Joint Power and Subcarrier Allocation Optimization for Multigroup Multicast Systems with Rate Splitting In this article, we investigate a resource allocation problem for multicarrier multiuser MISO (multipleinputSingleoutput) downlink systems, where multiple cochannel multicast groups are served simultaneously. We consider a ratesplitting transmission scheme to address the inevitable intergroup interference under an overloaded multigroup multicast scenario, where the insufficient number of transmit antennas prevents the conventional schemes from neutralizing the interference. We first formulate an optimization problem for maximizing the minimum multicast group rate among all groups on all available subcarriers. This problem involves a joint power and subcarrier allocation optimization, and is nonconvex. We apply an iterative scheme based on successive convex approximation (SCA) to find the locally optimal solution. Simulation results demonstrate the performance gain of the proposed scheme compared to the stateoftheart transmission schemes.

EnergyEfficient Hybrid Precoding Design for Integrated MulticastUnicast Millimeter Wave Communications with SWIPT In this paper, we investigate the energyefficient hybrid precoding design for integrated multicastunicast millimeter wave (mmWave) system, where the simultaneous wireless information and power transform is considered at receivers. We adopt two sparse radio frequency chain antenna structures at the base station (BS), i.e., fullyconnected and subarray structures, and design the codebookbased analog precoding according to the different structures. Then, we formulate a joint digital multicast, unicast precoding and power splitting ratio optimization problem to maximize the energy efficiency of the system, while the maximum transmit power at the BS and minimum harvested energy at receivers are considered. Due to its difficulty to directly solve the formulated problem, we equivalently transform the fractional objective function into a subtractive form one and propose a twoloop iterative algorithm to solve it. For the outer loop, the classic Bisection iterative algorithm is applied. For the inner loop, we transform the formulated problem into a convex one by successive convex approximation techniques and propose an iterative algorithm to solve it. Meanwhile, to reduce the complexity of the inner loop, we develop a zero forcing (ZF) techniquebased low complexity iterative algorithm. Specifically, the ZF technique is applied to cancel the interunicast interference and the first order Taylor approximation is used for the convexification of the nonconvex constraints in the original problem. Finally, simulation results are provided to compare the performance of the proposed algorithms under different schemes.