JPH10145247A - Transmitting output controller of radio equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a circuit, to reduce costs and part packaging man-hour and to make radio equipment small by generating a pulse signal, converting it into a direct current voltage and generating a reference voltage for transmitting the output control. SOLUTION: A CPU 61 outputs a pulse signal, a waveform-shaping filter 62 converts the pulse signal into a direct current voltage, through which a reference voltage for transmitting output control is acquired. The pulse width of the pulse signal that is outputted from the CPU 61 is changed into six types, by changing data from the CPU through an encoder which controls a transmitting output among a high output, an intermediate output and a low output about a VHF band and a UHF band. When the pulse width of the pulse signal is changed into six types in this way, six types of direct current voltages can be acquired by converting each pulse signal into a direct current with the filter 62, and when these six types of reference voltages are selectively supplied to a comparative amplifier circuit 53, transmitting outputs of the VHF and UHF bands can be controlled separately in the high, intermediate and low outputs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission output control device for a radio, which switches the transmission output of the radio to, for example, a high output, a medium output, a low output, and the like.

[0002]

2. Description of the Related Art When making a call using a radio, the transmission output of the radio is switched to an appropriate output in accordance with the communication distance and the like, which is preferable from the viewpoint of proper use of radio waves. . FIG. 6 is a circuit diagram showing a conventional transmission output control device for achieving the above-mentioned object. This circuit is a case where the conventional device is applied to a two-band radio in a VHF band and a UHF band. In FIG. 6, a VHF band high frequency signal is power-amplified by a VHF band final amplifier 11 and then supplied to an antenna 13 via a low pass filter 12. The UHF band high-frequency signal is amplified by a UHF band final amplifier 14 and then passed through a low-pass filter 15.
, And supplied to the antenna 13 via the high-pass filter 16. In the VHF band, the transmission output is detected by the output detector 17 from the low-pass filter 12, and the detected voltage from the output detector 17 is compared with the reference voltage by the comparison amplifier circuit 18, and the difference voltage is obtained. Is sent to the transmission output control circuit 19, and the transmission output control circuit 19
By controlling the drive voltage of the HF band final amplifier 11, the transmission output in the VHF band can be controlled to a predetermined output corresponding to the reference voltage.

Here, the reference voltage generation circuit in the VHF band is:
Three variable resistors VR1, VR2, VR3 connected in series via a resistor 20a between a power supply Vcc and ground, and a switch SW1 for short-circuiting one or two of the three variable resistors VR1, VR2, VR3. , SW2, CP
Turning on and off the switches SW1 and SW2 with the output of the shift register 22 to which data is input from U21;
By adjusting the variable resistors VR1, VR2, VR3, 3
Different types of reference voltages can be generated. By selectively supplying these three types of reference voltages to the comparison amplifier circuit 18, the transmission output in the VHF band can be controlled to a high output, a medium output, and a low output by the control method described above.

[0004] The transmission output in the UHF band is also controlled by VHF.
It is exactly the same as the band side. That is, on the UHF band side, the transmission output is detected by the output detector 23 in the low-pass filter 15, and the detection voltage from the output detector 23 is compared with the reference voltage by the comparison amplifier circuit 24, and the difference is calculated. The voltage is transmitted to the transmission output control circuit 19, and the transmission output control circuit 19 controls the drive voltage of the UHF band final amplifier 14, thereby controlling the transmission output in the UHF band to a predetermined output corresponding to the reference voltage. The UHF band reference voltage generation circuit uses the power supply Vcc as in the VHF band side.
And three variable resistors VR4, VR5, VR6 connected in series between the ground and the ground via a resistor 20b, and two switches SW3, SW4 for short-circuiting.
3, SW4 ON / OFF control and variable resistors VR4, VR
5, three kinds of reference voltages are generated by adjusting VR6. By selectively supplying these three types of reference voltages to the comparison amplifier circuit 24, the transmission output in the UHF band can be switched to a high output, a medium output, and a low output.

[0005]

However, in the conventional transmission output control device as described above, a total of six variable resistors VR1 (three in each band) are used to generate a reference voltage.
To VR6, there is a problem that parts cost and man-hours for mounting parts increase, and the area of the printed circuit board on which the parts are mounted becomes large, which hinders downsizing of the wireless device. Also, since the six variable resistors VR1 to VR6 must be adjusted, the number of adjustment steps increases, and the transmission output is adjusted to close the case after turning and adjusting the variable resistors VR1 to VR6 on the printed circuit board. There is also a problem that the value slightly fluctuates. Further, in the above-described apparatus, the comparison amplifier circuits 18 and 24 are also provided exclusively for each band, like the output detectors 17 and 23. Therefore, the parts cost and the parts mounting man-hour are further increased, and the area of the printed circuit board is reduced. There is also a problem that it grows.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a pulse generating circuit for generating a pulse signal, and converting a pulse signal generated from the pulse generating circuit into a DC voltage to a reference voltage. And a means for detecting a transmission output to generate a detection voltage,
A comparison amplifier circuit for comparing the detection voltage from the means with the reference voltage; and a means for controlling a transmission output to a transmission output value corresponding to the reference voltage based on a comparison result of the comparison amplifier circuit. And a transmission output control device for a wireless device. Further, as another feature of the present invention, only one comparison amplifier circuit is used in a plurality of frequency bands and only one comparison amplifier circuit is provided.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a transmission output control apparatus for a radio device according to the present invention. FIG. 1 and FIG. 2 are circuit diagrams showing an embodiment of the present invention, in which the present invention is applied to a two-band radio in a VHF band and a UHF band. FIG. 1 shows a transmission unit 31 and a control unit 32.
FIG. 2 shows the display unit 33. In the transmission unit 31 of FIG. 1, a VHF band high-frequency signal is supplied to a VHF band final amplifier (power amplifier) 42 via a first changeover switch 41 for switching between the VHF band and the UHF band. After being amplified, it is supplied to an antenna 45 via a second switch 43 for switching between the VHF band and the UHF band and a low-pass filter 44.
The UHF band high frequency signal is supplied to a UHF band final amplifier (power amplifier) 47 via a first switch 46 for switching between the UHF band and the VHF band. Obi and V
The signal is supplied to the antenna 45 via a second switch 48 for switching the HF band, a low-pass filter 49 and a high-pass filter 50.

In the VHF band, a low-pass filter 4
The transmission output is detected by the output detector 51 in four parts,
Similarly, in the UHF band, the transmission output is detected by the output detector 52 in the low-pass filter 49 portion. And
As a result of this transmission output detection, the detection voltage output from the output detector 51 or the output detector 52 is compared with a reference voltage, which will be described later, by a comparison amplifier circuit 53. According to the comparison result, a transmission output control circuit 54 By controlling the drive voltage of the VHF band final amplifier 42 or the drive voltage of the UHF band final amplifier 47, the transmission output in the VHF band or the transmission output in the UHF band can be controlled to a predetermined output corresponding to the reference voltage. ing. It should be noted that only one comparison amplifier circuit 53 is provided and is selectively used in common in the VHF band and the UHF band.

In the control section 32, reference numeral 61 denotes a CPU (Central Processing Unit), which operates as a pulse generating circuit as one function and outputs a pulse signal.
Moreover, this CPU 61 is the CPU of the display unit 33 in FIG.
Serial communication is performed with the CPU 71, and a plurality of pulse signals having different pulse widths are output based on data from the CPU 71 (this data changes according to a signal from the encoder 72 of the display unit 33). A waveform shaping filter 62 is connected to the output of the CPU 61 as a waveform conversion circuit for converting a pulse signal into a DC voltage. This waveform shaping filter 6
Specifically, as shown in FIG. 3, the circuit 2 includes a two-stage integrating circuit (not limited to two stages) including resistors R1 and R2 and capacitors C1 and C2. The output of the waveform shaping filter 62 is connected to the reference voltage input terminal of the comparison amplifier 53.

That is, in this embodiment, the CPU 6
1 outputs a pulse signal. The pulse signal is converted into a DC voltage by the waveform shaping filter 62 to obtain a reference voltage for transmission output control. And VH
In order to control the transmission output to high output, medium output, and low output in the F band and the UHF band, the encoder 72 is turned to change the data from the CPU 71 and change the pulse width of the pulse signal output from the CPU 61 to six types. . When the pulse width of the pulse signal is changed to six types in this manner, each pulse signal is converted into a DC voltage by the waveform shaping filter 62,
Six types of reference voltages can be obtained. By selectively supplying these six types of reference voltages to the comparison amplifier circuit 53, the transmission output can be set to a high output, a medium output, and a low output in the VHF band and the UHF band, respectively. Can be controlled.

The pulse width of the pulse signal for controlling the transmission output to high output, medium output and low output in the VHF band and the UHF band is determined by adjusting the encoder 72 while monitoring the transmission output. Once the pulse width is determined in this manner, the data of the pulse width is
Is stored in the storage circuit 63 connected to the storage device. Thereafter, by reading the stored pulse width data from the storage circuit 63, a pulse signal of a desired pulse width is output instantaneously, and the transmission output is set to a high output, a medium output in the VHF band and the UHF band, and
It can be set to low output instantaneously.

The above operation will be described in more detail.
The encoder 72 is called a rotary encoder, and is a rotary pulse switch. The encoder 72 generates two types of pulse signals from the rotation of the shaft,
A rotation operation and a rotation direction are detected from the two pulse signals. The CPU 71 to which the pulse signal is supplied from the encoder 72 counts up or down according to the pulse signal from the encoder 72, and outputs 256 kinds of 8-bit data. Then, the CPU 61 to which data is supplied from the CPU 71
A pulse signal having 256 pulse widths is output according to the data from the PU 71. That is, the CPU 61
According to the data from the CPU 71, as shown in FIG. 4A, one cycle = 15.62 mSec, and the pulse width is
As shown in (b), a pulse signal that changes in 256 ways of 61 μSec × n (where n is an integer of 1, 2, 3,... 256) is output. Then, this pulse signal is converted into a two-stage integrating circuit (resistors R1 and R2 are 2.2 kΩ,
Capacitors C1 and C2 are converted to a DC voltage by a waveform shaping filter 62 of 0.1 μF), so that about 5 m
A reference voltage that changes in 256 steps from V to 4740 mV can be obtained. By supplying the 256 reference voltages to the comparison amplifier circuit 53, the transmission output can be controlled in 256 ways. In the actual output adjustment, the desired high output, middle output, and low output are adjusted in the VHF band and the UHF band, respectively, from among the 256 patterns, and the data of six pulse widths (from the CPU 71) from which these output values are obtained are obtained. The data may be supplied, or may be data generated independently by the CPU 61) in the storage circuit 63 composed of an EEPROM. Note that the CPU as described above
As 61, μPD78058 manufactured by NEC can be used.

In addition to the CPU 71 and the encoder 72, a power switch 73, a power switch 74, a VHF band selection key 75, a UHF band selection key 7
6, a sub-band down key 77, a sub-band up key 78, an entry key 79, and a function key 80 are provided. Although not shown, a push talk switch is provided at a predetermined position such as a side surface of a microphone connected to the wireless device. The signals from these functional units are processed by the CPU 71. Further, an adjustment switch 64 for setting a predetermined input port to the ground voltage is connected to the CPU 61 of the control unit 32 of FIG. 1 which performs serial communication with the CPU 71. With reference to these configurations and the flowchart of FIG. 5, one procedure for setting the wireless device in the adjustment mode and actually adjusting the transmission output will be described last.

When adjusting the transmission output, the power switch 73 is first turned on as shown in step S1. next,
As shown in step S2, the adjustment switch 64 is turned on to set a predetermined input port of the CPU 61 to the ground voltage, and at the same time, the function key 80 and the entry key 79 are turned on. As a result, the wireless device enters the adjustment mode as shown in step S3. Next, as shown in step S4, the sub-band up key 78 is pressed to select the frequency band for output adjustment, ie, VHF or UHF band, and the output intensity, ie, high output, middle output or low output. . Specifically, when the sub-band up key 78 is pressed once, the VHF
When the sub-band up key 78 is pressed once more, the middle output is output in the VHF band, and when the sub-band up key 78 is pressed once more, the output is high in the VHF band, and the sub-band up key 7 is pressed.
Pressing 8 once more selects low output in the UHF band, pressing the sub-band up key 78 once more selects medium output in the UHF band, and pressing the sub-band up key 78 once selects high output in the UHF band. When the sub-band up key 78 is pressed once more, the output returns to low in the VHF band. Then, at the selected frequency band and the output intensity, the push talk switch is pressed as shown in step S5, and at the same time, the output is adjusted by turning the encoder 72 to obtain the desired transmission output.
When the transmission output reaches a desired value, the entry key 79 is pressed as shown in step S6, and the data of the pulse width at that time is stored in the storage circuit 63. Thereafter, it is determined in step S7 whether or not the adjustment has been completed for all frequency bands and all output intensities. If all adjustments have not been completed, the process returns to step S4 to select the next adjusted frequency band and output intensity, and step S5 To adjust the transmission output to a desired value, and repeatedly store the pulse width data in step S6. When the adjustment is completed in all frequency bands and all output intensities, the transmission output adjustment is ended. Note that the sub-band up key 78 is pressed in step S4 to
When the output intensity of the medium output and the low output is selected and the output is adjusted, if the pulse width of each output intensity expected in advance is stored in the storage circuit 63 in advance as an initial value of each output intensity, the adjustment is performed at the time of adjustment. By turning the encoder 72 to raise or lower the output intensity from its initial value, the output can be adjusted quickly. On the other hand, when the power switch 73 is turned on in step S1, the normal mode is set in step S8. In this normal mode, the VHF band or the UHF band can be selected by pressing the VHF band selection key 75 or the UHF band selection key 76, In addition, by pressing the power switch 74, the stored contents can be read out from the storage circuit 63 and the desired transmission output can be instantaneously obtained.

According to the above-described embodiment, six types of pulse signals having different pulse widths are output from the CPU 61, and the pulse signals are converted into a DC voltage by the waveform shaping filter 62 to thereby obtain six types of reference voltages. , The circuit becomes simpler than a conventional circuit that generates six types of reference voltages using six variable resistors, and it is possible to reduce parts cost and man-hours for mounting components, and to reduce the number of parts. The area of the printed circuit board to be mounted can be reduced, and the wireless device can be downsized. In addition, since the output adjustment is easy and the number of adjustment steps can be reduced, and the adjustment can be made on the display unit of the wireless device with the case of the wireless device closed, there is no problem that the transmission output slightly fluctuates from the adjusted value after the adjustment. Further, since the pulse width at which the desired transmission output is obtained is stored in the storage circuit 63, the desired transmission output can be instantaneously obtained by reading from the storage circuit 63 thereafter. The comparison amplifier circuit 53 is commonly used in the VHF band and the UHF band, and
Since only one is provided, the circuit becomes simpler, the cost of components and the number of steps for mounting components can be further reduced, and the size can be further reduced.

FIG. 1 shows a two-band radio device of a VHF band and a UHF band, and a first switch 4 for switching between high frequency signals of the VHF band and the UHF band and transmitting the signal to the antenna 45.
1 and 46 and second changeover switches 43 and 48 are provided. The first changeover switches 41 and 46 are connected to the VHF band side and the UHF band side.
The band side has the same configuration, a diode 91 having a cathode connected to the signal input terminal, a resistor 92 connected between the cathode of the diode 91 and the ground, and a diode 9.
It comprises a capacitor 93 connected between the anode 1 and the signal output terminal, and a resistor 94 having one end connected to the anode of the diode 91. The second changeover switches 43 and 48 are connected to V
The HF band side and the UHF band side have the same configuration, a diode 95 having an anode connected to a signal input terminal and a cathode connected to a signal output terminal, and a coil connected between the cathode of the diode 95 and ground. 96, a coil 97 having one end connected to the anode of the diode 95, and a resistor 98 having one end connected to the other end of the coil 97.

The other ends of the resistors 94 and 98 of the first and second changeover switches 41 and 43 on the VHF band side are connected to a changeover circuit 55.
The other ends of the resistors 94 and 98 of the first and second changeover switches 46 and 48 on the UHF band side are connected to the second output u of the changeover circuit 55. The switching circuit 55 performs serial communication with the CPU 61 of the control unit 32 and transmits data from the CPU 61 to the shift register 56.
Is supplied via With this supplied data,
The first output v or the second output u of the switching circuit 55 becomes a positive voltage. Now, when the first output v of the switching circuit 55 becomes a positive voltage, the first and second changeover switches 41 and 42 in the VHF band are used.
43, the diodes 91 and 95 are turned on, the first and second changeover switches 41 and 43 are turned on, and a high-frequency signal in the VHF band is transmitted to the antenna 45. At this time, the switching circuit 55
Is at ground voltage, and therefore U
The diodes 91 and 95 of the first and second changeover switches 46 and 48 in the HF band are turned off, and the first and second changeover switches 46 and 48 are turned off.
Since the switch 48 is turned off, the UHF band high-frequency signal is not transmitted to the antenna 45. Conversely, the second
When the output u becomes a positive voltage, the diodes 91 and 95 of the first and second changeover switches 46 and 48 in the UHF band are turned on, and the first and second changeover switches 46 and 48 are turned on.
A high frequency signal in the HF band is transmitted to the antenna 45. At this time, since the first output v of the switching circuit 55 is the ground voltage, the first and second changeover switches 41 and 43 in the VHF band are turned off, and the high frequency signal in the VHF band is not transmitted to the antenna 45. In this manner, high-frequency signals in the VHF band and the UHF band can be switched and output.

In the above embodiment, the case where the transmission output is controlled to a high output, a medium output, and a low output in the two-band radio apparatus of the VHF band and the UHF band has been described. The number of output control stages is not limited to the above embodiment. Further, the CPU 61 can output a digital signal of a plurality of digital values as a pulse signal. In that case, D / A is used as the waveform conversion circuit.
Use a converter. Also, when a digital signal is generated from the CPU 61, when a digital signal value at which a desired transmission output is obtained is determined, the digital signal value is stored in the storage circuit 63, and thereafter, the stored content is read out from the storage circuit 63. The desired transmission output can be obtained instantaneously. When a digital signal is generated as a pulse signal, a pulse generation circuit for generating the digital signal and a D / A converter can be housed in one CPU. In FIG. 1, various types of output detectors 51 and 52, such as a traveling wave reflected wave detection type, a current detection type, and a power detection type, can be used.

[0019]

As described above, according to the transmission output control apparatus for a wireless device of the present invention, a pulse signal is generated, and the pulse signal is converted into a DC voltage to generate a reference voltage for transmission output control. In addition, the circuit can be simplified, the cost and the number of parts mounting steps can be reduced, and the size of the wireless device can be reduced.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a part of an embodiment of a transmission output control device for a wireless device according to the present invention.

FIG. 2 is a circuit diagram showing a remaining part of the embodiment.

FIG. 3 is a circuit diagram showing a specific example of a waveform shaping filter used in the circuit of FIG. 1;

FIG. 4 is a waveform chart for explaining the operation of the embodiment of the present invention in detail.

FIG. 5 is a flowchart showing an actual procedure of transmission output adjustment according to the present invention.

FIG. 6 is a circuit diagram showing a conventional transmission output control device.

[Explanation of symbols]

 42, 47 Final amplifier 51, 52 Output detector 53 Comparative amplifier circuit 54 Transmission output control circuit 61 CPU 62 Waveform shaping filter 63 Storage circuit

Claims (5)

[Claims] A pulse generation circuit for generating a pulse signal; a waveform conversion circuit for converting a pulse signal generated from the pulse generation circuit into a DC voltage to generate a reference voltage; Means for generating, a comparison amplifier circuit for comparing the detection voltage from the means with the reference voltage, and a transmission output to a transmission output value corresponding to the reference voltage based on a comparison result of the comparison amplifier circuit. Control means for controlling the transmission output of the radio equipment. 2. The transmission output control device for a wireless device according to claim 1, wherein the pulse generation circuit generates a pulse signal with a plurality of pulse widths, and converts the pulse signal into a DC voltage by a waveform conversion circuit including an integration circuit. A transmission output control device for a wireless device, wherein a plurality of reference voltages are generated. 3. The transmission output control device for a radio device according to claim 1, wherein the pulse generation circuit generates a pulse signal as a plurality of digital signals, and converts the digital signals to a direct current by a waveform conversion circuit including a D / A converter. A transmission output control device for a wireless device, wherein a plurality of reference voltages are generated by converting into a voltage. 4. A transmission output control device for a radio device according to claim 2, wherein a pulse width or a digital signal value at which a predetermined transmission output is obtained is stored in a storage circuit, and the stored content is read from the storage circuit thereafter. A transmission output control device for a wireless device, wherein a pulse signal for obtaining a predetermined transmission output is instantaneously generated from the pulse generation circuit. 5. The transmission output control device for a wireless device according to claim 1, wherein only one comparison amplifier circuit is used in a plurality of frequency bands and provided. Transmission output control device.