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 "multi user flexible coordinated beamforming using lattice reduction for massive mimo systems"):
  Abstract: The application of precoding algorithms in multi-user massive multiple-input multiple-output (MU-Massive-MIMO) systems is restricted by the dimensionality constraint that the number of transmit antennas has to be greater than or equal to the total number of receive antennas. In this paper, a lattice reduction (LR)-aided flexible coordinated beamforming (LR-FlexCoBF) algorithm is proposed to overcome the dimensionality constraint in overloaded MU-Massive-MIMO systems. A random user selection scheme is integrated with the proposed LR-FlexCoBF to extend its application to MU-Massive-MIMO systems with arbitary overloading levels. Simulation results show that significant improvements in terms of bit error rate (BER) and sum-rate performances can be achieved by the proposed LR-FlexCoBF precoding algorithm.

Includes members:
  Member "robust adaptive beamforming using a low complexity shrinkage based mismatch estimation algorithm":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "study of coarse quantization aware block diagonalization algorithms for mimo systems with low resolution")
  Member "multi branch tomlinson harashima precoding design for mu mimo systems theory and algorithms":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "study of compressed randomized utv decompositions for low rank matrix approximations in data science")
  Member "generalized design of low complexity block diagonalization type precoding algorithms for multiuser mimo systems":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "study of coarse quantization aware block diagonalization algorithms for mimo systems with low resolution")
  Member "blind adaptive interference suppression based on set membership constrained constant modulus algorithms with dynamic bounds":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "study of sparsity aware set membership adaptive algorithms with adjustable penalties")
  Member "reduced rank doa estimation based on joint iterative subspace optimization and grid search":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "coordinate tomlinson harashima precoding design for overloaded multi user mimo systems")
  Member "massive mimo systems signal processing challenges and research trends":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "uplink downlink rate balancing and throughput scaling in fdd massive mimo systems")
  Member "scaling up mimo opportunities and challenges with very large arrays":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "adaptive distributed space time coding based on adjustable code matrices for cooperative mimo relaying systems":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "study of cloud aided multi way multiple antenna relaying with best user link selection and joint ml detection")

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)