Patent ID: 7312750

Claim:
A wireless communication system, comprising: an antenna array structure having a plurality of antenna elements that receive and transmit radio-frequency signals; a plurality of radio-frequency units and frequency converters configured to transform received RF signals to receive analog base-band signals and transform analog transmit base-band signals into a transmit RF signals; a plurality analog-to-digital converters configured to convert the receive analog base-band signals into a receive digital base-band signals and a plurality of digital-to-analog converters configured to convert transmit digital base-band signals into transmit analog base-band signals; a multipath delay profile estimation unit configured to estimate delays of multipath signal components based on the receive digital base-band signals; and a plurality of beam-forming units configured to process the multipath signal components, wherein each of the beam-forming units comprises: (a) a set of hierarchical weight banks that store pre-calculated weights in accordance with pre-specified beam look directions, wherein the pre-calculated weights are calculated based on predetermined mathematical models that are independent of signal metrics; and (b) a digital processing unit configured to search for, and operate with, a best beam look direction by: (i) estimating a signal metric from each of the pre-specified beam look directions corresponding to a first level of the hierarchical weight banks; (ii) refining the beam look direction search by iteratively selecting the pre-calculated weights from remaining levels of the hierarchical weight banks that yield a desired quality of the estimated signal metric to obtain the best beam look direction; and (iii) applying the pre-calculated weights that yield the best signal metric to the received digital signal to shift a beam pattern to point to the best beam look direction.