Wireless
When Guglielmo Marconi was granted patents on his “wireless telegraph” in 1897, the radio signals could travel only a few kilometres, and only one receiver and transmitter could operate in any one area. Since 1900 “spectrum efficiency” — the amount of information that can travel over the same portion of radio waves — has improved perhaps a trillion times.
The processing power of chips doubles about every two years, according to Moore’s law. As the billions of transistors on the chips get smaller, there is more room to add extra functions.
Many of the functions of such chips are controlled by software, which means they can be continually upgraded at little cost. Chip technology has not only improved the performance and cost of the radio itself but other parts of the system too, from “smart” antennae to advanced power management for longer battery life.
Around 12% of address traffic involves computers linking to other computers, without a person at either end. John Roese expects the amount of machine-to-machine communication to pull ahead of human calls and web clicks some time between 2009 and 2011 as cameras, cars, utility meters, home security systems and the like continuously send data across the network. Vivek Ranadivé, the boss of Tibco, says the number of computer transactions automatically started by other computers is already higher than that initiated by people.
In 2003 Texas Instruments began work on a single low-cost radio chip that included support for a digital music player, FM stereo radio, camera and colour display with a longer battery life. A prototype was built in 2004 and bulk production began in 2006. In the fourth quarter of last year alone the firm shipped 10 million of these chips. The chips have dropped from $50 apiece to around $5, and a phone that would have cost $250 five years ago is now $25.
A simple kind of chip called a radio-frequency identification (RFID) tag, which sends a tiny quantity of data over a short range when activated, can already be manufactured for four cents apiece. Hitachi has a prototype chip that fits into the groove of a thumb-print. Last year one billion RFID chips were sold.
Most big logistics companies in America and Europe now track their fleets with a combination of satellites and mobile-phone networks. Small wireless sensors monitoring equipment in large factories can provide early warning of impending breakdown. They can run on energy “harvested” from the heat or vibrations of the machinery.
One of the most important consequences of these new wireless technologies will be to increase visibility and accountability. Economists today treat many items as indirect costs because there is no way to attribute the use of a resource to a particular individual. Wireless communications can change this, he says, by making it possible to base things like road tolls and car-insurance premiums on people’s actual driving patterns.
Wireless technology is akin to the electrical grid, which was originally intended for a particular use, the light bulb, but whose “killer application” turned out to be the power socket that allowed a multitude of new and unforeseen devices to draw energy from it.
“Marconi’s brainwave,” The Economist