CPC H03F 1/304 (2013.01) [G06F 30/367 (2020.01); H03F 1/0227 (2013.01); H03F 3/195 (2013.01); H03F 3/245 (2013.01); G06F 2119/06 (2020.01); G06F 2119/10 (2020.01); H03F 2200/102 (2013.01); H03F 2200/504 (2013.01); H03F 2201/3227 (2013.01)] | 20 Claims |
1. An envelope tracking system comprising:
a modulator configured to generate a radio frequency signal based on a digital transmit signal, the radio frequency signal having a signal envelope;
a supply voltage filter configured to filter a power amplifier supply voltage having a voltage level that changes in relation to the signal envelope;
a power amplifier configured to amplify the radio frequency signal, and to receive power from the power amplifier supply voltage;
a shaping circuit configured to generate shaped envelope data based on a digital representation of the signal envelope; and
a digital modeling circuit operable to receive the shaped envelope data, and to compensate the digital transmit signal for distortion arising from the supply voltage filter.
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