4-terminal magnetic field antenna and antenna device comprising the same
Patent Information
- Application Number
- KR1020250028461
- Authority / Receiving Office
- KR · KR
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2026-09-14
Smart Images
Figure PAT00005_ABST
Abstract
Description
Technology Field
[0001] The present disclosure relates to an antenna device, and more specifically, to an antenna device that performs magnetic field communication. Background Technology
[0002] Magnetic field communication technology refers to wireless communication technology that utilizes a magnetic field. A magnetic field refers to the distance from when an electromagnetic field separates from an antenna until it becomes an electromagnetic wave and propagates into space; typically, it refers to the region from the antenna to wavelength / 2π. By utilizing magnetic fields, magnetic field communication technology provides communication performance similar to or superior to conventional electromagnetic waves, even in underwater, underground, metal, and inside buildings.
[0003] Conventional magnetic field antennas for medium-to-long-distance communication face the problem that they must become very large to generate resonance when implemented without utilizing integrated circuits such as capacitors or inductors. Furthermore, even when integrated circuits are used, size constraints arise in installation environments such as tunnels. For example, if a 1-meter antenna is fabricated, it corresponds to 1 / 3000 of the wavelength in the 30 kHz band, necessitating the implementation of a broadband ultra-compact antenna.
[0004] In addition, conventional antennas have the problem of very high reflection loss. In particular, in the case of micro-antennas, the radiated power becomes very low, so most of the power applied to the antenna is reflected, making it very difficult to implement technology that can send high power to the antenna terminal. Furthermore, the reflected power returns to the transmitting system and causes system failure, so the input power of the transmitting system is limited.
[0005] Considering these applications of magnetic field antennas, there are issues with power consumption due to very high reflection losses despite the fact that batteries are not easily replaced, and there are difficulties in medium-to-long distance communication. The problem to be solved
[0006] To reduce power consumption in magnetic field communication technology, we aim to provide a compact antenna device with low reflection loss and the ability to accommodate high-power inputs for medium-to-long distance communication. means of solving the problem
[0007] An embodiment for solving the above-described problem includes an antenna device comprising a controller configured to provide a first power, a 4-terminal magnetic field antenna configured to receive the first power through the first terminal and the second terminal and output a magnetic field, and a battery configured to receive the second power through the third terminal and the fourth terminal, charge the second power, and provide the second power to the controller.
[0008] Some embodiments for solving the above-described problem include an antenna device configured such that the controller comprises a receiver configured to receive the magnetic field, an antenna controller configured to analyze the magnetic field and adjust the strength of the first power, and a transmitter configured to provide the first power to the four-terminal magnetic field antenna.
[0009] Some embodiments for solving the above-described problem include an antenna device in which the 4-terminal magnetic field antenna further comprises a first loop coil including a first loop and a second loop, and a first capacitor and a second capacitor, wherein one end of the first loop is connected to the first terminal and the first capacitor and the other end is connected to the third terminal and the second capacitor, and one end of the second loop is connected to the second terminal and the first capacitor and the other end is connected to the fourth terminal and the second capacitor.
[0010] Some embodiments for solving the above-described problem include an antenna device in which the 4-terminal magnetic field antenna further comprises a first loop coil including a first loop and a second loop, a second loop coil including a third loop and a fourth loop, a first capacitor connected to the first loop coil or the second loop coil, and a second capacitor connected to the first loop coil or the second loop coil, wherein the first to fourth terminals are each connected to the first to fourth loops, and the first loop coil and the second loop coil are connected such that their magnetic field polarization directions are the same.
[0011] Some embodiments for solving the above-described problem include an antenna device in which one end of the first loop is connected to the first terminal and the first capacitor, one end of the second loop is connected to the second terminal and the first capacitor, one end of the third loop is connected to the third terminal and the second capacitor, one end of the fourth loop is connected to the fourth terminal and the second capacitor, and the first loop coil and the second loop coil are connected through the other ends of the first to fourth loops such that the magnetic field polarization direction is the same.
[0012] Some embodiments for solving the above-described problem include an antenna device in which the four-terminal magnetic field antenna further comprises a third capacitor and a fourth capacitor, the third capacitor is connected to the other end of the first loop and the other end of the second loop, and the fourth capacitor is connected to the other end of the third loop and the other end of the fourth loop.
[0013] Some embodiments for solving the above-described problem include an antenna device comprising a 4-terminal magnetic field antenna further comprising a first loop coil to an N-loop coil, a first capacitor connected to any one of the first loop coil to the N-loop coil, and a second capacitor connected to any one of the first loop coil to the N-loop coil, wherein the first terminal and the second terminal are connected to the first loop coil, the third terminal and the fourth terminal are connected to the second loop coil, and the first loop coil to the N-loop coil are connected such that the magnetic field polarization direction is the same.
[0014] Some embodiments for solving the above-described problem include an antenna device in which the 4-terminal magnetic field antenna further comprises a third capacitor connected to any one of the first loop coil to the Nth loop coil, the first capacitor is connected to the first terminal and the second terminal, and the second capacitor is connected to the third terminal and the fourth terminal.
[0015] Some embodiments for solving the above-mentioned problem include an antenna device in which the 4-terminal magnetic field antenna comprises one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil.
[0016] Some embodiments for solving the above-described problem include an antenna device configured such that the 4-terminal magnetic field antenna receives the first power through the first terminal and the second terminal in an indirect feeding manner.
[0017] Some embodiments for solving the above-mentioned problem include an antenna device configured such that the second power is supplied to the third terminal and the fourth terminal in an indirect power supply manner.
[0018] One embodiment for solving the above-described problem includes a loop coil comprising a first to fourth terminal, a first loop, and a second loop, and a first capacitor and a second capacitor, wherein one end of the first loop is connected to the first terminal and the first capacitor and the other end is connected to the third terminal and the second capacitor, one end of the second loop is connected to the second terminal and the first capacitor and the other end is connected to the fourth terminal and the second capacitor, and the antenna is configured to receive power from the first terminal and the second terminal and output the power to the third terminal and the fourth terminal, and output a magnetic field based on the power.
[0019] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna in which the loop coil comprises one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil.
[0020] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna in which the first terminal and the second terminal are configured to receive the power in an indirect feeding manner.
[0021] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna configured such that the third terminal and the fourth terminal receive the power in an indirect feeding manner.
[0022] One embodiment for solving the above-described problem includes a 4-terminal magnetic field antenna comprising a first to fourth terminal, a first loop coil to an Nth loop coil, a first capacitor connected to any one of the first loop coil to the Nth loop coil, and a second capacitor connected to any one of the first loop coil to the Nth loop coil, wherein the first terminal and the second terminal are connected to the first loop coil, the third terminal and the fourth terminal are connected to the second loop coil, and the first loop coil to the Nth loop coil are connected such that the magnetic field polarization direction is the same, and the antenna is configured to receive power from the first terminal and the second terminal and output the power to the third terminal and the fourth terminal, and output a magnetic field based on the power.
[0023] Some embodiments for solving the above-described problem further include a third capacitor connected to any one of the first loop coil to the Nth loop coil, and the first capacitor is connected to the first terminal and the second terminal, and the second capacitor is connected to the third terminal and the fourth terminal, and the four-terminal magnetic field antenna is included.
[0024] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna in which each of the first loop coil to the Nth loop coil comprises one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil.
[0025] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna in which the first terminal and the second terminal are configured to receive the power in an indirect feeding manner.
[0026] Some embodiments for solving the above-mentioned problem include a four-terminal magnetic field antenna configured such that the third terminal and the fourth terminal receive the power in an indirect feeding manner. Effects of the invention
[0027] An embodiment according to the present disclosure provides a device that transmits power to a coil through some of four terminals to perform magnetic field communication, and receives the power flowing through the coil through the remaining portions, stores it in a battery, and reuses it.
[0028] With the above configuration, it is possible to provide a compact antenna device that has low reflection loss to reduce power consumption in magnetic field communication technology, can accommodate high-power input for medium-to-long distance communication, and allows for free placement depending on the installation environment. Brief explanation of the drawing
[0029] FIG. 1 is a drawing showing a two-terminal magnetic field antenna according to a comparative example of the present disclosure. Figure 2 is a diagram showing the Smith chart evaluation results when the two-terminal magnetic field antenna of Figure 1 has a width of 1 m and is composed of 12 layers. Figure 3 is a diagram showing the S-parameter evaluation results of the two-terminal magnetic field antenna of Figure 2. Figure 4 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the two-terminal magnetic field antenna of Figure 2. FIG. 5 is a drawing showing an antenna device according to one embodiment of the present disclosure. FIG. 6 is a diagram showing the internal configuration of a controller according to one embodiment of the present disclosure. FIG. 7 is a diagram showing the internal configuration of a four-terminal magnetic field antenna according to one embodiment of the present disclosure. FIG. 8 is a drawing showing a four-terminal magnetic field antenna composed of a single loop coil according to one embodiment of the present disclosure. Figure 9 is a diagram showing the Smith chart evaluation results when the 4-terminal magnetic field antenna of Figure 8 has a width of 1 m and is composed of 12 layers. Figure 10 is a diagram showing the S-parameter evaluation results of the 4-terminal magnetic field antenna of Figure 9. Figure 11 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the 4-terminal magnetic field antenna of Figure 9. FIG. 12 is a drawing showing a four-terminal magnetic field antenna composed of two loop coils according to one embodiment of the present disclosure. Figure 13 is a diagram showing the Smith chart evaluation results when the 4-terminal magnetic field antenna of Figure 12 has a width of 1m and is composed of 12 layers. Figure 14 is a diagram showing the S-parameter evaluation results of the 4-terminal magnetic field antenna of Figure 13. Figure 15 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the 4-terminal magnetic field antenna of Figure 13. Figure 16 is a diagram showing the Smith chart evaluation results when the output terminals of a 4-terminal magnetic field antenna of Figure 13, which has a width of 1m and consists of 12 layers, are open. Figure 17 is a diagram showing the S-parameter evaluation results when the output terminals of the 4-terminal magnetic field antenna of Figure 13 are open. FIG. 18 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input when the output terminals of the 4-terminal magnetic field antenna of FIG. 13 are open. FIG. 19 is a diagram showing the arrangement of multiple capacitors of the 4-terminal magnetic field antenna of FIG. 12. FIG. 20 is a diagram showing another example of the 4-terminal magnetic field antenna of FIG. 12. FIGS. 21 and 22 are drawings showing a four-terminal magnetic field antenna composed of a plurality of loop coils according to one embodiment of the present disclosure. FIGS. 23 and FIGS. 24 are drawings showing other examples of a four-terminal magnetic field antenna (200-1) composed of one loop coil of FIG. 8. FIGS. 25 and 26 are drawings illustrating a method of transmitting and receiving power through the first to fourth terminals of a four-terminal magnetic field antenna according to one embodiment of the present disclosure. Specific details for implementing the invention
[0030] In the following, embodiments of the present disclosure will be described clearly and in detail so that a person skilled in the art can easily practice the present disclosure.
[0031] FIG. 1 is a drawing showing a two-terminal magnetic field antenna according to a comparative example of the present disclosure.
[0032] The two-terminal magnetic field antenna (10) may include a loop coil (11), a capacitor (14), a first terminal (15), and a second terminal (16). FIG. 1 illustrates a case where the two-terminal magnetic field antenna (10) is composed of seven layers, but the two-terminal magnetic field antenna (10) may be composed of any number of layers.
[0033] The loop coil (11) may include a first loop (12) and a second loop (13). The first loop (12) and the second loop (13) may be composed of a conductive material through which current flows. For example, as current is applied to the first loop (12) and the second loop (13), a magnetic field region may be generated in the two-terminal magnetic field antenna (10). For example, the two-terminal magnetic field antenna (10) may be configured to perform wireless communication through the magnetic field region generated around it. The first loop (12) and the second loop (13) may be positioned to generate the same magnetic field polarization direction by the current.
[0034] The capacitor (14) can be electrically connected to the first loop (12) and the second loop (13). For example, referring to FIG. 1, the capacitor (14) can be connected in series between the first loop (12) and the second loop (13). In another example, unlike FIG. 1, the first loop (12) and the second loop (13) can be directly connected in series, and the capacitor (14) can be connected in parallel to the first loop (12) and the second loop (13).
[0035] The capacitor (14) can generate self-resonance with the loop coil (11). For example, self-resonance can occur when the magnetic field energy generated in the loop coil (11) and the electric field energy generated in the capacitor (14) vibrate to the same value. As self-resonance occurs by adding the capacitor, a strong magnetic field region can be created around the two-terminal magnetic field antenna (10).
[0036] The loop coil (11) can receive current through the first terminal (15) and the second terminal (16). For example, the first terminal (15) and the second terminal (16) can supply current to the loop coil (11) as a single port. For example, a positive electrode (+) can be applied to the first terminal (15) and a negative electrode (-) can be applied to the second terminal (16).
[0037] Figure 2 is a diagram showing the Smith chart evaluation results when the two-terminal magnetic field antenna (10) of Figure 1 has a width of 1m and is composed of 12 layers.
[0038] Referring to Figure 2, the reference point 1+j0 on the illustrated Smith chart represents the point where the resistance of 50Ω is normalized. The real value of the impedance at the resonant frequency of 29.7 kHz was confirmed to be 0.05Ω, and as illustrated, it can be observed that the reflected wave is very high.
[0039] Figure 3 is a diagram showing the S-parameter evaluation results of the two-terminal magnetic field antenna of Figure 2.
[0040] Referring to Fig. 3, the evaluation results of the S11 parameters of the two-terminal magnetic field antenna are as shown. The resonant frequency of the two-terminal magnetic field antenna is observed to be 29.7 kHz, and it can be seen that the reflection loss is high at 99%.
[0041] Figure 4 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the two-terminal magnetic field antenna of Figure 2.
[0042] Referring to Fig. 4, it is shown that the magnetic field strength is maintained at 1.05 μA / m at the resonant frequency of 29.7 kHz of the two-terminal magnetic field antenna. The 3 dB bandwidth of the two-terminal magnetic field antenna is 16 kHz. The 3 dB bandwidth is 53% of the center frequency, indicating that a broadband magnetic field signal can be generated even at 100 m, which corresponds to a medium-to-long distance in magnetic field communication. However, as illustrated in Fig. 3, the reflection loss of the two-terminal magnetic field antenna is high, so there is a problem in increasing the magnetic field strength even if the input power is increased.
[0043] Referring to FIGS. 2 to 4, when magnetic field communication is performed through the resonance of a two-terminal magnetic field antenna, it becomes difficult to transmit high power to the antenna because the amount of reflection of the power applied to the antenna is large. In addition, since the reflected power is lost in the transmitting system, a problem arises that causes high power consumption. When such a transmitting system is implemented using a battery, there is a disadvantage of a short operating time.
[0044] FIG. 5 is a drawing showing an antenna device (1000) according to one embodiment of the present disclosure.
[0045] The antenna device (1000) may include a controller (100), a four-terminal magnetic field antenna (200), and a battery (300).
[0046] The controller (100) may be configured to provide a first power. For example, the controller (100) may supply the first power to a four-terminal magnetic field antenna (200). For example, through the first power, the four-terminal magnetic field antenna (200) may be configured to perform magnetic field communication. The controller (100) may be configured to control the overall operations of the antenna device (1000). For example, the controller (100) may be configured to control the transmission or reception of a magnetic field signal through the four-terminal magnetic field antenna (200). To this end, the controller (100) may include at least one processor. A detailed description of the controller (100) will be provided later with reference to FIG. 6.
[0047] A four-terminal magnetic field antenna (200) may include first to fourth terminals and may be configured to receive first power through the first terminal and the second terminal and output a magnetic field. For example, the first terminal and the second terminal may serve as first ports to receive first power. For example, the third terminal and the fourth terminal may serve as second ports to output second power. For example, the four-terminal magnetic field antenna (200) may be configured to receive first power from the controller (120) through the first port and output second power to the battery (300) through the second port. For example, the four-terminal magnetic field antenna (200) may be configured to receive first power from the controller (120) through the first terminal and the second terminal. For example, the four-terminal magnetic field antenna (200) may be configured to output second power to the battery (300) through the third terminal and the fourth terminal.
[0048] The four-terminal magnetic field antenna (200) may be configured to output a magnetic field through a first power. For example, the four-terminal magnetic field antenna (200) may include a loop coil and be configured to output a magnetic field by applying current to the loop coil through the first power. A detailed description of the four-terminal magnetic field antenna (200) will be provided later through FIGS. 7 to 26.
[0049] The battery (300) may be configured to receive second power through the third terminal and the fourth terminal, charge second power, and provide second power to the controller.
[0050] The battery (300) may be configured to receive second power through the third terminal and the fourth terminal. The battery (300) may receive second power through the third terminal and the fourth terminal, which are output terminals of the four-terminal magnetic field antenna (200). For example, if the reflection loss of the four-terminal magnetic field antenna (200) is large, the magnitude of the second power may be small compared to the first power. For example, the battery (300) may include a rectifier. For example, the rectifier may be configured to convert AC power into DC. For example, the rectifier may convert the received second power into DC, and the battery (300) may be configured to be charged with DC power.
[0051] The battery (300) may be configured to charge the received second power. For example, the battery (300) may store the second power as energy through a chemical reaction, etc. For example, the battery (300) may include one or more of various types of batteries, such as a lithium-ion battery, a lithium-polymer battery, a lead-acid battery, a nickel-hydrogen battery, a nickel-cadmium battery, an alkaline battery, a lithium primary battery, a fuel cell, a silver-oxide battery, and a zinc-air battery.
[0052] The battery (300) may be configured to provide charged second power to the controller (100). For example, as the battery (300) provides second power to the controller (100), the power consumed by the antenna device (1000) can be reduced. For example, if the reflection loss of the 4-terminal magnetic field antenna (200) is large, the power consumed by the antenna device (1000) may increase. For example, if the reflection loss of the 4-terminal magnetic field antenna (200) is small, the power consumed by the antenna device (1000) may decrease.
[0053] An embodiment according to the present disclosure provides a device that transmits power to a coil through some of four terminals to perform magnetic field communication, and receives the power flowing through the coil through the remaining portions, stores it in a battery, and reuses it.
[0054] With the above configuration, it is possible to provide a compact antenna device that has low reflection loss to reduce power consumption in magnetic field communication technology, can accommodate high-power input for medium-to-long distance communication, and allows for free placement depending on the installation environment.
[0055] FIG. 6 is a diagram showing the internal configuration of a controller (100) according to one embodiment of the present disclosure.
[0056] Referring to FIG. 6, the controller (100) may include a receiver (110), an antenna controller (120), and a transmitter (130). The following description will be made with reference to FIG. 5.
[0057] The receiver (110) may be configured to receive a magnetic field. For example, the receiver (110) may be configured to receive a magnetic field output by a four-terminal magnetic field antenna (200). For example, the receiver (110) may include one or more of various types of magnetic field sensors, such as a magnetic induction coil type sensor, a magnetic field flux gate type sensor, a Giant Magneto-Impedance (GMI) type sensor, a Giant Magnetoresistance (GMR) type sensor, and a Tunneling Magnetoresistance (TMR) type sensor.
[0058] An antenna controller (120) may be configured to analyze a magnetic field and adjust the strength of the power output by the controller (100). For example, referring together with FIG. 5, the antenna controller (120) may be configured to analyze a magnetic field received by a receiver (110) and adjust the strength of the first power. For example, the antenna controller (120) may analyze the quality of communication and adjust the first power output so that the controller (100) outputs an optimal magnetic field strength. For example, the antenna controller (120) may be configured to analyze the strength of the received magnetic field and adjust the first power to the minimum applied power that enables communication.
[0059] The transmitter (130) may be configured to provide the output power of the controller (100) to the outside. For example, referring together with FIG. 5, the transmitter (130) may be configured to provide the first power to the four-terminal magnetic field antenna (200). For example, the receiver (110) may receive the magnetic field output by the four-terminal magnetic field antenna (200), the antenna controller (120) may analyze the magnetic field to adjust the first power, and the transmitter (130) may be configured to provide the adjusted first power to the four-terminal magnetic field antenna (200).
[0060] FIG. 7 is a diagram showing the internal configuration of a four-terminal magnetic field antenna according to one embodiment of the present disclosure.
[0061] The 4-terminal magnetic field antenna (200) may include loop coils (210), capacitors (220), and four input / output terminals (230).
[0062] According to one embodiment, the four-terminal magnetic field antenna (200) may include one or more loop coils (210) and one or more capacitors (220). For example, a magnetic field region may be created around the four-terminal magnetic field antenna (200) through the self-resonance of the loop coils (210) and capacitors (220).
[0063] The 4-terminal magnetic field antenna (200) may include 4 input / output terminals (230). For example, each of the loop coils (210) may include 4 terminals, and the loop coils (210) may be connected through the 4 terminals. For example, some of the 4 terminals of each of the loop coils (210) may be used to connect the loop coils (210), and the remaining portion may be used as 4 input / output terminals (230). In this case, the remaining portion of the 4 terminals of each of the loop coils (210) may be 4.
[0064] According to some embodiments, the loop coils (210) and capacitors (220) may be arranged in various ways depending on the installation space of the four-terminal magnetic field antenna (200). For example, the loop coils (210) may be arranged in various ways, such as in a line or in a circle. For example, each of the loop coils (210) can generate higher magnetic field energy as the number of loops and the opening area of the coil increase. Depending on the installation space, the number of loops and the opening area of each of the loop coils (210) may be formed differently. For example, if the length of the coil is fixed, the opening area becomes wider when the number of loops is 1, but the highest magnetic field energy can be generated. For example, the capacitors (220) may be placed between the loop coils (210) or may not be placed. For example, there may be at least two capacitors (220). For example, some of the capacitors (220) may be connected between the four input / output terminals (230) to increase the magnetic field strength. Various examples of arranging the loop coils (210) and capacitors (220) will be described later through FIGS. 8 to 26.
[0065] FIG. 8 is a drawing showing a four-terminal magnetic field antenna (200-1) composed of a single loop coil according to one embodiment of the present disclosure.
[0066] The four-terminal magnetic field antenna (200-1) may include a first loop coil (210-1), a first capacitor (221-1), a second capacitor (222-1), and first terminals (231-1) through fourth terminals (234-1). For example, the first loop coil (210-1) may be configured as a right-angle loop coil. For example, the four-terminal magnetic field antenna (200-1) may be an example of the four-terminal magnetic field antenna (200) of FIG. 7.
[0067] The first loop coil (210-1) may include a first loop (211-1) and a second loop (212-1). Referring to FIG. 8, the first loop (211-1) and the second loop (212-1) may be arranged so that their opening directions are the same. For example, as current is applied through the first terminal (231-1) to the fourth terminal (234-1), the first loop (211-1) and the second loop (212-1) may be arranged so that the direction of magnetic field polarization formed is the same. FIG. 8 illustrates the case where the first loop coil (210-1) is composed of seven layers, but the first loop coil (210-1) may be composed of any layer.
[0068] One end of the first loop (211-1) is connected to the first terminal (231-1) and the first capacitor (221-1), and the other end of the first loop (211-1) can be connected to the third terminal (233-1) and the second capacitor (222-1).
[0069] One end of the second loop (212-1) is connected to the second terminal (232-1) and the first capacitor (221-1), and the other end of the second loop (212-1) can be connected to the fourth terminal (234-1) and the second capacitor (222-1).
[0070] For example, the first terminal (231-1) and the second terminal (232-1) can supply current to the first loop coil (210-1) as a single port. For example, a positive electrode (+) can be applied to the first terminal (231-1) and a negative electrode (-) can be applied to the second terminal (232-1). Conversely, the third terminal (233-1) and the fourth terminal (234-1) can supply current to the first loop coil (210-1) as a single port. For example, a positive electrode (+) can be applied to the third terminal (233-1) and a negative electrode (-) can be applied to the fourth terminal (234-1).
[0071] Figure 9 is a diagram showing the Smith chart evaluation results when the 4-terminal magnetic field antenna (200-1) of Figure 8 has a width of 1m and is composed of 12 layers.
[0072] Referring to Fig. 9, the reference point 1+j0 on the illustrated Smith chart represents the point where the resistance is normalized to 50Ω. The real value of the impedance at the resonant frequency of 28.6 kHz was confirmed to be 50.7Ω. As the impedance is matched to near 50Ω, it can be expected that the reflection loss will be low.
[0073] FIG. 10 is a diagram showing the S-parameter evaluation results of the 4-terminal magnetic field antenna (200-1) of FIG. 9.
[0074] Referring to FIG. 10, the S11 parameter evaluation result of the 4-terminal magnetic field antenna (200-1) is shown as a solid line, and the S21 parameter evaluation result is shown as a dotted line.
[0075] The resonant frequency of the 4-terminal magnetic field antenna (200-1) is observed to be 28.6 [kHz], and checking the S11 parameter evaluation results reveals that the reflection loss is 4%. Checking the S21 parameter evaluation results reveals that the transmission efficiency is 94%.
[0076] Referring to FIG. 8, when current is input through the first terminal (231-1) and the second terminal (232-1), the output terminals can be the third terminal (233-1) and the fourth terminal (234-1). Referring to the Smith chart evaluation result of FIG. 9 and the S-parameter evaluation result of FIG. 10, it can be seen that the power applied at the input terminals is matched so that most of it flows to the output terminals.
[0077] FIG. 11 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the 4-terminal magnetic field antenna (200-1) of FIG. 9.
[0078] Referring to FIG. 11, it is shown that the magnetic field strength is maintained at 1.12 μA / m at the resonant frequency of 28.6 kHz of the 4-terminal magnetic field antenna (200-1). The 3 dB bandwidth of the 4-terminal magnetic field antenna (200-1) is shown to be 9 kHz. The 3 dB bandwidth is shown to be 31.5% of the center frequency, indicating that a broadband magnetic field signal can be generated even at 100 m, which corresponds to a medium-to-long distance in magnetic field communication. Referring to FIG. 9 through FIG. 11, it is shown that the 4-terminal magnetic field antenna (200-1) enables broadband, high-power magnetic field communication by having low reflection loss even when the applied input power is increased.
[0079] FIG. 12 is a drawing showing a four-terminal magnetic field antenna (200-2) composed of two loop coils according to one embodiment of the present disclosure.
[0080] The four-terminal magnetic field antenna (200-2) may include a first loop coil (210a-2), a second loop coil (210b-2), a first capacitor (221-2), a second capacitor (222-2), and first terminals (231-2) to fourth terminals (234-2). For example, the four-terminal magnetic field antenna (200-2) may be an example of the four-terminal magnetic field antenna (200) of FIG. 7.
[0081] The first loop coil (210a-2) may include a first loop (211-2) and a second loop (212-2). Referring to FIG. 12, the first loop (211-2) and the second loop (212-2) may be arranged so that their opening directions are the same. For example, as current is applied through the first terminal (231-2) to the fourth terminal (234-2), the first loop (211-2) and the second loop (212-2) may be arranged so that the magnetic field polarization direction formed is the same. For example, the magnetic field polarization direction of the first loop (211-2) and the second loop (212-2) may be the first direction. FIG. 12 illustrates the case where the first loop coil (230a-2) is composed of seven layers, but the first loop coil (230a-2) may be composed of any layer.
[0082] The second loop coil (210b-2) may include a third loop (213-2) and a fourth loop (214-2). Referring to FIG. 12, the third loop (213-2) and the fourth loop (214-2) may be arranged so that their opening directions are the same. For example, as current is applied through the first terminal (231-2) to the fourth terminal (234-2), the third loop (213-2) and the fourth loop (214-2) may be arranged so that the magnetic field polarization directions formed are the same. For example, the magnetic field polarization directions of the third loop (213-2) and the fourth loop (214-2) may be the first direction. FIG. 12 illustrates the case where the second loop coil (230b-2) is composed of seven layers, but the second loop coil (230b-2) may be composed of any layer.
[0083] The first loop coil (210a-2) and the second loop coil (210b-2) can be connected so that the direction of magnetic field polarization formed is the same. For example, current can be applied through the first terminal (231-2) and the second terminal (232-2), or the third terminal (233-2) and the fourth terminal (234-2). For example, both the first loop coil (210a-2) and the second loop coil (210b-2) can be connected so that the magnetic field is polarized in the first direction. For example, when current is applied through the first terminal (231-2) and the second terminal (232-2), the connecting portion (240-2) of the first loop coil (210a-2) and the second loop coil (210b-2) can be connected by cross-connecting wires so that the direction of magnetic field polarization is the same.
[0084] The first capacitor (221-2) can be connected to the first loop coil (210a-2). For example, one end of the first capacitor (221-2) can be connected to the first loop (211-2) and the first terminal (231-2), and the other end of the first capacitor (221-2) can be connected to the second loop (212-2) and the second terminal (232-2).
[0085] The second capacitor (222-2) can be connected to the second loop coil (210b-2). For example, one end of the second capacitor (222-2) can be connected to the third loop (213-2) and the third terminal (233-2), and the other end of the second capacitor (222-2) can be connected to the fourth loop (214-2) and the fourth terminal (234-2).
[0086] FIG. 12 illustrates a case where the first capacitor (221-2) and the second capacitor (222-2) are positioned between the first terminal (231-2) and the fourth terminal (233-2), but the first capacitor (221-2) and the second capacitor (222-2) may be positioned in the connection portion (240-2). A detailed description of the arrangement of the capacitors of the four-terminal magnetic field antenna will be given later in FIG. 19.
[0087] FIG. 13 is a diagram showing the Smith chart evaluation results when the 4-terminal magnetic field antenna (200-2) of FIG. 12 has a width of 1m and is composed of 12 layers.
[0088] Referring to Fig. 13, the reference point 1+j0 on the illustrated Smith chart represents the point where the resistance is normalized to 50Ω. The real value of the impedance at the resonant frequency of 26 kHz was confirmed to be 50.1Ω. As the impedance is matched to near 50Ω, it can be expected that the reflection loss will be low.
[0089] FIG. 14 is a diagram showing the S-parameter evaluation results of the 4-terminal magnetic field antenna (200-2) of FIG. 13.
[0090] Referring to FIG. 14, the S11 parameter evaluation result of the 4-terminal magnetic field antenna (200-2) is shown as a solid line, and the S21 parameter evaluation result is shown as a dotted line.
[0091] The resonant frequency of the 4-terminal magnetic field antenna (200-2) is observed to be 26 kHz, and checking the S11 parameter evaluation results reveals that the reflection loss is 0.1%. Checking the S21 parameter evaluation results reveals that the transmission efficiency is 99%.
[0092] Referring to FIG. 12, when current is input through the first terminal (231-2) and the second terminal (232-2), the output terminals can be the third terminal (233-2) and the fourth terminal (234-2). Referring to the Smith chart evaluation result of FIG. 13 and the S-parameter evaluation result of FIG. 14, it can be seen that the power applied at the input terminals is matched so that most of it flows to the output terminals.
[0093] FIG. 15 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input to the 4-terminal magnetic field antenna (200-2) of FIG. 13.
[0094] Referring to FIG. 15, it is shown that the magnetic field strength is maintained at 1.27 μA / m at the resonant frequency of 26 kHz of the 4-terminal magnetic field antenna (200-2). The 3 dB bandwidth of the 4-terminal magnetic field antenna (200-2) is shown to be 14 kHz. The 3 dB bandwidth is shown to be 53.8% of the center frequency, indicating that a broadband magnetic field signal can be generated even at 100 m, which corresponds to a medium-to-long distance in magnetic field communication. Referring to FIG. 13 to FIG. 15, it is shown that the 4-terminal magnetic field antenna (200-2) enables broadband, high-power magnetic field communication by having low reflection loss even when the applied input power is increased.
[0095] Comparing FIGS. 9 to 11 with FIGS. 13 to 15, the 4-terminal magnetic field antenna (200-2) having two loop coils of FIG. 12 has lower reflection loss, higher transmission efficiency, and can communicate over a relatively wideband compared to the 4-terminal magnetic field antenna (200-1) having one loop coil of FIG. 8.
[0096] FIG. 16 is a diagram showing the Smith chart evaluation results when the output terminals of a 4-terminal magnetic field antenna (200-2) of FIG. 13, which has a width of 1m and consists of 12 layers, are open. For example, when current is input through the first and second terminals, the third and fourth terminals may be open.
[0097] Referring to Fig. 16, the reference point 1+j0 on the illustrated Smith chart represents the point where the resistance is normalized to 50Ω. The real value of the impedance at the resonant frequency of 27.5 kHz was confirmed to be 2.9Ω. As the impedance is mismatched, high reflection loss can be expected.
[0098] FIG. 17 is a diagram showing the S-parameter evaluation results when the output terminals of the 4-terminal magnetic field antenna (200-2) of FIG. 13 are open.
[0099] Referring to FIG. 17, the S11 parameter evaluation result of a 4-terminal magnetic field antenna (200-2) with open output terminals is as shown. The resonant frequency of the 4-terminal magnetic field antenna (200-2) with open output terminals is observed to be 27.5 kHz, and upon checking the S11 parameter evaluation result, it can be seen that the reflection loss is high at 94%.
[0100] FIG. 18 is a diagram showing the results of evaluating the magnetic field strength at a point 100m away from the antenna when 1[Watt] of power is input when the output terminals of the 4-terminal magnetic field antenna (200-2) of FIG. 13 are open.
[0101] Referring to FIG. 18, it is shown that the magnetic field strength is maintained at 2.60 μA / m at the resonant frequency of 27.5 kHz of the 4-terminal magnetic field antenna (200-2) with the output terminals open. The 3 dB bandwidth of the 4-terminal magnetic field antenna (200-2) with the output terminals open is shown to be 7 kHz. The 3 dB bandwidth is shown to be 26.9% of the center frequency, indicating that a broadband magnetic field signal can be generated even at 100 m, which corresponds to a medium-to-long distance in magnetic field communication. Referring to FIG. 15 as well, it can be seen that when the output terminals of the 4-terminal magnetic field antenna (200-2) are open, the magnetic field strength increases and the reflection loss increases. As reflection loss increases, problems arise such as difficulty in transmitting high power and high power consumption, but in certain situations, if you want to increase the strength of the magnetic field, the output terminals of the 4-terminal magnetic field antenna (200-2) can be opened.
[0102] FIG. 19 is a diagram showing the arrangement of multiple capacitors (221-2 to 224-2) of the 4-terminal magnetic field antenna (200-2) of FIG. 12.
[0103] The 4-terminal magnetic field antenna (200-2) may include a plurality of capacitors (211-2 to 224-2). FIG. 19 illustrates a case where the 4-terminal magnetic field antenna (200-2) includes four capacitors, but the 4-terminal magnetic field antenna (200-2) may include two or more and four or fewer capacitors. For example, the 4-terminal magnetic field antenna (200-2) of FIG. 19 may be configured in a form in which two 4-terminal magnetic field antennas (200-1) of FIG. 8 are connected.
[0104] Each of the plurality of capacitors (221-2 to 224-2) may be connected to the first loop coil (210a-2) or the second loop coil (210b-2). For example, depending on the number of the plurality of capacitors (221-2 to 224-2), the plurality of capacitors (221-2 to 224-2) may be placed in any area between the first loop coil (210a-2) or the second loop coil (210b-2). For example, referring to FIG. 19, the first area (241-2) may represent the area where the first capacitor (221-2) is placed, the second area (242-2) may represent the area where the second capacitor (222-2) is placed, the third area (243-2) may represent the area where the third capacitor (223-2) is placed, and the fourth area (244-2) may represent the area where the fourth capacitor (224-2) is placed. For example, two to four capacitors may be placed in any of the first region (241-2) to the fourth region (244-2). For example, if the four-terminal magnetic field antenna (200-2) is composed of two capacitors, the two capacitors may be placed in the second region (242-2) and the third region (243-2). For example, if the four-terminal magnetic field antenna (200-3) is composed of three capacitors, the three capacitors may be placed in the second region (242-2), the third region (243-2), and the fourth region (244-2). For example, capacitors may always be placed between the first terminal to the fourth terminal.
[0105] FIG. 20 is a drawing showing another example of the 4-terminal magnetic field antenna (200-2) of FIG. 12.
[0106] Referring to FIG. 20, the second loop coil (210b-2) of FIG. 12 can be connected to the first loop coil (210a-2) by rotating it 180 degrees. For example, the third terminal (233-2) and the fourth terminal (234-2) of FIG. 12 can be connected to the first loop coil (210a-2). For example, in FIG. 20, the first loop coil (210a-2) and the second loop coil (210b-2) can be connected so that the direction of magnetic field polarization formed is the same. For example, both the first loop coil (210a-2) and the second loop coil (210b-2) can be connected so that the magnetic field is polarized in the first direction. The connecting portion (250-2) of the first loop coil (210a-2) and the second loop coil (210b-2) can have wires connected in parallel so that the direction of magnetic field polarization is the same.
[0107] FIGS. 21 and 22 are drawings showing a four-terminal magnetic field antenna (200-3) composed of a plurality of loop coils according to one embodiment of the present disclosure.
[0108] Referring to FIG. 21, the four-terminal magnetic field antenna (200-3) may include a first loop coil (211-3) to an Nth loop coil (21N-3). For example, the four-terminal magnetic field antenna (200-3) may be an example of the four-terminal magnetic field antenna (200) of FIG. 7.
[0109] The first capacitor may be connected to any one of the first loop coil (211-3) to the Nth loop coil (21N-3), and the second capacitor may be connected to the first loop coil (211-3) to the Nth loop coil (21N-3). For example, a plurality of capacitors may be connected to each of the first loop coil (211-3) to the Nth loop coil (21N-3). For example, the number of the plurality of capacitors may be 2 or more and 2N or less. For example, the manner in which the plurality of capacitors are connected to the first loop coil (211-3) to the Nth loop coil (21N-3) may be as described in FIG. 19.
[0110] The first terminal (231-3) and the second terminal (232-2) are connected to the first loop coil (211-3), and the third terminal (233-3) and the fourth terminal (234-3) can be connected to the Nth loop coil (21N-3).
[0111] Referring to FIG. 22, some of the first loop coil (211-3) to the Nth loop coil (21N-3) can be connected by rotating 180 degrees as described in FIG. 20.
[0112] In FIGS. 21 and 22, the first loop coil (211-3) to the Nth loop coil (21N-3) can be connected such that the direction of magnetic field polarization formed is the same. For example, the first loop coil (211-3) to the Nth loop coil (21N-3) can all be connected such that the magnetic field is polarized in the first direction.
[0113] As shown in FIGS. 21 and 22, the 4-terminal magnetic field antenna (200-3) can be positioned by freely adjusting the antenna length according to the installation area.
[0114] FIGS. 23 and FIGS. 24 are drawings showing other examples of a four-terminal magnetic field antenna (200-1) composed of a single loop coil of FIG. 8. Hereinafter, the description will be made with reference to FIG. 8.
[0115] Referring to FIG. 23, the first loop coil (210-1) of FIG. 8 may be composed of a cylindrical loop coil.
[0116] Referring to FIG. 24, the first loop coil (210-1) of FIG. 8 may be configured as a right-angle spiral coil. Unlike what is shown, the first loop coil (210-1) may be configured as a circular spiral coil. When the first loop coil (210-1) is configured as a spiral coil, it can be manufactured to be thinner than a right-angle loop coil or a cylindrical loop coil. That is, as illustrated in FIG. 8 through FIG. 24, the four-terminal magnetic field antenna can be manufactured in various ways depending on the installation environment.
[0117] FIGS. 25 and 26 are drawings illustrating a method in which a 4-terminal magnetic field antenna (200-4) transmits and receives power through the first to fourth terminals according to one embodiment of the present disclosure.
[0118] Referring to FIG. 25, the 4-terminal magnetic field antenna (200-4) can receive a first power through the first terminal (231) and the second terminal (232). For example, unlike FIG. 8, the 4-terminal magnetic field antenna (200-4) can receive the first power in an indirect feeding manner. For example, the first power is applied to the first terminal (231) and the second terminal (232), and the first power can be indirectly applied to the 4-terminal magnetic field antenna (200-4) according to the magnetic field induction phenomenon.
[0119] The 4-terminal magnetic field antenna (200-4) may be configured to output a second power through the third terminal (233) and the fourth terminal (234). For example, the first terminal (231) and the second terminal (232) may be configured to apply the first power to the 4-terminal magnetic field antenna (200-4) in an indirect feeding manner, and the third terminal (233) and the fourth terminal (234) may be configured to directly output the second power.
[0120] Referring to FIG. 26, the 4-terminal magnetic field antenna (200-4) can receive a first power through the first terminal (231) and the second terminal (232). For example, unlike FIG. 8, the 4-terminal magnetic field antenna (200-4) can receive the first power in an indirect feeding manner. For example, the first power is applied to the first terminal (231) and the second terminal (232), and the first power can be indirectly applied to the 4-terminal magnetic field antenna (200-4) according to the magnetic field induction phenomenon.
[0121] The 4-terminal magnetic field antenna (200-4) may be configured to provide second power to the third terminal (233) and the fourth terminal (234) via an indirect feeding method. For example, the first terminal (231) and the second terminal (232) may be configured to apply first power to the 4-terminal magnetic field antenna (200-4) via an indirect feeding method, and to provide second power to the third terminal (233) and the fourth terminal (234) of the 4-terminal magnetic field antenna (200-4) via an indirect feeding method.
[0122] An embodiment according to the present disclosure provides a device that transmits power to a coil through some of four terminals to perform magnetic field communication, and receives the power flowing through the coil through the remaining portions, stores it in a battery, and reuses it.
[0123] As explained above, to reduce power consumption in magnetic field communication technology, it is possible to provide a compact antenna device that has low reflection loss, can accommodate high-power input for medium-to-long distance communication, and allows for free placement depending on the installation environment.
[0124] The above descriptions are specific embodiments for carrying out the present disclosure. The present disclosure will include not only the embodiments described above, but also embodiments that are simply modified or can be easily modified. Furthermore, the present disclosure will include technologies that can be easily modified and implemented using the embodiments. Accordingly, the scope of the present disclosure should not be limited to the embodiments described above, but should be defined by the claims set forth below as well as equivalents to the claims of this invention. Explanation of the symbols
[0125] 200: 4-terminal magnetic field antenna
Claims
Claim 1 An antenna device comprising: a controller configured to provide a first power; a four-terminal magnetic field antenna configured to receive the first power through the first terminal and the second terminal and output a magnetic field, and having first to fourth terminals for transmitting and receiving powers; and a battery configured to receive the second power through the third terminal and the fourth terminal, charge the second power, and provide the second power to the controller. Claim 2 An antenna device according to claim 1, wherein the controller comprises: a receiver configured to receive the magnetic field; an antenna controller configured to analyze the magnetic field and adjust the strength of the first power; and a transmitter configured to provide the first power to the four-terminal magnetic field antenna. Claim 3 In claim 1, the 4-terminal magnetic field antenna comprises: a first loop coil including a first loop and a second loop; and further comprises a first capacitor and a second capacitor, wherein one end of the first loop is connected to the first terminal and the first capacitor and the other end is connected to the third terminal and the second capacitor, and one end of the second loop is connected to the second terminal and the first capacitor and the other end is connected to the fourth terminal and the second capacitor. Claim 4 The antenna device according to claim 1, wherein the four-terminal magnetic field antenna further comprises: a first loop coil including a first loop and a second loop; a second loop coil including a third loop and a fourth loop; a first capacitor connected to the first loop coil or the second loop coil; and a second capacitor connected to the first loop coil or the second loop coil, wherein the first to fourth terminals are each connected to the first to fourth loops, and the first loop coil and the second loop coil are connected such that their magnetic field polarization directions are the same. Claim 5 An antenna device according to claim 4, wherein one end of the first loop is connected to the first terminal and the first capacitor, one end of the second loop is connected to the second terminal and the first capacitor, one end of the third loop is connected to the third terminal and the second capacitor, one end of the fourth loop is connected to the fourth terminal and the second capacitor, and the first loop coil and the second loop coil are connected through the other ends of the first to fourth loops such that the magnetic field polarization direction is the same. Claim 6 An antenna device according to claim 5, wherein the 4-terminal magnetic field antenna further comprises a third capacitor and a fourth capacitor, wherein the third capacitor is connected to the other end of the first loop and the other end of the second loop, and the fourth capacitor is connected to the other end of the third loop and the other end of the fourth loop. Claim 7 The antenna device according to claim 1, wherein the four-terminal magnetic field antenna further comprises: a first loop coil to an N-loop coil; a first capacitor connected to any one of the first loop coil to the N-loop coil; and a second capacitor connected to any one of the first loop coil to the N-loop coil, wherein the first terminal and the second terminal are connected to the first loop coil, the third terminal and the fourth terminal are connected to the second loop coil, and the first loop coil to the N-loop coil are connected such that the magnetic field polarization direction is the same. Claim 8 An antenna device according to claim 7, wherein the 4-terminal magnetic field antenna further comprises a third capacitor connected to any one of the first loop coil to the Nth loop coil, the first capacitor is connected to the first terminal and the second terminal, and the second capacitor is connected to the third terminal and the fourth terminal. Claim 9 In claim 1, the 4-terminal magnetic field antenna is an antenna device comprising one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil. Claim 10 In claim 1, the 4-terminal magnetic field antenna is an antenna device configured to receive the first power through the first terminal and the second terminal in an indirect feeding manner. Claim 11 An antenna device according to claim 1, wherein the second power is configured to be supplied to the third terminal and the fourth terminal in an indirect power supply manner. Claim 12 A four-terminal magnetic field antenna comprising: a first to fourth terminal; a loop coil including a first loop and a second loop; and a first capacitor and a second capacitor, wherein one end of the first loop is connected to the first terminal and the first capacitor and the other end is connected to the third terminal and the second capacitor, one end of the second loop is connected to the second terminal and the first capacitor and the other end is connected to the fourth terminal and the second capacitor, and configured to receive power from the first terminal and the second terminal and output the power to the third terminal and the fourth terminal, and output a magnetic field based on the power. Claim 13 In claim 12, the loop coil is a four-terminal magnetic field antenna comprising one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil. Claim 14 In claim 12, the first terminal and the second terminal are a four-terminal magnetic field antenna configured to receive the power in an indirect feeding manner. Claim 15 In claim 12, the third terminal and the fourth terminal are configured to receive the power via an indirect power supply method, forming a four-terminal magnetic field antenna. Claim 16 A four-terminal magnetic field antenna comprising: a first to fourth terminal; a first loop coil to an Nth loop coil; a first capacitor connected to any one of the first to Nth loop coils; and a second capacitor connected to any one of the first to Nth loop coils, wherein the first terminal and the second terminal are connected to the first loop coil, the third terminal and the fourth terminal are connected to the second loop coil, and the first to Nth loop coils are connected such that their magnetic field polarization directions are the same, and configured to receive power from the first terminal and the second terminal and output the power to the third terminal and the fourth terminal, and output a magnetic field based on the power. Claim 17 A four-terminal magnetic field antenna according to claim 16, further comprising a third capacitor connected to any one of the first loop coil to the Nth loop coil, wherein the first capacitor is connected to the first terminal and the second terminal, and the second capacitor is connected to the third terminal and the fourth terminal. Claim 18 In claim 16, each of the first loop coil to the Nth loop coil comprises one or more of a right-angle loop coil, a cylindrical loop coil, a right-angle spiral coil, and a circular spiral coil, forming a four-terminal magnetic field antenna. Claim 19 In claim 16, the first terminal and the second terminal are a four-terminal magnetic field antenna configured to receive the power in an indirect feeding manner. Claim 20 In claim 16, the 4-terminal magnetic field antenna configured such that the third terminal and the fourth terminal receive the power via an indirect power supply method.