Pulse intelligent radio-frequency modulation controller

Abstract

The present invention provides a method for controlling the output of a generator. This output provides an output signal with settling time to an impedance load. The settling time of the output signal is determined. The output signal is amplitude modulated with the modulating waveform. A sense signal representing the modulated output signal is generated. The sensing signal is sampled with a sampling time determined based on the settling time of the output signal. A digital representation of the sampled sensor signal is formed. Amplitude modulation of the output is controlled based on the digital representation of the sampled sense signal.

Description

technical field [0001] This invention relates generally to generators providing a power output, and more particularly to power generators providing a modulated output waveform. Background technique [0002] Generators that provide a modulated output are limited in several ways by the waveform sensing / control technology used to control the output. Typically, conventional generators use a control method that tracks the rising edge of a sense signal representing the output waveform. A charge-discharge-hold circuit (CDH circuit) is used to track the rising edge of the sensing signal. The CDH circuit continues to track the waveform until the value of the sensed signal is measured after a predetermined time equivalent to the settling time of the device. A holdover circuit is activated at the same time that the output modulation is disabled, providing an effective continuous DC output independent of the modulation parameters. By multiplying the measured parameter by the duty cyc...

AI Technical Summary

Problems solved by technology

The inability to track rising and falling edges at the same time limits this control technique to controlling output waveforms where, during the low period of the modulating waveform, the pulse returns to 0

Without the ability to simultaneously track the rising and falling edges, it is usually difficult to control a modulated waveform of any amplitude

Therefore, unless the generator system can tolerate the inaccurate generation and measurement of various output characteristic parameters, conventional generator control techniques are generally limited to controlling the pulse output waveform

[0005] Conventional generator control techniques can be used to provide a modulated output waveform under limited operating conditions, those techniques have not been proven to provide generators that are not limited by sensor / measurement circuits

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