| 摘要 |
To transmit a plurality of broadband and/or narrowband signals, for example of a plurality of television and sound broadcast programmes, these signals are converted into n non-overlapping frequency bands (FB1 to FBn), which are converted in each case in an electrical-to-optical transducer (W1 to Wn) into optical signals and are transmitted via n parallel optical waveguides (L1 to Ln) from the head station via a plurality of intermediate repeaters to the subscribers (Ü1 to Üj), where the light wavelengths of the optical signals are approximately identical ( lambda 1). At the subscriber end and, where appropriate, in the intermediate repeaters, the n optical signals transmitted in parallel are combined using optical means (K) to form an optical multiplex signal. This signal is converted in a single optical-to-electrical transducer (OE) into an electric multiplex signal. The tuner (comprising a tuning device, IF amplifier and demodulator) of the receiving device converts the desired signal into a baseband signal (video signal or audio-frequency signal). In the intermediate repeater (ZV) of the lowest distribution level, each of the n optical signals is distributed using optical means (K') among j subscribers or transfer points (Ü1 to Üj) (e.g. j = 16). Since the optical multiplex signal passes through a short optical waveguide path only, modal noise is avoided. <IMAGE>
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