US 10,873,301 B2 · Dual-input voltage memory digital pre-distortion circuit and related envelope tracking apparatus

Abstract

A dual-input voltage memory digital pre-distortion (mDPD) circuit and related ET apparatus are provided. In examples discussed herein, an ET apparatus includes an amplifier circuit(s) configured to amplify a radio frequency (RF) signal based on an ET voltage. A tracker circuit is configured to generate the ET voltage based on a number of target voltage amplitudes derived from a number of signal amplitudes of the RF signal. However, the tracker circuit can cause the ET voltage to deviate from the target voltage amplitudes due to various inherent impedance variations, particularly at a higher modulation bandwidth. In this regard, a dual-input voltage mDPD circuit is configured to digitally pre-distort the target voltage amplitudes based on the signal amplitudes such that the ET voltage can closely track the target voltage amplitudes. As such, it is possible to mitigate ET voltage deviation, thus helping to improve overall linearity performance of the ET apparatus.

Claims20

Dependent claims

A dual-input voltage memory digital pre-distortion (mDPD) circuit comprising:

a first port coupled to an input node of an envelope tracking (ET) engine circuit to receive a first digital signal having a plurality of signal amplitudes;
a second port coupled to an output node of the ET engine circuit to receive a second digital signal having a plurality of voltage amplitudes corresponding to the plurality of signal amplitudes;
and
a control circuit configured to:
receive the first digital signal and the second digital signal from the first port and the second port, respectively;
and
digitally pre-distort the plurality of voltage amplitudes based on the plurality of signal amplitudes to generate a digital target voltage signal having a plurality of target voltage amplitudes corresponding to the plurality of voltage amplitudes.

4 more elements

An envelope tracking (ET) apparatus comprising:

an ET engine circuit comprising:
an input node configured to receive a first digital signal having a plurality of signal amplitudes;
and
an output node configured to output a second digital signal having a plurality of voltage amplitudes corresponding to the plurality of signal amplitudes;
and
a dual-input voltage memory digital pre-distortion (mDPD) circuit comprising:
a first port coupled to the input node of the ET engine circuit to receive the first digital signal having the plurality of signal amplitudes;
a second port coupled to the output node of the ET engine circuit to receive the second digital signal having the plurality of voltage amplitudes;
and
a control circuit configured to:
receive the first digital signal and the second digital signal from the first port and the second port, respectively;
and
digitally pre-distort the plurality of voltage amplitudes based on the plurality of signal amplitudes to generate a digital target voltage signal having a plurality of target voltage amplitudes corresponding to the plurality of voltage amplitudes.

10 more elements

Dependencies are inferred from the claim text.

Dual-input voltage memory digital pre-distortion circuit and related envelope tracking apparatus

Life of this patent

Dual-input voltage memory digital pre-distortion circuit and related envelope tracking apparatus

Life of this patent

Abstract

Claims20