Performance Analysis and Study of Orthogonal Multicarrier System with Space-Time Coded Transmit Diversity and Adaptive Modulation over Multipath Rayleigh Fading Channels

• Main Authors: Yuth-Lin Hsieh, 謝育林
• Other Authors: Jeng-Kuang Hwang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/47154829973943572111

碩士 === 元智大學 === 電機工程學系 === 90 === In this thesis, we study and analyze the error performance of the technique of space-time coded transmit diversity and combined it with adaptive modulation in the orthogonal multicarrier system over multipath Rayleigh fading channels. First of all, we assume that our target system is over multipath Rayleigh fading channels, and the guard interval of the transmitted OFDM signal is larger than the maximum path delay spread. Under above assumptions and applying the property of frequency ergodicity, the upper bound error performance of the SISO OFDM/2IMO STC-OFDM system with M-ary QAM is desired and the performance is just equal to that of single carrier systems with the same diversity order over flat fading channels. Furthermore, using Monte-Carlo trials to simulate every channel condition and according it to switch the appropriate modulation level, then a semi-analysis method for calculating the average BER and BPS, i.e. bits per symbol, is also introduced for the OFDM system with adaptive modulation. Finally, computer simulation results will meet the same conclusion of our performance analysis. Besides, using pure Monte-Carlo simulation, comparisons between the performance of multiuser SISO MC-CDMA system and 2ISO STC-MC-CDMA system are also represented.