| 摘要 |
PURPOSE:To obtain a receiver with high secrecy while not being intercepted easily by the 3rd party by providing plural scramble series and applying scrambling to a signal key to descrambling. CONSTITUTION:A reception data is fed to a bit clock extraction circuit 2 from a terminal 1, a bit clock synchronously with a reception data is recovered and fed to a decoder 3, where processing such as error correction is applied. On the other hand, the M series with a prescribed pattern is generated from an M series generating circuit 6 by the instruction from a microcomputer 7 and the M series is fed to a descrambler 5. In this case, a scramble synchronization detecting circuit 9 extracts a data corresponding to the scramble synchronous signal from one frame data to detect whether the said data is coincident with a fixed pattern of the scramble synchronous signal or not. When the circuit 9 detects the scramble synchronous signal, it is know that the reception data is descrambled correctly by the descrambler 5 by the output of the circuit 6. |
