The subject system aggregates, or stitches, multiple component channel estimates to generate an aggregated wideband channel estimate that can be used to determine more accurate time of arrival estimations than those determinable from the individual component channel estimates. The subject system also provides for multipath detection on a single channel or an aggregated channel that may be used to facilitate an accurate time of arrival estimation. For example, information derived from the multipath detection may be used to supplement and/or enhance a time of arrival estimation algorithm. The subject system also provides a sounding protocol that allows devices to perform one or more signal exchanges to facilitate generating the aggregated wideband channel estimate and/or to facilitate performing the multipath detection. The protocol allows the devices to perform signal exchanges over one or more channels within a coherence time, and also provides for security mechanisms as well as failure recovery.