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Device-to-Device (D2D) Communications

Firefighters responding to a fire in the mountain


The ability for a first responder to communicate is critical to the success of the operations. In certain situations, the coverage provided by the network infrastructure (i.e., cell towers) may be missing or insufficient and therefore it is crucial for public safety devices to be able to connect directly with each other. This feature was added to LTE starting with Release 12 of the 3GPP specifications, via the Proximity Services (ProSe), and further extended in Release 13. It supports device discovery, direct group communication, and UE-to-Network relay. Over the past several years, we have conducted extensive evaluation of LTE D2D and studies the impact of parameter configurations on the overall performance. The findings, published in peer-reviewed publications and NIST publications, provide operators and public safety agencies with guidelines on how to configure LTE D2D.

As technology evolves, 3GPP and network operators have been focusing on the standardization and deployment of 5G New Radio (NR), the next generation of cellular networks. It is imperative that the D2D capability remains accessible to first responders, which is why FirstNet and other public safety operators are actively working to add ProSe to NR by leveraging the D2D capabilities, called NR sidelink, developed for Vehicular-to-Anything (V2X) communication. Our current efforts focus on understanding, evaluating, and improving the performance of NR sidelink in the context of public safety scenarios. We are particularly interested in mechanisms related to physical layer, quality of service, resource allocation, and coexistence between LTE and NR, all of which important factors to improve coverage and capacity.


5G NR-based D2D research

  • Gamboa, S., Ben Mosbah, A., Garey, W., Liu, C., Rouil, R., "System-Level Evaluation of 5G NR UE-Based Relays" in 2023 IEEE Military Communications Conference (MILCOM), [Access paper
  • Liu, P. , Shen, C. , Liu, C. , Cintron, F. , Zhang, L. , Cao, L. , Rouil, R. and Roy, S., "Towards 5G New Radio Sidelink Communications: a Versatile Link-Level Simulator and Performance Evaluation" in Computer Communications, August 2023, [Access paper]
  • Liu, P. , Shen, C. , Liu, C. , Cintron, F. , Zhang, L. , Cao, L. , Rouil, R. and Roy, S., "5G New Radio Sidelink Link-Level Simulator and Performance Analysis" in The 25th International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems, Montreal, CA, [Access paper]
  • F.J. Cintrón, D. W. Griffith, C. Liu, R. A. Rouil, Y. Sun, J. Wang, P. Liu, C. Shen, A. Ben Mosbah, S. Gamboa Quintiliani, “Study of 5G New Radio (NR) Support for Direct Mode Communications”, Gaithersburg, MD, USA, May 2021. [Access paper]
  • Z. Ali, S. Lagén, L. Giupponi and R. Rouil, “3GPP NR V2X Mode 2: Overview, Models and System-Level Evaluation,” in IEEE Access, vol. 9, pp. 89554-89579, 2021, doi: 10.1109/ACCESS.2021.3090855. [Access paper]

LTE-based D2D research


  • J. Wang and R. Rouil, “BLER Performance Evaluation of LTE Device-to-Device Communications,” Gaithersburg, MD, USA, Nov. 2016. [Access paper]
  • D. W. Griffith, F. J. Cintron, and R. A. Rouil, “Physical Sidelink Control Channel (PSCCH) in Mode 2: Performance analysis,” in IEEE International Conference on Communications, 2017. [Access paper]
  • J. Wang and R. Rouil, “Assessing coverage and throughput for D2D communication,” in IEEE International Conference on Communications, 2018, vol. 2018–May. [Access paper]
  • D. Griffith, F. Cintrón, A. Galazka, T. Hall, and R. Rouil, “Modeling and simulation analysis of the physical sidelink shared channel (PSSCH),” in IEEE International Conference on Communications, 2018. [Access paper]
  • F. J. Cintron, “Performance evaluation of LTE device-to-device out-of-coverage communication with frequency hopping resource scheduling,” Gaithersburg, MD, USA, July 2018. [Access paper]
  • J. Wang, R. A. Rouil, and F. J. Cintron, “Distributed Resource Allocation Schemes for Out-of-Coverage D2D Communications,” 2019 IEEE Global Communications Conference (GLOBECOM), Waikoloa, HI, USA, 2019, pp. 1-7. [Access paper]


  • D. Griffith and F. Lyons, “Optimizing the UE transmission probability for D2D direct discovery,” in 2016 IEEE Global Communications Conference, GLOBECOM 2016 - Proceedings, 2016. [Access paper]
  • D. W. Griffith, A. Ben Mosbah, and R. A. Rouil, “Group Discovery Time in Device-to-Device (D2D) Proximity Services (ProSe) Networks,” in IEEE Conference on Computer Communications (INFOCOM 2017), 2017. [Access paper]
  • A. Ben Mosbah, D. Griffith, and R. Rouil, “A novel adaptive transmission algorithm for Device-to-Device Direct Discovery,” in 2017 13th International Wireless Communications and Mobile Computing Conference, IWCMC 2017, 2017, pp. 177–182. [Access paper]
  • A. Ben Mosbah, D. Griffith, and R. Rouil, “Enhanced transmission algorithm for dynamic device-to-device direct discovery,” in CCNC 2018 - 2018 15th IEEE Annual Consumer Communications and Networking Conference, 2018, vol. 2018–January. [Access paper]
  • D. Griffith and A. Ben Mosbah, “On Upper Bounds for D2D Group Size,” 2019 IEEE Global Communications Conference (GLOBECOM), Waikoloa, HI, USA, 2019, pp. 1-6. [Access paper]


  • S. Gamboa Quintiliani, F. J. Cintrón, D. W. Griffith, and R. A. Rouil, “Impact of Timing on the Proximity Services (ProSe) Synchronization Function,” in 14th Annual IEEE Consumer Communications & Networking Conference (CCNC 2017), 2017. [Access paper]
  • S. Gamboa, F. J. Cintrón, D. Griffith, and R. Rouil, “Adaptive synchronization reference selection for out-of-coverage proximity services,” in IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC, 2018, vol. 2017–October. [Access paper]

UE-based Relay (discovery and communication)

  • S. Gamboa, R. Thanigaivel, and R. Rouil, "System Level Evaluation of UE-to-Network Relays in D2D-Enabled LTE Networks," 2019 IEEE 24th International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD), Limassol, Cyprus, 2019, pp. 1-7. [Access paper]
  • S. Gamboa, A. Moreaux, D. Griffith, and R. Rouil, "UE-to-Network Relay Discovery in ProSe-enabled LTE Networks," in proceedings of 2020 International Conference on Computing, Networking and Communications (ICNC), Big Island, HI, USA, 2020. [Access paper]
  • A. Ben Mosbah, S. Gamboa, and R. Rouil, "NIST TN 2144 Evaluation of Timers Related to ProSe-based UE-to-Network Relays", March 2021. [Access paper]
  • A. Moreaux, S. Gamboa, D. Griffith, and R. Rouil, "NIST TN 2149 UE-to-Network Relay Model B Discovery in ProSe-Enabled LTE Networks", April 2021. [Access paper]


Wireless Systems Innovation and Performance Group

Created November 16, 2017, Updated March 5, 2024