| 摘要 |
The frequency multiplexed input signal (A) is divided by band pass filters (B1,B2) to produce signals (C,B resp.). The upper frequency band (B) is passed directly to electrical/optical converter (4), which lower frequency band (C) is amplitude modulated by modulator (10) to produce signal (D) which is converted by electrical/optical converter (5). A multiplexer (6) recombines the two signals for transmission. The system divides the signal spectrum into groups of less than one octane, by directly filtering out upper part of signal spectrum and amplitude modulating lower part of signal spectrum. |
