A SPREAD-SPECTRUM BASED CELLULAR MOBILE RADIO SYSTEM, AND A CONTROL ARRANGEMENT, A RADIO BASE STATION, AND A MOBILE RADIO STATION

摘要

Known are spread-spectrum based cellular mobile radio systems (1). Due to interference from calls in neighbouring radio zones (j') with respect to given radio zones (j), too much traffic per radio zone (Z1, Z2) could easily lead to system overload to the effect that the quality of calls becomes unacceptable. It is proposed to overcome this problem by resolving average mutual interferences (Iu(j)av, Id(j)av) between radio zones (j, j') from a total interference experienced in a radio zone (j), using statistical methods. First, interference measurements are carried out in the radio zones (Z1, Z2), and data is transmitted to a central control arrangement (CA) which resolves the average mutual interferences. Then, these average mutual interferences (Iu(j)av, Id(j)av) are used in an optimization process for acquiring access control parameters (x) for controlling traffic per radio zone (Z1, Z2). In the optimizing process various objective functions may be applied so as to fulfil system operator demands. Thus, system overload is avoided, and further, a flexible tool is provided for satisfying operator demands.