Radio City

There are a lot of ways to get your data fix while out and about, and even more are on the way. Because radio waves interact with the physical environment to a vastly greater degree than signals isolated within a copper or fiber-optic cable, which technology works best for you often depends on where you are.

In cities, buildings block and reflect signals, creating dead zones and bandwidth-sapping interference. High population density can make capacity demands difficult to manage, especially in business districts that on weekdays are flooded with smart-phone-wielding commuters. New 4G technologies should be able to handle reflection better and carry more data, easing congestion (see “Feeding the Bandwidth Beast” ).

In rural areas, low population density means that people are often outside the range of cell towers, because there aren’t enough customers to cover the cost of providing comprehensive coverage. Networks that make use of white spaces–unused long-range frequencies in the portion of the spectrum traditionally used by television broadcasters (see “New Spectrum from Old”)–could be a boon for places like these, especially given that a lower population density often means fewer TV stations, leaving more of the spectrum free for data. But even cities will get a boost from white-space technology: the signals can penetrate buildings better than many current wireless alternatives.

Meanwhile, new satellites are delivering services that can provide two-way broadband connections to millions of users. These, too, should benefit rural areas and underserved areas of cities.

Interactive credit: Allistar Halliday