On the performance of eigenbeamformer transmit diversity concept in WCDMA network

We consider the performance of a WCDMA network when an advanced transmit diversity concept called eigenbeamformer is applied. When multiple antennas are used, performance gains are expected. Eigenbeamformer is a closed loop technique where a set of suitable beams is employed. No studies exist for the effects of the technique on system performance in a dynamic environment. This is crucial due to the fact that eigenbeamforming may lead to misdirected beams due to mobility and, as a consequence, might lead to performance losses rather than gains. We present such a study and draw conclusions about the achieved capacity gains/losses. The eigenbeamformer concept works with optimistic assumptions. However, when the effect of errors is taken into account, the process results in performance losses rather than gains.