Method comprising: ⋅selecting a subset of one or more beam pairs among a set of beam pairs via which a terminal and a base station are associated, wherein for each of the beam pairs of the subset, a suitability of the respective beam pair is better than a suitability threshold; for each of the beam pairs of the subset: ⋅⋅determining a respective set of at least two tones; ⋅⋅performing a respective relative phase measurement based on the respective virtual wavelength to obtain a respective virtual phase difference; and at least one of ⋅∘reporting the respective set of at least two tones and the respective virtual phase difference to the base station; and ⋅∘estimating a respective distance between the terminal and a transmission reception point of the base station emitting the respective beam pair based on the respective virtual phase difference and the preliminary uncertainty region.