| 摘要 |
In order to minimize the adverse effects of RF signal nonlinearities duri ng amplification, especially the deleterious effects of signal clipping which m ay cause uncontrolled out-of-band emissions known as "spectral regrowth", the specification relates to a device and a method for intentionally distorting a radio frequency (RF) signal in a "tailored manner", prior to the amplification of the RF signal. The device monitors the amplitude of a RF signal at the inlet of a "tailored" distorter. A modifying signal waveform is generated whenever the amplitude of the monitored RF signal is greater than a threshold value. The RF signal is delayed to account for signal processing time associated with the generation of the modifying signal waveform. The generat ed modifying signal waveform is then summed with the delayed RF signal, thereby forming an intentionally distorted version of the original RF signal. The distorted signal is conveyed to a RF signal amplifier for amplification. The modifying waveform is chosen so as to reduce the amplitude of the RF signal peak to a value that does not exceed the clipping threshold. Furthermore, the modifying waveform is chosen ("tailored ") to be less harmful than the effects of the clipping distortion it replaces. The modifying waveform may be completely in-band, out-of-band, or have components of each, depending upon the specific implementation and the desired power spectrum. T he process is compatible with current predistortion techniques and may used in conjunction with, or in lieu, of signal predistortion.
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