Abstract
Cognitive radio (CR) systems aim for more efficient spectrum utilization by having so called secondary user (SU) terminals transmit on a frequency band reserved for licensed primary user (PU) systems. The secondary transmissions are allowed provided that no harmful interference will be caused to the PUs. Equipping the SU terminals with multiple antennas enables them to use transmit precoding combined with power control in order to control the interference levels. In most of the previous works, perfect interference channel state information (CSI) has been assumed. With imperfect CSI, however, the SU is no longer able to guarantee that the interference constraint can be satisfied. In this paper, we investigate the problem of spectrum sharing with estimated CSI in CR systems using multiantenna terminals. Due to the randomness of the estimation error, we set a probabilistic interference constraint and, in order to satisfy it, analyze the interference power statistics. In addition, we provide a framework for transmit power control for satisfying this constraint. Moreover, we briefly cover the estimation-throughput tradeoff and numerically confirm that an optimal value for the estimation period can be obtained.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
