A dynamic channel assignment algorithm for voice and data integrated TDMA mobile radio

Abstract

It is highly desirable to develop an efficient and flexible dynamic channel assignment algorithm in order to realize an integrated traffic TDMA mobile radio communication network. In this paper, an integrated traffic TDMA system is studied in which transmission of voice and data are assumed to occupy one and n time slots in each TDMA frame, respectively. In general, two types of channel (time slot) assignment algorithms are used: the partitioning algorithm and the sharing algorithm. However, they are not well-suited to the multimedia traffic consisting of various information sources that occupy different number of slots per frame. In this paper, assuming that voice is much more sensitive to transmission delay than data, an algorithm based on the sharing algorithm with flexible time slot management scheme is proposed as follows. To reduce the blocking and forced termination probabilities of a voice call, part of the slots of data calls are transferable to voice calls during congestion periods. At the same time, to reduce the handoff-failure of a multi-slot data call, the required number of data slots can be reduced adaptively according to the available number of slots during its handoff. These data calls whose number of slots are reduced either for voice calls or its handoff are allowed to get restored when possible. Computer simulations confirm the good performance of the proposed algorithm when compared to conventional channel assignment algorithms.