Device and method of pre-distorsion for compensating power amplifier

A power amplifier, predistortion circuit technology, applied in improving amplifiers to reduce nonlinear distortion, amplifiers, components of amplifying devices, etc. Linear characteristics, predistortion circuit can not compensate for memory effect, etc.

Inactive Publication Date: 2004-02-11
ERICSSON-LG
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0028] Since the input signal is simply precompensated by using compensation coefficients without considering the temperature change or frequency change of the input signal, the predistortion circuit cannot compensate for the memory effect according to the temperature change or frequency change of the input signal in the power amplifier. make accurate compensation
[0029] In addition, the signal input to the digital pre-distortion circuit in the normal mode is not a training signal covering the entire working area, so the compensation coefficient updated through the adaptation mode cannot accurately compensate the nonlinear characteristics of the power amplifier

Method used

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  • Device and method of pre-distorsion for compensating power amplifier
  • Device and method of pre-distorsion for compensating power amplifier
  • Device and method of pre-distorsion for compensating power amplifier

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Embodiment Construction

[0061] Figure 6 is a functional block diagram showing an example structure of an apparatus for compensating for predistortion of a power amplifier according to an embodiment of the present invention. The device includes a digital predistortion circuit 100, a digital-to-analog converter 200 and an upconverter 300 along one signal path. The device includes a downconverter 600, an analog-to-digital converter 700 and a digital predistortion circuit controller 800 along another signal path.

[0062] The digital pre-distortion circuit 100 pre-distorts an input digital signal (Vref) using a first compensation coefficient (Vcoef1) and a second compensation coefficient (Vcoef2). The digital-to-analog converter 200 converts the digital signal applied from the digital predistortion circuit 100 into an analog signal (Vda). And the up-converter 300 up-converts the baseband signal (Vda) from the digital-to-analog converter 200 to a radio frequency signal (Vdf).

[0063]The power amplifi...

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Abstract

An apparatus and method that compensates for pre-distortion of a power amplifier includes a digital pre-distorter controller which generates a power / phase compensation coefficient, a temperature compensation coefficient and a frequency compensation coefficient, a look-up table which stores the coefficients, a pre-distorter kernel which pre-compensates an input signal based on the temperature compensation coefficient from the look-up table, and a correction filter which compensates an output signal of the kernel based on the frequency compensation coefficient from the look-up table. If desired, an input signal may be pre-distorted based on only one of the temperature and frequency compensation coefficients along with the power / phase compensation coefficient. Nonlinear characteristics of the power amplifier are accurately checked and distortion due to the nonlinear characteristics are compensated for.

Description

technical field [0001] The present invention relates to amplifier circuits and, in particular, to apparatus and methods for compensating for distortion in power amplifiers. Background technique [0002] Compared with the analog mobile communication system, the digital mobile communication system has a wider signal bandwidth, which enables the digital mobile communication system to send more signals at a higher speed. In such systems, the signal is converted to a radio frequency (RF) signal and sent a certain distance. RF power amplifiers are used in the final transmission steps of mobile communication systems to enable transmission. [0003] In RF power amplifiers, one factor in amplifying each input signal with the same output amplification is linearity. Unfortunately, most power amplifiers do not have a wide linear range, so that amplified signals in regions outside the linear range are distorted and output, which is undesirable. [0004] Methods of improving the distor...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H03F1/32
CPCH03F1/3247
Inventor 金王来
Owner ERICSSON-LG
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