快速CRC逆序校验方法  

Method of fast cyclic redundancy check reverse decoding

作　　者：梁海华[1] 盘丽娜[1] 

机构地区：[1]常熟理工学院计算机科学与工程学院,江苏常熟215500

出　　处：《计算机应用》2013年第7期1833-1835,1865,共4页journal of Computer Applications

基　　金：国家自然科学基金资助项目(61202440)

摘　　要：循环冗余校验(CRC)是计算机网络中常用的冗余校验方法。针对现有的正序(FIFO)校验方法只能对编码寄存器为零初始状态时生成的校验值正确校验的问题,提出一种逆序(LIFO)校验方法。首先,使用状态矩阵对两类串行编码电路进行分析,理论上证明状态矩阵可逆,由逆矩阵变换得出串行逆序校验方法及其电路;通过电路分析,可将串行逆序方法扩展为快速并行逆序方法,无须预补零操作,简化了计算流程。通过实例计算,验证了并行逆序方法能够对任意初始状态生成的校验值正确校验;仿真结果表明该方法具有与并行正序校验方法近似的运算速度。Cyclic Redundancy Check （CRC） has already been used in the field of computer network widely. Since the existing First In First Out （FIFO） method can only decode checksum which is encoded when initial registers state is zero, a Last In First Out （LIFO） method was proposed. First of all, by analyzing two kinds of serial encoding circuit based on transition of state matrix, the authors theoretically proved the matrix was invertible, and serial LIFO method and its circuit could be derived. Depending on serial method, rapid parallel LIFO method was given, in no need of dummy bits, thus simplifying the calculation process. A case study verified the correctness of this method when decoding checksum, no matter what initial registers state was. The simulation results show that FIFO and LIFO have similar calculation speed.

关 键 词：循环冗余校验 先进先出 初始状态 后进先出 运算速度 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]