The reconfigurable embedded in mobile phone loop antenna of short dot
Technical field
The invention belongs to the Antenna Design field of wireless communication technology, relate to the reconfigurable embedded in mobile phone loop antenna of a kind of short dot.
Background technology
Along with the develop rapidly of wireless communication technology, the function of mobile phone is progressively expanded, from before single speech business develop into current numeral, multimedia service.Integrated multiple business is one of important trend of current phone development on same mobile phone.Because the frequency band range of various wireless communication vocational work is not quite similar; Such as global system for mobile communications (GSM850:824-894MHz; GSM900:880-960MHz), global positioning system (GPS:1575MHz), Digital Cellular System (DCS:1710-1880MHz); PCS Personal Communications System (PCS:1850-1990MHz), UMTS (UMTS:1920-2170MHz) and bluetooth (Bluetooth:2.4GHz) etc.Need realize that on existing antenna for mobile phone more frequency band satisfies the multiple business demand.Therefore, multiband antenna becomes the main target of mobile terminal antenna design.
Antenna sends, accepts electromagnetic device as mobile phone, and its performance has directly determined the performance of whole cell phone system.The enough spaces of the performance need of antenna guarantee.In the design of antenna for mobile phone, adopt the structure of multiple-limb usually, corresponding one or more frequency band of each branch.The increase of branch will inevitably increase the size of antenna, and original space can't guarantee the operate as normal of antenna.Simultaneously, miniaturization is the trend of modern mobile phones design, and mobile phone in light weight, thin thickness has the very strong market competitiveness.Therefore, the demand of miniaturization has further increased the design difficulty of multiband antenna for mobile phone.
The reconfigurable antenna technology is one of effective technology that solves in the space.Its basic thought is a notion of utilizing antenna structure multiplexing, on the basis of original antenna work, utilizes the structure of element change antennas such as switch, forms other a kind of mode of operation, unites original mode of operation, realizes the covering of a plurality of frequency bands.The more important thing is that antenna volume does not increase.The element of introducing can be introduced the loss of some antenna performances, and the loss that is equivalent to partial properties exchanges the number of frequency bands of antenna for.Evidence is that to adopt the restructural technology in the portable terminal of representative be feasible at mobile phone.
Summary of the invention
In order to overcome the deficiency of above-mentioned prior art; The object of the present invention is to provide the reconfigurable embedded in mobile phone loop antenna of a kind of short dot,, realize two kinds of mode of operations through changing the position of antenna body short dot; Under the prerequisite that does not increase the antenna system space; Realize the covering of multiple business frequency band, satisfied the trend of current antenna miniaturization simultaneously, had the characteristics of miniaturization, broadband, multiband.
To achieve these goals, the technical scheme of the present invention's employing is:
The reconfigurable embedded in mobile phone loop antenna of short dot; Contain metal conductor portion, first PIN diode 6 and second PIN diode 7; Said metal conductor portion comprises antenna body 1, feed minor matters 2, the first short circuit minor matters 3, the second short circuit minor matters 4 and frequency modulation sheet metal 5, wherein:
Antenna body 1 adopts the form of puckered ring antenna; It is folding to carry out inside an angle of 90 degrees according to planar structure along first track 8, second track 9 and the 3rd track 10, realizes two kinds of mode of operations through the ground state that changes said first short circuit minor matters 3 and the said second short circuit minor matters 4;
Feed minor matters 2 are connected with said antenna body 1, are connected with the distributing point of cell phone mainboard, as signal input part;
The first short circuit minor matters, 3, one ends are connected with said antenna body 1, and the other end is connected with the ground of cell phone mainboard through said first PIN diode 6;
The second short circuit minor matters, 4, one ends are connected with said antenna body 1, and the other end is connected with the ground of cell phone mainboard through said second PIN diode 7;
Frequency modulation sheet metal 5 is connected with said antenna body 1, is used to regulate the frequency of two kinds of mode of operations of antenna;
First PIN diode 6; The ground that connects said first short circuit minor matters 3 and said cell phone mainboard; During said first PIN diode, 6 conductings; The said first short circuit minor matters 3 are connected with the ground of said cell phone mainboard, and when said first PIN diode 6 broke off, the ground of said first short circuit minor matters 3 and said cell phone mainboard broke off.
Second PIN diode 7; The ground that connects said second short circuit minor matters 4 and said cell phone mainboard; During said second PIN diode, 7 conductings; The said second short circuit minor matters 4 are connected with the ground of said cell phone mainboard, and when said second PIN diode 7 broke off, the ground of said second short circuit minor matters 4 and said cell phone mainboard broke off.
Two kinds of mode of operations of wherein said antenna body 1 are meant:
When 6 conductings of said first PIN diode, said second PIN diode 7 breaks off when leading to, and said antenna body 1 works in ring first pattern;
When 6 disconnections of said first PIN diode, when said second PIN diode 7 broke conducting, said antenna body 1 worked in ring second pattern;
Amount to and produce two kinds of mode of operations.。
Wherein, the planar structure of said antenna body 1 is the I-shaped loop aerial, and frequency modulation sheet metal 5 is connected in the first horizontal edge 1a outside of said I-shaped loop aerial; Feed minor matters 2, the first short circuit minor matters 3 and the second short circuit minor matters 4 all are connected in the 4th horizontal edge 1d outside of said I-shaped loop aerial, and the position of the first short circuit minor matters 3 is between the feed minor matters 2 and the second short circuit minor matters 4, and first track 8 is meant the outer side edges of the first horizontal edge 1a; Second track 9 refers to the inner side edge of the second horizontal edge 1b; The 3rd track 10 refers to the inner side edge of the 3rd horizontal edge 1c, after folding, and the first horizontal edge 1a and plane, second horizontal edge 1b place; Relative with the 3rd horizontal edge 1c with the 4th horizontal edge 1d place plane parallel; And all the vertical edge 1e with the I-shaped loop aerial is vertical, and plane, frequency modulation sheet metal 5 place is parallel with vertical edge 1e, and frequency modulation sheet metal 5 contacts with the 4th horizontal edge 1d.
The on off operating mode of said first PIN diode 6 and second PIN diode 7 is by a kind of digital integrated circuit chip control of switch control usefulness, for example PIC18LF2525.
The present invention has miniaturization, broadband, multiband and is easy to integrated advantage, is applicable to the various small mobile terminals built-in aerial designs with the mobile phone representative.
Description of drawings
Fig. 1 is an embedded in mobile phone loop antenna plane graph provided by the invention.
Fig. 2 is the graphics after antenna folds among Fig. 1.
Fig. 3 is the embodiment dimensional drawing after antenna is installed among Fig. 1, and unit is millimeter (mm).
Fig. 4 is the embodiment end view after antenna is installed among Fig. 1, and unit is a millimeter (mm).
Fig. 5 is the measurement of reflection-factor figure that antenna is installed the back embodiment among Fig. 1:
first pattern;
second pattern.
Fig. 6 is the efficiency measurement figure that antenna is installed the back embodiment among Fig. 1:
first pattern;
second pattern.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is explained further details.
As shown in Figure 1; Plane graph for the reconfigurable embedded in mobile phone loop antenna of short dot according to the invention; First PIN diode 6 and second PIN diode 7; Said metal conductor portion comprises antenna body 1, feed minor matters 2, the first short circuit minor matters 3, the second short circuit minor matters 4 and frequency modulation sheet metal 5, and the planar structure of antenna body 1 is the I-shaped loop aerial, and frequency modulation sheet metal 5 is connected in first horizontal edge, the 1 a outside of said I-shaped loop aerial; Feed minor matters 2, the first short circuit minor matters 3 and the second short circuit minor matters 4 all are connected in the 4th horizontal edge 1d outside of said I-shaped loop aerial, and the position of the first short circuit minor matters 3 is between the feed minor matters 2 and the second short circuit minor matters 4.
As shown in Figure 2, be that antenna body among Fig. 11 adopts the form of folding (perhaps crooked) loop antenna, it is folding to carry out inside an angle of 90 degrees according to planar structure along first track 8, second track 9 and the 3rd track 10; Form a cuboid, inner by foam or plastic support, be the final application form of said antenna system; First track 8 is meant the outer side edges of the first horizontal edge 1a, and second track 9 refers to the inner side edge of the second horizontal edge 1b, and the 3rd track 10 refers to the inner side edge of the 3rd horizontal edge 1c; After folding; The first horizontal edge 1a and plane, second horizontal edge 1b place, relative with the 3rd horizontal edge 1c with the 4th horizontal edge 1d place plane parallel, and all the vertical edge 1e with the I-shaped loop aerial is vertical; Plane, frequency modulation sheet metal 5 place is parallel with vertical edge 1e, and frequency modulation sheet metal 5 contacts with the 4th horizontal edge 1d.
Like Fig. 3 and shown in Figure 4, be the enforcement illustration after the antenna installation among Fig. 1, cell phone mainboard 11 adopts the thick medium substrate of 1mm, and relative dielectric constant is 4.4.Cell phone mainboard 11 back sides are metal ground, and material is a copper.Antenna system is installed on the front of cell phone mainboard 11.First PIN diode, 6 one ends are connected with short circuit minor matters 3, and an end is connected with metal ground through through hole; Second PIN diode, 7 one ends are connected with short circuit minor matters 4, and an end is connected with metal ground through through hole.The biasing circuit of first PIN diode 6 and second PIN diode 7 is printed in the front of cell phone mainboard 11.Biasing circuit comprises distributing point 12, the first capacitance C
B1, the second capacitance C
B2, the 3rd capacitance C
B3, the first choke induction L
B1, the second choke induction L
B2, the first biasing resistor R
B1, the second biasing resistor R
B2, the ac short circuit inductance L
s, first bias voltage input, 13 and first bias voltage input 14.Feed minor matters 2 and the 3rd capacitance C
B3Link to each other.Distributing point 12 is by 50 ohm of designs of characteristic impedance, and the input 13 of first bias voltage and second bias voltage are imported 14 and be connected with digital integrated circuit chip, and PIC18LF2525 for example controls the on off operating mode of first PIN diode 6 and second PIN diode 7.
Technical scheme of the present invention is achieved in that working as first PIN diode 6 is conducting state, and second PIN diode 7 is an off-state, and the first short circuit minor matters 3 are connected with metal ground, and the second short circuit minor matters 4 are broken off with metal ground, and antenna body 1 works in first pattern.When first PIN diode 6 is an off-state; Second PIN diode 7 is a conducting state; The first short circuit minor matters 3 are broken off with metal ground, and the second short circuit minor matters 4 are connected with metal ground, and antenna body 1 works in second pattern; Because the length of main body antenna 1 is less than the length of main body antenna 1 shown in first pattern shown in second pattern, the resonance frequency of second pattern is higher than the resonance frequency of first pattern.Under first pattern and second pattern, antenna body 1 works in the loop antenna pattern, and the loop antenna pattern comprises three resonance frequencys: first frequency, second frequency and the 3rd frequency.Wherein second frequency and the 3rd frequency are about 2 times and 3 times of first frequency, change first frequency through the length of regulating antenna body 1.Frequency modulation sheet metal 5 can change first frequency and the 3rd frequency, keeps second frequency constant, through regulating the size of frequency modulation sheet metal 5, can second frequency and the 3rd frequency accent be covered high band together, covers low-frequency range with first frequency.The resonance frequency of comprehensive two kinds of patterns can realize the covering of a plurality of frequency bands.
The structure of this inventive embodiment specifies as follows:
The practical implementation size is by Fig. 3 and shown in Figure 4; Bias voltage according to said first PIN diode 6 and second PIN diode, 7 conducting needs designs said biasing circuit at last, and the said biasing circuit component value that is fit to embodiment size of the present invention is: L
B1=120 nanohenrys, L
B2=120 nanohenrys, L
s=100 nanohenrys, C
B1=120 pico farads, C
B2=120 pico farads, C
B3=120 pico farads, R
B1=46 ohm, R
B2=46 ohm.Reflection coefficient test result with the antenna of Fig. 3, sized shown in Figure 4 is as shown in Figure 5, and wherein said first pattern-6dB bandwidth is 770-885MHz, 1520-1660MHz and 2260-2560MHz, covers GSM850, GPS and bluetooth frequency range; Said second pattern-6dB bandwidth is 875-1010MHz and 1705-2410MHz, covers GSM900, DCS and PCS frequency range.Antenna efficiency test result with Fig. 3, sized shown in Figure 4 is as shown in Figure 6, is higher than 53.6% for GSM frequency range efficient, is higher than 26.4% for GPS, DCS, PCS and UMTS frequency range efficient, is higher than 46.4% for bluetooth frequency range efficient.Said antenna system can be at 60 * 5 * 5mm
3The space in realize the covering of 7 frequency ranges.