Managing the interference for down-link in LTE using fractional frequency reuse

Abstract

Long Term Evolution has developed a new radio technology called femtocell or Femto Base station; which is well-suited to improve cellular network capacity and mobile coverage to indoor user's areas. Providing additional capacity and coverage expansion through FBSs could lead to large interference in a cellular radio communication network. In this paper; we proposed an efficient resource allocation scheme based on Fraction Frequency Reuse (FFR) for interference mitigation; where the entire spectrum is shared among network entities. FFR mechanism aims to reduce co-tier and cross-tier downlink interferences by allocating non-overlapping sets of bands to the user equipment at different geographic locations. The main purpose of this work is to compare two main types of FFR schemes; respectively; Strict FFR and Soft Frequency Reuse with the proposed scheme. The three types of FFR schemes were explained and evaluated with Monte-Carlo simulation based on some performance metrics; namely; sum-rate; spectral efficiency; and outage probability. Simulation results showed that the impacts of the proposed scheme are significantly high in comparison with two other methods. The proposed scheme proved to enhance spectral efficiency; reduced the outage probability; and increased the sum rate for all the users.