APPARATUS AND METHOD FOR CORRECTING NON-LINEAR DISTORTION BASED ON CHARACTERISTIC MODELING OF HIGH POWER AMPLIFIER

• US 20090219088A1
• Filed: 09/28/2006
• Published: 09/03/2009
• Est. Priority Date: 10/07/2005
• Status: Abandoned Application

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Park, Sung-Ik, Lee, Soo-In, Kim, Heung-Mook, Eum, Ho-Min, Seo, Jae-Hyun, Kim, Seung-Won, Lee, Yong-Tae
• Application Number:
  US12/089,475
• Publication Number:
  US 20090219088A1
• Time in Patent Office: Days
• US Class Current: 330/149
• CPC Class Codes: H03F 1/3241 using predistortion circuits H03F1/3211, H03F1/3217 take precedence
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0425 with linearisation using predistortion

Abstract

An apparatus for correcting a non-linear distortion includes a pre-distorter for pre-distorting a transmit signal inputted from an external apparatus based on pre-distortion characteristics outputted from a pre-distortion characteristic predictor; a modulator for modulating the pre-distorted signal to thereby generate a modulated signal; a frequency up-converter for up-converting a frequency of the modulated signal to thereby generate an up-converted signal; a high power amplifier for amplifying the up-converted signal to a high power amplified signal; a frequency down-converter for down-converting a frequency of the high power amplified signal, thereby generate a down-converted signal; a demodulator for demodulating the down-converted signal, to thereby generate a demodulated signal; a high power amplifying characteristic predictor for predicting characteristics of the high power amplifier based on the pre-distorted signal and the demodulated signal; and a pre-distortion characteristic predictor for predicting the pre-distortion characteristics based on the pre-distorted signal and the predicted high power amplifying characteristics.

Claims

1. An apparatus for correcting a non-linear distortion, comprising:

a pre-distorting means for pre-distorting a transmit signal inputted from an external apparatus based on pre-distortion characteristics outputted from a pre-distortion characteristic predicting means;

a modulating means for modulating the pre-distorted signal to thereby generate a modulated signal;

a frequency up-converting means for up-converting a frequency of the modulated signal to thereby generate an up-converted signal;

a high power amplifying means for amplifying the up-converted signal to a high power amplified signal;

a frequency down-converting means for down-converting a frequency of the high power amplified signal, thereby generate a down-converted signal;

a demodulating means for demodulating the down-converted signal, to thereby generate a demodulated signal;

a high power amplifying characteristic predicting means for predicting characteristics of the high power amplifying means based on the pre-distorted signal and the demodulated signal; and

a pre-distortion characteristic predicting means for predicting the pre-distortion characteristics based on the pre-distorted signal and the predicted high power amplifying characteristics.

2. The apparatus as recited in claim 1, wherein the high power amplifying characteristic predicting means obtains a characteristic model of the high power amplifying means and outputs the obtained characteristic model to the pre-distortion characteristic predicting means,

wherein the pre-distortion characteristic predicting means obtains an inverse characteristic function of the high power amplifying means based on the pre-distorted signal and the characteristic model of the high power amplifying means which is obtained by the high power amplifying characteristic predicting means.

3. A method for correcting a non-linear distortion, comprising the steps of:

a) at a high power amplifying characteristic predicting means, generating a characteristic model of a high power amplifying means by predicting characteristics of the high power amplifying means based on a pre-distorted signal which is outputted from a pre-distorting means and a demodulated signal which is outputted from a demodulating means;

b) at a pre-distortion characteristic predicting means, predicting pre-distortion characteristics based on the pre-distorted signal and the predicted characteristics model of the high power amplifying means; and

c) adapting the predicted pre-distortion characteristics to the pre-distorting means.

4. The method as recited in claim 3, wherein the pre-distortion characteristic predicting means obtains an inverse characteristic function of the high power amplifying means based on the pre-distorted signal and the characteristic model of the high power amplifying means which is obtained by the high power amplifying characteristic predicting means.

5. The method as recited in claim 3, further comprising the step of:

d) repeating the steps of a) to c) for chasing characteristics of a time variable system for a predetermined number of times.