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: "random access protocol for massive mimo strongest user collision resolution sucr"
  Abstract: Wireless networks with many antennas at the base stations and multiplexing of many users, known as Massive MIMO systems, are key to handle the rapid growth of data traffic. As the number of users increases, the random access in contemporary networks will be flooded by user collisions. In this paper, we propose a reengineered random access protocol, coined strongest-user collision resolution (SUCR). It exploits the channel hardening feature of Massive MIMO channels to enable each user to detect collisions, determine how strong the contenders' channels are, and only keep transmitting if it has the strongest channel gain. The proposed SUCR protocol can quickly and distributively resolve the vast majority of all pilot collisions.

Connected through hyperedge HE-1 (induced by source paper "efficient pilot allocation for urllc traffic in 5g industrial iot networks"):
  with members:
    - "channel hardening in massive mimo a measurement based analysis"
    - "sparse signal processing for grant free massive connectivity a future paradigm for random access protocols in the internet of things"
    - "random access for massive mimo systems with intra cell pilot contamination"
    - "massive mimo for crowd scenarios a solution based on random access"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-2 (induced by source paper "success probability of grant free random access with massive mimo"):
  with members:
    - "massive multiple access based on superposition raptor codes for cellular m2m communications"
    - "random pilot and data access in massive mimo for machine type communications"
    - "random access preamble design and detection for 3gpp narrowband iot systems"
    - "rrh based massive mimo with on the fly pilot contamination control"
    - "random access protocols for massive mimo"
    - "a high throughput pilot allocation for m2m communication in crowded massive mimo systems"
    - "massive mimo for next generation wireless systems"
    - "emerging technologies and research challenges for 5g wireless networks"

Connected through hyperedge HE-3 (induced by source paper "virtual carrier sensing based random access in massive mimo systems"):
  with members:
    - "massive multiple access based on superposition raptor codes for cellular m2m communications"
    - "coded pilot access a random access solution for massive mimo systems"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "emerging technologies and research challenges for 5g wireless networks"
    - "five disruptive technology directions for 5g"

Connected through hyperedge HE-4 (induced by source paper "timing advance estimation and beamforming of random access response in crowded tdd massive mimo systems"):
  with members:
    - "a random access protocol for pilot allocation in crowded massive mimo systems"
    - "random access in uplink massive mimo systems how to exploit asynchronicity and excess antennas"
    - "what will 5g be"
    - "five disruptive technology directions for 5g"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-5 (induced by source paper "a random access protocol for pilot allocation in crowded massive mimo systems"):
  with members:
    - "random access in uplink massive mimo systems how to exploit asynchronicity and excess antennas"
    - "massive mimo ten myths and one critical question"
    - "random access for massive mimo systems with intra cell pilot contamination"
    - "massive mimo for crowd scenarios a solution based on random access"
    - "three practical aspects of massive mimo intermittent user activity pilot synchronism and asymmetric deployment"
    - "coded random access applying codes on graphs to design random access protocols"
    - "massive mimo systems with non ideal hardware energy efficiency estimation and capacity limits"
    - "coded random access how coding theory helps to build random access protocols"

Connected through hyperedge HE-6 (induced by source paper "random pilot and data access in massive mimo for machine type communications"):
  with members:
    - "a random access protocol for pilot allocation in crowded massive mimo systems"
    - "random access in uplink massive mimo systems how to exploit asynchronicity and excess antennas"
    - "coded pilot access a random access solution for massive mimo systems"
    - "massive mimo ten myths and one critical question"
    - "random access for massive mimo systems with intra cell pilot contamination"
    - "towards very large aperture massive mimo a measurement based study"
    - "massive mimo for crowd scenarios a solution based on random access"
    - "three practical aspects of massive mimo intermittent user activity pilot synchronism and asymmetric deployment"

Connected through hyperedge HE-7 (induced by source paper "random access protocols for massive mimo"):
  with members:
    - "a random access protocol for pilot allocation in crowded massive mimo systems"
    - "rrh based massive mimo with on the fly pilot contamination control"
    - "random access in uplink massive mimo systems how to exploit asynchronicity and excess antennas"
    - "coded pilot access a random access solution for massive mimo systems"
    - "random access for massive mimo systems with intra cell pilot contamination"
    - "coded random access applying codes on graphs to design random access protocols"
    - "coded random access how coding theory helps to build random access protocols"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-8 (induced by source paper "coded pilot access a random access solution for massive mimo systems"):
  with members:
    - "random access for massive mimo systems with intra cell pilot contamination"
    - "massive mimo for crowd scenarios a solution based on random access"
    - "coded random access how coding theory helps to build random access protocols"
    - "exploiting capture effect in frameless aloha for massive wireless random access"
    - "five disruptive technology directions for 5g"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "a coordinated approach to channel estimation in large scale multiple antenna systems"
    - "frameless aloha protocol for wireless networks"

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)