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Bulk data dissemination is a basic building block for enabling software update and reprogramming in wireless sensor networks. The recent structure based approach looks promising for efficient dissemination since it facilitates transmission and sleep scheduling. However, a number of limitations exist in existing structured protocols. In this paper, we propose a correlated core based solution for efficient...
This paper investigates energy effectiveness problem for 802.11 n+ protocol in heterogeneous MIMO networks. Specifically, we consider a two-link network, where a 2 × 2 MIMO link transmits concurrently with an 1 × 1 link. We show that the completely cancelling out all the interference may result in an ineffective transmission for the incoming link. It consumes much energy on eliminating interference...
Phishing is a threat in which users are sent fake emails that urge them to click a link (URL) which takes to a phisher's website. At that site, users' accounts information could be lost. Many technical and non-technical solutions have been proposed to fight phishing attacks. To stop such attacks, it is important to select the correct feature(s) to detect phishing emails. Thus, the current work presents...
A new MATLAB-based, wireless measurement platform using an existing software-defined radio architecture is presented. It augments IEEE 802.11g MIMO-OFDM physical layer schemes with new designs such as Maximal Ratio Combining, Alamouti coding, and Spatial Multiplexing. The platform provides a series of metrics, including channel capacity, Error Vector Magnitude (EVM), and Post-Processing Signal-to-Noise...
Nonlinear precoding multi-user multiple-input multiple-output using vector perturbation (VP MU-MIMO) can provide good frequency efficiency at the cost of computational complexity, which exponentially increases as the number of spatial multiplexed users increases. This is because the original VP precoding requires to exhaustively search the optimum transmit signal vector among all the combinations...
Data from affordable body-sensor devices that monitor personal metrics like heart-rate, weight, and movements are changing how athletes train and perform. Existing sport-analytic tools are, however, mostly monolithic proprietary systems where athletes have little control over how their data is used and managed over time. This paper describes Girji, security centered body-sensor data acquisition and...
Conventional image and video communication systems are usually designed with the objective being to maximize the fidelity of reconstructed images measured by mean square errors (MSE). It is well known that the fidelity metric MSE may not reflect the visual quality perceived by human eyes. Recent advancements in image quality assessment tell us that the structural similarity (SSIM), especially the...
Reconfigurable radio frequency (RF) system is an emerging component to mitigate the growing engineering cost for wireless chip design. In this paper, we propose a new methodology for efficient programming of reconfigurable RF receiver. The proposed method is facilitated by two novel techniques: two-phase relaxation search and Pareto-based search space reduction. Our numerical experiments demonstrate...
The optimality of the conventional maximum-likelihood sequence estimation (MLSE), also known as the Viterbi Algorithm (VA), relies on the assumption that the receiver has perfect knowledge of the channel coefficients or channel state information (CSI). However, in practical situations that fail the assumption, the MLSE method becomes suboptimal and then exhaustive checking is the only way to obtain...
Processing massive data flow in intrusion detection systems (IDS) become a serious challenge. It is considered as a major deficiency while handling heterogeneous and non-stationary data stream to uncover anomaly in the online operational mode. This paper proposes a novel online method that constructs connections from the massive data flow for evaluating IDS models. The proposed method overcomes this...
The any cast routing protocol is useful in ad hoc and sensor networks as well as in the Internet. This study proposes an any cast routing protocol for ad hoc and sensor networks. The proposed method is lightweight and works with local information, which is obtainable at each node through advertisement packets transmitted from neighbor nodes. These characteristics are well suited to ad hoc and sensor...
Services to provide live streaming video from mobile sources are becoming widespread, including Ustream. It is expected that this type of services will be deployed particularly in local community networks using wireless mesh networks, in addition to the current services provided in the Internet. For providing live video streaming services in wireless mesh networks from mobile sources, adaptive multicast...
Dynamic spectrum access (DSA) is emerging as a promising technology to mitigate spectrum scarcity caused by static frequency allocation. Among the different models proposed for DSA, opportunistic spectrum access (OSA) is a promising class of solutions. In any DSA system, it is important to make sure that the performance of primary users (PUs) does not degrade significantly as a result of dynamic use...
Two recent advances in wireless communications are set to provide large gains in the efficient allocation of spectral resources. Multiuser detection (MUD) allows multiple transmitters to be allocated the same frequency band at the same time without spatial separation. In a packet-based standard such as 802.11, this would mean that packets could survive collisions, so the medium access controller (MAC)...
Distributed arrays provide a way to exploit MIMO and other array transmission and processing approaches using several single-antenna nodes connected via an Intra-Cluster Network (ICN). Recruitment of nodes within the transmit cluster for relaying a distributed space-time block code (STBC) transmission can be coordinated by a source node. Subject to synchronization and coherence recovery, when the...
In this work we propose a variation to the Block Diagonalization (BD) algorithm described that mitigates the interference from an external interference source which does not participate in the joint transmission inherent to the BD algorithm. The idea consists of precoding the signal at the transmission side so that the received signal at each receiver lies in a subspace orthogonal to the subspace...
We report results of measurements on SensLAB, an indoor wireless sensor network testbed with a large number of nodes equipped with a CC1101 radio chip. We analyze RSSI and LQI to find the best way to discriminate good links from weak ones and in particular, to derive a metric that estimates the Packet Reception Ratio (PRR) the best. To obtain an estimator of PRR, we have fitted a Fermi-Dirac function...
In device-to-device (D2D) communications underlaying uplink (UP) cellular networks, the channel state information (CSI) of interference links between regular cellular users (CUs) and D2D receivers is necessary to provide guaranteed quality-of-service (QoS) to D2D users. However, getting the CSI is very difficult and requires high overhead. In this paper, we propose a selected-K maximum distance ratio...
In this paper we address the design of MIMO double codebook structure for cross-polarized antenna arrays. Double codebooks consist of two codebook components, a wide-band long-term component and a short-term sub-band component. Herein we study particularly the two layer short-term sub-band component and provide the complete set of structure types leading to orthogonal constant modulus codewords and...
In our previous work, we proposed to use a vehicle network for data gathering, i.e. as an urban sensor. In this paper, we aim at understanding the theoretical limits of data gathering in a time slotted wireless network in terms of maximum service rate per node and end to end packet delivery ratio. The capacity of wireless networks has been widely studied and boundaries for that capacity expressed...
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