Adjacency and channel load of ongoing calls for downlink of multi-rate MC-DS-CDMA to locate vacant code

In this paper, an adjacent maximized channel load (ADCL) assignment scheme is proposed for the downlink of multi-rate MC-DS-CDMA with improved capacity utilization while maintaining the demand of quality of service (QoS). The ADCL scheme assigns new call request to a vacant code which leads to minimum new blocking of higher rate calls. The code selection algorithm first of all selects those codes for which Cl<;Cl
_Threshod
and then there adjacency is calculated, the code with minimum adjacency is selected to handle new call. For a tie, code which leads to minimum blocking of future calls is used to handle new call. Simulation and results shows that, the ADCL scheme provides lesser code blocking probability than other schemes in literature for both type of call arrival distributions quantized and non-quantized.