JPH0463569B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a tuner device that can be used in transmitters and receivers of televisions, radios, stereo tuners, personal radios, and other communication devices in general.

Conventional configurations and their problems In recent years, the number of broadcast waves from televisions and radios and communication waves from communication devices has increased, and the performance of tuner devices that receive desired signals requires high tuning accuracy, stability, and reliability. Demand is increasing. on the other hand,
Reducing the manufacturing costs of these receivers, transmitters, and communication devices is also a major issue, and drastic technological development is required especially for frequency selection circuits in the high frequency section, which is difficult to rationalize.

A conventional tuner device will be described below with reference to the drawings. Figure 1 is a circuit diagram of a conventional tuner device, where 1, 2, and 3 are tuning coils, 4,
5 and 6 are trimmer capacitors, and 7, 8, and 9 are voltage variable capacitance diodes, which constitute tuners 10, 11, and 12, respectively.
The signal input to the signal input terminal 13 is sent to the amplifier 14.
is amplified and supplied to the mixer 15. On the other hand, the local oscillation signal is oscillated by the oscillator 16 and also supplied to the mixer 15, where it is mixed with the amplified signal described above to output an intermediate frequency signal to the output terminal 17, and the voltage variable capacitance diodes 7, 8, 9 was supplied with a voltage obtained by variably dividing the voltage of a DC power supply 21 by a potentiometer 22 via resistors 18, 19, and 20 for blocking AC signals.

Furthermore, FIG. 2 is a conventional component configuration diagram of the conventional tuners 10, 11, 12 in FIG.
24 is a tuning coil, 24 is a trimmer capacitor, and 25 is a voltage variable capacitance diode, which are connected by circuit conductors 26 and 27, respectively.

However, in the above configuration, the inductor parts and capacitor parts are larger in size than other high-frequency parts, and the height dimension in particular hinders miniaturization and thinning of the device.

The inductance of an inductor component tends to shift due to mechanical vibration, and since the ferrite core has a large temperature dependence, the inductance is unstable and the tuning frequency fluctuates greatly.

The inductor component and capacitor component exist as separate components and are connected by a conductor routing circuit, resulting in a large amount of lead inductance and stray capacitance, making the circuit operation unstable.

Since a tuner is a collective circuit of individual parts with independent minimum unit functions, there are limits to reducing the number of parts and rationalizing manufacturing.

Furthermore, the control voltage for the voltage variable capacitance diode is unstable, thus significantly degrading the tuning accuracy.

It is not possible to respond to the industrial trend of digitization and LSI as control system configuration technology, and it is not possible to realize advanced multi-functional control of the starting device and the equipment that uses it.

Furthermore, tracking errors occur due to deterioration in tuning accuracy and fluctuations in tuning frequency, which significantly reduces the sensitivity of the receiver. Furthermore, the filtering performance of the proximity interference signal is deteriorated, and the intermodulation interference rejection characteristics, image interference rejection characteristics, and spurious interference rejection characteristics are significantly deteriorated.

It had the following problems.

OBJECT OF THE INVENTION The object of the present invention is to realize a tuned circuit block in which an inductor part and a capacitor part are integrated, and to make it possible to control the tuning frequency of a tuner device including a plurality of integrated tuned circuit blocks by a digital signal. The goal is to make the form of the tuned circuit block ultra-thin and compact.
Furthermore, it is stable against mechanical vibrations, improves the tuning accuracy of the tuning frequency, has little temperature dependence of the tuning frequency, eliminates the negative effects of connection leads, is stable at high frequencies, and is manufactured with a reduced number of parts. This is to enable process rationalization.

Structure of the Invention The tuner device of the present invention is arranged such that the ground terminals of the electrodes that are disposed opposite to each other via a dielectric or arranged in parallel on the surface of the dielectric are set in opposite directions to each other. A plurality of tuning parts each having a voltage variable reactance element connected between required terminals of any one of the electrodes are installed, and a D-A converter is connected to the voltage variable reactance element of at least one or more of the first tuning parts. A second control section comprising a PLL circuit that supplies an analog output voltage of a first control section, and includes a variable frequency divider to at least one other voltage variable reactance element of a second tuning section. It is configured to supply a control output voltage and share a tuning control input terminal for each of the D-A converter and the variable frequency divider, so that one of the opposing electrodes acts as a distributed inductor. Moreover, by facing this electrode and the other electrode, a distributed constant circuit with an open tip is formed, thereby realizing distributed capacitance due to the generated negative reactance, and acting in parallel with the above-mentioned distributed inductor. A tuner device is configured with a plurality of tuned circuits based on the above, and the output voltage of the D-A converter and the tuning control output voltage of the PLL circuit are used as the control voltages of the voltage variable reactance elements connected to each of the tuned circuits. In this system, a digital code which is a tuning control signal is set and the tuning frequency is variably controlled. Further, the tuning control digital code is arbitrarily processed so that the tuning frequency of each tuner with respect to the tuning control digital code can be arbitrarily finely set.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 3 shows a circuit diagram of a first tuner constituting the main part of the tuner device in the embodiment of the present invention. 28 is a transmission line electrode that acts as a distributed inductor, 29 is a transmission line electrode 28
This is a transmission line electrode that is placed opposite to the transmission line electrode via a dielectric (not shown) and generates a distributed capacitor.
The respective transmission line electrodes 28 and 29 are grounded in opposite directions to form a parallel circuit 30 of an inductor and a capacitor. A voltage variable capacitance diode 32 is connected to the open terminal 31 of the transmission line electrode 29, and a tuner 33 is connected to the open terminal 31 of the transmission line electrode 29.
Configure. D- is connected to the voltage variable capacitance diode 32 via a resistor 34 for blocking AC signals.
The analog output voltage of the A converter 35 is supplied. A digital signal code for tuning control is input to an input terminal 36 of the DA converter 35.

FIG. 4 shows a circuit configuration diagram of an oscillation circuit section including a second tuner, which constitutes a main part of a tuner device in an embodiment of the present invention. 37 is a transmission line electrode that acts as a distributed inductor; 38
is a transmission line electrode that is placed opposite to the transmission line electrode 37 via a dielectric (not shown) and generates a distributed capacitor. Respective transmission line electrodes 37 and 3
By setting the ground terminals 8 in opposite directions, a parallel circuit 39 of an inductor and a capacitor is formed. A voltage variable capacitance diode 41 is connected to the open terminal 40 of the transmission line electrode 38 to constitute a tuner 42 . The voltage variable capacitance diode 41 is supplied with the output voltage of a low-pass filter 45 of a PLL circuit 44 via a resistor 43 for blocking AC signals. On the other hand, the tuner 42
Parallel circuit of inductor and capacitor in 39
The open terminal 40 of the transmission line electrode 39 is connected to a feedback amplifier 46 to form an oscillation circuit, and a part of the oscillation signal output from the feedback amplifier 46 is supplied to a fixed frequency divider 47 of a PLL circuit 44. The frequency is divided, and the frequency-divided output is further supplied to a variable frequency divider 48, where the frequency is variably divided according to a digital code inputted to an input terminal 49 for a digital tuning control signal. The divided output is the oscillation output of the crystal oscillator 50 and the phase comparator 51
, and the phase comparison detection signal is supplied to the low-pass filter 45.

FIG. 5 shows a block diagram of the configuration circuit of a tuner device according to an embodiment of the present invention. 52,
53 is the same tuner as the tuner 33 explained in FIG. 3, and further includes resistors 54, 55 and D
The configurations of the -A converters 56 and 57 are also the same as the connection configurations explained in FIG. 3 above. On the other hand 5
Reference numeral 8 is the same as the tuner 42 explained in FIG. 4 above, and the configurations of the PLL circuit 59 and the feedback amplifier 60 are also the same as the connection structure explained in FIG. 4 above. The signal input to the input terminal 61 is amplified by an amplifier 62 and supplied to a mixer 63, while the local oscillation signal is oscillated by an oscillation section consisting of a tuner 58, a PLL circuit 59, and a feedback amplifier 60. The signal is also supplied to the mixer 63, where it is mixed with the amplified signal described above and output as an intermediate frequency signal to the output terminal 64. and each tuner 52,5
The tuning frequencies of 3 and 58 are variably controlled by the setting of the tuning control digital signal code inputted to the common input terminal 65 for tuning control of the respective DA converters 56 and 57 and the PLL circuit 59.

FIG. 6 shows a circuit block diagram of a tuner device according to another embodiment of the present invention. The configuration of the tuners 52, 53, 58 and the connection configuration of the D-A converters 56, 57, the PLL circuit 59, the feedback amplifier 60, the amplifier 62, the mixer 63, and the resistors 54, 55 are shown in FIG. Same as described. On the other hand, the D-A converters 56, 57 and
If the PLL circuit 59 has a latch or a RAM or
Digital signal processor 65, 6 consisting of ROM
6 and 67 are prefixed and their outputs are supplied. The digital signal processors 65, 66, and 67 function to store a digital signal code for tuning control inputted to the common input terminal 68, or to convert it into a digital signal of another code. By installing digital signal processors 65, 66, and 67, it becomes possible to set and adjust the tuning frequency of each tuner 52, 53, and 58 to a required value, and tracking adjustment can be performed over the entire tuning frequency band. can be made complete.

FIG. 7 shows a circuit block diagram of a tuner device according to another embodiment of the present invention. The configurations of the tuners 52, 53, 58 are the same as those explained in FIG.
PLL circuit 59, feedback amplifier 60, resistors 54, 5
5 and digital signal processors 65, 66, 67
The connection configuration is also the same as that explained in FIG. 6 above. On the other hand, digital signal processors 65, 6
6 and 67 are provided with code converters 68, 69, and 70 for converting serial digital signal codes into parallel digital signal codes, and their outputs are supplied. This code converter 68,6
By installing terminals 9 and 70, the common input terminal 7
The digital signal for tuning control inputted to 1 can be transmitted via a single line, which simplifies the wiring and has the effect of saving wires.

FIGS. 8 to 15 show examples of parallel circuits 30 and 39 of inductors and capacitors in the tuner 33 and tuner 42 described in FIGS. 3 and 4, respectively. In FIG. 8, a shows a front view, b shows a side view, and c shows a back view. (hereinafter No. 9
(Similarly in Figures 1 to 15) In Figure 8, 100 is a dielectric substrate, and 101 and 102 are electrodes forming a distributed constant circuit to realize a distributed inductor and a distributed capacitor. Electrodes 101 and 10
As shown in Fig. 8, the ground terminals of No. 2 are set so that they are on the opposite sides of the opposing electrodes (hereinafter the same applies in Figs. 9 to 15), on the A side shown in Fig. 8a, B and A shown in Figure 8c.
Side and B correspond to each other. (The same applies to FIGS. 9 to 15 below) In FIG.
Electrodes 104 and 105 having bent portions are placed opposite each other.

In FIG. 10, electrodes 107 and 108 each having a plurality of bent portions are placed facing each other with a dielectric substrate 106 in between.

In FIG. 11, meander-shaped electrodes 110 and 111 are placed facing each other with a dielectric substrate 109 in between.

In FIG. 12, spiral-shaped electrodes 113 and 114 are placed facing each other with a dielectric substrate 112 in between.

In FIG. 13, electrodes 116 and 117 are installed on the surface of a dielectric substrate 115, facing each other laterally.

In FIG. 14, electrodes 119 and 120 are provided inside a dielectric substrate 118, facing each other.

In FIG. 15, an electrode 122 is installed inside a dielectric substrate 121, an electrode 123 is installed on the surface of the dielectric substrate 121, and the electrodes 122 and 123 are opposed to each other.

In the embodiments shown in FIGS. 8 to 15, the electrodes installed opposite each other had the same shape and completely faced each other on the entire surface. However, even if any one electrode has a different equivalent length than the other electrode, This can also be achieved by having the partner electrodes partially face each other. Further, the shapes of the electrodes used in the embodiments shown in FIGS. 13 to 15 can also be realized using the shapes shown in the embodiments shown in FIGS. 9 to 12.

In each of the above embodiments, the one shown in FIG. 8 can be constructed with a simple electrode pattern, and the one shown in FIGS. 9 to 12 has a relatively large distributed inductance and distributed capacitance with a small tuner occupation area. Therefore, a tuner with a relatively low tuning frequency can be constructed, and the one shown in FIG. 13 can be easily constructed because the electrode is formed on only one side of the dielectric. The ones shown in Figures 14 and 15 can be used with multilayer boards, and since the electrodes are built in, the performance of the tuner is less affected by external factors and can be configured stably. It has characteristics.

Next, the operating principle of the tuner used in the tuner device of the present invention will be explained.

16a to 16e are equivalent circuits for explaining the operation of the tuner of the present invention. In FIG. 16a, each transmission line electrode 27 has an electrical length l and has its ground terminal set in opposite directions.
For the transmission line formed by 0,271,
The signal source 272 that generates the voltage e is the transmission line electrode 27
0 to supply a signal. As a result, a traveling wave voltage e _A is excited at the open terminal at the tip of the transmission line electrode 270. On the other hand, since the transmission line electrode 271 is disposed close to and opposite to the above transmission line electrode 270 or in parallel with it, a voltage is induced by mutual induction. Let e _B be the traveling wave voltage induced in the open terminal at the tip of the transmission line electrode 271.

Here, since the ground terminals of the transmission line electrodes 270 and 271 are set in opposite directions, the induced traveling wave voltage e _B has an opposite phase to the excited traveling wave voltage e _A. Since the tips of the transmission paths of the traveling wave voltages e _A and e _B are open, voltage standing waves are formed in the transmission path formed by the transmission path electrodes 270 and 271. Here, the voltage distribution coefficient indicating the distribution mode of the voltage constant pressure wave in the transmission line electrode 270 is K.
The voltage distribution coefficient at the transmission line electrode 271 can be expressed as (1-K).

Next, the potential difference V generated at any opposing portion of the transmission line electrodes 270 and 271 can be expressed as V=Ke _A -(1-K)e _B (1). Here, if each transmission line electrode 270 and 271 has the same electrical length l, then e _B = -e _A ...(2), so the potential difference V in the first equation is V = Ke _A + (1 -K) e _A = e _A ...(3). That is, a potential difference V can be generated in all parts where the transmission line electrodes 270 and 271 face each other.

Here, it is assumed that the transmission line electrodes 270 and 271 have an electrode width W (the thickness of the electrodes is thin), and are opposed to each other at a distance d with a dielectric material having a dielectric constant ε _s interposed therebetween. In this case, the capacitance C _O formed per unit length of the transmission path is C _O =Q/V=Q/e _A ...(4) Q=ε _p ε _s W・V/d=ε _p ε _s W・e _A /d ...(5), and therefore C _O =ε _p ε _s W/d ...(6).

Therefore, the transmission path shown in FIG. 16a becomes a transmission path including a distributed capacitor 273 of C _O determined by the formula 6 per unit length as shown in FIG. 16b. Furthermore, as shown in FIG. 16c, this transmission line is distributed by a distributed inductor component of the transmission line and a lumped inductor component generated by the bent shape of the transmission line, respectively, and a distributed capacitor 273 and integrated distributed inductors 277 and 278. It can be expressed equivalently as a constant circuit.

Next, the relationship between the formation of the distributed capacitor 273 and the electrical length l of the transmission path will be explained.
The characteristic impedance Z _O per unit length in a balanced mode transmission line as shown in Figure 17a is
It can be expressed by the equivalent circuit shown in Figure b. Its characteristic impedance Z _O is generally becomes. If the transmission path is lossless, then becomes. This assumption can be applied to many of the embodiments of the tuner of the present invention, and to simplify the explanation, the characteristic impedance Z _O
Use. The capacitance C _O in the eighth equation is the same as the capacitance C _O per unit in the transmission line found in the sixth equation. In other words, the characteristic impedance per unit length in the transmission line
Z _O is a function of the capacitance C _O , which is also a function of the permittivity ε _s of the dielectric material involved in the capacitor C _O , the width W of the transmission line electrodes and the installation spacing d of the respective transmission line electrodes.

As described above, the characteristic impedance per unit length in the transmission line is Z _O , the electrical length is l, and the equivalent reactance X generated at the terminal of the transmission line with the end open is X = -Z _O cotθ can be expressed as (9). Here, θ=2πl/λ...(10), and especially in the case of θ=O~π/2 θ=π~3/4π...(11), the equivalent reactance X is X≦O...(12) becomes. In other words, the equivalent reactance at the terminal of the transmission line can be the capacitive reactance. Therefore, depending on the electrical length l of the transmission path, θ becomes the
When formula 11 is satisfied, for example, a capacitor can be formed by setting the electrical length l to λ/4 or less. And the capacitance C of the capacitor that can be formed is As expressed by , any capacitance C can be realized by changing θ, that is, by setting the electrical length l of the transmission path.

FIG. 18 is a diagram illustrating the operation mode of the transmission line explained in Equations 9 to 13 below. FIG. 17 shows how the equivalent reactance X generated at the terminal changes in accordance with the change in the electrical length l of the transmission line with its tip in an open state. As is clear from Fig. 18, the electrical length l of the transmission line is λ/4 or less or λ/2 ~
In cases such as at 4λ/3, it is possible to form a negative terminal reactance, ie equivalently to form a capacitor.
Further, by arbitrarily setting the electrical length l of the transmission path under conditions that generate negative terminal reactance, it is possible to realize the capacitance C to an arbitrary value.

The capacitor C thus formed is a lumped constant capacitor 279 shown in FIG. 16d.
can be equivalently replaced as . and,
The inductor formed by the sum of the distributed inductor component existing in the transmission line and the lumped inductor component generated by bending the transmission line can be equivalently replaced as the lumped constant inductor 280. If the ground terminal is shown in common in FIG. 16d, the final result will be a lumped constant capacitor 279 and a lumped constant inductor 280, as shown in FIG. 16e.
It is equivalent to a parallel resonant circuit consisting of the following, and can realize a tuner.

Although the configuration and operation described above realize the tuner of the present invention, the configuration of the tuner of the present invention and its operating principle are completely different from those of conventional tuners.
Therefore, in order to prove that the tuner according to the present invention is completely different from conventional tuners or those having other configurations even if they use the same transmission line as the tuner of the present invention. To,
The construction and operation of conventional tuners or tuners with other transmission line configurations will now be described and contrasted. This clarifies the difference from the tuner according to the present invention and also clarifies the novelty of the tuner according to the present invention.

FIG. 19 shows the operation when the transmission line electrodes are formed of the same material as used in the tuner of the present invention, but the difference is that the ground terminals are set in the same direction. be.
In FIG. 19a, transmission line electrodes 281 and 28
It is assumed that an open-ended transmission line consisting of 2 is driven by a signal source 283 that generates voltage e. As a result, a standing wave voltage e _A is excited at the open terminal at the tip of the transmission line electrode 281, and a standing wave voltage e _B is excited at the open terminal at the tip of the transmission line electrode 282, which is installed opposite or in parallel. shall be induced. Here, since the ground terminals of the transmission line electrodes 281 and 282 are set in the same direction, the standing wave voltages e _A and e _B are in phase with each other.
Therefore, the respective voltage distribution coefficients at transmission line electrodes 281 and 282 have the same K. As a result, the potential difference V at any part where the transmission line electrodes face each other becomes V=Ke _A −Ke _B (14). Here, if the electrical lengths of the respective transmission line electrodes 281 and 282 are the same length, e _A = e _B ... (15), so the potential difference V in Equation 14 is V = Ke _A - Ke _A =O...(16) In other words, no potential difference occurs in any part of the transmission path. FIG. 19b shows a configuration in which the signal source 283 in FIG. 19a is replaced at the end of the transmission line, and is equivalent to installing an unbalanced signal source 284 that generates voltage e'. In this equivalent circuit, there are only parallel transmission lines with no potential difference between them. In other words, it is clear that this is equivalent to the case where only one transmission line electrode 285 exists, as shown in FIG. 19c. Then, by equivalently replacing the signal source 283 and the ground terminal with the original circuit shown in FIG. 6a, the circuit shown in FIG. 19d is obtained. In other words, only an equivalent lumped constant inductor 286 is formed, which is composed of a distributed inductor component of the transmission line and a lumped inductor component generated by the curved shape of the transmission line. As is clear from the above, since a capacitor cannot be formed in parallel with an inductor, the intended parallel resonant circuit tuner cannot be realized.

Figure 20 shows a general microstrip line formed with the same transmission line electrode as that used in the tuner of the present invention as one side of the transmission line electrode, but the electrode facing the transmission line electrode has a sufficiently wide ground. This shows the operation when the curved points are different. In FIG. 20a, a transmission line electrode 287 faces a sufficiently wide ground electrode 288, is driven by a signal source 289 that generates a voltage e, and a standing wave voltage e _A is excited at the open terminal at the end of the transmission line. It is assumed that the voltage distribution coefficient K is the voltage distribution coefficient K. On the other hand, assuming that a standing wave voltage e _B having a voltage distribution coefficient K is virtually generated at the ground electrode 288, the transmission line electrode 287 and the ground electrode 28
The potential difference V at any part where 8 faces each other is expressed as: V=Ke _A −Ke _B (17). However, the standing wave voltage e _B at the ground electrode 288 is uniformly at the ground potential (zero potential), and e _B =O (18). Therefore, there is no voltage distribution coefficient at ground electrode 288 either. As a result, the potential difference V becomes V=Ke _A (19). This makes it possible to form a distributed capacitor between the transmission line electrode 287 and the ground electrode 288. However, the transmission line electrode 28
7 closely faces the ground electrode 288, the two ends of the transmission line electrode 287 are almost in a shot state due to mutual induction. Therefore, the Q performance of the inductor component in the transmission line electrode 287 is significantly degraded. That is, this microstrip line has an equivalent loss resistance of 290 as shown in FIG. 7b.
A parallel resonant circuit is formed by a lumped constant inductor 291 and a lumped constant capacitor 292, respectively. Here, since the equivalent loss resistance 290 actually has a considerably large resistance value, the loss in the resonant circuit becomes very large. Therefore, it is obvious that only a tuner with very low Q performance can be realized, and is not suitable for practical use.

FIG. 20 shows the circuit configuration of a λ/4 resonator, which is most commonly used in the conventional example, and the settings of the end conditions and the length of the transmission path,
Furthermore, it is shown that the tuner of the present invention is completely different from the tuner of the present invention in each point regarding the grounding setting. In FIG. 20, the balanced mode transmission line electrodes 293 and 294 have an electrical length l set equal to λ/4 at the resonance frequency, and have shortened ends. and a balanced signal source 2 that generates a voltage e
95, each transmission line electrode is driven in a balanced mode. The ground terminal is set at the neutral point of the balanced signal source 295, and does not specifically ground any terminal in the transmission line electrode. In this case, the equivalent terminal reactance X generated at the terminal of the transmission line is:
If the characteristic impedance of the transmission line is _ZO , then X= _ZO tanθ...(20). Here, the characteristic impedance Z _O is the same as that shown in the 8th equation, and θ is also the same as that shown in the 10th equation. In this resonator, the electrical length l of the transmission path is |=λ/4...(21), so θ=π/2...(22). Therefore, _the terminal reactance X in Equation 20 is as follows: However, when comparing the configuration of this λ/4 resonator with the configuration of the tuner of the present invention, first of all, looking at the terminal conditions of the transmission line, the tuner of the present invention is in an open state, whereas the conventional tuner has an open state. It is clear that the λ/4 resonator is in a shot state, and therefore has a completely different configuration in terms of terminal conditions. Furthermore, regarding the setting of the electrical length l of the transmission line, in the tuner of the present invention, it is set to λ/4 or less of the tuning frequency, and in practice it is set to a very short value of about λ/16. However, the conventional λ/4
In the resonator, the resonant frequency is strictly set to λ/4, and it is therefore clear that the configuration is fundamentally different in setting the electrical length l of the transmission path. Also, the electrical length l of the transmission path in the configuration
Due to the difference in λ/
In the case of four resonators, it is necessary to provide a very long transmission path, which has the disadvantage of increasing the size. Conventional λ/
4.In order to downsize the resonator, there are some cases in which the length of the transmission path is shortened by interposing a dielectric material with a very high permittivity, but the dielectric material with a high permittivity used for this purpose generally has a dielectric loss tanδ. It is very large, and therefore has the disadvantage that the Q performance as a resonator is significantly reduced. Furthermore, the temperature dependence of the dielectric constant of a dielectric material having a high dielectric constant is generally large, and therefore there is also the disadvantage that it is difficult to ensure the stability of the resonant frequency.

Next, in order to clarify the superiority of the performance of the tuner of the present invention, experimental results will be shown and explained in comparison with the performance of a conventional tuner. FIG. 22 is a graph showing the experimental results of measuring the temperature dependence of the tuning frequency. FIG. 23 is a graph showing the experimental results of measuring the temperature dependence characteristics of resonance Q. In FIGS. 22 and 23, characteristic A is the temperature dependence of the tuner according to the present invention, and is an experimental result when an alumina ceramic material or a resin-based printed circuit board is used as the dielectric material. On the other hand, characteristic B is as shown in FIG.
This is the temperature-dependent characteristic of the tuner most commonly used in the past. From these experimental results, it is clear that in the tuner of the present invention, even if it is constructed using a general dielectric material, the tuner frequency is extremely stable, and furthermore, the resonance Q is high and stable. . On the other hand, in conventional tuners, the tuning frequency and It was difficult to ensure the stability of resonance Q. Thereby, other temperature compensation components or other self-stabilizing compensation circuits were added to compensate for the instability.

The operation of the tuner used in the tuner device of this embodiment configured as described above will be described below. FIG. 24 shows an operational equivalent circuit of the tuner. In FIG. 24a, the grounding of electrodes 124 and 125, which are placed opposite each other with a dielectric (not shown) interposed therebetween, is set in opposite directions, and a voltage variable capacitance element 127 is connected to an open terminal 126 of electrode 124. A basic circuit is formed as follows. When an AC signal is applied to the open terminal 126 at this point, the ground terminals of the electrodes 124 and 125 are set in opposite directions, so the AC currents driven to the respective electrodes 124 and 125 have opposite phases to each other. Therefore, electrodes 124 and 1
A distributed capacitance can be generated between 25 and 25. This situation is shown in FIG. 24b, where the distributed capacitor 128 is formed and the inductive component of the electrode 125 shown in FIG. 22a is canceled out, making it equivalent to the ground plane 129. There is a distributed inductance in the electrode 124 and the 24th
As shown in FIG. c, a distributed inductor 130 is formed and a distributed capacitor 128 constitutes a distributed constant circuit. If this is equivalently converted into a lumped constant circuit, a parallel resonant circuit of the inductor 131, capacitor 132, and voltage variable capacitance element 127 will be constructed. and a control terminal 133 of the voltage variable capacitance element 127.
The tuning frequency of this tuner can be variably controlled by changing the tuning control voltage applied to the tuner.

The operation of a tuner device in an embodiment of the present invention including a tuner configured as shown in FIGS. 3 and 4 will be described below, with the tuner device shown in FIG. 7 as a representative example. A tuning control signal in the form of a serial digital signal code supplied to the input terminal 71 is converted into a parallel digital signal code by code converters 68, 69, and 70, and is input to digital signal processors 65, 66, and 67. . When latches are used as the digital signal processors 65, 66, and 67, the digital signal codes input thereto are temporarily stored as they are, and stored in the RAM.
Alternatively, if a ROM is used, the digital signal code is arbitrarily converted according to the stored contents written in advance. The digital signal code processed by either of them is sent to the D-A converter 5.
6, 57 to obtain an analog output voltage corresponding to the digital signal code, and the analog output voltage is also supplied to the voltage variable capacitance element 32 in FIG. It is also supplied to a frequency divider (variable frequency divider 48 shown in FIG. 4), and an analog output voltage corresponding to the digital signal code is obtained from a low-pass filter (low-pass filter 45 shown in FIG. 4). is supplied to variable capacitance element 41 in FIG. By changing the serial digital signal code input to the input terminal 71 in this manner, the tuning frequency of each tuner 52, 53, 58 can be variably set correspondingly. Other tuner devices in the embodiment shown in FIG. 5 include D-A converters 56 and 57.
A parallel format digital signal code is directly supplied to the common input terminal 65 of the PLL circuit 59, and the tuner device in the embodiment of FIG. It directly supplies digital signals. The tuner devices of the embodiments shown in FIGS. 5 to 7 all have respective tuners 52, 53, and
It operates to variably set the tuning frequency of 8. Here, the tuner electrode 14 (the third
Distribution generated in the parallel circuit 30 (Fig. 3) and the parallel circuit 39 (Fig. 4) of the inductor and capacitor by cutting (not shown) the required portions of the electrode 37 (Fig. 4) and the electrode 37 (Fig. 4). It is possible to variably set the capacitance of the capacitor, and the tuning frequency band can be set arbitrarily.

In this way, in various codes that can be set as digital signals for tuning control, it is possible to improve the setting accuracy of the tuning frequency of each tuner for all digital signal codes, and to improve the tuning frequency between each tuner. The relevance of the information can be ensured with high precision.

In the configuration of the tuner of the tuner device in each of the above embodiments, the voltage variable capacitance element is connected to the open terminal of the optical end of the electrode, but the desired purpose can be achieved even if it is connected to the terminal of any part of the electrode. . In addition, the electrodes of the tuner in each of the above embodiments include metal conductors, printed conductors,
Alternatively, a thin film conductor can be used, and alumina ceramic, plastic, Teflon, glass, mica, etc. can be used as the dielectric substrate.

In addition, the desired purpose can be achieved even if the digital signal processor and code converter are installed in common for any number of units in each tuner (not shown), streamlining the circuit configuration. can do.

Effects of the Invention As is clear from the above description, the present invention forms a tuning section with electrodes that face each other via a thin dielectric layer or are arranged in parallel on the surface of a dielectric, and tunes an added voltage variable reactance element. Since the control voltage is varied by a digital signal code and the digital signal code is arbitrarily converted by a digital signal processor and a code converter, it can be used as an inductor component of a tuner with a simple configuration. Capacitor parts can be integrated.

An ultra-thin and compact tuner can be realized.

Since the inductor, inductor, and capacitor of the tuner are connected in a leadless manner, there is no influence of the lead inductor or the stray capacitor, and therefore the operation of the tuner device is extremely stable and the tuning accuracy is improved.

It is possible to reduce the number of parts in the tuner, which enables rationalization of manufacturing and cost reduction.

Tuning control method using digital signal code, stable D-A converter conversion function, and reliable
The frequency lock function of the PLL circuit makes it possible to obtain a very stable tuning control voltage.
The tuning accuracy of the tuner device can be significantly improved.

It is possible to connect to a computer-applied multifunctional digital control system, and it is possible to realize advanced multifunctional control of the tuner device.

Tuner settings can be adjusted extremely finely by arbitrarily converting digital signal codes using a digital signal processor and by cutting tuner electrodes.
It becomes possible to completely eliminate tracking errors in the tuner device.

Thereby, it is possible to completely eliminate a decrease in sensitivity due to improper adjustment of the tuner device. In addition, it is possible to stably reproduce the filtering performance, and it is possible to stably ensure the suppression performance of intermodulation interference, image interference, spurious interference, etc. due to proximity interference signals over a long period of time.

This excellent effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a conventional tuner device, Fig. 2 is a perspective view of the configuration of a tuner used in the conventional tuner device, and Figs. 5 to 7 are the configuration circuit diagrams of the tuner device in the embodiment of the present invention, and FIGS. 8 to 1
Fig. 5 is a block diagram of a tuner used in the tuner device of the present invention, in which a is a front view, b is a side view, c is a back view, Figs. 16 a to e, Figs. 17 a and b, and Fig. 18. The figures are explanatory diagrams showing the operating principle of the tuner used in the tuner device of the present invention, Figures 19a to 19.
d, Fig. 20a, b, and Fig. 21 are explanatory diagrams showing the operating principle of a conventional tuner, Fig. 22, and Fig. 23.
FIG. 24 is a characteristic diagram of the tuning frequency and resonance Q with respect to temperature changes of the present invention and the conventional tuner, and FIG. 24 is a diagram illustrating the operating principle of the tuner used in the CHUE device in the embodiment of the present invention. 28, 29, 37, 38, 101, 104, 1
05, 107, 108, 110, 111, 11
3,114,116,117,119,120,
122, 123, 124, 125... Electrode, 3
2, 41, 127... Voltage variable capacitance element, 33, 42, 37, 52, 53, 58... Tuner, 35, 56, 57... D-A converter,
65, 66, 67...digital signal processor, 6
8, 69, 70... code converter, 62... amplifier, 63... mixer, 59... PLL circuit, 60
...Return magnifier.

Claims (1)

[Claims] 1. The terminals connected to the ground of the electrodes that are placed opposite to each other with a dielectric interposed therebetween or that are arranged side by side on the surface of the dielectric are in a positional relationship in which they are different from each other and do not face each other. A variable frequency oscillation section including a variable tuning section is installed, and a variable frequency oscillation section including a variable tuning section formed by connecting a voltage variable reactance element to a predetermined terminal of one electrode of each of the above electrodes, and further a variable frequency divider, a phase comparator, and a reference oscillator. , including low-pass filter
A control section comprising a PLL circuit is installed, and the oscillation output of the variable frequency oscillation section is input to the variable frequency divider, and the tuning control output voltage of the low-pass filter is supplied to the voltage variable reactance element. tuner device. 2. The tuner device according to claim 1, wherein the electrode has at least one bending portion exhibiting a predetermined bending angle or bending rate and a predetermined bending direction. 3. The tuner device according to claim 1, wherein the electrode has a spiral shape. 4. The tuner according to any one of claims 1 to 3, wherein the length of one electrode is set shorter than the length of the other electrode, and the tuner is arranged oppositely or in parallel at a predetermined part. Device. 5. The tuner device according to any one of claims 1 to 4, wherein each electrode or a portion or all of one of the electrodes is installed inside the dielectric. 6. The tuner device according to any one of claims 1 to 5, wherein the respective electrodes are installed on the inner circumference or the outer circumference of a cylindrical or prismatic dielectric body.