JP2003133818A - Dielectric resonator, dielectric filter, and dielectric duplexer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric resonator which can change resonance frequency accurately without being equipped with an external capacitor. SOLUTION: A coaxial dielectric resonator 2 constituting this dielectric resonator comprises a dielectric block 21 where a through hole 22 is opened, an outer conductor layer 24 which is made at the outside periphery of the dielectric block 21, an inner conductor layer 23 which is made at the inside periphery of the through hole 22 of the dielectric block 21, a short circuit conductor layer 25 which short-circuits the outer conductor layer 24 and the inner conductor layer 23 with each other, being made at one end face of the dielectric block 21, and an isolated conductor layer 3 which is made at the outside periphery of the dielectric block 21, being electrically isolated from the outer conductor layer 24. The isolated conductor layer 3 is connected to a ground via a switch, and the resonance frequency is changed by changing the capacity of the coaxial dielectric resonator 2 by the changeover of the switch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric resonance device, a dielectric filter and a dielectric duplexer used for communication equipment, video equipment and the like.

[0002]

2. Description of the Related Art Conventionally, in a terminal of a mobile communication system using a frequency band of several hundred MHz to several GHz,
As shown in FIG. 35, the duplexer (72) is attached to the antenna (7).
The receiving circuit (52) and the transmitting circuit (62) are connected in parallel via the one antenna (7) to form the receiving circuit (52) and the transmitting circuit (62).
It is shared with. The duplexer (72) comprises a reception filter device (50) and a transmission filter device (60), and each filter device (50) (60) uses, for example, the coaxial dielectric resonator (20) shown in FIG. It is configured.

As shown in FIG. 38, the coaxial dielectric resonator (20) has a through hole (22) formed in a rectangular parallelepiped dielectric block (21), and the dielectric block (21) has an outer peripheral surface and a through hole. The outer conductor layer (24) and the inner conductor layer (23) are respectively formed on the inner peripheral surface of the hole (22), and the outer surface is formed on one end surface of the dielectric block (21) where the through hole (22) opens. A short-circuit conductor layer (25) for short-circuiting the conductor layer (24) and the inner conductor layer (23) is formed. In the coaxial dielectric resonator (20), as shown in FIG. 39 (a), the outer conductor layer (24) is connected to the ground and the inner conductor layer (23) is connected to the signal input terminal S. . As a result, the coaxial dielectric resonator (20) becomes equivalent to a circuit in which the inductance element L and the capacitance element C are connected in parallel to each other as shown in FIG. 39 (b), and the inductance of the inductance element L and the capacitance of the capacitance element C are A trap filter having a resonance frequency determined by

By the way, in the mobile communication system, a terminal capable of supporting a plurality of communication systems having different frequency bands is required. Therefore, in order to change the transmission / reception frequency of the terminal according to the frequency band of each method, the reception filter device (50) and the transmission filter device (60) are provided with
7 shows a dielectric resonator device (for example, Japanese Patent Laid-Open No. 7-14750)
(See No. 3) is proposed. The dielectric resonance device has an external capacitor element C at the connection point between the inner conductor layer (23) of the coaxial dielectric resonator (20) and the signal input terminal S.
The switch SW is connected through 0, and the coaxial dielectric resonator (20) is formed by switching the opening and closing of the switch SW.
It is possible to connect or disconnect the capacitance C0 of the external capacitor element to the capacitance C formed between the outer conductor layer (24) and the inner conductor layer (23). The resonance frequency of the coaxial dielectric resonator (20) changes as the capacitance changes due to the switching of the switch SW.

FIG. 36 shows an example in which a reception filter device (50) and a transmission filter device (60) are constructed by using the above dielectric resonance device. As shown in the figure, the receiving filter device (50) includes a receiving side connecting terminal (51) to an antenna terminal (71).
A plurality of capacitance elements C4, C on the signal line extending to
5 and C6 intervene and transmit filter device (60)
Includes a plurality of capacitance elements C4 'and C5' on the signal line extending from the transmission side connection terminal (61) to the antenna terminal (71).
, C6 'are interposed, and two coaxial dielectric resonators (20), (20) are connected to both signal lines, respectively. A switch SW is connected to the connection point between each coaxial dielectric resonator (20) and the signal line via a capacitance element C0. Therefore, by switching these switches SW, the reception filter device (50) and the transmission filter device
By changing the passband of (60), the transmission and reception frequencies can be switched to two types.

[0006]

In recent years, mobile communication terminals such as mobile phones have been required to be further miniaturized, and reduction of the number of electric components and miniaturization have become major problems. However, in the dielectric resonance device shown in FIG. 37, since it is necessary to connect the chip-type external capacitor C0 to the coaxial dielectric resonator (20), the number of parts of the device increases and the size of the device increases. There was a problem. Further, since a chip-type capacitor has a large capacity tolerance, it is necessary to separately connect a circuit (not shown) for finely adjusting the capacity, which further increases the number of parts.

Therefore, an object of the present invention is to provide a dielectric resonator device capable of accurately changing the resonance frequency without mounting an external capacitor, a dielectric filter using the dielectric resonator device, and a dielectric filter. It is to provide a body duplexer.

[0008]

A dielectric resonator device according to the present invention comprises a coaxial dielectric resonator (2), said coaxial dielectric resonator.
(2) is a dielectric block (21) having a through hole (22)
And an outer conductor layer formed on the outer peripheral surface of the dielectric block (21).
(24), the inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21), and the through hole (22) of the dielectric block (21) is opened The outer conductor layer (2
4) and a short-circuit conductor layer (25) for short-circuiting the inner conductor layer (23) with each other,
On the outer peripheral surface of the dielectric block (21), there is provided a separation conductor layer (3) which is electrically separated from the outer conductor layer (24). A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and by switching the switch SW,
A capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) is connected to a capacitance C formed between the outer conductor layer (24) and the inner conductor layer (23), or It is possible to cut off and thereby change the resonance frequency of the coaxial dielectric resonator (2).

In the above dielectric resonator of the present invention,
For example, the inner conductor layer (23) of the coaxial dielectric resonator (2) is connected to the signal input terminal S, and the outer conductor layer (24) is connected to the ground. In the dielectric resonance device, the separation conductor layer (3) and the inner conductor layer (23) formed on the outer peripheral surface of the dielectric block (21) of the coaxial dielectric resonator (2) face each other, and A capacitance C'is formed between the layers, and the capacitance C'is connected to the capacitance C between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW, or Separated, it performs the same function as a conventional external capacitor.

In a specific configuration, a coaxial dielectric resonator
The separated conductor layer (3) of (2) is connected to the ground via the switch SW. Therefore, by closing the switch SW, the separation conductor layer (3) is connected to the ground,
As a result, the capacitance C ′ between the separation conductor layer (3) and the inner conductor layer (23) is connected to the capacitance C between the outer conductor layer (24) and the inner conductor layer (23), and the coaxial dielectric Body resonator
The resonance frequency of (2) shifts to the low frequency side. Further, by opening the switch SW, the separation conductor layer (3) is separated from the ground, and as a result, the separation conductor layer (3) and the inner conductor layer are separated.
The capacitance C'between (23) is the coaxial dielectric resonator.
The resonance frequency shifts to the high frequency side without being involved in the resonance frequency of (2).

In another specific structure, the separation conductor layer (3) of the coaxial dielectric resonator (2) has a groove (26) in the outer conductor layer (24) covering the outer peripheral surface of the dielectric block (21). Recess the outer conductor layer (2
It is formed by cutting off part of 4). Groove (2
6) can be formed by ultrasonic processing, for example, and the resonance frequency of the coaxial dielectric resonator (2) can be adjusted by finely adjusting the area of the separation conductor layer (3) when processing the groove (26). The design value can be matched with high accuracy.

In another specific configuration, the separation conductor layer
(3) is a first isolation conductor layer (31) electrically isolated from each other
And a second separated conductor layer (32), the first separated conductor layer
(31) is connected to the signal input terminal S, the second separation conductor layer (32) is connected to the ground via the switch SW,
The outer conductor layer (24) is connected to the ground. In this specific structure, a capacitance C'is formed between the second separation conductor layer (32) and the inner conductor layer (23), and the first separation conductor layer is formed.
A capacitance C ″ is formed between (31) and the inner conductor layer (23). Therefore, by inputting a high frequency signal to be input to the inner conductor layer (23) to the first separated conductor layer (31), The input signal passes through the capacitance C ″ and is input to the inner conductor layer (23). As a result, the input signal is transferred to the inner conductor layer.
No wire is needed to feed (23).

The dielectric filter according to the present invention includes a first dielectric resonator device (11) and a second dielectric resonator device at two positions on a signal line extending from the input terminal (42) to the output terminal (43). At least one of the dielectric resonators configured by connecting (12) includes the coaxial dielectric resonator (2) of the present invention. Separation conductor layer (3) of the coaxial dielectric resonator (2)
A switch SW is connected to the switch SW, and the capacitance C formed between the outer conductor layer (24) and the inner conductor layer (23) by switching each switch SW is different from the capacitance C formed between the outer conductor layer (24) and the inner conductor layer (23). 2
It is possible to connect or disconnect the capacitance C'formed during 3), thereby changing the signal passing characteristics.

The dielectric duplexer according to the present invention has an antenna terminal (71) to which the antenna (7) is to be connected,
The receiving filter device (5) and the transmitting filter device (6) are connected in parallel, and the receiving filter device (5) and the transmitting filter device (6) are respectively the coaxial dielectric resonator (2) of the present invention. ) Is included. The coaxial dielectric resonator
A switch SW is connected to the separated conductor layer (3) of (2), and the outer conductor layer (24) and the inner conductor layer are switched by switching each switch SW.
The capacitance C'formed between the separating conductor layer (3) and the inner conductor layer (23) is connected or disconnected with respect to the capacitance C formed between the receiving filter device (5). It is also possible to change the signal passing characteristics of the transmission filter device (6).

Another dielectric duplexer according to the present invention has a receiving filter device (54) and a transmitting filter device (6) for an antenna terminal (71) to which the antenna (7) is to be connected.
4) is connected in parallel with the receiving filter device (5
4) is configured by connecting in series a main filter circuit (82) having a pass band in the frequency band of the received signal and a trap circuit (83) for attenuating the frequency band of the transmitted signal,
The trap circuit (83) is the coaxial dielectric resonator of the present invention.
It has (2). A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. For the capacitance C, the capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) is connected or disconnected, whereby the reception filter device (54).
It is possible to change the signal passing characteristics of.

[0016]

In the dielectric resonator device, the dielectric filter and the dielectric duplexer according to the present invention, the coaxial dielectric resonator (2) itself has a capacitance for changing the resonance frequency. The resonance frequency can be changed without equipping an external capacitor. By finely adjusting the area of the separation conductor layer (3), the resonance frequency of the coaxial dielectric resonator (2) can be set with high accuracy.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 shows the structure of a dielectric resonance device (1) according to the present invention. The dielectric resonance device (1) includes a coaxial dielectric resonator (2) and a switch for changing a resonance frequency. It is equipped with SW.

As shown in FIGS. 2 and 3, the coaxial dielectric resonator (2) comprises a rectangular parallelepiped dielectric block (21) made of a ceramic material such as BaTiO ₃ , and the dielectric block (21). A through hole (22) is formed in the central part of the. The outer peripheral surface of the dielectric block (21) is covered with the outer conductor layer (24), and the inner peripheral surface of the through hole (22) is covered with the inner conductor layer (23). One end face of the dielectric block (21) where the through hole (22) is opened is covered with a short-circuit conductor layer (25) for short-circuiting the outer conductor layer (24) and the inner conductor layer (23).
Further, the outer conductor layer (24) covering the outer peripheral surface of the dielectric block (21) is provided with a groove (26) which circulates by ultrasonic machining or the like, and the outer conductor is provided inside the groove (26). A separated conductor layer (3) electrically separated from the layer (24) is formed.

In the dielectric resonator device (1) shown in FIG. 1,
The separation conductor layer (3) of the coaxial dielectric resonator (2) is a switch S.
It is connected to the ground via W. The switch SW
Can be configured using, for example, a diode.
The signal input terminal S is connected to the inner conductor layer (2) of the coaxial dielectric resonator (2).
It is connected to 3). The outer conductor layer (24) of the dielectric resonator device (1) is connected to the ground. 23 (a) (b)
Shows the dielectric resonator device (1) and its equivalent circuit. The inductance element L and the capacitance element C are connected in parallel with each other by connecting the terminal T connected to the separation conductor layer (3) to the ground. For the circuit, the capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) will be connected in series.

In the above dielectric resonator (1), the switch SW is closed to connect the separation conductor layer (3) to the ground, and as a result, the outer conductor layer (24) and the inner conductor layer (2).
The capacitance C'between the separation conductor layer (3) and the inner conductor layer (23) is connected to the capacitance C between the three, and the capacitance of the coaxial dielectric resonator (2) increases. Also, switch S
By opening W, the separation conductor layer (3) is separated from the ground, and as a result, the separation conductor layer (3) and the inner conductor layer (23)
The capacitance C ′ between them becomes non-functional, and the capacitance of the coaxial dielectric resonator (2) decreases. In this way, the capacitance of the coaxial dielectric resonator (2) is changed by switching the switch SW, whereby the resonance frequency of the coaxial dielectric resonator (2) can be changed. Therefore, it is not necessary to connect a conventional external capacitor.

Further, in the above-mentioned dielectric resonance device (1),
In the manufacturing process, after forming the outer conductor layer (24) covering the entire outer peripheral surface of the dielectric block (21), a groove (26) is formed in the outer conductor layer (24) by ultrasonic processing or the like. As a result, since the separated conductor layer (3) is formed, the area of the separated conductor layer (3) can be adjusted freely and with high accuracy when the groove (26) is processed. As a result, the resonance frequency of the coaxial dielectric resonator (2) can be accurately matched with a predetermined design value.

FIG. 4 shows an example of the structure of a dielectric filter having a trap circuit using the coaxial dielectric resonator (2). Input terminal (42) to output terminal as shown
The first inductance element L is connected to the signal line extending to (43).
The first dielectric element L2 and the third inductance element L3 are interposed, and the first dielectric element is provided at the connection point between the first inductance element L1 and the second inductance element L2 via the first capacitance element C1 for coupling. Resonator
(11) is connected, and the second dielectric resonance device (12) is connected to the connection point between the second inductance element L2 and the third inductance element L3 via the second capacitance element C2 for coupling.
Are connected. Each of the first dielectric resonance device (11) and the second dielectric resonance device (12) has the same configuration as the dielectric resonance device (1) shown in FIG.

The switch SW constituting the first dielectric resonance device (11) and the second dielectric resonance device (12) is composed of a diode D and a resistor R as shown in FIG. 8, and has a control terminal (44).
The switch SW can be opened and closed by switching the voltage applied to the switch.

5 to 7 show an example in which the dielectric filter is actually formed on the circuit board (4). On the circuit board (4), the input terminal (42) and the output terminal (4
3), the conductor pattern (40) including the control terminal (44) and the ground electrode pattern (45) is formed. In FIG. 7, the region where the ground electrode pattern (45) is formed is shown by hatching. As shown in FIG. 5, on the conductor pattern (40), the coaxial dielectric resonators (2) and (2), the first to the third conductors are arranged.
Inductance elements L1, L2, L3, first and second capacitance elements C1, C2, diodes D, D, and resistors R, R are arranged. Here, the both coaxial dielectric resonators (2) and (2) are fixed by contacting the surface on which the separation conductor layer is formed with the surface of the circuit board (4), respectively.
The conductor patterns extending from the second capacitance elements C1 and C2 are connected to the inner conductor layer (23) of the coaxial dielectric resonator (2) through the wires (41).

In the above dielectric filter, the voltage applied to the control terminal (44) is switched to simultaneously open and close the switches SW of the first dielectric resonance device (11) and the second dielectric resonance device (12). By both dielectric resonators (11) (12)
The resonance frequency of can be changed. In FIG. 12, the solid line indicates the signal pass characteristic when the switch SW is opened, and the broken line indicates the signal pass characteristic when the switch SW is closed. In this way, by switching the switch SW, the signal passing characteristic of the dielectric filter can be shifted to the low frequency side or the high frequency side.

FIG. 9 shows a constitutional example of another dielectric filter using the coaxial dielectric resonator (2). As shown in the figure, the signal line extending from the input terminal (42) to the output terminal (43) includes the first capacitance element C4, the second capacitance element C5, and the third capacitance element C6, and the first capacitance element C4 and the third capacitance element C4. The first dielectric resonance device (11) is connected to the connection point between the two capacitance elements C5, and the second dielectric resonance device (12) is connected to the connection point between the second capacitance element C5 and the third capacitance element C6. It is connected. The first dielectric resonance device (11) and the second dielectric resonance device (12) are respectively the dielectric resonance device shown in FIG.
It has the same configuration as (1).

FIG. 10 shows an example in which the dielectric filter is actually formed on the circuit board (4). Circuit board
In (4), input terminal (42), output terminal (43), control terminal (44)
And a conductor pattern (40) including the ground electrode pattern (45). The coaxial dielectric resonators (2) and (2) and the first to third capacitance elements C are provided on the conductor pattern (40).
4, C5, C6, diodes D, D, and resistors R, R are arranged. Here, both coaxial dielectric resonators (2) (2)
The circuit board (4)
It is fixed in contact with the surface of. The conductor pattern extending from the connection point between the first capacitance element C4 and the second capacitance element C5 is connected to the inner conductor layer (23) of the coaxial dielectric resonator (2) via the wire (41), The conductor pattern extending from the connection point between the capacitance element C5 and the third capacitance element C6 is connected to the inner conductor layer (23) of the coaxial dielectric resonator (2) via the wire (41).

In the above dielectric filter, the voltage applied to the control terminal (44) is switched to simultaneously open and close the switches SW of the first dielectric resonance device (11) and the second dielectric resonance device (12). By both dielectric resonators (11) (12)
The resonance frequency of can be changed. In FIG. 13, the solid line shows the signal pass characteristic when the switch SW is opened, and the broken line shows the signal pass characteristic when the switch SW is closed. In this way, by switching the switch SW, the signal passing characteristic of the dielectric filter can be shifted to the low frequency side or the high frequency side.

Further, FIG. 11 shows a structure of a dielectric duplexer constructed by using the above dielectric filter. As shown in the drawing, the receiving filter device (5) and the transmitting filter device (6) are connected in parallel to the antenna terminal (71), and the receiving filter device (5) and the transmitting filter device (6) are respectively , The dielectric filter shown in FIG. Also, the receiving filter device (5)
The connection point between the transmission filter device (6) and the transmission filter device (6) is connected to the ground via the fourth inductance L4, and unnecessary low frequency components are reduced by the fourth inductance L4.

In the above-mentioned dielectric duplexer, the signal passing characteristics of both filter devices (5) and (6) are changed by simultaneously switching the switches SW of the receiving filter device (5) and the transmitting filter device (6). Can be done. FIG. 14 shows the signal passing characteristics Rx-H and Tx-H of the reception filter device (5) and the transmission filter device (6) when the switch SW is opened by solid lines, and the reception filter device when the switch SW is closed. The signal passing characteristics Rx-L and Tx-L of (5) and the transmission filter device (6) are indicated by broken lines. As described above, the frequency band of the received signal and the transmitted signal can be shifted to the high frequency side or the low frequency side by switching the switch SW, so that the mobile communication terminal device compatible with two communication systems having different frequency bands. Can be configured.

FIG. 15 shows a dielectric resonator device according to the present invention.
2 shows another configuration of (1), wherein the dielectric resonator device (1)
Comprises a coaxial dielectric resonator (2) and a switch SW for changing the resonance frequency. Coaxial dielectric resonator
(2) is a rectangular parallelepiped dielectric block as shown in FIG.
The dielectric block (21) is provided with a through hole (22) at the center thereof. The outer peripheral surface of the dielectric block (21) is covered with the outer conductor layer (24), and the inner peripheral surface of the through hole (22) is covered with the inner conductor layer (23). Dielectric block (2
One end face where the through hole (22) of 1) opens is the outer conductor layer (24)
And the inner conductor layer (23) are covered by a short-circuit conductor layer (25). Further, the outer conductor layer (24) covering the outer peripheral surface of the dielectric block (21) is provided with a first groove (27) and a second groove (28) which circulate by ultrasonic processing or the like, Both grooves
Inside the (27) and (28), a first separation conductor layer (31) and a second separation conductor layer (32) that are electrically separated from the outer conductor layer (24) are formed.

In the dielectric resonator device (1) shown in FIG. 15, the second separation conductor layer (32) of the coaxial dielectric resonator (2) is connected to the ground via the switch SW. The signal input terminal S is connected to the first isolation conductor layer (3) of the coaxial dielectric resonator (2).
It is connected to 1). The outer conductor layer (24) of the dielectric resonator device (1) is connected to the ground. 24 (a) (b)
Shows the dielectric resonance device (1) and its equivalent circuit. By connecting the terminal T connected to the second separation conductor layer (32) to the ground, the inductance element L and the capacitance element C are parallel to each other. Second to the connected circuit
The capacitance C'formed between the separation conductor layer (32) and the inner conductor layer (23) and the capacitance C "formed between the first separation conductor layer (31) and the inner conductor layer (23) are Will be connected.

In the dielectric resonance device (1), the second separation conductor layer (32) is connected to the ground by closing the switch SW, and as a result, the outer conductor layer (24) and the inner conductor layer (23). ) Between the second isolation conductor layer
The capacitance C'between the (32) and the inner conductor layer (23) is connected to increase the capacitance of the coaxial dielectric resonator (2). Also, by opening the switch SW, the second separation conductor layer (32) is separated from the ground, and as a result, the second separation conductor layer (3
The capacitance C'between 2) and the inner conductor layer (23) does not function, and the capacitance of the coaxial dielectric resonator (2) decreases. In this way, the capacitance of the coaxial dielectric resonator (2) is changed by switching the switch SW, whereby the resonance frequency of the coaxial dielectric resonator (2) can be changed. Therefore, it is not necessary to connect a conventional external capacitor.

Further, in the above dielectric resonator (1),
As shown in FIGS. 24 (a) and 24 (b), a capacitance C'is formed between the second separated conductor layer (32) and the inner conductor layer (23), and at the same time, the capacitance C'is formed between the first separated conductor layer (31) and the inner conductor layer (31). Since the capacitance C ″ is formed between the conductor layers (23), the high-frequency signal to be input to the inner conductor layer (23) is input to the first separation conductor layer (31) so that the input signal has the capacitance. It passes through C ″ and is input to the inner conductor layer (23). As a result, the wire for supplying the input signal to the inner conductor layer (23) is unnecessary.

FIG. 17 shows an example of the structure of a dielectric filter using the coaxial dielectric resonator (2). As shown in the drawing, the signal line extending from the input terminal (42) to the output terminal (43) includes the first inductance element L1, the second inductance element L2, and the third inductance element L3,
The first dielectric resonance device (13) is connected to the connection point between the first inductance element L1 and the second inductance element L2, and the first dielectric resonance device (13) is connected to the connection point between the second inductance element L2 and the third inductance element L3. Two dielectric resonators (14) are connected. The first dielectric resonance device (13) and the second dielectric resonance device (14) are respectively the dielectric resonance device shown in FIG.
It has the same configuration as (1).

The switch SW constituting the first dielectric resonance device (13) and the second dielectric resonance device (14) is composed of a diode D and a resistor R, like the switch SW shown in FIG. The switch SW can be opened and closed by switching the voltage applied to 44).

18 to 20 show an example in which the dielectric filter is actually formed on the circuit board (4). As shown in FIG. 19, a conductor pattern (46) including an input terminal (42), an output terminal (43), a control terminal (44) and a ground electrode pattern (45) is formed on the circuit board (4). In FIG. 20, the area where the ground electrode pattern (45) is formed is shown by hatching. As shown in FIG. 18, the coaxial dielectric resonators (2) and (2), the first to third inductance elements L1, L2 and L3, the diodes D and D, and the resistors R and R are provided on the conductor pattern (46). Are arranged. Here, the both coaxial dielectric resonators (2) and (2) are fixed by contacting the surface on which the separation conductor layer is formed with the surface of the circuit board (4).

In the above dielectric filter, the voltage applied to the control terminal (44) is switched to simultaneously open and close the switches SW of the first dielectric resonance device (13) and the second dielectric resonance device (14). By both dielectric resonators (13) (14)
By changing the resonance frequency of the signal, the signal passing characteristic of the dielectric filter can be shifted to the low frequency side or the high frequency side.

In the above dielectric filter, since the structure shown in FIG. 24 (a) is adopted as the dielectric resonators (13) and (14), the input signal to the coaxial dielectric resonator (2) is input. It suffices to supply it to the first separated conductor layer (31), and as shown in FIG. 18, a wire for supplying an input signal to the inner conductor layer (23) is unnecessary. Further, as shown in FIGS. 24 (a) and 24 (b), a capacitance C ″ is formed between the first separation conductor layer (31) and the inner conductor layer (23) of the coaxial dielectric resonator (2). Since C ″ exerts the function of the coupling capacitance, the coupling capacitance elements C1 and C2, which were required in the dielectric filter shown in FIG. 4, are unnecessary in the dielectric filter shown in FIG.

FIG. 21 shows a constitutional example of another dielectric filter using the coaxial dielectric resonator (2). As shown in the figure, the signal line extending from the input terminal (42) to the output terminal (43) includes the first capacitance element C4, the second capacitance element C5, and the third capacitance element C6, and the first capacitance element C4 and the third capacitance element C4. The first dielectric resonance device (13) is connected to the connection point between the two capacitance elements C5, and the second dielectric resonance device (14) is connected to the connection point between the second capacitance element C5 and the third capacitance element C6. It is connected. The first dielectric resonance device (13) and the second dielectric resonance device (14) are respectively the dielectric resonance device shown in FIG.
It has the same configuration as (1).

FIG. 22 shows the structure of a dielectric duplexer constructed by using the above dielectric filter. As shown in the drawing, the receiving filter device (5) and the transmitting filter device (6) are connected in parallel to the antenna terminal (71), and the receiving filter device (5) and the transmitting filter device (6) are respectively , The dielectric filter shown in FIG. In the dielectric duplexer, by simultaneously switching the switches SW of the reception filter device (5) and the transmission filter device (6), the signal passing characteristics of both filter devices (5) and (6) are changed to the high frequency side or the low frequency side. Therefore, it is possible to configure a mobile communication terminal capable of supporting two communication systems having different frequency bands.

FIG. 25 shows a duplexer (7 according to the present invention.
It represents another configuration of 3). Antenna (7) as shown
In contrast, a transmission filter device (64) having a pass band in the frequency band of the transmission signal and an attenuation band in the frequency band of the reception signal, and a transmission filter device having a pass band in the frequency band of the reception signal and attenuation in the frequency band of the transmission signal A reception filter device (54) having a band is connected.

The transmission filter device (64) is constructed by connecting the switch SW to the coaxial dielectric resonator (2). On the other hand, the reception filter device (54) is a main filter circuit (82) having a pass band in the frequency band of the reception signal, a matching circuit (81), and a trap circuit (83) for attenuating the frequency band of the transmission signal. And are connected in series. The main filter circuit (82) is composed of a well-known surface acoustic wave filter (8) in which a comb-shaped input electrode and output electrode are formed on the surface of a LiTaO ₃ substrate, for example. The trap circuit (83) is a coaxial dielectric resonator.
The dielectric filter of the present invention is formed by connecting the switch SW to (2). Incidentally, the trap circuit (83)
As the coaxial dielectric resonator (2) constituting the above, as shown in FIG. 26, one having a single separation conductor layer (3), or
As shown in FIG. 27, it is possible to employ one having a first separation conductor layer (31) and a second separation conductor layer (32).

FIG. 28 shows a duplexer (7 according to the present invention.
It shows a concrete configuration example of 3). As shown in the figure, the receiving filter device (54) is a surface acoustic wave filter for the signal line extending from the receiving side connection terminal (51) to the antenna (7).
Main filter circuit (82) consisting of (8) and matching circuit (81)
And a trap circuit (83) of the present invention comprising a coaxial dielectric resonator (2) and a switch SW are connected.
On the other hand, the transmission filter device (64) has a transmission side connection terminal (61).
To the antenna (7), the dielectric resonator device of the present invention including the coaxial dielectric resonator (2) and the switch SW is connected to each of two positions on the signal line.

In the duplexer (73), the signal passing characteristics of the reception filter device (54) and the transmission filter device (64) are changed by switching the switches SW of the reception filter device (54) and the transmission filter device (64). It will be shifted. In the reception filter device (54),
Since the impedance of the main filter circuit (82) and the impedance of the trap circuit (83) are matched by the matching circuit (81), the signal passing characteristic of the reception filter device (54) is the same as that of the main filter circuit (82). It is a combination of the signal passing characteristic and the signal passing characteristic of the trap circuit (83).

FIG. 32 shows the signal passing characteristic of the reception filter device (54) when the switch SW is opened by a solid line. Further, FIG. 33 shows the signal passing characteristic of the reception filter device (54) when the switch SW is closed by a solid line.
32 and 33, the chain line represents the signal passing characteristic of the main filter circuit (82) which constitutes the reception filter device (54) alone.

Here, the duplexer (73) according to the present invention
Explain the effectiveness of. In mobile communication systems,
Many channels are included in the transmission pass band and the reception pass band. FIG. 34 shows a CDMA 19 as an example.
00 shows the transmission / reception band of the system. In this system, when receiving on the high channel (High Ch), it transmits on the high channel, and on the low channel (Lo
When receiving on Ch), it is transmitted on the low channel.

When performing transmission / reception on the high channel, the switch SW of the duplexer (73) is opened, whereby the suppression band of the trap circuit (83) is shifted to the high frequency side. As a result, as shown in FIG. 32, a signal pass characteristic in which the high channel band of the transmission band is sufficiently suppressed can be obtained. Therefore, there is no possibility that the high-channel transmission signal leaks to the receiving circuit. On the other hand, when performing transmission / reception in the low channel, the switch SW of the duplexer (73) is closed, which causes the suppression band of the trap circuit (83) to shift to the low frequency side. As a result, as shown in FIG. 33, within the transmission band,
A signal pass characteristic in which the low channel band is sufficiently suppressed can be obtained. Therefore, there is no possibility that the low-channel transmission signal leaks to the receiving circuit.

FIG. 29 shows a duplexer (7 according to the present invention.
It shows still another configuration example of 3). Here, the reception filter device (54) has the same configuration as the reception filter device (54) of the duplexer (73) of FIG. On the other hand, the transmission filter device (64) includes a dielectric resonator device including the coaxial dielectric resonator (2) of the present invention and a switch SW as the main filter circuit (84), and also has elasticity as the trap circuit (85). It is equipped with a surface wave filter (80). The same effect can be obtained by the duplexer (73).

Further, FIG. 30 shows another configuration example of the reception filter device (54). The reception filter device (54)
Comprises a trap circuit (83) of the present invention comprising a coaxial dielectric resonator (2) and a switch SW, and a plurality of coaxial dielectric resonators (9) constitute a main filter circuit (82). . The main filter circuit (82), the matching circuit (81) and the trap circuit (83) are integrated by using a common dielectric block (91) as shown in FIG. 31, and together with the diode D and the resistor R, Located on the circuit board (90). According to the reception filter device (54), the reception filter device (5
Since 4) is configured as one module, the man-hours for assembling the mobile communication terminal can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a dielectric resonance device according to the present invention.

FIG. 2 is a perspective view of a coaxial dielectric resonator that constitutes the dielectric resonance device.

FIG. 3 is a sectional view of the coaxial dielectric resonator.

FIG. 4 is a diagram showing a configuration of a dielectric filter of the present invention using the dielectric resonance device.

FIG. 5 is a perspective view showing a specific structure of the dielectric filter.

FIG. 6 is a perspective view of a circuit board used for the dielectric filter.

FIG. 7 is a plan view of the dielectric filter.

FIG. 8 is a circuit diagram showing a specific configuration of a switch.

FIG. 9 is a diagram showing another configuration of the dielectric filter according to the present invention.

FIG. 10 is a plan view showing a specific structure of the dielectric filter.

FIG. 11 is a diagram showing a configuration of a dielectric duplexer according to the present invention.

FIG. 12 is a graph showing signal passing characteristics of the dielectric filter shown in FIG.

FIG. 13 is a graph showing signal passing characteristics of the dielectric filter shown in FIG.

FIG. 14 is a graph showing signal passing characteristics of the dielectric duplexer shown in FIG.

FIG. 15 is a diagram showing another configuration of the dielectric resonant device according to the present invention.

FIG. 16 is a perspective view of a coaxial dielectric resonator that constitutes the dielectric resonance device.

FIG. 17 is a diagram showing a structure of a dielectric filter of the present invention using the dielectric resonator.

FIG. 18 is a perspective view showing a specific structure of the dielectric filter.

FIG. 19 is a perspective view of a circuit board used for the dielectric filter.

FIG. 20 is a plan view of the dielectric filter.

FIG. 21 is a diagram showing another configuration of the dielectric filter according to the present invention.

FIG. 22 is a diagram showing a configuration of a dielectric duplexer according to the present invention.

23 is a diagram showing an equivalent circuit of the coaxial dielectric resonator shown in FIG.

24 is a diagram showing an equivalent circuit of the coaxial dielectric resonator shown in FIG.

FIG. 25 is a diagram showing another configuration of the dielectric duplexer according to the present invention.

FIG. 26 is a diagram showing a configuration of a reception filter device that constitutes the dielectric duplexer.

FIG. 27 is a diagram showing another configuration of a reception filter device that constitutes the dielectric duplexer.

FIG. 28 is a diagram showing a specific configuration of the dielectric duplexer.

FIG. 29 is a diagram showing another specific configuration of the dielectric duplexer.

FIG. 30 is a diagram showing still another configuration of the reception filter device.

FIG. 31 is a perspective view showing a specific structure of the reception filter device.

FIG. 32 is a graph showing a signal pass characteristic of the reception filter device when the switch is opened.

FIG. 33 is a graph showing a signal passing characteristic of the reception filter device when the switch is closed.

FIG. 34 is a diagram illustrating a transmission / reception band in a CDMA1900 system.

FIG. 35 is a block diagram showing a configuration of a mobile communication terminal.

FIG. 36 is a diagram showing a configuration of a conventional reception filter device and transmission filter device.

FIG. 37 is a diagram showing a configuration of a conventional dielectric resonator device.

FIG. 38 is a perspective view showing the structure of a conventional coaxial dielectric resonator.

FIG. 39 is a diagram showing an equivalent circuit of a conventional coaxial dielectric resonator.

[Explanation of symbols]

(1) Dielectric resonance device (11) First dielectric resonator (12) Second dielectric resonator (13) First dielectric resonator (14) Second dielectric resonator (2) Coaxial dielectric resonator (21) Dielectric block (22) Through hole (23) Inner conductor layer (24) Outer conductor layer (25) Short-circuit conductor layer (26) Groove (27) First groove (28) Second groove (3) Separate conductor layer (31) First separated conductor layer (32) Second separated conductor layer SW switch (4) Circuit board (40) Conductor pattern (42) Input terminal (43) Output terminal (44) Control terminal (5) Reception filter device (6) Transmission filter device (73) Duplexer (8) Surface acoustic wave filter (9) Coaxial dielectric resonator

Continued front page    (72) Inventor Masahisa Nakaguchi             1-1 Sanyo-cho, Daito-shi, Osaka Sanyo Electronics Department             Product Co., Ltd. (72) Inventor Hiroyuki Taguchi             1-1 Sanyo-cho, Daito-shi, Osaka Sanyo Electronics Department             Product Co., Ltd. F term (reference) 5J006 HA03 HA15 HA25 HA33 JA01                       JA02 JA06 JA12 KA01 KA11                       LA11 MA08 MA12 NA04 NC03                       PB03

Claims (15)

[Claims] 1. A dielectric resonator device comprising a coaxial dielectric resonator (2), wherein the coaxial dielectric resonator (2) comprises a dielectric block (21) having a through hole (22) formed therein. And the outer conductor layer (24) formed on the outer peripheral surface of the dielectric block (21).
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other, And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. A dielectric for connecting or disconnecting a capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) with respect to the capacitance C, thereby changing the resonance frequency of the coaxial dielectric resonator (2). Body resonance device. 2. A separation conductor layer (3) of a coaxial dielectric resonator (2).
Is connected to the ground via the switch SW, and the dielectric resonator device according to claim 1, wherein connection / disconnection of the isolation conductor layer (3) to / from the ground is performed by switching the switch SW. 3. A separation conductor layer (3) of a coaxial dielectric resonator (2).
Is formed by forming a groove (26) in the outer conductor layer (24) covering the outer peripheral surface of the dielectric block (21) and separating a part of the outer conductor layer (24). Alternatively, the dielectric resonance device according to claim 2. 4. The inner conductor layer (23) of the coaxial dielectric resonator (2) is connected to the signal input terminal S, and the outer conductor layer (24) is connected to the ground. 3. The dielectric resonator device according to any one of 3 above. 5. The separation conductor layer (3) is composed of a first separation conductor layer (31) and a second separation conductor layer (32) which are electrically separated from each other, and the first separation conductor layer (31). 5. The second separation conductor layer (32) is connected to the ground via the switch SW, and the outer conductor layer (24) is connected to the ground. 2. The dielectric resonance device according to any one of 1. 6. A first dielectric resonator device (1) is provided at each of two positions on a signal line extending from an input terminal (42) to an output terminal (43).
1) and the second dielectric resonance device (12) are connected to each other, and at least one of the dielectric resonance devices is a coaxial dielectric resonator.
The coaxial dielectric resonator (2) comprises a dielectric block (21) having a through hole (22) and an outer conductor layer formed on the outer peripheral surface of the dielectric block (21). (twenty four)
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other and the outer conductor layer (24) on the outer peripheral surface of the dielectric block (21). And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. A dielectric filter for connecting or disconnecting a capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) with respect to the capacitance C, thereby changing the signal passing characteristic. 7. A signal line extending from an input terminal (42) to an output terminal (43) includes a first inductance element L1, a second inductance element L2, and a third inductance element L3, and is connected to the first inductance element L1. The first capacitance element C is provided at a connection point between the second inductance elements L2.
To the connection point between the second inductance element L2 and the third inductance element L3 via the second capacitance element C2.
The dielectric filter according to claim 6, wherein a dielectric resonance device (12) is connected. 8. A separation conductor layer (3) for a coaxial dielectric resonator (2).
Is composed of a first separation conductor layer (31) and a second separation conductor layer (32) which are electrically separated from each other. The first separation conductor layer (31) is connected to the signal input terminal S, and 2 Separate conductor layer (3
The dielectric filter according to claim 6, wherein 2) is connected to the ground via the switch SW, and the outer conductor layer (24) is connected to the ground. 9. A signal line extending from an input terminal (42) to an output terminal (43) includes a first inductance element L1, a second inductance element L2 and a third inductance element L3, and is connected to the first inductance element L1. The first dielectric resonance device is directly connected to the connection point between the second inductance elements L2.
The dielectric filter according to claim 8, wherein (13) is connected, and the second dielectric resonance device (14) is directly connected to a connection point between the second inductance element L2 and the third inductance element L3. 10. The signal line extending from the input terminal (42) to the output terminal (43) has a first capacitance element C4, a second capacitance element C5 and a third capacitance element C6.
And the first dielectric resonance device (11) at the connection point between the first capacitance element C4 and the second capacitance element C5.
Are connected to each other, and the second dielectric resonator (1) is connected to a connection point between the second capacitance element C5 and the third capacitance element C6.
The dielectric filter according to claim 6, wherein 2) is connected. 11. A main filter circuit (82) having a pass band in a frequency band of a high frequency signal to be received or transmitted.
And a trap circuit (83) for attenuating a signal component in a frequency band deviated from the pass band, the trap circuit (83) comprising a coaxial dielectric resonator (2). The coaxial dielectric resonator (2) includes a dielectric block (21) having a through hole (22) and an outer conductor layer (24) formed on the outer peripheral surface of the dielectric block (21).
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other and the outer conductor layer (24) on the outer peripheral surface of the dielectric block (21). And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. A dielectric filter for changing the signal attenuation characteristic of the trap circuit (83) by connecting or disconnecting the capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) with respect to the capacitance C. 12. A reception filter device (5) comprising a reception filter device (5) and a transmission filter device (6) connected in parallel to an antenna terminal (71) to which an antenna (7) is to be connected. ) And the transmission filter device (6) each include one or a plurality of coaxial dielectric resonators (2), and the coaxial dielectric resonator (2) is a dielectric block () having a through hole (22). 21) and the outer conductor layer (24) formed on the outer peripheral surface of the dielectric block (21).
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other and the outer conductor layer (24) on the outer peripheral surface of the dielectric block (21). And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of each coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching of each switch SW. The capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) is connected to or disconnected from the capacitance C, so that the signals of the reception filter device (5) and the transmission filter device (6) are connected. Dielectric duplexer that changes passage characteristics. 13. A reception filter device (54) comprising a reception filter device (54) and a transmission filter device (64) connected in parallel to an antenna terminal (71) to which an antenna (7) is to be connected. ) Is configured by connecting in series a main filter circuit (82) having a pass band in the frequency band of the received signal and a trap circuit (83) for attenuating the frequency band of the transmitted signal, and the trap circuit ( 83) is a coaxial dielectric resonator
The coaxial dielectric resonator (2) comprises a dielectric block (21) having a through hole (22) and an outer conductor layer formed on the outer peripheral surface of the dielectric block (21). (twenty four)
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other and the outer conductor layer (24) on the outer peripheral surface of the dielectric block (21). And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. A dielectric for connecting or disconnecting the capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) with respect to the capacitance C, thereby changing the signal passing characteristic of the reception filter device (54). Duplexer. 14. The transmission filter device (64) comprises a main filter circuit (84) having a pass band in the frequency band of the transmission signal and an attenuation band in the frequency band of the reception signal, the main filter circuit (84). Comprises a coaxial dielectric resonator (2). The coaxial dielectric resonator (2) comprises a dielectric block (21) having a through hole (22) and an outer peripheral surface of the dielectric block (21). Outer Conductor Layer Formed (24)
And an inner conductor layer (23) formed on the inner peripheral surface of the through hole (22) of the dielectric block (21) and one end surface where the through hole (22) of the dielectric block (21) opens. The outer conductor layer (24) is electrically connected to the short-circuit conductor layer (25) that is formed and short-circuits the outer conductor layer (24) and the inner conductor layer (23) to each other and the outer conductor layer (24) on the outer peripheral surface of the dielectric block (21). And a separated conductor layer (3) formed separately,
A switch SW is connected to the separation conductor layer (3) of the coaxial dielectric resonator (2), and is formed between the outer conductor layer (24) and the inner conductor layer (23) by switching the switch SW. The capacitance C'formed between the separation conductor layer (3) and the inner conductor layer (23) is connected or disconnected from the capacitance C, thereby changing the signal passing characteristic of the transmission filter device (64). 13. The dielectric duplexer according to item 13. 15. The main filter circuit (82) of the reception filter device (54) is constituted by one or a plurality of coaxial dielectric resonators (9), and the coaxial dielectric resonator () constituting the main filter circuit (82). The dielectric according to claim 13 or 14, wherein 9) and the coaxial dielectric resonator (2) forming the trap circuit (83) are integrated by including a common dielectric block (91). Duplexer.