发明名称 Communication systems with portable units.
摘要 <p>An optimized full duplex light wave communication system having a base unit and a portable unit. Two continuously operative channels exist between the base and portable units for two way communication at frequencies selected to minimize interference despite the presence of light within the environment of use at both frequencies. In addition, photo emmiters and sensors are specifically configured in an assembly to minimize cross talk between sensors and emitters. A closed loop is formed around the two communication channels that it is operative to regulate the intensity of illumination received at the base photo sensors to a constant level that provides quality audio communications and minimize portable unit battery drain. The closed loop additionally causes base station transmitter frequency tracking of any center frequency variation in the portable unit receiver.</p>
申请公布号 EP0165058(A2) 申请公布日期 1985.12.18
申请号 EP19850304179 申请日期 1985.06.12
申请人 CRIMMINS, JAMES W. 发明人 CRIMMINS, JAMES W.
分类号 H04M1/00;H04B7/26;H04B10/00;H04B10/24;H04M1/73;H04M1/737;(IPC1-7):H04M1/72 主分类号 H04M1/00
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