A study on adaptive real time video over LTE

LTE, The next generation mobile network system by 3GPP, only allows IP-based transport. Traditional telephony services such as voice and video real-time communication will be provided through the use of IMS (IP Multimedia Subsystem) Multimedia Telephony (MTSI) which imposes high demands on the transport channel. In a packet switched network any intermediary node can act like a congestion bottle neck leading to delay or packet loss. In this scenario a fast end to end adaptation scheme at the media layer can play a vital role to secure service performance by ensuring high quality throughout the session, even in extreme conditions, and keeps the service alive avoiding session termination. This thesis report describes a study of perceived video quality improvement using end to end congestion control depending on both “pre-warning” for congestion and packet loss observed at receiver in IMS video telephony over 3GPP LTE system according to 3GPP TS 26.114 V7.0.0. In the process of achieving the goal a new adaptation state machine was developed with different strategies to address the early congestion notification and packet losses. Simulations has been carried out with different adaptation schemes to compare results and benefits of newly proposed scheme. This thesis shows the effectiveness of early congestion notification for real-time video transmission and reveals some important aspects of adaptation procedure which need to be considered while designing adaptation for video traffic to avoid the congestion in a LTE network. The results found in the study suggest the inclusion of ECN for UDP traffic for future network like LTE.Validerat; 20101217 (root