It used to be the first thing you'd see in the Sunday funnies: the square-jawed visage of Dick Tracy, speaking into a "two-way wrist radio." The fictional detective has become a cliché in the new age of high-tech communications. In fact, many observers proclaim that the technology of cellular mobile radio telephones will make the widespread availability of two-way wrist radios a reality. And ITT even used Dick Tracy's image to advertise new telecommunications developments.
This symbol might have more relevance to the cellular age than is commonly thought. The technology promises to make widely available pocket- or wristwatch-size telephones—current cellular phones are slightly bigger than ordinary ones—but it also may make possible special uses by the police. Cellular telephones could conceivably become one of the new law-enforcement tools of the '80s and beyond.
This possibility raises disturbing questions about citizens' constitutional right to privacy and their ability to protect that right. Given the fast pace of technological change and the comparatively slow pace of legal change, technology promises to outstrip the law. How, then, can individual privacy survive the threat of growing government intrusion in the new communications age? The question is vitally important for a free society. The most promising immediate answer lies not only in the courts and the legislatures but in another essential institution of a free society: the marketplace. Communications firms will help privacy survive the new communications age, if they realize that to attract and keep customers they must implement and improve ways to safeguard confidential customer information.
In his 1983 keynote speech inaugurating Washington, D.C.'s cellular system, John Naisbitt, author of the bestseller Megatrends, suggested how cellular technology will change the way people think about communications. "People will be connected as individuals regardless of where they happen to be physically located at any one time," he said. "We'll be able to [reach out and touch someone] anywhere, anytime, with our portable telephone." Offering an encouraging view of the future of individual autonomy, Naisbitt speculated that the revolution in personal communications may one day allow individuals to bypass national telecommunications systems. "The implications for totalitarian countries," he proclaimed, "are just staggering."
But this growing capacity for individual contact also portends cellular's potential use as a surveillance tool—the dark side of the new communications age. When nearly all individuals become part of a personal-communications network more extensive than today's phone system, the authorities may be able to "reach out and touch" them—whether or not an individual wants (or knows about) the contact. In other words, this brave new world of instant communication may erode the notion of privacy—and our ability to protect it. This is particularly a threat with cellular technology, because it may supply the means to pinpoint the locations of all system subscribers (see sidebar, page 26). The problem is magnified where such advances eclipse existing legal protections.
Technological developments historically have affected the scope of individual rights. When it comes to the right of privacy, science has provided new ways to intrude on individual lives, while the law protects primarily against past abuses. Thus, difficulties arise when science creates a world that is significantly different from the law's view of reality.
Introduction of the telephone, for example, led to a disparity between legal change and technological development. When first confronted with the issue of whether or not wiretapping telephone conversations constituted an unreasonable search, the Supreme Court ruled that official eavesdropping was permissible. This decision, in the case of Olmstead v. United States, came in 1928 as the telephone was becoming a household necessity, but it applied legal concepts developed in the 18th century.
The Constitution's framers intended the Fourth Amendment as a restraint against unreasonable search and seizure to protect individuals from government interference with their property, especially personal papers. When the amendment was adopted in 1791, it was sufficient to protect the privacy of communications, since correspondence was conducted in tangible form. But when the telephone made personal communication intangible, the law did not keep up. In Olmstead, the court merely applied its time-honored understanding of property rights: "The [Fourth] Amendment does not forbid what was done here," the court ruled. "There was no searching. There was no seizure. The evidence was secured by the sense of hearing and that only. There was no entry of the houses or offices of the defendants."
Justice Louis Brandeis, writing in dissent, was more sensitive to the effect of technological development on civil liberties. He pointed out that discovery and invention have given government means "far more effective than stretching upon the rack" to extract information from defendants. "The progress of science in furnishing the Government with means of espionage is not likely to stop with wire-tappings," he added. "Ways may some day be developed by which the Government, without removing papers from secret drawers, can reproduce them in court."
Justice Brandeis's concern with the widespread use of government espionage was well-founded. In the years following Olmstead, electronic surveillance was widely used, posing an ever-increasing threat to civil liberties. Justice William Brennan pointed out in 1963 that "our decisions…[have] been outflanked by the technological advances of the very recent past." And Justice William O. Douglas warned three years later that "we are rapidly entering the age of no privacy, where everyone is open to surveillance at all times."
This concern reached new heights in 1975 as Congress considered advances in surveillance technology and data banks. During hearings on the issue, former US Sen. John Tunney (D–Calif.) worried that "technological developments are arriving so rapidly…that we are in danger of losing the capacity of shaping our own destiny.…This danger is particularly ominous when the new technology of surveillance conveys effective control over our privacy, our freedom and our dignity."
Forty years after Olmstead, the Supreme Court finally caught up with the development of the telephone. It concluded that technology had indeed progressed such that a new Fourth Amendment theory was needed. In the 1967 case of Katz v. United States, the court overturned Olmstead, holding that wiretapping constitutes an unreasonable search. In Katz, the court even extended Fourth Amendment protection beyond the individual's home to include conversations from a public telephone booth. According to this new formulation, the Fourth Amendment protects "people, not places." Where the individual has exhibited a "reasonable expectation of privacy," the law must protect that privacy.
Although the Supreme Court belatedly came to terms with the existence of telephones, technology marches on, and new inventions again and again pose potential civil-liberties problems.
For example, interactive "two-way" cable television—by which subscribers can send and receive signals over their TV sets (to tap into a data bank, for instance, or to pay bills)—raises a number of privacy issues. Former Federal Communications Commission (FCC) chairman Charles Ferris has pointed out that interactive-cable operators will have composite files on their subscribers that could contain such information as the way in which consumers pay their bills and what they purchase; the consumers' programming preferences; and, if the system is hooked into the home security system, when the consumer returned home the previous night. "In other words," Ferris concluded, "it will know more about them than anyone should." The comprehensive nature of such files raises the possibility of significant privacy invasions by both government and private interests. This brings to life Justice Brandeis's warning that searches may one day be conducted without anyone ever entering the home.
Already, police have used video technology for surveillance purposes. Federal investigators have placed hidden video cameras in the residence of suspected terrorists to gather information, and this exceedingly intrusive surveillance practice has been approved judicially. Also, closed-circuit-television (CCTV) surveillance systems have been employed to continuously monitor city streets and, as in the nation's capital, subway platforms. The now-defunct federal Law Enforcement Assistance Administration funded CCTV systems in a dozen cities in the 1960s and '70s as part of its aid to states to beef up the criminal-justice system. Such monitoring systems, of course, have long been commonplace in the private sector, in institutions such as banks. But when the government engages in around-the-clock video surveillance of city streets, serious constitutional issues are raised.
Another means of electronic surveillance currently in vogue among police departments is the use of electronic tracking devices. One method involves attaching a radio transmitter, or "bumper beeper," to a suspect's possessions—on a car, for instance, or a briefcase—and using a receiver to follow the "trail." Police don't need a court order to use the beepers.
Several firms, including Geostar Corporation, have filed applications to operate a system of satellite tracking devices, and the Federal Communications Commission has taken preliminary steps to approve the applications. With its system, Geostar claims, "everyone in the U.S. could be located instantly" through the use of a small, hand-held transmitter and three satellites. Using a computer link, the satellite system could fix the location of the transmitter's signal by latitude, longitude, and altitude. In tests, the proposed equipment was accurate within seven meters.
Though initially proposed for industrial and emergency uses, the satellite locator system also would vastly expand the ability of the police to tail suspects. Indeed, FCC officials have applauded the system's potential capability to alert police to "the event and location of crimes." Although this particular portrayal paints the scenario of an embattled crime victim signaling for help, the same technology could be used for intrusive surveillance purposes.
As these brief examples suggest, technological change has serious ramifications for the future of civil liberties—especially privacy. And the trend is hastened by the combination of computer and communications technology. "Shifts in technology somehow move activities in and out of the law's protection," says Fred Weingarten, program manager for communication and information technologies at the Congressional Office of Technology Assessment. "More and more of what we do is not covered by our traditional protections." And at an American Bar Association symposium on technology and freedom last year, one panelist similarly cautioned that "unless we strengthen the laws protecting our privacy, the right to that privacy will vanish."
Just as wiretapping made obsolete a Fourth Amendment theory based solely on property rights, new computer and communications technologies promise to vitiate Fourth Amendment theory predicated upon a "reasonable expectation of privacy." A 1979 survey by Sentry Insurance Company, for example, found that 54 percent of the respondents considered the existing use of computers a threat to personal privacy. With new applications of the technology, that percentage has increased. According to a 1983 Harris poll, two-thirds of Americans feel that information is being collected on them without their knowledge. Most respondents agreed that it was "possible" or "likely" that the government would use this data to intimidate individuals and reduce their privacy.
Given these attitudes, one may well wonder whether the nation will soon reach a stage at which any expectation of privacy is considered unreasonable. And if nobody expects privacy, will the law continue to protect it? In this context, cellular telephones may further reduce individuals' expectations of privacy. By combining communications and computer technologies, cellular provides a direct electronic link between individuals—and more important, between the cellular company's switching office and individuals.
Cellular telephone systems, as they become more widespread, may further erode individuals' expectations of privacy, because the cellular operator—or, more significantly, the government with the cooperation of the operator—has the potential capability to keep track of each subscriber in the system. A computer tracking device in the operator's "mobile telephone switching office" (MTSO) must locate each mobile unit geographically so that the MTSO can regulate the phone's frequency as the user moves from one area to another within the system.
"Conceptually, it is possible to track someone's movements around a city, and from city to city" on a cellular system, explains John Simeone, vice president for research and development at Cellular Software, Inc. Simeone, who designs computer software for cellular phone systems, helped install the Los Angeles system for PacTel Mobile Access, the cellular operator there.
Analyst Fred Weingarten, of the Congressional Office of Technology Assessment, agrees that such surveillance is possible. "The system has to 'know' where the person is at all times," he says. "In general, if you know the succession of frequencies [a mobile unit uses during a call] you can chart its path." An FCC official who has worked with cellular technology since its inception also confirms that such electronic tracking is possible.
Moreover, at least one type of cellular switching mechanism records every call by location and records whether the user has moved during the call. According to Mark Nielsen, marketing manager of Cellular Business Systems, Inc., who has advised the American Civil Liberties Union on privacy issues, "the mobile unit's originating location is stored on computer tape." Whoever can gain access to the computer, he says, certainly can roughly determine the subscriber's location when the call was dialed.
"If cellular technology were misapplied, governments could keep an eye on citizens," the industry trade publication Cellular Business has bluntly warned. "Police could see who attends an anti-draft rally, or who in which department or agency is meeting with a reporter. Special lists could be drawn up of real or imagined enemies who deserve closer attention. Far-fetched? Imagine what a Nixon or a McCarthy could have done with this, let alone the totalitarian regimes of the East Bloc and Third World."
Cellular equipment is already being tested as a means of enforcing "incarceration in the home" for convicted drunken drivers, according to Cellular Business. This technique uses a device that, when strapped to an individual's arm or leg, would notify police if the individual leaves a specific area. And technologists are now talking about a "telephone number for life," whereby we would all be christened at birth with a code of digits all our own to carry with us to the grave.
These developments foreshadow the communications age heralded by Megatrends author John Naisbitt, who welcomes the notion that people will always be connected to one another—but they also forewarn the death of privacy. Admittedly, that fear could not be fully realized until the cellular industry is more developed. Current systems are not necessarily programmed to deliver subscriber-location information to the cellular operator in any sort of timely fashion, says cellular-software designer Simeone. Furthermore, the initial systems are configured such that the location function is rather imprecise. But with more and more users, operators will have to reconfigure the systems, which will then be able to more accurately determine subscribers' locations.
Simeone predicts that tracking capability will become universal as systems add on subscribers and as operators upgrade their technology. Moreover, he says, nothing inherent in current cellular hardware precludes an operator from adding a "locate-car" function to the software to deliver such information instantly. This function would instruct the central switching office to send an electronic inquiry to a given subscriber's mobile phone. If the phone is switched on and is within the system, it would electronically send a response back to the switching office, even if the subscriber is not using the phone at the time.
Marketing pressures, in fact, will likely spur cellular carriers to provide more-exact subscriber location information. "Cellular operators are always looking for incremental features they can offer that will enhance their profitability," Simeone says. One such addition is automatic-vehicle-location (AVL) technology, which determines a mobile unit's location by measuring its relative signal strength at three different receiver points.
Such capability, says Simeone, would be attractive to cellular operators because it would enable them to offer subscribers a range of enhanced services, including a way to combat car theft. If, for example, a subscriber is receiving "theft protection" service, the cellular phone may remain activated even while the car's ignition is off, so that its signal may be tracked at any time while it's in the cellular system. No technical modification is required in currently manufactured cellular telephones—the unit need only be hooked up in a certain way to the car's battery power. "Anybody who has a car that costs $15,000 would pay $5 a month for such a service," Simeone suggests.
Cellular marketer Mark Nielsen points to other potential uses of AVL capability. Firms in Hong Kong, he notes, are considering its application as an antiterrorist device. If kidnapped, a subscriber would press a "panic button," thus activating the telephone so that the car's movements could be traced.
An AVL system of this sort is capable of impressive accuracy. According to Nielsen, it can locate a vehicle to within 100 feet. Motorola, a pioneer in cellular technology, has developed an AVL system that, it claims, can locate a vehicle to within one block 95 percent of the time in 95 percent of the coverage area for most cities.
On the surface, such technical capability does not seem all that insidious. After all, businesses and individuals may very well covet such services. The problem arises when overly curious authorities try to bring cellular operators into a "partnership" to support and aid government surveillance activities. By such arrangements, the state can gain access to information far beyond what an individual may have intended by subscribing to cellular services.
To initiate such an arrangement, says Simeone, "the average police authority will go in through the back door—they'll just walk into the MTSO" (mobile telephone switching office). In conversations with telephone-company personnel, he says, he was shocked to learn the extent to which traditional telephone companies have cooperated with the police for such purposes. "A phone employee was very up-front about the fact that, even though my phone number is unpublished, they would release it upon request from a government body without my consent," Simeone reports. "Upon government application for phone records," he adds, the phone company "will provide them even without a court order."
This type of "cooperative" venture has a long history. The telephone was not invented or marketed as a surveillance device, but police were quick to catch on to its capabilities for that purpose. By the 1920s, wiretapping became one of the new tools used by law-enforcement officials.
It is not known how many citizens were bugged before the Supreme Court ruled in 1967 that the privacy of phone conversations is constitutionally protected. But more recent statistics indicate that the technique continues to be popular. In 1971—the peak year of the Vietnam war protests—more than 800 wiretaps were authorized. In 1981, federal and state authorities ordered 589 wiretaps. And between January 1981 and September 1982, the Reagan administration upped its surveillance orders by 280 percent.
Authorities also have also secured the "cooperation" of telephone companies in the installation—without court order—of "pen registers," devices that record the numbers dialed by a person being investigated. Thus any information that subscribers reveal to the telephone company becomes fair game for official snooping. Justice Thurgood Marshall has warned, "Unless a person is prepared to forgo use of what for many has become a personal or professional necessity, he cannot but accept the risk of surveillance."
With cellular telephones, investigative agencies gain an added dimension in their information-gathering capabilities. The development of cellular may enable police to monitor from a centralized location the movements of any subscriber they choose. The comparison to George Orwell's Nineteen Eighty-Four is inescapable:
There was, of course, no way of knowing whether you were being watched at any given moment…it was even conceivable that [the Thought Police] watched everybody all the time.…They could plug in your wire whenever they wanted to. You had to live…in the assumption that…every movement was scrutinized.
Of course, we do not yet live in an Orwellian society, and individuals in the United States are supposed to be protected by a Bill of Rights. These constitutional protections, however, prohibit intrusive practices only when they fit within the law's existing conceptual framework. While the Fourth Amendment protects against unreasonable searches of persons and their effects, use of cellular tracking capabilities would be a search for persons and their effects. Thus, surveillance using cellular technology simply does not fit into the traditional Fourth Amendment mold.
Decisions in analogous areas reinforce the suspicion that the Supreme Court would not extend protection to cellular subscribers. The court has decided, for example, that the police do not need warrants to install pen registers to record telephone numbers, because subscribers "share" the numbers they dial with the telephone company. Presumably, the court would also find that cellular subscribers "share" their locations with the telephone company.
The clearest indication that the Supreme Court would not protect cellular subscribers is its 1983 decision that monitoring a suspect's movement with a "bumper beeper" is neither a search nor a seizure under the Fourth Amendment. Writing for the majority, Justice William Rehnquist stated:
A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy in his movements from one place to another. When [the defendant] traveled over the public streets, he voluntarily conveyed to anyone who wanted to look, the fact that he was traveling over particular roads in a particular direction, the fact of whatever stops he made, and the fact of his final destination when he exited from public roads on to private property.
"Nothing in the Fourth Amendment," the court added, "prohibited the police from augmenting the sensory faculties bestowed upon them at birth with such enhancement as science and technology afford them in this case."
A March 1984 decision of the Kansas Supreme Court and a February 1985 Rhode Island Supreme Court decision further reinforce the idea that cellular systems are beyond constitutional protection. Recording conversations from cordless telephones, the courts ruled, did not violate federal anti-wiretapping laws, because such phones provide their users no reasonable expectation of privacy. The courts reasoned that since conversations on such telephones are transmitted in part via radio waves and not entirely by wire, anyone may legally listen in-including the police.
Although monitoring cellular-telephone conversations on a radio scanner is more difficult than listening in on a traditional car telephone, expert investigators indicate it can be done. Most industry observers simply conclude that if a person thinks his message is important, he shouldn't say it over the air. Once this privacy expectation is extinguished, according to the state-court decisions, so are all legal protections.
John Simeone believes that monitoring cellular conversations should not pose a significant threat to privacy, because he predicts that encryption (scrambling) technology will be available within the next five years to help the average subscriber protect the privacy of his conversations. Such devices are not yet on the market, however, and when they become available they could be prohibitively expensive. Moreover, they would not enable subscribers to keep their locations private.
Clearly, the current Fourth Amendment standard is insufficient to protect cellular subscribers and may be obsolete in a high-tech world. In a society where living rooms are wired to the outside world via interactive cable, where the streets are constantly monitored by closed-circuit cameras, and where any automobile equipped with a telephone can be located instantly, no one can "reasonably expect" privacy. If the right of privacy is to be preserved, the judiciary must develop a new conceptual framework. As one federal appeals court recently noted, the crucial issue is whether investigative activity, if unregulated by constitutional constraints, is the kind of intrusion a free society is willing to tolerate.
Rather than wait for light to dawn at the Supreme Court, however, it makes sense to explore other solutions to privacy problems that may accompany the development of new technologies. The Supreme Court took 40 years to eradicate the mistake it made in Olmstead, which denied Fourth Amendment protection for phone conversations. It may never face the difficult issues raised by its 1967 Katz decision, which articulated the "reasonable expectation of privacy" principle.
Fortunately, Congress has shown a willingness to extend the privacy protections to supplement judicial standards. Congress enacted the Privacy Protection Act of 1980 to prevent newsroom searches by the police after the Supreme Court had sanctioned such tactics in a 1978 decision. Concluding that the Court had allowed the government too much latitude, Congress banned most newsroom searches.
The earlier Omnibus Crime Control and Safe Streets Act (1968) was passed in part to implement the Fourth Amendment wiretapping prohibition. And most recently, Congress inserted language in a 1984 federal cable-television law that requires the government to obtain a court order (and affords the subscriber the opportunity to contest such an order) before authorities are permitted access to personally identifiable information. A similar legislative approach could be used to help prevent abuse of cellular-radio technology. California state senator Herschel Rosenthal, for example, recently proposed a bill in the California legislature to outlaw scanning cellular telephone conversations.
Legislation, however, may suffer from some of the same infirmities as constitutional protections. Statutes may be poorly drafted, or they may fail to anticipate new technological intrusions. Rosenthal's proposed legislation for California, for example, says nothing about monitoring the location of cellular subscribers. There have been additional newsroom searches since Congress enacted a law to prevent them—in 1981, for example, police searched a Boise, Idaho, television newsroom—and the federal wiretap laws have not prevented warrantless surveillance of cordless-telephone conversations, as the Rhode Island and Kansas supreme courts have made clear.
Although remedial legislation might be helpful, the most effective near-term solutions to cellular's privacy-invasion potential appear to be within the grasp of private institutions. Cellular operating companies could resolve not to allow use of their systems for surveillance or investigation without a court order.
"As long as one denies access to the MTSO by government authorities without a court order," notes cellular-software designer John Simeone, "it would be very difficult for them to monitor citizens' movements." Such a stance, he adds, would be in the best interests of the industry, because the industry's reputation and growth could be seriously damaged if it were publicized that any operator was providing unauthorized access to subscriber information.
Privacy protection may even become a marketing tool, whereby competing cellular systems would seek a competitive edge by offering greater security. Mark Nielsen, of Cellular Business Systems, Inc., agrees that the cellular industry could take a leadership role in providing privacy protection.
Similar policies have already been adopted by certain cable systems. In a notable demonstration of corporate responsibility, the Warner-Amex Company refused to disclose the programming choices of its QUBE two-way-cable subscribers in Columbus, Ohio, when a lawyer tried to subpoena this information during an obscenity trial of a local theater owner a few years ago. The defense attorney was trying to show that Taxi Girls, the film for which his client was being prosecuted, was part of contemporary "community standards," because many area residents had viewed it over cable TV. The president of Warner-Amex vowed never to release individual viewing data, and the court settled for a tally of the total number of viewers of the movie in question rather than individual subscriber information.
Other information industries, too, have taken measures to protect their customers' privacy. The Videotex Industry Association, which represents two-way electronic-publishing services, has promulgated guidelines to prohibit information disclosure on individuals unless the individual consents or there is a court order. Similarly, the National Association of Insurance Commissioners has approved a model privacy law designed to set standards for the collection, use, and dissemination of information collected by insurers.
Cellular carriers should—and, in a competitive market, likely will—follow these leads and adopt measures to protect the privacy of their subscribers, perhaps as part of the contract with subscribers. For example, subscribers could have the option of "unlisting" their units in the automatic-vehicle-location function, just as magazine subscribers can have their names deleted from circulation lists that are rented to marketing organizations. Or cellular operators could provide subscribers who opt for the locator service with a coding mechanism to control the times when their mobile phone is tracked. Perhaps the most important measure would be for cellular-telephone companies to contract with their subscribers not to release information without the subscriber's consent or a court order.
Thus, contractual agreements, rather than constitutional rights, may be the most effective way to combat the assault on individual privacy made possible by such technological developments as cellular telephones. Where subscribers' privacy is ensured by contract with an operator whose interest it is to satisfy customers, protections may evolve as rapidly as does the technology that underlies the agreement. The parties can simply modify the agreement to fit new developments. Subscribers protected by such arrangements need not wait for courts and legislatures to adjust to the new realities.
Thus an open, competitive market for cellular-phone service promises to best assure individual privacy in the new communications age. But the question of what constraints government authorities must act under remains an important issue. "There must be no government intrusion into individuals' private lives without court review," says cellular designer Simeone. "The access to data by government authorities has to be addressed. If people don't give a damn, they are going to get an Orwellian nightmare."
Robert Corn is an attorney with the Washington, D C.-based law firm Steptoe & Johnson.
Cellular Phones Come of Age
Cellular-telephone systems are now operating in 44 American cities, and the Federal Communications Commission (FCC) is currently considering applications for such service in the largest 120 markets. This technology, developed over the past 20 years, is just now coming into use—and into the public's awareness. It promises to revolutionize the telephone industry and make mobile phones universally available.
For many, a car telephone is the ultimate status symbol. It evokes images of a top executive making multimillion-dollar deals while his chauffeur drives him to an important meeting. Seeking this communications capability, millions of people purchased CB radios in the 1970s. And telephone-recording units are currently popular items, allowing their owners to monitor important calls while away from home. But despite this widespread demand for mobile communications, old-fashioned pre-cellular car phones had never reached the mass market.
Mobile-telephone service had been incapable of meeting this market demand for a simple reason: a government-enforced shortage of available radio channels. Car phones operate by sending and receiving signals through a radio link to wireline telephone systems, and the FCC—which regulates use of the airwaves in the United States—severely limited the number of available frequencies for this use. It allocated only 23 channels for traditional mobile-phone service, and in New York, because of technological limitations, only a dozen could be used. Consequently, only 12 mobile-phone calls could occur simultaneously in the nation's largest city.
The shortage of frequencies left mobile-telephone companies with two alternatives, neither desirable. They could either limit the number of subscribers, thus creating long waiting lists for service, or they could issue more mobile telephones and exacerbate the congestion problem.
Mobile-telephone companies opted for both sides of this dilemma, and, in many cases, created the worst of both worlds. In 1982, over 25,000 people were waiting for car-telephone service, and the wait was a long one (in Chicago, 12 to 15 years; in White Plains, New York, over 9 years; in New York City, over 5 years; in Fort Lauderdale, Florida, 4 years). Even with such strict limitations on the number of mobile phones, however, it was difficult to get an open frequency. In some areas only one in three calls was successful during peak periods, because the available channels were in use.
Cellular telephones promise to solve both problems by permitting much more efficient use of available radio frequencies (and because the FCC has allocated many more channels to this new service). The technology is far more complex than that employed in traditional mobile phone service. In a cellular system, markets are divided into geographic regions called cells (hence the name), each assigned a bundle of low-power radio frequencies. (Cells can be divided into smaller cells as a system acquires more and more users.) As a car equipped with a cellular telephone travels through a cell, it uses one of the frequencies. Upon entering an adjoining cell, the mobile phone's signal is "handed off" to a new frequency. All of this is accomplished without interrupting the telephone conversation in progress.
The heart of the cellular system is a computer in the "mobile telephone switching office" (MTSO) that locates each mobile unit geographically and switches the unit's frequency as the car moves from cell to cell. This system is much more efficient than the old one, because it allows "frequency reuse"—that is, the same radio frequency can be used simultaneously in distant parts of the same market without interference. Therefore, a cellular system can handle many more times the telephone traffic than a traditional system can, even given the same number of available channels.
Because this approach is such an efficient use of the radio spectrum, some suggest that cellular systems may become the primary telecommunications technology. "The wire loop may become a thing of the past," says one state regulator. "And the wireless loop and the Dick Tracy wrist watch radio may well overtake us.
—R. L. C.
This article originally appeared in print under the headline "Wireless Tapping".