JP2005260875A - Surface mounted patch antenna and its mounting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface mounted patch antenna having a feeding portion at a predetermined position in an x direction and a y direction from a center position of a radiation electrode, capable of performing surface mount without making a feeding pin to pass through a mounting substrate etc. <P>SOLUTION: The radiation electrode 2 is provided to a surface which is a plane of a dielectric substrate 1, and a ground electrode 5 is provided at a back surface which is opposing to the plane of the dielectric substrate 1. One end portion 3a of the feeding pin 3 is connected to the radiation electrode 2, and the other end portion 3b is extracted to the back surface side through a through hole 1a provided on the dielectric substrate 1. At the back surface side of the dielectric substrate 1 of this through hole 1a, a recess portion 1b having the mostly same center as the through hole 1a and an inner circumference larger than a diameter of the through hole 1a is to be formed. The other end portion 3b of the feeding pin 3 is to be formed on the nearly same plane as an exposed surface of the ground electrode 5 to be provided on the back surface of the dielectric substrate 1, and is to be formed as the configuration to be directly mounted on the surface of the mounting substrate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface-mount type patch antenna in which a radiation electrode is formed with an electrical length of ½ wavelength in a frequency band of a signal to be transmitted and received on a dielectric substrate surface and operates in a patch mode and a mounting method thereof. More specifically, when a patch antenna is mounted on a mounting board, it is not a structure in which the power feed pin penetrates the mounting board and is connected on the back surface of the mounting board, but a surface mounting type in which the power feeding pin can be connected only on the mounting board surface. The present invention relates to a patch antenna and a mounting method thereof.

For example, the patch antenna has an antenna radiation electrode 22 formed of a conductor film on one surface of one side of a dielectric substrate 21, as shown in FIGS. Is approximately λ / (2ε _r ^1/2 ) (λ is the wavelength of the transmitting / receiving frequency band, ε _r is the dielectric constant of the dielectric substrate) and is approximately square (the ratio of length to width is the gain, bandwidth, etc. The feed point 22a is provided at a position displaced from the center of the antenna radiation electrode 22 in the x-axis direction and the y-axis direction, respectively, and the feed pin 23 is connected to the feed point 22a. The other end of the power supply pin 23 is connected to the power supply circuit. In the patch antenna, the central portion of the antenna radiation electrode 22 is the maximum point of current and the current is minimum, that is, the voltage is maximum at the end portion. Therefore, both the x-axis direction and the y-axis direction are displaced from the center portion. There is an impedance of about 50Ω, which is the impedance on the power supply side, and the power supply point 22a is formed at that portion. A conductive film serving as the ground electrode 25 is formed on the back surface of the dielectric substrate 21. Note that the power supply pin 23 is led away from the ground electrode 25 through the through hole 21 a of the dielectric substrate 21 and the through hole 25 a of the ground electrode 25.

On the other hand, as a type that is surface-mounted with a patch antenna, for example, a perspective view seen from the front side and an explanatory view of the bottom surface thereof are shown in FIG. It is also conceivable that the power supply portion 44 is formed on the rear surface of the dielectric substrate 41 by being drawn out from the dielectric substrate 41 to the rear surface through the side surface of the dielectric substrate 41 and can be directly soldered to the mounting substrate with a reflow furnace or the like. (For example, refer to Patent Document 1). That is, since it is for linearly polarized waves, the direction of the electric field is one direction, and the length of one direction has an electrical length of approximately ½ wavelength, and power is supplied at a predetermined distance from the center. Since impedance matching can be achieved and the position in the width direction, which is a direction orthogonal to that direction, is not so constrained, there is no problem even if power is supplied from the side of the radiation electrode, The feed line 43 can be pulled out. In FIG. 11, 45 is a ground electrode.
JP 2002-314325 A

  As described above, since the conventional circularly polarized patch antenna has electric field components in the orthogonal x and y directions, the position of a predetermined impedance at a certain distance from the center position in both the x and y directions. It is necessary to connect the power supply pin 23 to the power supply pin 23, and the power supply pin 23 must be led out to the back surface side of the dielectric substrate 21 through the through hole 21 a that penetrates the dielectric substrate 21. Therefore, even when mounted on the mounting board, as shown in FIG. 10C, a through hole 26a is formed in the mounting board 26, and the power supply pin 23 is passed through the through hole 26a of the mounting board 26 so as to be mounted. Soldering 27 must be done on the back side. As a result, it is difficult to adopt a joining method of mounting on a mounting substrate and performing batch soldering in a reflow furnace or the like, which complicates the mounting operation and causes an increase in cost. Furthermore, if the mounting board is penetrated and soldered on the back side, a protrusion of about d = 1.5mm is created on the back side of the mounting board, which saves space and hinders downsizing, and mounts components on the back side of the mounting board. The space to do is also restricted.

  On the other hand, in recent years, patch antennas have been mounted on very small and inexpensive products such as cellular phones from the viewpoint of improving antenna performance. When patch antennas are used, the components mounted on the mounting board are highly integrated. However, there is a problem that it is impossible to meet the needs. In order to solve this problem, it is conceivable to reduce the thickness of the dielectric substrate or shorten the thickness d of the protruding portion of the feed pin to 0.5 mm or less. In addition, there is a problem that the width of the power supply pin is shortened, and if the protruding portion of the power supply pin is shortened, the reliability of soldering is reduced. It cannot meet the demand to do.

  The present invention has been made to solve such a problem, and is a patch antenna having a power feeding portion at a predetermined position in both the x and y directions from the center position of the radiation electrode. An object of the present invention is to provide a surface mount type patch antenna that can be surface mounted without penetrating a feed pin.

  Another object of the present invention is to provide a surface-mounted patch that reliably connects the power supply pins to the mounting substrate even when the patch antenna having the power supply pins is surface-mounted on a mounting substrate or the like, and does not reduce the connection reliability. An object is to provide an antenna mounting method.

  A surface-mounted patch antenna according to the present invention includes a dielectric substrate, a radiation electrode provided on a surface that is one surface of the dielectric substrate, and a ground electrode provided on a back surface that is a surface facing the one surface of the dielectric substrate. A patch antenna having one end connected to the radiation electrode and the other end fed to the back surface through a through hole provided in the dielectric substrate, the patch antenna having the through hole A recess is formed on the back side of the dielectric substrate that is substantially concentric with the through hole and has an inner circumference larger than the diameter of the through hole, and the other end of the power supply pin is provided on the back side of the dielectric substrate. It is formed in a structure that is substantially flush with the exposed surface of the ground electrode and can be directly mounted on the surface of the mounting substrate.

  Here, “a concave portion that is substantially concentric with the through-hole and has an inner circumference larger than the diameter of the through-hole” means that the concave portion does not have to have a circular cross-sectional shape, and the respective central portions are located at substantially the same position. This means that the recess is formed large.

  A flange portion that facilitates connection with the mounting board is formed at the other end of the power supply pin, so that when connecting to the mounting board by soldering or the like, stable connection can be achieved. , Connection reliability is improved. Here, the flange portion means a flat portion having an outer shape larger than the thickness of the power supply pin.

  Another embodiment of the surface-mounted patch antenna according to the present invention includes a dielectric substrate, a radiation electrode provided on a surface that is one surface of the dielectric substrate, and a back surface that is a surface facing the one surface of the dielectric substrate. A through hole is formed in a portion of the dielectric substrate corresponding to a position where the power supply pin of the radiation electrode is connected and a position where the power supply pin is connected. A recess having an inner circumference larger than the diameter of the through hole is formed on the back surface side of the dielectric substrate, and the power supply pin provided on the surface of the mounting substrate is formed in the through hole. It is formed in a structure that can be inserted and connected to the radiation electrode.

  Still another embodiment of the surface-mounted patch antenna according to the present invention includes a dielectric substrate, a radiation electrode provided on the surface that is one surface of the dielectric substrate, and a back surface that is the surface facing the one surface of the dielectric substrate. A patch antenna having a ground electrode provided at one end and a feed pin that is connected to the radiation electrode at one end and led to the back side through a through hole provided in the dielectric substrate at the other end; The power supply pin is formed of a movable pin whose other end can be changed in protrusion length via a spring, and the tip of the movable pin is provided so as to protrude from the exposed surface of the ground electrode. By being pressed onto the mounting substrate by the moving force of the movable pin when fixed to the surface, the surface can be mounted on the surface of the mounting substrate.

  A concave portion having an inner circumference substantially concentric with the through hole and larger than the diameter of the through hole is formed on the back surface side of the dielectric substrate of the through hole, and is inserted into the concave portion on the outer circumference of the power feed pin. A ridge is formed, and one end of the power supply pin can be connected and fixed to the radiation electrode with the ridge as a reference. By doing so, it is easy to position the power supply pin, and it is easy to easily connect and fix the power supply pin and the radiation electrode with a fixed length and without a jig in a reflow furnace or the like.

  The surface-mounted antenna mounting method according to the present invention includes: (a) a portion where a radiation electrode is formed on one surface of a dielectric substrate, a ground electrode is formed on the other surface, and a feed pin connected to the radiation electrode is provided; An assembly of a patch antenna dielectric substrate having through holes formed in the radiation electrode, the dielectric substrate, and the ground electrode and an electrode portion is formed, and (b) power is supplied to the power supply terminal on the surface of the mounting substrate on which the patch antenna is mounted. (C) mounting the patch antenna assembly on the surface of the mounting substrate so that the feed pin penetrates the through hole of the patch antenna assembly; The tip of the power supply pin is electrically connected to the radiation electrode.

  According to one embodiment of the present invention, the other end of the feed pin whose one end is connected to a predetermined position of the radiation electrode constituting the patch antenna is not formed so long as to penetrate the mounting substrate. The end is formed so as to be substantially flush with the exposed surface of the ground electrode provided on the back surface of the dielectric substrate, and the inner circumference larger than the diameter of the through hole is formed in the through hole portion that penetrates the power feed pin near the other end. Therefore, the other end of the power supply pin can be fixed directly on the surface of the mounting substrate by soldering or the like, and can be easily mounted only on the surface of the mounting substrate. That is, as a result of extensive studies by the present inventors, even when a concave portion that secures a space for soldering is formed on the back surface of the dielectric substrate, the size of the concave portion is a diameter (the shape of the concave portion is circular). It is not limited, but if it is about 10 mm or less (average size), it is found that the antenna characteristics VSWR and radiation characteristics are hardly affected, and it is necessary to connect to a predetermined place inside the radiation electrode. It has been found that even a power supply pin having a surface can be surface mounted with the other end aligned with the position of the exposed surface of the ground electrode.

  In addition, by forming the other end of the power supply pin with a movable pin, it can be brought into contact with the power supply part of the mounting substrate only by contact with a movable force without being fixed to the surface of the mounting substrate by soldering or the like. It is possible to perform surface mounting without penetrating the mounting substrate. In this case, since it is not necessary to perform soldering or the like, surface mounting can be performed with only the through hole without forming a recess in the dielectric substrate. However, as described above, since a small concave portion has little influence on characteristics, by forming a concave portion and forming a flange on the outer periphery of the movable pin, a feeding pin having a radiation electrode and a movable pin Can be connected easily and reliably.

  In addition, the power supply pins are fixed in advance on the mounting board side, and only the through holes are formed in the portions where the power supply pins of the patch antenna are provided, and the dielectric, radiation electrode, and ground electrode without the power supply pins are formed. By mounting the assembly of the dielectric substrate and the electrode portion, it can be mounted on the mounting substrate. In this case, as an assembly for the patch antenna, a portion of the patch antenna other than the feed pin is formed, and the feed pin portion is formed with only a through hole. Also in this case, by forming a recess having an inner circumference larger than the diameter of the through hole on the back surface of the dielectric substrate, when fixing the power supply pin upright on the mounting substrate, the fixed portion is larger than the thickness of the power supply pin. Although the possibility of becoming large is large, since there is a recess, it can be absorbed by the recess.

  With such a configuration, even in a patch antenna in which a feeding portion is formed inside the radiation electrode in both the x-direction and the y-direction instead of the end portion of the radiation electrode, the feeding pin is connected to the through hole of the mounting substrate. Can be surface-mounted without being stretched to be inserted into the board, no protrusion is formed on the back surface of the mounting board, can achieve a low profile, and high-density components can also be mounted on the back surface of the mounting board And miniaturization of the entire mounting board can be achieved. Moreover, it can be connected simply by assembling and flowing in a solder reflow furnace or the like, and assembling to a mounting board can be performed very easily. As a result, even a highly miniaturized electrical device such as a mobile phone can use a high-performance patch antenna, and can be built in a high-performance antenna that is small and inexpensive. it can.

  When the patch antenna is surface-mounted, the other end portion of the power supply pin connected to the mounting substrate is completely hidden by the dielectric substrate or the radiation electrode and the adhesion state cannot be confirmed. According to the method, the power supply pin is first fixed to the surface of the mounting substrate, and then the assembly of the dielectric substrate and the electrode portion is inserted into the power supply pin, and the one end of the power supply pin and the power supply portion of the radiation electrode are connected. Since the connection is made, any connection portion of the power supply pin can be confirmed, and the reliability of the connection can be greatly improved.

  Next, the surface mount type patch antenna of the present invention will be described with reference to the drawings. The surface mount type patch antenna according to the present invention is provided with a radiation electrode 2 on a surface which is one surface of a dielectric substrate 1, as shown in FIG. A ground electrode 5 is provided on the back surface which is a surface facing one surface of the first electrode. One end 3 a of the power feed pin 3 is connected to the radiation electrode 2, and the other end 3 b is led out to the back side through a through hole 1 a provided in the dielectric substrate 1. On the back side of the dielectric substrate 1 of the through hole 1a, a recess 1b is formed which is substantially concentric with the through hole 1a and has an inner circumference larger than the diameter of the through hole 1a. 3b is substantially flush with the exposed surface of the ground electrode 5 provided on the back surface of the dielectric substrate 1, and is formed in a structure that can be directly mounted on the surface of the mounting substrate.

The dielectric substrate 1 is preferably made of ceramics having a high dielectric constant made of, for example, barium titanate (having a relative dielectric constant of about 20), from the viewpoint of miniaturizing the antenna. That is, in the case of a patch antenna, if the but one side is formed on the electrical length of approximately lambda / 2 with respect to the wavelength lambda of the signal to be transmitted and received, the physical length is the relative permittivity of the dielectric substrate and epsilon _r, It is known that it is proportional to 1 / (ε _r ) ^1/2 , and if the relative permittivity is quadrupled, the size of one side of the antenna can be halved. Therefore, the antenna can be reduced in size by using a dielectric having a high dielectric constant. The dielectric substrate 1 is preferably thicker because it can improve electrical characteristics such as band characteristics. However, if the dielectric substrate 1 is too thick, the thickness is usually about 2 to 5 mm (4 mm in the example shown in FIG. 1). Ceramics are used.

  The size of the dielectric substrate 1 may be the same as the size of the radiation electrode 2 described later, but is usually formed slightly larger than the radiation electrode 2, for example, for 1.575 GHz, the relative dielectric constant of the dielectric substrate 1 Is 20, the size of the radiation electrode 2 is 21 mm square, and the size of the dielectric substrate 1 is about 25 mm square. In addition, a through hole 1 a for penetrating a power feed pin 3 described later is formed at a predetermined location on the dielectric substrate 1. This through-hole 1a allows a power feed pin 3 to be described later to pass through, and is formed, for example, to about 1.2 mmφ. Further, in the example shown in FIG. 1, a recess 1 b is formed on the back side of the dielectric substrate 1, which is substantially concentric with the through hole 1 a and about 3.5 mmφ and about 1.5 mm deep. The recess 1b secures a space for a conductive member such as solder to be firmly fixed to the power supply pin 3 when the power supply pin 3 to be described later is connected to the mounting substrate by soldering or the like. However, the circular shape can remove the dielectric material to the minimum necessary. In addition, the concave portion 1b is not necessary in the case of electrical connection without soldering described later.

  The radiation electrode 2 is formed as a conductor film having a thickness of about 10 to 20 μm by firing a printed material having a good conductor such as silver paste. Similarly, a ground electrode 5 is formed on the back surface of the dielectric substrate 1 facing the radiation electrode 2 by providing a conductive film such as silver paste by thick film printing or the like. That is, the patch antenna is formed by providing the radiation electrode 2 and the ground electrode 5 with the dielectric substrate 1 interposed therebetween. The material of the radiation electrode 2 and the ground electrode 5 is not limited to a material formed by sintering a silver paste, and may be formed by coating a good conductor such as copper by vacuum deposition or the like and patterning. . In this case, the thickness is about 0.1 to 1 μm.

Since the radiation electrode 2 is used for circularly polarized waves, the horizontal (x direction) and vertical (y direction) lengths L are both formed in a square shape having an electrical length of approximately ½ wavelength. It need not necessarily be square. As described above, the physical length L of one side can be reduced as the relative dielectric constant of the dielectric substrate 1 increases, and when the frequency of the signal to be transmitted / received is 1.575 GHz, the relative dielectric constant is increased. When the dielectric substrate 1 having a rate ε _r of 20 is used, the length L of one side thereof can be formed with about 21 mm. The radiation electrode 2 is provided with a power feeding portion 2a at a predetermined position slightly shifted from the center portion C in both the x direction and the y direction, and a through hole for inserting a power feeding pin 3 to be described later is provided in the power feeding portion 2a. Is formed. However, the feed pin 3 may be provided so as to be connected to the back surface of the radiation electrode 2 without forming a through hole. The power feeding unit 2a is formed at a position where the impedance matches the characteristic impedance (for example, 50Ω) on the circuit side to which the power feeding unit is connected, and is provided at a position slightly deviated from the central portion C.

  In the example shown in FIG. 1, one end portion 3 a of the power supply pin 3 is connected and fixed to the through hole provided in the power supply portion 2 a by solder 6 or the like. For example, a wire rod made of brass having a thickness of about 1.2 mmφ is used for the power supply pin 3, and the other end 3 b is provided so as to be substantially flush with the exposed surface (lower surface) of the ground electrode 5. As a result, it is possible to apply cream solder etc. to the part where the power supply pin 3 such as the mounting board is connected, place this patch antenna on the mounting board, etc., and pass it through the reflow furnace etc. The substrate can be electrically connected and fixed. Since the concave portion 1b is formed on the back surface side of the dielectric substrate 1 as described above, it is easy for the solder to go up to the power supply pin 3 to form a solder fillet and to make contact with the ground electrode 5. Can be prevented.

  In the example shown in FIG. 1, the other end 3 b side of the power feed pin remains the thickness of the power feed pin 3. For example, as shown in FIG. 2, a flange ( Since the flat plate portion 3c having a diameter larger than that of the power supply pin 3 is formed, the connection with the mounting substrate can be further ensured. As shown in FIG. 3, the power supply pin 3 is first mounted on the mounting substrate. 7, the assembly 9 of the dielectric substrate 1 for the patch antenna and the electrode portion of the dielectric substrate 1 and the electrode portion of the radiation electrode 2 and the ground electrode 5 which are assembled later is connected to the through-hole 1a. A mounting method in which the parts are fitted and assembled so that the part is inserted into the power supply pin 3 can be adopted. By doing so, since the assembly 9 can be covered after the connection between the power supply pin 3 and the mounting substrate 7 is confirmed securely, the reliability of the connection of the power supply pin 3 and the non-contact with the ground electrode 5 is improved. Can be made. In this case, the inner diameter of the recess 1b was 3.5 mmφ as described above, and the size of the flange 1c was about 2.5 mmφ.

  That is, in the patch antenna mounting method shown in FIG. 3, first, as shown in FIG. 3A, the dielectric substrate 1 having the same through-holes 1a and recesses 1b as the structure shown in FIG. An assembly 9 of a dielectric substrate for a patch antenna and an electrode portion, in which a radiation electrode 2 is formed on the front surface and a ground electrode 5 is formed on the rear surface, is formed. Next, as shown in FIG. 3 (b), the power supply pin 3 is erected at a place where the power supply pin of the mounting substrate 7 is connected, and is fixedly connected by the solder 8. At this time, since the flange 3c is formed on the other end portion side of the power supply pin 3, it can stand on the mounting substrate 7 as it is and soldered in a reflow furnace or the like, and can be soldered very easily. At the same time, it is possible to confirm whether the soldered state and the lateral spread are too large and there is a possibility of contact with the ground electrode 5. Thereafter, as shown in FIG. 3 (c), the patch antenna is directly attached to the mounting substrate 7 by covering the assembly 9 and fixing the tip 3a of the feed pin 3 to the radiation electrode 2 by the solder 6. Can be installed.

  FIG. 6 and FIG. 7 show the results of examining the VSWR and the radiation characteristics of the patch antenna mounted on the mounting board by the mounting method shown in FIG. That is, according to the present invention, not only the through-hole 1a but also the recess 1b is formed on the back surface side of the dielectric substrate 1, but as shown in FIG. With VSWR, there is almost no measurement error of about 1.52 of the conventional structure, and the radiation characteristics are also the total average (the total average of each radiation angle 360 ° in both orthogonal directions shown in FIG. 7 described later). The conventional structure was -0.59 dBi, but the structure shown in FIG. 3 was -0.72 dBi, almost unchanged (the larger the value, the better), and the radiation characteristic shown in FIG. 7 was obtained. . 7A, as shown in FIG. 8, the front side of the radiation electrode 2 of the antenna is the z axis, and the feeding point 2a is shown in FIG. 8 with respect to the center C of the radiation electrode 2. (B) shows the radiation characteristic in the yz plane which is the orthogonal direction. The average radiation characteristic of (a) is -0.85 dBi, -0.73 dBi of the conventional structure, and the average radiation characteristic of (b) is -0.59 dBi, which is slightly lower than -0.45 dBi of the conventional structure. However, there is almost no discoloration.

  That is, as a result of examining the influence of the antenna characteristics by providing the concave portion 1b on the dielectric substrate back surface 1 for surface mounting, the present inventors have found that the size of the concave portion 1b (the size and thickness of the dielectric substrate 1). FIG. 9 shows the change in VSWR at 1.575 GHz when the dimensions of the above-described example are variously changed (diameter when the depth of the concave portion is 1.5 mm and the concave portion 1b has a circular cross section). Furthermore, it has been found that the concave portion 1b is hardly affected by the concave portion 1b until the size of the concave portion 1b is about 10 mm in diameter. As a result, a space for soldering can be secured even when surface mounting is performed, the power feed pin 3 can be reliably connected to the mounting board, and the power feed pin 3 and the ground electrode 5 are short-circuited. I found that I can connect without letting it. The same tendency was obtained for the influence of the radiation characteristics on the size of the recess 1b.

  As described above, the concave portion 1b is provided on the back surface side of the through hole 1a through which the power supply pin 3 of the dielectric substrate 1 passes, and the other end portion 3b of the power supply pin is substantially flush with the exposed surface of the ground electrode 5. By doing so, the other end 3b side of the power supply pin 3 can be directly connected to the surface of the mounting substrate by soldering or the like. That is, the other end 3b of the power supply pin 3 has no flange, and even if the power supply pin 3 remains thin, there is a space due to the recess 1b around the power supply pin 3. The adhesive can be raised to fix the connection. As a result, it is possible to arrange a number of patch antennas on the surface of the mounting board all at once without penetrating the feed pin 3 through the through hole of the mounting board and performing soldering on the back side of the mounting board. It can be mounted simply by passing it through a reflow furnace, and the mounting efficiency can be greatly improved.

  Although the flange 1c is formed on the other end side of the power supply pin 3, it is necessary to slightly increase the size of the recess 1b. However, as described above, the recess 1b has a diameter of about 10 mm. Then, there is almost no influence on the characteristics, and by providing such a flange 1c, the reliability of adhesion to the mounting substrate can be further improved. Further, as shown in FIG. 3, first, only the power supply pin is connected and fixed to the mounting substrate by soldering or the like, and then the through hole of the assembly in which the dielectric substrate and the electrode portion are formed is inserted into the power supply pin. By connecting one end of the power supply pin and the radiation electrode using a reflow furnace or the like, it is possible to confirm in advance that there is no risk of a short circuit between the power supply pin and the mounting substrate and the power supply pin. Therefore, the reliability can be further improved.

  FIG. 4 is a cross-sectional explanatory view showing another embodiment of the surface-mounted patch antenna according to the present invention. That is, in this example, the other end portion 3b of the power feed pin 3 is formed of a movable pin whose projecting length can be changed via, for example, a spring, and the other end portion 3b is provided so as to project beyond the exposed surface of the ground electrode 5. It has been. A structure that can be surface-mounted on the surface of the mounting substrate by being pressed onto the mounting substrate by the moving force of the other end of the power supply pin 3 when being fixed on the mounting substrate and contracting while maintaining electrical contact with the surface of the mounting substrate. It has become. In other words, it is an example in which the connection is not a connection by an adhesive such as soldering but a connection by pressing. As a result, a space for storing an adhesive such as solder fillet is not required, and no recess is required on the back side of the dielectric substrate 1 as shown in FIG. Only the portion 3a is connected and fixed by the radiation electrode 2 and the solder material 6 and the other end portion 3b side is in a free state.

  Specifically, as shown in FIG. 4B, the power supply pin 3 is a movable pin 33 via a spring 32 inside a metal pipe 31 closed at one end 3 a side. With this structure, the movable pin 33 is pushed out by the spring property of the spring 32, and when pressed against the surface of the mounting substrate, the spring 32 contracts and mounts on the surface of the mounting substrate while ensuring electrical contact. be able to. The movable pin 33 is configured to be held by a caulking portion 31 a provided on the metal pipe 31 so as not to come out of the metal pipe 31. By adopting a structure in which the other end 3b side of the power supply pin 3 can be moved in this way, it can be connected to the power supply terminal of the mounting substrate by its movable force, and can be reliably brought into contact without a recess. . In addition, even if the spring is not a coil spring as shown in FIG. 4B, other members can be used as long as they have a spring property such as a leaf spring, and the movable pin does not come out. Other means can be used as the means.

  When such a movable pin is used as the power supply pin 3, a connection tool for pressing the patch antenna against the surface of the mounting substrate is required as in an example shown in FIG. 5 described later. Even if a connector as shown in Fig. 1 is not provided separately, the spring force is slight, so it can be fixed with double-sided adhesive tape to fix the conventional patch antenna on the mounting board, It is sufficient to fix by a conventional mounting method such as soldering or fixing to a mounting substrate.

  The example shown in FIG. 5 is a modification of the example shown in FIG. That is, in this example, the feed pin 3 is configured by a movable pin, and a flange 34 is formed below the feed pin 3, and a recess 1 b is formed on the back side of the through hole 1 a of the dielectric substrate 1. As described above, the recess 1b having a depth of about 1.5 mm and a diameter of 10 mmφ or less has almost no influence on the radiation characteristics. 1b is formed. As a result, the feed pin 3 is pushed so that the flange 34 touches the bottom of the recess, and its one end 3a is connected and fixed by the radiation electrode 2 and the solder material 6 so that the position of the feed pin 3 can be accurately aligned. It can be fixed and the working efficiency is greatly improved.

  As shown in FIG. 5A, the patch antenna mounting method is as shown in FIG. 5A. As in the example shown in FIG. 1, the dielectric substrate 1 having through holes 1a and recesses 1b formed at predetermined positions is used. The radiation electrode 2 is formed on the front surface and the ground electrode 5 is formed on the back surface, thereby forming the assembly 9. Next, as shown in FIG. 5 (b), the one end 3 a side of the power supply pin 3 having the movable pin 33 and the outer periphery 34 similar to that shown in FIG. 4 is connected to the back surface of the dielectric substrate 1. It inserts into the through-hole 1a from the side. In this case, the tip 3a is formed in the vicinity of the surface of the radiation electrode 2 when the flange 34 is inserted so as to contact the bottom of the recess 1b. After that, as shown in FIG. 5C, the one end 3a of the power feed pin 3 and the radiation electrode 2 are connected and fixed by a solder material 6 or the like. In this case, solder cream or the like is applied to the connection portion of the radiation electrode 2 so that the dielectric substrate 1 is turned upside down so that the feed pin 3 having the movable pin 33 and the flange 34 contacts the bottom of the recess 1b. In addition, by passing through a solder reflow furnace while being inserted into the through-hole 1a, a large number can be easily fixed together and the patch antenna 10 can be formed.

  On the other hand, as shown in FIG. 5 (d), a fixture 35 for fixing the patch antenna is attached to the mounting substrate 7 where the patch antenna is attached. The fixing device 35 is formed of, for example, a springy resin according to the size of the patch antenna, and the patch antenna 10 can be fixed to a predetermined place where the power supply pin 3 is connected to the power supply terminal of the mounting substrate 7. It is formed as follows. However, even without such a special fixture, the spring force can be reduced by using an adhesive such as double-sided tape, which is a conventional means for fixing a patch antenna, or a conductive adhesive that fixes the ground electrode with solder. It only has to be fixed with a force that can be withstood. Then, as shown in FIG. 5E, the patch antenna 10 is fixed by the fixture 35, so that the power supply pin can be connected to the power supply portion of the mounting substrate 7 and mounted. Note that even if the ground electrode 5 is not directly bonded to the ground portion of the mounting substrate 7 by the conductive member, it is only required to be connected at a high frequency, and it can be bonded with the usual double-sided adhesive tape as described above. .

  By using such a power supply pin having a movable pin, the power supply pin can be connected on the surface of the mounting substrate without providing a recess on the back side of the dielectric substrate, and the dielectric substrate has the same structure as before. However, the patch antenna can be surface-mounted on the mounting substrate. Further, since it can be mounted without soldering or the like, the patch antenna can be mounted on the mounting substrate by a very simple process. In addition, by forming a recess on the back surface of the dielectric substrate, it is possible to hook the power supply pin having a movable pin, and the process of connecting the power supply pin and the radiation electrode becomes very simple, with a certain quality. You can get things easily.

  According to the present invention, the other end of the power supply pin whose one end is connected and fixed to the radiation electrode can be directly connected to the surface of the mounting substrate by an adhesive such as soldering, or contact. The patch antenna can be mounted very easily and can be assembled at low cost. In addition, an assembly of a dielectric substrate having a through-hole and an electrode portion is formed without attaching the power supply pin, and the power supply pin is connected and fixed to the mounting substrate first, and the assembly is inserted into the power supply pin. Can also be implemented. By using such a mounting method, it is possible to check the connection between the power supply pin and the mounting board while simply mounting the patch antenna on the surface of the mounting board. Can be mounted.

It is explanatory drawing of the perspective view and cross section which show one Embodiment of the patch antenna by this invention. FIG. 8 is a cross-sectional explanatory view showing a modification of the patch antenna of FIG. 1. It is process explanatory drawing of one Embodiment which mounts the patch antenna by this invention. It is explanatory drawing which shows other embodiment of the patch antenna by this invention. It is explanatory drawing which shows the manufacturing process of the patch antenna shown by FIG. It is a figure which shows VSWR of the patch antenna mounted in the mounting board | substrate by the method of FIG. It is a figure which shows the radiation characteristic of the patch antenna mounted in the mounting board | substrate by the method of FIG. It is a figure which shows the positional relationship of the antenna in the case of the radiation | emission characteristic of FIG. It is a figure which shows the change of VSWR when the magnitude | size of the recessed part provided in a dielectric substrate is changed. It is explanatory drawing of the perspective and cross section which shows the conventional patch antenna. It is explanatory drawing which shows the example of the conventional surface mount type patch antenna.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dielectric board | substrate 1a Through-hole 1b Recessed part 2 Radiation electrode 3 Feeding pin 3a One end part 3b Other end part 3c Gutter part 5 Ground electrode

Claims (6)

  A dielectric substrate, a radiation electrode provided on a surface that is one surface of the dielectric substrate, a ground electrode provided on a back surface that is a surface facing the one surface of the dielectric substrate, and one end connected to the radiation electrode The other end of the patch antenna having a feed pin led out to the back side through a through hole provided in the dielectric substrate, wherein the through hole is formed on the back side of the dielectric substrate with the through hole. A recess having an inner circumference larger than the diameter of the through hole is formed, and the other end of the power supply pin is substantially flush with the exposed surface of the ground electrode provided on the back surface of the dielectric substrate. A surface mount type patch antenna that can be directly surface mounted on the surface of the mounting substrate.   The patch antenna according to claim 1, wherein a flange portion that facilitates connection to the mounting substrate is formed at the other end portion of the power supply pin.   A dielectric substrate; a radiation electrode provided on a surface that is one surface of the dielectric substrate; and a ground electrode provided on a back surface that is a surface opposite to the one surface of the dielectric substrate. A through hole is formed in the dielectric substrate at a portion corresponding to a position where the pin is connected and a position where the power supply pin is connected, and the through hole is substantially concentric with the through hole on the back surface side of the dielectric substrate. In addition, by forming a recess having an inner circumference larger than the diameter of the through-hole, a surface mount having a structure in which a power supply pin provided on the surface of the mounting substrate can be inserted into the through-hole and connected to the radiation electrode Type patch antenna.   A dielectric substrate, a radiation electrode provided on a surface that is one surface of the dielectric substrate, a ground electrode provided on a back surface that is a surface facing the one surface of the dielectric substrate, and one end connected to the radiation electrode A patch antenna having a feeding pin led to the back side through a through hole provided in the dielectric substrate, the other end of the feeding pin protruding through a spring. It is formed of a movable pin whose length can be changed, and the tip of the movable pin is provided so as to protrude from the exposed surface of the ground electrode. A surface-mountable patch antenna that can be surface-mounted on the surface of a mounting board by being pressed against the surface.   A recess larger than the through hole is formed on the back surface side of the dielectric substrate of the through hole, and a flange inserted into the recess is formed on the outer periphery of the power supply pin, and one end portion of the power supply pin with reference to the flange The surface mount type patch antenna according to claim 4, wherein the surface mount type patch antenna is fixed in connection with the radiation electrode. (A) A radiation electrode is formed on one surface of the dielectric substrate, a ground electrode is formed on the other surface, and a through-hole is formed in the radiation electrode, dielectric substrate and ground electrode in a portion where a feed pin connected to the radiation electrode is provided Forming an assembly of the dielectric substrate for the patch antenna formed with the electrode part,
(B) A power supply pin is erected and fixed to a power supply terminal on the surface of the mounting substrate on which the patch antenna is mounted,
(C) mounting the assembly for the patch antenna on the surface of the mounting substrate so that the feed pin penetrates the through hole of the assembly for the patch antenna;
(D) A method for mounting a surface-mounted patch antenna, wherein a front end portion of the feed pin is electrically connected to the radiation electrode.

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