A kind of central shaft is to null-fill omnidirectional antenna device
Technical field
The present invention relates to communication antenna systems technology field, relate in particular to a kind of central shaft to null-fill omnidirectional antenna device.
Background technology
The conventional omnidirectional antenna using on Communications Market at present, although profile style is of all shapes and colors, the structure of its inside is similar substantially.Therefore also determined that its central shaft of conventional omnidirectional antenna is similar to the beam direction of directional diagram to angle etc.If conventional omnidirectional antenna only uses and substantially can meet the needs that cover use with the covering of community, road at some conventional communication base stations.If but at the aircraft of built on stilts certain altitude, in the particular application such as course line covering or the earth-space communication of radar guided missile of air line, due to the particularity of application scenario, the omnidirectional antenna of general communication has determined because it is structural in the axial zero degree angle of center of antenna that zero causes more greatly larger signal deletion deeply, as shown in Figure 1, central shaft generally upwarps angle or tilt angled down direction at zero degree or band to antenna pattern main lobe, thereby cannot meet that course line in aircraft or the air line of built on stilts certain altitude covers or the particular application such as the earth-space communication of radar guided missile in main beam upwards the axial zero degree angular range of message center internal upper part radiation space carry out the instructions for use of null-fill.
Summary of the invention
The object of the invention is to propose a kind of central shaft to null-fill omnidirectional antenna device, easily realize broadband operation, central shaft upwarps radiation and makes central shaft to null-fill to antenna pattern wave beam, make signal of communication upwards communicate by letter and to central shaft to zero deeply causing more greatly compared with the disappearance of large-signal and compensate in zero degree angle.
For reaching such object, the present invention by the following technical solutions:
A kind of central shaft, to null-fill omnidirectional antenna device, comprising: feeding network that omnidirectional antenna radiating element, centre pipe, coaxial feeder are done, passive coupling device, auxiliary antenna from central shaft to null-fill and standard 50 Ω interfaces for;
Described omnidirectional antenna device is made up of multiple radiating elements and is uniformity periodic arrangement and becomes coaxial conllinear battle array;
It is inner and evenly distributed that the feeding network that described coaxial feeder is done is arranged at described omnidirectional antenna radiating element, the phase control for described omnidirectional antenna device central shaft to the upwards null-fill of antenna pattern;
Described passive coupling device is arranged at described omnidirectional antenna radiating element bottom, for part signal is coupled and is assigned to the auxiliary antenna at top by coupler;
The described auxiliary antenna for axial null-fill is arranged at the top of described omnidirectional antenna device, compensates to null-fill for the signal distributing by described passive coupling device is carried out to central shaft.
Described omnidirectional antenna radiating element is tubular metal radiant body, forms uniformly periodically coaxial conllinear array by two metal sleeve oscillators and chokes sleeve pipe and multiple radiating element; The centre frequency of described two metal sleeve oscillators is respectively 1/4 λ and 1/5 λ, and wherein, λ is the operation wavelength of described metal sleeve oscillator.
The feeding network that described coaxial feeder is done is arranged at antenna radiation unit inside, each feeder line parallelly feeding is assigned to the periodically coaxial conllinear array of multiple radiating element composition homogeneities, and control the phase difference of described feeding network by adjusting the length of coaxial feeder between two or more radiating elements, thereby control the effect of secondary lobe null-fill.
Described passive coupling device is arranged at omnidirectional antenna radiating element central shaft on the position of the 0.8 times of centre wavelength distance in bottom, can control the amplitude distribution ratio of omnidirectional antenna radiating element and auxiliary antenna by adjusting the degree of coupling of passive coupling device.
Described central shaft is arranged at omnidirectional antenna radiating element central shaft on the position of the 0.8 times of centre wavelength distance in top to the auxiliary antenna of null-fill.
Adopt technical scheme of the present invention, easily realize broadband operation, elevation radiation patytern wave beam upwards upwarps and does the effect of central shaft to null-fill radiation, aerial signal is upwards communicated by letter, and adopt central shaft to null-fill technology, make up central shaft to the disappearance of the radiation signal of wave beam upwards in 0:00 direction figure angle, make the emittance of described antenna in the situation that of built on stilts certain altitude, also can realize more stable signal and cover communication.
Brief description of the drawings
Fig. 1 is the test result schematic diagram of the omnidirectional antenna elevation radiation patytern used of existing general communication.
Fig. 2 is the structural representation of the central shaft that provides of the embodiment of the present invention to null-fill omnidirectional antenna device.
Fig. 3 is the test result schematic diagram that the omnidirectional antenna in the embodiment of the present invention upwarps by controlling feeding network phase place official post elevation radiation patytern main lobe.
Fig. 4 is that the omnidirectional antenna control feeding network phase difference in the embodiment of the present invention is realized secondary lobe null-fill on elevation radiation patytern and used the elevation radiation patytern test result schematic diagram of central shaft to the central shaft of surveying after null-fill auxiliary antenna to null-fill effect.
Embodiment
Further illustrate technical scheme of the present invention below in conjunction with accompanying drawing and by embodiment.
Fig. 2 is the structural representation of a kind of central shaft of providing of the embodiment of the present invention to null-fill omnidirectional antenna device, and this omnidirectional antenna comprises: by the radiating element 1 of the periodically coaxial conllinear array of multiple radiating element composition homogeneities, feeding network 2 that coaxial feeder is done, centre pipe 3, passive coupling device 4, auxiliary antenna 5 from central shaft to null-fill and standard 50 Ω interfaces 6 for.
The described position that is arranged at approximately 0.8 times of centre wavelength of the radiating element 1 central shaft distance certain to top for central shaft to the auxiliary antenna 5 of null-fill, describedly connect by drawing feeder line with described passive coupling device 4 to the auxiliary antenna 5 of null-fill for central shaft, the radiating element 1 of the periodically coaxial conllinear array of described multiple radiating element composition homogeneities is electrically connected with the coupling port of described passive coupling device 4 by the feeder line of drawing of feeding network 2.Described passive coupling device 4 is the auxiliary antenna 5 to the central shaft at top to null-fill for the power coupling distributing signal in installing.
Described radiating element 1 carries out phase control by feeding network 2, and the elevation radiation patytern main lobe of omnidirectional antenna is upwarped.Described radiating element 1 is carried out to phase control, control the phase difference of described feeding network 2 by the length of adjusting coaxial feeder between two or more radiating elements 1, thereby control the effect of secondary lobe null-fill.The length of described coaxial feeder calculates according to the operating frequency of described omnidirectional antenna device and wavelength.
Be the test result that thereby described radiating element 1 is changed to the phase difference aft antenna elevation radiation patytern of feeding network 2 by changing the length of coaxial feeder as shown in Figure 3, from result, can find out that antenna elevation radiation patytern main lobe upwarps.
The described radiating element 1 by the periodically coaxial conllinear array of multiple radiating element composition homogeneities is preferably tubular metal radiating element, forms a radiating element by two metal sleeve oscillators and chokes sleeve pipe.The centre frequency of described two metal sleeve oscillators is respectively 1/4 λ and 1/5 λ,, λ is the operation wavelength of described metal sleeve oscillator.
In order to make central shaft to reaching better filling effect, describedly carry out central shaft and augment to null-fill by the be coupled part electromagnetic wave that obtains of passive coupling device to the auxiliary antenna of null-fill for central shaft.
In another preferred embodiment, described for central shaft to axial null-fill compensation antenna centered by the auxiliary antenna 5 of null-fill, secondary lobe on antenna is realized to the effect of central shaft to null-fill amplification.As shown in Figure 4, to null-fill auxiliary antenna, central shaft is filled the test result of aft antenna elevation radiation patytern to zero point by top, the position central shaft of approximately 0.8 times of centre wavelength of radiating element 1 that is arranged on the periodically coaxial conllinear array of the uniformity that is made up of multiple radiating elements of distance, directional diagram main lobe upwarps and central shaft has upwards carried out effective filling zero point as can be seen from the results.
The key technical indexes of the omnidirectional antenna device in the embodiment of the present invention is as follows:
Frequency range: 962~1057MHz;
Gain: 9dBi;
Upper plane secondary lobe null-fill :-25dB;
Vertical lobe width: 7 °~8 °;
Voltage standing wave ratio :≤1.5;
Polarization mode: perpendicular polarization.
Implement technical scheme of the present invention, there is following technique effect; Easily realize broadband operation, secondary lobe null-fill on center of antenna axial direction figure, main beam upwarps radiation, aerial signal is upwards communicated by letter, and adopt central shaft to null-fill technology, supplement central shaft is to the disappearance of the radiation signal of wave beam upwards in 0:00 direction figure angle, thereby makes this omnidirectional antenna emittance in the situation that of built on stilts certain altitude, also can realize that more stable signal covers or course line covers communication.
The above; be only preferably embodiment of the present invention, but protection scope of the present invention is not limited to this, any people who is familiar with this technology is in the disclosed technical scope of the present invention; the variation that can expect easily or replacement, within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection range of claim.