Adaptive downlink power control for HSDPA femtocells

Femtocell is emerging as a key technology to improve both the coverage and the capacity in indoor environments, whilst enabling innovative services. Since co-channel deployment of the femtocell network over the existing macrocell one is the most commercially viable solution, a closed/hybrid access policy may lead to severe co-channel interference problems. Therefore, the femtocells have to be carefully operated to disturb as less as possible the macrocell users whilst offering higher throughput to femtocell consumers. In this paper, we propose a dynamic downlink power control mechanism for femtocells, based on the Channel Quality Indicator (CQI) reports. Our results demonstrate that this provide an effective balance between femto users' throughput and femtocell impact on the macrocell performance without modifying the existing back-haul requirements.