In one aspect, methods and apparatuses disclosed herein improve positioning based on UL signals in a wireless communication network, by sending UL transmission configuration from wireless devices, and by using that information in the network for performing UL-based positioning of the devices. In this regard, the teachings herein advantageously recognize that obtaining UL transmission configuration information from the wireless devices themselves represents a more efficient, complete and richer mechanism for obtaining parameters relevant to configuring and performing UL-based positioning operations. As a further example advantage, the teachings herein provide for control-plane and/or user-plane signaling of UL transmission configuration information, which comprises, for a given wireless device, at least one of resource allocation information for one or more UL transmissions for the wireless device, and UL signal characteristics information.