A novel adaptive modulation scheme in cooperative communication systems

• Main Authors: Han-Sheng Ho, 何翰昇
• Other Authors: Hon-Son Don
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/43005391114347218621

碩士 === 國立中興大學 === 電機工程學系所 === 99 === Cooperative communication has became popular research recently. Since the mobile users can help sending the information each other in cooperative communication system, it can achieve cooperative diversity similar to the multiple-input multiple output (MIMO) system and overcome some limitation of MIMO systems. Furthermore, the cooperative communication with adaptive modulation (AM) can improve the system performance. The adaptive modulation can increase the data throughput and satisfy the required error rate. In general, we use thresholds to decide the transmission rate. However, the fixed thresholds cause ine ciency of the system performance. Therefore, a novel adaptive modulation method is proposed in this thesis. We can improve the performance intensely by changing the thresholds and modulation scheme of each average signal to noise rate (SNR). This method can be compared to fixed thresholds and verify that our proposed method is better than fixed threshold. We also compare our method to optimum thresholds and the results prove complexity of our proposed method is lower than optimum thresholds.