Information Source Coding Combined with Frame Synchronization

前缀同步码是一组固定长度的码字，每个码字由一个公共标志和一个传递输入信息的约束序列串联而成。约束序列满足该条件，使得标记仅出现在相应码字的开始处。因此，即使在可能发生滑页错误的情况下，通过找到标记的位置，我们也可以很容易地恢复码字序列的同步。在本研究中，我们引入了一类具有分布式标记的前缀同步码，其中的符号不一定彼此连续。与相同码字长度的传统前缀同步码相比，提出的部分前缀同步码可以提高码率。推导了基于枚举码的PPS码编译码算法。分布式标记器的构造在给定标记器中固定位数的情况下，我们得到了分布标记器的最大长度，并给出了构造最大分布标记器的方法。符号插入/删除错误纠正前缀同步码推导出能够纠正两个符号插入/删除错误的前缀同步码，如果滑页错误和符号错误不同时发生，所提出的码可以恢复帧同步并纠正符号INS/DEL错误。

1. Derivation of Encoding and Decoding Algorithms on Prefix Synchronized Codes with Distributed MarkersPrefix synchronized code is a set of codewords of a fixed length, each of which is given by concatinating a common marker and a constrained sequence conveying input information. A constrained sequence satisfies the condition such that the marker appears only at the beginning of the corresponding codeword. Therefore, by finding the marker's position we can easily recover the synchronization of a sequence of codewords even if a slip page error might occur.In this research we introduced a new class of prefix synchronized codes having distributed marker in which symbols are not necessarily consecutive to each other. The proposed Partial Prefix Synchronized (PPS) codes can increase coding rate comparing with traditional prefix synchronized codes of the same codeword length. We derived encoding and decoding algorithms of PPS codes based on enumerative coding.2. Construction of Distributed MarkerWe obtained the maximum length of distributed markers given a number of bits having fixed valued in the marker and give a method to construct the maximum dsitributed markers.3. Symbol Insertion/Deletion Error Correcting Prefix Synchronized CodesPrefix Synchronized codes capable of correcting two symbol insertion/deletion errors are derived, The proposed codes can recover frame syncrhonization and correct symbol ins/del errors if slip page error and symbol errors do not occur simultaneously.