Patent
Protected amplifier apparatus
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TLDR
In this article, an amplifier incorporating various devices for detecting parameters such as average power, peak power and signal voltage is used to provide the feedback signals for automatic level control of an RF amplifier whose output signal is passed through an antenna coupler to an antenna.Abstract:
This disclosure relates to an amplifier incorporating various devices for detecting parameters such as average power, peak power and signal voltage to be used to provide the feedback signals for automatic level control of an RF amplifier whose output signal is passed through an antenna coupler to an antenna. These detection devices allow normal operational level setting as well as minimizing the chance of overloads resulting in amplifier circuit failure during tuning conditions.read more
Citations
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Methods and Apparatuses for Adaptively Controlling Antenna Parameters to Enhance Efficiency and Maintain Antenna Size Compactness
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Kazimierz Siwiak,David H. Minasi +1 more
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References
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Patent
Circuit to protect rf output amplifier against mismatch damage
TL;DR: In this article, a mismatch protection circuit is proposed to protect power output transistors of a communications transmitter from damaging excessive reflected power, as might occur when the antenna is disconnected or broken, which circuit continuously monitors and compares parameters indicative of forward and reflected power or VSWR and when there is excessive mismatch, instantaneously cuts back the dc power delivered to the transistors to a safe low level, but a level sufficient for continued cutback operation of the protection circuit, when and for so long as the excessive mismatch continues.
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