【摘要】 对ADSL中采用的两种调制技术DMT和CAP/QAM进行了对比 ,在此基础上提出了采用QAM调制的ADSL实现方案 .该方案以CPLD芯片为核心 ,用大规模CPLD芯片完成ADSL所必需的主要数字信号处理工作 .已完成了ADSL发送器模块的设计部分 ,包括USB接口、专用数字信号处理器和模拟前端更多还原

【Abstract】 The contrast and the analysis of the key technologies DMT and CAP/QAM in ADSL are given and a design of ADSL modem adopting QAM modulation is presented. This design is based on a large scale CPLD chip that performs all the digital signals processing needed in ADSL modem. The transporting module in this design is implemented including the USB interface, the CPLD based DSP and the analog front end.更多还原