Method of using a mobile unit to determine whether to commence handover

A method to determine whether to commence handover, the method comprising a mobile unit:

• receiving a first broadcast channel from a serving base station;
• determining the serving base station received signal code power (RSCPser) based on the first broadcast channel;
• receiving a second broadcast channel from a target base station;
• determining the target base station received signal code power (RSCPtar) based on the second broadcast channel;
• determining if a first cell is a pico cell or a micro cell;
• determining the interference signal code power (ISCPser) of the first cell in which the serving base station operates;
• determining if a second cell is a pico cell or a micro cell;
• determining the interference signal code power (ISCPtar) of the second cell in which the target base station operates;
• determining a first signal code power ratio (RSCPser/ISCPser) for the serving base station by dividing the serving base station received signal code power (RSCPser) by the first cell interference signal code power (ISCPser);
• determining a second signal code power ratio (RSCPtar/ISCPtar) for the target base station by dividing the target base station received signal code power (RSCPtar) by the second cell interference signal code power (ISCPtar);
• comparing the first signal code power ratio with the second signal code power ratio;
• and
• autonomously deciding to commence handover from the serving base station to the target base station, if the value of the first signal code power ratio determined by the mobile unit is less than the value of the second signal code power ratio determined by the mobile unit.