A subrating channel assignment scheme for cellular radio network with directed retry

In this paper the subrating channel assignment scheme is used to improve the performance of handoff packets. The subrating of a channel is done by dividing temporarily a full-rate channel into two half rate channels. Hand-off voice calls may also be served by subrated channels if all channels of the BS are occupied. The subrating of channels can degrade the quality, but it improves the grade of service (GOS) for hand-off calls and minimizes the delay. The provision of directed retry in overlapping area among neighbouring cells is also done for handoff attempts so that the blocking of handoff traffic can be checked to some extent. By using an iterative algorithm we obtain performance indices such as blocking probabilities, degradation in quality, total carried load, dwell time, etc. Numerical results have also been facilitated to prove the validity of the proposed iterative algorithm.