|Title||:||Improving Energy Efficiency and Mitigating Inter-cell Interference in Dense Femto Cell Networks|
|Speaker||:||Sudeepta Mishra (IITM)|
|Details||:||Tue, 29 Dec, 2015 2:00 PM @ BSB 361|
|Abstract:||:||A typical User Equipment (UE) suffers from low throughput and frequent call drops due to poor indoor cellular coverage from outdoor Base Stations (BSs). In order to improve the signal quality of an UE, a large number of outdoor BSs are required. However, this is not feasible due to high capital and operational expenditure. Hence, a low powered, miniature BS is proposed for use in the indoor environment, which is known as Femto BS (FBS). These FBSs are deployed in an ad-hoc manner in order to bring the network closer to the UEs. Therefore, a dense deployment of FBSs is imminent in the near future. The FBSs in close proximity to each other have low Energy Efficiency (EE) and suffer from high inter-cell interference.
Transmit power spreading is a unique concept to improve the EE of a dense FBS network. It is based on the fact that, spreading the transmit power across multiple sub-channels coupled with higher sub-channel reuse results in increased data-rate and decreased energy consumption at an FBS. The spreading factor of an FBS is a scalar quantity that is used to modify the FBS’s transmit power across all sub-channels, while protecting the UEs’ Signal to Interference plus Noise Ratio (SINR) and data-rate. Hence, a dense FBS network’s EE can be maximized, if an optimal set of spreading factors for a dense FBS network is calculated. We explore techniques to find a set of spreading factors that improves the EE of an FBS network.
Fractional Frequency Reuse and Reduced Power Reuse are two major resource allocation techniques to mitigate interference among neighboring FBSs. However, their effectiveness is highly dependent on the location of an UE and the resource allocation profile at the neighboring FBSs. We suggest a procedure to utilize the above two techniques to mitigate interference and maximize resource reuse.