Techniques are provided for enabling on-demand positioning reference signals (PRS) with a user equipment (UE). An example method for determining a location of a mobile device includes sending a request for downlink positioning reference signals to a network server, where the request includes positioning reference signal configuration information, receiving assistance data based on the positioning reference signal configuration information, measuring one or more downlink positioning reference signals based at least in part on the positioning reference signal configuration information, and determining a location of the mobile device based at least on part on the measurements obtained from the one or more downlink positioning reference signals and the assistance data.