摘要 |
Transmitting device for free-space optical transmission. The invention relates to a transmitting device for transmission through space, using electromagnetic waves of the infrared and/or visible and/or ultraviolet bands produced by one or several discharge lamps. The device is connected by its input terminals ( 1 ) to an a.c. energy distribution system. A mains filter ( 2 ) reduces the conducted electromagnetic disturbances produced by the power circuits comprising a rectifier ( 3 ), a power-factor-correction circuit ( 4 ), a low-voltage power supply ( 5 ) and an inverter ( 8 ). The inverter ( 8 ) is connected to a series inductor ( 9 ) connected in series with a hot-cathode fluorescent lamp ( 10 ) and a capacitor ( 12 ), a parallel capacitor ( 11 ) allowing an optimal start of the lamp. A receiving set for transmission via power distribution lines ( 6 ) delivers "demodulated signals" applied to the control circuitry ( 7 ) which controls the state of the switches of the inverter ( 8 ). The light produced is modulated as a function of the "demodulated signals".
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