Radio communication apparatus in which output power is controlled by pulse width modulation using a mobile attenuation code

• US 5,604,924 A
• Filed: 05/03/1994
• Issued: 02/18/1997
• Est. Priority Date: 05/25/1993
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yokoya, Satoshi
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): SOBUTKA, PHILIP
• Application Number:
  US08/237,151
• Time in Patent Office: 1,022 Days
• Field of Search: 455/126, 455/127, 455/70, 455/115, 455/116, 455/67.1, 455/92, 455/38.3, 455/68, 455/69, 330/278, 330/279, 330/297
• US Class Current: 455/68
• CPC Class Codes: H03F 1/0238 using supply converters
• CPC Class Codes: H03G 3/004 Control by varying the supply voltage
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04
• CPC Class Codes: H04B 1/40 Circuits

Abstract

A radio communication apparatus capable of varying the level of its transmission output, includes a receiving circuit, a transmitting circuit, an amplifier, an extractor, a detector, a variable voltage converter and a control circuit. The receiving circuit receives a signal from a second station such as a base station, and the transmitting circuit transmits a signal to the second station. The amplifier amplifies the output signal obtained from the transmitter, and the extractor extracts data from the output signal of the receiving circuit so as to control the level of the transmission output. The detector detects the level of the transmission output obtained from the amplifier, and the variable voltage converter converts a source voltage into the operating voltage of the amplifier. The control circuit produces a control signal to control the magnitude of the operating voltage supplied from the variable voltage converter to the amplifier in response to both the detection signal from the detector and the output signal from the extractor, and supplies the produced control signal to the variable voltage converter. The transmission output obtained from the amplifier is varied by changing the operating voltage supplied from the variable voltage converter to the amplifier.

Claims

1. A radio communication apparatus capable of varying the magnitude of its transmission output comprising:

a transmitting circuit for forming a transmission signal;

a receiving circuit for receiving from a base station a signal including a mobile attenuation code;

an amplifier for amplifying the transmission signal obtained from said transmitting circuit;

a variable voltage converter for converting a source voltage into an operating voltage of said amplifier; and

means for controlling said variable voltage converter, so that a magnitude of the operating voltage supplied from said variable voltage converter to said amplifier is varied in conformity to a magnitude of the transmission signal, wherein said means for controlling comprises;

a detector for detecting the magnitude of the transmission signal;

a comparator for comparing a detection signal from said detector with a value corresponding to the mobile attenuation code from said receiving circuit,

wherein an output of said comparator is supplied to said variable voltage converter as a control signal for a pulse width modulator included in said variable voltage converter and a pulse width modulated signal output from said pulse width modulator is integrated to form said operating voltage of said amplifier;

a sawtooth waveform reference signal generator for generating a sawtooth waveform reference signal; and

an adder for adding an output signal of said comparator to the reference signal obtained from said reference signal generator,

wherein an output signal of said adder is supplied to control said pulse width modulator included in said variable voltage converter.

2. The radio communication apparatus according to claim 1, wherein a gain of said amplifier is controlled in response to a change in magnitude of the transmission signal.

3. A radio communication apparatus comprising:

a receiving circuit for receiving a signal from a base station, wherein the signal includes a mobile attenuation code;

a transmitting circuit for transmitting a transmission output signal to said base station;

an amplifier for amplifying the transmission output signal of said transmitting circuit;

an extractor for extracting said mobile attenuation code from an output signal of said receiving circuit so as to control a level of the transmission output signal;

a detector for detecting a level of an output signal obtained from said amplifier;

a variable voltage converter for converting a source voltage into an operating voltage of said amplifier, wherein the operating voltage is varied in response to a control signal fed to said variable voltage converter; and

a control circuit including a comparator for comparing an output signal from said extractor and a detection signal from said detector for producing said control signal supplied to a pulse width modulator included in said variable voltage converter to control a magnitude of the operating voltage supplied to said amplifier,

wherein said control circuit further includes a sawtooth waveform reference signal generator for generating a sawtooth waveform reference signal, and an adder for adding an output signal of said comparator to the reference signal obtained form said reference signal generator, wherein an output signal of said adder is supplied to control said pulse width modulator included in said variable voltage converter.

4. The radio communication apparatus according to claim 3, wherein said control circuit supplies an output signal of said comparator to said amplifier so as to control a gain of said amplifier.

5. The radio communication apparatus according to claim 3, wherein said amplifier further includes an attenuator in a first stage thereof, and said control circuit supplies the output signal of said comparator to said attenuator so as to lower the level of the transmission output signal from said transmitting circuit.

6. The radio communication apparatus according to claim 3, wherein said amplifier consists of a first amplifier and a second amplifier connected to a last stage of said first amplifier;

and said first and second amplifiers are supplied with the operating voltage obtained from said variable voltage converter.