December 09, 2018

Uplink ultra-reliable low latency communications assessment in unlicensed spectrum

  • Frederiksen F.
  • Pedersen K.
  • Roberto Maldonado
  • Rosa C.

Through this paper, the performance of uplink transmissions in terms of latency and reliability in unlicensed spectrum is addressed. Our goal is to provide insights into how ultra-reliable and low latency communications behave over the unlicensed spectrum in standalone mode. Our system model is based on the MulteFire radio access technology and operates in the 5 GHz unlicensed band. Grant-free is an alternative to scheduled uplink scheme aiming at reducing the latency of uplink transmissions. With grant-free uplink, the users can transmit their uplink data without needing a specific grant. In this paper, both grant-free and scheduled uplink are analyzed with a focus on their performance in unlicensed spectrum. Based on extensive system-level simulations, we prove that the grant-free approach is also suitable for latency reduction in the unlicensed spectrum under certain load conditions. Nevertheless, scheduled uplink presents some advantages when the number of grant-free users transmitting simultaneously increases.

Recent Publications

January 01, 2019

Friendly, appealing or both? Characterising user experience in sponsored search landing pages

  • Bron M.
  • Chute M.
  • Evans H.
  • Lalmas M.
  • Redi M.
  • Silvestri F.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Many of today's websites have recognised the importance of mobile friendly pages to keep users engaged and to provide a satisfying user experience. However, next to the experience provided by the sites themselves, ...

January 01, 2019

Analyzing uber's ride-sharing economy

  • Aiello L.
  • Djuric N.
  • Grbovic M.
  • Kooti F.
  • Lerman K.
  • Radosavljevic V.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Uber is a popular ride-sharing application that matches people who need a ride (or riders) with drivers who are willing to provide it using their personal vehicles. Despite its growing popularity, there exist ...

January 01, 2019

The paradigm-shift of social spambots: Evidence, theories, and tools for the arms race

  • Cresci S.
  • Petrocchi M.
  • Pietro R.
  • Spognardi A.
  • Tesconi M.

© 2017 International World Wide Web Conference Committee (IW3C2), published under Creative Commons CC BY 4.0 License. Recent studies in social media spam and automation provide anecdotal argumentation of the rise of a new generation of spambots, so-called social spambots. Here, for the first time, we extensively study this novel ...