QoS-oriented scheduling algorithm for mobile multimedia in OFDM

In this paper, we propose and evaluate a new algorithm to schedule multimedia data in a multi-user OFDM wireless system. This algorithm dynamically allocates the resource in both time and frequency domains based on feedback channel states, packet QoS requirements and the amount of data to be transmitted. Accordingly, maximum delay, BER requirement and priority of the packet are well met with improved system throughput, even with harsh channel conditions. Moreover, several neighboring subcarriers may grouped together, while possibly incorporating with an adaptive coding & modulation, to deliver multiple data rates depending on actual channel state information. Performance assessment has been conducted per a channel model with Doppler shift, multi-path fading and path-loss. It is shown that the proposed algorithm is quite effective to guarantee QoS for high rate multimedia transmission in OFDM systems.