| 发明名称 |
RF MULTIPLE SIGNAL LIGHT TRANSMISSION SYSTEM |
| 摘要 |
PURPOSE:To reduce influence due to the excess modulation of a semiconductor laser and to stabilize the quality of a transmitted image by inverting the polarity of video signals in N/2 channels out of video signals in N channels to be multiplexed to multiplex analog frequency. CONSTITUTION:The polarity of video signals in N/2 channels out of video signals in N channels (N is an integer, 1<N) is inverted to multiplex the analog frequency. Namely the video signals of odd channels are directly inputted to a frequency multiplexing part 2 and the video signals of even channels are inverted at their polarity by analog inverting amplifiers 1 and inputted to the frequency multiplexing part 2 and the analog frequency-multiplexed signal is applied to a light transmitting part 3. In the part 3, a semiconductor laser is modulated by the analog frequency-multiplexed signal and its optical signal is sent to an optical fiber 4. A light receiving part 5 converts the received optical signal into an electric signal and sends the electric signal to a tuner 6 and the video signals of even channels outputted from the tuner 6 are inverted to the original polarity by the amplifiers 1. Thus deterioration in the quality of a transmitted image can be reduced. |
| 申请公布号 |
JPH03132227(A) |
申请公布日期 |
1991.06.05 |
| 申请号 |
JP19890270650 |
申请日期 |
1989.10.18 |
| 申请人 |
MATSUSHITA ELECTRIC IND CO LTD |
发明人 |
NAKADA HIROAKI;TANABE MANABU |
| 分类号 |
H04N7/22;H04B10/00;H04B10/07;H04B10/2507;H04B10/54;H04B10/564;H04B10/58;H04J1/00 |
主分类号 |
H04N7/22 |
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