OSCILLATORS are key building blocks in integrated transceivers. In wired and
wireless communication terminals, the receiver front-end selects, amplifies and
converts the desired high-frequency signal to baseband. At baseband the signal can
then be converted into the digital domain for further data processing and demodula-
tion. The transmitter front-end converts an analog baseband signal to a suitable high-
frequency signal that can be transmitted over the wired or wireless channel.
Radio frequency (RF) power amplifiers are used in everyday life for many applica-
tions including cellular phones, magnetic resonance imaging, semiconductor wafer
processing for chip manufacturing, etc. Therefore, the design and performance of
RF amplifiers carry great importance for the proper functionality of these devices.
Furthermore, several industrial and military applications require low-profile yet
high-powered and efficient power amplifiers.
Orthogonal frequency division multiplexing (OFDM) has been shown to be
an effective technique to combat multipath fading in wireless channels. It
has been and is going to be used in various wireless communication systems.
This book gives a comprehensive introduction on the theory and practice of
OFDM for wireless communications.
The single-carrier frequency division multiple access (SC-FDMA)
system is a well-known system that has recently become a preferred
choice for mobile uplink channels. This is attributed to its advantages
such as the low peak-to-average power ratio (PAPR) and the use of
frequency domain equalizers. Low PAPR allows the system to relax
the specifications of linearity in the power amplifier of the mobile
terminal, which reduces cost and power consumption.
Recent advances in wireless communication technologies have had a transforma-
tive impact on society and have directly contributed to several economic and social
aspects of daily life. Increasingly, the untethered exchange of information between
devices is becoming a prime requirement for further progress, which is placing an
ever greater demand on wireless bandwidth. The ultra wideband (UWB) system
marks a major milestone in this progress. Since 2002, when the FCC allowed the
unlicensed use of low-power, UWB radio signals in the 3.1–10.6GHz frequency
band, there has been significant synergistic advance in this technology at the cir-
cuits, architectural and communication systems levels. This technology allows for
devices to communicate wirelessly, while coexisting with other users by ensuring
that its power density is sufficiently low so that it is perceived as noise to other
users.
Once upon a time, cellular wireless networks provided two basic services: voice
telephony and low-rate text messaging. Users in the network were separated
by orthogonal multiple access schemes, and cells by generous frequency reuse
patterns [1]. Since then, the proliferation of wireless services, fierce competition,
andthe emergenceof new service classes such as wireless data and multimediahave
resulted in an ever increasing pressure on network operators to use resources in a
moreefficient manner.In the contextof wireless networks,two of the most common
resources are power and spectrum—and, due to regulations, these resources are
typically scarce. Hence, in contrast to wired networks, overprovisioning is not
feasible in wireless networks.
There is an unprecedented enthusiasm for radio frequency
identification (RFID) technologies today. RFID is based on the
exchange of information carried by electromagnetic waves between a
label, or tag, and a reader. This technology is currently in full
economic expansion, which has manifested itself in widely backed
research activities, some of which will be examined in this book.
Radio frequency identification (RFID) is a type of automatic identification systems
which has gained popularity in recent years for being fast and reliable in keeping
track of the individual objects. In RFID systems, contactless object identification
is achieved using radio signals without the need for physical contact as the case
with other existing identification technologies such as barcodes. Therefore, a huge
number of items can be identified in a short amount of time with high reliability
and low cost which makes the RFID technology very attractive for a wide range of
applications such as supply chain management, e-health, monitoring humans, pets,
animals, and many other objects, toll control, and electrical tagging. Furthermore,
RFID technology eliminates the human error and reduces the total cost of the
products.
The PW5410B is a low noise, constant frequency (1.2MHz) switched capacitor voltage doubler. Itproduces a regulated output voltage from 1.8V to 5V input with up to 100mA of output current. Lowexternal parts count (one flying capacitor and two small bypass capacitors at VIN and VOUT) makethe PW5410B ideally suited for small, battery-powered applications
