General English Programs

The radio, reinvented

Almost exactly a century ago, on 12th December 1901, Italian inventor Guglielmo Marconi sat in Newfoundland, Canada, listening through and earphone for signals that few believed he would ever receive. But arrive they did, just after noon, from the far side of the Atlantic in Cornwall, England. The faint pip-pip-pip was merely the letters broadcast in Morse code, but in it, Marconi heard the future, “I now felt for the first time absolutely certain that the day would come when mankind would be able to send messages without wires”, he wrote, “Not only across the Atlantic but between the farthermost ends of the earth.”

At that moment began an era of “wireless” innovations that continues through this day, simultaneously shrinking distances between people from all corners of the world and expanding our imaginings about what is possible. By 1920, the first radio station began broadcasting from Pittsburgh,and by the 1930’s, the radio console was the central feature of nearly every American living room. Next, radio-wave technology gave birth to the television, and by the 1940’s there were 23 television stations broadcasting throughout the United States. In the decades that followed, radio waves were harnessed in new devices, from radar to microwave ovens, garage door openers to communication satellites, baby monitoring systems to cellphones, pagers, and the global positioning system. Now, at the turn of the century, Marconi’s vision is about to take on a new life. In a decade or so, researchers say, a host of technologies will come together to create a kind of global wireless Web.

Based on new ways of squeezing signals onto the airwaves, new schemes for relaying them around the globe, and smart, all-in-one terminals, the wireless Web would let any person communicate with any other person, anywhere, anytime, sending any imaginable kind of text, sound, or video. Virtually every government and communications firm on Earth is gearing up for this “tetherless” world. It could stimulate an increase in productivity comparable to that yielded by the Internet itself, says John Cozzens, a program director with the National Science Foundation’s Computer-Communications Research division. “And socially”, he adds, “ I don’t think most of us can even imagine the implications”.

Radio waves have such enduring promise because, travelling at the speed of light, they can carry Information across vast distances almost instantly, in some cases shrugging off obstacles such as buildings and hilltops. In the continuum of electromagnetic waves, radio waves are the longest type, with a wave length ( the distance between any two wave crests ) that can span a few feet or even a few miles, which is what lets them ignore most barriers. Short, high-frequency radio waves, just fractions of an inch long, are called microwaves; even shorter are infra-red, visible, and ultraviolet light, then x-rays, and finally gamma rays, with infinitesimal wavelengths smaller than one atom.

The atmosphere today is so saturated with man-made radio signals that if they were all visible, we would be dazzled by the sight of thousands of different waves- carrying sportscasts and military communications and wireless E-mail and cellphone calls- passing through or bouncing off our bodies at any given moment. Because each television network, each cellphone carrier, each radio station needs its own frequency, or portion of the spectrum, radio resources are finite, and slices of available spectrum are rare and precious.

But just when radio communications seem to be crowded to their limit, new technologies are Emerging to load up the airwaves with still more data, in wider-reaching networks. Many wireless Networks already exist : E-mail services such as Blackberry; mobile phones; and the Bluetooth technology that keeps separate devices such as laptops, hand-held computers, and MP3 players in constant communication with one another within a house or building. But many of these small systems cannot handle the massive volume and variety of data needed to carry multimedia transmissions, and even those that can are often unable to interact with other systems.

“We live in a world of dump-truck technology”, says Bob Miller, head of communications research at AT&T Labs, “ where new capabilities are unloaded in front of us with no thought to how they can be integrated into a larger framework.” That’s a major obstacle to “global seamless roaming”, says David McCartney, president of a wireless start up company called e-tenna. To overcome it, labs are developing what McCartney calls “agile” technologies that would allow a wireless user to migrate from system to system and country to country without ever losing a connection.

Still, no single innovation will be enough, and companies are gambling huge sums – a trillion dollars in Europe alone, by one estimate – to create a totally connected world. Another key prerequisite is freeing up enough of the radio spectrum to carry the torrents to wireless information, including CD-quality sound and crystal-clear video, that might course through the network. Some cellular phone networks, for example, eat up precious radio bandwidth, because once a cell is initiated, a single frequency has to be dedicated to it, even if not much information is travelling. It’s the equivalent of devoting and entire lane in a highway to a single car. Sharing the road. A wireless version of the “packet switching” technology used by the Internet could Allow many users to share the exact same frequency, like many cars travelling in the same lane.

The idea is to break up each transmission into tiny snippets of digital data that would slip into the stream whenever there is space. Until now, packet switching has been ill-suited to transmitted video and voice, because the lags between packets can create distortion. But Lucent Bell Labs is developing protocols for wirelesss systems that create a more orderly transmission, reducing the lags to milliseconds, too short for the human brain to notice a delay. To all of the users sharing the same frequency, the connection would seem unbroken.

Even with enough bandwidth for everyone, there remains the question of how to get the right signals from one user to another, wherever they many both be wandering. Satellites are ideal for relaying signals around much of the globe. But the microwaves they rely on, though able to penetrate the atmosphere from space, can only reach their target if unimpeded by obstacles like trees, houses, or thunderstorms.

That’s why satellite dishes have to have a clear view of the sky. Getting signals from a satellite to or from receivers on cars or hand-held devices is a tall order.

A new innovation unveiled this month, digital satellite radio, attempts to solve these problems by employing ground-based “repeaters”. The radio signals – programming available by subscription across the country- emanate from a satellite, but strategically placed antennas receive the signals and relay them to passing pedestrians or vehicles. Some researchers think these kind of handoffs will be critical to the future worldwide network. In their scenario, every single mobile device that happens to be in use in the given area would act as a repeater, co-operatively helping signals to reach their destination. As on the Internet, separate segments of a single transmission might follow many different paths to their destination. “ The connections will be very organic, not painstakingly mapped out as today’s cellphone grids are,” says Miller.

But most agree that the “biggest challenge of the wireless world is designing a communications tool that can send, pick up, and display all the different kind of wireless date surging through the airways-and still fit into a pocket. “Until now, a TV has been a TV, a radio a radio, a phone a phone,” says Miller. “ But now, you have to teach a single machine to decide which of many different radio technologies to make use of”.

This “software-defined radio” would scan the spectrum for signals, then transform itself into and e-mail portal, a telephone, a radio, or a videophone depending on what it picked up. When the user wanted to reply, the device would assess the kind of data being sent and the capabilities of the local wireless system, then fashion the outgoing transmission. And all this wizardry would have to take place swiftly and invisibly. “All our customers will be aware that they are getting a better experience”, says Paul Mankiewich, Lucent’s chief architect of mobility solutions. Good things to come – It will take years to work out the details, says the National Science Foundation’s Cozzens. But when that happens, he expects a host of societal benefits. Among them : better crisis Management through videoconferencing that would put workers at the scene in instant contact with Experts, telemedicine that can save patients from a distance, and more sophisticated education for rural schools that lack the Internet capacity for multimedia and instantaneous two-way interactions.

Some entrepreneurs even envision wireless virtual reality, in which the air-waves would carry not only just voice, but also a sense of being in a remote location. With the right kind of communications portal, we might “try on” clothes at a store across the country, meet with holograms of our distant colleagues, and feel the warmth of Grandma’s cheek as we kiss it through the ether from thousands of miles away.

But it doesn’t take futuristic scenarios to prove the value of an always-connected world. “I’ve always been the last person to see the need for a cellphone or for a DVD player”, says e-tenna Vice President Andy Humen. “But even I realize that once I can get the data I now get on my desktop anywhere I happen to be, I won’t be willing to give that up”. Neither, he is venturing, will most of us.

Questions 27-31

Answer the following questions, using NO MORE THAN THREE WORDS for each answer. Write your answer in boxes 27-31 on answer sheet.

27) In which country did the first radio station begin broadcasting by 1920?

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28) In the continuum of the electromagnetic waves, which one has the shortest length?
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29) As far as technology is concerned, which word does the author use to describe the future world?

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30) What metaphor does the author use to explain the new wireless communications technology?

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31) Which machine can send, pick up, and display all the different kinds of wireless data through
the airways?

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Questions 32-36

Choose the appropriate letters A-D write them in in boxes 31-35 on the answer sheet.

32) At the times of Marconi, people’s attitude to his experiment was that …

A) they were excited about it
B) only Marconi thought it was possible
C) very few, if any, had confidence in it
D) even Marconi was not sure of its success

33) Which of the following is NOT a feature of the future global wireless web?

A) New schemes of squeezing and relaying more signals
B) Allowing numerous simultaneous communications
C) Transmitting any available information
D) Stimulating increase in productivity

34) Radio waves don’t have a bright future because of …

A) their travelling speed
B) the vast distance they travel
C) their wavelength
D) the ability to surmount obstacles

35) According to the passage, the radiowaves are responsible for carrying ALL the following messages
EXCEPT …

A) all telephone calls
B) radio and TV broadcasting
C) wireless e-mails
D) military communications

36) The obstacles to a totally connected world include …
A) too many technologies being unloaded in front of us
B) too much free bandwidth in the radio spectrum being available
C) getting right signals from one user to another
D) designing and all-powerful communications tool

Questions 37-41
Complete each of the following statements ( Questions 36-40) with words taken from Passage 3. Write NO MORE THAN THREE WORDS for each answer.

37) The first radio message sent over a long distance in 1901 was written in

…………………………………………………………………………….

38) The distance between any two …………………………………………………..of the radio waves is
about a few feet to a few miles long.

39) The problem with many of the already-existent wireless networks are either their inability to
………………………………………………………. or their inability to communicate with
other systems.

40) Human brain can not detect the lags between pieces of information transmitted if they are ………..
………………………………………………………….

41) Apart from other societal benefits, ………………………………………….might even carry a sense
of being in a remote location.