Frontiers of Engineering Reports on Leading-Edge Engineering from the 2002 NAE Symposium on Frontiers of Engineering (2003) / Chapter Skim
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Dinner Speech
Dinner Speech
Pages 109-118
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From page 111... ...
Digital satellite broadcasting and wireless cellular voice and data transmissions are the beneficiaries of this half-century of remarkable progress. INTRODUCTION A crude form of digital communication began at the turn of the twentieth century with Guglielmo Marconi's experiments.
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From page 112... ...
William Shockley left Bell Laboratories to found Shockley Laboratories, which lost its key researchers to Fairchild Corporation, from which emerged the founders of Intel Corporation, the prime mover in the creation of the personal computer through the development of the microprocessor. In fact, in 1965, Intel's cofounder Gordon Moore foresaw the exponential growth in solid-state integration and predicted that device density (the number of devices per silicon integrated circuit)
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From page 113... ...
Rice's work at Bell Laboratories, which was published in 1944 in a paper in the Bell System Technical Journal entitled "Mathematical Theory of Noise," applied random-process theory to the communication problem. In 1948, his colleague Claude Shannon, who had spent the war years theorizing on cryptographic concepts, published papers in two issues of the same journal entitled "A Mathematical Theory of Communication," which introduced startling new concepts that went well beyond any previously well established theory.
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From page 114... ...
But the requirements of digital communication processors go beyond the processing speed and memory requirements of a computation processor. Best described as real-time digital-signal processing, it includes the basic operations of Fourier transforms and statistical operations, such as likelihood function computations involved in demodulation and decoding.
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From page 115... ...
Conceived as the ARPANET in the late 1960s for sharing programs, processing capabilities, and databanks among a few dozen laboratories and universities working on defense research, the Internet now connects countless nodes and services hundreds of millions of users through the Worldwide Web. The most recent and most widespread digital communication application, cellular wireless telephony, now serves more than one billion subscribers, onesixth of the world population.
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From page 116... ...
and entered service in the mid-199Os. South Korea adopted CDMA as its sole digital standard, began service in 1996, and was remarkably successful, not only in penetrating more than half of the population but also in converting the nation from an importer of technology to a major exporter of technology.
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From page 117... ...
The principal difference between the two 3G versions, CDMA 2000 and WCDMA, is that the former is a direct evolution of the 2G version CDMA One and therefore requires synchronization of the (base station) infrastructure; the latter, WCDMA, puts the burden on subscriber handsets through increased processing and consequently higher power consumption.
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From page 118... ...
118 ANDREW J VITERBI · For the same reason, the downloading of Web pages to PCs or PDAs away from one's office or home is also more attractive.
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