The present invention relates to prioritizing special cells in
cell selection in a
cellular radio network. In a
cellular radio network one or more cells provide a subscriber with special services or tariffs not offered to all subscribers. These cells are called subscriber's special cells. The
mobile station measures an average reception level and calculates by means of them
cell selection parameters on the basis of which the best
cell is selected. In accordance with the invention, when the
mobile station detects that the cell is one of cells of a special cell
list stored in a memory, it checks first if the cell fulfils a minimum requirement of
cell selection on the basis of the measured
signal level. If the minimum requirement is fulfilled, the
mobile station manipulates the calculation of the
cell selection parameter of a special cell to the effect that the selection probability of a special cell is improved with respect to a
normal cell. In a preferred embodiment of the invention, the manipulation of the calculation comprises a step of adding a predetermined margin to the measured
signal level of a special cell before the
cell selection parameter is calculated. This will minimize the possibility that the mobile
station would accidentally be camped on a
normal cell when it is within the area of a special cell.