Scanning the past: George A. Campbell and the electric wave filter
Article Abstract:
George A Campbell was awarded two patents on the electric wave filter in 1917. Campbell was born in 1870 in Hastings, Minnesota, graduated from Massachusetts Institute of Technology in 1891 and received two degrees from Harvard University. Campbell proposed adding coils at specified intervals along a telephone line in order to reduce attenuation and distortion. Campbell's discoveries and inventions led to the use of loading coils for commercial traffic in 1900. The innovation helped AT&T save an estimated one hundred million dollars by 1925. Campbell wrote a memorandum that provided the basis for a patent application in 1913 which did not impress the AT&T patent examiners. Two years later in 1915 the patent's importance was recognized and a patent was filed. Campbell received the Medal of Honor of the Institute of Radio Engineers in 1936 and the Edison Medal of the American Institute of Electrical Engineers in 1940. Campbell died in 1954.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1992
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High speed integrated electronics for communication systems
Article Abstract:
The optical fiber transmission technology, high-speed very-large-scale integration (VLSI) integrated circuit (IC) technology and many of the functional network access components now exist for implementing a revolution in broadband public and private telecommunications networks. The demand for broadband digital services is widespread, and there is a convergence to standards for broadband integrated services digital network (BISDN) services. Components required for accessing and for transmission and routing of traffic on such networks are described. They must perform such activities as synchronous time division multiplexing, asynchronous transfers and switching, circuit switching, line signal conditioning, framing, regeneration, buffering, phase alignment, bit and byte interleaving, and routing. A variety of switches and the future of switching technology are discussed.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1990
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Asynchronous fiber optic local area network using CDMA and optical correlation
Article Abstract:
An experimental fiber-optic LAN is described that uses code division multiple access (CDMA) and fiber-optic delay-line signal processing. CDMA allows many users to access the network concurrently and thereby achieves high throughput with no delay. Throughput-delay characteristics are compared to ALOHA and CSMA-CD.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1987
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