Modulation circuit device, modulation method and radio communication device

• US 7,251,462 B2
• Filed: 07/07/2004
• Issued: 07/31/2007
• Est. Priority Date: 07/08/2003
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Matsuura, Toru, Adachi, Hisashi, Udagawa, Masaharu
• Primary Examiner(s): NGUYEN, DUC M
• Application Number:
  US10/886,371
• Publication Number:
  US 20050008093A1
• Time in Patent Office: 1,119 Days
• Field of Search: 455/108, 455/110, 330/10, 330/149, 330/124.R
• US Class Current: 455/108
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence
• CPC Class Codes: H03F 1/0222 by using a signal derived from the input signal
• CPC Class Codes: H03F 1/025 by using a signal derived from the input signal
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 2200/372 Noise reduction and elimination in amplifier
• CPC Class Codes: H03F 2203/7239 the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers and shunting lines by one or more switch(es)
• CPC Class Codes: H04L 27/361 Modulation using a single or unspecified number of carriers, e.g. with separate stages of phase and amplitude modulation

Abstract

The amplitude modulator comprises: an angle modulator for angle-modulating a phase signal to be inputted; a waveform shaping means in which, (1) when the magnitude of an amplitude signal to be inputted becomes smaller than a first prescribed value, a waveform of the amplitude signal is shaped so that the magnitude of the amplitude signal of the portion which becomes small becomes the first prescribed value; and/or (2) the waveform shaping means in which, when the magnitude of the amplitude signal to be inputted becomes larger than the second prescribed value which is larger than the first prescribed value, the waveform of the amplitude signal is shaped so that the magnitude of the amplitude signal of the portion which becomes larger becomes the second prescribed value; and an amplitude modulator for amplitude modulating the signal of the output of the angle modulator by the signal of the output of the waveform shaping means.

Claims

1. A modulation circuit device, comprising:

an angle modulator of angle-modulating a phase signal to be inputted;

a waveform shaping means in which, (1) when the magnitude of an amplitude signal to be inputted becomes smaller than a first prescribed value, a waveform of said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes small becomes said first prescribed value, and/or (2) when the magnitude of said amplitude signal to be inputted becomes larger than said second prescribed value which is larger than said first prescribed value, the waveform of said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes larger becomes said second prescribed value;

a direct current voltage supply circuit of supplying a direct current voltage;

a first amplitude modulator which operates on either of the operation modes of a first operation mode for amplifying the signal from the output of said angle modulator and a second operation mode for amplitude modulating the signal of the output of said angle modulator by the signal of the output of said waveform shaping means; and

a second amplitude modulator which operates on either of the operation modes of a first operation mode for amplifying the output of said first amplitude modulator and a second operation mode for amplitude-modulating the signal of the output of said first amplitude modulator by the signal of the output of said waveform shaping means;

wherein, when an output is made larger than a prescribed value by an output power, said first amplitude modulator is operated on said first operation mode with the signal from the output of said direct current voltage supply circuit controlled to be inputted, and said second amplitude modulator is operated on the second operation mode with the signal of the output of said waveform shaping means controlled to be inputted,

wherein, when an output is made by an output power smaller than a prescribed value, said first amplitude modulator is operated on said second operation mode with the signal from the output of said waveform shaping means controlled to be inputted, and said second amplitude modulator is operated on the first operation mode with the signal of the output of said direct current voltage supply circuit controlled to be inputted.

3. The modulation circuit device according to claim 1 or 2, wherein said voltage control circuit changes said direct current according the magnitude of an output power.

4. The modulation circuit device according to claim 1 or 2, wherein said waveform shaping means comprises:

amplitude control means of shaping the waveform of said amplitude signal; and

a voltage control circuit of generating an output signal based on the signal of the output of said amplitude control means.

5. The modulation circuit device according to claim 4, wherein a diode is used for said amplitude control means.

6. The modulation circuit device according to claim 4, wherein a series regulator is used for said voltage control circuit.

7. The modulation circuit device according to claim 4, wherein a switching regulator is used for said voltage control circuit.

8. The modulation circuit device according to claim 4, wherein said voltage control circuit serves as said amplitude control means,

wherein said voltage control circuit comprises a function to shape the waveform of said amplitude signal so as to meet the characteristic of said amplitude modulator.

9. The modulation circuit device according to claim 1 or 2, wherein said waveform shaping means comprises:

a voltage control circuit of amplifying said amplitude signal to be inputted; and

amplitude control means of shaping the waveform of the signal of the output of said voltage control circuit.

10. The modulation circuit device according to claim 9, wherein a diode is used for said amplitude control means.

11. The modulation circuit device according to claim 9, wherein a series regulator is used for said voltage control circuit.

12. The modulation circuit device according to claim 9, wherein a switching regulator is used for said voltage control circuit.

13. The modulation circuit device according to claim 9, wherein said voltage control circuit serves as said amplitude control means,

wherein said voltage control circuit comprises a function to shape the waveform of said amplitude signal so as to meet the characteristic of said amplitude modulator.

14. The modulation circuit device according to claim 1 or 2, (1) wherein the waveform shaping means shapes to round out an intersecting point with a portion which is cut and shaped by said first prescribed value and a portion which is not cut nor shaped by said first prescribed value from among said amplitude signals to be inputted, (2) and/or wherein the waveform shaping means and shapes to round out an intersecting point with a portion which is cut and shaped by said second prescribed value and a portion which is not cut nor shaped by said second prescribed value from among said amplitude signals to be inputted.

15. The modulation circuit device according to claim 14, wherein (1) from among the magnitude of said amplitude signals to be inputted, said waveform shaping means makes said intersecting point round and shaped so that the first order differential coefficient and the second order differential coefficient involved with the magnitude of said amplitude signals to be inputted of the magnitude of said signal from the output of said waveform shaping means corresponding to the portion made round and shaped of the side relating to said first prescribed value does not become negative, respectively, and/or wherein(2), from among the magnitude of said amplitude signals to be inputted, said waveform shaping means makes said intersecting point round and shaped, so that the first order differential coefficient involved with the magnitude of said amplitude signals to be inputted of the magnitude of said signal of the output of said waveform shaping means corresponding to the portion to be made round and shaped relating to said second prescribed value does not become negative nor the second order differential coefficient becomes positive.

16. The modulation circuit device according to claim 14, wherein said waveform shaping means shapes the waveform of said amplitude signal to be inputted by using a table which allows the input signal to correspond to the output signal.

17. A radio communication device, comprising:

a transmission circuit of outputting a transmission signal; and

a receiving circuit of inputting a receiving signal, wherein the modulation circuit device according to claim 1 or 2 is used for said transmission circuit.

20. The modulation method according to claim 18 or 19, (1) wherein the waveform shaping step makes round and shapes an intersecting point with a portion which is cut and shaped by said first prescribed value and a portion which is not cut nor shaped by said first prescribed value from among said amplitude signals to be inputted, (2) and/or wherein the waveform shaping step makes round and shapes an intersecting point with a portion which is cut and shaped by said second prescribed value and a portion which is not cut nor shaped by said second prescribed value from among said amplitude signals to be inputted.

21. The modulation method according to claim 20, wherein

(1) from among the magnitude of said amplitude signals to be inputted, said waveform shaping step makes said intersecting point round and shaped so that the first order differential coefficient and the second order differential coefficient involved with the magnitude of said amplitude signals to be inputted of the magnitude of said signal from the output of said waveform shaping means corresponding to the portion made round and shaped of the side related to said first prescribed value does not become negative, respectively, and/or wherein (2), from the magnitude of among said amplitude signals to be inputted, said waveform shaping means makes said intersecting point round and shaped, so that the first order differential coefficient involved with the magnitude of said amplitude signals to be inputted of the magnitude of said signal of the output of said waveform shaping means corresponding to the portion to be made round and shaped related to said second prescribed value does not become negative and the second order differential coefficient does not become positive.

2. A modulation circuit device, comprising:

an angle modulator of angle-modulating a phase signal to be inputted;

waveform shaping means in which, (1) when the magnitude of an amplitude signal to be inputted becomes smaller than a first prescribed value, a waveform of said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes small becomes said first prescribed value, and/or (2) when the magnitude of said amplitude signal to be inputted becomes larger than said first prescribed value which is larger than said second prescribed value, the waveform of said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes larger becomes said second prescribed threshold value;

a direct current voltage supply circuit of supplying a direct current voltage;

a first amplitude modulator which operates on either of the operation modes of a first operation mode for amplifying the signal from the output of said angle modulator and a second operation mode for amplitude-modulating the signal of the output of said angle modulator by the signal of the output of said waveform shaping means; and

a second amplitude modulator of amplitude-modulating the signal of the output of said first amplitude modulator by the signal of the output of said waveform shaping means;

wherein, when an output is made larger than a prescribed value by an output power, said first amplitude modulator is operated on said first operation mode with the signal from the output of said direct current voltage supply circuit controlled to be inputted, and said second amplitude-modulator amplitude modulates the signal of the output of said first amplitude modulator by the signal of the output of said waveform shaping means with the signal of the output of said waveform shaping means controlled to be inputted, and the signal of the output of said second amplitude modulator is outputted outside,

wherein, when an output is made smaller than a prescribed value by an output power, said first amplitude modulator is operated on the second operation mode with the signal from the output of said waveform shaping means controlled to be inputted, and the signal of the output of said first amplitude modulator is outputted outside.

18. A modulation method, comprising:

an angle modulation step of angle modulating a phase signal to be inputted by an angle modulator,

a waveform shaping step, in which (1), when the magnitude of an amplitude signal to be inputted becomes smaller than the first prescribed value, the waveform of said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes small becomes said first prescribed value, (2) and/or when the magnitude of said amplitude signal to be inputted becomes larger than a second prescribed value which is larger than a first prescribed value, the waveform of the said amplitude signal is shaped so that the magnitude of said amplitude signal of the portion which becomes large becomes said second prescribed value;

a direct current voltage supply step of supplying a direct current voltage by a direct current voltage supply circuit;

a first amplitude modulation step which operates a first amplitude modulator on either of the operation modes of a first operation mode for amplifying the signal from the output of said angle modulator or a second operation mode for amplitude modulating the signal of the output of said angle modulator by the signal of the output of said waveform shaping means; and

a second amplitude modulation step which operates a second amplitude modulator on either of the operation modes of a first operation mode for amplifying the signal from the output of said first amplitude modulator or a second operation mode for amplitude modulating the signal of the output of said first amplitude modulator by the signal of the output of said waveform shaping means;

wherein, when an output is made larger than a prescribed value by an output power, said first amplitude modulator is operated on said first operation mode with the signal from the output of said direct current voltage supply circuit controlled to be inputted, and said second amplitude modulator is operated on the second operation mode with the signal of the output of said waveform shaping means controlled to be inputted,

wherein, when an output is made smaller than a prescribed value by an output power, said first amplitude modulator is operated on said second operation mode with the signal from the output of said waveform shaping means controlled to be inputted, and said second amplitude modulator is operated on the first operation mode with the signal of the output of said direct current voltage supply circuit controlled to be inputted.

19. A modulation method, comprising:

an angle modulation step of angle-modulating a phase signal to be inputted by an angle modulator;

a waveform shaping step, in which, (1) when the magnitude of an amplitude signal to be inputted becomes smaller than said first prescribed value, the waveform of said amplitude signal is shaped by the waveform shaping means so that the magnitude of said amplitude signal of the portion which becomes small becomes said first prescribed value, (2) and/or, when the magnitude of said amplitude signal to be inputted becomes larger than a second prescribed value which is larger than a first prescribed value, the waveform of said amplitude signal is shaped shaping so that said amplitude signal of the portion which becomes large becomes said second prescribed value;

a direct current voltage supply step of supplying a direct current voltage by a direct current supply circuit;

a first amplitude modulation step which operates a first amplitude modulator on either of the operation modes of a first operation mode for amplifying the signal from the output of said angle modulator or a second operation mode for amplitude modulating the signal of the output of said waveform shaping means by the signal of the output of said waveform shaping means; and

a second amplitude modulation step which causes a second amplitude modulator to amplitude modulate the signal of the output of said first amplitude modulator by the signal of the output of said waveform shaping means,

wherein, when an output is made larger than a prescribed value by an output power, said first amplitude modulator is operated on said first operation mode with the signal from the output of said direct current voltage supply circuit controlled to be inputted, and said second amplitude modulator is controlled to be inputted with the signal of the output of said waveform shaping means, so that the signal from the output of said first amplitude modulator is amplitude-modulated by the signal of the output of said waveform shaping means, and the signal of the output of said second amplitude modulator is outputted outside,

wherein, when an output is made smaller than a prescribed value by an output power, said first amplitude modulator is operated on said second operation mode with the signal from the output of said waveform shaping means controlled to be inputted, and the signal of the output of said first amplitude modulator is outputted outside.