To provide enhance indoor coverage, Long Term Evolution (LTE) has been developed small cellular base stations called femtocells that can dramatically improve voice and data coverage for the indoor subscribers. Nevertheless, limited spectrum availability in the cellular networks causes severe interference issues in the neighboring femtocell users transmitting on the same sub-carriers. This paper proposed a Cluster-Aware Soft Frequency Reuse (CASFR) algorithm that assigns distinct set of Physical Resource Blocks (PRBs) to each interfering femtocells. According to algorithm first Femtocell Base Station (FBS) uses periodic messages from the femto user Equipment (FUE) to identify the interfering femtocells. It then divides each femtocell area into cell-center and cell-edge. Finally, it uses the CASFR algorithm to assign un-interfering sets of PRBs to the cell-center and cell-edge users of all the interfering femtocells. This is a very simple and efficient technique to mitigate uplink and downlink interference without wasting network resources thus improves performance for the overall femtocell network.

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Femto-cell Lte Sfr Casfr.