Performance analysis of antenna sectorisation in cell breathing

When traffic changes depending upon the behaviour of mobile subscribers, cell coverage range also changes. This phenomenon is known as "cell breathing". We discuss the concepts of cell breathing in a 3rd generation systems environment such as universal mobile telecommunications system (UMTS). A comparison of the system performance is made using results obtained from the simulation of 3 and 6 sectored antennas. In wideband code division multiple access (WCDMA) technology, all users share the same common physical resource, i.e., the frequency band in 5 MHz slices. In the global system for mobile communications (GSM), the capacity calculation is a relatively straight forward procedure, but, in the case of WCDMA, the radio interface is handled differently and the system capacity is limited by various factors. Simulations were carried out to investigate the relationship in UMTS of capacity and coverage. Cells with varying coverage profiles considerably complicate network planning and management. The simulation results show the reduced impact of cell breathing with the use of microcells and multi sectored antennas.