System architecture and cross-layer optimization of video broadcast over WiMAX

Video broadcast and mobile TV have received significant interests from both academia and industry recently. The emerging mobile WiMAX (802.16e) is capable of providing high data rate and flexible quality of service (QoS) mechanisms, making the support of mobile TV very attractive. However, how to efficiently deliver video broadcast over WiMAX is not straightforward, especially in the multi-BS mode. The multi-BS mode requires multiple BSs to be synchronized in the transmission of common multicast/broadcast data. In this paper, we first identify the key design issues for video broadcast over WiMAX in the multi-BS mode. Then, we present an end-to-end solution which fully addresses key issues such as synchronization, energy efficiency and robust video quality. Moreover, we propose a methodology to optimize the coverage, the spectrum efficiency and the video quality. Results show that our proposed scheme can significantly improve the coverage and spectrum efficiency while satisfying video quality requirements.