1. A method for estimating a channel at a receiver in a wireless communications network, the method comprising: obtaining, at the receiver, channel model parameters for a received signal, based on raw channel estimates for the received signal, each raw channel estimate corresponding to an antenna at the receiver; combining the channel model parameters to generate a first plurality of combined channel model parameters; choosing a first set of indices corresponding to combined channel model parameters from among the first plurality of combined channel model parameters having magnitudes passing a combined channel model parameter threshold; and estimating the channel in a sparse domain based on the first set of indices.