VHDL硬件描述语言实现M12序列，可以用作白噪声，码率可调-VHDL hardware descr iption language M12 sequence can be used as white noise, adjustable rate

BASYS2 board,FPGA，实现M12序列的生成并加在低频二进制信号上（输入信号），之后实现了位同步提取。-BASYS2 board, FPGA, to achieve M12 sequence generation and added to the low-frequency binary signal (input signal), and then to achieve the bit synchronization extraction.