CN101447604B - Built-in antenna for digital video broadcast-handheld mobile terminal based on variable-capacitance matching circuit - Google Patents
Built-in antenna for digital video broadcast-handheld mobile terminal based on variable-capacitance matching circuit Download PDFInfo
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- CN101447604B CN101447604B CN2008102475565A CN200810247556A CN101447604B CN 101447604 B CN101447604 B CN 101447604B CN 2008102475565 A CN2008102475565 A CN 2008102475565A CN 200810247556 A CN200810247556 A CN 200810247556A CN 101447604 B CN101447604 B CN 101447604B
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Abstract
A reconfigurable built-in antenna for a digital video broadcast-handheld (DVB-H) mobile terminal capable of reconfiguration of a matching network belongs to the field of antennae design, and is characterized in that a variable-capacitance diode is added in a matching circuit printed on the front surface of a printed circuit board, the matching status of the antenna is continuously changed by continuously changing the capacitance value of the variable-capacitance diode, so as to adjust the antenna frequency and cover the required frequency bands; and a series inductor is added to reduce the maximum bias voltage required by the variable-capacitance diode. The built-in antenna has the advantages of multiple frequency bands, broad band, miniaturization, convenience for integration, and flexile control. Furthermore, the built-in antenna is suitable for various small-sized mobile terminals such as the DVB-H mobile terminal.
Description
Technical field
The present invention relates to a kind of reconfigurable antenna System Design of match circuit that is used for digital television broadcast mobile terminal, belong to the Antenna Design field of wireless communication technology.
Background technology
Digital television broadcasting (DVB-H; Digital Video Broadcast-Handheld) is the transmission standard that provides multimedia service to work out to handheld terminal through the received terrestrial digital broadcasting network that development in recent years is got up; The terminal of DVB-H has lower power consumption; Move the strong anti-interference performance that receives; Therefore this standard is applicable to miniature portable equipment such as mobile phone, GPS receiver, handheld computer through ground digital television broadcast network receiving digital television signal, and does not take band resource valuable in the mobile communications network.In recent years, along with the volume of small type mobile devices is more and more littler, and its function is become stronger day by day.How to realize on small type mobile devices that the hand-set digit TV service has become a new research focus.
For existing technology, with the antenna encapsulation that the passive device of representative is difficult to accomplish small size, because antenna will obtain good performance; Needing necessary space to guarantee how to address this problem, is the key that can portable terminal accomplish miniaturization; Mainly show following several aspect: the first, for the working frequency range 470-770MHz of DVB-H, the wavelength of free space needs 64cm at least; For traditional antenna, guarantee in mini-plant that normal operating state is impossible.The second, the bandwidth of traditional antenna is generally about 10%, and for the bandwidth 470-770MHz (48.4%) of DVB-H, the bandwidth that how to increase antenna is a challenge greatly.Tackle in these requirements, miniaturization, broadband, easy of integration, low cost are the developing direction of digital television broadcast mobile terminal antenna.Reconfigurable antenna is one of desirable scheme.
Reconfigurable antenna is through changing the physical structure of antenna itself; Like length, width, position etc., perhaps change the electrical characteristics of antenna itself, like perception, capacitive etc.; Adjust such as relevant parameters such as frequency, polarization in real time, and keep or improve the performance of original antenna.Use for DVB-H, owing to receive volume restrictions, work bandwidth is narrower owing to traditional built-in antenna.Can let antenna be issued to good performance through reconstruct, then these operating states combined, thereby satisfy the high-performance and the miniaturization requirement of antenna at the different working state.Current, a lot of about the research of reconfigurable antenna, a kind of scheme commonly used is to adopt the mode of switch switching state to realize reconstruct.For example, utilize the length of switch control antenna groove or the brachium of dipole antenna, the position of control antenna short dot, thereby the position control surface path of current of control antenna distributing point etc.; Another kind of scheme commonly used is to use variable capacitance diode to realize reconstruct, for example, utilizes variable capacitance diode to change the electrical characteristics that antenna element loads.More than various scheme to antenna volume reduce with the raising of performance bigger breakthrough is arranged all, but for the application of DVB-H service, or antenna size is bigger, or the bandwidth of antenna is narrower, is difficult to satisfy the requirement of DVB-H terminal built-in antenna.Therefore; If can design broadband (working band covers 470-770MHz at least), miniaturization, easy of integration, applicable to the reconfigurable antenna at DVB-H terminal; Not only will satisfy the development of digital TV broadcasting service; And can this antenna design method be applied to promote the development of following new business in wireless mobile communications in the mini-plant of various frequency ranges requirements.
Summary of the invention
The purpose of this invention is to provide a kind of structural design that realizes the digital television broadcast mobile terminal built-in aerial of multiband/broadband, miniaturization, easy of integration, flexible design.It has overcome the deficiency of existing reconfigurable antenna structure and performance, through the continuous adjusting to electric capacity in the antenna matching network, any operating state of antenna in required frequency band can both be mated, and reaches the purpose of spreading antenna bandwidth significantly; Co-design through to metal ground (metal shell of the regarding equipment as) structure of antenna element and antenna reaches minimizing of antenna size, and it is integrated that antenna is easy in equipment; Adopt simple printed circuit board (PCB) (PCB, printed circuit board) design match circuit, change lamped element parameter in the circuit, need not to change the design of antenna element, improved the flexibility of design according to different size, bandwidth.
The invention is characterized in, contain metal ground, feeder line, antenna element, printed circuit board (PCB) and match circuit, wherein:
Metal ground is connected with the back side of said printed circuit board (PCB), and simultaneously, this metal ground provides ground connection for said match circuit;
Feeder line, the employing impedance is 50 ohm a coaxial cable, and what link to each other with said metal ground one side is the outer conductor of said feeder line, and what link to each other with said printed circuit board (PCB) is the inner wire of said feeder line;
Antenna element; Adopt the structure of serpentine; Spatially be folded into three planes, upper, middle and lower, midplane one broadside and last plane vertical connection of broadside, another broadside is connected with the lower plane broadside is vertical; Upper and lower two planes are parallel relation, and the output of this antenna element links to each other with the input of said match circuit;
Match circuit; Be printed on the front of said printed circuit board (PCB), this match circuit contains: regulate said antenna element resonance frequency is used under the LC property matching status the 1st series inductance L1 and variable capacitance diode Cv, regulate the 2nd inductance L 2 that said antenna bandwidth of operation is used under the said LC property matching status; Shunt capacitance Cp; Capacitance Cb, the biasing resistor R1 of said variable capacitance diode Cv, wherein:
Variable capacitance diode Cv; Negative pole links to each other with said the 1st series inductance L1, and the anodal inner wire that connects said feeder line is because variable capacitance diode Cv is operated in reverse bias; Said variable capacitance diode Cv negative pole meets bias supply VCC after connecting biasing resistor R1; Through continuously changing electric capacity as the variable capacitance diode Cv of the matching capacitance of said match circuit, control the operating frequency of said antenna element under the LC matching status, make said antenna element reach coupling at any frequency place;
The 1st series inductance L1, an end links to each other with said capacitance Cb, and an end links to each other with said variable capacitance diode Cv negative pole, is used to regulate the operating frequency of said antenna element under the LC matching status, dwindles the constant interval of said variable capacitance diode Cv bias voltage;
The 2nd inductance L 2, one ends link to each other with the inner wire of said feeder line, and an end ground connection is used to change the bandwidth of operation of said antenna element under the LC matching status;
Shunt capacitance Cp, an end links to each other with said bias supply VCC, and an end ground connection is used to prevent that AC signal from getting into bias supply;
Capacitance Cb, an end links to each other with said antenna element output, and an end links to each other with said the 1st series inductance L1, is used to prevent that direct current signal from getting into antenna element.
The present invention has the advantage of multiband/broadband, miniaturization, easy of integration, flexible design, is applicable to the digital TV broadcasting service design of the various communication new technology small mobile terminals built-in aerials that are representative.
Description of drawings
Fig. 1 is the snakelike antenna system graphics of restructural based on the transfiguration coupling provided by the invention.
Fig. 2 is longitudinal sectional drawing for the A of Fig. 1 to view.
Fig. 3 is that the B of Fig. 1 is to view.
Fig. 4 is the embodiment dimensional drawing of serpentine antenna element part-structure among Fig. 1, and unit is millimeter (mm).
Fig. 5 is the embodiment dimensional drawing of the A of Fig. 1 to view structure, and unit is millimeter (mm).
Fig. 6 is that B is to the embodiment dimensional drawing of view structure and matching network circuit plate among Fig. 1, and unit is millimeter (mm).
Fig. 7 is the element sketch map of matching network.
Fig. 8 is the embodiment circuit diagram of matching network.
Fig. 9 is return loss (S11) survey map of the voltage-controlled transfiguration coupling of the embodiment of Fig. 4-Fig. 8 antenna, and 1 is VCC=0V, curve during Cv=8.86pF, and 2 is VCC=3.92V, curve during Cv=0.78pF.
Embodiment
The present invention provides a kind of built-in aerial of wideband digital television broadcasting portable terminal, and specific embodiments comprises:
Printed circuit board (PCB);
Match circuit is printed on the front of printed circuit board (PCB), comprises a series arm, a parallel branch and a biasing branch road, and series arm connects feedback point and antenna, and parallel branch connects antenna and ground, and the biasing branch road connects variable capacitance diode and ground.Contain parts in the match circuit:
Series inductance L1 is positioned at series arm, regulates the resonance frequency of antenna under the matching status, dwindles variable capacitance diode bias voltage excursion;
Series connection variable capacitance diode Cv is positioned at series arm; Regulate the resonance frequency of antenna under the matching status;
Shunt inductance L2 is positioned at parallel branch, regulates the bandwidth of operation of antenna under the matching status;
Shunt capacitance Cb is positioned at the biasing branch road, is used for AC signal ground connection, prevents that it from getting into bias supply;
Capacitance Cb is positioned at series arm, is used to prevent that direct current signal from getting into antenna element;
Power supply is for variable capacitance diode provides operating bias voltage;
Biasing resistor R1, between bias supply and variable capacitance diode, for variable capacitance diode provides bias voltage;
Antenna element, the structure of employing serpentine is folded into three faces, and as support, the length of serpentine determines the not operating frequency of reconstruct antenna with foamed plastics;
Metal ground, the back side of printed circuit board (PCB) are welded on above the metal ground, can regard the metal shell of equipment as, are equivalent to an arm (antenna element is equivalent to another arm) of dipole antenna, for match circuit ground connection are provided simultaneously;
Feeder line adopts coaxial cable, and inner wire connects the match circuit feed, outer conductor ground connection, and characteristic impedance is 50 ohm.
Like Fig. 1-shown in Figure 3, antenna system comprises metal ground 1, match circuit plate 2, feeder line 3 and antenna element 4.Metal ground 1 is connected with the back side of circuit board 2, and the front of circuit board 2 is the match circuit of printing; Feeder line 3, antenna element 4 and circuit board 2 connected modes are as shown in Figure 3, feeder line 3, and inner wire is connected with circuit board, and outer conductor is connected with metal ground; The structure of antenna element 4 is as shown in Figure 4, adopts the serpentine structure, and is flat-folded as shown in the figure at three; The connected mode of antenna element 4, feeder line 3 and each element is shown in 8 in the circuit board 2; Comprise that antenna arrives the series arm of feedback point, feedback parallel branch and variable capacitance diode Cv biasing circuit to metal ground 1, the order of connection characteristic of series arm is: antenna element->capacitance Cb->series inductance L1->variable capacitance diode Cv->feedback point; The order of connection characteristic of parallel branch is: the feedback point->shunt inductance L2->metal ground; Biasing circuit order of connection characteristic is: power supply VCC->biasing resistor R1->shunt capacitance Cp->metal ground; Wherein power supply VCC can adopt external power supply or battery.
Technical scheme of the present invention is achieved in that it is to place long antenna in less space that antenna element adopts the purpose of serpentine; The length of adjustment antenna makes it and under a suitable frequency, works (get final product between the 470-770MHz, the size operating frequency of Fig. 4 is 650MHz).The electric capacity of variable capacitance diode Cv changes with bias voltage is dull, whenever gets a capacitance and can obtain a kind of match circuit (as shown in Figure 7), and said antenna element is covered in a certain frequency band.Through choose reasonable variable capacitance diode Cv, the antenna element matching status is changed continuously and covering whole frequency (470-770MHz) through the continuous variation of Cv.
This structure specifies as follows:
At first distribute to antenna volume designing antenna unit according to portable terminal; Because the shell (metal ground) of equipment is the main body of aerial radiation; So with antenna element and shell co-design; It is operated within the reconfigurable scope, and adopting the purpose of serpentine is for dwindling the volume of antenna element as much as possible; Secondly, realize antenna element operating frequency restructural, realize the continuous variation of antenna match state, cover the frequency range of 470-770MHz, utilize simulation optimization to confirm the various elements that need through the electric capacity that changes in the match circuit; At last, matching network is designed to PCB, because circuit board has the influence of certain parasitic parameter, the element that uses in force maybe be slightly different with the element of simulation result.Matching network of the present invention can adopt prevailing digital electrical PCB manufacture craft to make.
In the implementation process of circuit board, consider to setover, at a distance from some straight factors, so need additional element such as biasing resistor, capacitance, shunt capacitance etc.Be the parasitic parameter minimum that makes circuit and the demand of antenna miniaturization, variable capacitance diode adopts 0603 encapsulation, and all the other all elements adopt 0402 encapsulation, and wiring is short as far as possible, and it is minimum, specifically as shown in Figure 8 that board area reaches.
The dielectric substrate that metal ground 1 usefulness 1.6mm is thick supports, and relative dielectric constant is 4.4 (ordinary numbers circuit board material FR4, identical with the match circuit panel material); All the other each part sizes such as Fig. 4-shown in Figure 6, unit is millimeter (mm).
Return loss test result with the antenna of Fig. 4-sized shown in Figure 6 is as shown in Figure 9, comprises the continually varying matching status among Fig. 9,, critical elements is following to the effect of antenna match in the circuit:
1. the effect of variable capacitance diode Cv
Regulate antenna in said LC matching status resonance frequency,, can reduce the antenna element resonance frequency through increasing the capacitance of Cv; Reduce the capacitance of Cv, can improve the antenna element resonance frequency;
2. the effect of series inductance L1
Regulate antenna in said LC matching status resonance frequency,, can reduce the antenna element resonance frequency through increasing the inductance value of L1; Reduce the inductance value of L1, can improve the antenna element resonance frequency; Dwindle variable capacitance diode Cv and cover the required bias voltage scope of whole frequency, reduce required maximum bias voltage;
3. the effect of shunt inductance L2
Adjust antenna at said LC matching status bandwidth of operation, the value of L2 and the dullness of the correlation right and wrong between the bandwidth of operation, existing an optimum point, component value departs from after the optimum, and matching state all can worsen.
Through optimizing; The component value that obtains the antenna match of suitable embodiment size of the present invention is: L1=15 nanohenry (nH); L2=22 nanohenry (nH), Cv=0.78~8.86 pico farads (pF), capacitance Cb are 47 pico farads (pF); Shunt capacitance Cp is 100 pico farads (pF), and biasing resistor R1 is 2.2 kilohms.As shown in Figure 9, return loss≤-10dB can cover the digital television broadcasting frequency range of whole 470-770MHz.
Match circuit of the present invention not only can be applied in the digital television broadcasting small mobile terminals; Also can be used for the reconstruct of other professional portable terminal built-in aerial; Circuit does not receive the restriction of equipment volume, can mate antenna in each different frequency range, switches with switch then.So the present invention is highly suitable for the design of broadband, the built-in interior lines of portable terminal, miniaturization.
Claims (1)
1. be used for the reconfigurable built-in aerial of matching network of digital television broadcast mobile terminal, it is characterized in that: contain metal ground, feeder line, antenna element, printed circuit board (PCB) and match circuit, wherein:
Metal ground is connected with the back side of said printed circuit board (PCB), and simultaneously, this metal ground provides ground connection for said match circuit;
Feeder line, the employing impedance is 50 ohm a coaxial cable, and what link to each other with said metal ground one side is the outer conductor of said feeder line, and what link to each other with said printed circuit board (PCB) is the inner wire of said feeder line;
Antenna element; Adopt the structure of serpentine; Spatially be folded into three planes, upper, middle and lower, midplane one broadside and last plane vertical connection of broadside, another broadside is connected with the lower plane broadside is vertical; Upper and lower two planes are parallel relation, and the output of this antenna element links to each other with the input of said match circuit;
Match circuit; Be printed on the front of said printed circuit board (PCB), this match circuit contains: regulate said antenna element resonance frequency is used under the LC property matching status the 1st series inductance (L1) and variable capacitance diode (Cv), regulate the 2nd inductance (L2) that said antenna element bandwidth of operation is used under the said LC property matching status; Shunt capacitance (Cp); Capacitance (Cb), the biasing resistor (R1) of said variable capacitance diode (Cv), wherein:
Variable capacitance diode (Cv); Negative pole links to each other with said the 1st series inductance (L1); The anodal inner wire that connects said feeder line; Because variable capacitance diode (Cv) is operated in reverse bias, said variable capacitance diode (Cv) negative pole connects bias supply (VCC) after connecting biasing resistor (R1), through continuously changing the electric capacity as the variable capacitance diode (Cv) of the matching capacitance of said match circuit; Control the operating frequency of said antenna element under the LC matching status, make said antenna element reach coupling at any frequency place;
The 1st series inductance (L1); One end links to each other with said capacitance (Cb); One end links to each other with said variable capacitance diode (Cv) negative pole, is used to regulate the operating frequency of said antenna element under the LC matching status, dwindles the constant interval of said variable capacitance diode (Cv) bias voltage;
The 2nd inductance (L2), an end links to each other with the inner wire of said feeder line, and an end ground connection is used to change the bandwidth of operation of said antenna element under the LC matching status;
Shunt capacitance (Cp), an end links to each other with said bias supply (VCC), and an end ground connection is used to prevent that AC signal from getting into bias supply;
Capacitance (Cb), an end links to each other with said antenna element output, and an end links to each other with said the 1st series inductance (L1), is used to prevent that direct current signal from getting into antenna element.
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CN101447604B true CN101447604B (en) | 2012-07-18 |
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CN102484497B (en) * | 2010-08-11 | 2014-06-04 | 株式会社村田制作所 | Frequency-stabilizing circuit, antenna apparatus and communication terminal device |
JP5656108B2 (en) * | 2010-10-15 | 2015-01-21 | 三菱マテリアル株式会社 | Antenna device substrate and antenna device |
CN103185838B (en) * | 2011-12-29 | 2016-06-15 | 国民技术股份有限公司 | A kind of method of measuring coil antenna match capacitance parameter |
CN102610931A (en) * | 2012-04-10 | 2012-07-25 | 上海华勤通讯技术有限公司 | Frequency range adjustable antenna and frequency range adjustable antenna system and mobile terminal |
CN104993235B (en) * | 2015-06-12 | 2019-01-15 | 联想(北京)有限公司 | A kind of antenna assembly and electronic equipment |
CN105742818A (en) * | 2016-03-25 | 2016-07-06 | 联想(北京)有限公司 | Antenna and control method |
CN109637788A (en) * | 2018-12-29 | 2019-04-16 | 厦门英诺迅科技有限公司 | A kind of voltage-controlled variable inductance |
CN113644405B (en) * | 2021-08-10 | 2023-12-29 | 苏州无双医疗设备有限公司 | Implantable medical equipment |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5874926A (en) * | 1996-03-11 | 1999-02-23 | Murata Mfg Co. Ltd | Matching circuit and antenna apparatus |
CN1368766A (en) * | 2001-02-07 | 2002-09-11 | 松下电器产业株式会社 | Antenna equipment |
US6469590B1 (en) * | 2000-06-20 | 2002-10-22 | Shakespeare Company | Marine antenna with an integral filter |
-
2008
- 2008-12-30 CN CN2008102475565A patent/CN101447604B/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5874926A (en) * | 1996-03-11 | 1999-02-23 | Murata Mfg Co. Ltd | Matching circuit and antenna apparatus |
US6469590B1 (en) * | 2000-06-20 | 2002-10-22 | Shakespeare Company | Marine antenna with an integral filter |
CN1368766A (en) * | 2001-02-07 | 2002-09-11 | 松下电器产业株式会社 | Antenna equipment |
Non-Patent Citations (2)
Title |
---|
Libo Huang, etc..Coexistence of an Electrically Tunable DVB-H Antenna with the GSM Transmitter in a Mobile Phone.《Microwave Symposium,2007.IEEE/MTT-S International》.2007,255-258页. * |
M.Komulainen,etc..Compact varactor-tuned meander line monopole antenna for DVB-H signal reception.《Electronics Letters》.2007,第43卷(第24期),1324-1326页. * |
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