Reduction of excessive spectral power distribution from class-C saturated amplification of a pulsed-carrier signal
US5789979A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1997 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Mar 18, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/217
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In an amplifier for amplifying a pulsed sinusoidal carrier signal, wherein the amplifier employs an amplifier element operative as Class-C with a saturation operation region which increases the sharpness of leading and trailing edges of a rectangular pulse envelope of the pulsed carrier signal for undesirable spectral spreading of energy of the signal, a method of reducing the spectral spreading of the energy employs a modification of the rectangular envelope of the pulsed carrier signal to a trapezoidal envelope. The leading and the trailing edges of the trapezoidal envelope constitute envelopes of sinusoidal waveforms of increasing and decreasing amplitude, respectively. The peak amplitudes of the largest amplitude sinusoidal of the leading and the trailing edges have powers which exceed a power level inducing the saturated operation of the amplifier element such that there is a decrement in incremental power gain by a factor of approximately 3 dB. In the pulse of carrier signal outputted by the amplifier element, the carrier in a central region thereof has a substantially square-wave configuration while, at the leading and the trailing edges, the cycles of the waveform are subst…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.