Users clustering concept: dynamic concentric cells performance in WCDMA system

The paper presents a concept named "users clustering" that consists of first segregating users having commonalities into different clusters and then allocating resources to each of the clusters, either in the frequency, time or code domains. The first operation, grouping the users, is made according to the whole user profile; radio parameters, such as the path loss experienced by the users, as well as some other criteria, independent from the radio link, are taken into account. Such parameters could be the required bit rate, the degree of asymmetry between the uplink and the downlink, the QoS required, etc., or any combination of these parameters. Dynamic features of this technique make it possible to cope with nonuniform user densities and traffic in a radio environment, which is one of the key characteristics of the third generation wireless. Some results are presented comparing clustering architecture with a classical architecture. An enhanced clustering concept is also introduced and evaluated by comparison.