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: "degrees of freedom for mimo two way x relay channel"
  Abstract: We study the degrees of freedom (DOF) of a multiple-input multiple-output (MIMO) two-way X relay channel, where there are two groups of source nodes and one relay node, each equipped with multiple antennas, and each of the two source nodes in one group exchanges independent messages with the two source nodes in the other group via the relay node. It is assumed that every source node is equipped with   $M$    antennas while the relay is equipped with    $N$   antennas. We first show that the upper bound on the total DOF for this network is    $2\min\{2M, N\}$   and then focus on the case of   $N\leq 2M$    so that the DOF is upper bounded by twice the number of antennas at the relay. By applying signal alignment for network coding and joint transceiver design for interference cancellation, we show that this upper bound can be achieved when   $N\leq\lfloor{8M\over 5}\rfloor$  . We also show that with signal alignment only but no joint transceiver design, the upper bound is achievable when    $N\leq\lfloor{4M\over 3}\rfloor$  . Simulation results are provided to corroborate the theoretical results and to demonstrate the performance of the proposed scheme in the finite signal-to-noise ratio regime.

Connected through hyperedge HE-1 (induced by source paper "optimal dof region for the asymmetric two pair mimo two way relay channel"):
  with members:
    - "optimal degrees of freedom region for the asymmetric mimo y channel"
    - "generalized signal alignment on the achievable dof for multi user mimo two way relay channels"
    - "cyclic communication and the inseparability of mimo multi way relay channels"
    - "mimo multiway relaying with clustered full data exchange signal space alignment and degrees of freedom"
    - "mimo multiway relaying with pairwise data exchange a degrees of freedom perspective"
    - "generalized signal alignment for arbitrary mimo two way relay channels"
    - "approximate sum capacity of the y channel"
    - "degrees of freedom for the mimo multi way relay channel"

Connected through hyperedge HE-2 (induced by source paper "on the degrees of freedom of the symmetric multi relay mimo y channel"):
  with members:
    - "optimal degrees of freedom region for the asymmetric mimo y channel"
    - "generalized signal alignment on the achievable dof for multi user mimo two way relay channels"
    - "cyclic communication and the inseparability of mimo multi way relay channels"
    - "mimo multiway relaying with clustered full data exchange signal space alignment and degrees of freedom"
    - "beyond one way communication degrees of freedom of multi way relay mimo interference networks"
    - "mimo multiway relaying with pairwise data exchange a degrees of freedom perspective"
    - "approximate sum capacity of the y channel"
    - "degrees of freedom for the mimo multi way relay channel"

Connected through hyperedge HE-3 (induced by source paper "on the degrees of freedom of the large scale interfering two way relay network"):
  with members:
    - "what will 5g be"
    - "an algebraic approach to physical layer network coding"
    - "degrees of freedom of two hop wireless networks everyone gets the entire cake"
    - "opportunistic interference mitigation achieves optimal degrees of freedom in wireless multi cell uplink networks"
    - "reliable physical layer network coding"
    - "n k user interference channels degrees of freedom"
    - "a simple cooperative diversity method based on network path selection"

Connected through hyperedge HE-4 (induced by source paper "generalized signal alignment on the achievable dof for multi user mimo two way relay channels"):
  with members:
    - "a new dof upper bound and its achievability for k user mimo y channels"
    - "generalized signal alignment for mimo two way x relay channels"
    - "mimo multiway relaying with clustered full data exchange signal space alignment and degrees of freedom"
    - "beyond one way communication degrees of freedom of multi way relay mimo interference networks"
    - "mimo multiway relaying with pairwise data exchange a degrees of freedom perspective"
    - "generalized signal alignment for arbitrary mimo two way relay channels"
    - "degrees of freedom for the mimo multi way relay channel"
    - "the degrees of freedom of the mimo y channel"

Connected through hyperedge HE-5 (induced by source paper "degrees of freedom of the symmetric multi relay mimo y channel"):
  with members:
    - "generalized signal alignment on the achievable dof for multi user mimo two way relay channels"
    - "cyclic communication and the inseparability of mimo multi way relay channels"
    - "mimo multiway relaying with clustered full data exchange signal space alignment and degrees of freedom"
    - "beyond one way communication degrees of freedom of multi way relay mimo interference networks"
    - "mimo multiway relaying with pairwise data exchange a degrees of freedom perspective"
    - "approximate sum capacity of the y channel"
    - "degrees of freedom for the mimo multi way relay channel"
    - "multiple input multiple output two way relaying a space division approach"

Connected through hyperedge HE-6 (induced by source paper "beyond one way communication degrees of freedom of multi way relay mimo interference networks"):
  with members:
    - "degrees of freedom for the mimo multi way relay channel"
    - "the degrees of freedom of the mimo y channel"
    - "on the degrees of freedom achievable through interference alignment in a mimo interference channel"
    - "a feasibility test for linear interference alignment in mimo channels with constant coefficients"
    - "degrees of freedom of mimo x networks spatial scale invariance one sided decomposability and linear feasibility"
    - "subspace alignment chains and the degrees of freedom of the three user mimo interference channel"
    - "settling the feasibility of interference alignment for the mimo interference channel the symmetric square case"
    - "on feasibility of interference alignment in mimo interference networks"

Connected through hyperedge HE-7 (induced by source paper "mimo multiway relaying with clustered full data exchange signal space alignment and degrees of freedom"):
  with members:
    - "approximate sum capacity of the y channel"
    - "beamforming design for multiuser two way relaying a unified approach via max min sinr"
    - "degrees of freedom for the mimo multi way relay channel"
    - "multiple input multiple output two way relaying a space division approach"
    - "the capacity region of multiway relay channels over finite fields with full data exchange"
    - "subspace alignment chains and the degrees of freedom of the three user mimo interference channel"
    - "physical network coding in two way wireless relay channels"

Connected through hyperedge HE-8 (induced by source paper "generalized signal alignment for arbitrary mimo two way relay channels"):
  with members:
    - "generalized signal alignment for mimo two way x relay channels"
    - "mimo multiway relaying with pairwise data exchange a degrees of freedom perspective"
    - "approximate sum capacity of the y channel"
    - "degrees of freedom for the mimo multi way relay channel"
    - "divide and conquer approaching the capacity of the two pair bidirectional gaussian relay network"
    - "degrees of freedom region for the mimo x 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)