了解差分编码及译码的电路组成、工作原理和特点；

了解并串，串并变换的电路组成，工作原理和特点；

了解数字频带传输系统的电路组成，工作原理和特点；

了解数字频带传输系统的性能分析方法；

-Understand the difference circuit of coding and decoding of the composition, working principle and characteristics

Understanding and string, string and transform circuit, working principle and characteristics

Composition about digital band transmission system circuit, working principle and characteristics

To understand the performance analysis of digital frequency transmission system