Abstract: Wireless sensor networks have been used in wide
areas of application and become an attractive area for researchers in
recent years. Because of the limited energy storage capability of
sensor nodes, Energy consumption is one of the most challenging
aspects of these networks and different strategies and protocols deals
with this area. This paper presents general methods for designing low
power wireless sensor network. Different sources of energy
consumptions in these networks are discussed here and techniques for
alleviating the consumption of energy are presented.
Abstract: Fiber optic sensor technology offers the possibility of
sensing different parameters like strain, temperature, pressure in
harsh environment and remote locations. these kinds of sensors
modulates some features of the light wave in an optical fiber such an
intensity and phase or use optical fiber as a medium for transmitting
the measurement information.
The advantages of fiber optic sensors in contrast to conventional
electrical ones make them popular in different applications and now a
day they consider as a key component in improving industrial
processes, quality control systems, medical diagnostics, and
preventing and controlling general process abnormalities.
This paper is an introduction to fiber optic sensor technology and
some of the applications that make this branch of optic technology,
which is still in its early infancy, an interesting field.
Abstract: A 2.4GHz (RF) down conversion Gilbert Cell mixer,
implemented in a 0.18-μm CMOS technology with a 1.8V supply, is
presented. Current bleeding (charge injection) technique has been
used to increase the conversion gain and the linearity of the mixer.
The proposed mixer provides 10.75 dB conversion gain ( C G ) with
14.3mw total power consumption. The IIP3 and 1-dB compression
point of the mixer are 8dbm and -4.6dbm respectively, at 300 MHz
IF frequencies. Comparing the current design against the
conventional mixer design, demonstrates better performance in the
conversion gain, linearity, noise figure and port-to-port isolation.