| 摘要 |
<p>An electrical neuro-stimulator using pulse generators (10) providing a master frequency, a carrier frequency, a first modulation frequency and a second modulation frequency. A pair of multivibrators (16) and (18) produce a pulse train output with an adjustable number of impulses by adjustment of the carrier frequency, which also increases the average applied power and the penetration factor. Master and carrier oscillators of the pulse generator operate asynchronously and digital mixer (20) is provided for combination of these frequencies. By combination of high and low-pass filter (24) and (26), the envelope of the pulse train waveform is given an increasing amplitude from its initial value during a predetermined interval. A set of specially-designed pulse transformers (T1) and (T2) is provided to maintain the optimal pulse waveform shape when the tissue impedance changes, providing compensation via a reactive component.</p> |
