A method executed by means of at least one processor or circuitry comprising: - obtaining or determining a plurality of signal propagation time parameters, wherein each of said plurality of signal propagation time parameters is associated with a respective observation position of a plurality of observation positions (102-1, 102-2, 102-3) of a mobile device and a respective installation position of a plurality of installation positions of a plurality of radio devices (300-1, 300-2, 300-3), and wherein each of said signal propagation time parameters is representative of a respective signal propagation time value of one or more radio signals traveling between said respective observation position and said respective installation position, wherein said plurality of installation positions of said plurality of radio devices (300-1, 300-2, 300-3) comprises at least three installation positions, and wherein said plurality of observation positions (102-1, 102-2, 102-3) of said mobile device comprises at least three observation positions, - determining , for each of said plurality of installation positions of said plurality of radio devices, respective point coordinates of a coordinate system representing said respective installation position of said respective radio device, at least partially based on said plurality of signal propagation time parameters, and - determining motion information associated with said mobile device at least partially based on said plurality of signal propagation time parameters and said point coordinates obtained as a result of said determining, for each of said plurality of installation positions of said plurality of radio devices (300-1, 300-2, 300-3), respective point coordinates. - obtaining or determining a plurality of signal propagation time parameters, wherein each of said plurality of signal propagation time parameters is associated with a respective observation position of a plurality of observation positions (102-1, 102-2, 102-3) of a mobile device and a respective installation position of a plurality of installation positions of a plurality of radio devices (300-1, 300-2, 300-3), and wherein each of said signal propagation time parameters is representative of a respective signal propagation time value of one or more radio signals traveling between said respective observation position and said respective installation position, wherein said plurality of installation positions of said plurality of radio devices (300-1, 300-2, 300-3) comprises at least three installation positions, and wherein said plurality of observation positions (102-1, 102-2, 102-3) of said mobile device comprises at least three observation positions, - determining , for each of said plurality of installation positions of said plurality of radio devices, respective point coordinates of a coordinate system representing said respective installation position of said respective radio device, at least partially based on said plurality of signal propagation time parameters, and - determining motion information associated with said mobile device at least partially based on said plurality of signal propagation time parameters and said point coordinates obtained as a result of said determining, for each of said plurality of installation positions of said plurality of radio devices (300-1, 300-2, 300-3), respective point coordinates. <EOS>