| 摘要 |
PROBLEM TO BE SOLVED: To provide a douplex AAL1 converter, capable of reducing a cost and reducing a software processing load by simplifying a circuit scale, device constitution and software processing required for synchronization, when switching a system without cell damages. SOLUTION: In the state of synchronizing a cell leading phase with the ATM-side interface of a douplex synchronization AAL1SAR function 4 as reference 8 kHzFP, an AAL1 cell payload read control part 42, an AAL1 header giving part 43 and an ATM header giving part 44 generate a fixed number of cells within an 1FP time. By performing a specific VC cell disposal in a specific VC cell disposing part 45, the phase relation of respective VC cells from the 47FP leading of an AAL1 cell existing in a 47FP frequency signal is fixed. When its own system is at stand by and in the case of synchronizing operation instruction, a synchronization cross control part 47×8 frame counter 47 performs subordinate synchronization by using the signal of each 376FP from the AAL1 cell conversion part as a reset signal. |
