JP4041444B2 - Antenna integrated high-frequency element storage package and antenna device - Google Patents

Description

  The present invention relates to an antenna-integrated high-frequency element storage package and an antenna device used in, for example, a wireless communication device such as a mobile phone and a wireless LAN, and other various communication devices.

  Conventionally, for example, a conventional antenna-integrated high-frequency element storage package (hereinafter also referred to as an antenna-integrated package) and an antenna device used in wireless communication devices such as mobile phones and wireless LANs, and other various communication devices, One using a strip antenna is known (for example, see Patent Document 1 below). An example is shown in FIG. In FIG. 6, reference numeral 111 denotes a dielectric substrate in which an antenna conductor 121 is arranged on the upper surface and a recess 141 for mounting the high-frequency element 151 is formed on the lower surface, 131 is a ground conductor formed in the dielectric substrate 111, 122. Is an internal wiring conductor that electrically connects the high-frequency element 151 and the antenna conductor 121.

  In this conventional antenna-integrated package, a microstrip antenna is configured by the antenna conductor 121, the ground conductor 131, and the portion of the dielectric substrate 111 above the ground conductor 131.

  However, since the conventional antenna-integrated package and antenna device use a microstrip antenna, the specific band is only about a few percent, and the frequency band is narrow in wireless communication applications that require a wide band. There was a point.

  In addition, since the microstrip antenna is used, the radiation characteristic is strong directivity in the zenith direction (upward in FIG. 6), the gain in the low elevation direction (lateral direction in FIG. 6) is low, and the antenna integrated package When installed horizontally, there was a problem that the sensitivity in the low elevation angle direction was low.

Therefore, an antenna integrated package and antenna device using a discone antenna, which is a broadband antenna, can be considered. An example is shown in FIG. In FIG. 9, reference numeral 111 denotes a dielectric substrate in which an antenna conductor 121 is formed on the upper surface, and a concave portion 141 for mounting the high-frequency element 151 is formed on the lower surface. Reference numeral 231 denotes a first substrate formed on the lower surface of the dielectric substrate 111. A ground conductor 122 is an internal wiring conductor that connects the high-frequency element 151 and the antenna conductor 121, 132 is connected to the first ground conductor 231, and is formed in the dielectric substrate 111 so as to surround the internal wiring conductor 122. It is a conical second grounding conductor having an upper end and a lower end opened.
Japanese Patent No. 3266491

  However, the antenna-integrated package using the discone antenna shown in FIG. 9 is provided with the first ground conductor 231 for grounding the second ground conductor 132, but the height of the antenna portion is affected by the influence. That is, the distance between the antenna conductor 121 and the first ground conductor 231 (H111 in FIG. 9) operates as an antenna in a frequency band equal to or higher than a frequency corresponding to about 1/8 to 1/4 wavelength, and the radiation characteristic is Although it has strong directivity in the low elevation angle direction (lateral direction in FIG. 9), there is a problem that an upper limit occurs in the frequency band.

  The present invention has been completed in view of the above problems, and an object of the present invention is to provide an antenna integrated package and an antenna device that operate in a wide band and have high sensitivity in a low elevation angle direction.

  The antenna-integrated high-frequency element storage package according to the present invention includes a dielectric substrate having an antenna conductor formed on the upper surface and a recess for accommodating and mounting the high-frequency element on the lower surface, and a lower surface of the dielectric substrate. A first ground conductor formed around the recess, an internal wiring conductor formed in the dielectric substrate by electrically connecting the antenna conductor and the high-frequency element, and the first ground conductor. A conical second grounding conductor having an upper end and a lower end that are formed in the dielectric substrate so that the lower end is electrically connected to the inner wiring conductor and surrounds the internal wiring conductor, and the second grounding conductor And an annular third ground conductor formed between the upper and lower ends of the second ground conductor and connected to the second ground conductor.

  In the antenna-integrated high-frequency element storage package according to the present invention, preferably, the distance between the third ground conductor and the antenna conductor is 1/10 to 1 of the lowest frequency within the operating frequency band of the high-frequency element. The length is / 8 wavelength and the diameter is 1/6 to 1/4 wavelength of the lowest frequency.

  In the antenna device of the present invention, the antenna-integrated high-frequency element storage package of the present invention is electrically connected to a wiring board having a fourth ground conductor on the top surface thereof, and the first ground conductor and the fourth ground conductor are electrically connected. It is characterized in that it is connected and mounted.

  The antenna-integrated high-frequency element storage package according to the present invention includes a dielectric substrate having an antenna conductor formed on the upper surface and a recess for receiving and mounting the high-frequency element on the lower surface, and a recess on the lower surface of the dielectric substrate. A first grounding conductor formed around the substrate, an internal wiring conductor formed in the dielectric substrate by electrically connecting the antenna conductor and the high-frequency element, and a lower end electrically connected to the first grounding conductor. A conical second grounding conductor having an open top and bottom end formed in the dielectric substrate so as to be connected and surrounding the internal wiring conductor, and a second grounding conductor surrounding the second grounding conductor And an annular third grounding conductor formed between the upper and lower ends and connected to the second grounding conductor, so that the first antenna-integrated package using the discone antenna Contact of two The conductor operates as an antenna in a frequency band equal to or higher than the frequency corresponding to about ８ to ¼ wavelength, and the radiation characteristic is strong directivity in a low elevation angle direction, and further surrounds the second ground conductor. Since the third ground conductor formed between the upper and lower ends of the second ground conductor and connected to the second ground conductor is formed, the distance between the antenna conductor and the third ground conductor is about 1/4. A new resonance occurs at a frequency corresponding to the wavelength. As a result, the upper limit of the frequency band generated by arranging the first ground conductor is increased, and the operating frequency band can be widened.

  In addition, since the antenna-integrated high-frequency element storage package of the present invention has a structure similar to a discone antenna, the height of the antenna portion, that is, the distance between the antenna conductor and the first ground conductor is Although it becomes longer than the height of the strip antenna, that is, the distance between the antenna conductor and the third ground conductor, a recess for accommodating the high-frequency element can be formed inside the second ground conductor. Therefore, as in a conventional antenna-integrated package, it is necessary to provide a height for forming a recess below the first ground conductor, that is, a distance between the first ground conductor and the lower surface of the dielectric substrate. Therefore, it is possible to prevent an increase in size and to reduce the height by integrating the antenna portion and the concave portion as the package.

  In the antenna-integrated high-frequency element storage package according to the present invention, preferably, the third ground conductor has a distance between the antenna conductor and 1/10 to 1/8 wavelength of the lowest frequency within the operating frequency band of the high-frequency element. Since the diameter is 1/6 to ¼ wavelength of the lowest frequency, resonance by the third ground conductor is near the upper limit of the frequency band caused by the installation of the first ground conductor. And the operating frequency band can be effectively widened.

  In addition, since the diameter of the third ground conductor is set to 1/6 to 1/4 wavelength of the lowest frequency in the operating frequency band of the high frequency signal, resonance by the third ground conductor can be effectively generated. The maximum frequency of the operating frequency band is increased, and the operating frequency band can be widened.

  In the antenna device of the present invention, the antenna-integrated high-frequency element storage package of the present invention is electrically connected to a wiring board having a fourth ground conductor on the upper surface, and the first ground conductor and the fourth ground conductor are electrically connected. Since it is connected and mounted, the length of the first ground conductor is supplemented by the fourth ground conductor, and the minimum frequency of the operating frequency band is the height of the antenna portion, that is, the antenna conductor and the first ground. Since it is determined by the distance to the conductor and the length of the fourth ground conductor, the length of the first ground conductor can be shortened, the lateral width of the dielectric substrate can be shortened, and the size can be reduced.

  The antenna-integrated high-frequency element housing package and the antenna device of the present invention will be described below.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of a first antenna-integrated package of the present invention. In FIG. 1, reference numeral 11 denotes a dielectric substrate in which the antenna conductor 21 is formed on the upper surface, and a recess 41 for accommodating and mounting the high-frequency element 51 on the lower surface, and 31 denotes a periphery of the recess 41 on the lower surface of the dielectric substrate 11. The first grounding conductor 22 is formed on the first grounding conductor 31, 22 is an internal wiring conductor formed in the dielectric substrate 11 by electrically connecting the high-frequency element 51 and the antenna conductor 21, and 32 is the lower end of the first grounding conductor 31. Are connected to each other and are formed in the dielectric substrate 11 so as to surround the internal wiring conductor 22, and a conical second grounding conductor having an upper end and a lower end opened, and 33 denotes the second grounding conductor 32. An annular third ground conductor formed between the upper and lower ends of the second ground conductor 32 and connected to the second ground conductor 32 so as to surround the second ground conductor 32.

  The first antenna-integrated package of the present invention is the height of the antenna portion, that is, between the antenna conductor 21 and the first ground conductor 31, as in the antenna-integrated package using the discone antenna shown in FIG. 1 (H11 in FIG. 1) operates as an antenna in a frequency band equal to or higher than a frequency corresponding to about ８ to ¼ wavelength, and the radiation characteristics are strong directivity in the low elevation direction, and the second grounding Since the third ground conductor 33 formed between the upper and lower ends of the second ground conductor 32 so as to surround the conductor 32 and connected to the second ground conductor 32 is formed, the antenna conductor 21 and the third conductor A new resonance occurs at a frequency corresponding to a quarter wavelength of the distance from the ground conductor 33. As a result, the upper limit of the frequency band generated by arranging the first ground conductor 31 is increased, and the frequency band can be widened.

  FIG. 7 is a diagram (graph) showing the reflection characteristics of the conventional antenna-integrated package shown in FIG. In FIG. 7, the horizontal axis represents frequency (GHz), the vertical axis represents VSWR (voltage standing wave ratio), and the characteristic curve represents the reflection characteristic, that is, the frequency characteristic of VSWR. The reflection characteristics shown in this diagram are obtained by electromagnetic field simulation (the diagram shown below was also obtained using the same electromagnetic field simulation). FIG. 7 shows that the frequency band with VSWR of 2 or less has a bandwidth of 2.3 GHz and the specific band is about 9%.

  FIG. 8 is a diagram showing the radiation characteristics of the conventional antenna-integrated package shown in FIG. In FIG. 8, the numbers on the outer circumference of the circle are the angle (°) indicating the azimuth with the zenith direction (upward direction in FIG. 1) being 0 °, the vertical axis is the normalized gain (dB), and the characteristic curve is radiation. The characteristic, that is, the azimuth characteristic of the normalized gain is shown. FIG. 8 shows that the gain in the zenith direction (0 °) is high and the gain in the low elevation direction, for example, ± 90 ° direction is about −20 dB.

  FIG. 10 is a diagram showing the reflection characteristics of the antenna-integrated package using the discone antenna shown in FIG. FIG. 10 shows the results obtained when the height H111 of the antenna portion is 2 mm, and the frequency band (bandwidth) from 20.8 GHz to 37.3 GHz, which is a frequency corresponding to the wavelength of the antenna portion height H111 being approximately 1/7 wavelength. It can be seen that the VSWR is 2 or less at a width of 16.5 GHz and an upper limit is generated in the frequency band.

  On the other hand, FIG. 2 is a diagram showing reflection characteristics of the first antenna-integrated package of the present invention shown in FIG. FIG. 1 shows a result obtained by setting the height H11 of the antenna portion to 2 mm, and the frequency band of 22.2 GHz or higher (bandwidth 27.8 GHz), which is a frequency corresponding to about 1/7 wavelength of the height H11 of the antenna portion. In the above, the VSWR is 2 or less, and it can be seen that the upper limit of the frequency band seen in FIG.

  FIG. 3 is a diagram showing the radiation characteristics of the antenna-integrated package of the present invention shown in FIG. From FIG. 3, it can be seen that the gain in the ± 90 ° direction is about −5 dB and has strong directivity in the low elevation direction.

  From the above, the frequency band of the first antenna-integrated package of the present invention has a bandwidth of 27.8 GHz or more, the bandwidth of the conventional antenna-integrated package shown in FIG. 6 is 2.3 GHz, and the discone shown in FIG. The frequency band can be wider than the bandwidth 16.5 GHz of the antenna integrated package using the antenna. Further, the gain in the low elevation angle direction of the first antenna-integrated package of the present invention is -5 dB in the ± 90 ° direction as shown in FIG. 3, and the ± 90 ° direction of the conventional antenna-integrated package shown in FIG. The gain can be made higher than -20 dB which is the gain of.

  Further, since the first antenna-integrated package of the present invention has a structure similar to a discone antenna, the height H11 of the antenna portion is the height of the microstrip antenna, that is, the antenna conductor 121 of FIG. Although the distance from the conductor 131 (H111A in FIG. 6) is higher, the recess 41 serving as a package can be formed inside the second ground conductor 32, so that the conventional antenna integrated package of FIG. Thus, it is not necessary to take the height for forming the concave portion 141 serving as a package below the ground conductor 131, that is, the distance from the ground conductor 131 to the lower surface of the dielectric substrate 111 (H111B in FIG. 6). By integrating the part and the package, an increase in size can be prevented.

  The reflection characteristics of the conventional antenna-integrated package shown in FIG. 7 were obtained when the height of the microstrip antenna (H111A in FIG. 6) was 0.8 mm.

  As described above, the height H11 of the antenna portion of the first antenna-integrated package of the present invention is 2 mm, which is higher than the height H111A of the antenna portion of the antenna-integrated package using the conventional microstrip antenna of 0.8 mm. However, an increase in size due to the integration of the antenna portion and the package can be prevented.

  In the first integrated antenna package of the present invention, the third ground conductor 33 is positioned below the antenna conductor 21 at a position corresponding to 1/10 to 1/8 wavelength of the lowest frequency in the operating frequency band (H33 in FIG. 1). Therefore, the resonance by the third ground conductor 33 occurs near the upper limit of the operating frequency band generated by the first ground conductor 31, and the operating frequency band can be effectively widened.

  In the first integrated antenna package of the present invention, the diameter of the third ground conductor 33 (outer diameter: L33 in FIG. 1) is set to 1/6 to 1/4 wavelength of the lowest frequency in the operating frequency band. Therefore, resonance by the third ground conductor 33 can be effectively generated, the maximum frequency of the operating frequency band can be increased, and the operating frequency band can be widened.

  The reflection characteristic of the first antenna-integrated package of the present invention shown in FIG. 2 is a result of setting H33 to 1.5 mm corresponding to about 1/9 wavelength of the lowest frequency 22.2 GHz in the operating frequency band. Resonance by the third ground conductor 33 occurs near the upper limit (37.3 GHz shown in FIG. 10) of the operating frequency band generated by the ground conductor 31, and the operating frequency band can be effectively widened.

  In addition, the reflection characteristic of the first antenna-integrated package of the present invention shown in FIG. 2 is that the length L33 of the third ground conductor 33 is 3 mm, which corresponds to about 1/5 wavelength of the lowest frequency 22.2 GHz in the operating frequency band. As a result, resonance by the third ground conductor 33 can be effectively generated, the maximum frequency of the operating frequency band can be increased, and the operating frequency band can be widened.

  FIG. 4 is a sectional view showing an example of an embodiment of the second antenna-integrated package of the present invention. In FIG. 4, 11 is a dielectric substrate having a structure in which a number of dielectric layers are laminated, in which an antenna conductor 21 is formed on the upper surface and a recess 41 for mounting the high-frequency element 51 is formed on the lower surface, and 31 is a dielectric substrate. 11 is a first ground conductor formed around the concave portion 41 on the lower surface of 11, and 22 is an internal wiring conductor that connects the high-frequency element 51 and the antenna conductor 21. 32A is a through conductor portion constituting the second ground conductor 32 formed between the layers of the dielectric substrate 11, and 32B is an inner conductor layer portion constituting the second ground conductor 32 formed in each layer. The through conductor portions 32A and the inner conductor layer portions 32B are alternately connected to constitute the second ground conductor 32. The second ground conductor 32 is formed in the dielectric substrate 11 so that its lower end is connected to the first ground conductor 31 and surrounds the internal wiring conductor 22, and has a conical shape with its upper and lower ends opened. It is said that. Reference numeral 33 denotes a third ground conductor formed between the upper and lower ends of the second ground conductor 32 so as to surround the second ground conductor 32 and connected to the second ground conductor 32.

  In the second package with integrated antenna according to the present invention, since the dielectric substrate 11 has a laminated structure, the third ground conductor 33 can be easily disposed between the upper and lower ends of the second ground conductor 32. In addition, the second ground conductor 32 and the third ground conductor 33 can be easily connected. Further, a plurality of third ground conductors 33 can be provided in the dielectric substrate 11, and in this case, the operating frequency band can be further widened. In addition, a passive element such as a filter or a balun can be formed in the middle of the internal wiring conductor 22 by using a laminated structure.

  In constructing the second antenna-integrated package of the present invention, the dielectric substrate 11, the antenna conductor 21, the internal wiring conductor 22, the first ground conductor 31, the second ground conductor 32, and the third ground conductor 33 are Those made of various materials used for the following high-frequency wiring boards can be used.

  For example, as the dielectric substrate 11, for example, ceramic materials such as alumina ceramics and mullite ceramics, inorganic materials such as glass ceramics, tetrafluoroethylene-ethylene resin (polytetrafluoroethylene; PTFE), tetrafluoroethylene- Fluorine resin and glass such as ethylene copolymer resin (tetrafluoroethylene-ethylene copolymer resin; ETFE), tetrafluoroethylene-perfluoroalkoxyethylene copolymer resin (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin; PFA) Resin-based materials such as epoxy resin and polyimide are used. Further, the shape and dimensions (thickness, width, length) of the dielectric substrate 11 are set according to the frequency used, the application, and the like.

The antenna conductor 21, the internal wiring conductor 22, the first ground conductor 31, the second ground conductor 32, and the third ground conductor 33 are a conductor layer made of a metal material for high-frequency signal transmission, such as a Cu layer, Mo -Ni plated layer and Au plated layer deposited on Mn metallized layer, Ni plated layer and Au plated layer deposited on W metallized layer, Cr-Cu alloy layer, Cr-Cu Ni plating layer and Au plating layer deposited on alloy layer, Ni—Cr alloy layer and Au plating layer deposited on Ta ₂ N layer, Pt layer and Au plating layer on Ti layer Formed by using a thick film printing method or various thin film forming methods, plating methods, and the like, which are formed using a Ni-Cr alloy layer or a Pt layer and an Au plating layer. Is done. The thickness, width, and the like are set according to the frequency and application of the transmitted high-frequency signal.

  The second antenna-integrated package of the present invention is manufactured as follows. First, when the dielectric substrate 11 is made of, for example, glass ceramics, a green sheet of glass ceramics is prepared, and a predetermined punching process is performed on the dielectric ceramic substrate 11 so as to form the internal wiring conductor 22 and the second grounding conductor 32. A through hole in which the portion 32B is disposed is formed. Thereafter, a conductor paste such as Cu is filled into the through-hole by screen printing, and the antenna conductor 21, the first ground conductor 31, the inner layer conductor portion 32 </ b> A of the second ground conductor 32, and the third ground conductor 33. The pattern of the conductor paste layer and, if necessary, the pattern of the conductor paste layer to be another predetermined internal wiring conductor are printed and applied. Next, baking is performed at 850 to 1000 ° C., and finally Ni plating and Au plating are applied to the surface of each conductor layer.

  FIG. 5 is a cross-sectional view showing an example of an embodiment of an antenna device using a third antenna-integrated package of the present invention. In FIG. 5, 10 is the first and second antenna-integrated packages of the present invention shown in FIGS. 1 and 4, and 61 is a wiring board having a fourth ground conductor 34 on the upper surface.

  The third antenna device of the present invention includes the first and second antenna-integrated packages 10 of the present invention shown in FIGS. 1 and 4 on the wiring board 61 having the fourth ground conductor 34 on the upper surface. Since the grounding conductor 31 and the fourth grounding conductor 34 are connected and mounted, the length of the first grounding conductor 31 (L11 in FIG. 5) is supplemented by the fourth grounding conductor 34, and the operating frequency is increased. The minimum frequency of the band can shorten the length L11 of the first ground conductor 31 by the height of the antenna portion (H11 in FIG. 5) and the length of the fourth ground conductor 34 (L61 in FIG. 5). The lateral width of the body substrate 11 can be shortened.

It is sectional drawing which shows an example of embodiment of the 1st antenna integrated high frequency element accommodation package of this invention. It is a graph which shows the reflective characteristic of the 1st antenna integrated type high frequency element accommodation package of this invention. It is a graph which shows the radiation characteristic of the 1st antenna integrated high frequency element accommodation package of this invention. It is sectional drawing which shows an example of embodiment of the 2nd antenna integrated high frequency element accommodation package of this invention. It is sectional drawing which shows an example of embodiment of the 3rd antenna integrated type high frequency element accommodation package and antenna apparatus of this invention. It is sectional drawing which shows the example of the conventional antenna integrated high frequency element accommodation package. It is a graph which shows the reflective characteristic of the conventional antenna integrated high frequency element storage package. It is a graph which shows the radiation characteristic of the conventional antenna integrated high frequency element storage package. It is sectional drawing which shows the example of the antenna integrated high frequency element accommodation package using the conventional discone antenna. 10 is a graph showing reflection characteristics of an antenna-integrated high-frequency element storage package using the discone antenna of FIG. 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Dielectric board | substrate 21 ... Antenna conductor 22 ... Internal wiring conductor 31 ... 1st grounding conductor 32 ... 2nd grounding conductor 33 ... 3rd grounding conductor 41 ... .Recess 51: high frequency element

Claims (3)

A dielectric substrate having an antenna conductor formed on the upper surface and a recess for accommodating and mounting a high-frequency element on the lower surface, and a first ground conductor formed around the recess on the lower surface of the dielectric substrate And an internal wiring conductor formed in the dielectric substrate by electrically connecting the antenna conductor and the high-frequency element, and a lower end thereof is electrically connected to the first ground conductor and the internal wiring A conical second ground conductor formed in the dielectric substrate so as to surround the conductor and having an upper end and a lower end opened, and upper and lower ends of the second ground conductor so as to surround the second ground conductor And an annular third grounding conductor formed between and connected to the second grounding conductor, the antenna-integrated high-frequency element storage package. The distance between the third ground conductor and the antenna conductor is 1/10 to 1/8 wavelength of the lowest frequency within the operating frequency band of the high frequency element, and the diameter is 1 of the lowest frequency. The antenna-integrated high-frequency element storage package according to claim 1, wherein the package has a length of / 6 to ¼ wavelength. The antenna-integrated high-frequency element storage package according to claim 1 or 2, wherein the first ground conductor and the fourth ground conductor are electrically connected to a wiring board having a fourth ground conductor on an upper surface. An antenna device characterized by being connected and mounted.

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