Broadband antenna and radar having same

Abstract

Disclosed are a broadband antenna and a radar having same The broadband antenna according to a disclosed embodiment comprises: a substrate; one or more radiators arranged on one side of the substrate; one or more slots extending on the radiator along a first direction from one end to the other end to separate the radiator into a plurality of parts; and an impedance component provided in the slot.

Description

Broadband antenna and radar equipped therewith

[0001] An embodiment of the present invention is a technology related to a wideband antenna.

[0002] Impulse-like signals (i.e., impulse-like signals) are waveforms with a pulse width of several picoseconds in the time domain, and the corresponding pulse spectrum has a bandwidth of several gigahertz. These impulse-like signals are primarily used as antenna input signals in short-range impulse radar applications.

[0003] Here, short-range impulse radars, based on impulse-like signals transmitted from an antenna, receive pulses reflected from objects within a detection range of 50 cm to 5 m, and then undergo a series of signal processing processes to obtain additional information, such as object location information or high-resolution images. Thus, in applications such as imaging and location information of short-range objects, resolution, the ability to distinguish between two objects, is crucial, and this is closely related to the antenna bandwidth. The wider the antenna bandwidth, the better the resolution.

[0004] Meanwhile, near-range impulse radars utilize penetrating radars, such as Ground-Penetrating Radar (GPR) or Through-The-Wall Radar (TWR). The antenna's operating frequency must be in a low-frequency band to facilitate object penetration. However, the physical size of the antenna is limited, requiring a method that allows the antenna to operate in a low-frequency band while maintaining a wide frequency band within a limited antenna size.

[0005] In addition, the signal input to the antenna in the penetrating radar is mainly a first-order differentiated Gaussian pulse, and when this input signal is radiated through the antenna, it must have little dispersion and little distortion. Therefore, when designing the antenna, it is necessary to design it so as to well reflect the characteristics of this input signal.

[0006] An embodiment of the present invention provides a wideband antenna capable of operating normally in a low frequency band and a radar having the same.

[0007] An embodiment of the present invention provides a wideband antenna capable of improving antenna performance by improving current flow in a radiator, and a radar having the same.

[0008] A broadband antenna according to one embodiment disclosed includes: a substrate; one or more radiators provided on one surface of the substrate; one or more slots provided from one end to the other end along a first direction in the radiator to separate the radiator into a plurality of parts; and an impedance component provided in the slot.

[0009] The above impedance component can be provided by connecting parts of the radiator separated by the slot in the slot.

[0010] The above slots may be provided in a plurality of positions spaced apart from each other in a second direction perpendicular to the first direction in the radiator, and the impedance components may be provided by being inserted into each of the plurality of slots.

[0011] The impedance value of the impedance component inserted into each slot can be set differently depending on the position of the slot based on the power supply point provided on the above substrate.

[0012] The above-mentioned radiator may include a closed surface formed by a first curve having a first exponential function shape based on a power supply point provided on the substrate and a second curve having a second exponential function shape based on the power supply point.

[0013] The impedance value of the impedance component inserted into each of the above slots can be determined based on the total impedance value of the impedance components inserted into each slot, the diagonal length of the radiator, and the position of the corresponding slot according to the total number of slots.

[0014] The impedance value of the impedance component inserted into the above slot can be set using the mathematical formula below.

[0015] (mathematical formula)

[0016]

[0017] Z i : Impedance value of the impedance component inserted into the i-th slot

[0018] Z scale : Pre-set slot impedance adjustment factor

[0019] L: diagonal length of the radiator

[0020] : Position of the i-th slot according to the total number of slots

[0021] The above slot impedance adjustment factor (Z scale ) can be determined by the following mathematical formula.

[0022] (mathematical formula)

[0023]

[0024] Z total : Total impedance value of the impedance components inserted into each slot

[0025] N: Total number of slots

[0026] The above wideband antenna may further include one or more additional slots formed in each part of the radiator.

[0027] The above additional slot may be provided adjacent to the impedance component in each part of the radiator so that current flow from the radiator is directed toward the impedance component by detouring along the additional slot.

[0028] The above-mentioned radiator includes a closed surface formed of a first curve having a first exponential function shape based on a feeding point provided on the substrate and a second curve having a second exponential function shape based on the feeding point, wherein the first curve is determined by a first slope parameter involved in a slope at a starting point of the first curve and a second slope parameter involved in a slope at an end point of the first curve, and the second curve can be determined based on a third slope parameter involved in a slope at a starting point of the second curve and a fourth slope parameter involved in a slope at an end point of the second curve.

[0029] The first slope parameter to the fourth slope parameter may be determined as values ​​that optimize the performance of the wideband antenna based on values ​​of evaluation factors calculated based on a time-domain reflection pulse of the wideband antenna and values ​​of evaluation factors calculated based on a time-domain radiation pulse of the wideband antenna.

[0030] A broadband antenna according to another disclosed embodiment comprises: a substrate; a feeding point provided on the substrate; a radiator provided symmetrically on one side of the substrate with respect to the feeding point; one or more slots provided from one end to the other in a vertical direction on the radiator to separate the radiator into a plurality of parts; and an impedance component provided in the slot.

[0031] According to the disclosed embodiment, a wideband antenna can be designed by well reflecting the characteristics of an input signal of the wideband antenna in the time domain, thereby optimizing the radiation performance of the wideband antenna.

[0032] In addition, by forming a slot in a wideband antenna and inserting an impedance component into the slot, when a current flows in the radiator, the current is absorbed or attenuated by the impedance component, so that the size of the current reflected from the radiator can be minimized, thereby enabling the wideband antenna to operate well in a low-frequency band even with a limited size.

[0033] FIG. 1 is a drawing showing a wideband antenna according to one embodiment of the present invention.

[0034] Figure 2 is a graph comparing antenna characteristics when the closed surface shape of the radiator is changed by changing the slope parameter in one embodiment of the present invention.

[0035] FIG. 3 is a block diagram illustrating a computing environment including a computing device suitable for use in exemplary embodiments.

[0036] Figure 4 is a flowchart showing a design method of a wideband antenna according to one embodiment of the present invention.

[0037] FIG. 5 is a graph showing a reflected pulse in the time domain of a wideband antenna in one embodiment of the present invention.

[0038] FIG. 6 is a graph showing a time-domain radiation pulse of a wideband antenna in one embodiment of the present invention.

[0039] FIG. 7 is a diagram showing each evaluation factor and evaluation index (EF) of a wideband antenna according to a change in the value of the first slope parameter (n1) in one embodiment of the present invention.

[0040] FIG. 8 is a diagram showing a wideband antenna shape when the first slope parameter (n1) to the fourth slope parameter (n4) are at optimal values ​​in one embodiment of the present invention.

[0041] FIG. 9 is a drawing showing a wideband antenna according to a second embodiment of the present invention.

[0042] FIG. 10 and FIG. 11 are graphs showing the reflection coefficient and VSWR of a wideband antenna in the case where a slot is formed in the radiator and an impedance component is inserted and in the case where it is not formed in the second embodiment of the present invention.

[0043] FIG. 12 and FIG. 13 are graphs showing the time domain reflection pulse and radiation pulse of a wideband antenna in the case where a slot is formed in the radiator and an impedance component is inserted and in the case where it is not formed in the second embodiment of the present invention.

[0044] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. The following detailed description is provided to facilitate a comprehensive understanding of the methods, devices, and / or systems described herein. However, these are merely examples and the present invention is not limited thereto.

[0045] In describing embodiments of the present invention, if a detailed description of a known technology related to the present invention is judged to unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, the terms described below are terms defined in consideration of their functions in the present invention, and this may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout this specification. The terminology used in the detailed description is only for the purpose of describing embodiments of the present invention and should not be limited in any way. Unless clearly used otherwise, the singular form includes the plural form. In this description, expressions such as "comprises" or "having" are intended to indicate certain features, numbers, steps, operations, elements, parts or combinations thereof, and should not be construed to exclude the presence or possibility of one or more other features, numbers, steps, operations, elements, parts or combinations thereof other than those described.

[0046] Meanwhile, directional terms such as upper, lower, one side, and the other side are used in reference to the orientation of the disclosed drawings. Since components of embodiments of the present invention can be positioned in various orientations, directional terms are used for illustrative purposes and are not intended to be limiting.

[0047] Additionally, while terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms may be used to distinguish one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a "second component," and similarly, a second component may also be referred to as a "first component."

[0048] FIG. 1 is a drawing showing a wideband antenna according to one embodiment of the present invention.

[0049] Referring to FIG. 1, a wideband antenna (100) may include a substrate (102), a feed line (104), and a radiator (106). In one embodiment, the wideband antenna (100) may be used in a penetrating radar such as a ground-penetrating radar (GPR) or a through-the-wall radar (TWR), but is not limited thereto, and may be used in various other fields such as a medical imaging radar (MIR).

[0050] The substrate (102) can support a wideband antenna (100). A printed circuit board having a preset dielectric constant can be used as the substrate (102). In one embodiment, the substrate (102) can be formed in a square shape, but the shape of the substrate (102) is not limited thereto.

[0051] A feeding line (104) may be provided on one side of the substrate (102). The feeding line (104) may be provided to connect a feeding point at one end of the substrate (102). In one embodiment, the feeding point (P) may be provided at the center of the substrate (102).

[0052] A radiator (106) may be provided on one surface of a substrate (102). The radiator (106) may be provided connected to the end of a power supply line (104) (i.e., a power supply point). The radiator (106) may receive power from the power supply line (104) and transmit and receive signals.

[0053] The radiator (106) may be arranged symmetrically left and right with respect to the center of the substrate (102). In one embodiment, the radiator (106) may be a Vivaldi antenna of an anti-podal type. The radiator (106) may include a closed surface formed by a first curve (S1) having a first exponential function shape and a second curve (S2) having a second exponential function shape based on a feeding point. At this time, the starting points of the first curve and the second curve are the same as the feeding point, and the end points of the first curve and the second curve are also the same. In FIG. 2, the end points of the first curve and the second curve are illustrated near the left and right corners of the upper end of the substrate (102), but are not limited thereto. Here, the first curve (S1) may form an upper curve of the closed surface forming the radiator (106), and the second curve (S2) may form a lower curve of the closed surface.

[0054] Meanwhile, the parameters involved in the slope components of the first curve (S1) and the second curve (S2) can be defined as follows. The first slope parameter (n1) is a parameter involved in the slope at the starting point of the first curve. The second slope parameter (n2) is a parameter involved in the slope at the ending point of the first curve. The third slope parameter (n3) is a parameter involved in the slope at the starting point of the second curve. The fourth slope parameter (n4) is a parameter involved in the slope at the ending point of the second curve.

[0055] And, the length of the radiator (106) in the horizontal direction (x-axis direction) based on the feeding point on the closed surface (P) of the radiator (106) is the horizontal length (x base ) is defined as the length of the radiator (106) in the vertical direction (y-axis direction) based on the power supply point, and the vertical length (y base ) can be defined as.

[0056] Then, when the horizontal direction is the x-axis and the vertical direction is the y-axis based on the power supply point (i.e., the power supply point is the origin), the first curve (S1) can be expressed by the following mathematical equation 1.

[0057] (Equation 1)

[0058]

[0059]

[0060] Here, is. The horizontal length (x) of the radiator (106) base ) and vertical length (y base ) is fixed, the first curve (S1) is determined by the first slope parameter (n1) and the second slope parameter (n2).

[0061] And, the second curve (S2) of the radiator (106) can be expressed by the following mathematical expression 2.

[0062] (Equation 2)

[0063]

[0064]

[0065] Here, is. The horizontal length (x) of the radiator (106) base ) and vertical length (y base ) is fixed, the second curve (S2) is determined by the third slope parameter (n3) and the fourth slope parameter (n4).

[0066] That is, the shape of the closed surface (P) of the radiator (106) can be determined by the first slope parameter (n1), the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4). In addition, the radiation characteristics of the wideband antenna (100) change depending on the shape of the closed surface of the radiator (106).

[0067] Here, the optimization value that optimizes the radiation characteristics of the wideband antenna (100) can be calculated for each of the first slope parameter (n1), the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4). For example, when calculating the optimization value for the first slope parameter (n1), the radiation characteristics of the wideband antenna (100) can be checked by changing the value of the first slope parameter (n1) while fixing the remaining slope parameters (i.e., n2 to n4) to preset values, thereby determining the value of the first slope parameter (n1) at which the radiation characteristics of the wideband antenna (100) are the best. In addition, the optimal values ​​can be determined for the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4) by changing the values ​​of the corresponding slope parameters while fixing the remaining slope parameters to preset values, thereby checking the radiation characteristics of the wideband antenna (100).

[0068] Fig. 2 is a graph comparing antenna characteristics when the closed-surface shape of the radiator is changed by changing the slope parameter in one embodiment of the present invention. Fig. 2 shows the reflection coefficient (Fig. 2 (a)) and input impedance (Fig. 2 (b)) when the closed-surface shape of the radiator is changed, such as Case 1, Case 2, and Case 3. Here, Case 1 and Case 2 are cases where the first curve (S1) is changed, and Case 2 and Case 3 are cases where the second curve (S2) is changed.

[0069] As shown in Fig. 2, by changing the slope parameters of the first curve (S1) and the second curve (S2) to change the closed surface shape of the radiator (106), it can be seen that the reflection coefficient and input impedance of the antenna (100) change. In Fig. 2, it can be seen that Case 3 has the best characteristics of the antenna (100).

[0070] FIG. 3 is a block diagram illustrating a computing environment (10) including a computing device suitable for use in exemplary embodiments. In the illustrated embodiment, each component may have different functions and capabilities other than those described below, and may include additional components other than those described below.

[0071] The illustrated computing environment (10) includes a computing device (12). In one embodiment, the computing device (12) may be a device for designing a wideband antenna. The computing device (12) may include a simulation for designing a wideband antenna. For example, the computing device (12) may perform antenna design simulation using HFSS (High Frequency Structure Simulator).

[0072] A computing device (12) includes at least one processor (14), a computer-readable storage medium (16), and a communication bus (18). The processor (14) may cause the computing device (12) to operate according to the exemplary embodiments mentioned above. For example, the processor (14) may execute one or more programs stored in the computer-readable storage medium (16). The one or more programs may include one or more computer-executable instructions, which, when executed by the processor (14), may be configured to cause the computing device (12) to perform operations according to the exemplary embodiments.

[0073] A computer-readable storage medium (16) is configured to store computer-executable instructions or program code, program data, and / or other suitable forms of information. A program (20) stored in the computer-readable storage medium (16) includes a set of instructions executable by the processor (14). In one embodiment, the computer-readable storage medium (16) may be a memory (volatile memory such as random access memory, non-volatile memory, or a suitable combination thereof), one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, any other form of storage medium that is accessible by the computing device (12) and capable of storing desired information, or a suitable combination thereof.

[0074] A communication bus (18) interconnects various other components of the computing device (12), including the processor (14) and computer-readable storage media (16).

[0075] The computing device (12) may also include one or more input / output interfaces (22) that provide interfaces for one or more input / output devices (24) and one or more network communication interfaces (26). The input / output interfaces (22) and the network communication interfaces (26) are connected to the communication bus (18). The input / output devices (24) may be connected to other components of the computing device (12) via the input / output interfaces (22). Exemplary input / output devices (24) may include input devices such as pointing devices (such as a mouse or a trackpad), a keyboard, a touch input device (such as a touchpad or a touchscreen), a voice or sound input device, various types of sensor devices and / or photographing devices, and / or output devices such as display devices, printers, speakers and / or network cards. The exemplary input / output devices (24) may be included within the computing device (12) as a component constituting the computing device (12), or may be connected to the computing device (12) as a separate device distinct from the computing device (12).

[0076] Figure 4 is a flowchart illustrating a method for designing a wideband antenna according to one embodiment of the present invention. While the illustrated flowchart depicts the method as divided into multiple steps, at least some of the steps may be performed in a different order, combined with other steps and performed together, omitted, divided into sub-steps, or performed with one or more additional steps not illustrated.

[0077] Referring to FIG. 4, the computing device (12) can determine the first curve (S1) and the second curve (S2) of the wideband antenna (100) by selecting the value of the first slope parameter (n1) from a preset range while fixing the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4) among the first slope parameter (n1), the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4) of the wideband antenna (100) to preset values ​​(S 101). At this time, the shape of the radiator (106) is determined due to the first curve (S1) and the second curve (S2).

[0078] Next, the computing device (12) can calculate the reflection pulse in the time domain of the wideband antenna (100) (S 103). That is, the computing device (12) can calculate the reflection pulse in the time domain for the wideband antenna (100) in which the first curve (S1) and the second curve (S2) are determined by the first slope parameter (n1) to the fourth slope parameter (n4). The computing device (12) can calculate the reflection pulse in the time domain of the wideband antenna (100) based on the reflection coefficient of the wideband antenna (100) and the input signal.

[0079] Specifically, the computing device (12) can calculate the reflection coefficient of the wideband antenna (100). In addition, the computing device (12) can Fourier transform the input signal (i.e., the first-order differentiated Gaussian pulse) of the wideband antenna (100). The computing device (12) can multiply the reflection coefficient of the wideband antenna (100) and the Fourier-transformed input signal and inversely Fourier transform it to calculate the time-domain reflection pulse of the wideband antenna (100). The computing device (12) can calculate the time-domain reflection pulse of the wideband antenna (100) through the following mathematical expression 3. ) can be produced.

[0080] (Equation 3)

[0081]

[0082] : Reflection coefficient of wideband antenna

[0083] : Input signal of wideband antenna

[0084] FT: Fourier transform

[0085] IFT: Inverse Fourier Transform

[0086] Next, the computing device (12) can calculate the first evaluation factor value and the second evaluation factor value for performance evaluation of the wideband antenna (100) from the time domain reflection pulse of the wideband antenna (100) (S 105).

[0087] Here, the first evaluation factor may be the peak-to-peak value of the reflected pulse at the feeding point of the wideband antenna (100) (i.e., the starting point where the first curve and the second curve meet). That is, the first evaluation factor may be the peak-to-peak value of the signal reflected at the feeding point of the wideband antenna (100). Peak-to-peak may mean the difference between the highest value and the lowest value in the signal waveform. In addition, the second evaluation factor may be the peak-to-peak value of the reflected pulse at the end of the radiator (106) of the wideband antenna (100) (i.e., the end point where the first curve and the second curve meet).

[0088] Fig. 5 is a graph showing a reflected pulse in the time domain of a wideband antenna (100) in one embodiment of the present invention. Fig. 5 shows the reflected pulse in the time domain for each of the cases where the radiator shape is Case 1, Case 2, and Case 3.

[0089] Referring to FIG. 5, the first evaluation factor is the peak-to-peak (V) of the reflected pulse at the feeding point of the wideband antenna (100). pp,port refl.) is. Here, since Fig. 5 is a reflection pulse in the time domain, the reflection pulse at the feeding point (reflection pulse near the point where the input signal is input) can be easily detected. In addition, the second evaluation factor is the peak-to-peak (V) of the reflection pulse at the end of the radiator (106) of the wideband antenna (100). pp,endrefl. ), it can be calculated by extracting the reflection pulse at a point in time when a certain amount of time has passed since the reflection pulse at the power supply.

[0090] Next, the computing device (12) can produce a time-domain radiation pulse of the wideband antenna (100) (S 107). The computing device (12) can produce a time-domain radiation pulse of the wideband antenna (100) based on the reflection coefficient of the wideband antenna (100), the input signal of the wideband antenna (100), and the electric field component (frequency domain) of the far field of the wideband antenna (100).

[0091] The computing device (12) is configured to generate a time-domain radiated pulse of the wideband antenna (100) using the following mathematical expression 4. ) can be produced.

[0092] (Equation 4)

[0093]

[0094] :Electric field components in the far field of a wideband antenna

[0095] Next, the computing device (12) can calculate the third evaluation factor value and the fourth evaluation factor value for performance evaluation of the wideband antenna (100) from the time domain radiation pulse of the wideband antenna (100) (S 109).

[0096] Here, the third evaluation factor may be the peak-to-peak value of the main pulse of the signal radiated from the wideband antenna (100). That is, the third evaluation factor may be the peak-to-peak value of the main pulse of the signal radiated when the wideband antenna (100) radiates the signal into the air. In addition, the fourth evaluation factor may be the peak-to-peak value of the signal (i.e., the ringing signal) reflected from the radiator (106) of the wideband antenna (100) and then re-radiated into the air.

[0097] Fig. 6 is a graph showing a time-domain radiation pulse of a wideband antenna (100) in one embodiment of the present invention. Fig. 6 shows the time-domain radiation pulse for each of the cases where the radiator shape is Case 1, Case 2, and Case 3.

[0098] Referring to FIG. 6, the third evaluation factor is the peak-to-peak value (V) of the main pulse of the signal radiated from the wideband antenna (100). pp,rad ) can be. Here, Fig. 6 is a time-domain radiation pulse, and the main pulse of the radiation signal has the largest signal size among the radiation pulses, so the main pulse of the radiation signal can be easily detected.

[0099] Additionally, the fourth evaluation factor is the peak-to-peak value (V) of the signal (i.e., ringing signal) that is reflected from the radiator (106) of the wideband antenna (100) and then re-radiated into the air. pp,re-rad ) can be. Here, the ringing signal is a signal that occurs after the main pulse of the radiation signal and forms a shaking pattern with a signal of a smaller size than the main pulse, so it can be easily detected.

[0100] Next, the computing device (12) is the first evaluation element (V pp,port refl. ), second evaluation factor (V pp,endrefl ), the third evaluation factor (V pp,rad ), and the fourth evaluation factor (V pp,re-rad) can be used to evaluate the radiation performance of the wideband antenna (100) (S 111).

[0101] Here, the computing device (12) can evaluate the radiation performance of the wideband antenna (100) through a preset evaluation index. In one embodiment, the computing device (12) can evaluate the first evaluation factor (V pp,port refl. ), second evaluation factor (V pp,endrefl ), and the fourth evaluation factor (V pp,re-rad ) indicates that the radiation performance of the wideband antenna (100) is better as the value of the third evaluation factor (V pp,rad ) can be set to indicate that the larger the value, the better the radiation performance of the wideband antenna (100). The computing device (12) can set the evaluation index (Evaluation Factor: EF) through the following mathematical expression 5.

[0102] (Equation 5)

[0103] Evaluation Criteria =

[0104] Through this process, the computing device (12) can evaluate the radiation performance of the wideband antenna (100) when the value of the first slope parameter (n1) is selected from a preset range while fixing the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4) to preset values.

[0105] Next, the computing device (12) can extract the value of the first slope parameter (n1) that best improves the radiation performance of the wideband antenna (100) as an optimal value by changing the value of the first slope parameter (n1) within a preset range while fixing the second slope parameter (n2), the third slope parameter (n3), and the fourth slope parameter (n4) to preset values ​​(S 113).

[0106] For example, the computing device (12) can evaluate the radiation performance of the wideband antenna (100) by changing the value of the first slope parameter (n1) (for example, changing from n1 = 2 to n1 = 6) while fixing the second slope parameter (n2) to the fourth slope parameter (n4) to preset values, and extract the value of the first slope parameter (n1) that best improves the radiation performance of the wideband antenna (100) as the optimal first slope parameter (n1) value.

[0107] FIG. 7 is a diagram showing each evaluation factor and evaluation index (EF) of a wideband antenna (100) according to changes in the first slope parameter (n1) value in one embodiment of the present invention. Here, the first slope parameter (n1) value was measured while changing from n1 = 2 to n1 = 6, and the remaining slope parameters used fixed values. As can be seen in FIG. 7, the case where n1 = 4 has the best evaluation index (EF) of 975.0522.

[0108] Meanwhile, the computing device (12) can extract the optimal second slope parameter (n2) to fourth slope parameter (n4) values ​​that best improve the radiation performance of the wideband antenna (100) in the same manner for the second slope parameter (n2) to fourth slope parameter (n4).

[0109] Fig. 8 is a diagram showing a wideband antenna shape when the first slope parameter (n1) to the fourth slope parameter (n4) are at optimal values ​​in one embodiment of the present invention. In Fig. 8, the first slope parameter (n1) is set to n1 = 4, the second slope parameter (n2) is set to n2 = 1, the third slope parameter (n3) is set to n3 = 1, and the fourth slope parameter (n4) is set to n4 = 9.

[0110] According to the disclosed embodiment, a wideband antenna can be designed by well reflecting the characteristics of an input signal of the wideband antenna in the time domain, thereby optimizing the radiation performance of the wideband antenna.

[0111] FIG. 9 is a drawing showing a wideband antenna according to a second embodiment of the present invention.

[0112] Referring to FIG. 9, a wideband antenna (100) may include a substrate (102), a feed line (104), and a radiator (106). The radiator (106) may have a shape that applies optimal slope parameter values.

[0113] Here, one or more slots (111) may be formed in the radiator (106). The slots (111) may be provided in a form in which a portion of the radiator (106) is removed. The slots (111) may be provided along a certain direction in the radiator (106). In one embodiment, the slots (111) may be provided along a vertical direction (y-axis direction). The slots (111) are provided along the radiator (106) from one end to the other end, thereby separating the radiator (106) into a plurality of parts.

[0114] In addition, when a plurality of slots (111) are formed, the slots (111) may be provided at a constant interval in the horizontal direction (x-axis direction) from the radiator (106). At this time, when N slots (111) are formed, the radiator (106) may be separated into N+1 parts. For example, as illustrated in FIG. 9, when three slots (111) are formed, the radiator (106) may be separated into four parts.

[0115] A component (113) having an impedance may be inserted into each slot (111). Hereinafter, the component having an impedance may be referred to as an impedance component (113). The impedance component (113) may be provided to connect adjacent parts of the radiator (106) in the corresponding slot (111). That is, the impedance component (113) may be provided to connect parts of the radiator (106) separated by the slot (111). A plurality of impedance components (113) may be inserted into the slot (111) while being spaced apart from each other.

[0116] In one embodiment, the impedance component (113) may be a chip resistor, but is not limited thereto, and a passive element such as an inductor or capacitor may also be used. In addition, a sheet having a resistance component may be used as the impedance component (113) and inserted into the slot (111), but is not limited thereto, and the surface resistance of the slot (111) itself may be used as the impedance component (113). That is, during the process of forming the slot (111), the slot (111) itself may be provided to have an impedance component.

[0117] Here, when there are multiple slots (111), an impedance component (113) can be inserted into each slot (111). When the total impedance value of the impedance components (113) inserted into the slots (111) of the radiator (106) is determined, the impedance values ​​of the impedance components (113) inserted into each slot (111) can be set differently.

[0118] In one embodiment, the impedance value of the impedance component (113) inserted into the slot (111) may be determined based on the position of the corresponding slot (111) and the total number of slots (111). Here, the position of the slot (111) may indicate which slot (i.e., which slot is located at a certain distance from the feeding point) it corresponds to when the slots (111) are formed at a certain distance in the horizontal direction in the radiator (106). In one embodiment, the farther a slot is located from the feeding point, the greater the impedance value of the inserted impedance component (113).

[0119] The impedance value of the impedance component (113) inserted into each slot (111) can be determined based on the total impedance value of the impedance components (113) inserted into each slot (111), the diagonal length of the radiator (106), and the position of the corresponding slot (111) according to the total number of slots. Here, the diagonal length of the radiator (106) can mean the straight line length from the starting point to the ending point of the first curve or the second curve of the radiator (106). In addition, the total impedance value can be determined by the resonant frequency of the wideband antenna (100), etc.

[0120] The impedance value of the impedance component (113) inserted into the slot (111) can be determined by the following mathematical expression 6.

[0121] (Equation 6)

[0122]

[0123] Z i : Impedance value of the impedance component inserted into the i-th slot

[0124] Z scale : Pre-set slot impedance adjustment factor

[0125] L: diagonal length of the radiator

[0126] : Position of the i-th slot according to the total number of slots

[0127] Here, the position of the i-th slot according to the total number of slots ( ) can mean the length from the power supply point to the i-th slot. In addition, Z scale can be determined based on the total impedance value of the impedance components (113) inserted into each slot (111), the diagonal length of the radiator (106), and the total number of slots. Z scale can be set by the following mathematical formula 7.

[0128] (Equation 7)

[0129]

[0130] Z total : Total impedance value of the impedance components inserted into each slot

[0131] N: Total number of slots

[0132] For example, the total number of slots provided in the radiator (106) is 3 (N=3), and the total impedance value of the impedance components inserted into each slot is 180Ω (Z total = 180), and if the diagonal length of the radiator (106) is 56.5685 mm (L = 56.5685), the impedance values ​​(Z) of the impedance components inserted into the first slot, the second slot, and the third slot 1, Z2, Z3) can be calculated as follows.

[0133]

[0134] When the impedance value of the impedance component (113) to be inserted into each slot (111) is determined, a plurality of impedance components (113) can be inserted into the corresponding slot (111) while being spaced apart from each other, and at this time, the sum of the impedance values ​​of the plurality of impedance components (113) can be made to be the determined impedance value. In this case, the impedance component is inserted into the corresponding slot (111) in a discretized form.

[0135] In this way, when the impedance component (113) is inserted into the slot (111), the flow of current in the radiator (106) can be controlled by the impedance component (113). Specifically, when current flows in the radiator (106), the current is absorbed or attenuated by the impedance component (113), so that the size of the current reflected from the radiator (106) can be minimized, thereby reducing the electrical size of the radiator (106) so that it can operate well in a low-frequency band even with a limited size of the wideband antenna (100).

[0136] Figures 10 and 11 are graphs showing the reflection coefficient and VSWR of a wideband antenna in a second embodiment of the present invention, respectively, when a slot is formed in the radiator and an impedance component is inserted, and when it is not. Here, the case where a slot (111) is formed in the radiator (106) and an impedance component (113) is inserted is indicated as "RLAVA," and the case where it is not is indicated as "CAVA." In addition, "simul" indicates a simulation result, and "meas" indicates a measured result.

[0137] Referring to FIGS. 10 and 11, it can be seen that when a slot (111) is formed in the radiator (106) and an impedance component (113) is inserted (RLAVA(simul, meas)), the performance of the reflection coefficient and VSWR in the low frequency band of 0.8 to 1.8 GHz is superior to that when the slot (111) is formed in the radiator (106) and an impedance component (113) is inserted (CAVA(simul, meas)).

[0138] FIG. 12 and FIG. 13 are graphs showing the time-domain reflection pulse and radiation pulse of a wideband antenna (100) in the case where a slot is formed in the radiator and an impedance component is inserted, and in the case where it is not, respectively, in the second embodiment of the present invention. Here, the case where a slot (111) is formed in the radiator (106) and an impedance component (113) is inserted is indicated as "RLAVA," and the case where it is not is indicated as "CAVA." In addition, "simul" indicates a simulation result, and "meas" indicates a measured result.

[0139] Referring to Fig. 12, the first evaluation factor (V) is compared with the case where a slot (111) is formed in the radiator (106) and an impedance component (113) is inserted (RLAVA(simul, meas)) compared with the case where it is not (CAVA(simul, meas)). pp,port refl. ) and the second evaluation factor (V pp,endrefl ) is small, it can be seen that the radiation performance of the wideband antenna (100) is improved.

[0140] Referring to Fig. 13, the third evaluation factor (V) is compared to the case where a slot (111) is formed in the radiator (106) and an impedance component (113) is inserted (RLAVA(simul, meas)) compared to the case where it is not (CAVA(simul, meas)). pp,rad ) has somewhat decreased in value, but the fourth evaluation factor (V pp,re-rad ) is further reduced, and it can be seen that the radiation performance of the wideband antenna (100) is improved.

[0141] Meanwhile, additional slots in a circular or oval shape may be formed in each part of the radiator (106) of the wideband antenna (100). At this time, the additional slots may be provided adjacent to the impedance components (113) in each part of the radiator (106). That is, when a plurality of impedance components (113) are provided spaced apart from the slots (111), the additional slots may be provided near each impedance component (113). The additional slots may also be provided at regular intervals along the edge of the radiator (106).

[0142] In this case, the current flow in the radiator (106) can be distributed throughout the radiator (106) by the additional slot and impedance component (113), and the current flow is guided relatively toward the impedance component (113) by bypassing along the additional slot, thereby further reducing the size of the current reflected from the radiator (106), thereby improving the radiation performance of the wideband antenna (100).

[0143] While representative embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that various modifications to the above-described embodiments are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims set forth below but also by equivalents thereof.

Claims

1. Substrate; One or more radiators provided on one surface of the above substrate; One or more slots provided from one end to the other along the first direction in the above radiator to separate the radiator into a plurality of parts; and A wideband antenna comprising an impedance component provided in the above slot.

2. In claim 1, The above impedance components are, A broadband antenna, which is provided by connecting parts of the radiator separated by the slot in the slot.

3. In claim 1, The above slots are provided in multiple numbers spaced apart from each other in a second direction perpendicular to the first direction in the above radiator, A wideband antenna, wherein the above impedance components are inserted into a plurality of respective slots.

4. In claim 3, A wideband antenna in which the impedance values ​​of impedance components inserted into each slot are set differently depending on the position of the slot based on the power supply point provided on the above substrate.

5. In claim 3, The above radiator is, A wideband antenna comprising a closed surface formed by a first curve having a first exponential function shape based on a feeding point provided on the substrate and a second curve having a second exponential function shape based on the feeding point.

6. In claim 5, The impedance value of the impedance component inserted into each of the above slots is A wideband antenna, the total impedance value of the impedance components inserted into each slot, the diagonal length of the radiator, and the position of the corresponding slot based on the total number of slots.

7. In claim 6, A wideband antenna in which the impedance value of the impedance component inserted into the above slot is set using the mathematical formula below. (mathematical formula) Z i : Impedance value of the impedance component inserted into the i-th slot Z scale : Pre-set slot impedance adjustment factor L: diagonal length of the radiator : Position of the i-th slot according to the total number of slots 8. In claim 7, The above slot impedance adjustment factor (Z scale ) is a wideband antenna determined by the following mathematical formula. (mathematical formula) Z total : Total impedance value of the impedance components inserted into each slot N: Total number of slots 9. In claim 1, The above broadband antenna, A broadband antenna further comprising one or more additional slots formed in each part of the radiator.

10. In claim 9, The above additional slots are, A broadband antenna, wherein each part of the radiator is provided adjacent to the impedance component so that the current flow from the radiator is directed toward the impedance component by detouring along the additional slot.

11. In claim 1, The above radiator is, It includes a closed surface formed by a first curve having a first exponential function shape based on a power supply point provided on the substrate and a second curve having a second exponential function shape based on the power supply point, The first curve is determined by a first slope parameter involved in the slope at the starting point of the first curve and a second slope parameter involved in the slope at the ending point of the first curve, A wideband antenna, wherein the second curve is determined based on a third slope parameter involved in the slope at the starting point of the second curve and a fourth slope parameter involved in the slope at the ending point of the second curve.

12. In claim 11, The first slope parameter to the fourth slope parameter are, A wideband antenna, wherein the performance of the wideband antenna is determined based on values ​​of evaluation factors calculated based on a time-domain reflection pulse of the wideband antenna and values ​​of evaluation factors calculated based on a time-domain radiation pulse of the wideband antenna.

13. Substrate; A power supply point provided on the above substrate; A radiator provided symmetrically on one side of the substrate with respect to the power supply point; One or more slots provided from one end to the other along the vertical direction in the above radiator to separate the radiator into a plurality of parts; and A wideband antenna comprising an impedance component provided in the above slot.

14. A radar having a wideband antenna as described in claim 1.

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