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United States Patent | 5,198,918 |
Freitas ,   et al. | March 30, 1993 |
Methods and apparatus for operating an optical communications system having at least two communicating entities (10,12). In accordance with a method of the invention a first step transmits communication link control information from a first entity to a second entity over a first optical channel having a first data bit rate. Responsive to the transmitted communication link control information, a second step of the method transmits data information from the second entity to the first entity over a second optical channel having a second data bit rate that is greater than the first data bit rate. The first optical channel is preferably a relatively low-bandwidth diffuse transmission infrared radiation channel. The second optical channel is preferably a relatively high-bandwidth infrared channel. One of the entities is a network adapter coupled to a wired network. The network adapter is preferably ceiling mounted. The other entity may be a mobile data processor. A plurality of mobile data processors may be served by one network adapter.
Inventors: | Freitas; Richard F. (Morgan Hill, CA); Harrison; Colin G. (Brookfield, CT); Hortensius; Peter D. (Goldens Bridge, NY) |
Assignee: | International Business Machines Corp. (Armonk, NY) |
Appl. No.: | 605586 |
Filed: | October 29, 1990 |
Intern'l Class: | H04B 010/00; H04B 010/24 |
Field of Search: | 359/113,114,123,124,125,126,135-137,144,152,153,159,161,165,172 370/84 340/825.54 375/8,121 |
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