Abstract: A jointly optimize time and power allocation in uplink and downlink scheme combined with time reversal technique is proposed to solve the cross-link interference problem in multi-user wireless powered communication networks and maximize the uplink weighted sum-rate.Using the unique time-space focusing of time reversal to suppress the cross-link interference firstly,an optimization model is then established,thus the non-convex weighted sum-rate problem transformed into weighted minimum mean square error problem is solved.The optimal solution of power and time can be obtained separately by grading optimize variables sequentially.Simulations show that the system average sum-rate significantly improved after introducing the time reversal technique to suppress the cross-link interference.

Key words: wireless powered communication networks, cross-link interference, time reversal, sum-rate maximization