Telecommunications – Wireless distribution system
Patent
1996-06-28
2000-01-11
Miller, John W.
Telecommunications
Wireless distribution system
324539, 348 6, H04H 100, H01H 3102, H04N 710
Patent
active
060145447
ABSTRACT:
A multiplexed audio-video signal transmission system has a camera-equipped intercom which produces a balanced audio-video signal. A twisted pair-wire connected to the intercom transmits a multiplexed signal of audio signal, video signal modulated to a frequency band not overlapping the audio signal frequency, and DC power. The audio signal and video signal are carried in the pair-wire in opposite phase in a balanced condition, and the DC power is carried between the pair-wire. A relay device is inserted in the pair-wire to refine the video signal. Main line branching device and door branching device are provided to branch out the multiplexed signal to a television equipped control unit 17.
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European Search Report and Annex.
Kubo Seiichi
Shinozaki Noboru
Matsushita Electric - Industrial Co., Ltd.
Miller John W.
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