Efficient radio resource allocation for real-time video with QoS assurance

Real-time video applications over wireless internet have been increasingly deployed with the development of the third generation (3G) and beyond wireless networks. Transmitting real-time video is intrinsically challenging because of the complicated video traffic pattern, large bandwidth requirement, scarce spectrum resource, and wireless erroneous channels. While the technology of 3G and beyond wireless networks is providing fairly large bandwidth, the demand driven by impending applications makes the wireless link the bottleneck of the integrated wired/wireless networks. Thus, efficient utilization for wireless media is a critical issue in radio resource management. For real-time videos, correct and timely delivery of content over the erroneous wireless channel in a packet switching network can be achieved by quality of service (QoS) provisioning in terms of packet loss rate (PER) at the network layer and bit error rate (BER) at the physical layer due to delay and channel errors. Forward error control (FEC) and automatic retransmission request (ARQ) can be used to improve the transmission reliability. The task of radio resource management is to satisfy the QoS requirement per user and at the same time accommodate more users in the network to achieve higher spectrum utilization.; In this thesis, we investigate the efficient transmission of the real-time video stream with QoS assurance over the wireless channel. Firstly, we consider the wideband code division multiple access (W-CDMA) system and propose an efficient scheduling scheme for real-time videos with Markovian property. An analytical approach is derived to evaluate the QoS performance when delivering the real-time video over erroneous channels. Secondly we investigate in a more general wireless fading environment with adaptive FEC how to efficiently transmit multi-layered videos. Adaptive transmission schemes are proposed for the layered video to accommodate the channel variation. Integrated and differentiated QoS provisions are discussed to the different QoS requirements of the basic layer (BL) and enhanced lavers (ELs). Compared with the conventional effective capacity (EC) approach, the proposed schemes significantly improve the channel utilization. With the fast evolution of wireless networks, orthogonal frequency division multiple (OFDM) access becomes the primary air interface for IEEE 802.16 standard and future fourth generation wireless networks. Thus, thirdly, based on the ample flexibility of OFDM technology, we further propose rate allocation schemes for multi-layered and variable rate videos to effectively optimize the spectral efficiency with per user QoS satisfaction. Last, since user mobility information is important to radio resource management, a location estimation algorithm based on Self-Organizing Flap (SOM) is proposed for various non-line-of-sight (NLOS) terrestrial situations to improve the estimation reliability.