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 Forbes ASAP, March 20, 1993 The New Rule of the Wireless At first glance, Vahak Hovnanian, a homebuilding tycoon in New Jersey, would seem an unlikely sort to be chasing rainbows. Yet in the converging realms of computers and communications that we call the telecosm, rainbows are less a matter of hue and weather than they are a metaphor for electromagnetism: the spectrum of wavelengths and frequencies used to build businesses in the Information Age. An Armenian Christian from Iraq, Hovnanian ran a business building high-quality "affordable" housing. His first coup came on Labor Day in 1958 when, together with his three older brothers, he bought an apparently undesirable property near the waterfront in Tom's River for $20,000. From this modest beginning has arisen not only one of the nation's largest homebuilding enterprises (divided among the four immigrant brothers), but also a shattering breakthrough on some seemingly bleak frontiers of the electromagnetic spectrum. Together with maverick inventor Bernard Bossard, Hovnanian has launched a wireless cellular TV business in frequencies once thought usable only in outer space. Perhaps the reason Hovnanian feels comfortable today pioneering on the shores of the telecosm is that some 35 years ago he was an engineer at Philco Semiconductor following in the theoretical steps of AT&T Bell Laboratories titan William Shockley. Shockley led the team that plunged into the microcosm of solid-state physics and invented the transistor. At the heart of all-digital electronics, this invention still reverberates through the world economy and imposes its centrifugal rules of enterprise. This law of the microcosm dictates exponential rises in computer efficiency as transistors become smaller. It is this law that drives the bulk of the world's computations to ever- cheaper machines and pushes intelligence from the center to the fringes of all networks. Today the microcosm is converging with the telecosm and igniting a new series of industrial shocks and surprises. The convergence of microcosm and telecosm in an array of multimedia industries—from personal intelligent communicators to video teleputers to digital films and publishing—is now the driving force of world economic growth. John Sculley, chairman and CEO of Apple Computer, has projected that by 2002 there will be a global business in multimedia totaling some $3.5 trillion—close to the size of the entire U.S. economy in the early 1980s. This new world of computer communications will break down into two domains—the fibersphere and the atmosphere. The fibersphere is the domain of all-optical networks, with both communications power—bandwidth—and error rate improving by factors in the millions. In "Into the Fibersphere" (Forbes ASAP, December 7, 1992), we saw that the potential capacity for communications in the fibersphere is 1,000 times greater than all the currently used frequencies in the air—and so radically error-free that it mandates an entirely new model of wired telecommunications. Now we will discover that the atmosphere will offer links as mobile and ubiquitous as human beings are. It thus will force the creation of an entirely new model of wireless networks. In one sense, Sculley's $3 5 trillion dream can be seen as the pot of gold at the end of Maxwell's rainbow. In 1865, in a visionary coup that the late Richard Feynman said would leave the American Civil War of the same decade as a mere "parochial footnote" by comparison, Scottish physicist James Clerk Maxwell discovered the electromagnetic spectrum. Encompassing nearly all the technologies imagined by Sculley, Maxwell's rainbow reaches from the extremely low frequencies (and gigantic wavelengths) used to communicate with submarines all the way through the frequencies used in radio, television and cellular phones, on up to the frequencies of infrared used in TV remotes and fiber optics, and beyond that to visible and ultraviolet light and X- rays. In a fabulous feat of unification, Maxwell reduced the entire spectrum to just four equations in vector calculus. He showed that all such radiations move at the speed of light—in other words, the wavelength times the frequency equals the speed of light. These equations pulse at the heart of the information economy today. Virtually all electromagnetic radiation can bear information, and the higher the frequencies, the more room they provide for bearing information. As a practical matter, however, communications engineers have aimed low, thronging the frequencies at the bottom of the spectrum, comprising far less than one percent of the total span. The vast expansion of wireless communications forecast by Sculley, however, will require the use of higher frequencies far up Maxwell's rainbow. This means a return to the insights of another great man who walked the halls of Bell Labs in the late 1940s at the same time as future Nobel laureate William Shockley, and who left the world transformed in his wake. In 1948, the same year that Shockley invented the transistor, Claude Shannon invented the information theory that underlies all modern communications. At first encounter, information theory is difficult for nonmathematicians, but computer and telecom executives need focus on only a few key themes. In defining how much information can be sent down a noisy channel, Shannon showed that engineers can choose between narrowband high-powered solutions and broadband low-powered solutions. From Long & Strong to Wide & Weak Assuming that usable bandwidth is scarce and expensive, most wireless engineers have strived to economize on it. Just as you can get your message through in a crowded room by talking louder, you can overcome a noisy channel with more powerful signals. Engineers therefore have pursued a strategy of long and strong: long wavelengths and powerful transmissions with the scarce radio frequencies at the bottom of the spectrum. Economizing on spectrum, scientists created mostly analog systems such as AM radios and televisions. Using every point on the wave to convey information and using high power to overcome noise and extend the range of signals, the long and strong approach seemed hugely more efficient than digital systems requiring complex manipulation of long strings of on-off bits. [ back to top ] | ||
