RF Level Controller

Abstract

To provide an RF level controller housed in a device that maximizes heat dissipation effect so that the temperature does not exceed 70 to 80 degrees while maintaining specified waterproof performance. [Solution] The RF level controller 100 comprises a box-shaped container 1 that houses a printed circuit board on which multiple level adjustment circuits for RF signals are formed, a lid with a heat sink 7 formed on its surface that seals the box-shaped container, and a switch module 3 that is screwed onto the outside of one of the short side surfaces 16 of the box-shaped container and turns each of the level adjustment circuits on and off, and the lid is screwed onto the box-shaped container with a sealant placed around the periphery of the opening of the box-shaped container in between.

Description

[Technical Field]

[0001] This invention relates to an RF level controller with waterproof and heat dissipation functions that can be installed in base stations such as 5G and adjust the level of input and output RF signals. [Background technology]

[0002] The fifth-generation mobile communication system (5G) is allocated 3.7GHz, 4.5GHz, and 28GHz, allowing the use of higher frequency bands than 4G. This means that it will be possible to achieve higher speeds, larger capacity, lower latency, and multiple simultaneous connections compared to previous systems. For this reason, autonomous driving, remote-controlled robots, remote medical care, smart cities, factory automation, etc. Various uses are being considered, and various types of base stations are being considered for access by a variety of terminal devices. As frequencies increase, radio waves tend to travel more directly and propagation loss increases, resulting in a smaller coverage area, necessitating the installation of multiple base stations or limiting service to local areas. Furthermore, the communication equipment at the base station side must be installed outdoors and, due to installation environment constraints, it must be as compact as possible. Furthermore, as frequencies increase, high-output circuits are implemented, which can cause the equipment to heat up, making it necessary to prevent component degradation and changes in characteristics. However, because the equipment is installed outdoors, it must also be protected from moisture and water intrusion, so it must be both heat-dissipating and waterproof.

[0003] CATV amplifiers need to be electromagnetically shielded to suppress noise from various signal sources. To address this, the amplifier and power supply units are housed in separate chambers separated by aluminum alloy walls. However, the heat generated by these components builds up inside the chassis, causing the components to deteriorate or their characteristics to change. To prevent this, a CATV amplifier has been proposed that has a heat dissipation section on the back of the chassis with numerous fins extending out and forming numerous recesses (see Patent Document 1). Furthermore, in mobile stations used for TV broadcasting, etc., there is a risk that the electrical components of the relay device may be damaged by high temperatures. To solve this problem, a protective case for the relay device has been proposed, which has a fan and numerous fins attached to the side wall of the case, and a heat dissipation tube that forms a continuous S-shape attached to the fins, and which circulates water through the heat dissipation tube with a pump to dissipate heat from the relay device (see Patent Document 2). Furthermore, MIMO antennas require high output power to expand coverage, and in order to improve heat dissipation performance while reducing size, a heat sink structure has been proposed in which a cover plate that receives heat from the heat-generating elements on the printed circuit board divides the space into an accommodating space for the printed circuit board and a refrigerant chamber filled with refrigerant, and multiple refrigerant condensation groups are formed in which the gas-phase refrigerant that has exchanged heat with the cover plate flows and condenses (see Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-14285 [Patent Document 2] Patent No. 7003351 [Patent Document 3] Special Publication No. 2025-524063 Summary of the Invention [Problem to be solved by the invention]

[0005] Wireless communication equipment installed at base stations must be housed in as small a container as possible to minimize component deterioration and changes in characteristics in the restricted outdoor environment. Therefore, the object is to provide an RF level controller housed in a device that maximizes heat dissipation so that the temperature does not exceed 70 to 80 degrees while maintaining the specified dustproof and waterproof performance. [Means for solving the problem]

[0006] The RF level controller of the present invention comprises a box-shaped container that houses a printed circuit board on which multiple level adjustment circuits for input and output RF signals are formed and has a heat sink formed on its bottom surface, a lid that seals the box-shaped container, and a switch module that is screwed onto the outside of one short side surface of the box-shaped container and turns each of the level adjustment circuits on and off, and is characterized in that the lid is screwed onto the box-shaped container with a sealant placed around the periphery of the opening of the box-shaped container in between. In this way, a heat sink is formed on the entire bottom surface of the container that houses the heat source, maximizing the heat dissipation effect. In addition, a sealant is sandwiched between the opening of the container and the lid to tightly seal the two together, and the container is fastened with screws at multiple points, meeting the specified dustproof and waterproof standards (IP65, IP67). Furthermore, it is preferable that contact portions for connecting the switch modules to the respective level adjustment circuits are formed on the outside of the short side surfaces, and that each of the contact portions is sealed to the short side surfaces, and that input / output terminals for the RF signals are formed on the outside of the side surface opposite to the short side surface on which the switch modules are screwed, and that the input / output terminals are sealed with a sealing material. In this way, by sealing the side of the container where the contacts of the level adjustment circuit are formed and the side of the container where the input / output terminals of the RF signal are formed with a sealant, rainwater and other water will not seep into the container containing the printed circuit board.

[0007] The integrated level controller of the present invention comprises N box-shaped containers each having a heat sink formed on its bottom surface and housing a printed circuit board on which a plurality of level adjustment circuits for input and output RF signals are formed, N lids for sealing each of the box-shaped containers, N switch modules for turning each of the level adjustment circuits on and off, and a connecting plate for connecting the N box-shaped containers, wherein each of the N switch modules is screwed onto the outside of one short side surface of each of the N box-shaped containers, and each of the N lids is screwed onto each of the N box-shaped containers via a sealant arranged on the periphery of the opening of each of the N box-shaped containers, and the N box-shaped containers with the N switch modules screwed in and the N lids screwed onto them are lined up side by side, and all of the N switch modules are covered with the connecting plate and screwed onto each of the box-shaped containers, thereby connecting all of the N box-shaped containers. [Effects of the Invention]

[0008] According to the RF level controller and combined RF level controller of the present invention, high-power components are housed in a box-shaped container with a heat sink formed therein, thereby achieving sufficient heat dissipation effect, and since the box-shaped container is tightly sealed, it can provide the specified waterproof and dustproof functions even when installed outdoors. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view showing an embodiment of the RF level controller of this embodiment. [Figure 2] FIG. 2 is a side view showing an embodiment of the RF level controller of this embodiment. [Figure 3] FIG. 3 is a bottom view showing the RF level controller according to the present embodiment. [Figure 4] FIG. 4 is a front view showing the RF level controller according to the present embodiment. [Figure 5] FIG. 5 is a rear view showing the RF level controller according to the present embodiment. [Figure 6] FIG. 6 is a view showing the inside of the box-shaped container of this embodiment. [Figure 7] FIG. 7 is a diagram showing a side view of the box-shaped container to which the switch module is attached. [Figure 8] FIG. 8 is a front view showing an embodiment of the combined RF level controller of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an RF level controller according to the present invention will be described below with reference to the accompanying drawings. 1 to 5 are external views showing the RF level controller of this embodiment, with FIG. 1 being a plan view, FIG. 2 being a side view, FIG. 3 being a bottom view, FIG. 4 being a front view, and FIG. 5 being a rear view. As shown in Figures 1 to 5, the RF level controller 100 of this embodiment is composed of a box-shaped container 1 that houses a printed circuit board on which multiple level adjustment circuits for inputting and outputting RF signals are formed and has a heat sink 7 formed on its bottom surface, a lid 2 that seals the box-shaped container 1, a switch module 3 that turns each of the level adjustment circuits ON / OFF, and an RF signal input / output terminal 5. The box-shaped container 1 and the lid 2 are made of an aluminum alloy that has electromagnetic shielding properties. A box-shaped container 1 having a heat sink 7 formed on the bottom surface is sealed with a lid 2 via a sealing material and is fastened with screws at multiple points. A contact portion (not shown) connected to a level adjustment circuit is formed on the outside of one of the short side surfaces 16. The switch module 3 is firmly screwed to the box-shaped container 1 with a fixing plate 4 so that the contact portion is in close contact with the fixing plate 4. The switch module 3 can be screwed to the fixing plate 4 after being covered with a waterproof cover (not shown). An input / output terminal 5 for RF signals is attached to a short side surface 16 opposite to the side where the switch module 3 is screwed, and is sealed with a sealing material 6 . Therefore, the box-shaped container 1 and the input / output terminals 5 satisfy IP65 or IP67 and have dustproof and waterproof functions, and the switch module 3 can also have dustproof and waterproof functions.

[0011] 2 and 3, a large number of fins 8 extend in the left-right direction on the bottom surface 1a of the box-shaped container to form a heat sink 7. Air flows in recesses 9 formed between the fins 8, allowing the box-shaped container bottom surface 1a to release heat to the outside. Meanwhile, air heated by a heat source (level adjustment circuit, etc.) circulates inside the box-shaped container 1 and is cooled by coming into contact with the bottom surface 1a of the box-shaped container, thereby preventing the temperature inside from rising. Incidentally, when the ambient temperature is 25 degrees, the surface temperature of the box-shaped container 1 can be maintained at about 70 to 80 degrees two hours after the RF level controller 100 is started.

[0012] The switch module 3 shown in Figure 4 is a 5G DPDT module connected to 12 double-pole, double-throw switches, six for transmission and six for reception. By turning on / off each of the 12 variable attenuators 21 in the level adjustment circuit 20 formed on the printed circuit board 10 housed in the box-shaped container 1, the signal levels for transmission and reception can be varied from 0 dB to 41 dB. However, the numerical values ​​shown here are merely an example and are not necessarily limited to the numerical values ​​shown here. The switch module 3 does not need to be limited to those shown here, and it may also be configured separately for transmission and reception.

[0013] The input / output terminal 5 shown in FIG. 5 is a connector for connecting to a base station or a repeater, and may be an N-type coaxial connector or a 4.3 / 10-type connector, but is not limited to these. The input / output terminals 5 are attached to the short side surfaces 16 of the box-shaped container 1 via a seal material 6, ensuring dustproof and waterproof properties.

[0014] FIG. 6 is a view showing the inside of the box-shaped container of this embodiment. As shown in Figure 6, multiple screw holes 12 for screwing the lid 2 are provided around the opening periphery 11 of the box-shaped container 1, and a sealing material 6 for sealing the box-shaped container 1 is arranged all over the opening periphery 11. Furthermore, a contact portion (not shown) with the switch module 3 fixed by the fixing plate 4 is attached in a sealed state to one short side surface 16 of the box-shaped container 1, and input / output terminals 5 are attached to the opposite short side surface 16 via a sealing material 6. Therefore, dust, water, and moisture do not penetrate into the short side surface 16 to which the switch module 3 is screwed and the short side surface 16 to which the input terminals 5 are attached. A printed circuit board 10 is housed inside the box-shaped container 1, and formed on the printed circuit board 10 are two stages of six variable attenuation circuits 21, totaling 12 circuits, which are connected to the contacts with the switch module 3. The attenuation amounts of the attenuation circuits are 1, 2, 3, 5, 10, and 20 dB, respectively, and by turning them on and off, the attenuation amount of the input / output RF signals can be varied from 0 dB to 41 dB. The six attenuation circuits in one stage are connected via a 20 dB fixed attenuator 22, and the six attenuation circuits in another stage are connected via an isolator 13, and both ends of each circuit are connected to the input / output terminal 5 via separate circulators 14. Here, both ends of the circuit are connected to separate circulators 14, but instead of the circulator 14 connected after passing through the fixed attenuator 22, it may be possible to pass through a duplexer. The fixed attenuator 22 in this embodiment is composed of a resistor and is the largest heat source, so it is placed in the center of the box-shaped container 1 separately from the variable attenuation circuit 21 to maximize the heat dissipation effect.

[0015] FIG. 7 is a diagram showing a side view of the box-shaped container to which the switch module is attached. As shown in Figure 7, a heat sink 7 is formed on the bottom surface 1a of the box-shaped container, and is sealed with a lid via a sealing material 6 placed on the periphery 11 of the opening. The lid is then firmly fastened with screws inserted into the screw holes 12. The switch module 3 is fixed to one short side surface 16 of the box-shaped container 1 with a fixing plate 4, and the input / output terminals 5 are tightly attached to the opposite short side surface 16 via a sealing material 6, so that water, moisture, and dust do not penetrate into the inside of the box-shaped container 1. In addition, air flows through the recesses 9 formed on the bottom surface 1a of the box-shaped container by the numerous fins 8 of the heat sink 7, and the hot air that comes into contact with the bottom surface 1a of the box-shaped container is cooled and circulates within the box-shaped container 1, so that the temperature inside the box-shaped container 1 can be maintained below a predetermined temperature.

[0016] Figure 8 is a plan view showing an embodiment of the combined RF level controller of this embodiment. Note that the side view of the combined RF level controller is the same as Figure 2, and the bottom and back views are omitted because they are the same as four of the controllers shown in Figures 3 and 5 lined up. The combined RF level controller 200 shown in Figure 8 is substantially the same as the RF level controller 100 shown in Figures 1 to 5, with four box-shaped containers 1 lined up horizontally, but on the front side where the switch module 3 is fixed, a long combining plate 30 is screwed to each box-shaped container 1 to form the combined RF level controller 200. Here, in this embodiment, four box-shaped containers 1 of the RF level controller 100 are arranged side by side, but this does not necessarily have to be four, and may be two, six, or any other number. Also, in this embodiment, the front sides of the four box-shaped containers 1 are joined by screwing a long joining plate 30, but the rear sides may also be joined by a long fixing plate. By providing a combined RF level controller 200 configured with a plurality of box-shaped containers 1 in this way, it is possible to respond immediately to cases where it is necessary to urgently increase the number of accesses. [Industrial Applicability]

[0017] It can be used as a housing for communication equipment in radio stations installed outdoors or indoors. [Explanation of symbols]

[0018] 1 box container 1a Bottom 2 lid 3 Switch Module 4 Fixed plate 5 Input / output terminal 6 Sealing material 7 Heatsink 8 Fin 9 Recess 10 Printed Circuit Board 11 Opening periphery 12 screw holes 13 Isolator 14 Circulator 15 screws 16 Short side surface 21 Variable Attenuator 22 Fixed attenuator 30 Binding plate 100 RF Level Controller 200 Combined RF Level Controller

Claims

1. a box-shaped container that houses a printed circuit board on which a plurality of level adjustment circuits for inputting and outputting RF signals are formed and has a heat sink formed on its bottom surface; a lid that seals the box-shaped container; and a switch module that is screwed onto the outside of one short side surface of the box-shaped container and that turns on / off each of the level adjustment circuits, The RF level controller is characterized in that the lid is screwed to the box-shaped container with a sealing material placed around the opening edge of the box-shaped container sandwiched therebetween.

2. 2. The RF level controller according to claim 1, wherein contact portions for connecting the switch modules to the respective level adjustment circuits are formed on the outside of the short side surfaces, and each of the contact portions is sealed to the short side surfaces.

3. 2. The RF level controller according to claim 1, wherein input / output terminals for the RF signal are formed on the outer side of the side opposite to the short side on which the switch module is screwed, and the input / output terminals are sealed with a sealing material.

4. The device comprises: N box-shaped containers each containing a printed circuit board on which a plurality of level adjustment circuits for inputting and outputting RF signals are formed, the N containers each having a heat sink formed on its bottom surface; N lids for sealing the box-shaped containers; N switch modules for turning the level adjustment circuits ON / OFF; and a coupling plate for coupling the N box-shaped containers together; each of the N switch modules is screwed onto an outer side of one short side surface of each of the N box-shaped containers; Each of the N lids is screwed to each of the N box-shaped containers with a sealing material disposed on a periphery of an opening of each of the N box-shaped containers sandwiched therebetween, A coupled RF level controller characterized in that the N box-shaped containers, each having the N switch modules screwed therein and the N lids screwed thereon, are arranged side by side, all of the N switch modules are covered with the coupling plate, and the box-shaped containers are screwed together, thereby coupling all of the N box-shaped containers.

Images