A rate‐based overload control method for the radio channel in PCN

Third‐generation wireless digital communication systems, currently being developed, are intended to integrate all the existing wireless systems and cover a wide range of services, including voice, video and multimedia. A difficult problem towards this direction is the efficient use of the limited available bandwidth. Although considerable improvements have been made recently in transmitter and receiver technology, the capacity of the air interface is still considerably smaller compared to other media such as fiber optics. Accordingly, traffic congestion is an important problem, especially for bandwidth demanding applications (e.g., video), leading to poor quality‐of‐service (QoS). This paper presents an overload control method, for TDMA systems, to temporarily reduce the source rate requirements to a sustainable level, in order to avoid a sudden degradation in QoS. The control is activated when the aggregate rate crosses a predefined threshold that identifies congestion. To ensure fairness, the selection of the sources whose rate will be reduced is performed in co‐operation with a priority‐based scheduling technique. The performance of the system under the proposed method is analyzed and system parameter values are optimized. It is shown that the method attains considerable improvement in the loss probability performance.