Title:
TRANSMITTER
Document Type and Number:
Japanese Patent JP3707549
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To carry out an ideal nonlinear distortion compensation by excluding incompleteness of amplitude delay characteristics or an influence of an intrinsic deviation that an amplifier has.
SOLUTION: A nonlinear distortion compensation coefficient operating part 18 estimates linear distortion characteristics caused by incompleteness of an analog circuit mainly such as a quadrature modulator 13 or a high output amplifier 14 based upon quadrature demodulated signals I'ch and Q'ch and calculates out a linear distortion compensation coefficient for compensating the linear distortion. A linear distortion compensation processing part 12 performs a predistortion (addition of inverse characteristics of linear distortion characteristics) by adding the linear distortion compensation coefficient to baseband signals Ich and Qch.
More Like This:
Inventors:
Yuzo Kurokami
Application Number:
JP2002080790A
Publication Date:
October 19, 2005
Filing Date:
March 22, 2002
Export Citation:
Assignee:
NEC
International Classes:
H03F1/32; H04B7/005; H04L27/36; (IPC1-7): H04L27/36; H04B7/005
Domestic Patent References:
| JP2002077285A | ||||
| JP964932A | ||||
| JP621990A | ||||
| JP2000299652A | ||||
| JP200116283A | ||||
| JP2001333124A | ||||
| JP7202955A |
Attorney, Agent or Firm:
Akio Miyazaki
Shinichi Iwata
Masaaki Ogata
Ishibashi Masayuki
Shinichi Iwata
Masaaki Ogata
Ishibashi Masayuki