Adaptive resource allocation in multicast OFDMA transmissions using scalable amortize factor

Recently, dynamic resource allocation for multimedia multicast services has enjoyed tremendous research attention due to its potential to effectively utilize scarce system resources and support demands from multiple users with varying channel characteristics. Different single-rate and multi-rate transmission techniques have been proposed for multicast dynamic resource allocation (MDRA) algorithms to improve the performance of multicast groups. In single-rate technique, most widely used schemes are to skew the multicast group rates to suit the user with least channel gain (LCG) or transmit based on the group average throughput (AVG). However, LCG and AVG cannot provide satisfactory level of fairness and spectral efficiency. In this paper, we show a heuristic algorithm which evidently confirms that we should neither perform single-rate transmissions based on LCG scheme, nor with AVG scheme, but rather we should distribute the high-rate multimedia information over the lower rates using a scalable amortize factor (SAF). Simulation results show that SAF-based single-rate MDRA algorithm is flexible, extensible, offers higher capacity than LCG scheme, and potentially provides rate fairness comparable to AVG scheme.