Antenna filter in wireless communication system and electronic device including the same

Abstract

The disclosure relates to a fifth generation (5G) or pre-5G communication system for supporting a higher data transfer rate than a fourth generation (4G) communication system such as long term evolution (LTE). According to various embodiments of the disclosure, an antenna module includes a filter for filtering a radio frequency (RF) signal, and a sub-printed circuit board (PCB) including a passive circuit for processing the RF signal, and the sub-PCB can be coupled to the filter so as to operate as a buffer when the filter is coupled to a filter board.

Description

TECHNICAL FIELD

[0001] The disclosure relates generally to a wireless communication system, and more particularly, to an antenna filter in a wireless communication system and an electronic device including the same. BACKGROUND

[0002] To meet the demand for wireless data traffic soaring since deployment of 4G communication systems, efforts have been made to develop an improved 5G or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a 'Beyond 4G Network' or a 'Post Long Term Evolution (Post-LTE) System'.

[0003] The 5G communication system is considered to be implemented in higher frequency (i.e., FR1 (e.g., 3.5 GHz band) corresponding to a third generation partnership project (3GPP) frequency range 1 (FR1) and a super high frequency (mmWave) band (i.e., FR2 (e.g., 28 GHz and 60 GHz bands) corresponding to a 3GPP frequency range 2 (FR2)) to achieve a higher data rate beyond the 6G. In the super high frequency band, to reduce propagation loss of radio waves and increase a transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beam forming, large scale antenna techniques are discussed in the 5G communication system.

[0004] In addition, in the 5G communication system, development for system network improvement is under way based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, a device to device (D2D) communication, a wireless backhaul, a moving network, a cooperative communication, coordinated multi-points (CoMP), a reception-end interference cancellation and the like.

[0005] In the 5G system, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), a non-orthogonal multiple access (NOMA), and a sparse code multiple access (SCMA) as an advanced access technology have been developed.

[0006] To improve communication performance, products equipped with multiple antennas are being developed, and it is expected that devices using a much larger number of antennas will be used by taking advantage of massive MIMO technology. As the number of antenna elements in a communication device increases, the number of RF components (e.g., filters, etc.) inevitably increases accordingly. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] Based on the above description, the disclosure provides an apparatus and method for a filter module in a wireless communication system.

[0009] Further, the disclosure provides a structure of a filter module in a wireless communication system, including a printed circuit board (PCB) for buffering between a filter board on which a plurality of filters are arranged and a radio frequency (RF) filter.

[0010] Further, the disclosure also provides an apparatus in which a passive circuit is implemented on a PCB for buffering between a filter board and a radio frequency (RF) filter in a wireless communication system, and a method of implementing the apparatus.

[0011] Technical solutions

[0012] An antenna filter module can include a filter for filtering a radio frequency (RF) signal, and a sub-printed circuit board (PCB), wherein the sub-PCB includes a passive circuit configured to process the RF signal, and the sub-PCB is coupled to the filter so as to operate as a buffer when the filter is coupled to a filter board.

[0013] A massive multiple-input multiple-output (massive MIMO) unit (MMU) apparatus in a wireless communication system can include at least one processor configured to process a signal, a plurality of radio frequency (RF) filter modules configured to filter a signal, and an antenna array configured to radiate a signal, wherein an RF filter module of the plurality of RF filter modules includes a filter configured to filter an RF signal, and a sub-printed circuit board (PCB) coupled to the filter, the sub-PCB including a passive circuit configured to process the RF signal, and the sub-PCB being coupled to the filter so as to operate as a buffer when the filter is coupled to a filter board.

[0014] Advantages of the present invention

[0015] The apparatus and method according to various embodiments of the disclosure can reduce the area of a filter board while preventing cracks due to coupling through a filter module including a radio frequency (RF) filter and a PCB for buffering between a filter board and the RF filter.

[0016] The advantages obtainable from the disclosure can not be limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those skilled in the art to which the disclosure pertains from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 a A wireless communication system according to various embodiments of the disclosure is illustrated.

[0018] Figure 1 bAn example of an antenna array in a wireless communication system according to various embodiments of the disclosure is illustrated.

[0019] Figure 2 An example of a circuit of a calibration network PCB for beamforming according to an embodiment of the disclosure is illustrated.

[0020] Figure 3 An example of a structure of an antenna module according to an embodiment of the disclosure is illustrated.

[0021] Figure 4 An example of a filter module according to an embodiment of the disclosure is illustrated.

[0022] Figures 5a to 5d An example of a passive circuit provided on a buffer PCB of a filter module according to an embodiment of the disclosure is illustrated.

[0023] Figure 6 An effect of reducing an area of a filter board due to a filter module according to an embodiment of the disclosure is illustrated.

[0024] Figures 7a to 7c An example of a connection structure of a filter module and a filter board according to an embodiment of the disclosure is illustrated.

[0025] Figure 8 An example of a via port of a filter module according to an embodiment of the disclosure is illustrated.

[0026] Figure 9 A functional element of an electronic device including a filter module according to various embodiments of the disclosure is illustrated. DETAILED DESCRIPTION

[0027] The terms used in the present disclosure are merely used to describe particular embodiments, and are not intended to limit the present disclosure. Singular expressions can include plural expressions, unless they are absolutely different in the context. Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure pertains. The terms defined in generally used dictionaries can be interpreted as having the same meaning as the contextual meaning in the relevant art, and should not be interpreted as having ideal or excessively formal meanings unless expressly defined in the present disclosure. In some cases, even the terms defined in the present disclosure should not be interpreted to exclude embodiments of the present disclosure.

[0028] Hereinafter, various embodiments of the present disclosure will be described in terms of a method using hardware. However, various embodiments of the present disclosure include technology using both hardware and software, and thus, various embodiments of the present disclosure can not exclude aspects of software.

[0029] As used in the following description, terms exemplifying components of an electronic device (e.g., a substrate, a board, a printed circuit board (PCB), a flexible PCB (FPCB), a module, an antenna, an antenna element, a circuit, a processor, a chip, an element, and a device), terms exemplifying shapes of components (e.g., a tuning member, a tuning structure, a tuning structure body, a structure, a supporting unit, a contact unit, a protrusion, an opening), terms exemplifying connection units between structures (e.g., a connection unit, a contact unit, a supporting unit, a contact structure, a conductive member, and a component), and terms exemplifying circuits (e.g., a transmission line, a PCB, an FPCB, a signal line, a feeding line, a data line, an RF signal line, an antenna line, an RF path, an RF module, and an RF circuit) are used for convenience of description. Accordingly, the present disclosure is not limited to the terms described below, and other terms having equivalent technical meanings can be used. Also, terms such as "…unit", "…device", "…material", or "…body" used below can mean at least one shaped structure or unit for processing a function.

[0030] As used in the present disclosure, the expressions "greater than" or "less than" are used to determine whether a certain condition is satisfied or achieved, but this is only for the purpose of illustrating one example, and does not exclude "greater than or equal to" or "equal to or less than". A condition indicated by the expression "greater than or equal to" can be replaced by a condition indicated by "greater than", a condition indicated by the expression "equal to or less than" can be replaced by a condition indicated by "less than", and a condition indicated by "greater than and equal to or less than" can be replaced by a condition indicated by "greater than and less than".

[0031] Also, in the present disclosure, terms adopted in some communication standards (e.g., the 3rd Generation Partnership Project (3GPP) and the Institute of Electrical and Electronics Engineers (IEEE)) will be used to describe various embodiments, but they are only for the purpose of illustration. Embodiments of the present disclosure can also be easily applied to other communication systems by modification.

[0032] Hereinafter, the present disclosure relates to an antenna filter and an electronic device including the filter in a wireless communication system. In particular, the present disclosure describes a technology of implementing miniaturization of a filter board by implementing a passive circuit on a PCB as a buffer between the filter board and an RF filter in a wireless communication system. According to an embodiment, the filter board can include a PCB for an antenna filter unit (AFU). According to an embodiment, the filter board can include a PCB for calibrating beamforming.

[0033] Figure 1 a A wireless communication system according to various embodiments of the present disclosure is illustrated. In Figure 1 aIn a wireless communication environment 100 according to the present disclosure, a base station 110 and a terminal 120 are shown as nodes using a wireless channel.

[0034] The base station 110 is a network infrastructure that provides wireless access for the terminal 120. The coverage of the base station 110 is defined as a predetermined geographical area based on a distance at which a signal can be transmitted. The base station 110 can be referred to as a "Massive Multiple-Input Multiple-Output (Massive MIMO) Unit (MMU)", an "Access Point (AP)", an "eNodeB (eNB)", and a "5th-Generation Node (5G Node)", a "5G NodeB (NB)", a "wireless point", a "Transmission / Reception Point (TRP)", an "access unit", a "Distributed Unit (DU)", a "Transmission / Reception Point (TRP)", a "Radio Unit (RU)", a "Remote Radio Head (RRH)", or other terms having equivalent technical meanings. The base station 110 can transmit a downlink signal and can receive an uplink signal.

[0035] The terminal 120 is a device used by a user and communicates with the base station 110 through a wireless channel. In some cases, the terminal 120 can operate without user intervention. That is, the terminal 120 is a device that performs Machine Type Communication (MTC) and can not be carried by a user. The terminal 120 can be referred to as a "User Equipment (UE)", a "mobile station", a "subscriber station", a "Customer Premises Equipment (CPE)", a "remote terminal", a "wireless terminal", an "electronic device", a "vehicle terminal", a "user device", or other terms having equivalent technical meanings, in addition to being referred to as a terminal.

[0036] Figure 1 b An example of an antenna array in a wireless communication system according to various embodiments of the present disclosure is shown. Beamforming is used as one of techniques to mitigate path loss of a radio wave and increase a propagation distance of a radio wave. In general, beamforming uses a plurality of antennas to concentrate a radio wave arrival area or enhance a directionality of reception sensitivity in a specific direction. Accordingly, in order to form a beamforming coverage area, rather than forming a signal in an isotropic pattern by using a single antenna, the base station 110 can have a plurality of antennas. Hereinafter, an antenna array having a plurality of antennas is described. Figure 1 b The antenna array shown in FIG. 1 is only an example to describe embodiments of the present disclosure, and is not to be construed as limiting other embodiments of the present disclosure.

[0037] Referring to Figure 1 b The base station 110 can include an antenna array 130. According to an embodiment, the base station 110 can include a Massive MIMO Unit (MMU) including the antenna array 130. Each antenna included in the antenna array 130 can be referred to as an array element or an antenna element. In Figure 1 bIn the middle, the antenna array 130 is shown as a two-dimensional planar array, but this is only an example, not a limitation of other embodiments of the present disclosure. According to another embodiment, the antenna array 130 can be configured in various forms, such as a linear array. The antenna array can be referred to as a massive antenna array.

[0038] To improve communication performance, the number of antennas (or antenna elements) of an apparatus for performing wireless communication (e.g., a base station 110) is increasing. In addition, the number of RF elements (e.g., amplifiers or filters) and components for processing RF signals received or transmitted through the antenna elements is also increasing, and thus, spatial gain and cost efficiency and satisfaction of communication performance are important in configuring a communication apparatus. When the number of paths increases, the number of filters for processing signals in each antenna element also increases.

[0039] An RF filter can include a circuit that performs filtering by forming resonance to transmit a radio signal of a desired frequency. That is, the RF filter can perform a function of selectively recognizing a frequency. The RF filter is an important component that selects and attenuates a frequency and is used in most communication apparatuses. Since the RF filter is included in each path, the weight and size of the RF filter are closely related to product competitiveness.

[0040] Since a metal cavity filter performs well in terms of power handling and capacity / insertion loss / attenuation performance, the metal cavity filter is used in many communication apparatuses. However, the metal cavity filter is not easily mass-produced due to cost limitations, product size, etc., and thus, it is difficult to meet performance requirements. According to various embodiments of the present disclosure, a ceramic waveguide filter (hereinafter referred to as a ceramic filter) can be used as an RF filter. The cavity can be implemented with ceramic and plating, and a resonator is configured in each cavity. The overall size of the filter can be reduced by reducing the size of each cavity. Compared to the existing metal cavity filter, the weight and volume can be reduced, and thus, the size of the MMU can also be reduced (about 8%).

[0041] The ceramic waveguide filter can be disposed on a board (hereinafter referred to as a filter board) on which one or more filters can be disposed. When the ceramic waveguide filter and the filter board are disposed using a surface mount technology (SMT), the RF characteristics (e.g., return loss) and phase can change. Due to the change in the above-described RF characteristics, in general, in order to secure the RF characteristics of the ceramic waveguide filter, a separate tuning process (e.g., tuning processing through a matching circuit) is also required. Accordingly, various embodiments of the present disclosure provide a method of minimizing the tuning procedure.

[0042] A ceramic waveguide filter transmits a signal through a dielectric, not air. Since the inside of a ceramic waveguide filter is filled with a dielectric, miniaturization of the ceramic waveguide filter is inversely proportional to the dielectric constant. Since a dielectric is used, a harmonic resonance frequency, which means a frequency component that is a multiple of a resonance frequency, can be lowered. For example, in the case of a metal cavity filter, harmonic frequencies are generally generated at 3 to 3.5 times, but by using various shapes of filters, the harmonic resonance frequency can be adjusted to 13 to 14 GHz. However, in the case of a ceramic waveguide filter, harmonic components are generally generated at about 2 to 2.5 times. When the harmonic resonance frequency of the ceramic waveguide filter is formed within a predetermined range, a low pass filter is additionally required to meet the requirements (for example, -25 dB or less at 12.75 GHz according to the 3GPP standard). Various embodiments of the disclosure provide a method of designing an efficient antenna device by deploying a passive circuit (for example, a low pass filter) in a communication device.

[0043] Figure 2 An example of a circuit of a calibration network PCB for beamforming is shown according to embodiments of the disclosure. A plurality of antennas is used to implement beamforming. Through the plurality of antennas, the gain of beamforming can be increased, and a multiple-input multiple-output (MIMO) technology can be utilized. Using two or more antennas at both ends of transmission and reception or one of them, a communication device can obtain effects such as reduction of fading effects, large capacity, high speed, and increase of coverage, etc. In addition, channel capacity can be increased without increasing frequency bandwidth and transmission power. To achieve the above effects, the communication device can include a calibration network circuit. According to embodiments, the calibration network circuit can be used for phase control of each antenna.

[0044] Referring to Figure 2 An example of a calibration network 200 connected to an antenna is described. To provide beamforming in an antenna, the amplitude and phase in each transmission (TX) path and each reception (RX) path need to be kept constant. However, since each transmission path or each reception path has a deviation in an actual wireless module, compensation for the deviation is required. Compensation for such a deviation can be referred to as beamforming calibration. According to embodiments, a BF calibration network including a combiner 230 and a coupler capable of determining the characteristics of each path is required, respectively. The RF amplitude and phase are continuously monitored through the calibration network 200, and the change in the characteristics of the calibration network is minimized even if the environment changes. According to embodiments, the calibration network 200 can include 32 transmission paths and 32 reception paths.

[0045] Each transmit path or each receive path may have input / output ports. Each path from the input port to the output port may be referred to as main path 210. Calibration network 200 may include path 220 for feeding back the transmitted signal from each transmit path to the calibration processor, the transmitted signal being obtained via a bidirectional coupler coupled to the output of each transmit path. For transmit path calibration, the calibration processor can measure the RF characteristic (phase / amplitude / delay, etc.) deviation between each transmit path and can perform TX calibration to compensate for the measured deviation. TX calibration to compensate for the measured deviation can be performed based on the correlation between the feedback signal (obtained using a magnetic transmit signal at the rear end of the transmit path) and the transmitted signal. For receive path calibration, the calibration processor can measure the RF characteristic (phase / amplitude / delay, etc.) deviation between each receive path and can perform TX calibration to compensate for the measured deviation. By inserting a pilot signal in each receive path, RX calibration to compensate for the measured deviation can be performed based on the correlation between the pilot signal and the signal output from the rear end of the receive path.

[0046] Although it has been referenced Figure 2 An example of a calibration network is described, but Figure 2 The structure of the calibration network 200 shown is merely an example, and embodiments of this disclosure are not limited to a specific structure or arrangement. Furthermore, the calibration network is only an example of a circuit performing the function of controlling the characteristics of a beamforming device; it is self-evident that the calibration network described in the embodiments of this disclosure can be replaced by passive components and other circuits that perform similar functions.

[0047] As described above, since multiple RF paths are provided for beamforming, a calibration network for controlling RF characteristics is essential for beamforming devices. Below, various embodiments of this disclosure provide a method for designing an efficient beamforming device through the arrangement of RF components of the calibration network or between related RF components and filters.

[0048] Figure 3 An example of the structure of an antenna module 300 according to an embodiment of the present disclosure is shown. Antenna module 300 may refer to a module including circuitry for radiating an input RF signal into the air via antenna elements. According to an embodiment, antenna module 300 may be referred to as an antenna filter unit.

[0049] Reference Figure 3 The antenna module 300 may include an antenna element 301. Although in Figure 3An antenna element structure according to one antenna element has been exemplarily described, but the antenna module 300 can include a plurality of antenna elements. Each antenna element can be disposed on the antenna PCB 303. The antenna PCB 303, the metal plate 305, and the calibration network PCB 307 can be sequentially stacked and disposed. According to an embodiment, the calibration network PCB 307 can include a circuit (e.g., the calibration network 200) for compensating for a deviation of each RF path. The metal plate 305 can be disposed between the antenna PCB 303 and the calibration network PCB 307 to prevent the antenna PCB 303 or the calibration network PCB 307 from being bent due to external or internal factors.

[0050] The antenna module 300 can include a connection unit 311 for electrical connection between the antenna PCB 303 and the calibration network PCB 307. Although a pin-type connection unit is illustrated, it is self-evident that the connection unit can be replaced with an element performing the same or similar function. In addition, the rivet 313 can be arranged by three layers for connecting the antenna PCB 303, the metal plate 305, and the calibration network PCB 307. Figure 3

[0051] The filter 320 and the power amplifier 330 for each RF path can be disposed on the calibration network PCB 307. According to an embodiment, the filter 320 can be mounted on the calibration network PCB 307 by using a surface mount technology (SMT). However, there is a risk of cracking due to a large area and heterogeneity.

[0052] Hereinafter, in the disclosure, a method of disposing a relatively small PCB between a filter and a filter board to prevent cracking is described. Here, for convenience of description, the PCB disposed to prevent cracking can be referred to as a sub-PCB or a buffer PCB, but can also be replaced with various terms indicating the same or similar function, for example, a combination PCB, a buffer PCB, and an overlapping PCB.

[0053] ​According to embodiments, the sub-PCB that is a buffer can include elements for processing RF signals (hereinafter, RF elements). As the number of antenna elements increases, the number of RF components for processing each antenna element also increases. Installing the RF elements on one surface of the filter board increases the PCB area, while also increasing the distance between the elements. When transmitting a signal, if the length of the transmission line increases, the impedance also increases, and the increased impedance affects return loss. Accordingly, the more RF elements are provided on one filter board, the greater the loss. Accordingly, according to various embodiments of the disclosure, the RF elements are included in the sub-PCB of the filter module so that the RF elements can be close to other signal processing elements (e.g., antenna elements, filters, feed lines, RF processing circuits, etc.). When the area of the filter board is reduced, the signal processing loss of the RF elements in the antenna module is reduced, and the performance degradation (e.g., change in characteristic impedance, or insertion loss due to power feeding) can be minimized. Accordingly, according to various embodiments of the disclosure, the sub-PCB can not only provide a buffering function, but also minimize loss degradation through circuit arrangement, thereby improving processing efficiency. Hereinafter, as an example of the RF components, a harmonic cancellation circuit (e.g., an LPF), a coupler, or a connector is described, but embodiments of the disclosure are not limited thereto. Any element included in an RF signal processing path to an antenna element can be included in the sub-PCB of the disclosure.

[0054] Figure 4 An example of a filter module 400 according to embodiments of the disclosure is illustrated. In the disclosure, the filter module 400 can refer to a structure in which an RF filter 410 is coupled to a buffer PCB 420.

[0055] Referring to Figure 4 The filter module 400 can include an RF filter 410. The RF filter 410 can include a plurality of resonator regions. For example, one filter block of the RF filter 410 can include six resonator regions. The resonator regions can include a first resonator region 411, a second resonator region 412, a third resonator region 413, a fourth resonator region 414, a fifth resonator region 415, and a sixth resonator region 416. Each resonator region can correspond to a cavity formed in the filter block. According to embodiments, the RF filter 410 can be a ceramic waveguide filter. The filter block can be made of a ceramic material. A dielectric can be included in the filter block. Further, according to embodiments, a conductive metal layer can be formed on a surface of the filter block. The conductive metal layer can be partially removed for a specific function. For example, the conductive metal layer can be partially removed from the input / output resonator region for plating and circuit breaking around the boundary surface of the input / output trench, and the conductive metal layer of a specific portion can be removed for tuning of the frequency and the amount of coupling.

[0056] The filter module 400 can include a buffer PCB 420. Below, various embodiments of the disclosure propose a filter module in which a passive circuit is inserted into the buffer PCB to reduce the size of the filter board. When the filter included in the filter module is a ceramic filter, the filter module can be referred to as a ceramic waveguide filter module structure. As described above, due to the difference in the coefficient of terminal expansion (CTE) between the filter (for example, the filter 320 in Figure 3 , and the filter board (for example, the calibration network PCB 307 in Figure 3 , cracking can occur. The buffer PCB 420 can be used to prevent cracking.

[0057] According to various embodiments, at least one passive circuit can be included in the buffer PCB. According to an embodiment, the at least one passive circuit can include an LPF. According to an embodiment, the at least one passive circuit can include a coupler. According to an embodiment, the at least one passive circuit can include a connector. For example, the buffer PCB can be integrated with a pin configuration. Such an integrated structure can be referred to as a ceramic filter module. The multi-layer structure of the buffer PCB according to each passive circuit will be described with reference to Figures 5a to 5d .

[0058] In the disclosure, the type of filter is described taking a ceramic waveguide filter as an example, but embodiments of the disclosure are not limited thereto. Even if the filter is not a ceramic filter, any structure in which a PCB is added to the filter in order to prevent cracking (for example, a miniaturized filter using a dielectric in a resonator) can be understood as the content of the disclosure. When a dielectric is used in a resonator, the size of the resonator is reduced due to the dielectric, and the strength per unit volume is increased. Since the resonator is filled with a dielectric, the overall size of the filter is reduced compared to the case where the resonator is filled only with air without using a dielectric, and thus SMT can be feasible. Unlike a metal filter, a ceramic filter is difficult to be physically fixed (for example, screwed) to the corresponding place, and thus SMT coupling is required. However, cracking easily occurs due to the difference in CTE. Therefore, a buffer PCB having a size significantly smaller than the filter board (or calibration PCB) is used to prevent cracking. That is, a buffer PCB is used to prevent cracking, and passive circuits used in the filter board are implemented in the buffer PCB, so that the area of the filter board can be reduced. Below, examples of passive circuits implemented in the buffer PCB are shown. Figures 5a to 5d

[0059] Figures 5a to 5d Examples of passive circuits provided on the buffer PCB of the filter module according to embodiments of the disclosure are shown. Here, Figure 4 ​The buffer PCB 420 in the middle is illustrated as a buffer PCB.

[0060] Referring to Figure 5a , according to an embodiment, the LPF 513 can be disposed on the buffer PCB 510. The LPF 513 can include a passive circuit. For example, the LPF 513 can include an inductor and a capacitor. The LPF 513 can be disposed on the buffer PCB 510 in order to remove a harmonic component caused in a predetermined range due to a high dielectric constant of a ceramic waveguide filter.

[0061] The LPF is not disposed on a filter board for disposing a plurality of filters, but is disposed on a layer of a buffer PCB that is a buffer between the filter board and the RF filter, so that the area of the filter board can be reduced. According to an embodiment, the filter board can include Figure 3 The calibration network PCB 307 in the middle. According to an embodiment, the filter board can include an AFU PCB. In addition, according to an embodiment, the filter board can include an amplifier (AMP) board. This is because the buffer PCB of the filter module of the present disclosure can also be connected to the AMP board.

[0062] Referring to Figure 5b , according to an embodiment, the LPF 533 and the coupler 536 can be disposed on the buffer PCB 530. That is, unlike the buffer PCB 510, not only the LPF but also the coupler 536 can be additionally disposed. Like the LPF 513, the LPF 533 can be a passive circuit for removing a harmonic component. The coupler (or combiner) 536 can include a passive circuit for beamforming calibration of each RF path. The coupler 536 can be disposed between the input port and the output port. For example, the passive circuit can include a transmission line and a passive element. The coupler is not disposed on a filter board for disposing a plurality of filters, like the calibration network PCB 307 or the AFU PCB in Figure 3 , but is disposed on a layer of a buffer PCB that is a buffer between the filter board and the RF filter, so that the area of the filter board can be reduced. Although both the LPF and the coupler have been described as being disposed on the buffer PCB 530 in Figure 5b , a structure in which the LPF is mounted on the filter board and only the coupler is disposed on the buffer PCB can also be understood as an embodiment of the present disclosure.

[0063] Referring to Figure 5cAccording to an embodiment, the LPF 553, the coupler 556, and the connector 559 can be disposed on the buffer PCB 550. That is, unlike the buffer PCB 510 and the buffer PCB 530, the connector 559, and the LPF and the coupler can be additionally disposed. Like the LPF 513 and the LPF 533, the LPF 553 can be a passive circuit for removing harmonic components. The coupler (or combiner) 556 can include a passive circuit for beamforming calibration of each RF path. The connector 559 can include an RF interface. The connector 559 can include one or more RF feed lines for providing electrical connection of the RF filter through the RF interface. The connector is not disposed on the filter board for arranging a plurality of filters, like the calibration network PCB 307 or the AFU PCB in Figure 3 , but is disposed on a layer of the buffer PCB that is a buffer between the filter board and the RF filter, so that the area of the filter board can be reduced. According to an embodiment, the buffer PCB can further include an additional structure for connecting the buffer PCB to the filter board or the antenna board. The additional structure can include the connector 559.

[0064] Referring to Figure 5d , according to an embodiment, the LPF 573, the coupler 576, and the connector 559 can be disposed on the buffer PCB 570. Figures 5a to 5c A structure in which passive circuits are disposed on two layers of a buffer PCB is illustrated, but embodiments of the disclosure are not limited thereto. The structure can be disposed on different layers of the respective passive circuits. According to an embodiment, the buffer PCB 570 can include a substrate 580 including three layers. The LPF 573 can be mounted on the first layer of the buffer PCB 570. The coupler 576 can be mounted on the second layer of the buffer PCB 570. The connector 579 can be mounted on the third layer of the buffer PCB 570. Although not illustrated in Figure 5d , it goes without saying that the arrangement of each layer of the buffer PCB can change, or an additional layer of another passive circuit can be included in the buffer PCB.

[0065] Figure 6 An effect of reducing the area of a filter board due to a filter module according to an embodiment of the disclosure is illustrated. Filters (or filter modules) for each RF path are disposed on a filter board. As the RF components disposed on the surface of the filter board increase, the area of the filter board required also increases. Hereinafter, in Figure 6A filter board of a 32T32R (32 transmission paths and 32 reception paths) antenna module is described as an example. Specifically, a structural comparison is explained depending on whether a passive circuit (e.g., an LPF, a coupler, or a connector) for processing an RF signal is disposed on a filter board or a buffer PCB.

[0066] Referring to Figure 6 According to the existing structure 610, a ceramic waveguide filter, a buffer PCB, and a passive circuit for processing an RF signal can be disposed on one surface of a filter board 611. For example, the size of the filter board 611 can be 788 mm x 316 mm. Specifically, a structure 613 for each RF path of the filter board 611 can include a ceramic waveguide filter 613a, a buffer PCB 613b, an LPF 613c, and a coupler 613d, which are arranged on a single surface.

[0067] According to the proposed structure 660, a ceramic waveguide filter and a buffer PCB are disposed on one surface of a filter board 661, and at least one passive circuit for processing an RF signal can be disposed on the buffer PCB. For example, the size of the filter board 661 can be 530 mm x 316 mm. The area of the filter board 661 can be reduced by about 35% for a single antenna module of 32T32R. According to an embodiment, when two antenna modules 663a and 663b are alternately arranged in a "C" shape, the area of the filter board 663 can be reduced by about 50%. Specifically, a structure 665 for each RF path of the filter board 661 or the filter board 663 can include a ceramic waveguide filter 665a, an LPF 665b, a coupler 665c, and a connector 665d, which are arranged in a stacked form. In this case, the LPF 665b, the coupler 665c, and the connector 665d can be implemented in a layer of the buffer PCB between the ceramic waveguide filter 665a and the filter board. Each RF component can be disposed on the filter board, i.e., a calibration network PCB. Since the main passive circuit is implemented as stacked on the ceramic waveguide filter module, the area of the filter board can be reduced. The reduction in the area of the filter board provides a reduction in the length of an RF signal processing path to an antenna element. When the length of the RF signal processing path is reduced, return loss due to impedance or feed loss due to circuit insertion is reduced. Accordingly, the reduction in the area of the filter board can provide a gain enhancement of RF signal processing.

[0068] Figures 7a to 7c An example of a connection structure of a filter module and a filter board according to an embodiment of the disclosure is illustrated. A component for the connection structure can be referred to as a connector. The connector can include an RF interface for processing an RF signal. According to an embodiment, the filter board can include Figure 3The filter board 730 can include a calibration network PCB 307. According to another embodiment, the filter board can include a PCB having one surface on which a plurality of filters are disposed (e.g., an AFU PCB). At least some of the passive circuits for calibration can be implemented on the buffer PCB, while at least other passive circuits can be disposed at a separate location of the antenna module. The structure in which the connectors are added is configured and the input / output ports of the structure are configured, so that deterioration of characteristics (e.g., return loss or phase) due to SMT tolerance is low and an additional tuning process is not required. For this reason, the cost of mass production can be reduced.

[0069] Referring to Figure 7a , the filter module can include an RF filter 710, a buffer PCB 720, and a filter board 730. According to an embodiment, the RF filter 710 can include a ceramic waveguide filter. The buffer PCB 720 can be disposed between the RF filter 710 and the filter board 730. At this time, the buffer PCB 720 can include a structure for connecting the buffer PCB 720 to the filter board 730. The buffer PCB 720 can include a connection structure for the input port 711. According to an embodiment, the connection structure can include a direct matching connection unit for the input port 711. The direct matching connection unit can include a pin-socket structure. For example, the buffer PCB 720 can include a pin structure. The filter board 730 as a counterpart can include a socket structure. Accordingly, the structure of the buffer PCB 720 can be arranged for fastening the filter module 720 to the filter board 730. In order to effectively design in terms of the size and cost of the connection unit, the direct matching connection unit can be included. The buffer PCB 720 can include a connection structure for the output port 713. According to an embodiment, the connection structure can include a blind matching connection unit for the output port 713. In order to have a wider allowable tolerance when assembling each filter and RF component, the blind matching connection unit can be used.

[0070] Referring to Figure 7b , the filter module can include an RF filter 710, a buffer PCB 720, and a filter board 730. According to an embodiment, the RF filter 710 can include a ceramic waveguide filter. The buffer PCB 720 can be disposed between the RF filter 710 and the filter board 730. The buffer PCB 720 can include a structure for connecting the buffer PCB 720 to the filter board 730. At this time, a wider allowable tolerance than the connection unit shown in FIG. 7 can be used for the input and output ports. Figure 7a The filter module can include a first blind matching connection unit 745 and a second blind matching connection unit 746 for the input port and the output port, respectively.

[0071] Referring to Figure 7c , the filter module can include an RF filter 710, a buffer PCB 720, and a filter board 730. According to an embodiment, the RF filter 710 can include a ceramic waveguide filter. The buffer PCB 720 can be disposed between the RF filter 710 and the filter board 730. The buffer PCB 720 can include a structure for connecting the buffer PCB 720 to the filter board 730. In this case, a direct matching connection unit can be used to make the filter module smaller than the filter module shown in FIGS. 1A to 1C. Figure 7a or Figure 7b The filter module can include a first direct matching connection unit 771 and a second direct matching connection unit 772 for input and output ports, respectively.

[0072] Figure 8 An example of a through-hole port of a filter module according to an embodiment of the disclosure is illustrated. Figure 4 The filter module 400 in FIG. 1D is illustrated as a filter module.

[0073] Referring to Figure 8 , the filter module 400 can include an RF filter 410 and a buffer PCB 420. According to an embodiment, the buffer PCB 420 can include a structure 831 for connecting the buffer PCB 420 to a filter board. This structure 831 illustrates a form in which one layer of the buffer PCB V is removed. According to an embodiment, the buffer PCB 420 can include a passive circuit 840. The passive circuit 840 can include at least one of an LPF, a coupler, or a connector. According to an embodiment, the buffer PCB 420 can include a through-hole port. The through-hole port refers to an input port or an output port formed in the form of a through-hole. Since this port is configured to be integrated in the buffer PCB 420, the number of components constituting the filter module is also reduced, and thus simplification of the component process can be achieved.

[0074] Figure 9 Functional elements of an electronic device including a filter module according to various embodiments of the disclosure are illustrated. The electronic device 910 can be one of the base station 110 or the terminal 120 in FIG. 1A. Figure 1 a According to an embodiment, the electronic device 910 can be an MMU. In addition to the antenna structure itself described through Figures 1 a to 8 , an electronic device including the antenna structure is included in embodiments of the disclosure.

[0075] Referring to Figure 9 , exemplary functional elements of the electronic device 910 are illustrated. The electronic device 910 can include an antenna unit 911, a filter unit 912, a radio frequency (RF) processing unit 913, and a controller 914.

[0076] The antenna unit 911 can include a plurality of antennas. The antenna performs a function of transmitting and receiving a signal through a wireless channel. The antenna can include a conductor formed on a substrate (e.g., a PCB) or a radiator formed as a conductive pattern. The antenna can radiate an up-converted signal on a wireless channel or acquire a signal radiated by another device. Each antenna can be referred to as an antenna element or an antenna device. In some embodiments, the antenna unit 911 can include an antenna array in which a plurality of antenna elements are arranged. The antenna unit 911 can be electrically connected to the filter unit 912 through an RF signal line. The antenna unit 911 can be mounted on a PCB including a plurality of antenna elements. The PCB can include a plurality of RF signal lines connecting each antenna element to a filter of the filter unit 912. The RF signal line can be referred to as a feed network. The antenna unit 911 can provide a reception signal to the filter unit 912, or can radiate a signal provided from the filter unit 912 into the air.

[0077] The filter unit 912 can perform filtering to transmit a signal of a desired frequency. The filter unit 912 can form a resonance to perform a function of selectively recognizing a frequency. According to various embodiments, the filter unit 912 can include a filter module to which a filter and a buffer PCB according to various embodiments of the disclosure are coupled. The filter unit 912 can include a filter module including a cavity filter (e.g., a filter having a dielectric included in a ceramic cavity) and a buffer PCB. According to an embodiment, the filter module can include an LPF circuit for removing a harmonic component generated in a relatively low domain due to a high dielectric constant. In addition, according to an embodiment, the filter module can include a passive circuit for a beamforming process. For example, the passive circuit can include a coupler (or a combiner) for beamforming calibration. In addition, according to an embodiment, the filter module can include a connector for an RF interface between an antenna PCB and a filter board.

[0078] The filter unit 912 can include at least one of a band pass filter, a low pass filter, a high pass filter, or a band reject filter. That is, the filter unit 912 can include an RF circuit for obtaining a frequency band signal for transmission or a frequency band signal for reception. The filter unit 912 according to various embodiments can electrically connect the antenna unit 911 and the RF processing unit 913.

[0079] The RF processing unit 913 can include a plurality of RF paths. Each RF path can be a unit of a path through which a signal received through an antenna or a signal radiated through an antenna passes. At least one RF path can be referred to as an RF chain. The RF chain can include a plurality of RF elements. The RF elements can include an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. For example, the RF processing unit 913 can include an up-converter for up-converting a digital transmission signal of a baseband to a transmission frequency and a digital-to-analog converter (DAC) for converting the up-converted digital transmission signal to an analog RF transmission signal. The up-converter and the DAC constitute a part of a transmission path. The transmission path can further include a power amplifier (PA) or a coupler (or a combiner). Also, for example, the RF processing unit 913 can include an analog-to-digital converter (ADC) for converting an analog RF reception signal to a digital reception signal, and a down-converter for converting the digital reception signal to a baseband digital reception signal. The ADC and the down-converter constitute a part of a reception path. The reception path can further include a low noise amplifier (LNA) or a coupler (or a divider). The RF components of the RF processing unit can be implemented on a PCB. The base station 910 can include a structure stacked in the order of the antenna unit 911-filter unit 912-RF processing unit 913. The antennas and the RF components of the RF processing unit can be implemented on a PCB, and the filters can be repeatedly fastened between the PCBs to form a plurality of layers. According to an embodiment, some passive circuit elements of the RF processing unit can be mounted on one layer of the buffer PCB of the filter unit 912.

[0080] The controller 914 can control the overall operation of the electronic device 910. The control unit 914 can include various modules for performing communication. The controller 914 can include at least one processor such as a modem. The controller 914 can include a module for digital signal processing. For example, the controller 914 can include a modem. When transmitting data, the controller 914 generates complex symbols by encoding and modulating a transmitted bit stream. Also, for example, when receiving data, the controller 914 recovers a received bit stream by demodulating and decoding a baseband signal. The controller 914 can perform the functions of a protocol stack required by a communication standard.

[0081] In Figure 9 , the functional elements of the electronic device 910, which is a device that can use the antenna structure of the present disclosure, have been described. However, Figure 9 the examples shown in Figures 1 a to 8 are only example elements of the RF filter structure according to various embodiments of the present disclosure described with reference to Figure 9The components of the device shown are illustrated. Accordingly, antenna modules including antenna structures, communication devices with different configurations, and the antenna structures themselves can also be understood as embodiments of this disclosure.

[0082] According to an embodiment, the sub-PCB serving as a buffer may include RF components (e.g., elements that can be placed in an RF processing chain) included in the RF processing unit. This RF component may be associated with an antenna element. When transmitting a signal, if the length of the transmission line increases, the impedance increases, which affects the return loss. Furthermore, as... Figure 3 As shown, because the antenna module is arranged in a stacked structure, performance degradation can occur due to the length of the feed lines as they pass through the layers. To minimize performance degradation (e.g., variations in characteristic impedance or insertion loss due to power supply), RF components closely related to the antenna elements need to be positioned closer to them. For example, in an antenna module with a stacked structure, performance can be enhanced by placing the RF components on a sub-PCB of the filter. The sub-PCB can increase antenna gain while minimizing loss degradation by providing buffering functionality.

[0083] Filter modules according to various embodiments of the present disclosure may include a buffer PCB and an RF filter. The filter module may be mounted on a filter board. According to embodiments, the filter board may include a calibration network PCB. Additionally, according to embodiments, the filter board may include an antenna filter unit (AFU) PCB. The buffer PCB may include at least one of couplers, frequency dividers, connectors, and LPFs conventionally implemented on filter boards. According to embodiments, the buffer PCB may have a multilayer structure. At least one passive circuit may be implemented in each layer of the buffer PCB, thereby reducing the size of the filter board. Furthermore, the buffer PCB is positioned between the filter board and the RF filter, thereby preventing SMT performance degradation. By implementing the buffer PCB, cracking during SMT using ceramic filters can be prevented, and the area of ​​the filter board can be reduced (approximately 50%). In other words, according to various embodiments of the present disclosure, the filter module may include a structure in which the size of the main PCB can be reduced by using a buffer PCB with a stacked structure. See reference... Figure 6 As mentioned above, the unit cost can be reduced by decreasing the area of ​​the PCB. Due to the arrangement of the buffer PCB, the performance degradation caused by phase component changes or return loss is relatively low when assembling filter modules and filter boards. Furthermore, a separate tuning process is not required when manufacturing the filter board, thus reducing the unit cost.

[0084] According to an embodiment of the disclosure, an antenna filter module can include a filter configured to filter a radio frequency (RF) signal, and a sub-printed circuit board (PCB), wherein the sub-PCB includes a passive circuit configured to process the RF signal, and the sub-PCB is coupled to the filter so as to operate as a buffer when the filter is coupled to a filter board.

[0085] According to an embodiment of the disclosure, in the filter module, the filter can be a ceramic waveguide filter.

[0086] According to an embodiment of the disclosure, the passive circuit can include a low pass filter (LPF).

[0087] According to an embodiment of the disclosure, the passive circuit can include a coupler for beamforming of the RF signal.

[0088] According to an embodiment of the disclosure, the passive circuit can include a connector for an RF interface.

[0089] According to an embodiment of the disclosure, the sub-PCB can be formed to have a plurality of layers, and the passive circuit can include at least one of a low pass filter (LPF), a connector, and a coupler.

[0090] According to an embodiment of the disclosure, the LPF can be mounted on a first layer of the plurality of layers, and the connector can be mounted on a second layer of the plurality of layers.

[0091] According to an embodiment of the disclosure, the sub-PCB can include a structure for a port formed as a through hole.

[0092] According to an embodiment of the disclosure, the sub-PCB can include a groove structure for directly matching a connection unit or a blind matching connection unit.

[0093] According to an embodiment of the disclosure, the filter board can include a calibration network PCB for beamforming processing of the RF signal.

[0094] According to an embodiment of the disclosure, a massive multiple-input multiple-output (massive MIMO) unit (MMU) apparatus in a wireless communication system can include at least one processor configured to process a signal, a plurality of radio frequency (RF) filter modules configured to filter the signal, and an antenna array configured to radiate the signal, wherein an RF filter module of the plurality of RF filter modules includes a filter configured to filter an RF signal, and a sub-printed circuit board (PCB) coupled to the filter, the sub-PCB including a passive circuit configured to process the RF signal, and the sub-PCB being coupled to the filter so as to operate as a buffer when the filter is coupled to a filter board.

[0095] According to embodiments of this disclosure, the filter may be a ceramic waveguide filter.

[0096] According to embodiments of this disclosure, passive circuitry may include a low-pass filter (LPF).

[0097] According to embodiments of this disclosure, the passive circuit may include a coupler for beamforming RF signals.

[0098] According to embodiments of this disclosure, passive circuitry may include connectors for RF interfaces.

[0099] According to embodiments of this disclosure, the subPCB can be formed in multiple layers, and the passive circuitry can include at least one of a low-pass filter (LPF), a connector, and a coupler.

[0100] According to embodiments of this disclosure, the LPF can be mounted on a first layer of a plurality of layers, while the connector can be mounted on a second layer of a plurality of layers.

[0101] According to embodiments of this disclosure, a subPCB may include a structure with ports formed as through holes.

[0102] According to embodiments of this disclosure, the subPCB may include a trench structure for direct mating connection units or blind mating connection units.

[0103] According to embodiments of this disclosure, the filter board may include a calibration network PCB for beamforming processing of RF signals.

[0104] The methods described in the claims or specification of this disclosure can be implemented in hardware, software, or a combination of hardware and software.

[0105] When the method is implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors within an electronic device. The at least one program may include instructions that cause the electronic device to perform the method according to the appended claims and / or various embodiments of the present disclosure disclosed herein.

[0106] The program (software module or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magneto-optical disk storage devices, optical disk (CD-ROM), digital versatile optical disk (DVD), or other types of optical storage devices or magnetic tape. Furthermore, any combination of some or all of these can constitute the memory storing the program. In addition, multiple such memories may be included in an electronic device.

[0107] Further, programs can be stored in the attachable storage device which can access the electronic device through a communication network (e.g., the Internet, an intranet, a local area network (LAN), a wide area network (WAN), and a storage area network (SAN), or a combination thereof). Such a storage device can access the electronic device through an external port. Further, a separate storage device on a communication network can access a portable electronic device.

[0108] In the detailed embodiments of the disclosure described above, one element included in the disclosure is expressed in singular or plural according to the proposed detailed embodiments. However, for the convenience of description, the singular form or the plural form is appropriately selected according to the proposed case, and the disclosure is not limited by the element expressed in singular or plural. Therefore, the element expressed in plural can also include a single element, or the element expressed in singular can also include a plurality of elements.

[0109] Although specific embodiments have been described in the detailed description of the disclosure, various modifications and changes can be made thereto without departing from the scope of the disclosure. Accordingly, the scope of the disclosure should not be defined by the embodiments, but by the appended claims and their equivalents.

Claims

1. An antenna module (400), the antenna module (400) comprising: At least one antenna array, the at least one antenna array comprising a plurality of antenna elements; At least one radio frequency (RF) chip; The board includes multiple RF components for multiple RF paths; Multiple ceramic waveguide filters (410), each of the multiple ceramic waveguide filters being disposed in an RF path of the multiple RF paths; Multiple sub-boards (420) are used as buffers, each of the multiple sub-boards (420) being coupled to a corresponding ceramic waveguide filter (410). and Each of the plurality of sub-boards (420) includes an input port (711) and an output port (713) formed by through-holes for the corresponding ceramic waveguide filter, and a low-pass filter (513, 573) for filtering the RF signal applied to the input port, wherein the low-pass filter is an LPF. The plurality of sub-boards (420) are disposed between the plurality of ceramic waveguide filters (410) and the board.

2. The antenna module according to claim 1, in, The board includes at least one RF component for beamforming calibration; and Each of the plurality of sub-boards (420) includes a coupler for the beamforming calibration.

3. The antenna module (400) according to claim 1, wherein, Each of the plurality of subboards (420) includes connectors (559, 579) for an RF interface.

4. The antenna module (400) according to claim 1. in, Each of the plurality of sub-boards (420) comprises a plurality of layers.

5. The antenna module (400) according to claim 4. in, The LPF (573) is mounted on the first of the plurality of layers. The coupler (536) is mounted on the second of the plurality of layers, and The connector (579) is mounted on the third layer of the plurality of layers.

6. The antenna module (400) according to claim 1, wherein, Each of the plurality of sub-boards includes a groove structure for direct mating connection units or blind mating connection units.

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