REDUCTION OF INTERFERENCE IN MOBILE TELECOMMUNICATIONS SYSTEMS

A method of reducing interference from neighbouring cells, by optimising transmission Primary Scrambling Codes (PSC) within a small cell of a mobile telecommunications system, comprising: performing a network listening operation in the small cell to monitor transmissions of neighbouring cells, and determining scrambling codes and timing offsets of such transmissions; and providing, either (1) by means of a cross-correlation matrix determined in an initial characterising step, or (2) by means of a real-time cross-correlation process, a Primary Scrambling Code and a timing offset, in dependence on the cross-correlation values of determined codes and timing offsets of the neighbouring cells with codes and offsets that may be used by the small cell, does and offsets for the small cell which have a reduced likelihood of interference with transmissions of the neighbouring cells.