Mobile Communications Design Fundamentals
Mobile Communications Design Fundamentals
On Limits of Wireless Communications in a Fading Environment when UsingMultiple Antennas
Wireless Personal Communications: An International Journal
Fundamentals of wireless communication
Fundamentals of wireless communication
Modeling and analysis of interference in listen-before-talk spectrum access schemes
International Journal of Network Management
Fundamental design tradeoffs in cognitive radio systems
TAPAS '06 Proceedings of the first international workshop on Technology and policy for accessing spectrum
EURASIP Journal on Applied Signal Processing
Cooperative spectrum sensing based on the limiting eigenvalue ratio distribution in Wishart matrices
IEEE Communications Letters
Eigenvalue-based spectrum sensing algorithms for cognitive radio
IEEE Transactions on Communications
A review on spectrum sensing for cognitive radio: challenges and solutions
EURASIP Journal on Advances in Signal Processing - Special issue on advanced signal processing for cognitive radio networks
Spectrum characterization for opportunistic cognitive radio systems
MILCOM'06 Proceedings of the 2006 IEEE conference on Military communications
A measurement-based model for dynamic spectrum access in WLAN channels
MILCOM'06 Proceedings of the 2006 IEEE conference on Military communications
Spectrum sensing with forward methods
MILCOM'06 Proceedings of the 2006 IEEE conference on Military communications
A survey of spectrum sensing algorithms for cognitive radio applications
IEEE Communications Surveys & Tutorials
Cooperative Spectrum Sensing in Cognitive Radio, Part I: Two User Networks
IEEE Transactions on Wireless Communications
Cooperative Spectrum Sensing in Cognitive Radio, Part II: Multiuser Networks
IEEE Transactions on Wireless Communications
Reconfigurable terminals: an overview of architectural solutions
IEEE Communications Magazine
A bandwidth sharing approach to improve licensed spectrum utilization
IEEE Communications Magazine
Cognitive radio: brain-empowered wireless communications
IEEE Journal on Selected Areas in Communications
Capacity limits of cognitive radio with distributed and dynamic spectral activity
IEEE Journal on Selected Areas in Communications
Spectrum sensing: A distributed approach for cognitive terminals
IEEE Journal on Selected Areas in Communications
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In this paper, a two-phase algorithm for the spectrum sensing and power/rate control of a secondary user (S-user) or cognitive radio is proposed. In the first phase, the primary base station (P-BS), which is conscious of both the number and the data rate of primary active users (P-user), broadcasts theitusage capacity percentage (UCP) of its cell. Since knowing only the UCP is not enough to guarantee that the total load (of P-users and S-users) is less than a maximum permissible load, the S-user must measure the total interference received from both the P-users and other S-users. In this direction, using both the UCP and measurement of the interference received from the P-users and the S-users by the S-user or secondary base station (S-BS), we mathematically derive an equation for issuing data transmission permission, which if it is held then the second phase of the algorithm: the transmit power/rate control starts. In this phase, the S-user and the S-BS look for feasible values for the transmit power level and transmission rate. If there are feasible values, it starts its transmission at these feasible transmit power and rate. Since both the location of the S-user and the channel condition vary in time, the whole algorithm is iterated periodically with a period faster than the coherence time of the channel. Furthermore, we consider the down link of the above system with cooperation among neighboring S-users to overcome fading channels and we investigate the amount of improvement in the reliability of the issuing data transmission permission. As well, we consider the uplink of the system with multiple antennas in the S-BS to investigate the improvement in the same parameter over spatially correlated and independent fading channels. Theoretical analysis is validated using computer simulations. Both theoretical analysis and computer simulations show that the proposed cooperative spectrum sensing algorithm performs properly at SNR = −5dB in flat Nakagami-m fading channels with m = 1 even in correlated fading channels. We also address the improvement of the reliability of the issuing data transmission permission in the uplink in case of using multiple antennas only in the S-BS. Copyright © 2011 John Wiley & Sons, Ltd.