human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "transceiver design for dual hop nonregenerative mimo ofdm relay systems under channel uncertainties"
  Abstract: In this paper, linear transceiver design for dual-hop nonregenerative [amplify-and-forward (AF)] MIMO-OFDM systems under channel estimation errors is investigated. Second order moments of channel estimation errors in the two hops are first deduced. Then based on the Bayesian framework, joint design of linear forwarding matrix at the relay and equalizer at the destination under channel estimation errors is proposed to minimize the total mean-square-error (MSE) of the output signal at the destination. The optimal designs for both correlated and uncorrelated channel estimation errors are considered. The relationship with existing algorithms is also disclosed. Moreover, this design is extended to the joint design involving source precoder design. Simulation results show that the proposed design outperforms the design based on estimated channel state information only.

Connected through hyperedge HE-1 (induced by source paper "mmwave amplify and forward mimo relay networks with hybrid precoding combining design"):
  with members:
    - "low rf complexity technologies to enable millimeter wave mimo with large antenna array for 5g wireless communications"
    - "hybrid block diagonalization for massive multiuser mimo systems"
    - "spatially sparse precoding in millimeter wave mimo systems"
    - "distributed beamforming in wireless multiuser relay interference networks with quantized feedback"
    - "network beamforming using relays with perfect channel information"

Connected through hyperedge HE-2 (induced by source paper "a survey on mimo transmission with discrete input signals technical challenges advances and future trends"):
  with members:
    - "asymptotic performance analysis of a k hop amplify and forward relay mimo channel"
    - "iterative distributed minimum total mse approach for secure communications in mimo interference channels"
    - "asymptotic analysis of su mimo channels with transmitter noise and mismatched joint decoding"
    - "secure massive mimo transmission with an active eavesdropper"
    - "interference aligned space time transmission with diversity for the 2 times 2 x network"
    - "space time encoded miso broadcast channel with outdated csit an error rate and diversity performance analysis"
    - "high snr asymptotics of mutual information for discrete constellations with applications to bicm"
    - "differential distributed space time coding with imperfect synchronization in frequency selective channels"

Connected through hyperedge HE-3 (induced by source paper "on weighted mse model for mimo transceiver optimization"):
  with members:
    - "a framework for transceiver designs for multi hop communications with covariance shaping constraints"
    - "a general robust linear transceiver design for multi hop amplify and forward mimo relaying systems"
    - "matrix monotonic optimization for mimo systems"

Connected through hyperedge HE-4 (induced by source paper "a framework for transceiver designs for multi hop communications with covariance shaping constraints"):
  with members:
    - "evolution toward 5g multi tier cellular wireless networks an interference management perspective"
    - "beamforming for miso interference channels with qos and rf energy transfer"
    - "a general robust linear transceiver design for multi hop amplify and forward mimo relaying systems"
    - "matrix monotonic optimization for mimo systems"
    - "robust transceiver with tomlinson harashima precoding for amplify and forward mimo relaying systems"
    - "a tutorial on the optimization of amplify and forward mimo relay systems"
    - "ergodic capacity analysis of amplify and forward mimo dual hop systems"

Connected through hyperedge HE-5 (induced by source paper "matrix monotonic optimization for mimo systems"):
  with members:
    - "a general robust linear transceiver design for multi hop amplify and forward mimo relaying systems"
    - "robust transceiver with tomlinson harashima precoding for amplify and forward mimo relaying systems"
    - "robust transceiver design for af mimo relay systems with column correlations"
    - "a framework for designing mimo systems with decision feedback equalization or tomlinson harashima precoding"

Connected through hyperedge HE-6 (induced by source paper "a general robust linear transceiver design for multi hop amplify and forward mimo relaying systems"):
  with members:
    - "joint robust weighted lmmse transceiver design for dual hop af multiple antenna relay systems"
    - "robust transceiver design for af mimo relay systems with column correlations"
    - "ergodic capacity analysis of amplify and forward mimo dual hop systems"

Connected through hyperedge HE-7 (induced by source paper "how to understand lmmse transceiver design for mimo systems from quadratic matrix programming"):
  with members:
    - "cooperative beamforming for dual hop amplify and forward multi antenna relaying cellular networks"
    - "optimal energy allocation for wireless communications with energy harvesting constraints"

Connected through hyperedge HE-8 (induced by source paper "a tutorial on the optimization of amplify and forward mimo relay systems"):
  with members:
    - "power allocation in two hop amplify and forward mimo relay systems with qos requirements"
    - "asymptotic capacity and optimal precoding in mimo multi hop relay networks"
    - "achievable rate regions for bi directional relaying"
    - "diversity of mimo multihop relay channels"
    - "optimal space time codes for the mimo amplify and forward cooperative channel"

Question: Please tell me which class the center node 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)