Study and Implementation of 16QAM Modulation and Demodulation

• Main Authors: Jie-Long Lin, 林杰龍
• Other Authors: Szu-Lin Su
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/04277733037846600257

碩士 === 國立成功大學 === 電機工程學系 === 89 === The need for efficient utilization of an available spectrum has led to employ the highly spectrum-efficient modulation techniques. For this reason, we choose the 16-state quadrature amplitude modulation (16QAM) to implement. In the band-limited channel, the phenomenon ISI will cause signals to influence each other. So we use the equalizer to reduce the effect of ISI. Here, we choose a five-tap complex LMS equalizer. In order to increase the convergent rate of the equalizer, we do the channel estimator to get coefficients of the equalizer. Besides the carrier recovery, clock recovery, differential coding and filters are needed for the system. The 16QAM modem is implemented by the processor TMS320C6211DSK. The baud rate is 2.4kHz with 9.6kHz bps and the carrier frequency is 1.8kHz.