Diode lasers have many advantages such as small size, high efficiency and small
angular dispersion of the collimated beam. However they also have some problems like
lack of frequency stability. They can not be tuned in wavelength. An external cavity can
solve these problems and decrease the laser linewidth.
To...
As screen resolution and video decoding capability have increased, high-definition (HD) video in resolutions as high as 1920 x 1080 is rapidly becoming the standard. Ad-hoc streaming of HD video over 802.11 wireless networks, e.g., streaming from a mobile device to a television, is convenient for users, but is hampered...
The electrical properties of ion-implanted GaAs FET channels
are investigated by two methods. First, the channel current (I) as
a function of voltage (V) is examined at different temperatures and
using different voltage ramp rates. The standard FET I-V curve,
which can be observed on a commercial curve tracer, is...
Harvesting energy from ambient sources can provide power autonomy to energy efficient electronics and sensors. The last decade has seen a multitude of ways to scavenge energy from various sources like solar, thermal, electromagnetic, electrostatic, piezo-electric and many more. Thermal energy from human body heat is ubiquitous and can be...
A duty-cycle controlled switched resistor is a tunable resistive element that uses pulse width modulation as the method of tuning. This thesis will describe the operation of switched resistors and propose several circuit architectures that are well suited to the use of switched resistors. These architectures include filters, mixers, and...
Traditional approaches to streaming H.264 video over a network typically rely on a single method of transport (i.e., reliable or unreliable) and/or use static values for parameters that can have a significant negative impact on the perceptual quality of the received video. This dissertation presents a dynamic method for wireless...
The application of information theory and digital signal processing techniques to digital
communication has resulted in robust methods for reliable high speed data transmission
over noisy channels environments. Among these methods, multicarrier systems have
become a viable solution for exploiting maximum spectral efficiency over both wideband
highly dispersive static and...
Most technological problems associated with man-machine conversations
have been solved and are well documented in both the
contemporary technical and lay literature. The major remaining
technological problem is the real time conversion of a human's vocal
uterances into a "written" phoneme sequence representing the information
content of speech. The work...