TRANSMITTER UNIT BY DIRECT CONVERSION METHOD

Title:

TRANSMITTER UNIT BY DIRECT CONVERSION METHOD

Document Type and Number:

Japanese Patent JP2008227708

Kind Code:

A

Abstract:

To adjust the IQ-signal amplitude balance of a transmitter unit by a direct conversion method, using a simple configuration.

A control voltage Ec of a main variable gain amplifier 66 is supervised. The amplitude values of IQ-signals, at both the output end of an orthogonal modulator 2 and a transmission output terminal 92 become identical, by adjusting the amplitude of the IQ-signal respectively by means of a first variable gain amplifier 26 and a second variable gain amplifier 28 so that the value of the control voltage Ec, when only the I-signal is output has an identical value to the control voltage Ec, when the Q-signal is output; in other words, the gain of the main variable gain amplifier 66 when amplifying only the I-signal has an identical value to the gain thereof, when amplifying only the Q-signal; and as a result, accurate IQ amplitude balance adjustment can be performed simply.

Inventors:

HIRABAYASHI KAZUO
NEMOTO HISAHIRO

Application Number:

JP2007060113A

Publication Date:

September 25, 2008

Filing Date:

March 09, 2007

Export Citation:

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Assignee:

JAPAN RADIO CO LTD

International Classes:

H04B1/04; H03C5/00; H03G3/20; H03G3/30; H04L27/00

Attorney, Agent or Firm:

Takehiro Chiba
Toshiyuki Miyadera
Naoki Kashima
Yasuo Takubo

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