Reducing Wastage Capacity in OVSF Based CDMA Networks Using Dynamic Rake Combiners
Orthogonal Variable Spreading Factor (OVSF) codes in CDMA networks are designed to handle quantized data rates. Handling non-quantized data rates in such networks leads to code capacity wastage if traditional single code assignment is used. Although, the use of multiple codes reduce this wastage capacity but the use of large number of fixed rake combiners per call increase cost and complexity of the system. The author propose zero wastage designs in which the rake combiner's usage is made dynamic and the amount of rake combiners used depend upon the rate type, with more combiners given to the rate which deviates significantly from the quantized one.