通过实验统计发现，测试向量中与参考数据块相容的数据块数量越多，其在测试数据中出现的频率就会越 小，反之，则出现的概率会越大。根据此规律，本文提出了一种利用FDR 码变体来对测试数据进行压缩处理的算法。通过对 ISCAS 基准电路进行仿真实验，证明该算法比其它编码方式更能提高压缩率。

Experiment statistic finds that the more number of data blocks of test vectors are compatible with the reference data blocks, the smaller frequency of occurrence in the test data will be. On the contrary, the greater frequency will appear. According to this law, this paper presents a test data compression algorithm with FDR code. The simulation experiment of ISCAS reference circuit shows that the algorithm is better than another encoding mode in improving the compression ratio