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This paper presents an application of cognitive radio system concepts for the off-loading operation of LTE networks by the opportunistic use of TV whitespace (TVWS). A flexible functional architecture based on two cognitive managers for spectrum management and resource management respectively, and developed for various mobile scenarios, is mapped to the LTE network architecture. Corresponding system...
A spectrally modulated spectrally encoded (SMSE) based overlay cognitive radio has been implemented and demonstrated in [1] via GNU software define radio (SDR). However, like most of the current cognitive radio implementations and demonstrations, this work does not consider the mobility between cognitive radio nodes. In a high mobility environment, the frequency offset introduced by Doppler shift...
The development of mobile communication services has lead to the increase the use of wireless spectrum. However, the persuasion of the overly crowded spectrum is not due to the scarcity of usable radio frequencies but to the current static spectrum management policy. This reveals many idle frequency bands in both time and space. The cognitive radio network (CRN) is a key solution to exploit the existing...
In this paper we apply approximate and multiscale entropy metrics to spectrum occupancy data gathered during an extensive measurement campaign. We show that the presented methods can be successfully applied to search for and quantify structures of highly varying complexities and time scales. Although structures can be found they are unfortunately relatively complex and it does not appear to be easy...
Future wireless services are expected to provide data-rates in the order of 1 Gbps in local area and 100 Mbps in wide area. A very wide bandwidth is required to support such high rates, in the order of 100 MHz: this wideband will not be available for each operator, thus a shared access to the spectrum among operators is needed. An holistic approach to spectrum sharing is adopted in this paper: not...
We derive the Neyman-Pearson error exponent for the detection of Gauss-Markov signals using randomly spaced sensors. We assume that the sensor spacings, d1,d2,..., are drawn independently from a common density fd(.), and we treat both stationary and nonstationary Markov models. Error exponents are evaluated using specialized forms of the strong law of large numbers, and are seen to take on algebraically...
Huge interest and demand on information superhighway have pressed various telecommunications research fronts and lead to a new form of future Internet consisting of wired and wireless segments where resource-constrained devices such as palm pilots and sensors may become integral parts of the Internet rather than access-only platforms. One of the key design problems is the security in such heterogeneous...
In this paper, we propose a cognitive radio-based multi-user resource allocation framework for mobile ad hoc networks using multi-carrier DS CDMA modulation over a frequency-selective fading channel. In particular, given pre-existing communications in the spectrum where the system is operating, in addition to potential narrow-band interference, a channel sensing and estimation mechanism is provided...
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