Search

In automotive infotainment systems, vehicles using the applications are serviced via continuous infrastructure-to-vehicle (I2V) communications. Additionally, the I2V communications can be combined with vehicle-to-vehicle (V2V) connectivity owing to the small area covered by road side units (RSUs). However, dozens of vehicles have to compete for limited bandwidth when they request service simultaneously in the covered area. In this paper, we propose a joint scheduling and power control scheme for I2V and V2V links in the RSUs’ coverage range. Mapping the I2V and V2V links to tuple-links, we formulate a mixed-integer nonlinear programming (MINLP) problem where frequency scheduler and power controller for those tuple-links are jointly designed. Then, we employ the delayed column generation technique and the transmission pattern definition to decompose the MINLP problem into a transmission pattern scheduling problem, as well as a power control problem. Therein, the transmission pattern scheduling problem is solved by linear programming while a greedy power control algorithm is developed. Simulation results with practical parameter settings show that our proposed scheme outperforms several conventional schemes in terms of service disruption and achieved throughput while maintaining throughput fairness among the requesting vehicles. In particular, a high channel number, a small power level number, and a large buffer size at the requesting vehicles are shown to be helpful for our proposed scheme. [ABSTRACT FROM AUTHOR]

Efficiency maximization based on load optimization has been thoroughly investigated for the conventional single-input single-output (SISO) inductive power transfer (IPT) system. This paper further extends the problem for multiple-input multiple-output (MIMO) IPT system operating at a single frequency. For the MIMO IPT system, efficiency maximization requires a joint optimization of loads—at the receivers—and input currents—in the transmitters. The optimal complex values of input currents and loads are derived by applying the first-order necessary condition, followed by the second partial derivative test. The derived maximum efficiency expression enables performance evaluation for any coil configuration, under any coil arrangement and at any frequency. Effectiveness and feasibility of the derived formulas are evaluated by electromagnetic simulations. Our work generalizes a theory on efficiency maximization for SISO, single-input multiple-output, multiple-input single-output, and MIMO systems. [ABSTRACT FROM AUTHOR]