Blind Recognition of Linear Block Codes Based on Ordered Gaussian Elimination

To address the issues of poor fault tolerance and high computational complexity in traditional matrix analysis methods for identifying the code length and synchronization of linear block codes, an improved identification method based on ordered Gaussian elimination was proposed. The algorithm first constructed a codeword matrix from the intercepted bit stream and divided it into a set of continuously overlapping submatrices. Ordered Gaussian elimination was then applied to solve for potential check vectors, and check vectors were selected using a threshold decision, while relevant statistical measures were calculated. Finally, the code length and synchronous position were identified based on the distribution patterns of these statistical measures. Simulation results demonstrated that, compared to existing methods, the proposed algorithm significantly reduced complexity by avoiding redundant calculations and further improved fault tolerance by optimizing decision criteria, exhibiting stronger robustness in high bit error rate environments.