The radio spectrum is one of the most precious resources which must be managed to ensure efficient access for the wireless communication services which use it. The allocation and management of spectrum are administered by the regulatory authorities. Traditionally, spectrum allocation is carried out exclusively of its use in large geographic areas and assigning frequency bands to specific users or service providers is proved to be inefficient. Recently, substantial knowledge about dynamic spectrum access scheme has been accumulated to enable efficient spectrum sharing.
标签： Management Spectrum Access and
上传时间： 2020-05-31
上传用户：shancjb
Contamination and electrostatic discharge (ESD) are now becoming recognized as factors affecting yield and reliability in an ever-increasing number of industries. Whereas contam- ination Traditionally was recognized as affecting the semiconductor, disk drive, aerospace, pharmaceutical, and medical device industries, today such industries as automobile and food production are also discovering the benefits of contamination control. ESD control has experienced a similar growth in applications.
标签： Contamination Control and ESD
上传时间： 2020-06-05
上传用户：shancjb
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.
标签： Reference Designer Manual Phase DRM 023 AC
上传时间： 2020-06-09
上传用户：shancjb
