Crowdsourcing for mobile security : modelling, psychological bias, and performance of aggregation methods.

Abstract

The users demand for high speed broadband connectivity is increasing regardless of location and time. In particular, inside an aircraft, the in-flight connectivity is one of the last venues with no high-speed Internet access. This makes it an important research area to address for both industry and academia. By using the seamless gate-to-gate connectivity concept, passengers can stay connected in all phases of the flight by using 5G technologies. Given that the backhaul capacity will be provided via direct air-to-ground communications (DA2GC) links, passengers will be able to use both LTE and Wi-Fi access technologies on-board. In order to avoid interference with licensed ground LTE network, in-cabin LTE users will be served in the unlicensed spectrum via license assisted access (LAA) technology when the aircraft is close to the ground. However, in these bands other widely used incumbent technologies already exist, and consequently, this triggered research efforts from academia, industry, and standardization bodies to analyze the coexistence of these wireless technologies in the unlicensed band and the fair coexistence between them. This thesis targets the technical exploitation of air navigation and aeronautical data by modeling and analyzing the coexistence of wireless technologies in the unlicensed bands to address emerging challenges related to the harmonious coexistence of these networks. The thesis work is divided into three main parts. The first part analyzes the extension of the LTE technology toward the unlicensed bands. It studies the fair coexistence of LTE and Wi-Fi by considering the emerging IEEE 802.11ax Wi-Fi standard where stochastic geometry is used to model and analyze the coexistence of LTE with simultaneous uplink and downlink IEEE 802.11ax transmissions. Mainly, it considers LTE with continuous transmissions (no protocol change), LTE with discontinuous transmissions (LTE-U), and licensed assisted access (LAA) coexistence mechanisms. LAA has been adopted by 3GPP as a global LTE technology f