摘要 |
Embodiments provide systems and methods for producing an envelope tracking (ET) PA supply voltage with minimum headroom relative to the desired RF output signal of the PA. In an embodiment, the PA supply voltage is generated by applying an ET signal to an ET path of the wireless device, and by further applying pre-emphasis to the ET signal to compensate for a frequency response of the ET path. Embodiments operate by estimating the frequency response of the ET path and determining the pre-emphasis based on the estimate of the frequency response of the ET path. In embodiments, the pre-emphasis is applied using a pre-emphasis filter, which may be within or outside of the ET path. Further, the pre-emphasis may be applied to the ET signal in digital or analog form.
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