Transmitter

• US 20050136854A1
• Filed: 12/01/2004
• Published: 06/23/2005
• Est. Priority Date: 12/04/2003
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Tanaka, Koichiro, Tanabe, Mitsuru, Akizuki, Taiji
• Application Number:
  US11/001,809
• Publication Number:
  US 20050136854A1
• Time in Patent Office: Days
• US Class Current: 455/91
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only

Abstract

In a range (R3) in which an amplitude component voltage (VA) of a modulation wave signal from an OFDM signal generation unit corresponds to the average output power, an output voltage of a first voltage conversion unit (voltage applied to a base or a gate) is fixed, thus allowing the class AB operation of a high-frequency power amplifier. In a range (R4) in which VA is larger than that in R3, the output voltage of the first voltage conversion unit is increased, thus varying the operating class of the high-frequency power amplifier from class AB to class A. In a range (R2) in which VA is smaller than that in R3, the output voltage of the first voltage conversion unit is decreased, thus varying the operating class of the high-frequency power amplifier from class AB to class B. The efficiency at the time of the average power can be improved without degrading the maximum output power of the high-frequency power amplifier included in a transmitter.

Claims

1. A transmitter, comprising:

a modulation wave signal generation unit that generates a modulation wave signal;

a phase/amplitude separation unit that separates the modulation wave signal generated by the modulation wave signal generation unit into a phase component and an amplitude component;

a first voltage conversion unit that outputs a predetermined voltage with respect to the amplitude component and varies the output voltage from a minimum value to a maximum value in accordance with a variation of the amplitude component from a minimum value to a maximum value;

a second voltage conversion unit that outputs a predetermined voltage with respect to the voltage output from the first voltage conversion unit;

a frequency conversion unit that converts the phase component output from the phase/amplitude separation unit into a frequency to be transmitted; and

a high-frequency power amplifier, in which an output signal of the frequency conversion unit is supplied to a high-frequency input terminal, the output voltage of the first voltage conversion unit is applied to a base terminal or a gate terminal, and the output voltage of the second voltage conversion unit is applied to a collector terminal or a drain terminal, the high-frequency power amplifier outputting a modulated wave in which an amplitude and a phase are multiplied with each other.

2. The transmitter according to claim 1, wherein the first voltage conversion unit judges in what voltage range among a plurality of predetermined voltage ranges the amplitude component is included, and selects to output a predetermined constant voltage as a voltage level to be output for each of the plurality of predetermined voltage ranges or to perform a predetermined voltage level conversion between input and output voltages and output the result.

3. The transmitter according to claim 1, further comprising:

a unit for designating an output power level for the modulation wave signal generation unit.

4. A transmitter, comprising:

a modulation wave signal generation unit that generates a modulation wave signal;

an amplitude component generation unit that generates an amplitude component from the modulation wave signal generated by the modulation wave signal generation unit;

a first voltage conversion unit that outputs a predetermined voltage with respect to the amplitude component and varies the output voltage from a minimum value to a maximum value in accordance with a variation of the amplitude component from a minimum value to a maximum value;

a second voltage conversion unit that outputs a predetermined voltage with respect to the voltage output from the first voltage conversion unit;

a frequency conversion unit that converts the modulation wave signal output from the modulation wave signal generation unit into a frequency to be transmitted; and

a high-frequency power amplifier, in which an output signal of the frequency conversion unit is supplied to a high-frequency input terminal, the output voltage of the first voltage conversion unit is applied to a base terminal or a gate terminal, and the output voltage of the second voltage conversion unit is applied to a collector terminal or a drain terminal, the high-frequency power amplifier outputting a modulated wave in which an amplitude and a phase are multiplied with each other.

5. The transmitter according to claim 4, wherein the first voltage conversion unit judges in what voltage range among a plurality of predetermined voltage ranges the amplitude component is included, and selects to output a predetermined constant voltage as a voltage level to be output for each of the plurality of predetermined voltage ranges or to perform a predetermined voltage level conversion between input and output voltages and output the result.

6. The transmitter according to claim 4, further comprising:

a unit for designating an output power level for the modulation wave signal generation unit.