说明：  实现CRC校验的MATLAB代码，CRC_gen.m用于生成所需传送的信息，输入参数是原始数据D和CRC生成器G，输出参数是传输的数据D+R。CRC_test.m用于测试收到的信息是否能检出1/2/3bit的差错，输入参数为接收到的数据D+R和CRC生成器G。若能检测出所有错误，则没有任何输出，否则会输出不能检出的错误和相应的错误bit位。
(This MATLAB (R2019a) code is used for CRC error detection and CRC code generation. CRC_gen.m is used for generating the additional bits R for error detection, using the CRC generator G and input data D. The output of CRC_gen.m is the combined bits to be sent. CRC_test.m find out if the CRC code may detect all 1/2/3 bits error. If all errors can be detected, the output is nothing. Otherwise, the code will show you the bits that may cause undetectable errors.)