Multipath components of signals transmitted through time-varying digital radio channels are received with individual delays, and signals through a given channel comprise a code identifying that channel. A delay profile indicating a magnitude (Y) for delay values in a search window is calculated repetitively for known channels; the delays of multipath components for known channels estimated; a signal strength indicator calculated; and a search for new multipath components not already estimated performed at regular time intervals. When a new multipath component is found, its identification code is compared to the codes of the known channels. If the code of the new component is identical to the code of a known channel, a delay profile and a signal strength indicator is calculated for a window transposed to include the new multipath component. In this way as many multipath components as possible are included in the search window for a new cell.