Cross-layer Approach of Link Adaptation in IEEE 802.16 Broadband Wireless Access Systems
IEEE 802.16 Broadband Wireless Access system (BWA) is a promising emerging technology. In the IEEE 802.16 standard, multiple data transmission rates are defined by employing different modulation and channel coding schemes. How to select a proper mode affects the system performance significantly. In this paper, an efficient link adaptation scheme with QoS support is proposed. The proposed scheme takes both QoS demand and channel condition into consideration to determine a proper transmission mode. The QoS demand of a connection is represented as an expected packet error rate (PER). Based on this expected PER, the BS calculates the required signal-to-noise ratio (SNR) threshold of each mode. By comparing the measured SNR and all modes SNR thresholds, the BS then suggests the SS a proper transmission mode. We evaluate the proposed scheme by simulations. The simulation results show that the link adaptation scheme improves the average system throughput and guarantees each connections QoS demand.
IEEE 802.16 link adaptation PER SNR QoS
Yu-Ting Yu Hsi-Lu Chao
Department of Computer Science National Chiao Tung University
国际会议
上海
英文
2007-09-21（万方平台首次上网日期，不代表论文的发表时间）