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Tytuł:
Mathematical Foundations of Cognitive Radios
Autorzy:
Couillet, R.
Debbah, M.
Powiązania:
https://bibliotekanauki.pl/articles/308175.pdf
Data publikacji:
2009
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
Bayesian inference
cognitive radio
maximum entropy
Opis:
Recently, much interest has been directed towards software defined radios and embedded intelligence in telecommunication devices. However, no fundamental basis for cognitive radios has ever been proposed. In this paper, we introduce a fundamental vision of cognitive radios from a physical layer viewpoint. Specifically, our motivation in this work is to embed human-like intelligence in mobile wireless devices, following the three century-old work on Bayesian probability theory, the maximum entropy principle and minimal probability update. This allows us to partially answer such questions as, what are the signal detection capabilities of a wireless device, when facing a situation in which most parameters are missing, how to react and so on. As an introductory example, we will present previous works from the same authors following the cognitive framework, and especially the multi-antenna channel modeling and signal sensing.
Źródło:
Journal of Telecommunications and Information Technology; 2009, 4; 108-117
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal Voting Rule and Minimization of Total Error Rate in Cooperative Spectrum Sensing for Cognitive Radio Networks
Autorzy:
Ghosh, Samit Kumar
Trankatwar, Sachin Ravikant
Bachan, P.
Powiązania:
https://bibliotekanauki.pl/articles/1839471.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cognitive radio
energy detection
optimization
spectrum sensing
Opis:
In cognitive radio technology, spectrum sensing is essential for detecting spectrum holes which may be allotted to secondary users. In this paper, an optimal voting rule is used for cooperative spectrum sensing while minimizing the total error rate (TER). The proposed spectrum sensing method is more energy-efficient and may be implemented in practice. It is relied upon in an improved energy detector whose utilization depends on the presence or absence of the primary user. Expressions for false alarm and missed detection probabilities are derived in the paper as well. Overall performance is analyzed both for AWGN and Rayleigh fading channels, in the presence of additive white Gaussian noise (AWGN). The optimum voting rule is applied to the cooperative spectrum sensing process in order to identify the optimum number of sensing nodes and the detection threshold. Finally, an energy-efficient spectrum sensing algorithm is proposed, requiring a lower number of cognitive users for a given error bound.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 1; 43-50
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal Voting Rule and Minimization of Total Error Rate in Cooperative Spectrum Sensing for Cognitive Radio Networks
Autorzy:
Ghosh, Samit Kumar
Trankatwar, Sachin Ravikant
Bachan, P.
Powiązania:
https://bibliotekanauki.pl/articles/1839487.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cognitive radio
energy detection
optimization
spectrum sensing
Opis:
In cognitive radio technology, spectrum sensing is essential for detecting spectrum holes which may be allotted to secondary users. In this paper, an optimal voting rule is used for cooperative spectrum sensing while minimizing the total error rate (TER). The proposed spectrum sensing method is more energy-efficient and may be implemented in practice. It is relied upon in an improved energy detector whose utilization depends on the presence or absence of the primary user. Expressions for false alarm and missed detection probabilities are derived in the paper as well. Overall performance is analyzed both for AWGN and Rayleigh fading channels, in the presence of additive white Gaussian noise (AWGN). The optimum voting rule is applied to the cooperative spectrum sensing process in order to identify the optimum number of sensing nodes and the detection threshold. Finally, an energy-efficient spectrum sensing algorithm is proposed, requiring a lower number of cognitive users for a given error bound.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 1; 43-50
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implementation of Selected Spectrum Sensing Systems for Cognitive Radio Networks using FPGA Platform
Autorzy:
Abdullah, H. N.
Abed, H. S.
Powiązania:
https://bibliotekanauki.pl/articles/958080.pdf
Data publikacji:
2018
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cognitive radio
energy consumption
energy detection
FPGA
Opis:
The energy efficient spectrum sensing method is very important in cognitive radio (CR), since high power drain may limit its implementation in mobile applications. The spectrum sensing feature consumes more energy than other functional blocks, as it depends on continuous detection of the presence or absence of the primary user (PU). In this paper, we proposed two methods to reduce energy consumption of the spectrum sensing feature. The first is of a single stage variety with a reduced number of sensed samples. The other uses two stages. The first stage performs coarse sensing for many subchannels, and the best subchannel is forwarded for fine sensing in the second stage. The performance of the proposed methods is evaluated in AWGN channel and compared with the existing approach. The proposed methods are simulated using Matlab and ModelSim and are then hardware implemented using the Altera Cyclone II FPGA board. Simulation results show that the proposed methods offer an improvement in energy consumption with an acceptable reduction in the probability of detection. At Eb/N0 Eb/N0 Eb/N0 of 0 dB, the energy consumption is reduced by 50% and 72% in the first and second proposed method, respectively, compared to the traditional method (100% sensing).
Źródło:
Journal of Telecommunications and Information Technology; 2018, 4; 81-87
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
About Cognitive Radio Receiver under an Indoor Environment
Autorzy:
González, Ricardo Meneses
Powiązania:
https://bibliotekanauki.pl/articles/1193910.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Cognitive radio
indoor environment
spectrum hole
white space
Opis:
This small note makes an analysis of the current situation of the Cognitive Radio (CR) performance under an indoor environment. As well as, measurements of the electromagnetic environment in the 800-900 MHz UHF Band are carried out in a specific indoor environment, in order to discover a spectrum hole to be used by an cognitive radio unlicensed user.
Źródło:
World Scientific News; 2015, 22; 1-13
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radio Environment Map for the Cognitive Radio Network Simulator
Autorzy:
Bednarek, P.
Bicki, D.
Lopatka, J.
Powiązania:
https://bibliotekanauki.pl/articles/226843.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cognitive radio
Radio Environment Maps
REM database
G-REM
L-REM
Opis:
Military wireless tactical systems has faced the problem of limited spectrum resources. This is a reason why Cognitive Radio (CR) is one of the most popular topic studied by research institutes in the field of mobile telecommunications. CR technology is based on cognitive cycle, used for making decisions based on observation and orientation. To support this activity, radios need also information on current position, electromagnetic situation, legal issues etc. These functions can be provided by Radio Environment Map (REM) database. It enables more flexible spectrum utilization and coexistence of Primary and Secondary Users (PUs, SUs) without harmful interferences. This paper presents a proposal of REM database structure and graphical user interface (GUI). It also describes GUI implementation in MATLAB and data structure. Database was implemented using the database engine - SQLite. The proposed REM database is a part of cognitive radio network simulator developed in the Institute of Telecommunications.
Źródło:
International Journal of Electronics and Telecommunications; 2018, 64, 1; 45-49
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ICBCA – Improved Cluster Based Channel Allocation in Cognitive Radio Sensor Networks
Autorzy:
Agarkhed, Jayashree
Gatate, Veeranna
Powiązania:
https://bibliotekanauki.pl/articles/308481.pdf
Data publikacji:
2020
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
channel interference
channel overlapping
co-channel interference
cognitive radio
Opis:
Wireless sensor networks (WSNs) operate in an overcrowded electromagnetic environment, as the spectrum is shared by various wireless communication technologies. This gives rise to various challenges related to optimized and efficient spectrum utilization. Cognitive radio (CR) has emerged as a solution satisfying this requirement, as it is capable of adapting to the dynamic radio spectrum. Thanks to the deployment of cognitive radio in WSNs, the spectrum may be utilized in a more efficient manner. CR may identify the vacant channels dynamically, allowing the sensor nodes to effeectively communicate with each other. In this paper a clustering algorithm known as improved cluster-based channel assignment (ICBCA) is implemented, forming clusters of CR sensor nodes and then selecting vacant channels for data transmission purposes. Simulation results show that ICBCA outperforms existing clustering algorithms in CR sensor networks.
Źródło:
Journal of Telecommunications and Information Technology; 2020, 3; 28-35
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Power Allocation for Energy-Harvesting-based Fading Cognitive Multiple Access Channels : with or without Successive Interference Cancellation
Autorzy:
Li, Q.
Xu, D.
Powiązania:
https://bibliotekanauki.pl/articles/963855.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cognitive radio
power allocation
multiple access channels
energy harvesting
Opis:
This paper considers a fading cognitive multiple access channel (CMAC), where multiple secondary users (SUs), who share the spectrum with a primary user (PU), transmit to a cognitive base station (CBS). A power station is assumed to harvest energy from the nature and then provide power to the SUs. We investigate the power allocation problems for such a CMAC to maximize the SU sum rate under the interference power constraint, the sum transmit power constraint and the peak transmit power constraint of each individual SU. In particular, two scenarios are considered: with successive interference cancellation (SIC) and without SIC. For the first scenario, the optimal power allocation algorithm is derived. For the second scenario, a heuristic algorithm is proposed. We show that the proposed algorithm with SIC outperforms the algorithm without SIC in terms of the SU sum rate, while the algorithm without SIC outperforms the algorithm with SIC in terms of the number of admitted SUs for a high sum transmit power limit and a low peak transmit power limit of each individual SU.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 1; 65-72
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Spectrum Sensing Parameters in Cognitive Radio Using Adaptive Genetic Algorithm
Autorzy:
Chatterjee, S.
Dutta, S.
Bhattacharya, P. P.
Roy, J. S.
Powiązania:
https://bibliotekanauki.pl/articles/308511.pdf
Data publikacji:
2017
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
adaptive genetic algorithm
bandwidth
cognitive radio
spectrum sensing
throughput
Opis:
Quality of service parameters of cognitive radio, like, bandwidth, throughput and spectral efficiency are optimized using adaptive and demand based genetic algorithm. Simulation results show that the proposed method gives better real life solution to the cognitive radio network than other known approach.
Źródło:
Journal of Telecommunications and Information Technology; 2017, 1; 21-27
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cooperative games with incomplete information for Secondary Base Stations in cognitive radio networks
Autorzy:
Martyna, J.
Powiązania:
https://bibliotekanauki.pl/articles/308673.pdf
Data publikacji:
2013
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
Bayesian equilibrium
cognitive radio networks
game theory
wireless communication
Opis:
Cognitive radio (CR) technology is considered to be an effective solution for enhancing overall spectrum efficiency. Using CR technology fully involves the providing of incentives to Primary Radio Networks (PRNs) and revenue to the service provider so that Secondary Base Stations (SBSs) may utilize PRN spectrum bands accordingly. In this paper, a cooperative games with incomplete information for SBSs in a CR network is presented. Each SBS can cooperate with neighboring SBSs in order to improve its view of the spectrum. Moreover, proposed game-theory models assume that the devices have incomplete information about their components, meaning that some players do not completely know the structure of the game. Using the proposed algorithm, each SBS can leave or join the coalition while maximizing its overall utility. The simulation results illustrate that the proposed algorithm allows us to reduce the average payoff per SBS up to 140% relative to a CR network without cooperation among SBSs.
Źródło:
Journal of Telecommunications and Information Technology; 2013, 3; 106-111
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Employing a Savitzky-Golay Filtering Stage to Improve Performance of Spectrum Sensing in CR Applications Concerning VDSA Approach
Autorzy:
Angrisani, L.
Capriglione, D.
Cerro, G.
Ferrigno, L.
Miele, G.
Powiązania:
https://bibliotekanauki.pl/articles/220369.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cognitive radio
smoothing filter
VDSA
spectrum sensing
spectral measurements
Opis:
In this paper, a filtering stage based on employing a Savitzky-Golay (SG) filter is proposed to be used in the spectrum sensing phase of a Cognitive Radio (CR) communication paradigm for Vehicular Dynamic Spectrum Access (VDSA). It is used to smooth the acquired spectra, which constitute the input for a spectrum sensing algorithm. The sensing phase is necessary, since VDSA is based on an opportunistic approach to the spectral resource, and the opportunities are represented by the user-free spectrum zones, to be detected through the sensing phase. Each filter typology presents peculiarities in terms of its computational cost, de-noising ability and signal shape reconstruction. The SG filtering properties are compared with those of the linear Moving Average (MA) filter, widely used in the CR framework. Important improvements are proposed.
Źródło:
Metrology and Measurement Systems; 2016, 23, 2; 295-308
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mobility-Aware, Correlation-Based Node Grouping and Selection for Cooperative Spectrum Sensing
Autorzy:
Cichoń, K.
De Nardis, L.
Bogucka, H.
Di Benedetto, M. G.
Powiązania:
https://bibliotekanauki.pl/articles/307964.pdf
Data publikacji:
2014
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cognitive radio
cooperative spectrum sensing
mobility
node grouping
node selection
Opis:
Cooperative spectrum sensing has been proposed as a solution to increase the sensing function accuracy in cognitive radio networks, but the research has, so far, mainly focused on static scenarios, all but neglecting the impact of mobility on spectrum sensing. In this work a novel cooperative spectrum sensing scheme for mobile cognitive networks, based on a correlation-based, mobility-aware node selection algorithm is proposed. Correlation among sensing decisions is used to divide nodes into groups, and mobility is taken into account in the group leaders selection by means of a node selection metric that considers both sensing performance and mobility. Performance of the proposed algorithm is evaluated by computer simulations taking into account mobility and a detailed modeling of temporal and spatial correlation of fading and shadowing components in the channel path loss, going way beyond the performance evaluation carried out in previous works on correlation-based cooperative sensing schemes. Simulation results highlight that the proposed metric leads to a signicant increase of the update period required to maintain acceptable sensing performance, and correspondingly to a strong reduction in the overhead caused by the grouping and node selection procedure.
Źródło:
Journal of Telecommunications and Information Technology; 2014, 2; 90-102
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Suboptimal Approach to Distributed Detection in Cognitive Radio Networks
Autorzy:
Kumari, Shweta
Praveena, Sirimilla
Powiązania:
https://bibliotekanauki.pl/articles/1839473.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
cognitive radio
distributed detection
energy detector
myopic policy
spectrum sensing
Opis:
In this paper a dynamic spectrum access (DSA) concept is explored for mitigating the paucity of spectral bandwidth in cognitive radio (CR) for opportunistic, dynamic access of the spectrum without any interference. Dynamic spectrum access schemes are proposed for a distributed cognitive radio network consisting of one secondary user (SU) and many primary users (PUs). The SU has to make decisions for accessing PU channels within discrete time slots. The design of sensing and access strategies that govern channel choice in each slot for near-optimal throughput performance of the SU may be formulated as a partially observable Markov decision process (POMDP). Furthermore, it is considered that the SU incurs a cost whenever it switches to a different channel. The switching cost is expressed in terms of delay, packet loss and packet overhead. In this work, the SU access policy based on a myopic approach is proposed and evaluated.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 1; 32-36
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Integrating Two Feedback Queuing Discipline into Cognitive Radio Channel Aggregation
Autorzy:
Esenogho, E.
Mambou, E. N.
Ferreira, H. C.
Powiązania:
https://bibliotekanauki.pl/articles/226390.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cognitive radio
channel aggregation
primary and secondary users
queue discipline
Opis:
Queuing regime is one outstanding approach in improving channel aggregation. If well designed and incorporated with carefully selected parameters, it enhances the smooth rollout of fifth/next generation wireless networks. While channel aggregation is the merging of scattered TV white space (spectrum holes) into one usable chunk for secondary users (SU). The queuing regime ensures that these unlicensed users (SUs) traffic/services are not interrupted permanently (blocked/dropped or forced to terminate) in the event of the licensed users (primary user) arrival. However, SUs are not identical in terms of traffic class and bandwidth consumption hence, they are classified as real time and non-real time SU respectively. Several of these strategies have been studied considering queuing regime with a single feedback queuing discipline. In furtherance to previous proposed work with single feedback queuing regime, this paper proposes, develops and compares channel aggregation policies with two feedback queuing regimes for the different classes of SUs. The investigation aims at identifying the impacts of the twofeedback queuing regime on the performance of the secondary network such that any SU that has not completed its ongoing service are queued in their respective buffers. The performance is evaluated through a simulation framework. The results validate that with a well-designed queuing regime, capacity, access and other indices are improved with significant decrease in blocking and forced termination probabilities respectively.
Źródło:
International Journal of Electronics and Telecommunications; 2018, 64, 4; 519-525
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Perspektywy zagospodarowania widma radiowego w Polsce pod kątem implementacji radia kognitywnego
Spectrum management prospects in Poland in terms of the implementation of cognitive radio
Autorzy:
Grzybkowski, M. J.
Powiązania:
https://bibliotekanauki.pl/articles/317416.pdf
Data publikacji:
2012
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
radio kognitywne
widmo częstotliwości radiowych
zakresy częstotliwości
cognitive radio
radio spectrum
frequency bands
Opis:
W artykule przeanalizowano zakresy częstotliwości, które mogą być wykorzystane w systemach radia kognitywnego, przy założeniu obecnych i planowanych przeznaczeń częstotliwości w Polsce (w tym także w kontekście przeznaczeń europejskich) oraz istniejącego planu zagospodarowania poszczególnych zakresów częstotliwości. Analizę przeprowadzono uwzględniając możliwość wprowadzenia sieci radia kognitywnego w wybranych częściach widma, w tym w pasmach licencjonowanych oraz nielicencjonowanych, w sposób scentralizowany lub rozproszony.
The article analyzes the frequency bands which can be used by cognitive radio systems in the future, assuming the current and planned frequency allocation in Poland (including in the context of recommended European common allocations), and the existing frequency management plan. The analysis has been performed taking into account the possibility of implementation of cognitive radio networks in some parts of the radio spectrum, including licensed and unlicensed frequency bands., by the centralized or distributed method.
Źródło:
Telekomunikacja i Techniki Informacyjne; 2012, 1-2; 18-39
1640-1549
1899-8933
Pojawia się w:
Telekomunikacja i Techniki Informacyjne
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 39

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