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: "opportunistic interference alignment in mimo interference channels"
  Abstract: We present two interference alignment techniques such that an opportunistic point-to-point multiple input multiple output (MIMO) link can reuse, without generating any additional interference, the same frequency band of a similar pre-existing primary link. In this scenario, we exploit the fact that under power constraints, although each radio maximizes independently its rate by water-filling on their channel transfer matrix singular values, frequently, not all of them are used. Therefore, by aligning the interference of the opportunistic radio it is possible to transmit at a significant rate while insuring zero-interference on the pre-existing link. We propose a linear pre-coder for a perfect interference alignment and a power allocation scheme which maximizes the individual data rate of the secondary link. Our numerical results show that significant data rates are achieved even for a reduced number of antennas.

Connected through hyperedge HE-1 (induced by source paper "cache enabled wireless networks with opportunistic interference alignment"):
  with members:
    - "caching at the wireless edge design aspects challenges and future directions"
    - "cache aided interference channels"
    - "distributed deep q learning"
    - "from spectrum pooling to space pooling opportunistic interference alignment in mimo cognitive networks"

Connected through hyperedge HE-2 (induced by source paper "convolutive superposition for multicarrier cognitive radio systems"):
  with members:
    - "what will 5g be"
    - "five disruptive technology directions for 5g"
    - "in band full duplex wireless challenges and opportunities"
    - "transmitting important bits and sailing high radio waves a decentralized cross layer approach to cooperative video transmission"
    - "cognitive radio an information theoretic perspective"

Connected through hyperedge HE-3 (induced by source paper "spatial sensing and cognitive radio communication in the presence of a k user interference primary network"):
  with members:
    - "on the degrees of freedom achievable through interference alignment in a mimo interference channel"
    - "cooperative algorithms for mimo interference channels"
    - "from spectrum pooling to space pooling opportunistic interference alignment in mimo cognitive networks"
    - "interference alignment with limited feedback"
    - "eigenvalue based spectrum sensing algorithms for cognitive radio"

Connected through hyperedge HE-4 (induced by source paper "user arrival in mimo interference alignment networks"):
  with members:
    - "settling the feasibility of interference alignment for the mimo interference channel the symmetric square case"
    - "mimo interference alignment over correlated channels with imperfect csi"
    - "cooperative algorithms for mimo interference channels"
    - "interference alignment as a rank constrained rank minimization"
    - "on feasibility of interference alignment in mimo interference networks"
    - "interference alignment with analog channel state feedback"
    - "interference alignment under limited feedback for mimo interference channels"
    - "on feasibility of interference alignment in mimo interference networks"

Connected through hyperedge HE-5 (induced by source paper "opportunistic interference mitigation achieves optimal degrees of freedom in wireless multi cell uplink networks"):
  with members:
    - "real interference alignment exploiting the potential of single antenna systems"
    - "parallel opportunistic routing in wireless networks"
    - "interference alignment with limited feedback on two cell interfering two user mimo mac"
    - "from spectrum pooling to space pooling opportunistic interference alignment in mimo cognitive networks"
    - "opportunistic relaying in wireless networks"
    - "ergodic interference alignment"
    - "opportunistic spatial orthogonalization and its application in fading cognitive radio networks"
    - "exploiting opportunistic multiuser detection in decentralized multiuser mimo systems"

Connected through hyperedge HE-6 (induced by source paper "mimo interference alignment over correlated channels with imperfect csi"):
  with members:
    - "cooperative algorithms for mimo interference channels"
    - "on feasibility of interference alignment in mimo interference networks"
    - "bit error rate is convex at high snr"
    - "on feasibility of interference alignment in mimo interference networks"
    - "the feasibility of interference alignment over measured mimo ofdm channels"
    - "on the achievability of interference alignment in the k user constant mimo interference channel"
    - "approaching the capacity of wireless networks through distributed interference alignment"
    - "a layered lattice coding scheme for a class of three user gaussian interference channels"

Connected through hyperedge HE-7 (induced by source paper "long term energy constraints and power control in cognitive radio networks"):
  with members:
    - "energy efficient precoding for multiple antenna terminals"
    - "introducing hierarchy in energy games"
    - "a game theoretic approach to energy efficient power control in multi carrier cdma systems"

Connected through hyperedge HE-8 (induced by source paper "from spectrum pooling to space pooling opportunistic interference alignment in mimo cognitive networks"):
  with members:
    - "asymptotic capacity and optimal precoding in mimo multi hop relay networks"
    - "interference alignment with limited feedback"
    - "on the achievability of interference alignment in the k user constant mimo interference channel"
    - "approaching the capacity of wireless networks through distributed interference alignment"
    - "asymptotic capacity and optimal precoding strategy of multi level precode forward in correlated channels"
    - "interference alignment on the deterministic channel and application to fully connected awgn interference networks"
    - "spectral efficiency of spectrum pooling systems"

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.GT(Computer Science and Game Theory)