PROJECT TITLE :

Frequency Partitioning Methods to Mitigate Cross-Tier Interference in Two-Tier Femtocell Networks

ABSTRACT:

Femtocells are enticing candidates for future cellular systems since they can greatly improve coverage and data rates. However, severe interference may occur and hinder the improved system performance due to a massive number of femtocells sharing frequency bands with the macrocell. In this paper, we have a tendency to consider the interference problem in two-tier femtocell networks and propose 2 frequency partitioning methods to mitigate the interference between the macrocell and femtocells. The key idea of the frequency partitioning ways is to partition the whole frequency band into many nonoverlapping components and allocate different components to the macrocell and femtocells in different regions. In the proposed methods, the downlink and uplink frequency bands are each divided into four nonoverlapping elements. The macrocell and femtocell are divided into three or four regions, with one part of the frequency band allotted to one region. With frequency and region partitioning, the users or base stations in one tier and the interfering users or base stations in the other tier are separated by a bound distance, that can greatly mitigate the interference. The most contribution of the proposed strategies is that the macrocell and femtocells will assign allocated resources to their own users independently, and also the cross-tier interference will be mitigated without difficult resource allocation or cooperation between the macrocell and femtocells. Moreover, we tend to theoretically analyze the existing interference and average per-channel rate performance of various users in different regions. Simulation results show that the theoretical analysis is cheap and that the proposed ways will successfully mitigate cross-tier interference.