JP5873350B2 - Wireless module with integrated antenna - Google Patents

Description

  The present invention relates to an antenna integrated wireless module in which an antenna is provided on a circuit board.

  In recent years, there is an increasing demand for communication devices that can handle a frequency band from several hundred MHz to several tens of GHz. In such a communication device, an antenna having an electrical length of ¼ wavelength of the signal frequency of the use band (for example, 3 cm in the case of a wavelength of 2.4 GHz) is desirable. In order to reduce the size of the entire communication device, a proposal has been made to use a conductor pattern formed on a circuit board as an antenna (see, for example, Patent Document 1). By mounting such an antenna and a wireless module on a circuit board to form an antenna integrated wireless module, and mounting the antenna integrated wireless module on various communication devices, the entire communication device can be reduced in size.

JP 2002-204118 A

  By the way, when an antenna-integrated wireless module is mounted on a communication device, the antenna formed on the circuit board may not have designed antenna characteristics due to the influence of the device housing in which the module is incorporated. For this reason, the conventional antenna-integrated wireless module needs to tune the antenna conductor pattern for each mounted communication device or adjust the value of the passive element (capacitor, inductor, etc.) to correct the antenna characteristics. It was. However, in consideration of different effects for each product, tuning of the antenna pattern or adjustment of the passive elements has been performed, so that complicated work has been required.

  The present invention has been made in view of this point, and an object of the present invention is to provide an antenna-integrated radio module that can obtain a desired antenna characteristic for each product by eliminating complicated tuning work.

The antenna-integrated radio module of the present invention is provided on a circuit board, a high-frequency circuit that is provided on the circuit board and receives and / or transmits a signal of a predetermined frequency, and is provided on one surface or an inner layer surface of the circuit board, Provided separately from the circuit board on the antenna element connected to the high-frequency circuit and on the one surface or the other surface of the circuit board in the vicinity of the antenna that electromagnetically affects the antenna element. And an insulating sheet adhered to the same surface as one or the other surface of the circuit board on which the conductive element is provided, the conductive element being connected to the circuit by the insulating sheet. The conductive pattern is fixed to one or the other surface of the substrate, and the insulating sheet is a label on which arbitrary information is recorded .

  According to this configuration, since the influence on the antenna element from the device housing in which the antenna integrated radio module is incorporated by the conductor element can be reduced, it is necessary to tune the antenna characteristics for each communication device in which the antenna integrated radio module is mounted. Absent. Therefore, it is possible to realize an antenna-integrated radio module that can obtain desired antenna characteristics for each product.

The present invention also provides a circuit board, a high-frequency circuit that is provided on the circuit board and receives and / or transmits a signal having a predetermined frequency, and is provided on one surface or an inner layer surface of the circuit board and connected to the high-frequency circuit. An antenna element, and a conductor element provided separately from the circuit board in a region in the vicinity of the antenna that has an electromagnetic influence on the antenna element on one surface or the other surface of the circuit board. , And the conductor element is connected to a ground pattern of the circuit board .

The present invention also provides a circuit board, a high-frequency circuit that is provided on the circuit board and receives and / or transmits a signal having a predetermined frequency, and is provided on one surface or an inner layer surface of the circuit board and connected to the high-frequency circuit. An antenna element, and a conductor element provided separately from the circuit board in a region in the vicinity of the antenna that has an electromagnetic influence on the antenna element on one surface or the other surface of the circuit board. The high-frequency circuit is provided with a metal shield cover, and a part of the shield cover protrudes on one or the other surface of the circuit board on which the antenna element is provided. The conductor element is connected to a part of the protruding shield cover.

Moreover, this invention is equipped with the insulating sheet affixed on the same surface as the one or other surface of the said circuit board in which the said conductor element was provided, and the said conductor element is one or the other of the said circuit board by the said insulating sheet It may be a conductor pattern fixed to the surface.

The conductor element of the present invention may be a metal tape bonded to a sticking surface of the insulating sheet .

The conductor element of the present invention may be printed on the insulating sheet .

  According to the present invention, it is possible to realize an antenna-integrated radio module that eliminates complicated tuning work and obtains desired antenna characteristics for each product.

It is a schematic diagram of the antenna integrated radio module according to the first embodiment. It is a figure which shows the variation of a conductor pattern. It is a perspective view which shows the structural example of the antenna integrated radio module which concerns on 2nd Embodiment. FIG. 4 is a perspective view of the lower surface side of the antenna-integrated wireless module shown in FIG. 3. It is typical sectional drawing which follows the BB line shown to FIG. 4B. It is a schematic diagram of the antenna integrated radio | wireless module which concerns on 3rd Embodiment. It is a schematic diagram of the antenna integrated radio | wireless module which concerns on 4th Embodiment. It is a perspective view of the lower surface side of the antenna integrated radio module shown in FIG. FIG. 8 is a side view of the antenna-integrated radio module illustrated in FIG. 7. It is a schematic diagram of the antenna integrated radio | wireless module which concerns on 5th Embodiment. It is a schematic diagram of the antenna integrated radio module of the embodiment model. It is a schematic diagram of the antenna integrated radio module of a comparative example model. It is a figure which shows the relationship between radiation power and a frequency. It is a figure which shows the relationship between reflection loss and a resonant frequency.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of an antenna-integrated radio module 1 according to a first embodiment of the present invention. 1A is a top view of the radio module 1 with an integrated antenna, FIG. 1B is a bottom view of the radio module 1 with an integrated antenna, and FIG. 1C is a schematic arrow view along the line AA in FIG. 1B. It is sectional drawing.

  As shown in FIGS. 1A to 1C, the antenna-integrated wireless module 1 is mounted on a circuit board 11 having a substantially rectangular shape in a plan view and a central portion of an upper surface 11a (for example, one surface) of the circuit board 11. And a radio module 12 (high frequency circuit) that receives and / or transmits a signal of a predetermined frequency, and an antenna element 13 provided on the upper surface 11 a of the circuit board 11 along one short side of the circuit board 11. The antenna element 13 is composed of a meander-shaped conductor pattern, and is electrically connected to the passive element (capacitor, inductor, etc.) 19 and the wireless module 12. The antenna element 13 is not necessarily provided on the upper surface of the circuit board 11. The antenna element 13 may be provided on the lower surface of the circuit board 11 or may be provided on the inner layer surface of the circuit board 11.

  A connector 14 is mounted on the upper surface 11 a of the circuit board 11 in a region opposite to the region where the antenna element 13 is formed with the wireless module 12 interposed therebetween. Connected to the connector 14 are cables (not shown) from various communication devices on which the antenna-integrated wireless module 1 is mounted. In the circuit board 11, a through hole 15 a provided in the vicinity of one end of the antenna element 13 in the longitudinal direction and a through hole 15 b provided in parallel with the connector 14 are formed. Around the through holes 15a and 15b, lands 16a and 16b with exposed copper foil are provided. Screws (not shown) for fixing the antenna-integrated radio module 1 to various communication devices are inserted into the through holes 15a and 15b.

  The circuit components constituting the wireless module 12 are covered with a module storage cover 12a. A conductor pattern 17 (conductor element) and an insulating sheet 18 are arranged on the lower surface 11 b of the circuit board 11. The conductor pattern 17 is arranged along a long side of the circuit board 11 from both ends in the longitudinal direction of the linear part 17a and a straight part 17a disposed in a region facing the antenna element 13 along one short side of the circuit board 11. And a pair of extending portions 17b extending toward the central portion. The conductor pattern 17 is arranged such that the longitudinal direction of the straight line portion 17a substantially coincides with the longitudinal direction of the antenna element 13, and a part of one extending portion 17b overlaps the land 16a. A part of the conductor pattern 17 is connected to a ground pattern (not shown). The conductor pattern 17 acts to electromagnetically act on the antenna element 13 to correct antenna characteristics (for example, resonance frequency). For example, the resonance frequency of the antenna element 13 can be adjusted in an arbitrary direction by adjusting the arrangement position or shape of the conductor pattern 17. In other words, the conventional antenna-integrated wireless module achieves the same effect as trimming the antenna pattern end or adjusting the passive element 19 by adjusting the arrangement position or shape of the conductor pattern 17. Yes. The antenna characteristics can be corrected by adjusting the arrangement position or shape of the conductor pattern 17 in accordance with the shape of the housing of the product in which the antenna integrated wireless module is incorporated.

  The insulating sheet 18 is made of an insulating material, and is attached to the lower surface 11b of the circuit board 11 so as to cover at least a region where the conductor pattern 17 can be fixed. As the insulating sheet 18, for example, a label on which predetermined information related to the antenna integrated wireless module 1 is recorded can be used. By using a label as the insulating sheet 18, the conductor pattern 17 can be fixed without adding a member dedicated to fixing the conductor pattern 17, so that an increase in the cost of the antenna-integrated radio module 1 can be prevented.

  The conductor pattern 17 is not particularly limited in material and form as long as the influence on the antenna element 13 of the product-side casing can be reduced. For example, a metal tape can be used as the conductor pattern 17. In this case, the metal tape can be used by adhering to the sticking surface of the insulating sheet 18. By using a metal tape as the conductor pattern 17, the shape and dimensions of the conductor pattern 17 can be easily adjusted. The conductor pattern 17 may be printed on the insulating sheet 18. As a material constituting the conductor pattern 17, for example, a metal material such as copper or silver, a resin material having a high dielectric constant such as polyimide, or the like can be used. Among these, it is preferable to use copper as a material constituting the conductor pattern 17. The shape of the conductor pattern 17 is not particularly limited as long as the influence on the antenna characteristics of the antenna element 13 by the housing can be reduced, and can be changed as appropriate.

  2A and 2B are diagrams showing variations regarding the shape of the conductor pattern 17. As shown in FIG. 2A, the conductor pattern 17 may be a substantially L-shaped pattern in plan view. In the example shown in FIG. 2A, the conductor pattern 17 extends along the long side of the circuit board 11 from the straight part 17 a provided along one short side of the circuit board 11 and one end in the longitudinal direction of the straight part 17 a. Extending portion 17b. Further, as shown in FIG. 2B, the total length of the straight line portion 17 a may be shortened to a length from one end portion of the short side of the circuit board 11 to the central portion. In this way, by appropriately changing the shape of the conductor pattern 17, the antenna characteristics can be adjusted according to the influence received from the housing of various communication devices on which the antenna integrated wireless module 1 is mounted. Desired antenna characteristics can be obtained without trimming the conductor pattern of the element 13.

  Next, a second embodiment of the antenna-integrated radio module 1 will be described. In the following description, differences from the antenna-integrated radio module 1 shown in FIG. 1 will be mainly described to avoid duplication of description. In addition, the same reference numerals are given to components common to the antenna-integrated radio module 1 shown in FIG.

  FIG. 3 is a perspective view showing a configuration example of an antenna-integrated radio module 200 according to the second embodiment. 4 is a perspective view of the lower surface side of the antenna-integrated wireless module 200 shown in FIG. 3, FIG. 4A shows a state before the insulating sheet 18 is pasted, and FIG. 4B shows a state after the insulating sheet 18 is pasted. ing. FIG. 5 is a schematic cross-sectional view taken along the line BB in FIG. 4B.

  As shown in FIG. 3, in the antenna-integrated wireless module 200, an antenna element 202 is provided on the inner layer surface of the circuit board 201. The shape of the antenna element 202 is the same as that of the antenna element 13 of the first embodiment. As shown in FIG. 4, the antenna integrated wireless module 200 is provided with a ground pattern 203 in a region facing the wireless module 12 on the lower surface 201 b of the circuit board 201. The ground pattern 203 has a substantially rectangular shape in plan view and is covered with a resist (not shown). At the corners of the ground pattern 203, connection portions 203a from which the resist is removed are provided. The insulating sheet 18 also serves as a product label of the antenna integrated wireless module 1. The conductor pattern 17 is attached to the lower surface 201b of the circuit board 201 by the insulating sheet 18 in a state where one end overlaps the connecting portion 203a (see FIG. 5). By connecting one end of the conductor pattern 17 to the ground pattern 203 in this way, the conductor pattern 17 can be held at a stable potential. Therefore, when the antenna integrated wireless module 200 is mounted on various communication devices, the antenna element 202 is provided. It is possible to reduce the influence on the antenna element 13 from a housing (conductive block) arranged in the vicinity of the antenna element 13.

  FIG. 6 is a schematic diagram of an antenna-integrated radio module 300 according to the third embodiment. 6A is a top view of the antenna-integrated radio module 300, FIG. 6B is a bottom view of the antenna-integrated radio module 300, and FIG. 6C is a schematic cross-sectional view taken along line CC in FIG. 6B. is there.

  The conductor pattern 17 composed of a metal tape or the like has an advantage that various varieties can be easily prepared. On the other hand, the conductor pattern 17 (for example, a metal tape) corresponding to the variety needs to be connected to the ground or the signal system depending on the conditions required for the conductor pattern 17. In the antenna-integrated wireless module 300 shown in FIG. 6, the conductor pattern 17 is connected to the land 16a by using a screw attached to the land 16a, and the land 16a is connected to the ground or a signal system.

  A through hole 301 serving as a screw hole is formed in the center of the land 16a so as to penetrate the circuit board 11. With the end of the conductor pattern 17 overlapped with the land 16a, the end of the conductor pattern 17 is fixed to the land 16a by the screw head 302a of the metal screw 302 inserted into the through hole 301 from the lower surface side of the circuit board 11. ing. The metal screw 302 or land 16a is connected to a ground pattern (not shown) or a signal system. The conductor pattern 17 can be connected to a ground pattern or a signal system by screwing with a metal screw 302.

  FIG. 7 is a schematic diagram of an antenna-integrated radio module 400 according to the fourth embodiment. FIG. 7A is a top view of the radio module 400 with an integrated antenna, and FIG. 7B is a bottom view of the radio module 400 with an integrated antenna. FIG. 8 is a perspective view of the lower surface side of the antenna-integrated radio module 200 shown in FIG. FIG. 9 is a side view of the antenna-integrated wireless module 400 shown in FIG. FIG. 8 shows a state before the insulating sheet 18 is stuck, and FIG. 9 shows a state after the insulating sheet 18 is stuck.

  In the antenna-integrated wireless module 400 shown in FIG. 7, the conductor pattern 17 is connected to the ground using the leg portion 401 a of the module housing cover 401. The module housing cover 401 of the antenna-integrated wireless module 400 is provided with leg portions 401 a for attaching the cover itself to the upper surface of the circuit board 11. On the other hand, a through hole 402 is formed in the circuit board 11 corresponding to the position of the leg 401 a of the module storage cover 401. On the lower surface 11b of the circuit board 11, the linear part 17a of the conductor pattern 17 is provided along the short side of the circuit board 11, and the extending part 17b covers the through hole 402 from one end of the linear part 17a. 11 extends to the vicinity of the center of the long side. The extension 17 b is provided with a through hole 403 that penetrates the conductor pattern 17 in a region corresponding to the through hole 402 of the circuit board 11.

  As shown in FIGS. 8 and 9, the corresponding leg portion 401 a of the module housing cover 401 is inserted into the through hole 403, and the portion protruding from the lower surface 11 b of the circuit board 11 is bent to form the conductor pattern 17 and the insulation. The sheet 18 is fixed. When the module storage cover 401 is made of a metal material, the conductor pattern 17 can be electrically connected to the metal module storage cover 401a by bringing the leg 401a and the conductor pattern 17 into contact with each other. The cover 401 a can be used as the ground for the conductor pattern 17.

  As described above, according to the present embodiment, even when the antenna-integrated wireless module 1 is mounted on various communication devices, it is possible to reduce the influence from a housing or the like disposed around the antenna element 13. Since the conductor pattern 17 can be easily adjusted, the troublesome work of adjusting the passive element 19 by trimming the conductor pattern of the antenna element for each communication device in which the antenna integrated wireless module 1 is mounted can be eliminated. Therefore, it is possible to realize the antenna-integrated radio module 1 that can greatly improve work efficiency and obtain desired antenna characteristics.

  In the above description, the conductor pattern 17 is provided in the vicinity of the antenna element 13 to correct the antenna characteristics. However, the antenna pattern itself is adjusted by fixing the conductor pattern with an insulating sheet so that the antenna element 13 extends. May be.

  A fifth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a schematic diagram of an antenna-integrated radio module 500 according to the fifth embodiment. FIG. 10A shows a state before antenna adjustment, and FIG. 10B shows a state after antenna adjustment. The description will focus on differences from the antenna-integrated radio module 1 according to the above-described embodiment. In FIG. 10, the same components as those in the antenna-integrated radio module 1 shown in FIG.

  In the antenna-integrated radio module 500 according to the present embodiment, the antenna element 13 made of a meander-shaped metal pattern is provided on the upper surface 11 a of the circuit board 11. As shown in FIG. 10A, a part of a conductor pattern 501 having an arbitrary shape is connected to one end of the antenna element 13, and an insulating sheet 502 is attached to a predetermined region including the conductor pattern 501 from above. 10B, the conductor pattern 501 is fixed to the upper surface 11a of the circuit board 11, and the antenna element 13 is extended by the conductor pattern 501. The conductive pattern 501 may be attached with an insulating sheet 502 or may be printed. By connecting the conductor pattern 501 to the antenna element 13 and extending the antenna element 13 in this way, the antenna characteristics can be arbitrarily adjusted without trimming the antenna element 13 itself.

  As described above, according to the present embodiment, the entire length of the antenna element 13 can be arbitrarily adjusted by the conductor pattern 501 without trimming the antenna element 13, and therefore the work of tuning the characteristics of the antenna element for each product Can be simplified.

  Next, the simulation results of the antenna characteristics of the example model of the antenna integrated radio module according to the above-described embodiment will be described in comparison with the comparative example model. In the simulation model described below, the antenna characteristics at each distance were simulated by changing the distance between the antenna integrated wireless module and the conductor block (corresponding to the casing). FIG. 11 shows an antenna-integrated radio module 600 as an example model, and FIG. 12 shows an antenna-integrated radio module 700 as a comparative model. The antenna-integrated wireless module 600 of the example model is provided with the L-shaped conductor pattern 601 on the back surface of the substrate, whereas the antenna-integrated wireless module 700 of the comparative example model is the L-shaped conductor pattern 601 from the back surface of the substrate. Is removed.

  FIG. 13 is a diagram illustrating a relationship between radiated power and frequency, which is one of simulations. FIG. 13A shows a simulation result when the distance between the antenna integrated wireless module and the conductor block is set to 10 mm, FIG. 13B shows a simulation result when the distance between both is set to 1 mm, and FIG. The simulation result when the interval is set to 0 mm is shown. In the figure, the characteristic curve indicated by a dotted line is a comparative example model, and the characteristic curve indicated by a solid line is an example model.

  As shown in FIG. 13A, the example model (600) and the comparative example model (700) have a radiated power of −3.0 dB to −5.0 dB when the distance is 10 mm within the frequency range of 2400 MHz to 2500 MHz. Become. Moreover, as shown in FIG. 13B, the radiated power decreases as the distance approaches, and the radiated power becomes −8.0 dB to −10.0 dB when the distance is 1 mm. On the other hand, as shown in FIG. 13C, when the distance is 0 mm, the radiated power of the example model (600) is −8.0 dB to −9.0 dB, whereas the comparative model (700) is compared. The radiated power is -10.0 dB to -11.0 dB. From this result, it can be seen that the example model (600) can reduce the influence of the conductor block on the radiated power of the antenna compared to the comparative example model (700).

  FIG. 14 is a diagram illustrating the relationship between the reflection loss and the resonance frequency, which is one of simulations in the example model and the comparative example model. 14A shows a simulation result of the antenna integrated radio module 700 of the comparative example model, and FIG. 14B shows a simulation result when the antenna integrated radio module 600 of the example model and the conductor block are close to each other (0 mm). FIG. 14C shows a simulation result in a state (0 mm) in which the antenna integrated radio module 700 of the comparative example model and the conductor block are close to each other.

  As shown in FIG. 14A, the antenna-integrated radio module 700 of the comparative example model has a resonance frequency of the module alone of about 2.4 GHz. The same characteristics as those of the comparative example model were confirmed for the antenna integrated radio module 600 of the example model. Further, as shown in FIG. 14B, the resonance frequency of the antenna-integrated radio module 600 of the example model hardly changes even when it is close to the conductor block. On the other hand, as shown in FIG. 14C, it can be confirmed that the antenna-integrated wireless module 700 of the comparative example model has a resonance frequency reduced to about 2.3 GHz when close to the conductor block. From this result, it can be seen that the antenna integrated radio module 600 of the example model can reduce the influence of the conductor block on the resonance frequency of the antenna.

  The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the example in which the meandering conductor pattern formed on the circuit board is used as the antenna element 13 has been described. However, the antenna element 13 may be a chip antenna mounted on the circuit board 11 or the like. Other antenna elements may be used.

  The present invention is effective as an antenna-integrated radio module in which antenna elements are integrally formed on a circuit board as a pattern.

1, 200, 300, 400, 500, 600, 700 ... Antenna-integrated radio module 11, 201 ... Circuit board 11a, 201a ... Upper surface 11b, 201b ... Lower surface 12 ... Wireless module 12a, 401 ... Module housing cover 13, 202 , 602 ... Antenna element 14 ... Connector 15a, 15b, 301, 402, 403 ... Through hole 16a, 16b ... Land 17, 501, 601 ... Conductor pattern 17a ... Linear part 17b ... Extension part 18,502 ... Insulating sheet 203a ... Connection part 302 ... Screw 302a ... Screw head 401a ... Leg part

Claims (6)

A circuit board;
A high frequency circuit provided on the circuit board for receiving and / or transmitting a signal of a predetermined frequency;
An antenna element provided on one or inner surface of the circuit board and connected to the high-frequency circuit;
A on one surface or the other surface of the circuit board, near the antenna area to which the electromagnetic effect on the antenna element, anda conductive element which is disposed separately from said circuit board,
Comprising an insulating sheet adhered to the same surface as one or the other surface of the circuit board provided with the conductor element;
The conductor element is a conductor pattern fixed to one or the other surface of the circuit board by the insulating sheet,
The wireless module with an integrated antenna , wherein the insulating sheet is a label on which arbitrary information is recorded . A circuit board;
A high frequency circuit provided on the circuit board for receiving and / or transmitting a signal of a predetermined frequency;
An antenna element provided on one or inner surface of the circuit board and connected to the high-frequency circuit;
On one surface of the circuit board or the other surface, in the vicinity of the antenna that electromagnetically affects the antenna element, a conductor element provided separately from the circuit board, and
Features and to luer antenna integrated radio module that the conductor element is connected to the ground pattern of the circuit board. A circuit board;
A high frequency circuit provided on the circuit board for receiving and / or transmitting a signal of a predetermined frequency;
An antenna element provided on one or inner surface of the circuit board and connected to the high-frequency circuit;
On one surface of the circuit board or the other surface, in the vicinity of the antenna that electromagnetically affects the antenna element, a conductor element provided separately from the circuit board, and
The high-frequency circuit is provided with a metal shield cover, and a part of the shield cover protrudes on one or the other surface of the circuit board on which the antenna element is provided, and the protruding shield features and to luer antenna integrated radio module that the conductor element is connected to a part of the cover. Comprising an insulating sheet adhered to the same surface as one or the other surface of the circuit board provided with the conductor element;
4. The antenna-integrated radio module according to claim 2 , wherein the conductor element is a conductor pattern fixed to one or the other surface of the circuit board by the insulating sheet. The antenna-integrated radio module according to any one of claims 1 to 4, wherein the conductor element is a metal tape bonded to a sticking surface of the insulating sheet. The antenna-integrated radio module according to any one of claims 1 to 5, wherein the conductor element is printed on the insulating sheet.

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