A method for assigning scrambling codes in a code division multiple access cellular radio communications network includes a plurality of network cells covering a geographic area, including: determining, for each of the cells, a respective set of adjacent cells by: taking a first set of cells that are neighbors of the given cell; taking a second set of cells that are neighbors of neighbors of the given cell; taking a third set of cells that are neighbors of neighbors of neighbors of the given cell, wherein two cells are considered neighbors in case the respective coverage areas at least partially overlap; taking a fourth set of cells which, in at least one point of the best server are of the given cell, have an adjacent coefficient with the given cell higher than a predetermined threshold; combining the first, second, third and fourth set of cells; and assigning to each cell of the set of adjacent cells a scrambling code different from a scrambling code assigned to the given cell.