrypted...
Since its early beginnings, e-mail has been one of the most successful Internet services as it was the first to offer global, asynchronous and almost instant message delivery. However, at the same time e-mail has not been designed with strong security considerations in mind, leading to various problems related to unsolicited messages. In order to mitigate this situation, since the mid 2000s, domain-based...
In this work we analyze a quantum communication scheme for entanglement-based continuous variable quantum key distribution between two ground stations. Communication occurs via a satellite over two independent atmospheric fading channels dominated by turbulence-induced beam wander. In this scheme the engineering complexity remains largely on the ground transceivers, with the satellite acting simply...
Spam emails are considered as one of the biggest challenges for the Internet. Thus email classification, which aims to correctly classify legitimate and spam emails, becomes an important topic for both industry and academia. To achieve this goal, machine learning techniques, especially supervised machine learning algorithms, have been extensively applied to this field. In literature, several studies...
Unconditionally secure authentication schemes with an arbiter have been proposed in the literature. We extend this idea in the context of quantum authentication. In this paper, we present an unconditionally secure authentication scheme with an arbiter by using quantum principles. Compared to other arbitrated quantum schemes, our scheme is secure against denial by the sender of having sent a message...
In this paper, we propose a new method called Ambiguous Multi-Symmetric Cryptography (AMSC) that conceals multiple plain-texts in a cipher-text using the same number of keys. The goal of this method is to overcome the problem of symmetric cryptography failure when the shared key is exposed. The proposed method AMSC is a cryptographic primitive that preserves plausible deniability after a cryptographic...
In cognitive radio (CR) networks, spectrum sensing is an essential operation for unlicensed users to discover available spectrum opportunities for communications. However, current spectrum sensing techniques have a drawback that they can only detect the existence of signals but they cannot differentiate whether the detected signals come from licensed users or unlicensed users. This drawback leads...
Heterogeneous cellular networks are a promising approach in achieving better quality of service and coverage. They are also a relief for the exponentially increasing data traffic demand. Small cell access points (SAPs) typically rely on out-ofband communication links for backhaul which can be wired or wireless. In this paper, we investigate the price-based resource allocation problem in a self-backhauled...
This paper considers cooperation between primary and secondary users in shared spectrum radio networks via caching. A network consisting of a single macro (primary) base-station and multiple small (secondary) base-stations is considered. Secondary base-stations can cache some primary files and thereby satisfy content requests generated from nearby primary users. For this cooperative scenario, we develop...
Energy detection constitutes a popular sensing approach thanks to its relatively satisfactory performance at low complexity requirements. Its efficiency can be practically enhanced by employing diversity schemes which are also capable of providing adequate mitigation of multipath fading effects. Based on this, the present work is devoted to the analysis of energy detection based spectrum sensing over...
In this paper, we argue that the traditional techniques for flooding and probabilistic flooding are not applicable to cognitive radio networks under the SINR regime. We identify the causes that i) degrade node outreach even with increasing deployment density under the SINR model and ii) lead to duplicate transmissions under the Boolean model. Further performance degradation occurs due to the additional...
A wideband spectrum sensing method for cognitive radios is presented which is based on compressed measurements. The proposed detector does not require signal reconstruction from the compressed measurements. A fusion centre collects the measurements from different sensing nodes and then makes a sensing decision based on a simplified maximum likelihood criterion which does not require prior signal information...
Spectrum sensing is one of the key technologies to realize dynamic spectrum access in cognitive radio (CR). In this paper, a novel database-augmented spectrum sensing algorithm is proposed for a secondary access to the TV White Space (TVWS) spectrum. The proposed database-augmented sensing algorithm is based on an existing geo-location database approach for detecting incumbents like Digital Terrestrial...
In this paper, we investigate an online spectrum auction problem in cognitive radio networks with uncertain activities of primary users (PUs). In our framework, a primary base station (PBS), acted as the spectrum auctioneer, leases its under-utilized channels to secondary users (SUs) who request and access spectrum on the fly. Different from most of existing works in online spectrum allocation, we...
We study a multiple-antenna two-way relaying (TWR) spectrum sharing system. A space alignment (SA) technique is adopted by the secondary users (SU's) to avoid interference with the primary users (PU's). We derive the optimal power allocation that maximizes the TWR achievable sum-rate of the SU while respecting the total power budget and the relay power constraints. In the numerical results, we quantify...
Automatic Modulation Classification is a key technology in Cognitive Radio Networks. Blind identification of the modulation scheme of an unknown detected signal has various commercial and military applications. Performance of Automatic Modulation Classifiers degrades severely under low Signal-to-Noise ratios and fading channel scenarios. Cooperative classification is presented as a means to enhance...
As a distinctive feature of Information Centric Networking (ICN), in-network caching plays a fundamental role on system performance. The line-speed requirement of in-network caching invalidates the employ of complex collaborative caching schemes. The cache management of in-network caching includes three components - cache placement, cache replacement and cache location. Coupling the three pieces would...
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.