Asynchronous interference cancellation with an antenna array

The antenna array asynchronous interference cancellation problem is addressed by means of semi-blind algorithms with projections to the finite alphabet. It is observed that the conventional least squares (LS) solution estimated over the training interval may not be suitable for initialization of the iterative semi-blind schemes in the case of asynchronous interference. The simulation results in an OFDM HIPERLAN/2 environment are presented, which demonstrate that, contradictory to the synchronous interference case, a modified LS initialization based on the autocorrelation matrix estimated over the whole burst of data outperforms the conventional LS initialization for high interference levels.