|Title||:||Efficient User Association and Interference Mitigation in Heterogeneous Cellular Networks|
|Speaker||:||Sudeepta Mishra (IITM)|
|Details||:||Tue, 5 May, 2015 2:00 PM @ BSB 361|
|Abstract:||:||A Heterogeneous Cellular Network (HetNet) consists of a set of low power Base Stations (BSs) deployed in the conventional Macro BS (MBS) coverage area. These low powered BSs provide benefits such as, improved system throughput, higher spectral reuse, and energy efficiency. However, due to the disparity in transmit power among these low powered BSs, HetNet suffers from lower small cell utilization and higher interference at edge User Equipments (UEs). These challenges reduce the anticipated improvement from the low powered BSs.
Cell biasing is a technique which can be used to deal with low small cell utilization. It uses a scalar value to artificially modify the signal strength received at UEs from the low powered BSs. This artificial modification in the signal strength changes the UE association, which in turn improves cell utilization. Hence, offloading an appropriate number of UEs from highly loaded BSs to lightly loaded BSs is crucial to achieve good cell utilization and reduce UE blocking. We explore techniques to obtain an optimal bias value to increase small cell utilization.
Almost Blank Sub-frame (ABS) is a technique in which MBS abstains from transmission on some sub-frames, thereby mitigating the problem of higher edge UE interference. Moreover, it also plays a significant role in lowering the system blocking. We explore techniques to obtain the best possible ABS density that can minimize the system blocking.