An online calibration algorithm for the CDMA-based adaptive antenna array

We propose a new adaptive calibration algorithm for a CDMA-based antenna array in the presence of unknown gain and phase errors. The algorithm does not require any additional reference signal for calibration and can be applied to both the uplink and downlink. To speed up the convergence rate of the proposed algorithm, we use phase compensated input signals obtained by phase conjugate operation. We verify the algorithm using field data measured through a custom-built W-CDMA test-bed built by SK-telecom.