CN102576936A - Methods for reducing near-field radiation and specific absorption rate (SAR) values in communications devices - Google Patents

Abstract

A method is provided for reducing near-field radiation and specific absorption rate (SAR) values in a communications device. The communications device includes a multimode antenna structure transmitting and receiving electromagnetic signals and circuitry for processing signals communicated to and from the antenna structure. The antenna structure includes: a plurality of antenna ports operatively coupled to the circuitry; a plurality of antenna elements, each operatively coupled to a different one of the antenna ports; and one or more connecting elements electrically connecting the antenna elements at a location on each antenna element that is spaced apart from an antenna port coupled thereto to form a single radiating structure and such that electrical currents on one antenna element flow to a connected neighboring antenna element and generally bypass the antenna port coupled to the neighboring antenna element, the electrical currents flowing through the one antenna element and the neighboring antenna element being generally equal in magnitude,; such that an antenna mode excited by one antenna port is generally electrically isolated from a mode excited by another antenna port at a given desired signal frequency range and the antenna structure generates diverse antenna patterns. The method includes adjusting the relative phase between signals fed to neighboring antenna ports of the antenna structure such that a signal fed to the one antenna port has a different phase than a signal fed to the neighboring antenna port to provide antenna pattern control and to increase gain in a selected direction toward a receive point.; The method features using a transmit power lower than the transmit power used in a non-pattern control operation of the antenna structure such that the communications device obtains generally equivalent wireless link performance with the receive point using reduced transmit power compared to the non- pattern control operation, thereby reducing the specific absorption rate.

Description

Be used for reducing the near-field thermal radiation of communication equipment and the method for special absorption ratio (SAR) value

The cross reference of related application

The application is the Patent Application No. of submitting on March 30th, 2,010 12/750 that is entitled as " Multimode Antenna Structure (multi-mode antenna structure) "; 196 part continuation application; And this application is the Patent Application No. of submitting on April 8th, 2,008 12/099 that is entitled as " Multimode Antenna Structure (multi-mode antenna structure) "; 320 (are U.S. Patent number 7 by bulletin; 688,273) continuation application, and this application is the Patent Application No. of submitting on June 27th, 2,007 11/769 that is entitled as " Multimode Antenna Structure (multi-mode antenna structure) "; 565 (are U.S. Patent number 7 by bulletin; 688,275) part continuation application, this application are based on the U.S. Provisional Patent Application that is entitled as " Multimode Antenna Structure (multi-mode antenna structure) " submitted on April 20th, 2007 number 60/925; 394 and also be the U.S. Provisional Patent Application number 60/916,655 of " Multimode Antenna Structure (multi-mode antenna structure) " at the title that on May 8th, 2007 submitted to.The application still is the U.S. Provisional Patent Application number 61/181,176 of " Multimode Antenna Structure (multi-mode antenna structure) " based on the title of submitting on May 26th, 2009.Each application in the application of above-identified is incorporated this paper into through quoting.

Background technology

The present invention relates generally to Wireless Telecom Equipment, relates in particular to be used for reducing the near-field thermal radiation of these equipment and the method for special absorption ratio (SAR) value.

Many communication equipments have a plurality of being close together (for example, at a distance of less than wavelength 1/4) encapsulation and antennas operating in same frequency band simultaneously.The common example of these communication equipments comprises the portable communications product, such as cellular handset, PDA(Personal Digital Assistant) and wireless networking device or be used for the data card of personal computer (PC).Many system architectures (such as multiple-input, multiple-output (MIMO)) and the standard agreement (such as 802.11n that is used for WLAN and 3G data communication, such as 802.16e (WiMAX), HSDPA and 1xEVDO) that is used for mobile radio communication apparatus need a plurality of antennas to work simultaneously.

Summary of the invention

According to one or more embodiment, a kind of be used for the reducing near-field thermal radiation of communication equipment and the method for special absorption ratio (SAR) value are provided.The circuit that this communication equipment comprises the multi-mode antenna structure of transmission and receiving electromagnetic signals and is used to handle the signal of being to and from the antenna structure transmission.This antenna structure comprises: a plurality of antenna ports that operationally are coupled to said circuit; A plurality of antenna elements, each antenna element operationally are coupled to the different antennas port in the said antenna port; And one or more Connection Elements; These one or more Connection Elements with the antenna port that is coupled to it isolated each antenna element on the position be electrically connected said antenna element; To form single irradiation structure and to make adjacent antenna elements that current direction on the antenna element connects and walk around the antenna port that is coupled in said adjacent antenna elements substantially; The electric current that flows through a said antenna element and said adjacent antenna elements equates on amplitude substantially; So that at given desired signal frequency range place by the antenna mode of antenna port excitation with by pattern that another antenna port encouraged electrical isolation basically, and said antenna structure generates the different antennas directional diagram.This method comprise adjustment be fed to the relative phase between the signal of adjacent antenna port of said antenna structure so that be fed to the signal of a said antenna port have with the signal different phase that is fed to said adjacent antenna port antenna pattern control to be provided and to increase the gain on the preferential direction of acceptance point.This method feature is to use the transmitted power that is lower than the transmitted power of in non-directional diagram (non-pattern) control operation of antenna structure, using so that the radio link performance that the acquisition of said communication equipment is equal to substantially; Wherein said acceptance point uses and compares the transmitted power that reduces with said non-directional diagram control operation, reduces said special absorption ratio thus.

According to one or more further embodiment, a kind of be used for the reducing near-field thermal radiation of communication equipment and the method for special absorption ratio (SAR) value are provided.The circuit that this communication equipment comprises the aerial array of transmission and receiving electromagnetic signals and is used to handle the signal of being to and from said aerial array transmission.This aerial array comprises a plurality of radiant elements, and each radiant element has the antenna port that operationally is coupled to this circuit.This method comprise adjustment be fed to the relative phase between the signal of said antenna port of said aerial array so that be fed to the signal of an antenna port have with the signal different phase that is fed to another antenna port antenna pattern control to be provided and to increase the gain on the preferential direction of acceptance point.This method feature is to use the transmitted power that is lower than the transmitted power of in the non-directional diagram control operation of aerial array, using so that the radio link performance that the acquisition of said communication equipment is equal to substantially; Wherein said acceptance point uses and compares the transmitted power that reduces with said non-directional diagram control operation, reduces said special absorption ratio thus.

Description of drawings

Figure 1A shows the antenna structure with two parallel dipole antennas (dipole).

Figure 1B shows an electric current that dipole antenna produced in the antenna structure that encourages Figure 1A.

Fig. 1 C shows and the corresponding model of the antenna structure of Figure 1A.

Fig. 1 D is the figure of scattering parameter that the antenna structure of Fig. 1 C is shown.

Fig. 1 E is the figure of current ratio that the antenna structure of Fig. 1 C is shown.

Fig. 1 F is the figure of gain pattern (gain pattern) that the antenna structure of Fig. 1 C is shown.

Fig. 1 G is the figure of envelope correlation that the antenna structure of Fig. 1 C is shown.

Fig. 2 A shows the antenna structure with two parallel dipole antennas that connected by Connection Element according to one or more embodiment of the present invention.

Fig. 2 B shows and the corresponding model of the antenna structure of Fig. 2 A.

Fig. 2 C is the figure of scattering parameter that the antenna structure of Fig. 2 B is shown.

Fig. 2 D is the figure of scattering parameter that the antenna structure of Fig. 2 B is shown, and wherein has the impedance matching of lamped element two ports.

Fig. 2 E is the figure of current ratio that the antenna structure of Fig. 2 B is shown.

Fig. 2 F is the figure of gain pattern that the antenna structure of Fig. 2 B is shown.

Fig. 2 G is the figure of envelope correlation that the antenna structure of Fig. 2 B is shown.

Fig. 3 A shows the antenna structure with two parallel dipole antennas that connected by circuitous Connection Element according to one or more embodiment of the present invention.

Fig. 3 B is the figure of scattering parameter that the antenna structure of Fig. 3 A is shown.

Fig. 3 C is the figure of current ratio that the antenna structure of Fig. 3 A is shown.

Fig. 3 D is the figure of gain pattern that the antenna structure of Fig. 3 A is shown.

Fig. 3 E is the figure of envelope correlation that the antenna structure of Fig. 3 A is shown.

Fig. 4 shows the antenna structure with ground connection or balancer (counterpoise) according to one or more embodiment of the present invention.

Fig. 5 shows the balanced type antenna structure according to one or more embodiment of the present invention.

Fig. 6 A shows the antenna structure according to one or more embodiment of the present invention.

Fig. 6 B is the figure that illustrates for the scattering parameter of the antenna structure of Fig. 6 A of specific dipole antenna width dimensions.

Fig. 6 C is the figure that illustrates for the scattering parameter of the antenna structure of Fig. 6 A of another dipole antenna width dimensions.

Fig. 7 shows the antenna structure on the printed circuit board (PCB) that is manufactured on according to one or more embodiment of the present invention.

Fig. 8 A shows the antenna structure with double resonance according to one or more embodiment of the present invention.

Fig. 8 B is the figure of scattering parameter that the antenna structure of Fig. 8 A is shown.

Fig. 9 shows the tunable antenna structure according to one or more embodiment of the present invention.

Figure 10 A and Figure 10 B show according to having of one or more embodiment of the present invention and are positioned at along the antenna structure of the Connection Element at the diverse location place of the length of this antenna element.

Figure 10 C and Figure 10 D are respectively the figure of scattering parameter that the antenna structure of Figure 10 A and Figure 10 B is shown.

Figure 11 shows the antenna structure that has the Connection Element of switch according to comprising of one or more embodiment of the present invention.

Figure 12 shows according to the antenna structure that has comprising of one or more embodiment of the present invention with the Connection Element of the filter of its coupling.

Figure 13 shows according to the antenna structure that has comprising of one or more embodiment of the present invention with two Connection Elements of the filter of its coupling.

Figure 14 shows the antenna structure with tunable Connection Element according to one or more embodiment of the present invention.

Figure 15 shows the antenna structure on the PCB assembly that is installed in according to one or more embodiment of the present invention.

Figure 16 shows another antenna structure on the PCB assembly that is installed in according to one or more embodiment of the present invention.

Figure 17 shows according to the alternate antenna structure on the be installed in PCB assembly of one or more embodiment of the present invention.

Figure 18 A shows the three-mode antenna structure according to one or more embodiment of the present invention.

Figure 18 B is the figure of gain pattern that the antenna structure of Figure 18 A is shown.

Figure 19 shows according to the antenna that is used for antenna structure of one or more embodiment of the present invention and power amplifier combiner and uses.

Figure 20 A and Figure 20 B show the multi-mode antenna structure that can in for example WiMAX USB or ExpressCard/34 equipment, use according to one or more further embodiment of the present invention.

Figure 20 C shows the test suite of the performance of the antenna that is used for survey map 20A and Figure 20 B.

Figure 20 D shows the thermometrically result of the antenna of Figure 20 A and Figure 20 B to Figure 20 J.

Figure 21 A and Figure 21 B show the multi-mode antenna structure that can in WiMAX USB softdog (dongle) for example, use according to one or more alternative embodiments of the present invention.

Figure 22 A and Figure 22 B show the multi-mode antenna structure that can in WiMAX USB softdog for example, use according to one or more alternative embodiments of the present invention.

Figure 23 A shows the test suite of the performance of the antenna that is used for survey map 21A and Figure 21 B.

Figure 23 B shows the thermometrically result of the antenna of Figure 21 A and Figure 21 B to Figure 23 K.

Figure 24 is the schematic block diagram according to the antenna structure with beam steering (beam steering) mechanism of one or more embodiment of the present invention.

Figure 25 A shows the thermometrically result of the antenna of Figure 25 A to 25G.

Figure 26 shows the gain advantage of the antenna structure that one or more embodiment according to the present invention become with the phase angle difference between the distributing point.

Figure 27 A is the sketch map that simple double frequency-band branch line monopole antenna structure is shown.

Figure 27 B shows the CURRENT DISTRIBUTION in the antenna structure of Figure 27 A.

Figure 27 C is the sketch map that the branch line band stop filter is shown.

Figure 27 D and Figure 27 E illustrate the test result that the frequency of the antenna structure of Figure 27 A suppresses.

Figure 28 is the sketch map that illustrates according to the antenna structure with frequency band restrain tank of one or more embodiment of the present invention.

Figure 29 A illustrates the alternate antenna structure with frequency band restrain tank according to one or more embodiment of the present invention.

Figure 29 B and Figure 29 C show the thermometrically result of the antenna structure of Figure 29 A.

Figure 30 shows the exemplary USB softdog with two-port antenna structure of the directional diagram control application that is used for the 1900MHz frequency band.

Figure 31 illustrates the SAR value of confirming through the equipment of simulation Figure 30.

Embodiment

According to various embodiments of the present invention, the multi-mode antenna structure that is used in the communication equipment to send with receiving electromagnetic signals is provided.These communication equipments comprise being used to handle and are delivered to and from the circuit of the signal of antenna structure.This antenna structure comprises a plurality of antenna ports that operationally are coupled to this circuit, and a plurality of antenna element, and each antenna element operationally is coupled to the different antennas port.This antenna structure also comprise one or more Connection Elements of being electrically connected these antenna element so that at given signal frequency range place by the antenna mode of an antenna port excitation with by the pattern of another antenna port excitation electrical isolation basically.In addition, the antenna pattern created of these antenna demonstrates and has low relevant well-defined directional diagram diversity (pattern diversity).

Antenna structure according to various embodiments of the present invention is close together a plurality of antennas (for example at needs; At a distance of less than 1/4 wavelength) in the communication equipment of encapsulation; Be included in and particularly in same frequency band, use simultaneously above in the equipment of an antenna, particularly useful.Can use the common example of these equipment of this antenna structure to comprise the portable communications product, such as cellular handset, PDA and wireless networking device or be used for the data card of PC.This antenna structure also with a plurality of antennas of needs operate simultaneously particularly useful when using such as the system architecture of MIMO and the standard agreement that is used for mobile radio communication apparatus (such as the 802.11n that is used for WLAN and such as the 3G data communication of 802.16e (WiMAX), HSDPA and 1xEVDO).

Figure 1A-1G shows the operation of antenna structure 100.Figure 1A schematically shows the antenna structure 100 of the parallel antenna that to have two length be L, specifically is parallel dipole antenna 102,104.Dipole antenna 102,104 apart d, and do not couple together through any Connection Element.Dipole antenna 102,104 has the fundamental resonant frequency that equates with L=λ/2 substantially.Each dipole antenna is connected in independently transmission/receiving system, and this system can operate at the same frequency place.For two antennas, this system connects can have identical characteristic impedance z0, and this characteristic impedance in this example is 50 ohm.

When a dipole antenna is just sending signal, the part of the signal that this dipole antenna was sending will be directly coupled to adjacent dipole antenna.The maximum of coupling appears near the half wave resonances frequency of this single dipole antenna usually, and when apart d diminishes, increases.For example, for d＜λ/3, the amplitude of coupling greater than 0.1 or-10dB, for d＜λ/8, the amplitude of coupling is greater than-5dB.

Not coupling (that is, isolating fully) or the coupling that reduces between antenna are desired between antenna.If coupling be for example-10dB, then 10 of transmitted power lost because the power of so big amount are directly coupled in the adjacent antenna.Also possibly there is negative systematic influence, reduces, perhaps be connected to the reduction of performance of the transmitter of adjacent antenna such as the saturated or sensitivity of the receiver that is connected to adjacent antenna.The gain pattern that the electric current of on adjacent antenna, responding to is generated gain pattern and single dipole antenna is compared the generation distortion.Know that this influence has reduced being correlated with between the gain pattern that dipole antenna generated.Therefore, although coupling can provide certain directional diagram diversity, yet it has negative systematic influence recited above.

Because near coupling,, and can be considered to have the antenna system with two corresponding two pairs of terminals of different gain pattern or port so antenna does not work alone.Use any a pair of port to relate to total basically, comprise two dipole antennas.The parasitic excitation of adjacent dipole antenna make it possible to near dipole realize branch collection at interval, yet the electric current that on this dipole antenna, encourages flows through source impedance, and therefore shows intercoupling between port.

It is right that Fig. 1 C shows antenna structure 100 corresponding model dipole antennas that be used to simulate and shown in Fig. 1.In this example, dipole antenna 102,104 has the square-section of 1mm x 1mm and the length (L) of 56mm.When the source that attaches to 50 ohm, these sizes produce the central resonance frequency of 2.45GHz.The free space wavelength at this frequency place is 122mm.The scattering parameter S11 of the apart (d) (or about λ/12) for 10mm and the figure of S12 have been shown among Fig. 1 D.Since symmetry and reciprocity, S22=S11 and S12=S21.For the sake of simplicity, only illustrate and discuss S11 and S12.In this configuration, the coupling between the dipole antenna of being represented by S12 reaches-maximum of 3.7dB.

Fig. 1 E show that port one 06 is energized and port one 08 by the ratio (being identified as " amplitude I2/I1 " in the drawings) of the vertical current on the vertical current on the dipole antenna 104 of this antenna structure under the situation of no seedbed termination and the dipole antenna 102.This current ratio (dipole antenna 104/ dipole antenna 102) be the frequency at maximum place corresponding to 180 between this dipole antenna electric current degree phase differential frequency, and on frequency only a little more than the maximum Coupling point shown in Fig. 1 D.

Fig. 1 F shows azimuth (azimuthal) gain pattern of some frequencies under the situation that port one 06 is energized.These directional diagrams are not omnidirectional equably, but because the change of amplitude and the phase place of coupling and along with frequency shift.Because symmetry, the directional diagram that draws from the excitation of port one 08 should be the mirror image of the directional diagram of port one 06.Therefore, this directional diagram is from left to right asymmetric more, and these directional diagrams are more different aspect gain range.

The calculating of the relative coefficient between directional diagram provides directional diagram multifarious quantization characteristic.Fig. 1 G show between the antenna pattern of port one 06 and port one 08 calculated relevant.It is much lower that the clarke model of the dipole antenna that this correlation ratio is desirable is predicted.This is because the difference of the directional diagram introduced of intercoupling.

Fig. 2 A-2F shows the operation according to the exemplary two-port antenna structure 200 of one or more embodiment of the present invention.Two-port antenna structure 200 comprises two closely isolated resoant antenna elements 202,204 and not only low directional diagram correlation (pattern correlation) is provided but also the low coupling of 206,208 of ports.Fig. 2 A schematically shows two-port antenna structure 200.This similar is in the antenna structure that comprises this electrode couple antenna 100 shown in Figure 1B, but also is included in the level conduction Connection Element 210,212 between the dipole antenna of any side of port 206,208.The antenna structure of two ports 206,208 and Fig. 1 is positioned at same position.When a port is energized, combining structure demonstrate with non-attached dipole antenna to similar resonance, the directional diagram diversity increases but coupling obviously reduces.

Exemplary model with 10mm dipole antenna antenna structure 200 at interval has been shown among Fig. 2 B.This structure and the antenna structure 100 shown in Fig. 1 C have identical substantially geometry, but added be electrically connected a little more than with two horizontal Connection Elements 210,212 a little less than the antenna element of port.This structure demonstrate with the strong resonance at non-attached dipole antenna same frequency place, but have the very different scattering parameter shown in Fig. 2 C.Exist coupling very big reduction (be lower than-20dB) and by the skew of the input impedance of S11 indication.In this example, optimum impedance coupling (S11 minimum value) is not consistent with minimum coupling (S12 minimum value).Matching network can be used for improving input impedance matching, still realizes low-down coupling simultaneously, shown in Fig. 2 D.In this example, comprise that series reactor is that the lamped element matching network of by-pass capacitor is added between each port and this structure at the back.

Fig. 2 E shows the ratio (being indicated as " amplitude I2/I1 " in the drawings) of the electric current on dipole aerial element 204 that the excitation by port 206 obtains and the dipole aerial element 202.This illustrates under resonance frequency, and electric current is in fact bigger on dipole aerial element 204.At near-resonance, along with the increase of frequency, the electric current on the dipole aerial element 204 begins to reduce with respect to the electric current on the dipole aerial element 202.Minimum Coupling point (being 2.44GHz in this example) appears at electric current on these two dipole aerial elements near the frequency that equates substantially on the amplitude.At this frequency place, the phase place of the electric current on the dipole aerial element 204 is than about 160 degree of the phase lag of the electric current of dipole antenna element 202.

Different with the dipole antenna that does not have Connection Element of Fig. 1 C, the electric current on the antenna element 204 of the combined antenna structure 200 of Fig. 2 B is not forced to the terminal impedance of passing port 208.On the contrary, be downward through antenna element 204 at electric current, cross over Connection Element 210 and 212, produce resonance mode when also upwards flowing through antenna element 202, indicated like the arrow that illustrates on Fig. 2 A.(notice that this electric current is represented the half the of circulation that resonate; During second half, current opposite in direction).The characteristic of the resonance mode of combining structure is following: the electric current major part on (1) antenna element 204 is walked around port 208; Thereby for the high degree of isolation between the port 206 and 208 creates conditions; And the amplitude of the electric current on (2) two antenna elements 202,204 about equally; This creates conditions for not similar and incoherent gain pattern, as that kind that is described in more detail below.

Because the amplitude of electric current be close to equate,, produce the directional diagram of multidirectional (shown in Fig. 2 F) more so compare with situation than the antenna structure of the non-attached dipole antenna of having among Fig. 1 C on antenna element.When electric current equated, the condition that on x direction (or φ=0), directional diagram is made zero was the phase place of the electric current on the dipole antenna 204 than the amount of the phase lag π-kd of the electric current on the dipole antenna 202 (wherein k=2 π/λ, and λ is an EWL).With this understanding, will spend with the field out-phase of propagating from dipole antenna 202 180 from the field that dipole antenna 204 is propagated on φ=0 direction, so this combination of two will have null value on the direction of φ=0.

In the model example of Fig. 2 B, d is 10mm or λ/12 effective electrical lengths.Therefore in the case, kd equals π/6 or 30 degree, and is to 150 degree after the current hysteresis on the current ratio dipole antenna 202 on the dipole antenna 204 towards the null value of φ=0 with towards the condition of the directivity azimuth antenna pattern of the maximum gain of φ=180.In resonance place, electric current flows through (shown in Fig. 2 E) near this condition, and this has explained the directivity of directional diagram.Under the situation of excitation dipole antenna 204, antenna pattern is the mirror-inverted of the antenna pattern of Fig. 2 F, and maximum gain is on the direction of φ=0.Difference by between the antenna pattern of two ports generations has the low prediction envelope correlation that is associated shown in Fig. 2 G.Therefore, the combined antenna structure has two ports that are isolated from each other and produces low relevant gain pattern.

Correspondingly, the characteristic of Connection Element 210,212 is depended in the frequency response of coupling, comprises their impedance and electrical length.According to one or more embodiment of the present invention, can keep above that expecting that the frequency of isolation amount or bandwidth control through suitable configuration Connection Element.It is a kind of that to dispose cross-coupled mode be the physical length that changes Connection Element.The example of this point has wherein increased circuitous shown in the multi-mode antenna structure 300 of Fig. 3 A to the interconnection path of Connection Element 310,312.This has brought the electrical length that increases by two antenna elements 302, the connection between 304 and the roughly influence of impedance.Fig. 3 B, 3C, 3D and 3E show the performance characteristic of this structure respectively, comprise scattering parameter, current ratio, gain pattern and directional diagram correlation.In the present embodiment, the variation of physical length does not also have significantly to change the resonance frequency of this structure, but there is marked change in S12, compares with the structure that does not have to make a circulation to have bigger bandwidth and bigger minimum value.Therefore, it is possible optimizing or improve isolation performance through the electric characteristic that changes Connection Element.

Exemplary multi-mode antenna structure according to various embodiments of the present invention can be designed to from ground or balancer 402 excitations (shown in the antenna structure 400 of Fig. 4), perhaps as balanced structure (shown in the antenna structure of Fig. 5).In either case, each antenna structure comprise two or more antenna elements (402 among Fig. 4,404 and Fig. 5 in 502,504) and one or more conduction Connection Element (506,508 among 406 among Fig. 4 and Fig. 5).In order to describe, only show the two-port structure in the exemplary plot.Yet, according to various embodiments of the present invention, be to comprise that more than two ports be possible with this structural extended.Be provided at each antenna element place antenna structure or port (Fig. 4 418,412 with Fig. 5 510,512) signal be connected.This Connection Element provides being electrically connected between two antenna elements in frequency place that is paid close attention to or frequency range.Although this antenna physically with electric on be a structure, yet can through it is used as two independently antenna explain its operation.For the antenna structure that does not comprise Connection Element (such as antenna structure 100), the port one 06 of this structure can be called as and is connected to antenna 102, and port one 08 can be called as and is connected to antenna 104.Yet in the situation of this combining structure (such as antenna structure 400), port 418 can be called as with an antenna mode and is associated, and port 412 can be called as with another antenna mode and is associated.

These antenna element is designed in the operating frequency place of expectation or operating frequency range, resonate.Lowest-order resonance occurs when antenna element has quarter-wave electrical length.Therefore, in the situation of non-equilibrium configuration, a kind of simple elements design is the unipole antenna of quarter-wave.Using more, the pattern of high-order also is possible.For example, the structure that is formed by the quarter-wave unipole antenna also demonstrates double mode antenna performance, has high the isolation at the frequency place of three times of fundamental frequencies.Therefore, can utilize more higher order mode to create multiband antenna.Similarly, in balanced arrangement, these antenna element can be like the complementary quarter-wave elongate elements in half-wave center-fed (center-fed) dipole antenna.Yet this antenna structure can also be made up of the antenna element of the other types that in expected frequency place or frequency range, resonate.Other possible antenna element configuration include but not limited to that helical coil, broadband flat shape, antenna component, circuitous shape, ring and inductance type bypass form are such as planar inverted-F antenna (PIFA).

According to the antenna element of the antenna structure of one or more embodiment of the present invention not needs have the identical geometry or the antenna element of same type.These antenna element should each all have in the operating frequency place of expectation or the resonance in the operating frequency range.

According to one or more embodiment of the present invention, the antenna element of antenna structure has identical geometry.Normally simplicity of design property is desired for this, when ought be identical as far as the connection antenna performance requirement of arbitrary port particularly.

The bandwidth of combined antenna structure and resonance frequency can be by the bandwidth and the resonance frequency controls of these antenna element.Therefore, for as in the pattern of the combining structure shown in Fig. 6 A, 6B and the 6C, wideer bandwidth element can be used for producing wideer bandwidth.Fig. 6 A shows the multi-mode antenna structure 600 that comprises two dipole antennas 602,604 that connected by Connection Element 606,608.Dipole antenna 602,604 has wide (W) and long (L) separately and is spaced apart out distance (d).Fig. 6 B shows the scattering parameter of the structure with following exemplary size: W=1mm, L=57.2mm, and d=10mm.Fig. 6 C shows the scattering parameter of the structure with following exemplary size: W=10mm, L=50.4mm, and d=10mm.As shown in, W is increased to 10mm from 1mm, keep other general size identical simultaneously, bring the wideer isolation bandwidth and the impedance bandwidth of this antenna structure.

Find that also the interval between the increase antenna element has increased the isolation bandwidth and the impedance bandwidth of antenna structure.

Generally speaking, Connection Element is in the high galvanic areas of this combination resonance structure.Therefore, to have high conductivity be preferred to Connection Element.

These ports are positioned at the distributing point place of this antenna element, like them during as the antenna operation that separates.Matching element or structure can be used for port Impedance is matched the system impedance of expectation.

According to one or more embodiment of the present invention, this multi-mode antenna structure can be the planar structure that is incorporated in the printed circuit board (PCB) for example, and is as shown in Figure 7.In this example, antenna structure 700 is included in the antenna element 702,704 that port 708,710 places are coupled together by Connection Element 706.This antenna structure is fabricated on the printed circuit board base board 712.Antenna element shown in the figure is simple quarter-wave unipole antenna.Yet these antenna element can be any geometry that produces equivalent effective electrical length.

Therefore according to one or more embodiment of the present invention, the antenna element with double resonance frequency can be used for producing and has the double resonance frequency and have the combined antenna structure of duplexing working frequency.Fig. 8 A shows the example model of multi-mode dipole antenna configuration 800, and wherein dipole aerial element 802,804 is divided into two finger pieces that are uneven in length 806,808 and 810,812 respectively.Dipole aerial element has the resonance frequency that each all different with two finger piece length is associated and correspondingly demonstrates double resonance.Similarly, use the multi-mode antenna structure of double resonance dipole antenna arm to demonstrate two frequency bands, wherein obtained high isolation (or littler S21), shown in Fig. 8 B.

According to one or more embodiment of the present invention, the multi-mode antenna structure 900 shown in Fig. 9 is provided, this structure has the variable-length antenna element 902,904 that forms tunable antenna.Realize this point through using the effective electrical length that changes these antenna element such as may command device at the RF switch 906,908 at each antenna element 902,904 place.In this example, this switch can be opened (through operation may command device) create shorter electrical path (to be used for the operation of higher frequency) or be closed to create longer electrical path (to be used for more low-frequency operation).The working band that comprises the antenna structure 900 of high characteristic of isolating can come tuning through collaborative tuning these two antenna elements.The method can be used with the method for the effective electrical length of multiple change antenna element; The method of this effective electrical length comprises; For example; Use the may command dielectric material, use variable capacitor to load this antenna element, and be switched on or switched off parasitic antenna such as MEM device, variable reactor or tunable dielectric capacitor.

According to one or more embodiment of the present invention, these one or more Connection Elements are providing electrical length to be substantially equal to being electrically connected of electrical distance between the element between the antenna element.With this understanding, and when Connection Element is attached at the port end place of antenna element, near the frequency place isolation of the port resonance frequency of antenna element.This layout can produce at the CF place to be close to perfectly isolates.

Alternatively, as previous discussion, the electrical length of this Connection Element can be increased with expansion isolates the bandwidth that exceeds particular value above that.For example, the direct connection between the antenna element can be at the CF place the minimum S21 of generation-25dB, and S21＜-bandwidth of 10dB can be 100MHz.Through increasing this electrical length, can obtain new response, but wherein minimum S21 be added to-15dB S21＜-bandwidth of 10dB can be added to 150MHz.

Various other multi-mode antenna structures according to one or more embodiment of the present invention are possible.For example, Connection Element can have the geometry of variation or can be constructed to comprise the parts of the attribute that changes this antenna structure.These parts can comprise, for example passive inductors and capacitor element, resonator or filter construction or such as the active parts of phase shifter.

According to one or more embodiment of the present invention, this Connection Element can be changed to adjust the attribute of this antenna structure along the position of the length of this antenna element.Far-end towards antenna element moves away from port through the attachment point with the Connection Element on the antenna element, can be with the upwards skew on frequency of the segregate above that frequency band of port.Figure 10 A and 10B show multi-mode antenna structure 1000,1002 respectively, and each antenna structure has the Connection Element that is connected electrically to antenna element.In the antenna structure 1000 of Figure 10 A, Connection Element 1004 in this structure so that the gap between the top of Connection Element 1004 and ground plane 1006 is 3mm.Figure 10 C shows the scattering parameter of such structure, and this structure is illustrated in this configuration and obtains high the isolation at the frequency place of 1.15GHz.Shunt capacitance/series inductance matching network is used to provide the impedance matching at 1.15GHz place.Figure 10 D shows the scattering parameter of the structure 1002 of Figure 10 B, and wherein the gap between the top 1010 of Connection Element 1008 and ground plane is 19mm.The antenna structure 1002 of Figure 10 B demonstrates the working band that has high isolation at about 1.50GHz place.

Figure 11 schematically shows the multi-mode antenna structure 1100 according to one or more further embodiment of the present invention.Antenna structure 1100 comprises two or more Connection Elements 1102,1104, and each Connection Element is electrically connected antenna element 1106,1108.(, only show two Connection Elements among the figure in order to describe.Should be appreciated that also to have conceived to use and surpass two Connection Elements.) Connection Element 1102,1104 is spaced apart from each other along antenna element 1106,1108.In the Connection Element 1102,1104 each comprises switch 1112,1110.Can select the peak value isolation frequency through control switch 1110,1112.For example, can and open switch 1112 and select frequency f 1 through off switch 1110.Can and open switch 1110 and select different frequency f 2 through off switch 1112.

Figure 12 shows the multi-mode antenna structure 1200 according to one or more alternate embodiments of the present invention.Antenna structure 1200 comprises the Connection Element 1202 that has operationally with the filter 1204 of its coupling.Filter 1204 can be the low pass so selected or band pass filter, and only in desired frequency band, (to isolate resonance frequency such as height) be effective so that antenna element 1206, the Connection Element between 1208 connect.At the upper frequency place, this structure will look like not conducted electricity the antenna element of two separation of Connection Element (it is opened a way) coupling and operate.

Figure 13 shows the multi-mode antenna structure 1300 according to one or more alternate embodiments of the present invention.Antenna structure 1300 comprises two or more Connection Elements 1302,1304, and they comprise filter 1306,1308 respectively.(, only show two Connection Elements among the figure in order to describe.Should be appreciated that also to have conceived to use and surpass two Connection Elements.) in a kind of possible embodiment; Antenna structure 1300 has low pass filter 1308 and on Connection Element 1302, has high pass filter 1306 has the frequency band of two high isolation with establishment antenna structure on Connection Element 1304 (it is more near antenna port); That is double frequency-band structure.

Figure 14 shows the multi-mode antenna structure 1400 according to one or more alternate embodiments of the present invention.Antenna structure 1400 comprises the one or more Connection Elements 1402 with operationally connected tuned element 1406.Antenna structure 1400 also comprises antenna element 1408,1410.The electric resistance impedance that delay that tuned element 1406 changes are electrically connected or phase place or change are electrically connected.The amplitude of scattering parameter S21/S12 and frequency response receive electrical delay or impedance variation influence and therefore use tuned element 1406 to transform or optimize antenna structure prevailingly to the isolation at CF place.

Figure 15 shows the multi-mode antenna structure 1500 according to one or more alternate embodiments of the present invention.Multi-mode antenna structure 1500 can for example use in WIMAX USB softdog.Antenna structure 1500 can be configured to for example from 2300 to 2700MHz WiMAX frequency band, working.

Antenna structure 1500 comprises two antenna elements 1502,1504 that connected by conduction Connection Element 1506.These antenna element comprises electrical length the operating frequency range to obtain expect of groove to increase element.In this example, antenna structure is optimized for the centre frequency of 2350MHz.The length of these grooves can be reduced to obtain higher centre frequency.This antenna structure is installed on the printed circuit-board assembly 1508.The element coupling of lump two parts is provided at each antenna feed place.

Antenna structure 1500 can for example be made through metal stamping.For example, it can be made by the thick alcu alloy film of 0.2mm.Antenna structure 1500 is included in and picks up characteristic 1510 on the Connection Element of center of main body of this structure, and this characteristic can be picked up automatically-reached-placing in the assembling process and use.This antenna structure also refluxes with mounted on surface and assembles compatibility.

Figure 16 shows the multi-mode antenna structure 1600 according to one or more alternate embodiments of the present invention.As the antenna structure 1500 of Figure 15, antenna structure 1600 also can for example use in WIMAX USB softdog.This antenna structure can be configured to for example from 2300 to 2700MHz WiMAX frequency band, working.

Antenna structure 1600 comprises two antenna elements 1602,1604, and each antenna element comprises circuitous unipole antenna.Circuitous length has been confirmed centre frequency.Exemplary design shown in the figure is optimized for the centre frequency of 2350MHz.In order to obtain higher centre frequency, the length that can reduce to make a circulation.

Connection Element 1606 is electrically connected antenna element.The element coupling of lump two parts is provided at each antenna feed place.

This antenna structure can be for example by flexible, as the flexible print circuit (FPC) that is installed on the plastic carrier 1608.This antenna structure can be assigned to create by the metallization of this FPC.This plastic carrier provides mechanical support and is convenient to be installed on the PCB assembly 1610.Alternatively, this antenna structure can be formed by sheet metal.

Figure 17 shows multi-mode antenna structure 1700 according to another embodiment of the present invention.This Antenna Design can for example be used for USB, Express 34 and Express 54 data card forms.Exemplary antenna arrangements shown in the figure is designed to work in the frequency from 2.3 to 6GHz.This antenna structure for example can be made by the sheet metal manufacturing or through the FPC on plastic carrier 702.

Figure 18 A shows multi-mode antenna structure 1800 according to another embodiment of the present invention.Antenna structure 1800 comprises the three-mode antenna with three ports.In this structure, use Connection Element 1808 that three monopole antenna elements 1802,1804,1806 are coupled together, Connection Element 1808 comprises the conducting ring that connects adjacent antenna elements.These antenna element comes balance by shared balancer or sleeve pipe 1810, and sleeve pipe 1810 is conductive poles of single hollow.This antenna has three coaxial cables 1812,1814,1816, is used for this antenna structure is connected to communication equipment.The hollow that coaxial cable 1812,1814,1816 passes sleeve pipe 1810.This antenna module can be by the single flexible printed circuit configurations that is rolled into cylinder, and can be encapsulated in the plastic housing of cylindricality so that the individual antenna assembly in the place that takies three antennas that separate to be provided.In an exemplary arrangement, the diameter of cylinder is 10mm and the total length of antenna is 56mm so that be between port with height isolation work at 2.45GHz.This antenna structure can use with a plurality of antenna wireless electric systems (such as MIMO that in 2.4 to 2.5GHz frequency bands, works or 802.11N system).Except port-to-port was isolated, each port advantageously produced the different gain pattern shown in Figure 18 B.Although this is a concrete example, yet should be appreciated that this structure can be by convergent-divergent to operate at any expected frequency place.It is also understood that tuning, as to control bandwidth and the establishment multiband structure method of before in the background of two-port antenna, describing that is used for also can be applicable to this multiport structure.

Although the foregoing description is shown as real cylinder, also be possible yet use three antenna elements producing same advantage and other layouts of Connection Element.This includes but not limited to have direct connection so that each Connection Element forms the layout of triangle or another polygon geometry.Through constructing similar structure with shared balancer three dipole aerial elements that separate of connection rather than three monopole antenna elements similarly also is possible.And; Although the symmetric arrangement of antenna element advantageously produces identical performance for each port; For example, identical bandwidth, isolation, impedance matching, however depend on and use and asymmetric ground or arrange that with unequal interval antenna element also is possible.

Figure 19 shows the use of multi-mode antenna structure 1900 in combiner is used according to one or more embodiment of the present invention.Shown in figure, send two antenna ports that signal can be applied to antenna structure 1900 simultaneously.In this configuration, this multi-mode antenna can serve as antenna and power amplifier combiner.Height between antenna port is isolated and has been limited two amplifiers 1902, mutual between 1904, has known that this has the influence of not expecting, such as distorted signals and loss in efficiency.Can be provided at the optional impedance matching at 1906 places at the antenna port place.

Figure 20 A and 20B show the multi-mode antenna structure 2000 according to one or more alternate embodiments of the present invention.Antenna structure 200 also can use in WiMAX USB or ExpressCard/34 device.This antenna structure can be configured to for example from 2300 to 6000MHz WiMAX frequency band, working.

Antenna structure 2000 comprises two antenna elements 2001,2004, and each antenna element comprises wide unipole antenna.Connection Element 2002 is electrically connected antenna element.Groove (or other otch) 2005 is used to improve the input impedance matching on the 5000MHz.Exemplary design shown in the figure is optimized to cover the frequency from 2300MHz to 6000MHz.

Antenna structure 2000 can for example be made through metal stamping.For example, it can be made by the thick alcu alloy film of 0.2mm.Antenna structure 2000 comprises roughly and on the Connection Element 2002 of the center of the main body of this structure, to pick up characteristic 2003 that this characteristic can be picked up automatically-reached-placing in the assembling process and use.This antenna structure also refluxes with mounted on surface and assembles compatibility.The distributing point 2006 of this antenna is provided to the tie point of the radio circuit on the PCB, and takes on the support that is used for antenna structurally is installed to PCB.Additional contact point 2007 provides structural support.

Figure 20 C shows the test suite 2010 of the performance that is used to measure antenna 2000.This figure also shows the coordinate reference that is used for far-field pattern (far-field pattern).Antenna 2000 is installed on the PCB 2011 of the 30x88mm that represents the ExpressCard/34 device.The grounded part of PCB 2011 is attached to bigger sheet metal 2012 (size that has 165x254mm in this example) to be represented as the typical balancer size of notebook.Test port 2014,2016 on the PCB 2011 is connected to antenna through 50 ohm strip line.

Figure 20 D shows the VSWR that measures at test port 2014,2016 places.Figure 20 E shows the coupling (S21 or S12) that between these test ports, measures.This VSWR and coupling are that to stride wide frequency ranges (for example, 2300 to 6000MHz) advantageously be low.Figure 20 F shows the measured radiation efficiency according to test port 2014 (port one), 2016 (port 2) reference.Figure 20 G shows the correlation of being calculated between the antenna pattern that antenna pattern that exciting test port 2014 (port one) produced produced exciting test port 2016 (port 2).Radiation efficiency advantageously is high, and the correlation between directional diagram advantageously is low at the frequency place that is paid close attention to.Figure 20 H shows exciting test port 2014 (port ones) or test port 2016 (port 2) the far gain directional diagram that produces at the frequency place of 2500MHz.The equidirectional figure that Figure 20 I and 20J show respectively at frequency 3500MHz and 5200MHz place measures.In φ=0 or XZ plane and in θ=90 or XY plane, the directional diagram that draws from test port 2014 (port one) is different and complementary with the directional diagram that draws from test port 2016 (port 2).

Figure 21 A and 21B show the multi-mode antenna structure 2100 according to one or more alternate embodiments of the present invention.Antenna structure 2100 can also for example use in WiMAX USB softdog.This antenna structure can be configured to for example from 2300 to 2400MHz WiMAX frequency band, working.

Antenna structure 2100 comprises two antenna elements 2102,2104, and each antenna element comprises circuitous unipole antenna.Circuitous length has been confirmed centre frequency.The configuration that other are crooked such as helical coil and ring, also can be used to provide the electrical length of expectation.Exemplary design shown in the figure is optimized for the centre frequency of 2350MHz.Connection Element 2106 (shown in Figure 21 B) is electrically connected antenna element 2102,2104.The element coupling of lump two parts is provided at each antenna feed place.

This antenna structure can be the flexible print circuit (FPC) 2103 that is installed on the plastic carrier 2101 by flexible for example.This antenna structure can be assigned to create by the metallization of FPC 2103.Plastic carrier 2101 is provided for installation stitch or the syringe needle (pip) 2107 and the syringe needle 2105 that be used for FPC 2103 be fastened to carrier 2101 of antenna attachment to the PCB assembly (not shown).2103 metalized portion comprises exposed portions or pad 2108 so that electric contact of circuit on this antenna and this PCB.

In order to obtain higher centre frequency, can reduce the electrical length of element 2102,2104.Figure 22 A and 22B show multi-mode antenna structure 2200, and this structure Design is optimized for the centre frequency of 2600MHz.The electrical length of element 2202,2204 is shorter than the electrical length of the element 2102,2104 of Figure 21 A and 21B, because the metallization of the end of element 2202,2204 is removed, and has increased the width of these elements of feed terminal place.

Figure 23 A shows the test suite 2300 of the antenna 2100 that uses Figure 21 A and Figure 21 B, and the coordinate reference that is used for far-field pattern.Figure 23 B shows the VSWR that locates to measure at test port 2302 (port one), 2304 (port 2).Figure 23 C shows the coupling (S21 or S12) that between test port 2302 (port one), 2304 (port 2), measures.VSWR is that (for example, 2300 to 2400MHz) advantageously are low at the frequency place that is paid close attention to coupling.Figure 23 D shows the radiation efficiency that measures according to these test port institute references.Figure 23 E shows the correlation of being calculated between the antenna pattern that antenna pattern that exciting test port 2302 (port one) produced produced exciting test port 2304 (port 2).Radiation efficiency advantageously is high, and the correlation between directional diagram advantageously is low at the frequency place that is paid close attention to.Figure 23 F shows the far gain directional diagram that at the frequency place of 2400MHz exciting test port 2302 (port ones) or test port 2304 (port 2) are produced.In φ=0 or XZ plane and in θ=90 or XY plane, the directional diagram that draws from test port 2302 (port one) is different and complementary with the directional diagram that draws from test port 2304 (port 2).

Figure 23 G shows the VSWR that measures at the test port place of assembly 2300, and wherein antenna 2200 has replaced antenna 2100.Figure 23 H shows the coupling of between these test ports, measuring (S21 or S12).VSWR advantageously is low with being coupling in the frequency place (for example, 2500 to 2700MHz) that is paid close attention to.Figure 23 I shows the measured radiation efficiency that is referenced to according to these test ports.Figure 23 J shows the correlation of being calculated between the antenna pattern that antenna pattern that exciting test port 2302 (port one) produced produced exciting test port 2304 (port 2).Radiation efficiency advantageously is high, and the correlation between directional diagram advantageously is low at the frequency place that is paid close attention to.Figure 23 K shows the far gain directional diagram that at the frequency place of 2600MHz exciting test port 2302 (port ones) or test port 2304 (port 2) are produced.In φ=0 or XZ plane and in θ=90 or XY plane, the directional diagram that draws from test port 2302 (port one) is different and complementary with the directional diagram that draws from test port 2304 (port 2).

One or more further embodiment of the present invention turns to the purpose of (null steering) or beam position (beam pointing) to the technology that is used for beam pattern (beam pattern) control to be used for null value.When such technology is applied to traditional array antenna when (comprising the antenna element of opening with certain fractional value size interval of wavelength that separates), present each element of this array antenna with the signal that is the phase-shifted version of reference signal or waveform.For the uniform linear array with phase equal excitation, the beam pattern that is produced can be described with array factor F, and array factor F depends on the phase place and the interelement element spacing d of each discrete component.

$F=A_o\underset{n=0}{\overset{N-1}{\mathrm{\Σ}}}\exp \left[\mathrm{jn}(\mathrm{\β}d\cos \mathrm{\θ}+\mathrm{\α})\right]$

β=2 π/λ wherein, the total quantity of N=element, α=continuous interelement phase shift, and θ=from the angle of array axes.

Through with the phase place α value of being controlled to be α _i, the maximum of F can be adjusted to different directions θ _i, the direction of peak signal is broadcasted or is received in control thus.

Interelement in the traditional array antenna is common at interval on the order of magnitude of 1/4 wavelength, and antenna can closely be coupled, thereby has the identical polarization of being close to.Coupling advantageously reduces the coupling between the element, because possibly cause the design of array antenna and some problems of performance.For example; Such as pattern distortion with scanning blind spot problem (referring to Stutzman; Antenna Theory and Design (antenna theory and design); Wiley 1998 122-128 and 135-136, and 466-472 page or leaf) maximum gain that possibly can obtain because of the coupling of excessive interelement and to the element of giving determined number reduce occur.

The beam pattern control technology can advantageously be applied to all multi-mode antenna structures with the antenna element that is connected by one or more Connection Elements described herein, and its height that demonstrates between a plurality of distributing points is isolated.Phase potential energy between the port at high isolated antennas structure place is used for the control antenna directional diagram.Have been found that when using antenna to form array,, can realize higher peak gain at assigned direction as the result of the coupling that reduces between distributing point as simple wave beam.Correspondingly, the high isolated antennas structure that is the phase control of the carrier signal of giving its feed terminal according to the utilization according to various embodiment can realize bigger gain in the selected direction.

In the handset applications of spaced far between antenna less than 1/4 wavelength, the effect that intercouples in the traditional antenna reduces the radiation efficiency of array, and has therefore reduced attainable maximum gain.

Be provided to phase place through control, can control the direction of the maximum gain that this antenna pattern produces according to the carrier signal of each distributing point of the high isolated antennas of various embodiment.The gain advantage, the 3dB that for example beam steering obtained is that fix and orientation equipment is particularly advantageous in being used by the portable set of user's STOCHASTIC CONTROL at beam pattern.Like diagram, for example as show according to the directional diagram of various embodiment control (pattern control) and install shown in the schematic block diagram of Figure 24 of 2400, phase-shifter 2402 is applied to relative phase shift α the RF signal that is applied to each antenna feed 2404,2408.These signals are fed to the corresponding antenna port of antenna structure 2410.

Phase-shifter 2402 can comprise standard phase shift parts, such as for example electric controlled phase shift apparatus or standard phase-shift network.

Figure 25 A-25G provides for the different phase difference α between presenting to two of antenna, the comparison of the antenna pattern that the high isolated antennas array of dipole antenna array that closely isolated 2-D is traditional and 2-D is according to various embodiments of the present invention produced.In Figure 25 A-25G, show curve at the antenna pattern at θ=90 degree places.Solid line among each figure is represented to present the antenna pattern that the discrete component antenna is produced according to the segregate of various embodiment, and dotted line is represented two one pole antenna patterns that traditional antenna produces that separate of the distance of the spaced apart width that equals the segregate feed structure of discrete component.Therefore, traditional antenna is the identical size of cardinal principle with high isolated antennas.

In all situations shown in the figure, compare with two conventional dipole antenna of separating according to the peak gain that high isolated antennas produced of each embodiment and to have produced bigger gain margin, the azimuth control to beam pattern is provided simultaneously.This behavior makes to be needed or expects the transmission of additional gain or receive to use high isolated antennas to become possibility in the application on specific direction.This direction can be controlled through the relative phase between adjustment drive point signal.This is for the portable set advantageous particularly that need energy directional be arrived acceptance point (such as for example base station).When phasing in a similar fashion, the high isolated antennas of combination is compared the advantage that provides bigger with two independent traditional antenna elements.

Shown in Figure 25 A,, show bigger gain with uniform azimuth patterns (θ=90) according to the combination dipole antenna of each embodiment for α=0 (phase difference of 0 degree).

Shown in Figure 25 B, for α=30 (phase difference of the degree of 30 between the distributing point), show bigger peak gain (at φ=0 place) according to the combination dipole antenna of each embodiment, have asymmetric azimuth patterns (figure of θ=90).

Shown in Figure 25 C, (phase difference of 60 between distributing point degree shows bigger peak gain (at φ=0 place) according to the combination dipole antenna of each embodiment, has the azimuth patterns (figure of θ=90) of skew for α=60.

Shown in Figure 25 D, for α=90 (phase difference of the degree of 90 between the distributing point), show even bigger peak gain (at φ=0 place) according to the combination dipole antenna of each embodiment), have the azimuth patterns (figure of θ=90) of skew.

Shown in Figure 25 E; For α=120 (120 between the distributing point degree phase difference), show the azimuth patterns (θ=90 figure) that bigger peak gain (at φ=0 place) has skew, bigger episternites (at φ=180 places)) according to the combination dipole antenna of each embodiment.

Shown in Figure 25 F; For α=150 (phase difference of the degree of 150 between the distributing point); Combination dipole antenna according to each embodiment shows bigger peak gain (at φ=0 place), has the azimuth patterns (θ=90 figure) of skew, even bigger episternites (at φ=180 places).

Shown in Figure 25 G, for α=180 (phase difference of the degree of 180 between the distributing point), show bigger peak gain (at φ=0&180 place) according to the combination dipole antenna of each embodiment, have the azimuth patterns (figure of θ=90) of paired lobing.

If Figure 26 shows the The perfect Gain advantage that the high isolated antennas according to the combination of one or more embodiment that becomes with the phase angle differences between the distributing point of the aerial array of two distributing points is superior to two dipole antennas that separate.

The gain of the increase that is obtained through the directional diagram control of using according to the antenna structure with two parallel dipole antennas that connected by circuitous Connection Element of one or more embodiment of the present invention can be used for improving the scope or the reliability of Radio Link.Alternatively, the gain of increase can obtain the radio link performance that is equal to the transmitted power that reduces for portable set or other equipment create conditions.For example, the average transmission gain improvement of controlling the 3dB that obtains from directional diagram is that transmitted power reduces 3dB, keeps identical link performance to create conditions simultaneously.Transmitted power to reduce aspect some be favourable.At first, portable radio machine need satisfy special absorption ratio (SAR) regulations restrict usually, and this regulations restrict possibly be difficult to satisfy under the situation of not sacrificing some performances.Corresponding the reducing that reduces under the situation of any sacrifice in performance not, to provide peak value SAR value of transmitted power.In addition, lower transmitted power has reduced the burden of output PA, thereby allows the design to the linearity of lower power and Geng Gao.In addition, the transmitted power that reduces is of value to the longer battery life of portable set or other equipment and lower heat radiation requirement.

Increase though the use of phase control has produced the expectation of far gain, yet the variation of phase excitation also possibly change the near field and influence the SAR value.In order to realize that clean SAR value reduces, the increase of antenna far gain should be greater than any increase of peak value SAR value.Through experiment, the applicant has been found that in fact, compares with far gain, and the change of SAR value is less relatively on phase place.

Figure 30 shows the exemplary USB softdog with two-port antenna structure of the directional diagram control application that is used for the 1900MHz frequency band.Shown in figure 31; The determined SAR value of simulation of the configuration through being used for Figure 30 is relatively independent of the relative phase between the drive point signal that is used for directional diagram control; So that can both realize the benefit that reduces of measured peak value SAR value, the perfect square parallactic angle control to beam pattern is provided simultaneously for all relative phase values.

The technological selection ground that is used to reduce near-field thermal radiation level and SAR value described herein isolates the multi-mode antenna structure with above-described height with Connection Element that antenna element is electrically connected and uses.Yet these technology can also more generally be used with such aerial array: this aerial array comprises and can handle on the phase place so that a plurality of radiant elements of the gain on antenna pattern control and the increase preferential direction to be provided.

Further embodiment of the present invention to lean on each other at given frequency range place provide between the multiband antenna port of the utmost point near-earth work height of increase to isolate the multi-mode antenna structure.In these embodiment, the frequency band restrain tank integrated with in one of antenna element of this antenna structure with this groove by be tuned to the frequency place coupling that reduces is provided.

Figure 27 A schematically shows simple double frequency-band branch line unipole antenna 2700.Antenna 2700 comprises frequency band restrain tank 2702, and frequency band restrain tank 2702 defines two branch's resonators 2704,2706.This antenna is driven by signal generator 2708.Depend on antenna 2700 driven frequencies, on two branch's resonators 2704,2706, realize various CURRENT DISTRIBUTION.

The physical size of groove 2702 is limited wide Ws and long Ls, shown in Figure 27 A.When driving frequency satisfies the condition of Ls=1o/4, the resonance that becomes of the characteristic of groove.At this some place, CURRENT DISTRIBUTION in the segment set of the shortening of this groove is shown in Figure 27 B.

Flow through the electric current approximately equal of branch's resonator 2704,2706 and in the opposite direction along the side of groove 2702.This causes antenna structure 2700 to turn round with the similar mode of branch line band stop filter 2720 (schematically illustrated in Figure 27 C), and its input impedance with antenna converts into downwards and is starkly lower than the demarcation source impedance.This big impedance does not match and causes very high VSWR (shown in Figure 27 D and 27E), and therefore causes desired frequency to suppress.

This frequency restrain tank technology can be applied to having two (or more a plurality of) lean on each other the antenna system of utmost point near-earth antennas operating element, one of them antenna element need transmit the signal of expected frequency and the another one antenna element does not need.In one or more embodiments, one in these two antenna elements comprises the frequency band restrain tank, and another does not comprise.Figure 28 schematically shows antenna structure 2800, and it comprises first antenna element 2802, second antenna element 2804 and Connection Element 2806.Antenna structure 2800 comprises respectively the port 2808 and 2810 at antenna element 2802 and 2804 places.In this example, the antenna structure 2802 at signal generator drive ports 2808 places, and instrument is coupled in the electric current of port 2810 with measurement port 2810 places.Yet, should be appreciated that arbitrary port or two ports can be driven by signal generator.Antenna element 2802 comprises frequency band restrain tank 2812, and frequency band restrain tank 2812 defines two branch's resonators 2814,2816.In this embodiment, branch's resonator comprises the main transmitting section of this antenna structure, and antenna element 2804 comprises the diversity reception part of this antenna structure.

Because big not the matching in the port of the antenna element with frequency band restrain tank 2,812 2802, intercoupling between it and the diversity reception antenna element 2804 (it is indeed match at groove resonance frequency place) will be very little and will be caused high relatively isolation.

Figure 29 A is the perspective view according to the multi-mode antenna structure 2900 of one or more further embodiment of the present invention, and multi-mode antenna structure 2900 comprises multiband diversity reception antenna system, and this system utilizes the frequency band restrain tank technology in the GPS frequency band.(the GPS frequency band is 1575.42MHz, and bandwidth is 20MHz).Antenna structure 2900 is formed on the flexible membrane dielectric substrate 2902, and this substrate 2902 is formed the layer on the dielectric carrier 2904.Antenna structure 2900 is included in the GPS frequency band restrain tank 2906 on the main transmitting antenna element 2908 of antenna structure 2900.Antenna structure 2900 also comprises diversity reception antenna element 2910 and the Connection Element 2912 that connects diversity reception antenna element 2910 and main transmit antenna element 2908.The gps receiver (not shown) is connected to diversity reception antenna element 2910.In order to minimize the antenna coupling that comes autonomous transmitting antenna element 2908 substantially and to maximize diversity antenna radiation efficiency substantially at these frequency places, main antenna element 2908 comprise frequency band restrain tank 2906 and by be tuned near the electric quarter-wave of GPS band center.Diversity reception antenna element 2910 does not comprise such frequency band restrain tank, but comprises and suitably match the main antenna source impedance so that will be the gps antenna element of maximum substantially power delivery between it and gps receiver.Although antenna element 2908 and 2910 both lean on utmost point near-earth coexistence; The high VSWR that brings by groove 2906 at main transmitting antenna element 2908 places reduced groove 2906 by be tuned to the frequency place to the coupling of main antenna element source resonance, and so antenna element 2908 and 2910 isolation at GPS frequency place between the two is provided.Two antenna elements 2908 in the resulting GPS frequency band, not matching even as big as these elements of de between 2910 to satisfy the insulation request of the system design shown in Figure 29 B and Figure 29 C.

In the antenna structure according to each embodiment of the present invention as herein described, antenna element and Connection Element preferably form single integrated irradiation structure so that the signal excitation entire antenna structure that is fed to arbitrary port with as a whole rather than the irradiation structure that separates carry out radiation.So, the techniques described herein provide the isolation of antenna port and have not used the de network at the antenna feed point place.

Although should be appreciated that and described the present invention according to certain embodiments, however previous embodiment only provide as explanation, and do not limit or limit scope of the present invention.

Various other embodiment that include but not limited to following each embodiment also within the scope of the claims.For example, the element of various multi-mode antenna structures described herein or parts can further be divided into other parts or be combined together to form less components to carry out identical functions.

After having described the preferred embodiments of the present invention, obvious, can make and revise and do not deviate from the spirit and scope of the present invention.

Claims (22)

1. near-field thermal radiation and method of special absorption ratio (SAR) value that reduces in the communication equipment; Said communication equipment comprises sending with the multi-mode antenna structure of receiving electromagnetic signals and is sent to said antenna structure and from the circuit of the signal of said antenna structure transmission, said antenna structure comprises: a plurality of antenna ports that operationally are coupled to said circuit with being used to handle; A plurality of antenna elements, each antenna element operationally are coupled to the different antennas port in the said antenna port; And one or more Connection Elements; Said one or more Connection Element with isolated each antenna element of the antenna port that is coupled to it on the position be electrically connected said antenna element; To form single irradiation structure and so that the adjacent antenna elements that the current direction on antenna element connects and walk around the said antenna port that is coupled in said adjacent antenna elements substantially; The electric current that flows through a said antenna element and said adjacent antenna elements equates on amplitude substantially; So that at given desired signal frequency range place by the antenna mode of antenna port excitation with by pattern that another antenna port encouraged electrical isolation substantially, and said antenna structure generates the different antennas directional diagram; Said method comprises:

Adjustment be fed to the relative phase between the signal of adjacent antenna port of said antenna structure so that be fed to the signal of a said antenna port have with the signal different phase that is fed to said adjacent antenna port antenna pattern control to be provided and to increase the gain on the preferential direction of acceptance point; And

Use is lower than the transmitted power of the transmitted power of in the non-directional diagram control operation of said antenna structure, using so that the radio link performance that the acquisition of said communication equipment is equal to substantially; Wherein said acceptance point uses and compares the transmitted power that reduces with said non-directional diagram control operation, reduces said special absorption ratio thus.

2. the method for claim 1 is wherein adjusted relative phase between the signal and is comprised and use electric controlled phase shifts equipment to adjust the relative phase between the signal.

3. the method for claim 1 is wherein adjusted relative phase between the signal and is comprised and use phase-shift network to adjust the relative phase between the signal.

4. the method for claim 1 is wherein adjusted relative phase between the signal and is comprised that the phase place of the carrier signal that provides through each the antenna port place that is controlled in said a plurality of antenna port adjusts the relative phase between the signal.

5. the method for claim 1, wherein said communication equipment is cellular handset, PDA, wireless networking device or the data card that is used for PC.

6. the method for claim 1, wherein said antenna element comprise spiral coil, broadband flat shape, antenna component, circuitous shape, ring or inductance bypass form.

7. the method for claim 1, wherein said multi-mode antenna structure is included in the planar structure of making on the printed circuit board base board.

8. the method for claim 1, wherein said multi-mode antenna structure comprises the metal parts of punching press, said metal parts be included in said parts main body the center pick up characteristic to pick up and to place in the assembling process and use in automation.

9. the method for claim 1, wherein said multi-mode antenna structure comprise be installed on the plastic carrier or the plastic housing of equipment on flexible print circuit.

10. the method for claim 1, wherein said acceptance point is base station, portable terminal or router.

11. the method for claim 1, the relative phase of wherein adjusting between the signal comprises that the relative phase of dynamically adjusting between the signal that is fed to the adjacent antenna port is to be maintained to the communication link through optimizing basically of said acceptance point.

12. near-field thermal radiation and method of special absorption ratio (SAR) value that reduces in the communication equipment; Said communication equipment comprises the circuit that is used to send with the aerial array of receiving electromagnetic signals and is used to handle the signal that transmits and transmit from said aerial array to said aerial array; Said aerial array comprises a plurality of radiant elements, and each radiant element has the antenna port that operationally is coupled in said circuit; Said method comprises:

Adjustment be fed to the relative phase between the signal of said antenna port of said aerial array so that be fed to the signal of an antenna port have with the signal different phase that is fed to another antenna port antenna pattern control to be provided and to increase the gain on the preferential direction of acceptance point; And

Use is lower than the transmitted power of the transmitted power of in the non-directional diagram control operation of said aerial array, using so that the radio link performance that the acquisition of said communication equipment is equal to substantially; Wherein said acceptance point uses and compares the transmitted power that reduces with said non-directional diagram control operation, reduces said special absorption ratio thus.

13. method as claimed in claim 12 is wherein adjusted relative phase between the signal and is comprised and use electric controlled phase shifts equipment to adjust the relative phase between the signal.

14. method as claimed in claim 12 is wherein adjusted relative phase between the signal and is comprised and use phase-shift network to adjust the relative phase between the signal.

15. method as claimed in claim 12 is wherein adjusted relative phase between the signal and is comprised that the phase place of the carrier signal that provides through each the antenna port place that is controlled in said a plurality of antenna port adjusts the relative phase between the signal.

16. method as claimed in claim 12, wherein said communication equipment are cellular handset, PDA, wireless networking device or the data card that is used for PC.

17. method as claimed in claim 12, wherein said radiant element comprise spiral coil, broadband flat shape, antenna component, circuitous shape, ring or inductance bypass form.

18. method as claimed in claim 12, wherein said aerial array is included in the planar structure of making on the printed circuit board base board.

19. method as claimed in claim 12, wherein said aerial array comprises the metal parts of punching press, said metal parts be included in said parts main body the center pick up characteristic to pick up and to place in the assembling process and use in automation.

20. method as claimed in claim 12, wherein said aerial array comprise be installed on the plastic carrier or the plastic housing of equipment on flexible print circuit.

21. method as claimed in claim 12, wherein said acceptance point are base station, portable terminal or router.

22. method as claimed in claim 12, the relative phase of wherein adjusting between the signal comprises that the relative phase of dynamically adjusting between the signal that is fed to said antenna port is to be maintained to the communication link through optimizing basically of said acceptance point.

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