To provide a technique for shortening a convergence time of a distortion compensation coefficient.
A distortion compensation apparatus includes: a storing unit that stores the look-up table including distortion compensation coefficients for each address; a predistortion unit that selects addresses from the look-up table on the basis of an input signal, acquires distortion compensation coefficients stored at the selected addresses, and performs the predistortion of an input signal on the basis of the acquired coefficients; an error calculating unit that calculates an error with respect to the input signal from a feedback signal that indicates an output of a power amplifier; a coefficient calculating unit that calculates a plurality of new distortion coefficients from the error and the acquired distortion compensation coefficients by using the adaptive algorithm; a coefficient selecting unit that, for each of the selected addresses, selects a plurality of adequate coefficients from among a plurality of new distortion compensation coefficients based on the error; and a coefficient averaging unit that, for each of the addresses, calculates an average value of a plurality of adequate coefficients and replaces the distortion compensation coefficients with the average value.
ISHIKAWA HIROYOSHI
HAMADA HAJIME
UTSUNOMIYA YUICHI
HASE KAZUO
| JP2003198270A | 2003-07-11 | |||
| JP2002223171A | 2002-08-09 | |||
| JP2009218769A | 2009-09-24 |
| WO2008090613A1 | 2008-07-31 |
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