Performance improvement for streaming services by link adaptation & power control in EGPRS wireless networks

Using the MPEG-4 Advanced Audio Coder (AAC) music as an example, we investigate the improvement of error performance for the streaming service by link-adaptation and power-control techniques in an Enhanced General Packet Radio Services (EGPRS) cellular network. In particular, we study the effects of a combined link adaptation and power control scheme (referred to as the error-based scheme) for achieving a target error rate, which is non-zero but low enough so that error concealment techniques can be effective. By simulation, we compare the error performance of the error-based scheme at both the EGPRS block and AAC frame level with another adaptation algorithm with a goal of maximizing overall network throughput (referred to as the throughput-based scheme). Our results reveal that when offered with similar traffic load, the former scheme can provide noticeable improvement of music quality over the throughput-based scheme. To achieve similar AAC frame error rate, our results also show that the error-based scheme can increase the link throughput over the throughput-based scheme by 66.7% in one of our examples. These results reveal that link adaptation and power control to achieve required error targets are helpful in improving quality and capacity for streaming data applications.