| 摘要 |
A modulation format for containing, for simultaneously transmitting via a single optical fiber, and for decoding, multiple independent wideband signals. The format derives maximum advantage from the inherent wideband properties of the optical fiber, while utilizing the concept that the signal-to-noise ratio of one channel (e.g., in a red, green, and blue color video signal) is preferably made substantially greater than that for the other two channels. This allows optimizing the signal-to-noise ratio of the signal channels while using a relatively simplified circuit implementation. To this end, the format waveform employs a stationary reference edge and multiple time-variable edges, wherein the time interval between the reference edge and the following time-variable edge of the same polarity always exceeds, or always is less than, one-half of the total available time period of the waveform. That is, the next time-variable edge of the same polarity as the stationary reference edge never crosses the half-way point of the total time period of the waveform in the course of being deviated. The above conditions allow a relatively simplified edge discrimination scheme and demultiplexing circuit.
|
