| 摘要 |
PURPOSE:To avoid an erroneous synchronism, by eliminating the same pattern as a scramble pattern or a frame synchronous pattern contained in the reverse signal of the scramble pattern. CONSTITUTION:An AND circuit G8 detects a combination of outputs of flip-flops Q1, Q2, Q3 and Q4 corresponding to the 15th bit in a scramble pattern that changes 0 to 1 to secure a pattern different from a frame synchronous pattern, and then produces 1. Then an OR is obtained for the outputs of AND circuits G7 and G8 through an OR circuit G9. Thus a scramble pattern with a prescribed alteration made on its output is obtained. |
