JPH01129602A - Controller for antenna element - Google Patents

Abstract

PURPOSE:To eliminate the trouble of setting the length of an antenna element by controlling the length of an antenna element by a drive section based on an output signal from a tuning section of a radio equipment. CONSTITUTION:A voltage division VD of a potentiometer 31 due to the change in the contraction/expansion of a moving element 5a of an antenna 5 and a voltage VT of a desired reception frequency set to a receiver 6' is given to comparator circuits 41, 42. The circuits 41, 42 send voltages V3, V4 respectively to relay drive circuits 23, 24 depending on the difference between the voltages VT and VE and the relay circuit 21 drives a motor 11 and the relay circuit 22 changes the drive direction of the motor 11. The motor 11 is driven by a supply voltage from a power supply 9 and an output VD of the meter 31 is changed depending on the elongation/contraction of the element 5a. The output V3 of the circuit 41 is stopped at a point of time when the relation of VT=VB exists to deenergize the relay circuit 21 and to stop the motor 11. Thus, the elongation/contraction of the element 5a is stopped and the antenna element length corresponding to the desired frequency is set.

Description

[Detailed Description of the Invention] [Summary] When setting the length of an antenna element according to a desired frequency, the length of the antenna element is controlled by a drive unit based on an output signal from a tuning unit of a radio device. This eliminates the trouble of setting the length of the antenna element.

[Industrial application field]

The present invention relates to an antenna element control device for controlling the antenna element length of a radio device.

Generally, when a desired frequency is to be received in a radio device that uses a wide range of frequencies, an antenna element having a length suitable for the desired frequency is selected. This means that
When receiving radio waves at a desired frequency that are weak against particularly strong jamming waves, use an antenna with a length that is more suitable for the desired frequency than when using a single-length antenna element with high gain near a specific frequency. Using elements has the advantage of easier reception.

[Conventional technology]

Conventional radio equipment uses an antenna with a telescoping antenna whose length can be freely changed to suit a desired frequency.

The length of the element of this antenna having a retractable element can be changed manually or electrically (for example, driven by a motor).

[Problem that the invention seeks to solve]

If you want to manually change the length of the above-mentioned telescopic antenna, if the antenna is attached externally, such as in a car, you will have to get out of the car and adjust the antenna elements each time the frequency is changed. As a result, the problem arises that handling is extremely troublesome. In addition, when changing the length of this antenna element electrically, the antenna is only retracted and extended by manually operating a button switch. Therefore, even if an attempt is made to adjust the length of the antenna element, a problem arises in that it is difficult to match the length to a length corresponding to a desired frequency when the length setting of the element is finely adjusted. It is also possible to prepare antenna elements of several different lengths depending on the frequency used.
This poses a problem in that it takes time to select an antenna element, change antenna element connections, etc. each time the frequency is changed, making the handling extremely troublesome.

The present invention was developed in view of the above-mentioned problems, and an object of the present invention is to provide an antenna element control device that controls the length of an antenna element so that the length of the antenna element can be adjusted to a length suitable for a desired frequency. That is.

[Means for solving problems]

FIG. 1 is a block diagram showing the basic configuration of an antenna element control device according to the present invention. In this figure, ■ is a driving part, which expands and contracts the movable element 5a with respect to the fixed element 5b in the movable element 5a and the fixed element 5b forming the antenna element 5, thereby changing the length of the antenna element 5. Reference numeral 2 denotes a drive control section, which performs control for switching the drive direction of the drive section 1.

Reference numeral 3 denotes an element length detection section, which detects the length of the antenna element 5 changed by the drive section 1. Reference numeral 4 denotes a drive switching section, which switches the drive direction of the drive section 1 via the drive control section 2 based on the output signal from the tuning section 6a forming the wireless [6] and the detection signal from the element length detection section 3.

[For production]

With the above configuration, when the receiving frequency is changed in the radio device 6, an output signal corresponding to the changed receiving frequency is sent to the drive switching section 4 from the tuning section 6a. Further, a detection signal obtained by detecting the length of the antenna element 5 by the element length detection section 3 is also input to the drive switching section 4 . As a result, the drive switching unit 4 determines the expansion/contraction direction of the movable element 5a of the antenna element 5 according to the comparison between the output signal and the detection signal, and the drive control unit 2 determines the expansion/contraction direction of the movable element 5a of the antenna element 5 according to the determined expansion/contraction direction. The drive direction of the drive unit 1 is switched and driven. Thereby, the drive unit 1 expands and contracts the movable element 5a in the determined direction. Further, the length of the antenna element 5 expanded or contracted at this time is detected by the element length detection section 3, and a detection signal is sent to the drive switching section 4. The drive switching section 4 stops driving the drive section 1 via the drive control section 2 in response to a comparison between this detection signal and the output signal from the tuning section 6a. As a result, the length of the antenna element is set to a length corresponding to the changed receiving frequency.

〔Example〕

FIG. 2 shows one embodiment of the present invention, in which it is applied to a receiver 6'. In this figure, the drive unit 1 is composed of a motor 11, and expands and contracts the movable element 5a relative to the fixed elmmate 5b in the antenna element 5.

The drive control section 2 includes relay circuits 21 and 22 and relay drive circuits 23 and 24, and drives the motor 11 in a predetermined direction, that is, expands and contracts the movable element 5a.

The element length detection section 3 includes, for example, a potentiometer 31 that is linked to a motor 11, and a voltage that is divided in proportion to the movable element 5a that is expanded and contracted by the motor 11 (that is, a terminal P of the potentiometer 31).

and P2) changes. The drive switching section 4 is the first
Due to the voltage difference Δ■ between the output voltage ■↑ from the electronic tuning circuit 60, which is composed of the voltage comparison circuit 41 and the second voltage comparison circuit 42 and serves as the tuning section 6a of the radio device 6, and the output voltage vn from the potentiometer 31, The drive direction of the motor 11 is determined, and the relay drive circuit 23, the relay circuit 21, or the relay drive circuit 24. Motor 1 via relay circuit 22
1 in the determined direction. This first voltage comparison circuit 41 determines whether the motor 11 is to be in a driving state or a non-driving state. On the other hand, the second voltage comparison circuit 4
In step 2, the driving direction of the motor 11 (for example, right turn or left turn) is determined. 9 is a power source.

In the above configuration, by setting the receiver to a desired reception frequency, the output voltage VT corresponding to this reception frequency is sent from the tuning circuit 60 to the first voltage comparison circuit 41 and the second voltage comparison circuit 42, respectively. . Also, the first
The voltage comparison circuit 41 and the second voltage comparison circuit 42 also receive an output voltage V generated by the partial pressure of the potentiometer 31, which changes in proportion to the expansion and contraction of the movable element 5a of the antenna element 5. As a result, the first voltage comparator circuit 41 sends the output voltage 3 to the relay drive circuit 23 when the voltage difference between the output voltage vT and the output voltage VD (ΔV=V ar) exceeds a predetermined value. do. In the relay drive circuit 23, the relay circuit 21 is turned on and the motor 11 is driven by this output voltage V3. On the other hand, in the second voltage comparison circuit 42, the output voltage ■7 and the detection voltage ■. When the voltage difference between V and V exceeds a predetermined value, the output voltage V4 is sent to the relay drive circuit 24. In the relay drive circuit 24, the current direction of the relay circuit is switched by this output voltage V4 to change the drive direction of the motor. As a result, the supply voltage from the power source 9 is applied to the motor 11 via the relay circuits 21 and 22, so that the motor 11 is driven, and the movable element 5a begins to expand or contract with respect to the fixed element 5b. The output voltage VD generated by the partial voltage of the potentiometer 31 also changes in proportion to the expansion or contraction of the movable element 5a, that is, the voltage between terminals P1 and P2 of the potentiometer 13, that is, the output voltage VD changes. Further, when the output voltage 1 becomes equal to the output voltage V, the output voltage V from the first voltage comparison circuit 41 is not sent to the relay drive circuit 23. Therefore, the relay circuit 21 is turned off and the motor 11 stops driving, so that the movable element 5a stops expanding or contracting, thereby setting the length of the antenna element corresponding to the desired frequency.

FIG. 3 is a circuit diagram showing a specific example of the embodiment of FIG. 2.

In FIG. 3, the relay circuit 21 is a relay coil 21a.
and a relay contact 21b, and the relay circuit 22 includes relay contacts 22a, 22b and a relay coil 22c.
Consisting of These relay contacts 22a, 22b are normally closed contacts aLbl and normally open contacts a2. b2 respectively. The relay drive circuit 23 includes a transistor 23a and a resistor 23.
The relay drive circuit 24 consists of a transistor 24a, a resistor 24a, and a Zener diode 23d.
b and a Zener diode 24C. The first voltage comparison circuit 41 is a differential amplifier circuit, and this differential amplifier circuit includes transistors 41a, 41b, 41j, and a resistor 4.
1C241d, 41e, 41f, 41g, 41, 41
It and diode 41h.

Consists of 41i. On the other hand, the second voltage comparison circuit 42 includes a comparator 42a. The electronic tuning circuit 60 includes a variable capacitance diode control voltage generation circuit 61. Resistance 62. Variable capacitance diode 63. It consists of a capacitor 64 and a coil 65.

With these configurations, the circuit operation in Figure 3 can be changed to Figures 4 to 6.
This will be explained below using figures. First, when the receiving frequency is changed from a high frequency to a low frequency, that is, the relationship between the output voltage (1) from the variable capacitance diode control voltage generation circuit 61 and the output voltage VD from the potentiometer 31 becomes V at this time. >V, in FIG. 3, when the receiver 6' is changed from a high frequency to a low frequency, the output voltage is changed from the variable capacitance diode control voltage generation circuit 61 to the variable capacitance diode 63 via the resistor 62. ■
This output voltage (7) is applied to the transistor 41a via the resistor 41c of the first voltage comparator circuit 41.
It is also applied to the inverting input terminal (-) of the comparator 42a of the second voltage comparison circuit 42. On the other hand, the output voltage V generated by the voltage division of the potentiometer 31 is inputted to the transistor 41b and the non-inverting input terminal (+) of the comparator 42a via the resistor 41d of the first voltage comparison circuit 41. As a result, the output voltage V at the connection points t and d within the first voltage comparison circuit 41. Ua is the output voltage Va and the output voltage ■. The correlation shown in FIG. 5 is shown for the voltage difference ΔV between These output voltages V (the output voltage V at the confluence S of the JUT diodes 41h and 41i) have a correlation as shown in FIG. As a result, when the output voltage (2) exceeds the predetermined value (4), a Zener voltage is generated in the Zener diode 23d and the transistor 23a is turned on.

Therefore, current flows through the relay coil 21a, turning on the relay contact 21b, and the motor 11 becomes driven.

On the other hand, the output voltage V of the comparator 42a. Ul shows a correlation as shown in FIG. 4 with respect to the voltage difference V between the output voltage 7 and the output voltage 2. This comparator 42a
■ Output voltage. When UT exceeds a predetermined value (3), a Zener voltage is generated in the Zener diode 24d, turning on the transistor 24a. For this reason, the relay coil 22c
When current flows through the relay contacts 22a and 22b, the contacts of the relay contacts 22a and 22b are switched from the normally closed contacts aLbl to the normally open contacts a2 and b2, respectively, that is, the polarity of the motor 11 is switched. Therefore, the polarity of the motor 11 is switched and the movable element 5a begins to extend. As the movable element 5a expands, the terminal P of the potentiometer 31
The output voltage 1 between 1 and P2 also increases, and the voltage difference ΔV between the output voltage 7 from the variable capacitance diode control voltage generation circuit 61 and this output voltage VD begins to decrease. As a result, when this voltage difference ΔV falls within the range of ■1 to v2 (indicates the range including circuit variations), the output voltage v3 at the confluence S in the first voltage comparator circuit 4I becomes equal to or less than the predetermined value v4. Therefore, since no Zener voltage is generated from the Zener diode 23d, the transistor 23a is turned off. As a result, no current flows through the relay coil 21a, so the relay contact 21b is turned off, the drive of the motor 11 is stopped, and the extension of the movable element 1-5a is stopped. Similarly, relay contacts 22a, 22b are normally open contacts a2. b
2, it returns to the normally closed contact aL bl. As a result, the antenna element is set to a length corresponding to the changed frequency.

Next, when the reception frequency is changed from a low frequency to a high frequency, that is, the relationship between the output voltage V7 from the variable capacitance diode control voltage generation circuit 61 and the output voltage Vll+ from the potentiometer 31 becomes V7<VD. To explain the case, in this case, the output voltage 7 from the variable capacitance diode control voltage generation circuit 61 is smaller than the output voltage VD from the potentiometer 31, so the output voltage Vs from the comparator 42a is lower than the output voltage from the relay drive circuit 2.
4, the relay drive circuit 24 is turned off and the relay contacts 22a, 22b become normally closed contacts a1.4. bl
& both remain on, i.e. motor 11
The polarity remains unchanged without being switched. On the other hand, the output voltage at the junction S in the first voltage comparison circuit 41 is
.

exceeds a predetermined value v4, the relay drive circuit 23 is turned on as described above, and the relay contact of the relay circuit 21 is
21b is turned on. As a result, the motor 11 is driven without switching its polarity, and the movable element 5a begins to contract. As the movable element 5a contracts, the output voltage VD between terminals P1 and P2 of the potentiometer 31 also decreases, and the voltage difference V between the output voltage VT from the variable capacitance diode control voltage generation circuit 61 and this output voltage VD decreases. Begin to. As a result, this voltage
is within the range of V, ~V2, the first voltage comparator circuit 41
When the output voltage V, at the confluence point S in the
is also turned off. As a result, the driving of the motor 11 is stopped and the shortening operation of the movable element 5a is stopped, so that the antenna element 5 is set to have a length corresponding to the changed frequency. Note that in the electronic tuning circuit 60, the output voltage V7 from the variable capacitance diode control voltage generation circuit 61
changes the capacitance of the variable capacitance diode 63 via the resistor 62, and forms a parallel resonant circuit by connecting the capacitor 64 and the variable capacitance diode 63 connected in series in parallel with the coil 65, thereby forming the antenna element 5. The received radio waves are tuned to the desired frequency you set.

Further, FIG. 7 is a circuit diagram showing another embodiment of the present invention. In FIG. 2, the first voltage comparator circuit 41 and the second voltage comparator circuit 42 are used to determine whether the motor 11 is driven or not.
In this figure, the first voltage comparison circuit 43 and the second voltage comparison circuit 44 are used as the polarity switching means of the motor 11. That is, in the first voltage comparison circuit 43, the movable element 5a is extended. The second voltage comparison circuit 44 drives the motor 11 so as to retract the movable element 5a. In FIG. 7, the first voltage comparison circuit 43 and the second voltage comparison circuit 44 are composed of comparators 43a and 44a, and relay circuits 25.2
6 is relay contact 25a, 26a and relay coil 2
5b, 25c and 26b, 26c, respectively. Relay contacts 25a and 26a include contacts c1. c2
, di, and d2 are provided, and when no current flows through the relay coils 25b, 25c, 26b, and 26c, none of the contacts are turned on. Other components that are similar to the functional elements shown in FIG. 3 are designated with the same reference numerals or symbols. In these configurations, due to the voltage difference ΔV between the output voltage VT from the variable capacitance diode control voltage generation circuit 61 and the output voltage VD from the potentiometer 31, the output voltage from the comparator 43a or 44a changes to the relay drive circuit 2.
3 or 24. That is, as shown in FIGS. 8 and 4 (comparator 44a has almost the same output characteristics as comparator 42a), the voltage difference ΔV and the output voltage Vout from comparator 43a or 44a
Due to the correlation between the comparator 43 and
When the output voltage from a or 44a exceeds a predetermined value V3, transistor 23a or 24a is turned on and current flows through relay coils 25b, 26b or 25c, 26c. As a result, contact c at relay contact 25a
1 or 02 is turned on, and the contact d1 or d2 of one relay contact 26a is turned on. As a result, the power supply 9. Contact cl, energizing path for motor 11 and contact d1 or power source 9. Contact point c2. An energizing path for the motor 11 and the contact d2 is formed, and the motor 11 is driven according to the direction of the energizing path. From this, the movable element 5a begins to expand or contract. As mentioned above, the output voltage Va from the potentiometer 31, which changes in proportion to the expansion or contraction of the movable element 5a, becomes equal to the output voltage Va from the variable capacitance diode control voltage generation circuit 60, and the comparator 4
When the output voltage from 3a or 44a is desired to be delivered, this movable element 5a stops extending or retracting. This sets the length of the antenna element corresponding to the desired frequency.

In addition, in the above embodiments, the relay circuit 2L is used for driving and non-driving the motor 11 and for switching the polarity of the motor 11.
22, 25, and 26, semiconductor switches may be used instead of these relay circuits 21, 22, 25, and 26. Further, although the potentiometer 31 used in the above embodiments has a resistance change characteristic that allows the length of the antenna element 5 to almost match the reception frequency, it is necessary to compensate for variations in the resistance change characteristic of the potentiometer 31. Alternatively, a potentiometer as shown in FIG. 9 may be used. That is, in FIG. 9, this potentiometer has five taps TP, for example.
It consists of a tapped variable resistor 314 with a The resistance change characteristics are compensated by each variable resistor.

In addition, in FIG. 10, the potentiometer 3 is controlled by the motor 11.
1 and a configuration for driving the movable element 5a. In this figure, a gear 51a is connected to the rotating shaft of the motor 11 via a speed reducer (not shown).

31b are connected, and a sawtooth movable plate 52a connected to the movable element 5a and a sawtooth movable plate 31a connected to the movable contact of the potentiometer 31 are connected to these gears 51a.
, 31b are partially engaged with each other. As a result, the motor 11 moves the gears 51a and 31 in the direction of arrow P.
When b rotates, the movable element l-5a begins to extend, and the movable contact of the potentiometer 31 slides to the right. Also, the gear 5 is moved in the direction of arrow Q by the motor 11.
1. When a and 31b rotate, the movable element 5a begins to contract and the movable contact of the potentiometer 31 slides to the left. In this case, the antenna element 5a
The length and the partial pressure ratio of the potentiometer 31 have, for example, a one-to-one correspondence.

Note that although the embodiments of the present invention are applied to a receiver, they may also be applied to a transmitter.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to adjust the length of the antenna element using the drive unit according to the output signal from the tuning unit of the radio, so it is possible to adjust the length of the antenna element in accordance with the output signal from the tuning unit of the radio. This eliminates the hassle of By setting the length of the antenna element corresponding to the desired frequency, the reception level of the radio waves received by the radio device, the duty ratio between radio wave emission and stop, and impedance matching between the antenna element and the radio device. This improves the reception level under adverse conditions such as interference.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the principle configuration of an antenna element control device based on the present invention, FIG. 2 is a diagram showing an embodiment of the present invention, and FIG. 3 is a circuit showing a specific example of the embodiment in FIG. 2. Figure 4 shows the voltage difference Δ■ and the output voltage V of the comparator 42a.
. FIG. 5 is a diagram showing the correlation with U7. FIG. FIG. 6 is a diagram showing the correlation between the voltage difference Δ■ and the output voltage Vs at the junction S in the first voltage comparison circuit 41, and FIG. 7 is a diagram showing the correlation with LIT. FIG. 8 shows the voltage difference Δ■ and the output voltage V of the comparator 43a. FIG. 9 is a diagram showing the correlation with LIT, FIG. 9 is a diagram showing another example of the configuration of the potentiometer 31, and FIG. 10 is a diagram showing a configuration for driving the potentiometer 31 and the movable element 5a by the motor 11. 1... Drive section, 2... Drive control section, 3...
- Element length detection section, 4... Drive switching section, 5... Antenna element, 5a... Movable element, 5b... Fixed element, 6... Radio device, 6a... Tuning section. Voltage difference ΔV and output voltage V of comparator 43a. 8th 31a 31b 31c 31ciTP showing correlation with ut
TP TP TP TPp・
^^AA To the back AA To the people Eight people Eight people
, Engineering A 1 1 1/r 1'h 7 children 7'/-J
-4”Q 1 Trigram rt-wwwwvwvvvvvvvv
wv-"Section 3"°- No. 90 showing another configuration example of the potentiometer 31 31A...Tapped variable resistors 31a, 31b, 31c, 31cl ++ Variable resistor TP-... Tap movable element 5a Structure for driving 31a... Serrated movable plate 31b Gear 51a... Serrated movable plate 51b... Gear

Claims (1)

[Claims] 1. Movable element (5a) and fixed element (5a)
b), which consists of an antenna element (5) that receives radio waves to be tuned by the tuning section (6a) of the radio device (6), and a movable element (5a) that expands and contracts with respect to the fixed element (5b). a drive unit (1) that changes the length of the antenna element (5); and a drive unit (1) that changes the length of the antenna element (5);
a) a drive control unit (2) that controls the drive direction of the drive unit (1) that extends and contracts the antenna element, comprising: an element length detection unit (3) that detects the length of the antenna element; Detection signal (V_D) from the element length detection section (3)
and a drive switching section (4) that switches the drive direction of the drive section (1) via the drive control section (2) according to a comparison between the output signal (V_T) from the tuning section (6a) and the output signal (V_T) from the tuning section (6a). An antenna element control device comprising: 2. The drive switching section (4) includes a first voltage comparison circuit (41
, 43) and a second voltage comparison circuit (42, 44). 3. The first voltage comparison circuit (41), in response to the comparison between the detection signal (V_D) from the element length detection section (3) and the output signal (V_T) from the tuning section (6a),
The antenna element control device according to claim 2, which drives or non-drives the drive section (1). 4. The second voltage comparison circuit (42), in response to the comparison between the detection signal (V_D) from the element length detection section (3) and the output signal (V_T) from the tuning section (6a),
The antenna element control device according to claim 2, wherein the driving direction of the driving section (1) is switched. 5. The first voltage comparison circuit (43) and the second voltage comparison circuit (44) receive a detection signal (V_D) from the element length detection section (3) and an output signal (V_D) from the tuning section (6a). According to the comparison with V_T), the drive unit (1)
The antenna element control device according to claim 2, wherein the antenna element control device drives the antenna element in one direction and in a direction opposite to the one direction. 6. Detection signal (V
_D) is the output voltage (V) from the potentiometer (31)
__D) The antenna element control device according to claim 1. 7. The antenna element control device according to claim 1, wherein the output signal (V_T) from the tuning section (6a) is an output voltage from an electronic tuning circuit (60). 8. The antenna element control device according to claim 1, wherein the drive section (1) comprises a motor (11). 9. The potentiometer (31) includes a plurality of tapped variable resistors (31A) and a variable resistor (31a, 31A) connected to each tap of the plurality of tapped variable resistors (31A).
The antenna element control device according to claim 6, comprising: (b), 31c, 31d).