UWB is a wireless technology that transmits binary dataâ€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 15â€100 m. It doesnâ„¢t use carrier wave
to transmit data.
Current radio technology - 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. Nearly all radios, cell phones, wireless
LANs and so on are like that: a continuous signal thatâ„¢s overlaid
with information by using one of several modulation techniques.
UWB technology - picture the same guy watering his lawn with a swiveling
sprinkler that shoots many, fast, short pulses of water. Thatâ„¢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.
Advantages “ Current UWB devices can transmit data up to 100
Mbps, compared to the 1 Mbps of Bluetooth and the 11 Mbps of 802.11b.
Itâ„¢s expected to reach around 500 Mbps by 2004. Also, this low
power pulse can penetrate obstacles like doors, walls, metal etc. It
doesnâ„¢t require allocation of Ëœpreciousâ„¢ or
Ëœpaid forâ„¢ narrow-band spectrum, in use now. Best of all,
it costs a fraction of current technologies like Blue-tooth, WLANs and
Wi-Fi. UWB doesnâ„¢t suffer from multi-path interference (where
signals reach the receiver after traveling through two or more paths).
Hence, it can be used in densely built-up places, or where number of
users are more than what is supported by Wi-Fi, Blue-tooth etc.A UWB
phone uses so little power that it can remain on for weeks without
recharging.
