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could be targeted within smaller bands of frequencies, there was never enough spectrum to go around.
    Governments seized the right to regulate the radio spectrum. In the United States the authority was the Federal Communications Commission (FCC), in Britain it was the Home Office and the Post Office, and so on. But since radio waves are no respecters of national boundaries, national governments had to concede that international regulation had to take place too. Here there was a precedent. In the mid-19th century, the question of how to organise global telegraph communications had prompted the creation of one of the first truly international organisations: the International Telegraph Union (ITU), with headquarters in the neutral Swiss city of Geneva. With the arrival of the fixed-wire telephone in the late 19th century it made sense to extend the ITU’s powers over the new technology. Likewise, the ITU was on hand to provide an organisational structure to regulate international frequency allocation for radio. Every few years, giant international conferences would decide, given existing and predicted use of radio, which services should be allocated a small slice of rare spectrum. These highly technical meetingsreflected the world as we know it: engineers and bureaucrats sought to balance demands for new lifestyle electronics, such as music radio stations, with the commercial necessities of reliable navigation aids, and with the conflicting military imperatives of the technological infrastructures of World War and Cold War armed forces.
    In these decades, a phone that worked by radio was a simple enough proposition, but was impossible to imagine as a truly everyday and popular device, since there was no way to squeeze its demands into an overcrowded spectrum already dominated by the powerful commercial and military interests of the 20th century. Each radio would have to work on a separate frequency from its neighbours, otherwise calls would be interfered with, confused, or, worse, eavesdropped. So the radio telephone was restricted to a privileged handful.
    But in 1947, engineers at Bell Laboratories in the United States proposed a radically new means of imagining mobile radio. It was already shaping up to be a vintage year for Bell Labs. Pump-primed by massive expenditure to develop electronics during the Second World War, the peacetime years saw a string of lucrative discoveries. William Shockley, John Bardeen and Walter Brattain had devised the transistor, the electronic component announced to the public in 1948 that would sweep away bulky valves and lead to the revolutionarylightweight electronics of the second half of the 20th century. Down a few corridors from the transistor pioneers, D.H. Ring, assisted by W.R. Young, put pen to paper, and the result was a description of the ‘cellular’ idea. It was a means of saving spectrum.
    Chapter 3
The cellular idea
    Ringhad written down the principles on which your mobile phone works. Imagine a map of a city and imagine a clear plastic sheet, ruled with a grid of hexagons, placed over it. Now, imagine a car, equipped with a radio telephone, driving through the streets of New York City, passing from hexagon to hexagon (see diagram below).
    Reusing frequencies creates a pattern of ‘cells’.
    Ring’s idea was as follows. If each hexagon, too, had a radio transmitter and receiver, then the radio telephone in the car could correspond with this ‘Base Station’. The trick, said Ring, was to allocate, say, sevenfrequencies to a pattern of seven hexagons (‘a’–‘g’), and to repeat this pattern across the map. The driver would start by speaking on frequency ‘a’ in the first hexagon, then with ‘g’, then ‘c’, and then back to ‘a’ again. Now if the first and last hexagon were far enough apart so that the two did not interfere with each other (and this was possible, especially if low-powered