Subspace tracking based precoding algorithm for cognitive MIMO system
Guofeng Wu · Journal of Circuits and Systems · 2013
A precoding algorithm is proposed for the downlink of multi-user cognitive MIMO system in a slow fading channel circumstance.Exploiting the correlation of wireless channel in the time domain,the algorithm can track the wireless channel by updating the precoding matrix in a recursive manner based on the subspace tracking.The theoretical derivations and simulation analysis are completed from 4 aspects: the algorithm convergence rate,convergence precision,tracking capability of time-varying system and computation complexity.Simulations show that the proposed algorithm can track the dynamic changes of the wireless channel and it can reduce the complexity effectively,while guaranteeing its performance compared with traditional one.