DTV receivers using an adaptive switched beamformer with an online-calibration algorithm

We propose DTV receivers using an adaptive switched beamformer with an online calibration algorithm in the presence of unknown gain and phase errors of an antenna array. The proposed calibration algorithm is based on the subspace method which does not require a prior knowledge of the angle of arrivals (AOAs) of the multipath signals. The calibration algorithm provides us with the estimates of the AOAs of multipaths as well as calibration information of the antenna gain and phase. By utilizing the AOA estimates, an adaptive switched beamformer which has lower hardware complexity than the conventional switched beamformer is developed. To demonstrate our proposed scheme, we develop a complete DTV beamforming receiver, equipped with the proposed calibrator, synchronizer, and equalizer, which is compatible with a wide variety of commercially available VSB demodulator chips.