human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "optimal energy beamforming under per antenna power constraint"):
  Abstract: Energy beamforming (EB) is a key technique to significantly enhance the efficiency of wireless power transfer (WPT). In this paper, we study optimal EB under per-antenna power constraint (PAC) which is more practical than conventional sum-power constraint (SPC) at multi antenna energy transmitter (ET). We consider a broadcast network, where one multi antenna ET with PAC, transfers wireless energy for energy receivers (ER)s which are randomly placed within the cell area. First, we consider sum energy maximization problem with PAC without fairness and provide the optimal solution structure for general case. This optimal structure implies that similar to SPC, sending one energy beam is optimal with PAC which means that the rank of transmit covariance matrix is one. We also derive closed-form solutions for two special cases and propose two sub-optimal solutions for general case, which are very close to optimal numerical results. To consider the fairness among the ERs, we further propose max-min fair problem with PAC, and analyze it for the special case of two transmit antennas. Simulation results show its advantages in comparison to the recent works in the literature.

Includes members:
  Member "wireless energy beamforming using received signal strength indicator feedback":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming")
  Member "distributed wireless power transfer with energy feedback":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming")
  Member "retrodirective multi user wireless power transfer with massive mimo":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "a retrodirective wireless power transfer scheme for ambient backscatter systems")
  Member "communications and signals design for wireless power transmission":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming")
  Member "wireless powered communication opportunities and challenges":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "wirelessly powered sensor networks power allocation for channel estimation and energy beamforming")
  Member "collaborative wireless energy and information transfer in interference channel":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "joint beamforming and power splitting design for c ran with multicast fronthaul")
  Member "enhancing wireless information and power transfer by exploiting multi antenna techniques":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "wireless energy beamforming using received signal strength indicator feedback")
  Member "multiuser mimo wireless energy transfer with coexisting opportunistic communication":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "cognitive wireless power transfer in the presence of reactive primary communication user")

Question: Please tell me which class the source paper belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.IT(Information Theory)