JPS60244107A - Control circuit of high frequency electric power - Google Patents

Abstract

PURPOSE:To attain designation of the high frequency electric power in many stages with high accuracy by applying the digital designation of said electric power. CONSTITUTION:A part of a high frequency signal 101 of the output of a power amplifier 1 is detected by a coupler consisting of strip lines 7 and 8, and the wave detection voltage Vd is obtained via a diode 6. At the same time, the designated power information 151 and the designated frequency information 161 are supplied to terminals 15 and 16 respectively. The digital value decided in response said two types of information is previously stored at a prescribed address of a memory part 14. This digital value is read out according to the designated information and converted into the reference voltage through a D/A converter 13. This reference voltage is compared with the voltage Vd by an error amplifier 3, and the difference between both voltage levels is amplified and supplied to a control part 2. The power supply voltage of the part 1 is controlled by the output of the part 2. As a result, the output voltage is kept constant regardless of the frequency of a high frequency signal 100.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a circuit for controlling high frequency power such as transmission power of a mobile communication device such as a car telephone device.

(Prior art) Conventionally, transmission power control of mobile communication devices only requires constant output setting, and the number of communication channels is 20 at most.
It was about a channel. However, in recent years, when a mobile station approaches a base station, in order to prevent intermodulation and cross-modulation at the base station, either the base station sends a command or the mobile station itself performs electric field detection to reduce the mobile station's transmission power. It is starting to decline. In addition, the variable range of transmission power is from 10 dB to
It has become wider at 30 dB, and the variable range has been increased by several dB.
Increasingly, each unit is divided into 2 to 8 stages and all switching is performed. Furthermore, the number of communication channels has been significantly increased to about 300 to 1000 channels, and the frequency bandwidth used has also been reduced from the conventional 2MHz.
~3MHz to 20MHz~40MHz? ! l:
Bandwidth is becoming increasingly widespread.

Now, as a method for controlling high frequency power such as transmission power, there is a method in which all variable attenuators are inserted after the final stage of the power amplification section, and a method in which the current flowing through the power amplification section is controlled to control the total power. There are several methods, but the former is expensive, and the latter is difficult to widen the band because the characteristic of the power amplification section that the power amplification factor varies depending on the frequency is immediately reflected in the transmission output (the power deviation within the band is It had the disadvantage of being extremely large. Another high-frequency power control method is to perform detection by extracting a portion of the output power, compare and amplify the obtained detected voltage and a predetermined reference voltage in an error amplification section, and output the output from the error amplification section. Some had a circuit configuration that used signals to control the entire power amplification section so that the output power was constant. In this method, does the detected voltage have frequency characteristics? However, since the reference voltage remains constant, there is a disadvantage that a considerable amount of power deviation occurs within the band. Moreover, when the power variable range is widened, the within-band deviation of power increases, and when the power changes by 30 dB, the power deviation within the used band increases by 5 to 6 times compared to when the power is constant. In the conventional high-frequency power control circuits described above, the high-frequency power is specified by an analog circuit in either method. Therefore, the number of power specification classifications was about eight at most, and the accuracy was poor and the circuit was large.

(Object of the Invention) An object of the present invention is to provide a high-frequency power control circuit that can specify high-frequency power to a large number of stages with high precision. A power amplification section, an extraction section that extracts part or all of the high frequency power output from the power amplification section, and a portion of the high frequency power extracted by the extraction section? a detection section that detects a wave; a reference voltage generation section that generates a reference voltage having a magnitude corresponding to the designated value of the high-frequency power; and a differential voltage generation section that generates a voltage that is the difference between the output voltage of the detection section and the reference voltage. In the high frequency power control circuit, the reference voltage generation section includes a storage circuit and a conversion circuit, and a control section that controls all of the power amplification sections in a direction in which the differential voltage becomes smaller. has stored digital values representing all of the reference voltages, and the R conversion circuit converts all of the digital values into the reference voltages (Embodiments) Next, all embodiments of the present invention will be described. Detailed explanation 0 Is Figure 1 an embodiment of the present invention? FIG. In this embodiment, 1 is a power amplification section, 2 is a power supply voltage control section, 3 is an error amplification section, 4 is a capacitor, 5 is a resistor, 6 is a detection diode, 7 and 8 are strip lines, 9 is a resistor, 10
1 is an antenna, 11 is a high frequency signal input terminal, 12 is a power supply terminal, 13 is an "/A converter section, 14 is a storage section, 15 is a designated power information input terminal, and 16 is a designated frequency information input terminal.

A part of the high frequency signal 101 amplified by the power amplifying section 1 is detected by the coupler configured by the strip line 7.8, and detected by the detection diode 6 to obtain the detection voltage Vd't''.On the other hand, In order to instruct the high frequency signal 101 to have a predetermined power, specified power information is sent to the terminal 15.
Also, designated frequency information is applied to terminal 16 to indicate what the frequency of the input high frequency signal 100' is. The storage unit 14 stores designated power information 15.
1 and the designated frequency information 161, a digital value determined corresponding to both information is stored in advance. When the address is specified in the image information 151, 161, the storage unit 14 stores
All digital values at that address are read out and added to the ψA converter 13. The /A converter 13 converts the entire digital value into a reference voltage vrf.The reference voltage Vrf and the detected voltage Vd are compared in the error amplifier 3, and the difference between the two voltages is amplified.Error amplifier 3 The power supply voltage of the power amplifier section 1 is controlled by controlling the power supply voltage control section 2 using the output signal 103 of The power deviation within the band is corrected by storing the correction information for power deviation depending on the frequency in the storage unit 14. Also, the amount of information in the storage unit 14 and , ”Select all precisions of the /A converter 13.

FIG. 2 is a detailed block diagram showing a more specific example of the embodiment shown in FIG. The designated power information consists of three bits of data, each of which is applied to a terminal 38°39.40. The designated frequency information is 2-bit data, and each of these bits is applied to terminals 41 and 42. Storage unit 14
is a ROM (read-only memory). ”/A converter 1
3 is a switch array 36, a power supply 37, and resistors 19 to 3.
It consists of a 35° operational amplifier 17.

In the embodiment shown in FIG. 1 and the specific example shown in FIG. Because of the high frequency, the force can be specified with great precision into an extremely large number of stages. and,
Since the reference voltage ■rf is set taking into account not only the high frequency power but also the frequency, even if the amplification factor of the power amplifying section 1 varies depending on the frequency, the power deviation due to the frequency in the high frequency signal 101 is small. Even if the variable power range is as wide as about 30 dB, any digital value according to the designated power information 151 can be stored in the storage unit 14, so even at low power, the in-band power deviation can be reduced by the characteristic compensation 1~ of the power amplifier unit 1. Can be any value you want.

The variable power range is determined by the number of bits of the specified power information 151, the storage capacity of the storage unit 14, and the number of bits of the small r conversion unit 130, and therefore can be selected to be any value. In this embodiment, since the main part of the reference voltage generation circuit is a digital circuit, it is much smaller and more reliable than the conventional analog circuit system.

(Effects of the Invention) According to the present invention, as described above, it is possible to provide a high frequency power control circuit in which high frequency power can be specified with precision I< in a large number of stages.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a detailed block diagram showing an example in which part and all of the embodiment of FIG. 1 is further embodied. 6... Detection diode, 7, 8... Strip line, 10... Antenna, 11... High frequency signal input terminal, 12... Power supply terminal, 15... Specified power information input terminal, 16 ...Specified frequency information input terminal, 17...
- Operational amplifier, 36... Switch array, 37...
Reference power supply, 38-40...Specified power information input terminal, 4
1 to 42...Specified frequency information input terminal.

Claims (1)

[Claims] (1) A power amplification section that fully amplifies the power of a high-frequency signal, an extraction section that extracts a part or all of the high-frequency power generated by the output of this power amplification section, and a portion of the high-frequency power extracted by this extraction section that is detected. a reference voltage generation section that generates a reference voltage of a magnitude corresponding to the specified value of the high frequency power, and a difference voltage generation section that generates a voltage that is the difference between the output voltage of the detection section and the reference voltage. and a control section that controls all of the power amplification sections in a direction in which the differential voltage becomes smaller, the reference voltage generation section includes a memory circuit and a "/"/
Unlike the A conversion circuit, the storage circuit stores a digital value representing the reference voltage, and the A conversion circuit converts all of the digital values into the reference voltage.
Features a high-frequency power control circuit. (2. In the high-frequency power control circuit according to claim 1, the storage circuit stores at least two different digital signals according to the frequency of the high-frequency signal for one specified value of the high-frequency electric power. The address where the digital value is stored in the storage circuit is determined by the specified value and the specified value of the frequency, and the storage circuit stores the address according to the specified value of the high frequency power and the frequency. A high-frequency power control circuit, characterized in that the digital value is read out from the RF power control circuit and sent to the A/A converter.