| 摘要 |
A self-synchronizing transmission loop consists of a transceiver, a transponder, a data link for transmitting a group of eight binary numbers from the transceiver to the transponder, and a data link for transmitting a group of eight binary numbers from the transponder to the transceiver. Each of the transceiver and the transponder uses a bipolar return-to-zero direct-current signal format where each binary number to be transmitted has its own transmission time slot divided into three substantially equal successive time segments T1, T2 and T3. Time segment T1 provides a change from zero level to a single unit level signal of positive polarity (+1) for binary 1 and of negative polarity (-1) for binary 0, time segment T2 provides a reversal of the single unit level signal of time segment T1, and time segment T3 provides a change back to the zero level of signal. During time segment T3 for the last transmission time slot, the change of signal level is of the same polarity as during time segment T1 of that last time slot. After the start of transmission, each transmission by either the transceiver or the transponder of a successive time segment signal level change is initiated only upon receipt from the other of a corresponding time segment signal change.
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