CN111509366A - Hand-held terminal - Google Patents

Hand-held terminal Download PDF

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Publication number
CN111509366A
CN111509366A CN201911342428.3A CN201911342428A CN111509366A CN 111509366 A CN111509366 A CN 111509366A CN 201911342428 A CN201911342428 A CN 201911342428A CN 111509366 A CN111509366 A CN 111509366A
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China
Prior art keywords
metal
metal strip
switch
antenna
bottom frame
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CN201911342428.3A
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Chinese (zh)
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CN111509366B (en
Inventor
朱玉飞
郑磊
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AAC Technologies Pte Ltd
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AAC Technologies Pte Ltd
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00Details of, or arrangements associated with, antennas
    • H01Q1/12Supports; Mounting means
    • H01Q1/22Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • H01Q1/243Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with built-in antennas
    • H01Q1/244Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use with built-in antennas extendable from a housing along a given path

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Waveguide Aerials (AREA)
  • Support Of Aerials (AREA)
  • Telephone Set Structure (AREA)

Abstract

The invention relates to the technical field of wireless, and provides a handheld terminal which comprises a metal middle frame, wherein the metal middle frame comprises two opposite side frames and a bottom frame connected with the two side frames, the mobile terminal also comprises a main board close to the bottom frame and a metal slot antenna, the bottom frame is provided with a first broken joint and a second broken joint which cut off the bottom frame, the joint of the bottom frame and one of the side frames is provided with a third broken joint, the second broken joint is positioned between the first broken joint and the third broken joint, the bottom frame between the first broken joint and the second broken joint forms a first metal strip, and the bottom frame between the second broken joint and the third broken joint forms a second metal strip; and the main board is provided with a feed point, a grounding point, a main board reference ground, a first switch and a second switch for controlling the tuning switching of the metal slot antenna. The invention improves the performance of the low-frequency left-handed antenna.

Description

Hand-held terminal
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of wireless, in particular to a handheld terminal.
[ background of the invention ]
Mobile terminals with metal casings, such as smart phones, are becoming more and more mainstream, and meanwhile, the design of antennas by using metal casing frames is becoming the current popular trend, and metal frame slot antennas form antennas of terminals by using cell phone frame slots and feed circuits.
[ summary of the invention ]
The invention provides a handheld terminal, aiming at the problem that the antenna performance is reduced when the terminal is held by a hand in the antenna scheme in the prior art.
A handheld terminal comprises a metal middle frame, wherein the metal middle frame comprises two opposite side frames and a bottom frame connected with the two side frames, the mobile terminal further comprises a main board close to the bottom frame and a metal slot antenna, a first broken joint and a second broken joint which are used for cutting off the bottom frame are arranged on the bottom frame, a third broken joint is arranged at the joint of the bottom frame and one of the side frames, the second broken joint is positioned between the first broken joint and the third broken joint, a first metal strip is formed by the bottom frame between the first broken joint and the second broken joint, and a second metal strip is formed by the bottom frame between the second broken joint and the third broken joint; the main board is provided with a feeding point, a grounding point, a main board reference ground, a first switch and a second switch, wherein the first switch and the second switch are used for controlling the tuning switching of the metal slot antenna; the metal slot antenna also comprises a radiation piece which is opposite to the first metal strip at intervals and is close to the second broken seam, and the radiation piece is connected with the main board reference ground through the grounding point; the first metal strip and the radiation sheet are connected with the feed point, and the first metal strip, the second metal strip and the radiation sheet are radiation bodies of the metal slot antenna.
Preferably, the mainboard is further provided with a first switch connection point connected with the first switch and a second switch connection point connected with the second switch, and the metal slot antenna further comprises a first elastic pin connected with the first switch connection point and the first metal strip and a second elastic pin connected with the second switch connection point and the second metal strip.
Preferably, the metal slot antenna further comprises a second radiation sheet opposite to the second metal strip at intervals, and the second radiation sheet is electrically connected to the second elastic pin.
Preferably, the metal slot antenna further includes a third spring leg connecting the radiation plate and the ground point, and a fourth spring leg connecting the radiation plate and the feed point.
Preferably, when the second switch is switched to the short-circuit state, the second metal strip is in a connection state with the main board in reference, the second metal strip, the first metal strip and the radiating sheet are coupled with each other to generate medium-high frequency resonance, and the antenna resonance covers the medium-high frequency band by switching different state tuning through the first switch.
Preferably, when the second switch is switched to the open-circuit state, the second metal strip and the motherboard are in the off state with reference, the first metal strip and the radiating sheet are used as radiators of the antenna, and the first switch switches different antenna states to tune, so that the antenna resonates and covers a low frequency band.
Preferably, the radiation sheet is a metal antenna pattern formed by using a laser-Direct-structuring (L aser-Direct-structuring, L DS) or a Flexible Printed Circuit (FPC) process.
Preferably, handheld terminal still includes a plastic body, the metal center passes through mould internal injection moulding, just first metal strip, second metal strip inlay and locate in the plastic body.
Compared with the prior art, the side wall of the metal frame is broken into three broken joints to form two independent metal strips, and the metal strips and the radiation sheet are tuned and switched through the two switches, so that the antenna performance of the handheld terminal held by a hand at a low frequency is improved while the medium-high frequency performance is ensured.
[ description of the drawings ]
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:
fig. 1 is a schematic structural diagram of a terminal and a metal slot antenna according to an embodiment of the present invention;
FIG. 2 is a schematic structural view of a portion of the structure shown in FIG. 1;
FIG. 3 is a schematic front view, partially broken away, of the partial structure shown in FIG. 1;
FIG. 4 is a schematic backside view of a portion of the structure shown in FIG. 1;
FIG. 5 is a schematic structural diagram of the radiation plate shown in FIG. 2;
fig. 6 is a schematic structural view of a second radiation sheet shown in fig. 2;
fig. 7 is a schematic structural diagram of a terminal including a plastic body according to an embodiment of the present invention;
FIG. 8 is the FS, BHH L, BHHR performance data in the state 1 provided by the first embodiment of the present invention;
FIG. 9 shows the performance data of FS, BHH L, and BHHR in state 2 according to an embodiment of the present invention;
fig. 10 is comparative data of the L TE B8 frequency band and the antenna FS performance in the state 1 and the state 2 according to the first embodiment of the present invention;
fig. 11 is comparative data of the L TE B8 frequency band and the antenna BHH L performance in the state 1 and the state 2 according to the first embodiment of the present invention;
FIG. 12 is comparative data of L TE B8 frequency band and antenna BHHR performance in state 1 and state 2 provided by the first embodiment of the present invention;
fig. 13 is comparative data of the L TE B7 frequency band and the antenna FS performance in the state 1 and the state 2 according to the first embodiment of the present invention;
fig. 14 is comparative data of the L TE B7 frequency band and the antenna BHH L performance in the state 1 and the state 2 according to the first embodiment of the present invention;
FIG. 15 is comparative data of the L TE B7 frequency band and antenna BHHR performance in the state 1 and the state 2 according to the first embodiment of the present invention.
[ detailed description ] embodiments
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Please refer to fig. 1 to 4. The invention provides a handheld terminal 100, wherein the handheld terminal 100 comprises a metal middle frame 10, the metal middle frame 10 comprises two opposite side frames 11 and a bottom frame 12 connecting the two side frames 11, the handheld terminal 100 further comprises a main board 20 adjacent to the bottom frame 12 and a metal slot antenna, and the handheld terminal is characterized in that a first broken seam 121 and a second broken seam 122 for cutting off the bottom frame are arranged on the bottom frame 12, a third broken seam 123 is arranged at a joint of the bottom frame 12 and one of the side frames 11, specifically, the joint of the bottom frame 12 and one of the side frames 11 is a position for holding the terminal by a hand, and the joint can be a joint with any side edge, namely a left-hand holding position or a right-hand holding position. In the present embodiment, the third slit 123 is provided at the left-hand grip.
The second broken joint 122 is located between the first broken joint 121 and the third broken joint 123, a bottom frame between the first broken joint 121 and the second broken joint 122 forms the first metal strip 31, and a bottom frame between the second broken joint 122 and the third broken joint 123 forms the second metal strip 32; a feeding point 41, a grounding point 42, a main board reference ground, and a first switch and a second switch for controlling the tuning switching of the metal slot antenna are arranged on the main board 20; the metal slot antenna further comprises a radiation piece 61 which is opposite to the first metal strip 31 at a spacing and is adjacent to the second broken seam 122, and the radiation piece 61 is connected with a main board reference ground through the grounding point 42; the first metal strip 31 and the radiation sheet 61 are connected to the feeding point 41, and the first metal strip 31, the second metal strip 32 and the radiation sheet 61 are radiators of the metal slot antenna.
The main board 20 is further provided with a first switch connection point 51 connected to the first switch 512 and a second switch connection point 52 connected to the second switch 522, and the metal slot antenna further includes a first spring leg 511 connected to the first switch connection point 51 and the first metal strip 31 and a second spring leg 521 connected to the second switch connection point 52 and the second metal strip 32.
Specifically, in this embodiment, the metal slot antenna further includes a second radiation plate 62 opposite to the second metal strip 32 at an interval, and the second radiation plate 62 is electrically connected to the second elastic pin 521. The second radiation sheet 62 is used to enhance the radiation effect, and when the structure of the second metal strip 32 is sufficient to meet the performance requirement, the second radiation sheet 62 can be eliminated.
The metal slot antenna further includes a third spring leg 421 connecting the radiation sheet 61 and the ground point 42, and a fourth spring leg 411 connecting the radiation sheet 61 and the feeding point 41, please refer to fig. 5 and 6 together, which are schematic structural diagrams of the radiation sheet 61, the radiation sheet 61 includes a radiation metal sheet 611, a ground terminal 612 for connecting the third spring leg 421, and a feeding terminal 613 for connecting the fourth spring leg 411, the structure of the second radiation sheet 62 is as shown in fig. 6, the second radiation sheet 62 includes a radiation metal sheet 621 and a ground terminal 622 for connecting the second spring leg 521, and the radiation sheet 61 and the second radiation sheet 62 are metal antenna patterns formed by a laser Direct molding (L aser-Direct-structuring, L DS) or a flexible Circuit board (FPC) process.
Referring to fig. 7, the handheld terminal 100 further includes a plastic body 70, the metal middle frame is formed by in-mold injection molding, the first metal strip 31 and the second metal strip 32 are embedded in the plastic body 70, and the plastic body is filled with the first broken seam 121, the second broken seam 122 and the third broken seam 123.
Referring again to fig. 1 to 4, when the metal slot antenna is in operation, the first metal strip 31, the second metal strip 32 and the radiating plate 61 are used as radiators of the antenna, and tuning is performed through the first switch and the second switch. When the second switch is switched to a short-circuit state, the second metal strip 32 and the mainboard reference ground are in a connection state, the second metal strip 32, the first metal strip 31 and the radiation sheet 61 are coupled with each other to generate medium-high frequency resonance, and different states are switched through the first switch to be tuned, so that the antenna resonance covers a medium-high frequency band. When the second switch is switched to the open-circuit state, the second metal strip 32 and the motherboard reference ground are in the off state, the first metal strip 31 and the radiating sheet 61 are used as radiators of the antenna, and different antenna states are switched by the first switch to tune, so that the antenna resonance covers a low frequency band.
Specifically, when the antenna works in a medium-high frequency band (1710-2690 MHz), the second metal strip and the mainboard are in a connection state with reference through the second switch, and the second metal strip, the first metal strip and the radiation sheet are coupled with each other to generate medium-high frequency resonance. Different antenna states are switched and tuned through the first switch, so that the antenna resonance can cover a middle and high frequency band (1710-2690 MHz).
When the antenna works in a low frequency band (699-960 MHz), the second metal strip and the mainboard reference ground are in an off state through the second switch, and when the second metal strip and the mainboard reference ground are in the off state, the first metal strip and the radiating sheet are used as main radiating bodies of the antenna, different antenna states are switched through the first switch for tuning, and the antenna resonance can cover the low frequency band (699-960 MHz). In this state, when the user holds the radiation sheet, the second metal strip is relatively close to the hand, but the coupling effect between the radiation sheet and the first metal strip is small. At this time, the first metal strip and the radiating sheet are used as main radiators of the antenna, the position of the first metal strip and the radiating sheet is relatively far away from the hand, and the energy absorbed by the hand is relatively small, so that the performance loss of the antenna is correspondingly reduced when the antenna is held by the left hand.
Referring to fig. 8 and fig. 9, in the embodiment, the passive performance of the antenna in the L TE B8 low band is compared with that in the L TE B7 high band:
the data shown in fig. 8 is data of state 1, where state 1 means: the second switch is switched in a closed state from the first switch-15 nH to the ground; where nH is the inductance unit nanohenry.
The data shown in fig. 9 is data of state 2, and state 2 means: at the first switch-15 nH to ground, the second switch switches the data in the open state.
The following data in the passive test state are shown in detail in fig. 8 and 9:
FS performance, as indicated by curve F in fig. 8 and 9, FS refers to Free Space (FS), i.e. The antenna performance of The mobile phone in The Over The Air (OTA) state;
BHH L performance as indicated by curve L in fig. 8 and 9, BHH L refers to the left-Hand held state (Beside Head and Hand L eft Side, BHH L), i.e., the antenna performance of the handset held by the Head and left Wide Hand (Wide Hand) of the american Association for wireless communication and internet Association (citia) specifications;
BHHR performance: as indicated by the curve R in fig. 8 and 9, BHHR refers to the Right Hand held state (BHHR), i.e. the antenna performance of the handset held by the Head and the Right Wide Hand (Wide Hand) of the citia specification.
Referring to fig. 10 to 12, for a comparison of the L TE B8 frequency band, the FS performance, the BHH L performance and the BHHR performance in the passive antenna state 1 and state 2, respectively, the average efficiency is shown in table 1:
table 1:
Figure BDA0002331823550000071
as can be seen from Table 1 above, the BHH L performance of the low frequency B8 of State 2 is improved by about 1.2dB over that of State 1.
Referring to fig. 13 to fig. 15, the average efficiency of the comparison of the FS performance, the BHH L performance and the BHHR performance in the state 1 and the state 2 under the passive condition of the L TE B7 band antenna is shown in table 2:
table 2:
Figure BDA0002331823550000072
as can be seen from the above Table 2, the FS, BHH L and BHHR performances of the high frequency B7 of State 1 were improved by about 1.7dB, 0.7dB and 1.9dB, respectively, compared to State 2.
Compared with the prior art, the side wall of the metal frame is broken into three broken joints to form two independent metal strips, and the metal strips and the radiation sheet are tuned and switched through the two switches, so that the performance of the antenna held by a low-frequency hand is improved while the medium-high frequency performance is ensured.
While the foregoing is directed to embodiments of the present invention, it will be understood by those skilled in the art that various changes may be made without departing from the spirit and scope of the invention.

Claims (8)

1. A handheld terminal comprises a metal middle frame, wherein the metal middle frame comprises two opposite side frames and a bottom frame connected with the two opposite side frames, the mobile terminal further comprises a main board close to the bottom frame and a metal slot antenna, and the handheld terminal is characterized in that a first broken joint and a second broken joint which are used for cutting off the bottom frame are arranged on the bottom frame, a third broken joint is arranged at the joint of the bottom frame and one of the side frames, the second broken joint is positioned between the first broken joint and the third broken joint, a first metal strip is formed by the bottom frame between the first broken joint and the second broken joint, and a second metal strip is formed by the bottom frame between the second broken joint and the third broken joint; the main board is provided with a feeding point, a grounding point, a main board reference ground, a first switch and a second switch, wherein the first switch and the second switch are used for controlling the tuning switching of the metal slot antenna; the metal slot antenna also comprises a radiation piece which is opposite to the first metal strip at intervals and is close to the second broken seam, and the radiation piece is connected with the main board reference ground through the grounding point; the first metal strip and the radiation sheet are connected with the feed point, and the first metal strip, the second metal strip and the radiation sheet are radiation bodies of the metal slot antenna.
2. The handheld terminal according to claim 1, wherein the main board further has a first switch connection point connected to the first switch and a second switch connection point connected to the second switch, and the metal slot antenna further includes a first spring pin connecting the first switch connection point and the first metal strip and a second spring pin connecting the second switch connection point and the second metal strip.
3. The handheld terminal of claim 2, wherein the metal slot antenna further comprises a second radiating patch spaced apart from and opposing the second metal strip, and wherein the second radiating patch is electrically connected to the second pogo pin.
4. The handheld terminal of claim 1, wherein the metal slot antenna further comprises a third spring leg connecting the radiating patch to the ground point and a fourth spring leg connecting the radiating patch to the feed point.
5. The handheld terminal according to any one of claims 1 to 4, wherein when the second switch is switched to the short-circuit state, the second metal strip is in a connection state with the main board reference ground, the second metal strip, the first metal strip and the radiating patch are coupled to each other to generate a medium-high frequency resonance, and the first switch switches to different state tuning, so that the antenna resonance covers the medium-high frequency band.
6. The handheld terminal according to any one of claims 1 to 4, wherein when the second switch is switched to an open circuit state, the second metal strip is in an open state with reference to the main board, the first metal strip and the radiating patch are used as radiators of the antenna, and the first switch switches different antenna states to tune so that the antenna resonates to cover a low frequency band.
7. The handheld terminal of claim 1, wherein the radiation patch is a metal antenna pattern formed using a laser-Direct-structuring (L ase-Direct-structuring, L DS) or a Flexible Printed Circuit (FPC) process.
8. The metal slot antenna of claim 1, wherein the handheld terminal further comprises a plastic body, the metal middle frame is formed by in-mold injection molding, and the first metal strip and the second metal strip are embedded in the plastic body.
CN201911342428.3A 2019-12-23 2019-12-23 Hand-held terminal Expired - Fee Related CN111509366B (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004112187A1 (en) * 2003-06-19 2004-12-23 International Business Machines Corporation Antennas integrated within the metallic display frame of a computing device
CN107645040A (en) * 2016-07-21 2018-01-30 深圳富泰宏精密工业有限公司 Antenna structure and the radio communication device with the antenna structure
US10008763B2 (en) * 2014-12-09 2018-06-26 Pegatron Corporation Multi-band antenna
CN109088155A (en) * 2018-08-26 2018-12-25 昆山亿趣信息技术研究院有限公司 A kind of antenna system promoting diversity antenna performance
CN109560386A (en) * 2017-09-27 2019-04-02 深圳富泰宏精密工业有限公司 Antenna structure and wireless communication device with the antenna structure
CN208835266U (en) * 2018-08-03 2019-05-07 瑞声精密制造科技(常州)有限公司 Antenna system and mobile terminal

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004112187A1 (en) * 2003-06-19 2004-12-23 International Business Machines Corporation Antennas integrated within the metallic display frame of a computing device
US10008763B2 (en) * 2014-12-09 2018-06-26 Pegatron Corporation Multi-band antenna
CN107645040A (en) * 2016-07-21 2018-01-30 深圳富泰宏精密工业有限公司 Antenna structure and the radio communication device with the antenna structure
CN109560386A (en) * 2017-09-27 2019-04-02 深圳富泰宏精密工业有限公司 Antenna structure and wireless communication device with the antenna structure
CN208835266U (en) * 2018-08-03 2019-05-07 瑞声精密制造科技(常州)有限公司 Antenna system and mobile terminal
CN109088155A (en) * 2018-08-26 2018-12-25 昆山亿趣信息技术研究院有限公司 A kind of antenna system promoting diversity antenna performance

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