CN116259942A - Ceramic waveguide duplexer - Google Patents

Abstract

The invention provides a ceramic waveguide duplexer, comprising a plurality of resonant cavities defined by a plurality of partitions formed by penetrating through one surface and the other surface of a single ceramic block according to a preset pattern; a common interface formed as a hole structure penetrating the ceramic block in a region of a common resonator for inputting/outputting signals to/from the common antenna among the plurality of resonators, and formed as a stepped hole structure having a hole diameter on the other surface side of the ceramic block smaller than the hole diameter on the one surface side; and a metal layer formed on the outer surface of the ceramic block, wherein the metal layer is formed by removing the ring shape from the step area parallel to the surface of the ceramic block in the common interface of the step hole structure, thereby the broadband signal required by the duplexer can be input and output, and the damage risk can be reduced.

Description

Ceramic waveguide duplexer

Technical Field

The present invention relates to a ceramic waveguide duplexer, and more particularly to a ceramic waveguide duplexer having an input/output port sharing a hole resonator structure.

Background

As communication services develop, data transmission speed increases, and for this reason, the system frequency band also needs to increase, and it is necessary to increase reception sensitivity and minimize Interference (Interference) caused by carriers (carriers) of other communication systems. For this reason, there are increasing demands for low loss (Low insertion loss), high rejection (High rejection), and filters. Coaxial (Coaxial) resonators manufactured from metal materials have advantages in terms of loss, size, and price over other resonators such as dielectric resonators, and are therefore mainly used for implementation of filters for mobile communication systems.

However, due to low output and miniaturization of base station systems such as large (Massive) MIMO antennas, there is a limit in size even when conventional coaxial resonators are used, and there is a need to realize ultra-small filters. For this reason, ceramic waveguide filters are being actively studied as filters that replace filters that utilize existing coaxial resonators. Ceramic waveguide filters are filters that fill cavities with ceramic materials having low losses and high dielectric constants, can be significantly reduced in size compared to existing coaxial resonator filters, and can also provide excellent loss characteristics. In the conventional ceramic waveguide filter, after each ceramic cavity is independently manufactured and a partition wall is formed, a step of bonding each cavity is required. The combination of the cavities is realized by welding, etc.

However, in the cavity bonding process, misalignment tolerance frequently occurs in the bonding process, and thus characteristic change occurs, which causes a problem that the product yield is significantly reduced. In addition, when the characteristic changes due to the machining error, a process of polishing one surface of the ceramic is required, but the ceramic is a very hard material, and thus there is a problem that a high technology is required and fine adjustment is difficult. Furthermore, if Transmission-Zero (Transmission-Zero) for improving attenuation characteristics of a ceramic waveguide filter is to be provided, cross coupling (cross coupling) is mainly used, but there is a problem in that additional work is required in order to achieve cross coupling between cavities that are not adjacent to each other.

In order to solve such a problem, an integrated ceramic waveguide filter has been proposed which includes a plurality of resonant cavities defined by a plurality of penetrating partitions which penetrate between one surface and the other surface of a partition of a single ceramic block in a predetermined pattern to distinguish the partitions of the ceramic block.

Fig. 1 shows an example of a conventional monolithic ceramic waveguide filter, and fig. 2 shows a cross-sectional view of an input/output port of the ceramic waveguide filter of fig. 1.

Fig. 1 is a lower perspective view of the monolithic ceramic waveguide filter, which is realized as a single body as described above with reference to fig. 1, including a plurality of resonant cavities 111 to 116 defined by a plurality of through partition walls 121, 122 formed between one face and the other face of a single ceramic block 100. The plurality of through partition walls 121 and 122 serve to divide the Cavity walls (Cavity walls) of the plurality of resonators 111 to 116, and the space between the plurality of through partition walls formed at intervals among the plurality of through partition walls 121 and 122 forms the joint surface between the plurality of resonators 111 to 116 and serves as a coupling window (coupling window). Also, one surface of the ceramic block 100 for lowering the resonance frequency in each of the plurality of resonance cavities 111 to 116 may form resonance grooves 111 to 116.

As shown in fig. 2, interface grooves 141 and 142 are formed in 2 of the plurality of resonators 111 to 116 of the ceramic waveguide filter as input/output ports for inputting and outputting signals to/from the ceramic waveguide filter. Interface slots 141, 142 may be formed on the other side of the ceramic block 100 in the location of the respective resonant slots 131, 136. In this way, the interface grooves 141, 142 are formed such that the resonance grooves 131, 136 corresponding to the interface grooves 141, 142 transmit signals by capacitive coupling in a case where the resonance grooves 131, 136 corresponding to each other are opposed to each other in the ceramic block 100.

In the ceramic waveguide filter formed as an integral body, the metal layer 160 is formed on the entire outer surface of the single ceramic block 100. The metal layer 160 is formed inside the plurality of through barrier ribs 121 and 122, the plurality of resonance grooves 111 to 116, and the interface grooves 141 and 142. However, as shown in fig. 2, the interface grooves 141, 142 are formed at the periphery thereof with annular grooves 151 as regions where the metal layers 160 are removed, so as to isolate the metal layers 161 formed inside the interface grooves 141, 142 and the external metal layers 160 from each other. That is, the annular groove 151 separates the metal layer 161 formed inside the interface grooves 141, 142 and the metal layer 160 formed outside so as to be isolated from each other. This is to apply an input/output signal to the metal layer 161 formed inside the interface grooves 141 and 142 and to apply a ground voltage to the metal layer 160 formed outside.

Such ceramic waveguide filters were developed and used as Band Pass Filters (BPFs) for a single frequency Band for TDD (Time Division Duplex) large MIMO devices. However, recently there has been a rising demand for FDD (Frequency Division Duplex) or dual frequency TDD applications. Accordingly, there is an increasing demand for an integrated ceramic waveguide duplexer that can be used in place of a filter for TDD to be applied to FDD or dual-frequency TDD.

[ Prior Art literature ]

[ patent literature ]

Korean registered patent No. 10-2241217 (registration day: 2021.04.12)

Disclosure of Invention

Technical problem

The present invention provides an integrated ceramic waveguide duplexer which can be manufactured in a small size by using a common resonator having a hole with a stepped structure capable of inputting and outputting a broadband signal required for the duplexer.

Technical proposal

A ceramic waveguide duplexer according to an embodiment of the present invention for achieving the above object includes: a plurality of resonant cavities defined by a plurality of partitions formed by penetrating through one surface and the other surface of a single ceramic block in a predetermined pattern; a common interface formed in a hole structure penetrating the ceramic block in a region of a common resonator which is used for inputting and outputting signals to and from the common antenna among the plurality of resonators, and in a stepped hole structure having a smaller aperture on the other surface side than on the one surface side of the ceramic block; and a metal layer formed on an outer surface of the ceramic block, and having a ring shape removed from a step region parallel to one surface of the ceramic block in the common interface of the stepped hole structure to form an inner annular groove.

The common interface may be formed in a hole shape of a multi-step structure in which the diameter of the ceramic block is repeatedly reduced stepwise from one surface side.

The width of the inner annular groove is adjustable according to the frequency band of signals input to and output from the common antenna.

The metal layer may be formed with an annular groove removed from the other surface of the ceramic block in the shape of an annular having an inner circle spaced apart from the hole periphery of the common port by a predetermined interval.

The plurality of resonant cavities may be formed in a symmetrical structure to both sides of the ceramic block by the plurality of penetrating partition walls, and the common resonant cavity may be located on a central axis of the ceramic block symmetrical to both sides.

The predetermined transmitting resonant cavity of the plurality of resonant cavities is to be a false transmitting signal which is bandpass filtered to an adjacent resonant cavity in a capacitive coupling mode so as to be transmitted to the common resonant cavity, and the common resonant cavity is to be bandpass filtered to an adjacent resonant cavity in a capacitive coupling mode so as to be capable of being transmitted to the predetermined receiving resonant cavity.

The ceramic waveguide duplexer may further include a transmitting port and a receiving port penetrating the ceramic block in respective regions of the transmitting resonant cavity and the receiving resonant cavity, and having a stepped hole structure having a diameter smaller than that of one side of the ceramic block on the other side thereof, wherein an inner annular groove in which the metal layer is removed in a ring shape is formed in a stepped region parallel to one side of the ceramic block in the stepped hole structure.

The ceramic waveguide duplexer may further include a transmitting interface and a receiving interface, each of which is formed in a groove shape at a position of the transmitting resonant cavity and the receiving resonant cavity in the other surface of the ceramic block, and the periphery of the groove is provided with a metal layer formed by removing the metal layer formed in the other surface of the ceramic block in a ring shape with annular grooves formed at intervals.

The ceramic waveguide duplexer may further include at least one resonance groove formed in a groove form at a position of a predetermined at least one of the plurality of resonance cavities in one face of the ceramic block, and the metal layer is formed to an inner wall.

The ceramic waveguide duplexer may further include at least one coupling hole formed through the ceramic block between at least two of the plurality of resonant cavities adjacent to each other, and formed in a stepped hole structure having a hole diameter smaller on the other side than on the one side of the ceramic block, the inner side being formed with the metal layer.

Technical effects

Therefore, the ceramic waveguide duplexer according to the present invention is capable of stably operating in a wide band with a small risk of breakage of a ceramic block and capable of being manufactured in a small size by using a common resonator having an interface formed in a hole pattern of a stepped structure capable of inputting and outputting a signal of a wide band required for the duplexer.

Drawings

Fig. 1 is a schematic diagram showing an example of a conventional monolithic ceramic waveguide filter;

FIG. 2 shows a cross-sectional view of an input/output port with respect to the ceramic waveguide filter of FIG. 1;

FIG. 3 illustrates an upper perspective view of a monolithic ceramic waveguide duplexer, according to one embodiment of the present invention;

FIG. 4 shows a top view of the monolithic ceramic waveguide duplexer of FIG. 3;

FIG. 5 shows a side cross-sectional view of the monolithic ceramic waveguide duplexer of FIG. 3;

FIG. 6 shows a side cross-sectional view of an interface aperture with respect to the shared aperture resonator structure of FIG. 3;

fig. 7 is a schematic diagram for explaining frequency bands of signals input and output from the interface hole of fig. 6;

fig. 8 shows an upper perspective view of a monolithic ceramic waveguide duplexer according to another embodiment of the present invention;

FIG. 9 shows a top view of the monolithic ceramic waveguide duplexer of FIG. 8;

FIG. 10 shows a side cross-sectional view of the monolithic ceramic waveguide duplexer of FIG. 8;

fig. 11 is a schematic diagram showing an example of an interface substrate for inputting and outputting signals to and from the monolithic ceramic waveguide duplexer of fig. 8;

FIG. 12 shows a top view of the interface substrate of FIG. 11;

FIG. 13 illustrates a side cross-sectional view of the interface substrate of FIG. 11;

fig. 14 is a schematic view showing a structure in which the monolithic ceramic waveguide duplexer of fig. 8 and the interface substrate of fig. 11 are combined.

Description of the reference numerals

200. 300: ceramic blocks 211 to 215, 311 to 319: resonant cavity

221. 222, 321 to 313: through partition walls 231, 232, 331 to 338: resonant tank

341: transmission interface 342: receiving interface

251. 351, 352: annular grooves 260, 360: metal layer

270. 370: shared interfaces 381, 382: coupling hole

400: interface substrates 431, 441, 451: transmission line

432. 442, 452: signal boards 433, 443, 453: annular groove of plate

434. 444, 454: through hole electrode

Detailed Description

For a fuller understanding of the invention, as well as the advantages of the invention's action and objects attained by its practice, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, thereby explaining the present invention in detail. However, the invention may be embodied in many different forms and is not limited to the embodiments described. In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals denote the same components in the figures.

In the entire specification, if a certain portion "includes" a certain constituent element, it means that other constituent elements may be included unless otherwise specified. The terms "…", "…", "module", "block", and the like in the specification denote units for processing at least one function or action, and may be implemented by hardware or software, or a combination of hardware and software.

Fig. 3 illustrates an upper perspective view of a monolithic ceramic waveguide duplexer, fig. 4 illustrates a top view of the monolithic ceramic waveguide duplexer of fig. 3, and fig. 5 illustrates a side sectional view of the monolithic ceramic waveguide duplexer of fig. 3, according to an embodiment of the present invention. And fig. 6 shows a side sectional view of the interface hole of fig. 3 with respect to the common hole resonator structure, and fig. 7 is a schematic diagram for explaining a frequency band of a signal input/output from the interface hole of fig. 6.

Referring to fig. 3 to 5, the monolithic ceramic waveguide duplexer of the present embodiment is also implemented as an integrated type including a plurality of resonant cavities 211 to 215 defined by a plurality of through barrier ribs 221, 222 formed to penetrate between one face and the other face of a single ceramic block 200 in a predetermined pattern, similarly to the monolithic ceramic waveguide filter shown in fig. 1.

In the ceramic block 200, the ceramic block 100 is divided into 5 partitions by 2 through partition walls 221 and 222 formed to penetrate the ceramic block 200 in a T shape on both sides. Thus defining 5 resonant cavities 211-215. Of the 2T-shaped through partition walls 221 and 222, the first through partition wall 221 partitions the first to third cavities 211 to 213 in the ceramic block 200, and the second through partition wall 222 partitions the first cavity 211 and the fourth and fifth cavities 214 and 215 in the ceramic block 200.

Here, the through- walls 221 and 222 are formed in a T-shape through the ceramic block 200 as an example, but the plurality of through- walls 221 and 222 may be formed in a straight line shape spaced apart from each other, or may be formed in a plurality of branch pattern shapes such as a Y-shape or a cross shape, in addition to the T-shape. Here, the through partition walls 221 and 222 are not formed to be spaced apart from each other but not to the side boundary of the ceramic block 200, and thus the plurality of resonant cavities 211 to 215 are not completely separated by the through partition walls. Therefore, the adjacent ones of the plurality of resonators 211 to 215 divided by the through- walls 221 and 222 can be coupled to each other by the region where the through- walls 221 and 222 are not formed. In this regard, the penetrating partitions 221 and 222 define not only the cavities 211 to 215 by simply dividing the ceramic block 200, but also signal transmission paths for transmitting signals by coupling between the cavities 211 to 215.

The duplexer performs an operation of separating a transmission signal (TX) and a reception signal (RX) according to frequency in order to transmit and receive signals using a common antenna. In contrast, in the duplexer according to the present embodiment shown in fig. 3 to 5, the first to fifth resonators 211 to 215 divided by the through partition walls 221, 222 may be formed in a laterally symmetrical structure to both sides of the ceramic block 200, and the first resonator 211 located at the center is a common resonator serving as a common path for transmitting a transmission signal (TX) to the common antenna through the common interface 270 and applying a reception signal (RX) from the common antenna, and may be referred to as a common resonator. It will be apparent to those skilled in the art that the present invention is not limited to laterally symmetrical ceramic blocks. And wherein the third and second resonators 213, 212 located at one side of the first resonator 211 are assumed to form a transmission path for sequentially transmitting a transmission signal (TX) transmitted from a transmitter (not shown) to the first resonator 211, and the fourth and fifth resonators 214, 215 located at the other side of the first resonator 211 are assumed to form a reception path for sequentially transmitting a reception signal (RX) transmitted from the first resonator 211 to a receiver (not shown).

Wherein the first to third resonators 211 to 213 function as Band Pass Filters (BPFs) corresponding to the frequency bands of the transmission signal (TX) such that the reception signal (RX) is not transferred to the transmitter, and the first, fourth and fifth resonators 211, 214, 215 function as BPFs corresponding to the frequency bands of the reception signal (RX) such that the transmission signal (TX) is not transferred to the receiver.

However, the 2 through- walls 221, 222 do not completely divide the first resonator 211 and the adjacent third and fifth resonators 213, 215, so that on the one hand a coupling of the first resonator 211 with the second and fourth resonators 212, 214 is achieved and also a cross coupling with the third and fifth resonators 213, 215 is achieved. This cross coupling generates Transmission-Zero (Transmission-Zero) at a frequency lower than the passband, and can improve the attenuation characteristics of the ceramic waveguide duplexer.

Further, at least one of the plurality of resonators 211 to 215 (for example, the third and fifth resonators 213 and 215) may be formed with resonance grooves 231 and 232. The resonance grooves 231, 232 may be formed at one side of the ceramic block 200, with a groove formed in a circular shape as an example. However, the form of the resonance grooves 231 and 232 may be variously modified. Here, each of the resonance grooves 231, 232 may be formed at the center of the electric field concentration in the region corresponding to the resonance cavities 213, 215. This is because the effect of lowering the resonance frequency is induced by increasing the capacitance component of each of the plurality of resonators 211 to 215, so that the size of the ceramic waveguide duplexer can be reduced compared with the case where the resonance grooves 231 and 232 are not formed.

In addition, at least one interface may be formed in the ceramic waveguide duplexer of the present embodiment. The duplexer is an input/output port for inputting/outputting signals to/from a transmitter, a receiver, and a common antenna, and requires 3 interfaces. A transmitting interface (not shown) among the 3 interfaces receives a transmitting signal (TX) from a transmitter, a receiving interface (not shown) delivers a receiving signal (RX) to a receiver, and a common interface 270 inputs and outputs the transmitting signal (TX) or the receiving signal (RX) to a common antenna (not shown).

Although the transmission interface and the reception interface are not separately shown for convenience of explanation, the transmission interface and the reception interface may be formed in 2 resonators (the third and fifth resonators 213 and 215 among them) to which signals should be input or output among the plurality of resonators 211 to 215, and may be formed in the form of grooves at the positions of the corresponding resonators 231 and 232 in the other surface of the ceramic block 200, similarly to the interface grooves 141 and 142 shown in fig. 1 and 2. In the case where the transmission interface and the reception interface, such as the interface grooves 141 and 142, are formed in the form of grooves, the transmission interface and the reception interface transfer signals with the respective corresponding resonance grooves 231 and 232 by capacitive coupling.

However, in the case where signals are input and output by using a coaxial cable or the like, the inner conductor of the coaxial cable is directly inserted into a predetermined position in the ceramic block 200, and thus signals can be transmitted by capacitive coupling to the corresponding resonant grooves 231 and 232. Therefore, the transmission interface and the reception interface may not be formed in a specific shape according to circumstances, and may be omitted as shown in fig. 3 to 5.

In addition, the entire outer face of the single ceramic block 200 is formed with a metal layer 260. The metal layer 260 is also formed inside the plurality of through- walls 221 and 222 and the plurality of resonance grooves 231 and 232. However, in the case where the transmitting interface and the receiving interface are formed in the form of grooves, as shown in fig. 1, annular grooves may be formed so as to remove the metal layer 260 toward the periphery of the grooves. That is, the transmitting interface and the receiving interface may have the same configuration as those of the conventional monolithic ceramic waveguide filter.

However, in the present embodiment, unlike the conventional interface configuration, the common interface 270 is formed in the form of a hole (hole) penetrating the ceramic block 200. In particular, as shown in fig. 5 and 6, the common interface 270 has a step structure in which the diameter of one surface side of the ceramic block 200 is larger than the diameter of the other surface side of the hole formed through the ceramic block 200.

Referring to fig. 6, the common interface 270 is basically formed in a cylindrical hole shape penetrating the ceramic block 200, but is formed in a multi-step structure having a plurality of step regions 272a, 272b that are expanded stepwise with an upper diameter on one side of the ceramic block 200 larger than a lower diameter 271 on the other side. Although the common interface 270 is shown to have a multi-step structure in which the diameter increases stepwise from the other surface side to the one surface side of the ceramic block 200, it may be formed in a single step structure as the case may be.

Also, a metal layer 261 is formed inside the hole-shaped common interface 270. However, annular grooves 251 are formed toward the periphery of the common interface 270 in the other surface side of the ceramic block 200 such that the metal layer 261 formed inside the common interface 270 is spaced apart from the metal layer 260 formed outside the common interface 270 in the other surface side of the ceramic block 200. Here, the annular groove 251 may be formed such that an inner circle is spaced apart from the Kong Xiangge of the common interface 270 at a predetermined interval from the other surface of the ceramic block 200 such that the metal layer 261 formed at the inside of the common interface 270 is extended to a portion of the other surface of the ceramic block 200. This is to enable the common interface 270 to input and output signals to and from a planar line type input/output terminal formed on a PCB or the like, in addition to an input/output terminal such as a coaxial cable which is inserted therein to be able to transmit signals.

At the same time, the stepped regions 272a, 272b are also formed with ring-shaped inner grooves 273 that isolate the metal layer formed inside the common interface 270 from the metal layer formed on one side of the ceramic block 200 so as to be spaced apart from each other. Among them, the inner annular grooves 273 formed in the stepped regions 272a, 272b expand the frequency band of the signal input and output through the common interface 270 together with the multi-step hole structure. As shown in fig. 6, the inner annular groove 273 may be formed parallel to one face of the ceramic block 200 at the stepped regions 272a, 272 b. By forming the inner annular groove 273, the common interface 270 together through the metal layer 261 formed therein transmits signals in a capacitively coupled manner. The frequency band of the signal that can be transmitted in a capacitively coupled manner can be adjusted in this case according to the width of the inner annular groove 273.

In this way, the common port 270 is formed in a hole shape having a stepped structure, and one stepped region is formed with an inner annular groove 273, so that when a signal is transmitted by capacitive coupling, the frequency band of the signal that can be transmitted is greatly widened.

As described above, the duplexer receives a transmission signal (TX) and a reception signal (RX) of different frequency bands to perform band pass filtering. The transmission interface receives and transmits only the transmission signal (TX), and the reception interface receives and transmits only the reception signal (RX). Accordingly, as shown in fig. 7, the transmission interface may be configured to input and output a signal of a transmission band (TX band), and the reception interface may be configured to output and output a signal of a reception band (RX band).

However, the common interface 270 for inputting and outputting the transmission signal (TX) and the reception signal (RX) to and from the common antenna needs to be configured to cover both the transmission band (TX band) and the reception band (RX band). That is, a frequency band in which signals can be input and output is required to be extremely large compared with a transmission interface or a reception interface. For example, in the case where the transmission band (TX band) and the reception band (RX band) are 300MHz, as shown in fig. 7, the band (required band) required for the shared interface 270 should not be a 600MHz of the sum of the transmission band (TX band) and the reception band (RX band) but should include a transmission/reception guard band (TRX guard band) set for distinguishing the transmission signal (TX) and the reception signal (RX). That is, the shared interface 270 is configured to be capable of inputting and outputting signals of a frequency band corresponding to the sum of a transmission frequency band (TX band), a reception frequency band (RX band), and a transmission/reception guard band (TRX guard band).

As shown in fig. 2, when the corresponding resonance grooves 131 and 136 and the interface grooves 141 and 142 are formed so as to face each other in the direction of one surface and the other surface of the ceramic block 100, the smaller the gap g between the resonance grooves 131 and 136 and the interface grooves 141 and 142 is, the larger the capacitance formed by capacitive coupling is, and the frequency band of the signal that can be input and output is also increased. However, even if the interval g between the resonance grooves 131, 136 and the interface grooves 141, 142 is continuously reduced, the expandable band is limited. When the gap g between the resonance grooves 131 and 136 and the interface grooves 141 and 142 is very small (for example, 2mm or less), there is a risk of breakage of the ceramics in the region during firing or during operation.

In contrast, in the present embodiment, the common interface 270 is formed in a hole pattern penetrating the stepped structure of the ceramic block 200, and by adjusting the frequency band forming capacitive coupling to the width of the inner annular groove 273 formed in one of the stepped regions, a wide band signal of the order of 800MHz can be transmitted without risk of breakage. Therefore, the broadband transfer characteristics required for the interface 270 of the duplexer can be stably realized, and the integrated ceramic waveguide duplexer can be miniaturized.

Fig. 8 illustrates an upper perspective view of a monolithic ceramic waveguide duplexer according to another embodiment of the present invention, fig. 9 illustrates a top view of the monolithic ceramic waveguide duplexer of fig. 8, and fig. 10 illustrates a side sectional view of the monolithic ceramic waveguide duplexer of fig. 8.

The monolithic ceramic waveguide duplexer shown in fig. 8 to 10 is also formed as an integrated body like the duplexer shown in fig. 3 to 5, and includes a plurality of resonant cavities 311 to 319, 31X defined by a plurality of penetrating partition walls 321 to 323 formed to penetrate between one surface and the other surface of a single ceramic block 300.

The first through partition 321 among the plurality of through partition walls 321 to 323 has a form of two cross-connected parts, so that the first resonator 311 and the X-th resonator 31X in the center of the ceramic block 300 are divided from the resonators 312 to 315 and 316 to 319 located on both sides, and the first resonator 311 and the X-th resonator 31X are divided from each other. The first resonator 311 transmits the transmission signal (TX) to the common antenna through the common interface 370, and is a common resonator serving as a common path for applying the reception signal (RX) from the common antenna, and may be referred to as a common resonator.

The second penetrating partition 322 formed in a cross shape divides the 4 resonators 312 to 315 located on one side in the ceramic block 300 from each other, and the third penetrating partition 323 formed in a cross shape similarly divides the 4 resonators 312 to 315 located on the other side in the ceramic block 300 from each other.

Wherein it is assumed that the 4 resonators 312 to 315 located at one side form a transmission path for transmitting a transmission signal (TX) applied at the transmitter to the first resonator 311, and the 4 resonators 316 to 317 located at the other side form a reception path for transmitting a reception signal (RX) applied at the transmitter to the first resonator 311. That is, the first to fifth resonators 311 to 315 function as BPFs corresponding to the frequency band of the transmission signal (TX) so that the reception signal (RX) is not transmitted to the transmitter, and the first to sixth to ninth resonators 311, 316 to 319 function as BPFs corresponding to the frequency band of the reception signal (RX) so that the transmission signal (TX) is not transmitted to the receiver. The X-th resonator 31X is an unusable area generated when the division of the first resonator 311 is divided.

In addition, resonance grooves 331 to 338 are formed on one surface side of the ceramic block 300 of each of the 8 resonance cavities 312 to 319 located on both sides in the duplexer shown in fig. 8 to 10. The respective resonance grooves 331 to 338 can reduce the size of the resonance chambers 312 to 319 by increasing the capacitance components of the corresponding resonance chambers 312 to 319 to induce an effect of reducing the resonance frequency. Namely, enabling miniaturization of the duplexer. On the other surface side of the ceramic block 300, a transmission port 341 having a groove shape is formed at a position corresponding to the resonance groove 334 of the fifth resonance chamber 315 among the plurality of resonance chambers 311 to 319, and a reception port 342 having a groove shape is formed at a position corresponding to the resonance groove 338 of the ninth resonance chamber 319. The transmission interface 341 and the reception interface 342 in the form of grooves form capacitive coupling together with the resonance grooves 334 and 338 formed in the fifth resonance chamber 315 and the ninth resonance chamber 319 to transmit signals, similarly to the interface grooves 141 and 142 shown in fig. 1.

Here, annular grooves 351 and 352, which are areas where the metal layer 160 is removed, are formed on the other surface of the ceramic block 300 toward the periphery of each of the transmission port 341 and the reception port 342 in the form of grooves. The inner circles of the annular grooves 351, 352 may be formed to correspond to the sizes of the grooves forming the transmitting and receiving interfaces 341, 342, but the inner circles may also be formed to be spaced apart from the grooves by a predetermined interval from the edges such that the metal layers inside the transmitting and receiving interfaces 341, 342 are formed to a partial region of the other surface of the ceramic block 300 so as to input and output signals with planar line-type input and output terminals formed on a PCB or the like.

In addition, a common interface 370 for inputting and outputting a transmission signal (TX) and a reception signal (RX) to and from a common antenna is formed in the first resonant cavity 311. Also in the duplexer shown in fig. 8 to 10, since the first resonator 311 is a common resonator that transfers a transmission signal (TX) to the common antenna and receives a reception signal (RX) from the common antenna, a common interface 370 is formed in the first resonator 311. The common interface 370 is formed in a hole pattern having a stepped structure with a larger diameter on one side than the other side of the ceramic block 300, and may be formed in a single stepped structure or a multi-stepped structure, as in the common interface 270 shown in fig. 3 to 5. And, at least one stepped region of the common interface 370 is formed with an inner annular groove parallel to one surface of the ceramic block 300 so that a signal can be transferred in a broadband in a capacitive coupling manner. Here, the first to third through barrier ribs 321 to 322 are spaced apart from each other, and cross coupling is formed between the second resonator 312 and the fifth resonator 315 and between the sixth resonator 316 and the ninth resonator 319, whereby transmission zero occurs at a frequency lower than the passband to improve the attenuation characteristics of the ceramic waveguide duplexer.

In the duplexer having the above configuration, the transmission signal (TX) applied through the transmission interface 341 is transmitted to the resonance tank 334 formed in the fifth resonance chamber 315 in a capacitive coupling manner, the transmission signal (TX) transmitted to the fifth resonance chamber 315 is transmitted to the first resonance chamber 311 after being band-pass filtered in a capacitive coupling manner sequentially through the fourth, third and second resonance chambers 314, 313, 312, and the common interface 370 of the first resonance chamber 311 transmits the transmitted transmission signal (TX) to the common antenna. The reception signal (RX) transmitted from the common antenna to the common interface 370 is transmitted through the sixth to ninth resonant cavities 319 in turn in a capacitive coupling manner, and the reception interface 342 formed in the ninth resonant cavity 319 and the resonant tank 338 output the reception signal to the connected output terminal in a capacitive coupling manner.

In addition, the diplexer shown in fig. 8 to 10 may be further formed with at least one coupling hole 381, 382 penetrating the ceramic block 300 between the adjacent ones of the plurality of resonant cavities 311 to 319. As an example, the coupling holes 381, 382 are shown as being formed between the third and fourth resonators 313, 314 and between the seventh and eighth resonators 317, 318, but the coupling holes 381, 382 may be formed between the other resonators adjacent to each other. Also, the respective coupling holes 381, 382 may be formed in a single-step or multi-step structure in which the diameter of one side of the ceramic block 300 is larger than that of the other side, similar to the common interface 370. The coupling holes 381, 382 function to convert a sign suitable for cross coupling between the resonance grooves 331, 334 or between the resonance grooves 335, 338 into minus (-) so that capacitive cross coupling in which transmission zeros are formed at the lower side of the pass band is achieved.

Can be formed in a small size and can further lower the resonance frequency by being formed between adjacent resonance cavities. Thereby, it is possible to adapt to further miniaturization of the duplexer together with the resonance grooves 331 to 338.

As described above, the diplexer of the present embodiment is integrally formed in the single ceramic blocks 200 and 300, and the plurality of resonators 212 to 215 and 312 to 319 formed on both sides centering on the first resonators 211 and 311 located at the centers of the ceramic blocks 200 and 300 form transmission paths and reception paths through which the transmission signal (TX) and the reception signal (RX) are respectively band-pass filtered and transferred. Here, the common interfaces 270 and 370 having a hole pattern with a stepped structure are formed in the first resonators 211 and 311 as common resonators connected to the common antenna, and thus, signals can be input and output in a wide band, and thus, a transmission signal (TX) and a reception signal (RX) can be stably input and output.

Although only the common interfaces 270, 370 are shown in the hole form formed in the stepped structure, the transmission interface and the reception interface may also be formed in the hole form in the stepped structure as the common interfaces 270, 370, as the case may be.

Fig. 11 shows an example of an interface substrate for inputting and outputting signals to and from the monolithic ceramic waveguide duplexer of fig. 8, fig. 12 shows a plan view of the interface substrate of fig. 11, and fig. 13 shows a side sectional view of the interface substrate of fig. 11. And fig. 14 shows a structure in which the monolithic ceramic waveguide duplexer of fig. 8 and the interface substrate of fig. 11 are combined.

As described above, in the monolithic ceramic waveguide duplexer according to the present embodiment, the inner circles of the annular grooves 351, 352 are formed to be spaced apart from the outer contours of the grooves or holes of the transmitting and receiving interfaces 341, 342 and the common interfaces 270, 370 by a predetermined interval. The internal metal layer 261 of the transmission interface 341, the reception interface 342, and the common interfaces 270 and 370 is formed so as to extend to the other surfaces of the ceramic blocks 200 and 300, so that signals can be input and output not only to and from the input/output terminals in the form of coaxial cables but also to and from the planar line-type input/output terminals of the substrate structure.

In fig. 11 to 13, in order to realize a planar line type input/output terminal, the interface board 400 is implemented as a stripline (stripline) as an example. The interface substrate 400 of the stripline structure is implemented as a dielectric plate 410 and a 3-layer structure in which metal plates 421 and 422 are formed on one surface and the other surface of the dielectric plate 410, respectively. In addition, signal plates 432, 442, 452 and plate annular grooves 433, 443, 453 of the metal plate 421, which are removed by a predetermined interval from the periphery of the signal plate, are formed in regions corresponding to the common interfaces 270, 370 and the transmission and reception interfaces 341, 342 of the diplexer, respectively, on one surface of the interface substrate 400, so that the metal plate 421 and the signal plates 432, 442, 452 are electrically isolated.

In addition, the dielectric plate 410 is internally formed with positions formed to be connected to the signal plates 432, 442, 452 so that a transmission signal (TX) and a reception signal (RX) are transferred, and through- hole electrodes 434, 444, 454 are formed between the signal plates 432, 442, 452 corresponding to one ends of the respective transmission lines 431, 441, 451 to electrically connect the signal plates 432, 442, 452 corresponding to the transmission lines 431, 441, 451.

As shown in fig. 14, the interface board 400 having such a structure is bonded to the other surface of the ceramic waveguide duplexer, and in this case, the 3 signal boards 432, 442, 452 are electrically connected in contact with the internal metal layer 261 formed by extending the insides of the common interfaces 270, 370 and the transmission and reception interfaces 341, 342 to the other surfaces of the ceramic blocks 200, 300, respectively. Therefore, the common interfaces 270 and 370 and the transmission interface 341 and the reception interface 342 can input and output signals to and from the corresponding transmission lines 431, 441 and 451 through the 3 signal boards 432, 442 and 452. That is, signals can be easily input and output to and from the diplexer through the planar line type input/output terminals other than the input/output terminals of the coaxial cable.

The invention has been described with reference to the embodiments shown in the drawings, but this is only an example, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments can be made therefrom.

The true technical scope of the invention is therefore determined by the technical ideas of the scope of the appended claims.

Claims (10)

1. A ceramic waveguide duplexer, comprising:

a plurality of resonators defined by a plurality of partitions formed by penetrating through one surface and the other surface of the single ceramic block in a predetermined pattern;

a common interface formed in a hole structure penetrating the ceramic block in a region of a common resonator which inputs and outputs signals to and from the common antenna among the plurality of resonators, and in a stepped hole structure having a hole diameter on the other surface side of the ceramic block smaller than that on the one surface side; and

and the metal layer is formed on the outer surface of the ceramic block, and the annular shape is removed from the step area parallel to one surface of the ceramic block in the common interface of the step hole structure to form an inner annular groove.

2. The ceramic waveguide diplexer of claim 1, wherein:

the common interface is formed in a hole shape of a multi-step structure in which the diameter is repeatedly reduced in steps from one surface side of the ceramic block.

3. The ceramic waveguide diplexer of claim 1, wherein:

the width of the inner annular groove is adjusted according to the frequency band of the signal input to and output from the common antenna.

4. The ceramic waveguide diplexer of claim 3, wherein:

the metal layer is formed with an annular groove removed from the other surface of the ceramic block and having an annular shape with an inner circle spaced apart from the hole periphery of the common port by a predetermined interval.

5. The ceramic waveguide diplexer of claim 1, wherein:

the plurality of resonant cavities are formed in a symmetrical structure to both sides of the ceramic block by the plurality of penetrating partition walls, and the common resonant cavity is located on a central axis of the ceramic block symmetrical to both sides.

6. The ceramic waveguide diplexer of claim 5, wherein:

the predetermined transmitting resonant cavity in the plurality of resonant cavities carries out band-pass filtering on the applied transmitting signal to the adjacent resonant cavity in a capacitive coupling mode so as to be transmitted to the common resonant cavity, and the common resonant cavity carries out band-pass filtering on the applied receiving signal to the adjacent resonant cavity in a capacitive coupling mode so as to be transmitted to the predetermined receiving resonant cavity.

7. The ceramic waveguide diplexer of claim 6, wherein:

the ceramic waveguide duplexer further comprises a transmitting interface and a receiving interface,

the transmitting interface and the receiving interface penetrate through the ceramic block in the respective areas of the transmitting resonant cavity and the receiving resonant cavity, the ceramic block is provided with a stepped hole structure with the diameter smaller than that of one side on the other side of the ceramic block, and an inner annular groove with the metal layer removed in an annular shape is formed in a stepped region parallel to one side of the ceramic block in the stepped hole structure.

8. The ceramic waveguide diplexer of claim 6, wherein:

the ceramic waveguide duplexer further comprises a transmitting interface and a receiving interface,

the transmitting interface and the receiving interface are formed in a groove shape at the positions of the transmitting resonant cavity and the receiving resonant cavity on the other surface of the ceramic block, and the periphery of the groove is provided with metal layers which are formed at intervals by annular grooves removed in an annular shape through the metal layers formed on the other surface of the ceramic block.

9. The ceramic waveguide diplexer of claim 1, wherein:

the ceramic waveguide diplexer also includes at least one resonant tank,

the at least one resonance groove is formed in a groove form at a position of a predetermined at least one resonance cavity among the plurality of resonance cavities in one face of the ceramic block, and the metal layer is formed to the inside.

10. The ceramic waveguide diplexer of claim 1, wherein:

the ceramic waveguide diplexer also includes at least one coupling hole,

the at least one coupling hole is formed to penetrate the ceramic block between at least two adjacent resonant cavities among the plurality of resonant cavities, and is formed in a stepped hole structure in which a hole diameter on the other surface side of the ceramic block is smaller than a hole diameter on the one surface side, and the metal layer is formed on the inner surface side.

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