JP2009194571A - Multimode dielectric resonator and method of adjusting the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multimode dielectric resonator capable of easily adjusting desired frequency characteristics without increasing transmission loss by a relatively simple configuration. <P>SOLUTION: The multimode dielectric resonator includes a cylindrical dielectric resonator body 10 which is fixed in a cavity enclosed in a conductor case 11 and includes a side surface plane 10a, and in which a plurality of resonance modes can be excited, and a dielectric adjusting piece 14 which is disposed facing the upper face of the dielectric resonator body 10, and whose distance D to the dielectric resonator body 10 is adjustable. A direction connecting the dielectric adjusting piece 14 from the medial axis of the dielectric resonator body 10 is configured so as to coincide with or orthogonally cross a direction connecting the side surface plane 10a from the medial axis. A support bar 15 changes the position of the dielectric adjusting piece 14 to adjust the distance D so that frequency characteristics can thereby be adjusted appropriately. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a multimode dielectric resonator capable of exciting a plurality of resonance modes corresponding to a plurality of frequencies.

Generally, a resonator filter is incorporated in a base station such as a mobile phone. In order to configure such a resonator filter with a small size and high performance, a multimode resonator capable of responding to a plurality of frequencies by exciting a plurality of resonance modes has attracted attention. As the conventional multimode resonator, various structures such as a structure using a cylinder or a structure using a rectangular parallelepiped as its basic shape have been proposed (see, for example, Patent Documents 1 and 2). In order to excite a plurality of resonance modes in a structure using a rectangular parallelepiped shape, it is necessary to adopt a structure in which a plurality of rectangular parallelepipeds are combined or a structure in which a part of the rectangular parallelepiped is three-dimensionally deleted. In addition, in order to excite a plurality of resonance modes in a structure using a cylindrical shape, it is necessary to employ a structure provided with a screw member, a cylindrical hole or the like for adjusting the characteristics of the resonator body.
JP-A-57-194603 JP-A-61-121502

  Of the above-described multimode resonators, the structure using a rectangular parallelepiped shape needs to have a complicated shape in order to adjust a desired frequency characteristic at the time of manufacturing, leading to an increase in manufacturing cost. On the other hand, in the structure using the cylindrical shape among the above-described multimode resonators, the structure of the resonator body is relatively simple and easy to manufacture. However, if it is assumed that the structure for adjusting the characteristics is provided, there are problems such as an increase in transmission signal loss due to the screw member and complicated processing for forming a cylindrical hole. Furthermore, if the frequency adjustment of the multi-mode resonator is performed using the above-described characteristic adjustment structure, a plurality of frequencies change in a complicated manner depending on the design conditions. It is not easy to realize frequency characteristics.

  Accordingly, the present invention has been made to solve these problems, and a multimode dielectric resonator capable of easily adjusting a desired frequency characteristic without increasing transmission loss with a relatively simple structure. The purpose is to provide.

  In order to solve the above problems, a multimode dielectric resonator according to the present invention is fixed in a cavity surrounded by a conductor, and has a cylindrical dielectric resonance having a side structure for exciting a plurality of resonance modes. A dielectric main body, and a dielectric adjustment piece arranged to face a side surface of the dielectric resonator main body and configured to be capable of adjusting a distance between the dielectric resonator main body and the dielectric resonator main body. The direction connecting the dielectric adjustment piece from the central axis is configured to coincide with or orthogonal to the direction connecting the side surface structure from the central axis.

  According to the multimode dielectric resonator of the present invention, the cylindrical dielectric resonator body excites a plurality of resonance modes by the action of the side surface structure, and the corresponding frequency characteristics are imparted to the transmission signal. And when adjusting the distance between the dielectric resonator body by displacing the dielectric adjustment piece on the side, depending on the positional relationship between the side structure and the dielectric adjustment piece, it acts on one of the resonance modes and is desired The resonant frequency can be selectively adjusted. Therefore, it is possible to realize a multimode dielectric resonator that can easily adjust the frequency characteristics with a simple structure without requiring a special structure or complicated processing for adjusting the frequency characteristics.

  In the present invention, the dielectric resonator main body is attached to the conductor on the side surface side and includes a circular cross section of the dielectric resonator main body in a first direction and the first direction from the central axis. A pair of input / output terminals respectively provided in a second direction orthogonal to each other is provided, and the direction connecting the dielectric adjustment piece from the central axis is approximately 45 with respect to each of the first direction and the second direction. You may comprise so that a degree may be made.

  In the present invention, the side surface structure may be a structure in which a part of the side surface of the dielectric resonator body is cut. In this case, within the plane including the circular cross section of the dielectric resonator body, the normal direction of the cutting surface of the side structure is approximately 45 degrees with respect to each of the first direction and the second direction. You may comprise so that an angle may be made.

  In order to solve the above problems, a multimode dielectric resonator according to the present invention is fixed in a cavity surrounded by a conductor and has a cylindrical dielectric structure having a side structure for exciting a plurality of resonance modes. A body resonator body, a first dielectric adjustment piece arranged to face a side surface of the dielectric resonator body, and configured to be capable of adjusting a first distance between the body and the dielectric resonator body; A dielectric resonator main body, and a second dielectric adjustment piece arranged to face a side surface of the dielectric resonator main body and configured to be capable of adjusting a second distance between the dielectric resonator main body and the dielectric resonator main body. The direction connecting the first dielectric adjustment piece from the central axis is perpendicular to the direction connecting the side structure from the central axis, and the second dielectric adjustment piece is connected from the central axis of the dielectric resonator body. The connecting direction coincides with the direction connecting the side structures from the central axis, and the front A direction connecting said first dielectric adjusting pieces from the central axis, the direction connecting the second dielectric adjusting pieces from the center axis is configured to be orthogonal to each other.

  In the present invention, there is further provided a third dielectric adjustment piece that is arranged to be opposed to the upper surface or the bottom surface of the dielectric resonator body and is configured to be capable of adjusting a third distance from the dielectric resonator body. May be.

  In the present invention, there is further provided a third dielectric adjustment piece that is disposed to face a side surface of the dielectric resonator body and is configured to be capable of adjusting a third distance between the dielectric resonator body, The direction connecting the third dielectric adjustment piece from the central axis is the direction connecting the first dielectric adjustment piece from the central axis and the direction connecting the second dielectric adjustment piece from the central axis, respectively. However, it may be configured to form approximately 45 degrees.

  On the other hand, in order to solve the above-described problem, the adjustment method of the multimode dielectric resonator according to the present invention includes the dielectric that excites the first resonance mode and the resonance mode having a second frequency higher than the first frequency. For the body resonator body, one of the first frequency and the second frequency is independently adjusted by the first dielectric adjustment piece, and the other frequency characteristic is adjusted to the second dielectric. It is adjusted independently by the body adjustment piece.

  Also, the adjustment method of the multimode dielectric resonator of the present invention is such that the dielectric resonator main body that excites the resonance mode of the first frequency and the second frequency higher than the first frequency, respectively, The first dielectric adjustment piece, the second dielectric adjustment piece, and the third dielectric adjustment piece are independently adjusted, and the first frequency and the second frequency are respectively set to desired values. The frequency characteristics are adjusted.

  As described above, according to the present invention, the dielectric resonator main body has a side surface structure for exciting a plurality of resonance modes, and a multimode dielectric using a dielectric adjustment piece disposed opposite to the side surface. Since the resonator is configured, a desired resonance frequency corresponding to a specific resonance mode can be selectively adjusted by adjusting the distance between the dielectric adjustment piece and the dielectric resonator main body. In this case, when adjusting a plurality of resonance frequencies corresponding to a plurality of resonance modes, if each of the dielectric adjustment pieces corresponding to each resonance mode is provided and adjusted independently, each resonance frequency can be adjusted efficiently. As described above, by using the dielectric resonator according to the present invention, a complex mode for frequency adjustment is not required, transmission loss is small, and high-accuracy frequency characteristics can be easily realized and applied to various filters. A dielectric resonator can be realized.

  Embodiments of the present invention will be described with reference to the drawings. In the following, four different embodiments will be described when the present invention is applied to a dielectric resonator having two peaks in frequency characteristics corresponding to two resonance modes (double mode).

(First embodiment)
The structure and characteristics of the dielectric resonator according to the first embodiment will be described. Regarding the dielectric resonator of the first embodiment, FIG. 1 shows a side sectional view and FIG. 2 shows a top view. As shown in FIGS. 1 and 2, the dielectric resonator according to the first embodiment includes a dielectric resonator main body 10, a conductor case 11, a support base 12, a pair of input / output terminals 13, and a dielectric adjustment. A piece 14 and a support bar 15 are provided.

  The dielectric resonator body 10 has a shape in which a part of a column is cut, and is disposed at a substantially central portion in a cavity surrounded by a cylindrical conductor case 11. The bottom surface of the dielectric resonator body 10 is fixed by a support base 12 attached to a conductor case 11. The dielectric resonator body 10 is formed using a dielectric material having a predetermined dielectric constant. The dielectric resonator main body 10 and the external space are in a state of being electrically cut off by the surrounding conductor case 11. The support base 12 is made of alumina, for example, and has a cylindrical shape.

  As shown in FIG. 2, the pair of input / output terminals 13 are respectively attached to the side surfaces of the conductor case 11. Among the pair of input / output terminals 13, one input / output terminal 13 is supplied with an input signal supplied from the outside, and the other input / output terminal 13 outputs an output signal excited in a plurality of resonance modes to the outside. Is done. The pair of input / output terminals 13 can be used with their input / outputs interchanged. Although the X axis and the Y axis are shown in the lower part of FIG. 2 for the sake of convenience, when viewed from the central axis of the dielectric resonator body 10, the position of one input / output terminal 13 is arranged in the X direction and the other input / output The position of the terminal 13 is arranged in the Y direction. That is, the pair of input / output terminals 13 are in a positional relationship orthogonal to each other within a plane including the circular cross section of the dielectric resonator body 10.

  The cut surface 10a of the dielectric resonator body 10 is formed such that the normal line forms an angle of 45 degrees with respect to the X axis and the Y axis in the horizontal plane. Forming the cutting surface 10a at such an angle is an example of a side structure for the dielectric resonator body 10 to excite two resonance modes. The cutting amount H of the cutting surface 10a shown in FIG. 1, that is, the distance from the outer peripheral position of the circular cross section of the dielectric resonator body 10 before cutting to the center position of the cutting surface 10a greatly affects the resonance mode characteristics. It is desirable to determine an optimum cutting amount H that provides desired characteristics.

  The dielectric adjustment piece 14 is disposed on the side surface of the dielectric resonator body 10 and is formed in a cylindrical shape having a central axis orthogonal to the central axis of the dielectric resonator main body 10. As shown in FIG. 2, the dielectric adjustment piece 14 forms an angle of 45 degrees with respect to each of the X axis and the Y axis when viewed from the central axis of the dielectric resonator body 10 and is normal to the cutting surface 10 a. And 90 degrees. A support rod 15 is attached to one end of the dielectric adjustment piece 14, and the distance D between the dielectric adjustment piece 14 and the dielectric resonator body 10 can be freely adjusted by changing the distance with the support rod 15. The dielectric adjustment piece 14 is formed using the same dielectric material as that of the dielectric resonator body 10.

  In the configuration of the first embodiment, due to the positional relationship between the pair of input / output terminals 13 and the cutting surface 10a, the electric fields based on the two resonance modes are generated in two directions that form 45 degrees with respect to the X axis and the Y axis. . On the other hand, since the dielectric adjustment piece 14 is arranged in the electric field direction of one resonance mode, adjusting the distance D changes the two resonance frequencies corresponding to the two resonance modes differently. Details of such adjustment of the resonance frequency will be described later.

  The characteristics of the dielectric resonator according to the first embodiment will be described with reference to FIGS. Here, as an example of the sizes of the dielectric resonator body 10 and the dielectric adjustment piece 14, for example, the dielectric resonator body 10 has a diameter of about 37 mm and a height of about 10 mm. The diameter is set to about 10 mm and the height is set to about 7.5 mm. Further, the adjustment range of the dielectric adjustment piece 14 is assumed to be a range in which the distance D between the dielectric resonator body 10 and the dielectric resonator body 10 is 2 to 6 mm.

  FIG. 3 shows transmission characteristics in the dielectric resonator. The graph shows the insertion loss (S parameter S21) of a signal transmitted from one input / output terminal 13 to the other input / output terminal 13 in a relatively narrow frequency range near 2 GHz. In FIG. 3, the above-mentioned distance D is changed to four ways (D = 3, 4, 5, 6 mm), and the respective transmission characteristics are compared and shown. As can be seen from FIG. 3, the insertion loss has a peak close to 0 (dB) on the low frequency side and the high frequency side, respectively, and the insertion loss increases at other frequencies.

  The two peaks in the graph of FIG. 3 appear at two resonance frequencies corresponding to the two resonance modes of the dielectric resonator. Hereinafter, the resonance frequency on the low frequency side is expressed as FL, and the resonance frequency on the high frequency side is expressed as FH. As shown in FIG. 3, the resonance frequency FL on the low frequency side is substantially constant even if the distance D of the dielectric adjustment piece 14 changes, whereas the resonance frequency FH on the high frequency side is from a distance D of 3 mm. It increases as it becomes longer to 6 mm.

  FIG. 4 shows the relationship between the change in the distance D and the frequency. As shown in FIG. 4, in addition to the two resonance frequencies FL and FH, the change of the average frequency FA (FA = (FL + FH) / 2) with respect to the distance D is shown in a graph. Reflecting the transmission characteristics of FIG. 3, as the distance D increases, the resonance frequency FL on the low frequency side changes substantially constant, the resonance frequency FH on the high frequency side increases, and the average frequency FA increases gently. I understand. As described above, the dielectric adjustment piece 14 in the first embodiment has a role of adjusting the resonance frequency FH on the high frequency side. As described above, this is based on the fact that the displacement of the dielectric adjustment piece 14 acts only on the high-frequency side resonance frequency FH for the two resonance modes.

  FIG. 5 shows the relationship between the change in the distance D and the above-described average frequency FA and coupling coefficient k. Here, the coupling coefficient k is an amount that is obtained by k = (FH−FL) / FA and represents the degree to which the two resonance frequencies FL and FH are relatively separated. Note that the frequency axis in FIG. 5 is represented by a scale in a narrower range than that in FIG. 4 in order to enlarge and show the change in the average frequency FA. It can be seen that as the distance D increases, the average frequency FA increases, and the coupling coefficient k increases accordingly. In this case, the average frequency FA and the coupling coefficient k change more rapidly as the distance D is smaller.

  3 to 5 show examples of characteristics obtained by using the dielectric resonator according to the first embodiment. In practice, various characteristics can be realized according to design conditions. it can. For example, the characteristics shown in FIGS. 3 to 5 can be changed by changing the cutting amount H (FIG. 1) with respect to the dielectric resonator body 10. Further, the size of each of the dielectric resonator body 10 and the dielectric adjustment piece 14 has a great influence on the frequency characteristics. As described above, it is desirable to optimally set the design conditions of the dielectric resonator so that desired characteristics can be obtained in the circuit incorporating the dielectric resonator of the first embodiment.

(Second Embodiment)
Next, the structure and characteristics of the dielectric resonator according to the second embodiment will be described. FIG. 6 is a top view of the dielectric resonator according to the second embodiment. The side cross-sectional view of the dielectric resonator according to the second embodiment can be expressed in the same manner as in FIG. As shown in FIG. 6, the dielectric resonator according to the second embodiment is similar to the first embodiment in that the dielectric resonator main body 10, the conductor case 11, the support base 12, and the pair of input / output terminals 13. The dielectric adjustment piece 14 and the support bar 15 are provided. In this configuration, the difference from the first embodiment is the arrangement of the dielectric adjustment piece 14, and the other points are the same, and the description thereof is omitted.

  The dielectric adjustment piece 14 of the second embodiment is at a 45 ° angle with respect to each of the X axis and the Y axis when viewed from the central axis of the dielectric resonator body 10 and is opposed to the cutting surface 10a ( (On the normal line of the cutting surface 10a). Compared to FIG. 1, the dielectric adjustment piece 14 of FIG. 6 is different in position by 90 degrees and is disposed close to one input / output terminal 13 side of the pair of input / output terminals 13. Also in this case, the distance D between the dielectric adjustment piece 14 and the dielectric resonator body 10 can be freely adjusted by changing the distance by the support rod 15. In the configuration of the second embodiment, an action different from that of the first embodiment is generated for the electric field based on the two resonance modes, and the two resonance frequencies are different from those of the first embodiment by adjusting the distance D. Make different changes.

  The characteristics of the dielectric resonator according to the second embodiment will be described with reference to FIGS. Here, it is assumed that the sizes of the dielectric resonator body 10 and the dielectric adjustment piece 14 are set in the same manner as in the first embodiment. Moreover, about the adjustment range of the dielectric material adjustment piece 14, the range whose distance D is 3-6 mm is assumed.

  FIG. 7 shows transmission characteristics in the dielectric resonator. As in the case of FIG. 3, the insertion loss (S parameter S21) in a relatively narrow frequency range near 2 GHz is shown in a graph, and the above-mentioned distance D is changed to four ways (D = 3, 4, 5, 6 mm). The respective transmission characteristics are shown in comparison. The two peaks in the graph of FIG. 7 correspond to the resonance frequency FL on the low frequency side and the resonance frequency FH on the high frequency side, as in FIG. In FIG. 7, contrary to FIG. 3, the resonance frequency FL on the low frequency side increases as the distance D increases from 3 mm to 6 mm, whereas the resonance frequency FH on the high frequency side increases with the dielectric adjusting piece 14. Even if the distance D changes, it is substantially constant.

  FIG. 8 shows the relationship between the change in the distance D and the frequency. As shown in FIG. 8, in addition to the two resonance frequencies FL and FH, the change with respect to the distance D of the average frequency FA is shown by a graph similarly to the first embodiment. Reflecting the transmission characteristics of FIG. 7, as the distance D increases, the resonance frequency FL on the low frequency side increases, the resonance frequency FH on the high frequency side changes substantially constant, and the average frequency FA increases gently. I understand. As described above, the dielectric adjustment piece 14 in the second embodiment has a role of adjusting the resonance frequency FL on the low frequency side. As described above, this is based on the fact that the displacement of the dielectric adjustment piece 14 acts only on the resonance frequency FL on the low frequency side for the two resonance modes.

  FIG. 9 shows the relationship between the change in the distance D and the above-described average frequency FA and coupling coefficient k. Note that the frequency axis in FIG. 9 is represented by a scale in a narrower range than that in FIG. 8 in order to enlarge and show the change in the average frequency FA. It can be seen that as the distance D increases, the average frequency FA increases, and the coupling coefficient k decreases in conjunction with this. In this case, the average frequency FA and the coupling coefficient k change more rapidly as the distance D is smaller. Compared with FIG. 5 of the first embodiment, the direction of change of the coupling coefficient k is opposite, but this is because the difference from the resonance frequency FH on the high frequency side is relatively reduced due to the increase of the resonance frequency FL on the low frequency side. It is to do.

  As described above, in the dielectric resonator according to the first and second embodiments, the direction of the cutting surface 10a and the direction of the dielectric adjustment piece 14 are orthogonal to each other when viewed from the central axis of the dielectric resonator body 10 ( Since they are arranged so as to match (FIG. 2) or match (FIG. 6), it is possible to selectively act on one of the two resonance modes. Therefore, by adjusting the distance D of the dielectric adjustment piece 14, only one of the two resonance frequencies FL and FH corresponding to the two resonance modes can be selectively adjusted. In the first and second embodiments, a structure in which one dielectric adjustment piece 14 is provided is shown. However, the dielectric adjustment piece 14 includes both the dielectric adjustment piece 14 in FIG. 2 and the dielectric adjustment piece 14 in FIG. A body resonator may be configured. In this case, by independently adjusting the distance D of each dielectric adjustment piece 14, the two resonance frequencies FL and FH corresponding to the two resonance modes can be individually adjusted to easily obtain a desired frequency characteristic. It becomes feasible. Since the resonance frequencies FL and FH can be set finely with respect to the change in the distance D, it is suitable for application to a band-variable filter capable of highly accurate frequency adjustment, for example.

(Third embodiment)
Next, the structure and characteristics of the dielectric resonator according to the third embodiment will be described. As for the dielectric resonator according to the third embodiment, FIG. 10 shows a side sectional view and FIG. 11 shows a top view. As shown in FIGS. 10 and 11, in the dielectric resonator according to the third embodiment, the dielectric resonator main body 10, the conductor case 11, the support base 12, and the pair of input / output terminals 13 are the first. And it is comprised similarly to 2nd Embodiment. In addition to these, three dielectric adjustment pieces 14a, 14b, 16 and three support rods 15a, 15b, 17 are provided. Further, the cutting surface 10a formed on the dielectric resonator body 10 is disposed at a position sandwiched between the pair of input / output terminals 13 with the normal direction being 90 degrees different from those in FIGS.

  As shown in FIG. 11, the two dielectric adjustment pieces 14a and 14b correspond to the dielectric adjustment pieces 14 of the first and second embodiments, and have an angle of 45 degrees with respect to each of the X axis and the Y axis. None, and the dielectric adjusting pieces 14a and 14b are arranged so that the directions thereof form 90 degrees. One dielectric adjustment piece 14a is disposed at a position that is 90 degrees with the normal line of the cutting surface 10a, and the other dielectric adjustment piece 14b is located at a position facing the cutting surface 10a (on the normal line of the cutting surface 10a). ). The dielectric adjustment pieces 14a and 14b can be freely adjusted by changing the distances D1 and D2 between the dielectric resonator body 10 and the support rods 15a and 15b, respectively. Thereby, the dielectric adjustment pieces 14a and 14b act on two electric fields based on the two resonance modes, respectively, and the two resonance frequencies corresponding to the two resonance modes can be adjusted independently.

  On the other hand, as shown in FIGS. 10 and 11, the dielectric adjustment piece 16 is disposed to face the upper surface of the dielectric resonator body 10. The shape of the dielectric adjustment piece 16 is a cylindrical shape whose center axis coincides with that of the dielectric resonator main body 10, and the diameter of the circular cross section is set smaller than that of the dielectric resonator main body 10. A support rod 17 is attached to the upper portion of the dielectric adjustment piece 16, and the distance D 3 (FIG. 10) between the dielectric resonator body 10 and the dielectric adjustment piece 16 can be changed by the support rod 17. In this case, unlike the above-described dielectric adjustment pieces 14a and 14b, the dielectric adjustment piece 16 has a symmetrical positional relationship in the horizontal plane, so that the vertical displacement thereof is two corresponding to the two resonance modes. It has almost the same effect on the electric field. As a result, as described later, the two frequencies corresponding to the two resonance modes change in conjunction with each other.

  The characteristics of the dielectric resonator according to the third embodiment will be described with reference to FIGS. FIG. 12 assumes a case where the distances D1, D2, and D3 of the three dielectric adjustment pieces 14a, 14b, and 16 are independently adjusted with respect to the dielectric resonator of the third embodiment. Measurement results corresponding to A2, A3, and A4 are shown. First, under the reference condition A1, the distances D1 and D2 are both adjusted to 12.5 mm and the distance D3 is adjusted to 7.5 mm. For this condition A1, a condition A2 in which only the distance D3 is changed to 2.5 mm, a condition A3 in which only the distance D1 is changed to 2.5 mm, and a condition A4 in which only the distance D2 is changed to 2.5 mm are shown. Has been. And about each conditions A1-A4, the measurement result of the above-mentioned average frequency FA and the coupling coefficient k is shown collectively.

  FIG. 13 shows transmission characteristics corresponding to the conditions A1 to A4 in FIG. The graph of FIG. 13 shows the frequency characteristics of the insertion loss having two peaks as in FIGS. 3 and 7, but there is a difference in the tendency of each graph regarding the conditions A1 to A4. That is, when the condition A1 is used as a reference, in the case of the condition A2, the two resonance frequencies FL and FH change in conjunction with each other while the coupling coefficient k is maintained. This is a characteristic based on the action of the dielectric adjusting piece 16 described above, and as shown in FIG. 12, substantially the same coupling coefficient k is obtained for the conditions A1 and A2.

  On the other hand, in the case of condition A3, the resonance frequency FL on the low frequency side does not change, and the resonance frequency FH on the high frequency side decreases. On the other hand, in the case of condition A4, the resonance frequency FL on the low frequency side decreases, and the resonance frequency FH on the high frequency side does not change. These characteristics reflect adjustments based on the first and second embodiments, respectively. As described above, one or both of the resonance frequencies FL and FH, or the coupling coefficient k can be selectively adjusted by the three dielectric adjustment pieces 14a, 14b, and 16, respectively.

  FIG. 14 assumes a case where the distances D1, D2, and D3 of the three dielectric adjustment pieces 14a, 14b, and 16 are adjusted in combination with the dielectric resonator of the third embodiment, and three conditions A1, The measurement results corresponding to A5 and A6 are shown. First, the reference condition A1 is the same as in FIG. For this condition A1, there are shown a condition A5 in which both the distances D1 and D2 are changed to 2.5 mm, and a condition A6 in which all the distances D1, D2, and D3 are changed to 2.5 mm. And the measurement result of the above-mentioned average frequency FA and the coupling coefficient k is shown collectively about each conditions A1, A5, and A6.

  FIG. 15 shows transmission characteristics corresponding to the conditions A1, A5, and A6 in FIG. The graph of FIG. 15 shows the frequency characteristics of insertion loss having two peaks, as in FIG. On the basis of the condition A1, in the case of the condition A5, both the two resonance frequencies FL and FH are greatly reduced. In this case, the coupling coefficient k is slightly increased. On the other hand, in the case of condition A6, the two resonance frequencies FL and FH are much lower than in condition A5. In this case, the coupling coefficient k is substantially the same in the conditions A5 and A6.

(Fourth embodiment)
Next, the structure and characteristics of the dielectric resonator according to the fourth embodiment will be described. FIG. 16 shows a top view of the dielectric resonator of the fourth embodiment. As shown in FIG. 16, in the dielectric resonator according to the fourth embodiment, the dielectric resonator body 10, the conductor case 11, the support base 12, the pair of input / output terminals 13, and the dielectric adjustment piece 14a. , 14b and the support rods 15a, 15b are configured similarly to the third embodiment. On the other hand, the dielectric adjustment piece 16 and the support bar 17 of the third embodiment are not provided, and instead, the dielectric adjustment piece 18 and the support bar 19 are provided. Below, description is abbreviate | omitted about the component which is common in 3rd Embodiment. Further, regarding the sectional side view of the dielectric resonator according to the fourth embodiment, the sectional view of the dielectric adjusting piece 18 and the support rod 19 may be added to the sectional side view of FIG.

  The dielectric adjustment piece 18 is positioned in the X-axis direction when viewed from the central axis of the dielectric resonator body 10 and is disposed at an angle of 45 degrees with respect to each of the two dielectric adjustment pieces 14a and 14b. . The dielectric adjustment piece 18 can be freely adjusted by changing the distance D4 between the dielectric resonator main body 10 and the dielectric resonator body 10 by the support rod 19. This dielectric adjustment piece 18 can act equally on two electric fields based on two resonance modes.

  Characteristics of the dielectric resonator according to the fourth embodiment will be described with reference to FIGS. 17 and 18. FIG. 17 assumes that the distance D4 of the distances D1, D2, and D4 of the three dielectric adjustment pieces 14a, 14b, and 18 is adjusted with respect to the dielectric resonator of the fourth embodiment. The measurement results corresponding to the conditions B1 and B2 are shown. First, in the reference condition B1, the distances D1 and D2 are both adjusted to 2.5 mm, and the distance D4 is adjusted to 12.5 mm. For this condition B1, a condition B2 in which only the distance D4 is changed to 2.5 mm is shown. And about the conditions B1 and B2, the measurement result of the above-mentioned average frequency FA and the coupling coefficient k is shown collectively.

  FIG. 18 shows transmission characteristics corresponding to the conditions B1 and B2 in FIG. The graph of FIG. 18 shows the frequency characteristics of the insertion loss having two peaks, as in FIG. 13 and FIG. When the condition B1 is used as a reference, in the case of the condition B2, the two resonance frequencies FL and FH are both lowered. In this case, the coupling coefficient k is slightly reduced, but remains sufficiently small. Accordingly, the two resonance frequencies FL and FH can be adjusted in conjunction with the dielectric adjustment piece 18.

  As described above, the dielectric resonators of the third and fourth embodiments include the second dielectric adjustment pieces 14a and 14b included in the dielectric resonators of the first and second embodiments, respectively. Since the third dielectric adjustment piece 16 or 18 is added, various adjustment methods of frequency characteristics can be realized. That is, in the dielectric resonator, a desired parameter among the two resonance frequencies FL and FH, the average frequency FA, and the coupling coefficient k can be freely adjusted, and application to various filters becomes possible.

  As mentioned above, although the content of this invention was concretely demonstrated based on 1st-4th embodiment, this invention is not limited to the above-mentioned embodiment, In the range which does not deviate from the summary, various changes are carried out. Can be applied. For example, in the present embodiment, the case where the dielectric adjustment piece 14 is formed in a columnar shape has been described. However, the dielectric adjustment piece 14 can be formed in a different shape without being limited to the columnar shape. For example, the dielectric adjustment piece 14 may be formed in a shape whose cross section is a combination of polygons. Furthermore, in the present embodiment, the dielectric adjustment piece 14 is not limited to being formed using the same dielectric material as that of the dielectric resonator body 10, and a dielectric having a relative dielectric constant different from that of the dielectric resonator body 10. The dielectric adjustment piece 14 may be formed using a material.

  On the other hand, in this embodiment, although the case where the dielectric resonator main body 10 was cut by the cutting surface 10a shown in FIG. 1 etc. was demonstrated, it is not limited to this cutting method. The arrangement and cutting method of the cutting surface 10a of the dielectric resonator body 10 can be freely changed within a range in which the effects of the present invention can be obtained. In this case, in this embodiment, the structure in which the dielectric resonator main body 10 excites two resonance modes is shown. However, the frequency characteristics having a plurality of peaks are obtained by exciting more resonance modes by devising the cutting method. May be realized.

It is a sectional side view of the dielectric resonator of 1st Embodiment. It is a top view of the dielectric resonator of the first embodiment. It is a figure which shows the transmission characteristic in the dielectric resonator of 1st Embodiment. It is a figure which shows the relationship between the change of the distance D and the frequency in the dielectric resonator of 1st Embodiment. It is a figure which shows the relationship of the change of the distance D, the average frequency FA, and the coupling coefficient k in the dielectric resonator of 1st Embodiment. It is a top view of the dielectric resonator of 2nd Embodiment. It is a figure which shows the transmission characteristic in the dielectric resonator of 2nd Embodiment. It is a figure which shows the change of the distance D and the relationship of a frequency in the dielectric resonator of 2nd Embodiment. It is a figure which shows the relationship of the change of the distance D, the average frequency FA, and the coupling coefficient k in the dielectric resonator of 2nd Embodiment. It is a sectional side view of the dielectric resonator of 3rd Embodiment. It is a top view of the dielectric resonator of 3rd Embodiment. It is a figure which shows the conditions and measurement result in the case of adjusting each distance D1, D2, D3 independently with respect to the dielectric resonator of 3rd Embodiment. It is a figure which shows the transmission characteristic corresponding to each condition of FIG. It is a figure which shows the conditions and measurement result in the case of adjusting combining each distance D1, D2, and D3 with respect to the dielectric resonator of 3rd Embodiment. It is a figure which shows the transmission characteristic corresponding to each condition of FIG. It is a top view of the dielectric resonator of 4th Embodiment. It is a figure which shows the conditions and measurement result in the case of adjusting the distance D4 with respect to the dielectric resonator of 4th Embodiment. It is a figure which shows the transmission characteristic corresponding to each condition of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Dielectric resonator main body 10a ... Cutting surface 11 ... Conductor case 12 ... Support stand 13 ... Input / output terminal 14, 14a, 14b, 16, 18 ... Dielectric adjustment piece 15, 15a, 15b, 17, 19 ... Support rod

Claims (9)

A cylindrical dielectric resonator body fixed in a cavity surrounded by conductors and having a side structure for exciting a plurality of resonance modes;
A dielectric adjustment piece arranged to face the side surface of the dielectric resonator body and configured to be able to adjust the distance between the dielectric resonator body; and
The multimode dielectric resonator is characterized in that a direction connecting the dielectric adjustment piece from the central axis of the dielectric resonator body coincides with or is orthogonal to a direction connecting the side surface structure from the central axis. A second direction that is attached to the conductor on the side surface side of the dielectric resonator body and that is orthogonal to the first direction and the first direction from the central axis within a plane including a circular cross section of the dielectric resonator body. A pair of input / output terminals respectively located in the direction of
2. The multimode dielectric resonance according to claim 1, wherein a direction connecting the dielectric adjustment piece from the central axis is approximately 45 degrees with respect to each of the first direction and the second direction. vessel.   The multi-mode dielectric resonator according to claim 2, wherein the side surface structure is a structure obtained by cutting a part of a side surface of the dielectric resonator body.   In the plane including the circular cross section of the dielectric resonator body, the normal direction of the cutting surface of the side structure forms an angle of approximately 45 degrees with respect to each of the first direction and the second direction. The multimode dielectric resonator according to claim 3. A cylindrical dielectric resonator body fixed in a cavity surrounded by conductors and having a side structure for exciting a plurality of resonance modes;
A first dielectric adjustment piece disposed opposite to the side surface of the dielectric resonator body and configured to be capable of adjusting a first distance between the dielectric resonator body; and
A second dielectric adjustment piece disposed opposite to the side surface of the dielectric resonator main body and configured to be capable of adjusting a second distance between the dielectric resonator main body,
The direction connecting the first dielectric adjustment piece from the central axis of the dielectric resonator body is perpendicular to the direction connecting the side structure from the central axis, and from the central axis of the dielectric resonator body The direction connecting the second dielectric adjustment pieces coincides with the direction connecting the side structures from the central axis,
The multi-mode dielectric resonator according to claim 1, wherein a direction connecting the first dielectric adjustment piece from the central axis and a direction connecting the second dielectric adjustment piece from the central axis are orthogonal to each other.   And further comprising a third dielectric adjustment piece that is arranged to face the upper surface or the bottom surface of the dielectric resonator main body and is configured to be capable of adjusting a third distance between the dielectric resonator main body and the dielectric resonator main body. The multimode dielectric resonator according to claim 5. A third dielectric adjustment piece disposed opposite to the side surface of the dielectric resonator body and configured to adjust a third distance between the dielectric resonator body and the dielectric resonator body;
The direction connecting the third dielectric adjustment piece from the central axis is the direction connecting the first dielectric adjustment piece from the central axis and the direction connecting the second dielectric adjustment piece from the central axis. 6. The multimode dielectric resonator according to claim 5, wherein the multimode dielectric resonator is approximately 45 degrees with respect to each other. A method for adjusting a multimode dielectric resonator according to claim 5, comprising:
One frequency of the first frequency and the second frequency for the dielectric resonator body that excites the resonance mode of the first frequency and the second frequency higher than the first frequency, respectively. An adjustment method, wherein the characteristic is adjusted independently by the first dielectric adjustment piece, and the other frequency characteristic is adjusted independently by the second dielectric adjustment piece. A method for adjusting a multimode dielectric resonator according to claim 6 or 7, comprising:
For the dielectric resonator main body that excites the resonance mode of the first frequency and the second frequency higher than the first frequency, the first dielectric adjustment piece and the second dielectric adjustment An adjustment method comprising adjusting a piece and the third dielectric adjustment piece independently to adjust each of the first frequency and the second frequency to a desired frequency characteristic.

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