多用户认知无线电系统中波束成形技术研究

In this paper，Multi-input multi-output (MIMO) technology provides the system with sharing space, increasing the degrees of freedom of space in addition to time and frequency, which can reduce interference to the primary user(PU)and improve the capacity of secondary user(SU). In this article, both of the primary base station(PBS) and the secondary base station(SBS) are equipped with multi-antennas. The PU receiver communicates to the SU transmitter the channel state information through the finite-rate feedback channel, so a cognitive beamforming(CB) algorithm based on the limited feedback is proposed. The expressions of the outage probability are presented. From the simulation results, it can be seen that the outage probability of both links is lower in this article. There exists a asymptotic value which the outage probability of SU is lower-bounded by.