| 摘要 |
PURPOSE:To prevent frame step out by delaying one output of two-system transmission circuits and rearranging their outputs according to a fixed rule and transmitting them and by delaying the output of the other circuit similarly to transmission and rearranging them reversely to transmission in the receiving side. CONSTITUTION:The output of transmission-side carrier-frequency terminal equipment 11 is subjected to bipolar/unipolar conversion and series-parallel conversion in bipolar/unipolar converter 12 to generate two-system PCM pulse trains PCM1 and PCM2. One pulse train PCM2 is delayed by proper number n of bits in a delay circuit to generate pulse train PCM2'. After that, two-system signals are rearranged according to a fixed rule in 14-1 and 14-2 and are transmitted. Meanwhile, in the receiving side, two-system signals are rearranged reversely to the transmission side by 21-1 and 21-2 after the other pulse train is delayed by the same delay quantity as the transmission side in 22. As a result, error bits in the demodulation signal can be dispersed to prevent frame step out. |
