JPH10285059A - Level control circuit and communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the circuit design of the level control circuit and its manufacture. SOLUTION: When a designation section 41 designates designation reference transmission power among plural reference transmission power sets, an attenuation control section 42 sets the reference attenuation at first to a variable attenuation device 18, reads a reference signal level data signal denoting a predetermined reference signal level corresponding to the designated reference transmission power from a memory 45, compares a reference output data signal with a detection data signal denoting a DC voltage of an object signal through arithmetic processing and increases/decreases the reference attenuation within a reception and idle period in response to the comparison result. After the signal level of the object signal reaches a reference signal level and both the data signals are matched, a bias voltage control section 43 reads a reference bias voltage control data signal corresponding to the designated reference transmission power from the memory 45, converts the signal into an analog signal of the reference bias voltage and gives the resulting analog signal to an amplifier 19. Thus, the attenuation and the bias voltage are controlled through arithmetic processing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a level control circuit and a communication device which are suitably implemented for a cellular phone of a time division multiplex digital radio communication system.

[0002]

2. Description of the Related Art Conventionally, portable telephones change transmission power of electromagnetic waves in response to a transmission power change request given from a base station. As a prior art of a control circuit for controlling the transmission power, a transmission circuit of an analog cellular type mobile phone is disclosed in Japanese Patent Laid-Open No. 7-170202. An analog cellular type mobile phone uses a frequency modulation system as a signal modulation system, and simultaneously transmits and receives a target signal.

FIG. 5 is a block diagram showing an electrical configuration of the transmission circuit 1 described above. The signal level of the target signal which is an electric signal to be transmitted is different from the reference signal level at which the electromagnetic wave of the transmission power can be radiated from the antenna. The target signal is first attenuated by the variable attenuator 3 having a variable attenuation rate, and then the signal level is adjusted to the reference signal level by amplifying the bias voltage by the variable power amplifier 4. The target signal is
The power is supplied from the power amplifier 4 to the antenna 6 via the directional coupler 5, and transmitted from the antenna 6 as an electromagnetic wave.

In order to adjust the attenuation rate of the variable attenuator 3,
The detection circuit 7 detects and direct-current smoothes a part of the adjusted target signal provided via the directional coupler 5, detects a signal level of the target signal, and detects a detection voltage in response to the signal level. Is output. The comparator 8 compares the detection voltage from the detection circuit 7 with a predetermined reference voltage provided from the control circuit 9 and determines that the difference between the detection voltage and the reference voltage is zero.
The attenuation of the variable attenuator 3 is increased or decreased such that When such an analog negative feedback control operation is repeatedly performed, the attenuation of the variable attenuator 3 becomes a predetermined attenuation for setting the signal level of the target signal to the reference signal level. Further, in parallel with the above-described negative feedback control operation, the control circuit 9 calculates from the detection voltage from the detection circuit 7 and the reference voltage in order to reduce the current consumption of the power amplifier 4 and improve the power efficiency. The variable voltage power supply 10 is controlled using the control voltage thus obtained, and the power supply voltage and the bias voltage supplied from the variable voltage power supply 10 to the power amplifier 4 are changed.

In recent years, portable telephones using a time division multiplex digital radio communication system have been proposed. In the portable telephone, the same level control circuit as that of the conventional transmitter is used for transmission power control. Since the time-division multiplex digital radio communication system performs burst communication unlike the analog cellular system, it is determined in advance that an envelope of a signal waveform of an electromagnetic wave in the time becomes rectangular within an arbitrarily set time. It is necessary to output a target signal of a signal level. For this purpose, the control circuit 9 rapidly increases and decreases the reference voltage applied to the variable voltage power supply 10. Since the above-described level control circuit adjusts the attenuation rate by an analog negative feedback control operation, in order to operate following the rapid increase and decrease of the reference voltage, the operation speed of the detection circuit 7 and the comparator 8 must be controlled by the analog speed. It must be faster than when used in a cellular system.

[0006] The modulation method of the communication method is π / 4Q.
Since the digital signal is a linear digital modulation method such as the PSK method, data to be represented by the target signal is represented by using both the frequency component and the amplitude component of the target signal. Since the modulation system of the analog cellular system is a frequency modulation system, the above-described level control circuit works so as to always keep the amplitude component of the target signal at a predetermined amplitude. Therefore, if the operations of the detection circuit 7 and the comparator 8 are accelerated for the above-described reason, the level control circuit smoothes the amplitude change for representing data. For this reason, when the receiving mobile phone receives the target signal, the reproduced data is missing. Also, since the spectrum of the target signal is distorted, the adjacent channel leakage power increases,
The occupied bandwidth increases. Further, the modulation accuracy of the electromagnetic wave may be deteriorated.

For these reasons, when the above-described level control circuit is used for a time-division multiplex digital radio communication type portable telephone, the characteristics of each circuit in the level control circuit can follow the rapid increase and decrease of the reference voltage. It must be set strictly so that the amplitude change for representing the data of the target signal is not smoothed. These characteristics include the operating speed of the comparator 8 and the filter characteristics and time constant of the detection circuit 7. Since it is difficult to strictly determine the characteristics of each circuit at the time of circuit design and manufacture, the manufacture of the level control circuit becomes complicated and the manufacturing cost increases.

The above-described level control circuit changes the power supply voltage and the bias voltage of the power amplifier 4 while changing the attenuation rate by an analog negative feedback control operation. If this operation is performed while following a rapid increase and decrease of the reference voltage, the spectrum of the target signal is distorted, and the above-described problem occurs. Further, the line quality of the electromagnetic wave radiated from the antenna may be deteriorated.

Further, the above-described level control circuit is provided for the purpose of preventing a circuit handling a high-frequency signal from affecting other circuits and shortening a wiring length between circuits.
Since other circuits 3 to 5, 7, 9, and 10 other than the control circuit 9 need to be mounted on the same substrate, it is difficult to reduce the substrate area. In particular, the comparator 8 is realized by an operational amplifier or a comparator, and since the operational amplifier and the comparator are larger than other circuit components, it is more difficult to reduce the substrate area. Therefore, when this level control circuit is used, it is difficult to reduce the size of the mobile phone.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a communication device for transmitting and receiving a target signal in a time-division multiplexing system. An object of the present invention is to provide a level control circuit and a communication device to which a time division multiplexing method can be suitably applied.

[0011]

According to the present invention, there is provided a level control circuit for increasing or decreasing a predetermined signal level of a target signal to a predetermined reference signal level by a level changing means having a variable rate of change of the signal level. The signal level of the target signal output from the level changing means is compared with the reference signal level by arithmetic processing. When the signal level does not match the reference signal level, the rate of change of the level changing means is set to a predetermined ratio. A level control circuit characterized by further comprising a change rate control means for increasing or decreasing, and when the two signal levels match, maintaining the change rate. According to the present invention, the level control circuit previously stores the above-mentioned reference signal level and the above-mentioned ratio for increasing or decreasing the rate of change of the level changing means. Since the ratio control means determines the attenuation rate by the arithmetic processing, the comparator conventionally used for determining the attenuation rate can be realized by the arithmetic processing of the central processing circuit. Therefore, the comparator can be omitted from the level control circuit of the prior art. Further, the rate of change is increased or decreased by a predetermined ratio according to whether or not the signal level and the reference signal level match, so that it is not necessary to determine the ratio to be changed by following the signal level change of the target signal. Therefore, it is not necessary to set the processing speed of the ratio control means in response to the target signal. From these, the circuit design and manufacture of the level control circuit are facilitated.

According to the present invention, the signal level of a predetermined target signal is increased or reduced to a predetermined reference signal level by adjusting means including level changing means having a variable rate of change of the signal level and amplifying means having a variable bias voltage. In the level control circuit for reducing, the reference signal level is stored in association with a predetermined reference bias voltage for minimizing the current consumption of the amplification means when outputting the target signal of the reference signal level from the adjustment means. Comparing the signal level of the target signal output from the adjustment means with the reference signal level stored in the storage means, and when the signal level does not match the reference signal level, the level change is performed. The rate of change of the means is increased or decreased by a predetermined rate, and the rate of change is maintained when the two signal levels match. And control means, a level control circuit which comprises a bias voltage supply means for supplying the amplifying means the stored reference bias voltage to the storage means.
According to the present invention, the level control circuit adjusts the signal level of the target signal using the level changing means described in claim 1 and the amplifying means described above. As a result, the circuit design and manufacturing of the portion of the level control circuit related to the control of the rate of change of the level changing means can be simplified. Further, the bias voltage supply means includes:
A reference bias voltage capable of minimizing the current consumption of the amplifying means is stored in the storage means in advance, and the bias voltage is supplied as described above with reference to the storage contents of the storage means. Therefore, it is not necessary to determine the bias voltage sequentially in response to the time change of the rate of change of the level changing means. Therefore, the processing operation for controlling the bias voltage can be simplified. Therefore, it is possible to easily design and manufacture a part of the level control circuit for controlling the bias voltage. Further, since the operation of the bias voltage supply means can be realized by the arithmetic processing of the central processing circuit for performing the arithmetic processing of the change rate control means, the circuit configuration of the level control circuit can be further simplified. Furthermore, the level control circuit prepares a plurality of reference signal levels and a reference bias voltage corresponding to each reference signal level in advance, and designates one of the plurality of reference signal levels to be designated and designated. Using the reference signal level and the reference bias voltage corresponding to the reference signal level,
The above processing may be performed.

According to the present invention, there is provided a time-division multiplex communication apparatus in which a predetermined signal level of a target signal is adjusted to a predetermined reference signal level by adjusting means and transmitted by transmitting means. Is a communication device that adjusts the signal level of the target signal when not transmitting the target signal, and does not adjust the signal level of the target signal when transmitting the target signal. According to the present invention, the communication device is a communication device of the time division multiplex system, and the signal level of the target signal to be transmitted is adjusted by the transmission means when the communication device does not transmit the target signal, that is, when the other communication device The signal level adjustment is performed during a period in which the target signal is received and a period in which transmission and reception are not performed, and the signal level is not adjusted during the transmission period. Thus, it is possible to prevent the signal level of the signal to be transmitted from changing when transmitting. Therefore, it is possible to prevent spectrum distortion and spurious generation due to a signal level change from occurring in a signal to be transmitted.

According to the present invention, the signal level of a predetermined target signal is adjusted by adjusting means including a level changing means having a variable rate of change of the signal level and an amplifying means having a variable bias voltage. In a communication device which increases or decreases the signal level for transmitting the electromagnetic wave of the reference transmission power designated by the designation means in the communication device and transmits the electromagnetic wave, the reference transmission power and the reference transmission power are provided for each reference transmission power. A predetermined reference signal level for transmitting an electromagnetic wave of electric power, and a predetermined reference bias voltage for minimizing the current consumption of the amplifying means when transmitting the electromagnetic wave and for setting the line quality of the electromagnetic wave to a predetermined quality. , The signal level of the target signal output from the adjustment means, and the reference signal level stored in the storage means. And comparing the reference signal level corresponding to the reference transmission power designated by the designation means by arithmetic processing, and when the signal level does not match the reference signal level, the rate of change of the level change means is calculated. Change rate control means for increasing or decreasing by a predetermined ratio and maintaining the change rate when the two signals coincide with each other; and the reference transmission power designated by the designating means among all the reference bias voltages stored in the storage means. And a bias voltage supplying means for supplying a reference bias voltage corresponding to the above to the amplifying means. According to the present invention, the communication device controls the signal level of the target signal using the level control circuit according to claim 2. In this level control circuit, since the reference signal level and the reference bias voltage of the target signal are predetermined in response to the predetermined reference transmission power of the electromagnetic wave, the reference transmission power specified by the specifying means is changed. It is not necessary to follow the signal level change of the target signal each time the ratio and the bias voltage are determined. Therefore, thereby, claim 1
In the same manner as in (2) and (2), it is possible to easily design and manufacture a circuit for changing the rate of change of the level changing means and the bias voltage of the amplifying means in the communication device. In particular, conventionally, in a communication device of the time division multiplex radio communication system, it is necessary to strictly determine the characteristics of the comparator and the detection circuit, and circuit design and manufacturing have been complicated. In the communication device according to the fourth aspect, since the transmission power of the electromagnetic wave is controlled by the level control circuit according to the second aspect, the circuit design and manufacturing of the above-described portion are facilitated, the entire communication device is easily manufactured, and the manufacturing cost is reduced. Can be reduced. In addition, since the part can be realized by the arithmetic processing of the central processing circuit, the part can be easily integrated.
Therefore, the number of components of the communication device can be reduced, and the size and weight of the communication device can be reduced. Further, each time the reference transmission power specified by the specifying means is changed,
The bias voltage of the amplifier is controlled so that the current consumption of the amplifier is minimized. Among the above communication devices, the amplifier consumes a larger amount of current than other circuit components. Since the current consumption of the amplifying means is always minimized, the power consumption of the communication device can be reduced while maintaining the line quality of the electromagnetic wave. Therefore, when the same battery as the conventional communication device is used, the communication device according to claim 4 has a time from when a fully charged battery is attached to when the battery is replaced,
It can be longer than a conventional communication device. When the communication device of claim 4 is used as a communication device of the time division multiplex system, claim 3 may be further applied to claim 4.

[0015] The present invention further includes physical quantity detecting means for detecting a physical quantity that changes the characteristic of the bias voltage supplying means, wherein a plurality of the reference bias voltages are prepared corresponding to the physical quantities. A reference bias voltage corresponding to the reference transmission power designated by the designation means and corresponding to the physical quantity detected by the physical quantity detection means among all the reference bias voltages stored in the storage means, It is characterized by giving. According to the invention, the reference bias voltage is provided as described above in response to a physical quantity that can change the characteristics of the amplifying means. Thus, even when the physical quantity changes and the characteristics of the amplifier change, the current consumption of the amplifier can always be minimized. Further, since the reference bias voltage corresponding to the physical quantity is prepared in the storage means in advance, it is not necessary to determine the bias voltage sequentially in response to the time change of the physical quantity. Therefore, the processing operation for changing the bias voltage according to the physical quantity can be simplified.

In the present invention, the physical quantity is a temperature. According to the invention, the reference bias voltage is
Given as above in response to temperature. The amplification means
Since the circuit characteristics may change when the temperature changes, if the bias voltage of the amplifying unit is kept at a constant value at this time, the current consumption may change. The level control circuit according to the sixth aspect provides a reference bias voltage responsive to the temperature, so that the level control circuit can change the temperature even when the temperature changes.
By the same simple processing as described above, the current consumption of the amplification means can always be minimized.

The present invention further includes a reference power supply for supplying a predetermined voltage to the amplification means, and the physical quantity is a voltage of the reference power supply. According to the present invention,
The reference bias voltage is provided as described above in response to the voltage of the reference power supply. The power efficiency of the amplifying means is determined by the voltage from the reference power supply and the bias voltage. The voltage of the reference power supply may change depending on the temperature or the like. At this time, if the bias voltage of the amplifying unit is kept at a constant value, the current consumption may change. In the level control circuit according to the seventh aspect, by applying a reference bias voltage responsive to the voltage of the reference power supply, even when the voltage of the reference power supply changes, the current of the amplifying means is always changed by the same simple processing as in the fifth aspect. Consumption can be minimized.

According to the present invention, the bias voltage supply means includes:
When the change rate is increased or decreased by the change rate control means, a reference bias voltage corresponding to a maximum reference transmission power among the total reference signal levels stored in the storage means is provided to the amplification means, When the rate of change is maintained, a reference transmission power corresponding to a reference signal level designated by the designation means among all reference bias voltages stored in the storage means is provided to the amplification means. . According to the present invention, the communication device of claim 8 is:
Instead of the bias voltage supply means of claim 4, the bias voltage supply means of claim 8 is used. The bias voltage supply means applies a reference bias voltage corresponding to the maximum reference transmission power while the change rate is increased or decreased by the change rate control means. This allows, for example,
When the reference transmission power newly designated by the designation means is higher than the reference transmission power designated before the designation, the amplification means is saturated and the spectrum of the target signal is distorted, thereby deteriorating the line quality of the electromagnetic wave. Can be prevented.

[0019]

FIG. 1 is a block diagram showing an electric configuration of a communication device 11 according to a first embodiment of the present invention.
The communication device 11 is, for example, a time-division multiplex wireless communication type mobile phone. The communication device 11 includes an operation unit 13, a microphone 14, a baseband processing circuit 15, a high-frequency processing circuit 17, a variable attenuator 18, an amplifier 19, a reference power source 20,
It includes a power supply circuit 21, a directional coupler 22, an antenna 23, a speaker 25, a central processing circuit 26, a display unit 27, a vibrator 28, a detection circuit 31, a temperature sensor 33, and a memory 45. Among them, the variable attenuator 18, the amplifier 19,
The reference power supply 20, the power supply circuit 21, the directional coupler 22, the central processing circuit 26, the detection circuit 31, the temperature sensor 33, and the memory 45 constitute a level control circuit according to the present invention. In the drawing, the high frequency is represented as “RF”, and the baseband is represented as “B”.
B ".

When the operator of the communication device 11 performs communication from the communication device 11 to another communication device, the operator operates a key provided on the operation section 13 to input a telephone number and the like of the other communication device.
Voice is input from the microphone 14. The baseband processing circuit 15 performs a predetermined process determined in accordance with the communication method on an electric signal representing a voice given from the microphone 14, further adds a data signal related to an input telephone number and the like, and A band signal is generated and supplied to the high frequency processing circuit 17.

The high-frequency processing circuit 17 generates a target signal by modulating a carrier signal which is a high-frequency signal of a predetermined frequency by a baseband signal. The signal level of the target signal always keeps a predetermined level, for example. The target signal is first attenuated by a variable attenuator 18 whose signal level attenuation is variable, and further amplified by an amplifier 19. The gain of the amplifier 19 is always constant, for example,
The signal level of the target signal output from the amplifier 19 is proportional to the signal level of the target signal output from the variable attenuator 18. Thereby, the signal level of the target signal is adjusted to a reference signal level described later. As the power supply voltage of the amplifier 19, the voltage from the reference power supply 20 is
The signal is supplied via the power supply circuit 21 only when the electromagnetic wave is transmitted, and is supplied intermittently so as not to be supplied when the electromagnetic wave is not transmitted. The bias voltage of the amplifier 19 is given by a method described later, and its value is variable. Amplifier 1
After a part of the target signal output from 9 is extracted by the directional coupler 22, the signal is again supplied to the high frequency processing circuit 17, supplied to the antenna 23 from the high frequency processing circuit 17, and transmitted as an electromagnetic wave from the antenna 23. You. This electromagnetic wave is received by another communication device via the base station.

The target signal transmitted as an electromagnetic wave from another communication device is received by the antenna 23 via the base station. In some cases, a signal indicating an output power change request given from the base station to the communication device 11 is added to the target signal. After reception, the electromagnetic wave of the target signal is demodulated by the high-frequency processing circuit 17 to be a baseband signal, and the baseband processing circuit 15 performs a predetermined process corresponding to the communication method, thereby generating a voice. Is represented by an electrical signal. The electric signal is output as a sound from the speaker 25. After the signal indicating the output power change request is separated from the target signal by the baseband processing circuit 15, the signal is supplied from the baseband processing circuit 15 to the central processing circuit 26. The display unit 27 displays the operation result of the operation unit 13 and data related to the transmitted and received baseband signals. The vibrator 28 vibrates when the target signal from another communication device is first received, and notifies the operator of the arrival of the target signal.

The target signal extracted by the directional coupler 20 is supplied to a detection circuit 31. The detection circuit 31
The target signal is AM-detected and further smoothed, the signal level of the target signal is detected, and a detection signal representing the signal level of the target signal is generated. The detection signal is converted to a detection data signal, which is a digital signal, by an analog / digital conversion circuit 32 and then supplied to a central processing circuit 26. The temperature sensor 33 measures the air temperature in the space where the communication device 11 is placed, and outputs a measurement signal indicating the air temperature. The measurement signal of the temperature sensor 33 and the voltage value of the reference power supply 20 are provided to the central processing circuit 26 via analog / digital conversion circuits 34 and 35 individually.

The central processing circuit 26 includes a designation unit 41, an attenuation control unit 42, and a bias voltage control unit 43. The central processing circuit 26 is realized by, for example, a microcomputer, and each of the units 41 to 43 is a virtual circuit realized by arithmetic processing of the central processing circuit 26. Each part 41-
43 may be realized by individually independent circuit components.

[0025] In response to the output power change request, the specifying unit 41 specifies the reference transmission power specified by the base station by the output power change request, from among a plurality of predetermined reference transmission powers. The reference transmission power is transmission power of an electromagnetic wave transmitted from the communication device 11, and is defined in advance in response to a communication method using the communication device. For example, when the communication device 11 is a digital cellular type mobile phone in Japan, the reference transmission power is 0 dB, -4 dB, -8 dB, -12 dB.
B, -16 dB, and -20 dB, and the base station selects a reference transmission power with a larger output as the distance between the base station and the communication device 11 is longer. Data representing the power value of each reference transmission power is stored in the memory 45 in advance.

Each time the designating section 41 designates a new reference transmission power, the attenuation control section 42 and the detection data signal supplied from the analog / digital conversion circuit 32 and the memory 45
With reference to the reference signal level data signal stored in
An attenuation control data signal for controlling the attenuation of the variable attenuator 18 is set by a method described later. The reference signal level data signal is a digital signal representing a power value of a predetermined reference signal level, and is predetermined individually corresponding to each reference transmission power. The reference signal level corresponding to a certain reference transmission power is the signal level of the target signal output from the amplifier 19 when the antenna 23 transmits an electromagnetic wave of the reference transmission power. The attenuation control data signal is digital /
After being subjected to digital / analog conversion by the analog conversion circuit 47, it is provided to the variable attenuator 18. The variable attenuator 18
The amount of attenuation is set in response to the voltage of the output signal from the digital / analog conversion circuit 47.

The bias voltage controller 43 sets the temperature sensor 3 after the attenuation controller 42 sets the attenuation in the above-described manner.
With reference to the measurement signal No. 3 and the voltage of the reference power supply 20, a reference bias voltage control data signal for controlling the bias voltage of the amplifier 19 is read from the memory 45 by a method described later. The reference bias voltage control data signal is a control digital signal for outputting a predetermined reference bias voltage from the DC / DC conversion circuit 49, and is predetermined corresponding to each reference transmission power. The reference bias voltage corresponding to a certain reference transmission power is such that when the electromagnetic wave of the reference transmission power is transmitted from the antenna 23, the current consumption of the amplifier 19 is minimized and the line quality of the electromagnetic wave is minimized. It is. Further, a plurality of reference bias voltages corresponding to the respective reference transmission powers are prepared in advance corresponding to the temperature and the voltage of the reference power supply 20.
It is associated with a voltage of 0. The reference bias voltage control data signal is subjected to digital / analog conversion by the digital / analog conversion circuit 48 and then to a DC / DC conversion circuit 49.
Given to. The DC / DC converter 49 is a digital / DC converter.
The output signal from the analog conversion circuit 48 is increased or decreased at a predetermined rate of change to generate a bias voltage output signal, which is supplied to the amplifier 19.

The electromagnetic wave having the optimum line quality refers to an electromagnetic wave that satisfies the regulations defined by the Radio Law. For example, mobile phones meet the provisions of the Radio Law,
In addition, it is an electromagnetic wave that satisfies the provisions of the radio performance of transmission specified by the Radio Standards Compliance Law (RCR STD-27). Of the above provisions, in particular, the Radio Equipment Inspection and Certification Association (MK
It is preferable that all the requirements checked by the test for the certification of technical standards performed by K) are satisfied. Also,
When the communication device 11 is a time-division multiplex digital portable radio device, since the modulation system is the π / 4 shift DQPSK system, it is preferable to satisfy the regulation to be inspected by the test and the regulation for modulation accuracy. This regulation of modulation accuracy is satisfied when the modulation accuracy is 12.5% or less.

The memory 45 stores, for each reference transmission power, the reference signal level data signal, the reference bias voltage control data signal, and a predetermined reference attenuation control data signal in association with the reference transmission power. It is memorized. The reference attenuation control data signal is a control digital signal for setting a predetermined reference attenuation in the variable attenuator 18.
Each reference transmission power corresponds individually. The reference attenuation amount corresponding to a certain reference transmission power is an ideal value of the variable attenuator 18 when the signal level of the target signal output from the high-frequency processing circuit 17 is set to the reference signal level corresponding to the reference transmission power. It is the amount of attenuation.

For example, when the communication device 11 is manufactured in a factory, the reference signal level is caused to cause the communication device 11 to actually transmit the electromagnetic wave of each reference transmission power.
The signal level of the target signal output from is measured by using a measuring device such as a power meter and a tester. Similarly, each of the reference bias voltages is used for the communication device 11.
After the manufacture, the communication device 11 is caused to actually transmit the electromagnetic wave of each reference transmission power having the optimum line quality, and at the same time, the bias voltage is variously changed to measure the bias voltage when the current consumption of the amplifier 19 is minimized. Is obtained. The reference signal level and the reference bias voltage are different for each individual communication device due to, for example, variations in the characteristics of the circuit components of the communication device 11. Therefore, the reference signal levels and the reference bias voltages can be individually measured for each manufactured communication device 11. preferable.

FIG. 2 is a timing chart for explaining the operation timing of the power control operation of the communication device 11 of the time division multiplex digital system. FIG. 3 is a flowchart illustrating an initialization operation of the power control operation. FIG. 4 is a flowchart for explaining the transmission power control operation of the power control operation. By taking the operation timing of FIG. 2 as an example, FIG.
Will be described in detail. In the following description, it is assumed that the communication device 11 is a communication device of the time division multiplex digital wireless communication system. The time-division multiplex digital wireless communication system is used, for example, as a communication system for a digital cellular mobile phone in Japan.

In the time division multiplex digital radio communication system, a transmission operation for transmitting an electromagnetic wave and a reception operation for receiving an electromagnetic wave are alternately performed in a time division operation. Therefore, when communication is started, the communication device 11 performs a transmission operation, a measurement operation for measuring the reception electric field strength of an electromagnetic wave, a reception operation, and an idle operation for stopping both transmission and reception in this order with time. And these operations are periodically repeated. FIG.
Then, reference numeral T indicates a transmission period for performing a transmission operation, reference numeral LM indicates a measurement period for performing a measurement operation, reference numeral R indicates a reception period for performing a reception operation, and reference numeral I indicates a reference numeral for an idle period during which an idle operation is performed.
Is added. When the communication device 11 is a diversity communication device, the reception electric field strength of the electromagnetic wave measured during the measurement period LM is used to determine the switching of the antenna that receives the electromagnetic wave.

In the example shown in FIG. 2, the communication device 11
During an initial transmission period T1 starting from 0, an electromagnetic wave having a reference transmission power predetermined as an initial value among a plurality of reference transmission powers is transmitted. The base station receives the electromagnetic wave, determines a reference transmission output of the electromagnetic wave to be transmitted by the communication device 11 from the received electric field strength of the electromagnetic wave, and outputs an output power change request. This output power change request is received by the communication device 11 at time t1 in the first reception period R1.

Each time each of the reception periods R1 to Rn is started,
The central processing circuit 26 performs the initialization operation shown in FIG. The initialization operation proceeds from step a1 to step a2 when the antenna 23 and its attached parts are switched to a state in which electromagnetic waves can be received. In step a2, the designation unit 41
Determines whether the output power change request has been given from the baseband processing circuit 15. The determination in step a2 is
This is repeated until an output power change request is given. In the example of FIG. 2, since the output power change request is given at time t1 in the first reception period, the process proceeds to step a3 after time t1.

In step a3, first, the bias voltage control section 43 initializes a reference bias voltage control data signal. Specifically, for example, a reference bias voltage control data signal corresponding to the maximum reference transmission power among all reference transmission powers is read out from memory 45, and is supplied to DC / DC conversion circuit 49 via digital / analog conversion circuit 48. Give to. As a result, the DC / DC conversion circuit 49 gives the power amplification circuit 19 a reference bias voltage corresponding to the maximum reference transmission power.

Next, the specifying unit 41 specifies one of the reference transmission powers based on the output power change request. Hereinafter, the reference transmission power specified by the specifying unit 41 is referred to as a specified reference transmission power. The attenuation amount processing unit 42 reads out the reference attenuation amount control data signal corresponding to the designated reference transmission power from the memory 45, and provides the same to the variable attenuator 18 via the digital / analog conversion circuit 47. Thereby, the reference attenuation corresponding to the designated reference transmission power is set in the variable attenuator 18. Thereafter, the flow returns to step a2, and the operations of steps a2 and a3 are repeated until the reception periods R1 to Rn and the idle periods I1 to In following the reception period end.

In the example of FIG. 2, the processing operation of FIG.
At the end time t2 of the first idle period I1, the amplifier 1
A reference bias voltage corresponding to the maximum reference transmission power is given to 9, and a reference attenuation corresponding to the designated reference transmission power is set to the variable attenuator 18. The central processing circuit 26
When the processing in step a3 of the reception period processing operation is completed,
Next, the transmission power control operation of FIG. 4 is performed.

The transmission power control operation is started from the point in time when the transmission period is first started after the processing in step a3 of the initialization operation is completed, and from step b1 to step b
Proceed to 2. In step b2, first, the detection circuit 31 detects and smoothes the target signal at the time of transmitting the portion representing the predetermined data signal among the target signals output from the high-frequency processing circuit 17 during the transmission period. , A detection signal representing the signal level of the target signal at that time is generated.
The predetermined data signal is, for example, a sync word (S
W). The detection circuit 31 always generates a detection signal,
At this time, the central processing circuit 26 may acquire the detection signal via the analog / digital conversion circuit 32.

Next, the attenuation control unit 42 reads the reference signal level data signal corresponding to the designated reference transmission power from the memory 45 and compares it with the detection data signal at the time given from the analog / digital conversion circuit 32, It is determined whether they match. This comparison may determine whether or not the reference signal level data signal and the detected data signal completely match. Also, in order to take into account errors due to smoothing of the detection circuit 31 and errors such as quantization errors of the analog / digital conversion circuit 32, it is determined whether or not only the upper bits of both data signals match. You may. For example, when the reference signal level data signal and the detection data signal are both 8-bit digital signals, only the upper 5 bits are compared, and if the upper 5 bits match regardless of whether the lower 3 bits match, both signals are compared. It is determined that the data signals match. In addition, the upper limit value and the lower limit value of a predetermined range are stored in advance as a reference signal level data signal. You may. When the two data signals do not match, the process proceeds to step b3, and when they match, the process proceeds to step b4.

In the example shown in FIG. 2, when the detection data signal is acquired at time t3 of T2 in the second transmission period, it is immediately after the reference attenuation is set in the first reception and idle periods R1 and I1. And the reference signal level data signal do not match. At this time, the process proceeds to step b3.

In step b3, the attenuation control unit 42
By increasing or decreasing the current attenuation set in the variable attenuator 18,
Reset. For example, the detection data signal is compared with the reference signal level data signal, and when the signal level of the target signal is equal to or higher than the reference signal level, the current attenuation is reduced by a predetermined value. When the signal level of the target signal is lower than the reference signal level, the current attenuation is increased by a predetermined amount. Attenuation control unit 42
After the attenuation amount is determined to be decreased or increased from the comparison result of the two data signals, the currently output attenuation is represented so as to represent a new attenuation amount in which the current attenuation amount is decreased or increased by a predetermined amount. Rewrite the quantity control data signal. The rewritten attenuation control data is supplied to the digital / analog conversion circuit 4 in a reception period R immediately after the transmission period T in which the detection data signal is obtained and in an idle period I following the reception period R.
7 to a variable attenuator 18. Thereby, the new attenuation amount is set in the variable attenuator 18. After resetting the attenuation, the process returns to step b2. The processing operations in steps b2 and b3 are started each time each transmission period T is started until the detection data signal and the reference signal level data signal match.

In the example of FIG. 2, first, the second transmission period T
Based on the detection data signal acquired at time t3 in time t2, steps b2 and b3 are performed between time t3 and time t4 in the second reception period R2 and idle period I2.
The reference attenuation is increased or decreased by the processing operation of (1), and a new attenuation is set in the variable attenuator 18. Next, the amount of attenuation reset at time t4 is increased or decreased based on the detection data signal acquired at time t5 in the third transmission period T3, and the attenuation in the third reception period R3 and the idle period I is reduced. At the time, a new attenuation is set in the variable attenuator 18. By periodically resetting the attenuation of the variable attenuator 18 in this manner, the signal level of the target signal matches the reference signal level after a sufficient time has elapsed from the time t1 at which the output power change request was given. . In FIG. 2, n in the n-th transmission period Tn is an arbitrary integer.
It is assumed that the detected data signal obtained at time t11 matches the reference signal level data signal.

The attenuation controller 42 increases or decreases the current attenuation by a predetermined value. As a result, it is not necessary to determine the amount of increase or decrease of the attenuation amount sequentially according to the time change of the target signal. Therefore, the processing can be simplified as compared with the conventional technique of controlling the attenuation of the communication device. Further, since the reference attenuation corresponding to the reference transmission power is set in advance in the variable attenuator 18 by the above-described initialization operation, the attenuation before the output power change request is given as in the case of the communication device of the related art is calculated. The amount by which the amount of attenuation is increased or decreased is smaller than when changed by the analog negative feedback control operation. Therefore, the processing can be further simplified.

When the attenuation is reset, the predetermined amount may be weighted according to the number of repetitions of steps b2 and b3, and the smaller the number of repetitions, the greater the predetermined amount. For example, the predetermined amounts at the time of the first, second, and third resetting are set to three times the predetermined reference amount, twice the reference amount, and the reference amount, and the fourth and subsequent times are set. May always be a reference amount. Furthermore, the difference between the signal level of the target signal and the reference signal level and the amount of change in the amount of attenuation in response to the difference are stored in advance in the memory 45, and when the amount of attenuation is reset, the difference is set. The current attenuation may be calculated or increased or decreased by the amount of change in response to the difference. As a result, from time t1 to time t11
Can be shortened.

As described above, the amount of attenuation of the variable attenuator 18 is not changed in the transmission periods T1 to Tn, but in the reception periods R1 to Rn and the idle periods I1 to In immediately after the transmission periods T1 to Tn. Be changed. If the amount of attenuation of the variable attenuator 18 is changed during the transmission periods T1 to Tn, the signal level of the target signal output from the variable attenuator 18 changes with the passage of time. Also changes the transmission power. As a result, while the attenuation is changing, distortion and spuriousness may be generated in the electromagnetic wave due to the change in the transmission power. As described above, the attenuation of the variable attenuator 18 is changed to the reception periods R1 to Rn and the idle periods I1 to In, and the transmission periods T1 to
By maintaining the attenuation at a constant value for Tn, the above problem can be prevented.

In the example of FIG. 2, when the transmission power control operation is continued after time t11, the attenuation control unit 42 determines that both data signals match in step b2, and proceeds to step b4. In step b4, the bias voltage control unit 43 determines whether the designated reference transmission power is the maximum reference transmission power among all the reference transmission powers. When the designated reference transmission power is the maximum reference transmission power, since the reference bias voltage corresponding to the reference transmission power has already been given to the amplifier 19 by the initialization operation of FIG. The process returns from step b4 to step b2. When the designated reference transmission power is not the maximum reference transmission power, step b
Go to 5.

In step b5, the bias voltage control unit 4
3 first obtains the measurement signal from the temperature sensor 33 via the analog / digital conversion circuit 34 and further obtains the voltage of the reference power supply 20 via the analog / digital conversion circuit 35. Next, a reference bias voltage control data signal corresponding to the designated reference transmission power, the temperature represented by the measurement signal, and the voltage of the reference power supply 20 is read from the memory 45, and the time t12 in the n-th reception and idle period Rn, In.
To a DC / DC conversion circuit 49 via a digital / analog conversion circuit 48. As a result, the DC / DC conversion circuit 49 supplies the amplifier 19 with a reference bias voltage corresponding to the designated reference transmission power and corresponding to the temperature and the voltage of the reference power supply 20. After the supply of the reference bias voltage, the processing operation ends, and the process returns from step b5 to step b2.
Thereafter, until the output power change request is again given from the base station or until the communication operation is completed, steps b2 and b
The operations of 3 and b5 are periodically repeated.

As described above, by the operations of steps b2, b4, and b5, the bias voltage of the amplifier 19 is changed to the reference bias voltage corresponding to the designated reference transmission power. As described above, the reference bias voltage is set such that the current consumption of the amplifier 19 is minimized and the line quality of the electromagnetic wave is optimized when the electromagnetic wave of the reference transmission power is transmitted. Therefore, in the example of FIG. 2, after time t12, the communication device 11 transmits an electromagnetic wave of the designated reference transmission power having the optimum line quality, and the current consumption of the amplifier 19 is minimized. Of the communication devices 11, the circuit component that consumes the most current is the amplifier 19. Therefore, by reducing the current consumption of the amplifier 19, the current consumption of the entire communication device 11 can be reduced. Therefore, when operating the communication device 11 using the same battery as the related art, the communication device 11 determines the time from when the battery is installed to when the power of the battery is consumed to the extent necessary to replace the conventional communication device. It can be longer than the machine. Therefore, the number of times of battery replacement can be reduced.

In the control operation of the bias voltage performed by the conventional communication device, the bias voltage is changed in response to the rapid increase and decrease of the power supply voltage from the power supply circuit 21. Was distorted, and the line quality of electromagnetic waves had deteriorated. In the communication device 11 of the present embodiment, since the bias voltage is changed when the transmission operation is not performed, the above-described problem can be solved.

The reference bias voltage is determined according to the temperature. Therefore, even when the characteristics of the amplifier 19 change in response to the air temperature, it is possible to minimize the current consumption of the amplifier 19 and transmit an electromagnetic wave having the optimum line quality. Furthermore, the reference bias voltage is determined corresponding to the voltage of the reference power supply 20. Reference power supply 20
, The power supply voltage supplied from the power supply circuit 21 to the amplifier 19 may also change. Amplifier 1
Since the power efficiency of the amplifier 9 is determined by the bias voltage and the power supply voltage, by setting the reference bias voltage at this time as described above, the current consumption of the amplifier 19 is always maintained even when the power supply voltage may change. It is possible to transmit electromagnetic waves with the minimum amount and the optimum line quality. The parameter that determines the reference bias voltage is a physical quantity that may change the characteristics and power efficiency of the amplifier 19 in addition to the temperature and the voltage of the reference power supply 20.
Other physical quantities may be used.

The power amplifier 19 is supplied with a reference bias voltage corresponding to the maximum reference transmission power within the attenuation adjustment period W1, and after the attenuation is determined, the reference bias voltage corresponding to the designated reference transmission power. Voltage is applied. This is for the following reason.

For example, from the state where the designated reference transmission power is the minimum reference transmission power among all the reference transmission powers, the designated reference transmission power is changed to the maximum reference transmission power among the all reference transmission powers by the transmission power change request. Assume that it has changed. In this case, when the transmission power change request is received,
The amplifier 19 is supplied with a reference bias voltage corresponding to the minimum reference transmission power. At this time, if only the attenuation of the variable attenuator 18 is changed while maintaining the reference bias voltage,
The signal level of the target signal provided from variable attenuator 18 to amplifier 19 is higher than the signal level of the target signal provided from variable attenuator 18 to amplifier 19 before receiving the output power change request. At this time, the range of the signal level at the time of input of the target signal whose power can be linearly amplified by the amplifier 19 is set corresponding to the latter signal level, and the former signal level is within this range. Since the signal is often not included, the amplifier 19 saturates when the target signal of the former signal level is given. Therefore, the operation of the amplifier 19 is such that the signal level of the target signal at the time of input is not proportional to the signal level of the target signal at the time of output.
The operation becomes nonlinear. As a result, the spectrum of the electromagnetic wave may be distorted, and the line quality of the electromagnetic wave may be degraded.

Since the communication device 11 of this embodiment uses a linear digital modulation system, the operation class of the amplifier is often class A or class AB. For this reason, when setting the amount of attenuation, the communication device 11 previously sets the reference bias voltage to a reference bias voltage corresponding to the maximum reference transmission power so that the designated reference transmission power is equal to or less than the maximum reference transmission power. Since the reference transmission power is used, the nonlinear operation of the amplifier 19 can always be prevented. Therefore, when setting the amount of attenuation, it is possible to prevent the line quality of the electromagnetic wave from deteriorating. Therefore, the amount of attenuation can be reliably set based on the detected data signal.

As described above, in the communication device 11, the amount of attenuation of the variable attenuator 18 and the bias voltage of the amplifier 19 are set by the arithmetic processing of the central processing circuit 26. This makes it possible to easily shift the timing for acquiring the parameters for determining the attenuation and the bias voltage from the timing for setting the attenuation and the bias voltage. Therefore, unlike the level control circuit of the communication device of the related art, it is not necessary to make the behavior of the circuit for controlling the transmission power follow the time change of the signal level of the target signal. Therefore, it is not necessary to strictly set the characteristics of the detection circuit 31 and the central processing circuit 26, so that circuit design and manufacturing can be facilitated.

Further, since the communication device 11 does not perform analog negative feedback control unlike the level control circuit of the conventional communication device, the comparator can be omitted from the circuit for controlling the transmission power. Therefore, in addition to the circuit 17, only the variable attenuator 18, the amplifier 19, the power supply circuit 21, the directional coupler 22, and the DC / DC conversion circuit 49 are provided on the high frequency substrate 61 on which the high frequency processing circuit 17 is mounted. Once mounted, other circuit components can be mounted on the baseband substrate 62 on which the baseband processing circuit 15 is mounted. The area of the high-frequency substrate 61 is smaller than the area of the substrate on which the high-frequency processing circuit 17 is mounted in the conventional communication device. Thereby, the communication device 11 can be made smaller and lighter than the conventional communication device. Further, the baseband substrate 6
2, the central processing circuit 26, the reference power supply 20, the analog / digital conversion circuits 32 and 34,
35, temperature sensor 33, memory 45, and digital /
The analog conversion circuits 47 and 48 can be integrated into a single integrated circuit (LSI) 63. Therefore,
Further, the number of components of the communication device 11 can be reduced, and the size and weight of the communication device 11 can be reduced.

The above-mentioned communication device 11 is not limited to a portable telephone, but may be used for a radio communication device and a signal transmitter.
The detailed configuration and behavior of each circuit component of the communication device 11 are merely examples, and circuit components having other configurations and behaviors may be used. For example, a variable gain amplifier having a variable gain may be used instead of the variable attenuator. Furthermore, the circuit components for controlling the transmission power in the above-described communication device 11 may be used for purposes other than the control of the transmission power of the electromagnetic wave, for example, for controlling the signal level of an electric signal transmitted and received by the communication device of the wired communication. Good.

[0057]

As described above, according to the present invention, the level control circuit determines the rate of change by comparing the signal level of the target signal with a predetermined reference signal level by arithmetic processing. Therefore, the comparator can be omitted from the level control circuit of the prior art. Further, the level control circuit does not have to follow the time change of the signal level of the target signal. Therefore, the level control circuit can be easily designed and manufactured.

According to the present invention, the level control circuit comprises:
An amplifier is provided in addition to the level control circuit of the first aspect, a reference bias voltage capable of minimizing the current consumption of the amplifier is stored in advance, and the reference bias voltage is supplied to the amplifier. Therefore, it is not necessary to operate the level control circuit in response to the time change of the rate of change of the level changing means. Therefore, the level control circuit can be easily designed and manufactured.

Furthermore, according to the present invention, the communication device is a communication device of the time division multiplex system, and the signal level of the target signal to be transmitted by the transmitting means is determined by the period during which the target signal from another communication device is received. Adjustment is performed during a period during which transmission and reception are not performed, and signal level adjustment is not performed during a transmission period. As a result, it is possible to prevent spectrum distortion and spurious generation due to a change in signal level in the electromagnetic wave.

Further, according to the present invention, the communication device uses the reference signal level and the reference bias voltage of the target signal predetermined in correspondence with the reference transmission power of the electromagnetic wave.
The signal level of the target signal is controlled in the same manner as 2. This eliminates the need to perform transmission power control by following a change in the signal level of the target signal every time the reference transmission power specified by the specifying unit is changed. Therefore, it is possible to easily design and manufacture a part of the communication device that performs transmission power control. In addition, by integrating said parts,
The number of parts of the communication device can be reduced, and the communication device can be reduced in size and weight. Furthermore, the power consumption of the communication device can be reduced while the current consumption of the amplification means is always minimized and the line quality of the electromagnetic wave is maintained.

Further, according to the present invention, the reference bias voltage is supplied in response to a physical quantity capable of changing the characteristics of the amplifying means. According to the invention, the physical quantity is temperature. According to the invention, the physical quantity is the voltage of the power supply. Thus, even when the physical quantity including the temperature and the reference voltage changes and the characteristics of the amplifying unit change, the current consumption of the amplifying unit can always be minimized by the easy processing operation.

According to the present invention, the communication device applies the reference bias voltage corresponding to the maximum reference transmission power while the rate of change of the level changing means is increased or decreased.
Thereby, for example, when the reference signal level newly designated by the designation means is higher than the reference signal level designated by the level control circuit before this designation, the amplification means is saturated and the spectrum of the target signal is distorted, In addition, it is possible to prevent the line quality of the electromagnetic wave from deteriorating.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an electrical configuration of a communication device 11 according to an embodiment of the present invention.

FIG. 2 is a timing chart showing each operation timing of a power control operation of the communication device 11;

FIG. 3 is a flowchart illustrating an initialization operation of the power control operation.

FIG. 4 is a flowchart for explaining a transmission power control operation of the power control operation.

FIG. 5 is a block diagram illustrating an electrical configuration of a communication device 1 according to the related art.

[Explanation of symbols]

 Reference Signs List 11 communication device 15 baseband processing circuit 17 high-frequency processing circuit 18 variable attenuator 19 amplifier 20 reference power supply 21 power supply circuit 26 central processing circuit 31 detection circuit 33 temperature sensor 41 designation unit 42 attenuation amount control unit 43 bias voltage control unit 45 memory 49 DC / DC conversion circuit

Claims (8)

[Claims] 1. A level control circuit for increasing or decreasing a signal level of a predetermined target signal to a predetermined reference signal level by a level changing means having a variable rate of change of the signal level, wherein the signal output from the level changing means is The signal level of the signal is compared with the reference signal level by arithmetic processing. When the signal level does not match the reference signal level, the rate of change of the level changing means is increased or decreased by a predetermined ratio, A level control circuit, further comprising a change rate control means for maintaining the change rate when the levels match. 2. A signal level of a predetermined target signal is increased or decreased to a predetermined reference signal level by adjusting means including a level changing means having a variable rate of change of the signal level and an amplifying means having a variable bias voltage. In the level control circuit, a memory for storing the reference signal level and a predetermined reference bias voltage for minimizing the current consumption of the amplification means when outputting the target signal of the reference signal level from the adjustment means. Means for comparing the signal level of the target signal output from the adjustment means with the reference signal level stored in the storage means by arithmetic processing, and when the signal level does not match the reference signal level, Change rate control means for increasing or decreasing the change rate by a predetermined rate, and maintaining the change rate when the two signal levels match; , Level control circuit comprising a bias voltage supply means for providing a reference bias voltage stored in the storage means to the amplifying means. 3. A signal level of a predetermined target signal is adjusted to a predetermined reference signal level by adjusting means,
In the time-division multiplexing communication device transmitting by the transmitting unit, the adjusting unit adjusts the signal level of the target signal when the transmitting unit does not transmit the target signal, and adjusts the signal level of the target signal when transmitting the target signal. A communication device characterized in that the level is not adjusted. 4. A signal level of a predetermined target signal is adjusted in a plurality of predetermined reference transmission powers by adjusting means including a level changing means having a variable rate of change of the signal level and an amplifying means having a variable bias voltage. In a communication device that increases or decreases the signal level for transmitting the electromagnetic wave of the reference transmission power specified by the specifying means and transmits the electromagnetic wave, the reference transmission power and the reference transmission power A predetermined reference signal level for transmitting the electromagnetic wave, and a predetermined reference bias voltage for minimizing the current consumption of the amplifying means when transmitting the electromagnetic wave and for setting the line quality of the electromagnetic wave to the predetermined quality. A storage means for storing in association with, a signal level of the target signal output from the adjustment means, and a signal level of all reference signal levels stored in the storage means. The reference signal level corresponding to the reference transmission power specified by the specifying means is compared by arithmetic processing, and when the signal level does not match the reference signal level, the rate of change of the level changing means is determined in advance. The change rate control means for maintaining the change rate when the two signals coincide with each other, and the reference transmission power specified by the specifying means among all the reference bias voltages stored in the storage means. And a bias voltage supply means for supplying a reference bias voltage to the amplification means. 5. A physical quantity detecting means for detecting a physical quantity which changes a characteristic of the bias voltage supplying means, wherein a plurality of the reference bias voltages are prepared corresponding to the physical quantity, and wherein the bias voltage supplying means comprises Providing, to the amplifying means, a reference bias voltage corresponding to the reference transmission power specified by the specifying means and corresponding to the physical quantity detected by the physical quantity detecting means among all the reference bias voltages stored in the means. 5. The method according to claim 4, wherein
Communication device as described. 6. The communication device according to claim 5, wherein the physical quantity is a temperature. 7. The communication device according to claim 5, further comprising a reference power supply for supplying a predetermined voltage to the amplification unit, wherein the physical quantity is a voltage of the reference power supply. 8. The bias voltage supply means, when the change rate is increased or decreased by the change rate control means, to a maximum reference transmission power among all the reference bias voltages stored in the storage means. A corresponding reference bias voltage is supplied to the amplifying unit, and when the rate of change is maintained, a reference transmission corresponding to the reference signal level specified by the specifying unit out of all the reference bias voltages stored in the storage unit. 5. The communication device according to claim 4, wherein power is supplied to said amplification means.