The present invention relates to determining a position of a mobile device, and in particular signaling for on-demand positioning reference signal configuration, for example, in 5G new radio. The present invention provides a positioning device for calculating a position of a mobile device. The positioning device is configured to determine a measurement quality, and/or a reference signal type and configuration based on a positioning request, to determine a reference signal configuration request based on at least the measurement quality, and/or the reference signal type and configuration, to obtain a measurement result based on a reference signal configured according to the reference signal configuration request, and to calculate the position based on at least the measurement result.