FRAME SYNCHRONIZATION PROTECTION DEVICE

摘要

PURPOSE:To prevent frame mis-synchronization due to an error of a pointer pointing out a frame border position in a packet when frame processing data are sent in a form of the packet. CONSTITUTION:A pointer value separated from a received packet by a packet decomposition means 70 is inputted in a selection means 10, which selects the pointer value or a pointer prediction value outputted from a pointer prediction value arithmetic means 11. The received pointer value is used in the state of out of synchronism including the initial state and the predicted value is used in the synchronizing state. The selected pointer value is used to calculate a succeeding pointer predicted value, and a comparator means 12 compares the predicted value and the received pointer value and number of consecutive coincidence/dissidence is counted by counter means 13, 14. A synchronizing state discrimination means 15 discriminates the synchronizing state based on the count.