Commercially available active noise control headphones rely on fixed analog controllers to drive "anti-noise" loudspeakers. Our design uses an adaptive controller to optimally cancel unwanted acoustic noise. This headphone would be particularly useful for workers who operate or work near heavy machinery and engines because the noise is selectively eliminated. Desired sounds, such as speech and warning signals, are left to be heard clearly. The adaptive control algorithm is implemented on a Texas Instruments (TI™ )
1
TMS320C30GEL digital signal processor (DSP), which drives a Sony CD550 headphone/microphone system. Our experiments indicate that adaptive noise control results in a dramatic improvement in performance over fixed noise control. This improvement is due to the availability of high-performance programmable DSPs and the self-optimizing and tracking
capabilities of the adaptive controller in response to the surrounding noise.
Connecting 32-bit controlled applications
in the industrial, commercial and consumer
markets is fast becoming a necessity rather
than an option. Many new applications, such
as remote data collection, home automation
and networked appliances, require secure,
high-performance connectivity at an
economical price. Freescale Semiconductor
gives design engineers the flexibility to choose
the right 32-bit microcontroller from a broad
portfolio of ColdFire? embedded controllers.
This introduction takes a visionary look at ideal cognitive radios (CRs) that inte-
grate advanced software-defined radios (SDR) with CR techniques to arrive at
radios that learn to help their user using computer vision, high-performance
speech understanding, global positioning system (GPS) navigation, sophisticated
adaptive networking, adaptive physical layer radio waveforms, and a wide range
of machine learning processes.
Micro-Electro-Mechanical Systems (MEMS) are miniature systems composed
ofintegratedelectricalandmechanicalpartstosenseand/orcontrolthingsonaμmscale.
The concept of MEMS is attributed to Richard Feynman’s famous talk on December
29th, 1959 [2,3]. Dr. Feynman foresaw many aspects of future MEMS development
with his insight in microphysics. In particular, material properties in the μm scale are
differentfrombulkpropertiesandthescalingdownofintegratedcircuits(IC)fabrication
technology has been a major driving force of MEMS development.
Power Electronics is one of modern and key technologies in Electrical and
Electronics Engineering for green power, sustainable energy systems, and smart
grids. Especially, the transformation of existing electric power systems into smart
grids is currently a global trend. The gradual increase of distributed generators in
smart grids indicates a wide and important role for power electronic converters in
the electric power system, also with the increased use of power electronics devices
(nonlinear loads) and motor loadings, low cost, low-loss and high-performance
shunt current quality compensators are highly demanded by power customers to
solve current quality problems caused by those loadings.
A power semiconductor module is basically a power circuit of different
materials assembled together using hybrid technology, such as semiconduc-
tor chip attachment, wire bonding, encapsulation, etc. The materials
involved cover a wide range from insulators, conductors, and semiconduc-
tors to organics and inorganics. Since these materials all behave differently
under various environmental, electrical, and thermal stresses, proper selec-
tion of these materials and the assembly processes are critical. In-depth
knowledge of the material properties and the processing techniques is there-
fore required to build a high-performance and highly reliable power module.
This reference design describes the design of a 3-phase AC induction
vector control drive with position encoder coupled to the motor shaft. It
is based on Motorola’s DSP56F805 dedicated motor control device.
AC induction motors, which contain a cage, are very popular in variable
speed drives. They are simple, rugged, inexpensive and available at all
power ratings. Progress in the field of power electronics and
microelectronics enables the application of induction motors for
high-performance drives, where traditionally only DC motors were
applied. Thanks to sophisticated control methods, AC induction drives
offer the same control capabilities as high performance four-quadrant
DC drives.
Research on microwave power amplififiers has gained a growing importance demanded by the many continuously developing applications which require such subsystem performance. A broad set of commercial and strategic systems in fact have their overall performance boosted by the power amplififier, the latter becoming an enabling component wherever its effificiency and output power actually allows functionalities and operating modes previously not possible. This is the case for the many wireless systems and battery-operated systems that form the substrate of everyday life, but also of high-performance satellite and dual-use systems.
