TWI398986B - Multi - frequency antenna - Google Patents

Description

Multi-frequency antenna

The present invention relates to a multi-frequency antenna, and more particularly to a hybrid planar inverted-F broadband antenna that utilizes multiple frequencies.

An antenna that transmits signals using electromagnetic principles has become an important electronic component in the developed era of communication. In order to cope with the generation of various types of miniaturized mobile communication devices, such as mobile phones, global positioning devices, smartphones, etc., because these devices are designed to be portable, the size is not large, so the miniaturization of the antenna is an inevitable development trend. .

Currently, in order to improve transmission efficiency, mobile phones are moving forward from generation to generation, such as first-generation (1G) AMPS, NMT and TACS, second-generation (2G) GSM, CDMA and TDMA, and the second generation has transmitted data. The speed is increased by 9.6kpbs to 14.4kbps, which can fully satisfy the voice transmission. 2.5 generation (2.5G) GPRS, 2.75G EDGE, third generation (3G) WCDMA, CDMA-2000 and TD-SCDMA, the third generation data transmission speed has reached 2Mbps in a stable environment, and can be extended to audio and video The transmission of multimedia materials. Subsequent developments include 3.5G WiMax, and even low-power PHS phones...etc. This development has made the demand for multi-mode and multi-frequency antennas more and more demanding. Among them, in order to receive multi-mode, multi-frequency signals, but also to meet the small size of the design, but also to make the antenna gain effect is good, the antenna design is more and more challenging.

The planar inverted-F antenna (PIFA) is an ideal antenna. The resonance of the energy between the antenna radiator and the metal plate is used to amplify the bandwidth, which is a development direction for solving multi-frequency.

Please refer to the Patent No. 549620 of the Republic of China, which further combines a loop antenna with a planar inverted-F antenna to increase the bandwidth. The antenna uses the antenna radiator to generate a ring structure, and thus occupies a large amount of planar radiation area. Although it can cause the effect of the loop antenna and increase the bandwidth, the effective area of the antenna plane is excessively large and the design space is wasted.

Accordingly, it is a primary object of the present invention to provide a multi-frequency antenna that can further improve the above problems.

The object of the present invention is to provide a multi-frequency antenna, which has a specific small and multi-band frequency, and has an ideal radiation field shape and gain effect. Further, the multi-frequency band covers the frequency range required for GSM, Edge, and WCDMA.

The present invention relates to a multi-frequency antenna comprising a dielectric substrate, a metal plate, a metal base tape, a first metal strip, a second metal strip, and a resonant metal strip.

The dielectric substrate has upper and lower surfaces, wherein the opposite directions of the upper surface are divided into a forward direction, a backward direction, a left direction, and a right direction.

The metal plate is disposed on a lower surface of the dielectric substrate. A grounding wire is disposed on the rear edge of the dielectric substrate and extends upward, and the upper end thereof is a grounding point.

The metal base strip extends from the ground point toward the front surface of the dielectric substrate, wherein the left and right sides of the metal base strip are respectively a first area and a second area, and the ground point is The metal plate is contacted with the grounding wire.

The first metal strip is disposed above the upper surface of the dielectric substrate The metal base tape extends toward the second region adjacent one end of the grounding point.

The second metal strip is disposed above the upper surface of the dielectric substrate, and extends from the end of the metal base strip to the second region, and the end of the second metal strip is backward and backward. Fold back to be adjacent to the first metal strip.

The resonant metal strip is disposed above the upper surface of the dielectric substrate and extends from the metal base strip to the first region at an end different from the ground point.

Among them, the multi-frequency antenna is in the range of 824 MHz to 2170 MHz, and generates a plurality of operating frequency bands.

Therefore, the multi-frequency antenna of the present invention is a multi-frequency hybrid planar inverted-F broadband antenna, which utilizes the mutual design of the multi-metal strips to enable it to have a specific small and multi-band, and has an ideal radiation field shape. Further with this gain effect, this multi-frequency range covers the range of frequencies required for GSM, Edge, and WCDMA.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

Please refer to FIG. 1 and FIG. 2 , which is a schematic diagram of the appearance of the viewing angle of the multi-frequency antenna 30 of the present invention. FIG. 2 is a schematic diagram showing the appearance of the viewing angle of the multi-frequency antenna 30 of the present invention. The invention relates to a multi-frequency antenna 30, which is suitable for various handheld mobile communication devices such as a personal digital assistant (PDA), a smart phone, other multi-mode multi-frequency mobile phones, or the like. Remote communication electronics. The multi-frequency antenna 30 of the present invention is a hybrid planar inverted-F broadband antenna, which is obtained in a predetermined frequency band. The ideal field effect and gain effect is an improved design for the metal microstrip distribution of the antenna radiator 36.

The multi-frequency antenna 30 includes a dielectric substrate 32, a metal plate 34 disposed on the lower surface of the dielectric substrate 32, and an antenna radiator 36 disposed above the upper surface Up of the dielectric substrate 32. The antenna radiator 36 includes a metal base tape 40, a first metal strip 42, a second metal strip 44, and a resonant metal strip 46.

The dielectric substrate 32 may be a glass fiber substrate (FR4) substrate having upper and lower surfaces Up and Down, wherein the upper surface Up is opposed to the front direction F, the backward direction B, the left direction L, and the right direction R. Referring to FIG. 2, it can be seen that the metal plate 34 is disposed on the lower surface of the dielectric substrate 32.

Referring to Figure 3, Figure 3 is a side cross-sectional view of the multi-frequency antenna 30 of the present invention. It can be seen from the side view that the upper surface Up of the dielectric substrate 32 is the antenna radiator 36, the lower surface of the dielectric substrate 32 is the metal plate 34, and the grounding wire 50 is turned to the edge B of the dielectric substrate 32, and the antenna radiator 36 is turned on and off. Metal plate 34.

Wherein, the metal base tape 40 is connected to the metal plate 34 by the grounding wire 50 from the grounding point (the upper end of the grounding wire 50), and the metal base tape 40, the grounding conductor 50, and the metal plate 34 form a side profile of the ㄈ type. This shape will be similar to the resonance effect of the loop antenna, and the effective bandwidth will be increased. In addition to benefiting the performance improvement of the antenna of the present invention, the design of the loop antenna on the plane is well known, and the design effect of the loop resonance is placed in the vertical direction. Space, making full use of the design space around the antenna, is very helpful for the miniaturization of the antenna.

For the effect of the loop resonance described above, the distance between the feed point and the ground point can be adjusted, and the dielectric constant of the dielectric substrate 32 can be adjusted to change the capacitance effect, which is equivalent to a loop antenna, and can be adjusted to achieve an ideal bandwidth. And frequency.

Referring to FIG. 4 in conjunction with FIG. 1, FIG. 4 is a plan view of the multi-frequency antenna 30 of the present invention. As can be seen, the metal base tape 40 is disposed above the upper surface Up of the dielectric substrate 32, and extends from the grounding point (the upper end of the grounding conductor 50) toward the front F, wherein the left and right sides of the metal base tape 40 are respectively L and R sides. For a first region 60 and a second region 62, the grounding point contacts the metal plate 34 with the grounding wire 50 downward. Further, the feed point 52 of the multi-frequency antenna 30 is at the end of the metal base tape 40 different from the ground point and extends downward to the upper surface Up of the dielectric substrate 32.

The first metal strip 42 is disposed above the upper surface Up of the dielectric substrate 32 and extends laterally from the metal base strip 40 adjacent to one end of the ground point toward the second region 62.

The second metal strip 44 is also disposed above the upper surface Up of the dielectric substrate 32, and extends from the metal base strip 40 at the end of the ground point (the end of the feed point 52) to the second region 62, the second metal After the belt 44 extends toward the right R beyond the right end boundary of the first metal strip 42, it is turned toward the rear B, and then beyond the boundary of the rear edge of the first metal strip 42, the end of the second metal strip 44 is further The leftward L folds back adjacent to the first metal strip 42, wherein the second metal strip 44 is longer than the first metal strip 42.

In addition, the grounding point is disposed above the B edge of the dielectric substrate 32, and the first metal strip 42 is adjacent to and along the back side of the dielectric substrate 32 to the B side. The edge of the second metal strip 44 is folded back and disposed on the rear side of the dielectric substrate 32 to the B side, but below the first metal strip 42 and adjacent to and along the dielectric substrate 32 to the B edge. Adjacent to the first metal strip 42, wherein the first metal strip 42 is disposed in parallel with the second metal strip 44 before and after folding back. The first metal strip 42 is resonated by the second metal strip 44 to form a portion of the high frequency portion. The second metal strip 44 is also resonated by the first metal strip 42 to form a portion of the low frequency.

The resonant metal strip 46 is disposed above the upper surface Up of the dielectric substrate 32 and extends laterally from the metal base strip 40 to the end of the ground point (ie, the end of the feed point 52) toward the first region 60.

As described above, the multi-frequency antenna 30 further illustrates that the second metal strip 44 is expanded into a first block metal 70 in the second region 62 at the turn of the fold. The first block metal 70 further includes a first sub-block metal 7002 and a second sub-block metal 7004. The first block metal 7002 extends from the turn of the second metal strip 44 back to the inside. Forming, the second block metal 7004 is formed to expand outward from the turn where the second metal strip 44 is folded back to form.

In addition, the resonant metal strip 46 expands in the first region 60 toward the rearward B to a second block metal 72, by which the expanded block metal has a more desirable resonance effect on the entire multi-frequency antenna 30.

The first region 60 and the second region 62 correspond to the same strip plane, and the metal base tape 40, the first metal strip 42, the second metal strip 44, and the resonant metal strip 46 of the multi-frequency antenna 30 are disposed at 55 mm. *20mm area.

Further, according to an embodiment specification, the metal base tape 40 has a length ranging from 10 mm to 15 mm, the first metal strip 42 is approximately 17 mm to 22 mm long, and the second metal strip 44 is not folded back, that is, the forward F long type. The length of the region (including the region of the second block metal 7004 extension) is about 44 mm to 50 mm, and the length of the second metal strip 44 folded back to be very close to the first metal strip 42 is also about 15 mm. The resonant metal strip 46 is approximately 3 mm to 6 mm long, and the depth of the second block metal 72 extending toward the rear B is more than 1 cm.

With such specifications, the multi-frequency antenna 30 is in the range of 824 MHz to 2170 MHz, resulting in a plurality of operating frequency bands. In particular, it is required for GSM and Edge in the two bands of 824MHz to 960MHz and 1710MHz to 1990MHz respectively. The 824MHz to 894MHz, 1850MHz to 1990MHz, and 1920MHz to 2170MHz three bands are required for WCDMA.

In these ranges, at least five dual-mode antennas with working frequency bands are generated, which can resonate with the commonly used quad-band of GSM (824~894MHz, 880~960MHz, 1710~1880MHz, 1850~1990MHz), and the WCDMA BandI department. (1920~2170MHz), because the commonly used frequency band of WCDMA is BandI/BandII/BandV (1920~2170MHz, 1850~1990MHz, 824~894MHz), the multi-frequency antenna 30 can be used in the GSM quad-band system on the market, and WCDMA III. The frequency system and any communication system that can be covered by this band.

Further explanation, it can also cover 830~840MHz upload and 875~885MHz download (daily), 880~915MHz upload and 925~960MHz download (European EGSM 900), 1710~1785MHz upload and 1805~1880MHz download (daily DCS) 1800), 1710~1755MHz upload and 2110~2155MHz download (US), 1749.9~1784.9MHz upload and 1844.9~1879.9MHz download (Japanese), 824~849MHz upload and 869~894MHz download (US GSM 850), 1850~1910MHz upload And 1830~1990MHz download (US PCS 1900), 1920~1980MHz upload and 2110~2170MHz (European, Asian regulations) and other eight working frequency bands.

The benefits of the band with the ideal efficiency are shown in the following table, where more than 40% of the work efficiency is acceptable work efficiency, and more than 60% is very ideal work efficiency.

As can be seen from the table, most of them are in the 60% ideal working efficiency range.

Further, please refer to FIG. 5, which is a side cross-sectional view of still another embodiment of the multi-frequency antenna 30 of the present invention. The upper surface Up of the dielectric substrate 32 may be further attached with a resonant metal plate 80. The resonant metal plate 80 is placed between the antenna radiator 36 and the metal plate 34, and the resonant metal plate 80 is rearwardly directed to the B edge and the grounding conductor 50. The contact connection, wherein the resonant metal plate 80 excavates a plate hole 8002 at the point where the feed point 52 contacts the dielectric substrate 32 to avoid contact with the feed point 52.

Referring to FIG. 6, FIG. 6 is a schematic top view of the resonant metal plate 80 in the multi-frequency antenna 30 of the present invention. It can be seen from FIG. 6 that the resonant metal plate 80 is a large area. The metal region, and the shape and position of the plate hole 8002 can be clearly seen. The shape of the plate hole 8002 in the figure is circular, but the present invention is not limited to a circle, and a rectangle, a polygon, etc. are included in the scope of the present invention. The resonance metal plate 80 can resonate to make the bandwidth and the overflow effect of the multi-frequency antenna 30 of the present invention more desirable.

Therefore, the multi-frequency antenna 30 of the present invention is a multi-frequency hybrid planar inverted-F broadband antenna, which utilizes the mutual design of the multi-metal strips to enable a specific small and multi-band, and has an ideal radiation field. Shape and gain effects, further, this multi-frequency range covers the range of frequencies required for GSM, Edge, and WCDMA.

The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed.

30‧‧‧Multi-frequency antenna

32‧‧‧Dielectric substrate

34‧‧‧Metal plates

36‧‧‧Antenna radiator

40‧‧‧Metal baseband

42‧‧‧First metal strip

44‧‧‧Second metal belt

46‧‧‧Resonant metal strip

Up‧‧‧Upper surface

Down‧‧‧ lower surface

F‧‧‧ Forward

B‧‧‧Backward

L‧‧‧Left

R‧‧‧Right

50‧‧‧Grounding wire

52‧‧‧Feeding point

60‧‧‧First area

62‧‧‧Second area

70‧‧‧First block metal

7002‧‧‧First block metal

7004‧‧‧Second block metal

72‧‧‧Second block metal

80‧‧‧Resonance metal plate

8002‧‧‧ board hole

1 is a schematic view showing the appearance of a multi-frequency antenna of the present invention; FIG. 2 is a schematic view showing the appearance of a multi-frequency antenna of the present invention; FIG. 3 is a side cross-sectional view of the multi-frequency antenna of the present invention; FIG. 5 is a side cross-sectional view showing still another embodiment of the multi-frequency antenna of the present invention; and FIG. 6 is a top plan view showing a resonant metal plate in the multi-frequency antenna of the present invention.

30‧‧‧Multi-frequency antenna

32‧‧‧Dielectric substrate

36‧‧‧Antenna radiator

Up‧‧‧Upper surface

40‧‧‧Metal baseband

42‧‧‧First metal strip

44‧‧‧Second metal belt

46‧‧‧Resonant metal strip

F‧‧‧ Forward

B‧‧‧Backward

L‧‧‧Left

R‧‧‧Right

50‧‧‧Grounding wire

52‧‧‧Feeding point

60‧‧‧First area

62‧‧‧Second area

70‧‧‧First block metal

7002‧‧‧First block metal

7004‧‧‧Second block metal

72‧‧‧Second block metal

Claims (12)

A multi-frequency antenna comprising: a dielectric substrate having upper and lower surfaces, wherein the opposite directions of the upper surface are divided into a forward direction, a backward direction, a left direction, and a right direction; a metal plate Provided on the lower surface of the dielectric substrate; a metal base tape extending forwardly from a grounding point to the upper surface of the dielectric substrate, wherein the left and right sides of the metal base tape are respectively a first And a second region, the metal base tape is contacted from the grounding point by a grounding wire to contact the metal plate; a first metal strip is disposed above the upper surface of the dielectric substrate, adjacent to the metal base tape One end of the grounding point extends toward the second region; a second metal strip is disposed above the upper surface of the dielectric substrate, and the second metal strip extends from the end of the grounding point to the second region, the second The end of the metal strip is folded back toward the left to be adjacent to the first metal strip; a resonant metal strip is disposed above the upper surface of the dielectric substrate from the metal base strip The end of the grounding point extends toward the first region; and a resonant metal plate is attached to the upper surface of the dielectric substrate, and the rearward edge of the resonant metal plate is in contact with the grounding wire; wherein the multi-frequency antenna system In the range of 824 MHz to 2170 MHz, a number of operating frequency bands are generated. The multi-frequency antenna of claim 1, wherein the feeding point of the multi-frequency antenna is different from the end of the grounding point. The multi-frequency antenna according to claim 1, wherein the metal baseband The grounding conductor and the metal plate form a side view of the ㄈ type. The multi-frequency antenna of claim 1, wherein the second metal strip is longer than the first metal strip. The multi-frequency antenna of claim 4, wherein the grounding point is disposed above a rearward edge of the dielectric substrate, the first metal strip is disposed adjacent to and along a rearward edge of the dielectric substrate, the first The end of the second metal strip is folded back and disposed on the rear side of the dielectric substrate, and adjacent to and extending along the rear edge of the dielectric substrate to be adjacent to the first metal strip. The multi-frequency antenna of claim 5, wherein the first metal strip is parallel to the folded second metal strip. The multi-frequency antenna of claim 1, wherein the first region and the second region correspond to the same strip plane. The multi-frequency antenna of claim 7, wherein the second metal strip is extended to a first block metal in the second region. The multi-frequency antenna of claim 8, wherein the first block metal further comprises a first sub-block metal and a second sub-block metal, the first sub-block metal is from the first The turns of the two metal strips are expanded inwardly to form, and the second block metal is expanded outward from the turn of the second metal strip to form. The multi-frequency antenna of claim 7, wherein the resonant metal strip expands backward in the first region to a second block metal. The multi-frequency antenna according to claim 1, wherein the metal base tape, the first metal strip, the second metal strip, and the resonant metal strip of the multi-frequency antenna are disposed in an area of 55 mm*20 mm, which is more Frequency antenna system In the range of 824 MHz to 960 MHz, 1710 MHz to 1990 MHz, 824 MHz to 894 MHz, 1850 MHz to 1990 MHz, and 1920 MHz to 2170 MHz, at least five operating frequency bands are generated. The multi-frequency antenna according to claim 1, wherein the metal base tape, the first metal strip, the second metal strip, and the resonant metal strip of the multi-frequency antenna are disposed in an area of 55 mm*20 mm, which is more The frequency antenna system generates at least eight working in the range of 830MHz to 885MHz, 880MHz to 960MHz, 1710MHz to 1880MHz, 1710MHz to 2155MHz, 1749.9MHz to 1879.9MHz, 824MHz to 894MHz, 1850MHz to 1990MHz, and 1920MHz to 2170MHz, respectively. The frequency band of efficiency.