Current Issue : April - June Volume : 2017 Issue Number : 2 Articles : 6 Articles
A mobile coupon (m-coupon) can be presented with a smartphone for obtaining a financial discount when purchasing a product\nor a service. M-coupons are a powerful marketing tool that has enjoyed a huge growth and diffusion, involving tens of millions of\npeople each year. We propose an architecture which may enable significant improvements over current m-coupon technology, in\nterms of acceptance of potential customers and of marketing actions that become feasible: the customer does not need to install\nany dedicated app; an m-coupon is not bound to any specific device or customer; an m-coupon may be redeemed at any store in a\nset of potentially many thousands of stores, without any prior arrangement between customer and store. We are not aware of any\nproposal with these properties....
Mobile ad hoc networks are formed spontaneously to use the wireless medium for communication among nodes. Each node in this\ntype of network is its own authority and has an unpredictable behaviour. These features involve a cooperation challenge that has\nbeen addressed in previous proposals with methods based on virtual currencies. In this work, those methods have been simulated\nin NS-2 and the results have been analyzed, showing several weaknesses. In particular, it has been concluded that existent methods\ndo not provide significant advances compared with networks without any mechanism for promoting cooperation. Consequently,\nthis work presents three new proposals that try to solve those problems. The obtained results show that the new proposals offer\nsignificant improvements over previous schemes based on virtual currencies....
Similar to terrestrial networks, underwater wireless networks (UWNs) also aid several critical tasks including coastal surveillance,\nunderwater pollution detection, and other maritime applications.Currently, once underwater sensor nodes are deployed at different\nlevels of the sea, it is nearly impossible or very expensive to reconfigure the hardware, for example, battery. Taking this issue\ninto account, considerable amount of research has been carried out to ensure minimum energy costs and reliable communication\nbetween underwater nodes and base stations. As a result, several different network protocols were proposed for UWN, including\nMAC, PHY, transport, and routing. Recently, a new paradigm was introduced claiming that the intermittent nature of acoustic\nchannel and signal resulted in designing delay tolerant routing schemes for the UWN, known as an underwater delay tolerant\nnetwork. In this paper, we provide a comprehensive survey of underwater routing protocols with emphasis on the limitations,\nchallenges, and future open issues in the context of delay tolerant network routing....
Target tracking with the wireless sensors networks is to detect and locate a target on its entire path through a region of interest.\nThis application arouses interest in the world of research for its many fields of use. Wireless sensor networks, thanks to their\nversatility, can be used in many hostile and inaccessible to humans environments. However, with a limited energy, they cannot\nremain permanently active, which can significantly reduce their lifetime. The formation of a cluster network seems an effective\nmechanism to increase network lifetime. We propose to build optimal dynamic clusters on the target trajectory. For increasing\nenergy efficiency, our algorithm integrates for the first time, to our knowledge, strategies to avoid overlapping clusters and a model\nto wake up the sensors, adapting to the context of targets with large and variable speed....
Network Coding (NC) is confirmed to be power and bandwidth efficient technique,\nbecause of the less number of transmitted packets over the network.\nWireless Sensor Network (WSN) is usually power limited network application,\nand in many scenarios it is power and bandwidth limited application.\nThe proposed scenario in this paper applies the advantages of NC over WSN\nto obtain such power and bandwidth efficient WSN. To take the advantages of\nNC over the one of the most needed applications i.e. , WSN, we come up to\nwhat this paper is discussing. We consider a WSN (or its cluster) that consists\nof M nodes that transmit equal-length information packets to a common destination\nnode D over wireless Rayleigh block-fading channel where the instantaneous\nSNR is assumed to be constant over a single packet transmission\nperiod. Finite-State packet level Markov chain (FSMC) model is applied to\ngive the channel more practical aspect. The simulation results showed that\napplying NC over the WSN cluster improved the channel bandwidth significantly\nby decreasing the number of the Automatic Repeat Request (ARQ), resulting\nin improving the power consumption significantly. The results are\ncollected for different transmission distances to evaluate the behavior to the\nproposed scenario with regard to the bath losses effect....
A cognitive radio (CR) device likely consists of a low-cost low noise amplifier (LNA) due to the mass-production reason.\nNevertheless, the operation of a low-cost LNA becomes highly nonlinear causing intermodulation (IM) interference. The most\nimportant task of CR devices is to sense the wideband spectrum to increase opportunistic throughput. In noncooperative secondary\nnetworks, the IM interference usually can be ignored for the narrowband spectrum sensing, while the IM interference needs to be\ntaken into account along with interference from other CR devices in the wideband case. Our contribution is to study the effects of\na nonlinear LNA for the second case in environments modeled by Poisson field of interferers reflecting more realistic scenario. As\nshown in the simulation results, the performance of the receiver is degraded in all the cases due to the nonlinearity of LNA.The\nadaptive threshold setting based on the multivariate Gaussian mixture model is proposed to improve the receiver performance....
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