LTE frequency one re-use factor: Would it be an efficient solution for the unlicensed bands? A stochastic geometry analysis

Abstract

With the increasing demand on higher data rates to enhance the user experience, one possible solution would be to extend the cellular technology such as LTE toward the unlicensed bands. Initially, LTE was designed based on the frequency re-use factor of one and which has lead to higher capacity in several deployment scenarios. This happens when LTE exclusively uses the licensed spectrum where interference can be controlled. On the other hand, when LTE uses the unlicensed spectrum, other technologies such as WiFi will coexist and hence LTE will be subject to uncontrolled interference while it is expected to achieve a fair coexistence with such technologies. Given these constraints, we discuss in this paper the utilization of frequency re-use factor of one for LTE in the unlicensed band. In this case and subject to regulations of utilizing unlicensed bands, LTE will use the Listen before talk (LBT) mechanism with other radio access technologies. Thus, using tools from stochastic geometry, we model and analyze the effect of such scenario while comparing it to the case where LTE considers LBT mechanism with other LTE transmissions. Our analysis shows interesting performance gains that can be achieved by LTE in terms of rate coverage probability.