Ultra-wideband (UWB) technology enables high data-rate short-range communica-
tion, in excess of hundredmegabit-per-secondsand up to multi-gigabit-per-seconds,
over a wide spectrum of frequencies, while keeping power consumption at low lev-
els. This low power operation results in a less-interfering co-existence with other
existed communication technologies (e.g., UNII bands).
In addition to carrying a huge amount of data over a distance of up to 230 feet
at very low power (less than 0.5mW), the UWB signal has the ability to penetrate
through the doors and other obstacles that tend to reflect signals at more limited
bandwidths and higher power densities.
Software Radio (SR) is one of the most important emerging technologies for the
future of wireless communication services. By moving radio functionality into
software, it promises to give flexible radio systems that are multi-service, multi-
standard, multi-band, reconfigurable and reprogrammable by software.
Today’s radios are matched to a particular class of signals that are well defined
bytheircarrierfrequencies,modulationformatsandbandwidths.Aradiotransmitter
today can only up convert signals with well-defined bandwidths over defined center
frequencies, while, on the other side of the communication chain, a radio receiver
can only down convert well-defined signal bandwidths, transmitted over specified
carrier frequencies.
A mobile ad-hoc network (MANET) is formed by multiple moving nodes
equipped with wireless transceivers. The mobile nodes communicate with
each other through multi-hop wireless links, where every node can transmit
and receive information. Mobile ad-hoc networks have become increasingly
important in areas where deployment of communications infrastructure is
difficult.
During the past three decades, the world has seen signifi cant changes in the telecom-
munications industry. There has been rapid growth in wireless communications, as
seen by large expansion in mobile systems. Wireless communications have moved
from fi rst-generation (1G) systems primarily focused on voice communications to
third-generation (3G) systems dealing with Internet connectivity and multi-media
applications. The fourth-generation (4G) systems will be designed to connect wire-
less personal area networks (WPANs), wireless local area networks (WLANs) and
wireless wide-area networks (WWANs).
This book is concerned with integrated circuits and systems for wireless and
mobile communications. Circuit techniques and implementation of reconfigurable
low-voltage and low-power single-chip CMOS transceivers for multiband and multi-
mode universal wireless communications are the focus of the book. Applications
encompass both long-range mobile cellular communications (GSM and UMTS)
and short-range wireless LANs (IEEE802.11 and Bluetooth). Recent advances in
research into transceiver architecture, RF frontend, analogue baseband, RF CAD
and automatic testing are reported.
The explosion in demand for wireless services experienced over the past 20 years
has put significant pressure on system designers to increase the capacity of the
systems being deployed. While the spectral resource is very scarce and practically
exhausted, the biggest possibilities are predicted to be in the areas of spectral reuse
by unlicensed users or in exploiting the spatial dimension of the wireless channels.
The former approach is now under intense development and is known as the cogni-
tive radio approach (Haykin 2005).
The planarization technology of Chemical-Mechanical-Polishing (CMP), used for the manufacturing of multi-
level metal interconnects for high-density Integrated Circuits (IC), is also readily adaptable as an enabling technology
in MicroElectroMechanical Systems (MEMS) fabrication, particularly polysilicon surface micromachining. CMP not
only eases the design and manufacturability of MEMS devices by eliminating several photolithographic and film
issues generated by severe topography, but also enables far greater flexibility with process complexity and associated
designs. T
adio Frequency Identification (RFID) is a rapidly developing automatic wireless data-collection
technology with a long history.The first multi-bit functional passive RFID systems,with a range of
several meters, appeared in the early 1970s, and continued to evolve through the 1980s. Recently,
RFID has experienced a tremendous growth,due to developments in integrated circuits and radios,
and due to increased interest from the retail industrial and government.
Radio frequency identification (RFID) and Wireless sensor networks (WSN) are
the two key wireless technologies that have diversified applications in the present
and the upcoming systems in this area. RFID is a wireless automated recognition
technology which is primarily used to recognize objects or to follow their posi-
tion without providing any sign about the physical form of the substance. On the
other hand, WSN not only offers information about the state of the substance
and environment but also enables multi-hop wireless communications.
PW4203 is a 4.5-22V input, 2A multi-cell synchronous Buck Li-Ion battery charger, suitable forportable application. Select pin is convenient for multi-cell charging. 800 kHz synchronous buckregulator integrates of 22V rating FETs with ultra low on- resistance to achieve high efficiency andsimple circuit design.The PW4203 is available in an 8-pin SOP package, provides a very compact system solution andgood thermal conductance
