Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248281
Jungsun Um, Sunghyun Hwang, B. Jeong
Cognitive radio is widely expected to be a promising technology to efficiently exploit underutilized spectrum. Regulatory committees in many countries are taking into account the spectrum policy of dynamic spectrum access using this technology. The TV band is under consideration as a first step to share the spectrum resource. As a result, many activities to specify a standard using this band have been shown. In this paper, an overview on the physical layer of Ecma-392 standard and IEEE 802.11af draft standard is presented together with software simulated performance results. Furthermore, the effect of the frequency diversity on different number of subcarriers and channel bandwidth is analyzed and discussed.
{"title":"A comparison of PHY layer on the Ecma-392 and IEEE 802.1 laf standards","authors":"Jungsun Um, Sunghyun Hwang, B. Jeong","doi":"10.4108/ICST.CROWNCOM.2012.248281","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248281","url":null,"abstract":"Cognitive radio is widely expected to be a promising technology to efficiently exploit underutilized spectrum. Regulatory committees in many countries are taking into account the spectrum policy of dynamic spectrum access using this technology. The TV band is under consideration as a first step to share the spectrum resource. As a result, many activities to specify a standard using this band have been shown. In this paper, an overview on the physical layer of Ecma-392 standard and IEEE 802.11af draft standard is presented together with software simulated performance results. Furthermore, the effect of the frequency diversity on different number of subcarriers and channel bandwidth is analyzed and discussed.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130722139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248462
P. S. Coutinho, Marcel William Rocha da Silva, J. Rezende
Spectrum handoff is a key mechanism for proper and efficient operation of cognitive radios. A handoff occurs when the current operating channel must be freed by secondary users due to the arrival of a primary user. This mechanism is responsible for searching for a new idle licensed channel for secondary use, a task known as channel selection. The order in which the channels are sensed during the handoff has a great impact on performance. This paper proposes a new spectrum handoff scheme that considers the existence of errors in primary user detection to achieve a better channel ordering in terms of spectrum utilization efficiency and primary user interference. Simulation results show that the proposed mechanism outperforms other mechanisms from the literature.
{"title":"Detection error aware spectrum handoff mechanism for cognitive radios","authors":"P. S. Coutinho, Marcel William Rocha da Silva, J. Rezende","doi":"10.4108/ICST.CROWNCOM.2012.248462","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248462","url":null,"abstract":"Spectrum handoff is a key mechanism for proper and efficient operation of cognitive radios. A handoff occurs when the current operating channel must be freed by secondary users due to the arrival of a primary user. This mechanism is responsible for searching for a new idle licensed channel for secondary use, a task known as channel selection. The order in which the channels are sensed during the handoff has a great impact on performance. This paper proposes a new spectrum handoff scheme that considers the existence of errors in primary user detection to achieve a better channel ordering in terms of spectrum utilization efficiency and primary user interference. Simulation results show that the proposed mechanism outperforms other mechanisms from the literature.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"774 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133401115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248723
A. Polydoros, I. Dagres
It is well known that noise-modeling uncertainties give rise to a fundamental limit on the sensitivity of energy-based detectors (or related moment-based detectors), also known as the “SNR wall”. Similar “walls” appear also when localizing unknown sources for various applications (including cognitive radio), since localization techniques are based on tempo-spatial signal features. Low SNR regimes plus vague knowledge of the characteristics of the signal under detection in such applications motivate the exploration of techniques that are robust to such parameter uncertainties and therefore immune to such limits. A simple conceptual framework is proposed herein that naturally generates techniques with such immunity advantages for detecting the presence of an unknown source in broadband noise. At the cost of longer observation time, they allow SNR-wall-free detection. They also lend themselves to precise analysis and parametric optimization.
{"title":"Estimation-based noise-robust sensing","authors":"A. Polydoros, I. Dagres","doi":"10.4108/ICST.CROWNCOM.2012.248723","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248723","url":null,"abstract":"It is well known that noise-modeling uncertainties give rise to a fundamental limit on the sensitivity of energy-based detectors (or related moment-based detectors), also known as the “SNR wall”. Similar “walls” appear also when localizing unknown sources for various applications (including cognitive radio), since localization techniques are based on tempo-spatial signal features. Low SNR regimes plus vague knowledge of the characteristics of the signal under detection in such applications motivate the exploration of techniques that are robust to such parameter uncertainties and therefore immune to such limits. A simple conceptual framework is proposed herein that naturally generates techniques with such immunity advantages for detecting the presence of an unknown source in broadband noise. At the cost of longer observation time, they allow SNR-wall-free detection. They also lend themselves to precise analysis and parametric optimization.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130013134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.249480
Liang Yang, Mohamed-Slim Alouini, K. Qaraqe
In this paper, we study the capacity of spectrum sharing (SS) multiple-input multiple-output (MIMO) systems over Rayleigh fading channels. More specifically, we present closed-form capacity formulas for such systems with and without optimal power and rate adaptation. A lower bound on the capacity is also derived to characterize the scaling law of the capacity. Results show that increasing the number of antennas has a negative effect on the system capacity in the low signal-to-noise (SNR) regime and the scaling law at high SNR is similar to the conventional MIMO systems. In addition, a lower bound on the capacity of the SS keyhole MIMO channels is analyzed. We also present a capacity analysis of SS MIMO maximal ratio combining (MRC) systems and the results show that the capacity of such systems always decreases with the increase of the number of antennas. Numerical results are finally given to illustrate our analysis.
{"title":"On the performance of spectrum sharing systems with multiple antennas","authors":"Liang Yang, Mohamed-Slim Alouini, K. Qaraqe","doi":"10.4108/ICST.CROWNCOM.2012.249480","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.249480","url":null,"abstract":"In this paper, we study the capacity of spectrum sharing (SS) multiple-input multiple-output (MIMO) systems over Rayleigh fading channels. More specifically, we present closed-form capacity formulas for such systems with and without optimal power and rate adaptation. A lower bound on the capacity is also derived to characterize the scaling law of the capacity. Results show that increasing the number of antennas has a negative effect on the system capacity in the low signal-to-noise (SNR) regime and the scaling law at high SNR is similar to the conventional MIMO systems. In addition, a lower bound on the capacity of the SS keyhole MIMO channels is analyzed. We also present a capacity analysis of SS MIMO maximal ratio combining (MRC) systems and the results show that the capacity of such systems always decreases with the increase of the number of antennas. Numerical results are finally given to illustrate our analysis.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131237549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248483
S. L. Castellanos-Lopez, F. A. Cruz-Pérez, M. E. Rivero-Angeles, G. Hernández-Valdez
In this paper, the relevance of considering the primary network resource occupancy information on the admission criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call admission control (CAC) strategies whose admission criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.
{"title":"Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic","authors":"S. L. Castellanos-Lopez, F. A. Cruz-Pérez, M. E. Rivero-Angeles, G. Hernández-Valdez","doi":"10.4108/ICST.CROWNCOM.2012.248483","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248483","url":null,"abstract":"In this paper, the relevance of considering the primary network resource occupancy information on the admission criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call admission control (CAC) strategies whose admission criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122553778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248393
Salim Eryigit, T. Tuğcu
Cooperation among several secondary users for successful spectrum sensing defines an upper bound on the number of channels that can be sensed. Consequently, the maximum utilization is bounded by the number of sensing nodes rather than the availability of the channels. Hence, a subset of the channels should be selected based on the traffic requirements, and the secondary users should be assigned to those channels for the sensing task. In addition, secondary users experience different channel conditions due to interference, noise, and geographical location. Therefore, a secondary user should be assigned to a channel for which its sensing metrics are satisfactory. In this paper, we consider the problem of channel and user selection for cooperative sensing task. We model the mentioned channel selection and user assignment problem as a non-linear optimization problem and solve it using two alternative objectives to achieve increased throughput and number of satisfied users.
{"title":"Joint channel and user selection for transmission and sensing in cognitive radio networks","authors":"Salim Eryigit, T. Tuğcu","doi":"10.4108/ICST.CROWNCOM.2012.248393","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248393","url":null,"abstract":"Cooperation among several secondary users for successful spectrum sensing defines an upper bound on the number of channels that can be sensed. Consequently, the maximum utilization is bounded by the number of sensing nodes rather than the availability of the channels. Hence, a subset of the channels should be selected based on the traffic requirements, and the secondary users should be assigned to those channels for the sensing task. In addition, secondary users experience different channel conditions due to interference, noise, and geographical location. Therefore, a secondary user should be assigned to a channel for which its sensing metrics are satisfactory. In this paper, we consider the problem of channel and user selection for cooperative sensing task. We model the mentioned channel selection and user assignment problem as a non-linear optimization problem and solve it using two alternative objectives to achieve increased throughput and number of satisfied users.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131798146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248482
S. L. Castellanos-Lopez, F. A. Cruz-Pérez, G. Hernández-Valdez
In this paper, channel reservation to prioritize ongoing secondary users' (SUs) calls over new SUs' requests in cognitive radio networks (CRNs) with delay tolerant traffic and the RESTART (also known as preemptive repeat identical) retransmission strategy is analyzed and evaluated. Additionally, an analytical approach to approximately evaluate the performance of CRNs under the RESTART retransmission strategy is proposed and developed. It is shown that channel reservation is an effective mechanism both to reduce the negative impact of retransmissions and to widen the conditions under which system stability can be achieved. To the best of the authors' knowledge, mechanisms to modify the failure process in CRNs have been neither analyzed nor evaluated in the literature.
{"title":"Channel reservation in cognitive radio networks with the RESTART retransmission strategy","authors":"S. L. Castellanos-Lopez, F. A. Cruz-Pérez, G. Hernández-Valdez","doi":"10.4108/ICST.CROWNCOM.2012.248482","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248482","url":null,"abstract":"In this paper, channel reservation to prioritize ongoing secondary users' (SUs) calls over new SUs' requests in cognitive radio networks (CRNs) with delay tolerant traffic and the RESTART (also known as preemptive repeat identical) retransmission strategy is analyzed and evaluated. Additionally, an analytical approach to approximately evaluate the performance of CRNs under the RESTART retransmission strategy is proposed and developed. It is shown that channel reservation is an effective mechanism both to reduce the negative impact of retransmissions and to widen the conditions under which system stability can be achieved. To the best of the authors' knowledge, mechanisms to modify the failure process in CRNs have been neither analyzed nor evaluated in the literature.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127492413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.248116
Woongsup Lee, D. Cho
We consider the change of spectrum availability which is caused by the mobility of a cognitive radio (CR) user. Given that the CR user should not interfere with a primary user (PU), it should periodically check the availability of the CR band which is being used. Herein, we refer the scheme to check the availability of spectrum as SARS (Spectrum Availability Recheck Scheme). We propose a SARS for both CR systems which use a geo-location database to find vacant band and CR systems which use spectrum sensing to find vacant band. The proposed SARS adaptively changes its operation according to the velocity of a CR user. Through the analysis and the simulation results, we have shown that the spectrum availability of a CR user can be efficiently verified by using proposed SARS, when the CR user moves. We also have shown that the overheads caused by our SARS is low.
{"title":"Spectrum Availability Recheck Scheme (SARS) for cognitive radio systems with mobility","authors":"Woongsup Lee, D. Cho","doi":"10.4108/ICST.CROWNCOM.2012.248116","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.248116","url":null,"abstract":"We consider the change of spectrum availability which is caused by the mobility of a cognitive radio (CR) user. Given that the CR user should not interfere with a primary user (PU), it should periodically check the availability of the CR band which is being used. Herein, we refer the scheme to check the availability of spectrum as SARS (Spectrum Availability Recheck Scheme). We propose a SARS for both CR systems which use a geo-location database to find vacant band and CR systems which use spectrum sensing to find vacant band. The proposed SARS adaptively changes its operation according to the velocity of a CR user. Through the analysis and the simulation results, we have shown that the spectrum availability of a CR user can be efficiently verified by using proposed SARS, when the CR user moves. We also have shown that the overheads caused by our SARS is low.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126476426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-18DOI: 10.4108/ICST.CROWNCOM.2012.249475
Alexandros Palaios, Janne Riihijärvi, P. Mähönen, V. Atanasovski, L. Gavrilovska, P. V. Wesemael, A. Dejonghe, P. Scheele
In this paper we report on spectrum use measurements carried out synchronously over the period of 48+ hours in seven European cities. Special care has been placed on harmonizing the measurement settings and equipment so as to obtain as comparable data as possible. We describe in detail the measurement setup, including the coordinated preparation activities carried out across the different measurement sites. We present preliminary analysis of the obtained data set, and particularly highlight similarities and differences in spectrum use between selected measurement locations. We plan to release later the full data set for research community for the further research.
{"title":"Two days of spectrum use in Europe","authors":"Alexandros Palaios, Janne Riihijärvi, P. Mähönen, V. Atanasovski, L. Gavrilovska, P. V. Wesemael, A. Dejonghe, P. Scheele","doi":"10.4108/ICST.CROWNCOM.2012.249475","DOIUrl":"https://doi.org/10.4108/ICST.CROWNCOM.2012.249475","url":null,"abstract":"In this paper we report on spectrum use measurements carried out synchronously over the period of 48+ hours in seven European cities. Special care has been placed on harmonizing the measurement settings and equipment so as to obtain as comparable data as possible. We describe in detail the measurement setup, including the coordinated preparation activities carried out across the different measurement sites. We present preliminary analysis of the obtained data set, and particularly highlight similarities and differences in spectrum use between selected measurement locations. We plan to release later the full data set for research community for the further research.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132978450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-10DOI: 10.1109/ICC.2012.6363823
E. Stathakis, M. Skoglund, L. Rasmussen
A pair of secondary (cognitive, unlicensed) users is communicating in the presence of multiple primary (licensed) user pairs. The cognitive transceiver is implementing beamforming and orthogonal space-time block coding in the presence of external interference, induced by the primary system transmission, that has to be properly handled. Moreover, the cognitive link nodes, both the transmitter and the receiver, are supplied with different levels of network side information (NSI), i.e. primary messages and partial channel side information (CSI). We investigate how this side information can be taken into account in the cognitive system design and how interference affects the behaviour of the beamforming solution. Through numerical simulations, we illustrate the impact of partial CSI on system performance and discuss its implications on the feasibility of cognitive systems.
{"title":"On combined beamforming and OSTBC over the cognitive radio S-channel with partial CSI","authors":"E. Stathakis, M. Skoglund, L. Rasmussen","doi":"10.1109/ICC.2012.6363823","DOIUrl":"https://doi.org/10.1109/ICC.2012.6363823","url":null,"abstract":"A pair of secondary (cognitive, unlicensed) users is communicating in the presence of multiple primary (licensed) user pairs. The cognitive transceiver is implementing beamforming and orthogonal space-time block coding in the presence of external interference, induced by the primary system transmission, that has to be properly handled. Moreover, the cognitive link nodes, both the transmitter and the receiver, are supplied with different levels of network side information (NSI), i.e. primary messages and partial channel side information (CSI). We investigate how this side information can be taken into account in the cognitive system design and how interference affects the behaviour of the beamforming solution. Through numerical simulations, we illustrate the impact of partial CSI on system performance and discuss its implications on the feasibility of cognitive systems.","PeriodicalId":286843,"journal":{"name":"2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122683468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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