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Definition
UWB is a wireless technology that transmits binary data-the 0s and 1s that are the digital building blocks of modern information systems. It uses low-energy and extremely short duration (in the order of pico seconds) impulses or bursts of RF (radio frequency) energy over a wide spectrum of frequencies, to transmit data over short to medium distances, say about 15-100 m. It doesn't use carrier wave to transmit data.

UWB is fundamentally different from existing radio frequency technology. For radios today, picture a guy watering his lawn with a garden hose and moving the hose up and down in a smooth vertical motion. You can see a continuous stream of water in an undulating wave. Nearly all radios, cell phones, wireless LANs and so on are like that: a continuous signal that's overlaid with information by using one of several modulation techniques.

Now picture the same guy watering his lawn with a swiveling sprinkler that shoots many, fast, short pulses of water. That's typically what UWB is like: millions of very short, very fast, precisely timed bursts or pulses of energy, measured in nanoseconds and covering a very wide area. By varying the pulse timing according to a complex code, a pulse can represent either a zero or a one: the basis of digital communications.

Wireless technologies such as 802.11b and short-range Bluetooth radios eventually could be replaced by UWB products that would have a throughput capacity 1,000 times greater than 802.11b (11M bit/sec). Those numbers mean UWB systems have the potential to support many more users, at much higher speeds and lower costs, than current wireless LAN systems. Current UWB devices can transmit data up to 100 Mbps, compared to the 1 Mbps of Bluetooth and the 11 Mbps of 802.11b. Best of all, it costs a fraction of current technologies like Blue-tooth, WLANs and Wi-Fi.

The concepts of communication and computation are so close that their tight connection is obvious even for PR departments of major IT companies. Quite often it makes no sense to separate these concepts. Today, speaking about growing power of computing devices we imply both growing performance of their processors and growing throughput of their communication channels. The communication channels include internal:

" caches
" system buses
" memory interfaces
" interfaces of storage devices
...and external:
" interfaces of peripherals
" wireless network channels
" wired network channels
structures of data transfer.

External wired communication channels are developing mainly in two directions - cost reduction and increase of availability of optical channels (top-down) and growth of throughput (bottum-up). However, the two physical carriers are not so close yet (first of all, in prices) to be involved in direct competition - in 90% of cases a character of a problem to be solved determines the technology to be preferred.

Internal wired channels are switching over from specialized parallel interfaces to high-level serial packet interface (Serial ATA, 3GIO/PCI Express, Hyper Transport). It fosters a convergence of external and internal communication technologies: in future separate components of a computer case will be combined into a normal network. It's quite a logical solution - a modern chipset, thus, works as a network switch equipped with multiple interfaces such as a DDR memory bus or a processor bus and AGP/PCI.

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