Development of IEEE 802.11n WLAN cross-layer simulator using systemC with rate adaptation algorithm for aggregated frame

Abstract

A lot of researches and development has been performed in order to increase the performance and MAC layer and PHY layer of IEEE 802.11 WLAN system. However, most researches and literature focus on the partial area of each layer. In other words, higher layer researchers assume the lower layer’s performances, and lower layer designers do not care much in general. For example, adopting the multiple-input multiple-output MIMO technology, a lot of modulation and coding rate (MCS) combination with the number of using antennas arises. As a result, the algorithm for selecting the MCS considering the channel condition such as signal to noise ratio becomes critical to the system performance of MIMO WLAN system. MCS Selecting, so call rate adaptation algorithm. This is the reason that the cross-layer simulator is required in order to examine the overall system performance which is depend on the many parameters from different layers. In this dissertation, IEEE 802.11n cross-layer simulator based on SystemC is developed. It contains real operational function blocks of physical layer and MAC layer with various rate adaptation algorithms. An application guide-line to apply rate adaptation to IEEE 802.11n MIMO system is outlined in this thesis. The conventional statistics based rate adaptation algorithms have been extended for application to 802.11n and their performances are compared and analyzed. A novel LQM based RA algorithm is proposed. And statistic based rate adaptation for the aggregated frame is proposed. The conventional statistic RA algorithms consider single MPDU only. So, it is hard to apply statistic based RA to multiple MPDU transmissions such as aggregation. Based on this scheme, 12Mbps and 2Mbps of goodput incre-ment is achieved when compared against RRAA and ARF, respectively. Finally, a novel algorithm for selecting MCS and the number of MPDU aggregation for A-MPDU simultaneously is proposed. The simulation result shows the effectiveness of the proposed al...