| In this thesis, we propose a basic priority and fairness (BPF) and a modified priority and fairness (MPF) based packet scheduling algorithms for adaptive modulation and coding (AMC) scheme based orthogonal frequency division multiple access (OFDMA) wireless communication systems supporting both real time (RT) and non-real time (NRT) traffics. In the AMC based OFDMA systems considered in this thesis, multiple access is achieved by assigning subchannels, each of which consists of a set of subcarriers, to individual users, and the modulation and coding scheme on each subchannel is determined adaptively according to the time-varying channel conditions. In the proposed packet scheduling algorithms, various traffics are transmitted in a sequence determined by their priorities on each subchannel, jointly considering the fairness among users and subchannels. Simulation results show that the proposed algorithms are able to satisfy various quality of service (QoS) requirements, like packet loss rate, delay, or throughput, for a variety of RT and NRT traffics such as voice, video, WWW and email. Also, the proposed BPF and MPF packet scheduling algorithms can support more users than some existing packet scheduling algorithms under the same QoS requirements.Index Terms---Orthogonal frequency division multiple access (OFDMA), Orthogonal frequency division multiplexing (OFDM), adaptive modulation and coding (AMC), packet scheduling, quality of service (QoS). |
