摘要 |
Bidirectional, non-interfering transmission of broadband services on a single fiber is accomplished by simultaneously combining wavelength-division, time-division, and subcarrier multiplexing on the downstream and upstream transmissions. High speed electrical data signals are time-division multiplexed at the exchange into a composite signal which modulates a standard diode laser operating at a first wavelength. Data signals from an individual subscriber are modulated onto a subcarrier designated solely for the particular subscriber which, in turn, modulates a laser operating at a second wavelength. Extraction and insertion of the upstream and downstream transmissions at the subscriber and exchange locations is accomplished with wavelength selective couplers.
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