Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO

Haruhi Echigo, Tomoaki Ohtsuki

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Device-to-device (D2D) underlay massive multipleinput multiple-output (MIMO) is a notable technology to improve spectrum efficiency by using the same frequency among both cellular user equipments (CUEs) and D2D user equipments (DUEs). In terms of communication resources, it is required to avoid assigning orthogonal pilot sequences to all CUEs and DUEs. Although sharing the same pilot sequences among user equipments (UEs) can save the communication resources, interference arises among the same pilot sequences, which is known as pilot contamination. Because the impact of this interference is still large in the conventional pilot reuse, it is highly demanded to mitigate the effect of pilot contamination. In this paper, we propose a novel pilot reuse scheme based on a graph coloring technique to mitigate the effect of pilot contamination. By leveraging the fact that the interference is alleviated when the number of antennas is large and the angle of arrivals (AOAs) of the same pilot sequences does not overlap, our method assigns the same pilot sequences so that they are not overlapped. Furthermore, to improve the channel estimation accuracy between D2D pairs, our scheme restricts reusable pilot sequences by constructing an interference graph based on graph coloring. In this graph, the nodes near to each other are connected and assigned orthogonal pilot sequences. Simulation results show that the proposed scheme outperforms the conventional one in terms of channel estimation accuracy for UEs and spectral efficiency of the system.

Original languageEnglish
Title of host publication2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages1-6
Number of pages6
Volume2018-June
ISBN (Electronic)9781538663554
DOIs
Publication statusPublished - 2018 Jul 20
Event87th IEEE Vehicular Technology Conference, VTC Spring 2018 - Porto, Portugal
Duration: 2018 Jun 32018 Jun 6

Other

Other87th IEEE Vehicular Technology Conference, VTC Spring 2018
CountryPortugal
CityPorto
Period18/6/318/6/6

Fingerprint

Angle of Arrival
Graph Coloring
Coloring
Reuse
Output
Interference
Contamination
Channel estimation
Channel Estimation
Communication
Resources
Spectral Efficiency
Graph in graph theory
Assign
Antenna
Overlap
Sharing
Antennas
Vertex of a graph

ASJC Scopus subject areas

  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Applied Mathematics

Cite this

Echigo, H., & Ohtsuki, T. (2018). Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO. In 2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings (Vol. 2018-June, pp. 1-6). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/VTCSpring.2018.8417577

Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO. / Echigo, Haruhi; Ohtsuki, Tomoaki.

2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings. Vol. 2018-June Institute of Electrical and Electronics Engineers Inc., 2018. p. 1-6.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Echigo, H & Ohtsuki, T 2018, Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO. in 2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings. vol. 2018-June, Institute of Electrical and Electronics Engineers Inc., pp. 1-6, 87th IEEE Vehicular Technology Conference, VTC Spring 2018, Porto, Portugal, 18/6/3. https://doi.org/10.1109/VTCSpring.2018.8417577
Echigo H, Ohtsuki T. Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO. In 2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings. Vol. 2018-June. Institute of Electrical and Electronics Engineers Inc. 2018. p. 1-6 https://doi.org/10.1109/VTCSpring.2018.8417577
Echigo, Haruhi ; Ohtsuki, Tomoaki. / Graph Coloring-Based Pilot Reuse with AOA and Distance in D2D Underlay Massive MIMO. 2018 IEEE 87th Vehicular Technology Conference, VTC Spring 2018 - Proceedings. Vol. 2018-June Institute of Electrical and Electronics Engineers Inc., 2018. pp. 1-6
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