Interference mitigation in an LTE femtocell base station using uplink antenna selection

Antenna selection represents an attractive technique that allows to improve performance of wireless systems due to its simplicity and ease of implementation. Antenna selection is able to provide diversity through the use of multiple antennas while keeping low cost and energy consumption by selecting only a subset of the available elements at any given time, hence requiring a smaller number of RF transmitter and receiver chains. This makes it especially suitable for femtocell or small-cell base stations, typically employed by cellular operators to provide indoor radio coverage in customer premises. This article presents an analysis and validation of antenna selection using a LTE-FDD femtocell prototype. The effects on antenna selection performance of different antenna training schedules and channel variation rates are investigated under realistic propagation conditions. It is observed that antenna selection is able to provide substantial gains in terms of channel quality and reliability in interference-limited scenarios, attesting its suitability for large-scale femtocell deployments.