Patent Publication Number: US-11050131-B2

Title: Antenna mounting base and antenna

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a national phase entry under 35 USC § 371 of International Application PCT/CN2018/096490, filed Jul. 20, 2018, and published as WO 2019/119798 A1, on Jun. 27, 2019, not in English, which claims the benefit of and priority to Chinese Patent Application No. 201711386649.1, filed on Dec. 20, 2017, the entire disclosures of which are incorporated herein by reference. 
     FIELD 
     The present disclosure relates to a technology field of antennas, particularly to an antenna mounting base and an antenna. 
     BACKGROUND 
     The existing multi-frequency circular polarization GNSS (Global Navigation Satellite System) antennas are commonly in the form of laminated microstrip antennas, metal half-wave dipole antennas, helical antennas, and etc. Technically, both the laminated microstrip antennas and the metal half-wave dipole antennas realize a certain function in terms of a bandwidth, but there are still many problems. 
     For the laminated microstrip antenna, the bandwidth advantage is not obvious, a beam width of the antenna is not wide, gain at a low elevation angle is poor, and requirement for consistency makes structure assembly more difficult and cost higher. The metal half-wave dipole can realize a broadband form, but the beam width is not wide, the gain at the low elevation angle is poor, the structure assembly is complicated, and the cost is high. Multi-frequency helical antenna has a wide beam width but low gain. 
     In the use of GNSS antenna, the above problems of poor gain at the low elevation angle directly lead to a problem of relatively poor anti-multipath effect, that is, the ranging error of antenna increases, resulting in poor positional accuracy. 
     SUMMARY 
     (I) Technical Problems to be Solved 
     In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides an antenna mounting base and an antenna. 
     (II) Technical Solutions 
     In view of this, in a first aspect, the present disclosure provides an antenna mounting base including an antenna substrate, a fixing plate and an annular reflective plate, wherein, 
     the antenna substrate is of a bowl-shaped structure, and an edge of an opening of the bowl-shaped structure is fixed to the fixing plate; the annular reflective plate stands on the fixing plate and is fixed to the fixing plate; the annular reflective plate and the antenna substrate are located at the same side of the fixing plate; 
     a feed support base is provided inside the bowl-shaped structure. Alternatively, the antenna substrate includes a mounting flat plate and four mounting inclined plates, wherein, 
     four mounting inclined plates are uniformly distributed around the mounting flat plate; 
     a first side edge of the mounting inclined plate is fixed to an edge of the mounting flat plate; a second side edge of the mounting inclined plate is fixed to the fixing plate, the first side edge and the second side edge being opposite in position; 
     an included angle is formed between the mounting inclined plate and the mounting flat plate. 
     Alternatively, four threading through holes are uniformly arranged in the mounting flat plate, and the feed support base includes four cable mounting channels, the position of each cable mounting channel corresponding to the position of one threading through hole. 
     Alternatively, four open slots are arranged on the annular reflective plate; 
     the four open slots divide the circumference of the annular reflective plate equally, and the center of each open slot corresponds to the center between the two mounting inclined plates. 
     Alternatively, the fixing plate is annular; 
     the edge at the opening of the bowl-shaped structure is fixed to an inner edge of the annular fixing plate; 
     the annular reflective plate is fixed to an outer edge of the annular fixing plate, the annular reflective plate being perpendicular to the fixing plate. 
     Alternatively, further including a bottom plate, wherein, 
     the bottom plate is fixed to the fixing plate, and the bottom plate and the antenna substrate are respectively located on different sides of the fixing plate; 
     a mounting through hole is arrange on the bottom plate, the position of the mounting through hole corresponding to the position of the feed support base. 
     In a second aspect, the present disclosure provides an antenna including an antenna mounting base according to the first aspect, further including a tuning director, a feed network, a reflector plate and a radiating sheet, wherein, 
     four fixing columns are arranged on the outer surface of the mounting flat plate of the antenna mounting base, and the four fixing columns are uniformly distributed on the mounting flat plate; 
     the tuning director is connected to an outer surface of the bottom of the bowl-shaped structure of the antenna substrate through a plurality of fixing columns, and an interval is arrange between the tuning director and the antenna substrate; the radiating sheet is fixed on the outer surface of the bowl-shaped structure of the antenna substrate; 
     the reflector plate is fixed on the annular reflective plate and is provided with at least one open slot; 
     the feed network is mounted in the feed support base, and the feed network is electrically connected to the radiating sheet. 
     Alternatively, there are four radiating sheets in the antenna, wherein, 
     each radiating sheet includes a first sub-part and a second sub-part, wherein the first sub-parts of the four radiating sheets are all located on the mounting flat plate and are provided with intervals with each other, the first sub-parts of the four radiating sheets being equal in area and being all triangular; 
     the first sub-part of each radiating sheet is provided with a wiring through hole and a fixing column through hole for passing through the fixing column; 
     the areas of the second sub-parts of the four radiating sheets are equal and are respectively located on different mounting inclined plates, the second sub-parts are composed of rectangles and triangles, the first side edge of the rectangle is connected to the long side of the triangle in the first sub-part, and the other side edge of the rectangle opposite to the first side edge is connected to the long side of the triangle of the second sub-part. 
     Alternatively, four open slots are arranged on the reflector plate, and the positions of the four open slots respectively correspond to the interval between the four radiating sheets, such that the reflector plates between adjacent open slots respectively correspond to one reflector plate. 
     Alternatively, the feed network includes two pairs of coaxial cables and a 90° phase shifter, wherein, 
     two pairs of coaxial cables are staggered in the feed support base; the 90° phase shifter and two pairs of coaxial cable are respectively located on different sides of the bottom plate; 
     each pair of coaxial cables includes a first coaxial cable and a second coaxial cable, wherein the outer conductors of the first coaxial cable and the second coaxial cable are respectively connected to one radiating sheet through the wiring through hole, and the radiating sheets connected to the two pairs of coaxial cables are staggered; the end of the inner conductor of the first coaxial cable is in a broken circuit; the inner conductor of the second coaxial cable is electrically connected to the 90° phase shifter. 
     Alternatively, the tuning director is a metal plate, and the shape of the tuning director is circular; 
     and/or; 
     the radiating sheet is a printed metal layer arranged on the outer surface of the antenna substrate; 
     and/or, 
     the reflector plate is a printed metal layer arranged on the outer surface of the annular reflective plate, and the shape of the reflector plate is consistent with the shape of the annular reflective plate. 
     (III) Beneficial Effects 
     In comparison with existing product technology, the above technical solutions provided by the embodiments of the present disclosure have the following advantages: 
     In comparison with existing product technology, the antenna provided by the embodiments of the present disclosure is simple to assemble, and has stronger structural consistency. The radiating sheet can be directly printed on the outer surface of the antenna substrate, and the feed coaxial cable can be directly attached to the antenna substrate when the radiating sheet and the feed coaxial cable are mounted. In addition, the antenna substrate, the fixing plate and the annular reflective plate in the antenna mounting base can be integrally formed, in such a manner that the supporting thickness of the substrate on the back surface of the radiating sheet is thin when used as an antenna, thereby reducing the dielectric loss of the antenna and improving the low gain at a low elevation angle of the antenna. 
     According to the antenna provided by the embodiments of the disclosure, in actual application, the beam width is adjustable, and the product body has strong adaptability; the reflector plate on the annular reflective plate is mainly used for adjusting the beam width and the return loss; in actual application, the current distribution mode can be changed by adjusting the height on the annular reflective plate, i.e. adjusting the width of the reflector plate, such that the adjustment of the beam width and the return loss can be realized, in such a manner that the required beam width and the smaller return loss can be obtained under different use conditions, and further the required low gain at a low elevation angle and beam width can be obtained. 
     In addition, since the feed network adopts a broadband compensation branch conductor balun feed network, the first coaxial cable  70  and the second coaxial cable  71  of the feed network are a group, and the first coaxial cable  70  and the second coaxial cable  71  are connected as inner conductors, and the outer conductors are respectively connected to the aligned radiating sheet  9 , that is, connected to the radiating sheet. The second coaxial cable  71  is a direct feed connection line, with an input impedance of 50Ω, the first coaxial cable  70  is in a broken circuit at the end of the inner conductor, with an impedance of 35Ω, and the length of the first coaxial cable  70  can be adjusted according to the designed frequency band adjustment, so that the current balance of the antenna is good, and the impedance matching bandwidth is adjustable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view illustrating an antenna according to embodiments of the present disclosure. 
         FIG. 2  is a schematic view illustrating a back surface according to  FIG. 1 . 
         FIG. 3  is a top view according to  FIG. 1 . 
         FIG. 4  is a schematic sectional view illustrating a plane C-C according to  FIG. 3 . 
         FIG. 5  is a right view according to  FIG. 1 . 
         FIG. 6  is a rear view according to  FIG. 3 . 
         FIG. 7  is a schematic view illustrating an antenna mounting base according to embodiments of the present disclosure. 
         FIG. 8  is a schematic view illustrating a radiating sheet. 
         FIG. 9  is schematic view illustrating the antenna mounting base when the radiating sheet is mounted. 
     
    
    
     DETAILED DESCRIPTION 
     In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, reference will be made clearly and completely technical solutions in the embodiments of the present disclosure with accompanying drawings. Obviously, the embodiments described here are only part of the embodiments of the present disclosure and are not all embodiments of the present disclosure. Based on the embodiments of the present disclosure, other embodiments obtained by those skilled in the art without creative labor are within scope of the present disclosure. 
       FIG. 1  is a schematic view illustrating an antenna according to embodiments of the present disclosure.  FIG. 2  is a schematic view illustrating a back surface according to  FIG. 1 .  FIG. 3  is a top view according to  FIG. 1 .  FIG. 4  is a schematic sectional view illustrating a plane C-C according to  FIG. 3 .  FIG. 5  is a right view according to  FIG. 1 .  FIG. 6  is a rear view according to  FIG. 3 . 
       FIG. 7  is a schematic view illustrating an antenna mounting base according to embodiments of the present disclosure.  FIG. 8  is a schematic view illustrating a radiating sheet.  FIG. 9  is schematic view illustrating the antenna mounting base when the radiating sheet is mounted. 
     The antenna provided by the embodiments of the present disclosure includes an antenna mounting base and an electrical part. 
     In a first aspect, as illustrated in  FIGS. 1-9 , the embodiments of the present disclosure provide an antenna mounting base, and the antenna mounting base includes an antenna substrate  1 , a fixing plate  2  and an annular reflective plate  3 . 
     The antenna substrate  1  is of a bowl-shaped structure, specifically a groove, such as a circular groove or a square groove, and etc. The antenna substrate  1  as a main carrier of the antenna is used for a radiating sheet to be mounted, and normally, the radiating sheet is mounted on an outer surface of the bowl-shaped structure of the antenna substrate  1 . 
     As illustrated in  FIG. 4 , the antenna substrate  1  includes a mounting flat plate  13  and four mounting inclined plates  14 , the four mounting inclined plates  14  are uniformly distributed around the mounting flat plate  13 ; and a hollow hole  10  is arranged between any two mounting inclined plates  14 . 
     A first side edge of the mounting inclined plate  14  is fixed to an edge of the mounting flat plate  13 ; a second side edge of the mounting inclined plate  14  is fixed to the fixing plate  2 , the first side edge and the second side edge are opposite, and an included angle is defined between the mounting inclined plate  14  and the mounting flat plate  13 . A structure including five plates of one mounting flat plate  13  and four mounting inclined plates  14  is formed. 
     As illustrated in  FIG. 7 , generally, an antenna radiating surface is located on an outer surface of the mounting flat plate  13  of the antenna substrate  1 . In order to facilitate electrical connection between the assembled antenna radiating surface and an inside of the antenna substrate  1 , four threading through holes  15  are uniformly arranged in the mounting flat plate. 
     As illustrated in  FIGS. 1, 6 and 7 , an edge at an opening of the bowl-shaped structure is fixed to the fixing plate  2 , and the annular reflective plate  3  stands on the fixing plate  2  and is fixed to the fixing plate  2 . 
     In an embodiment of the present disclosure, the fixing plate  2  may be annular. The edge at the opening of the bowl-shaped structure is fixed to an inner edge of the annular fixing plate  2 . The annular reflective plate  3  is fixed to an outer edge of the annular fixing plate  2 , and the annular reflective plate  3  is perpendicular to the fixing plate  2 . 
     In the embodiments of the present disclosure, the mounting flat plate  13  and the mounting inclined plate  14  of the antenna substrate  1  may be integrally injection molded, and the antenna substrate  1 , the fixing plate  2 , and the annular reflective plate  3  may all be integrally injection molded. Furthermore, the antenna substrate  1 , the fixing plate  2 , and the annular reflective plate  3  may be made of high molecular polymers, for example plastic products such as polyethylene. 
     The annular reflective plate  3  is used for installation and support of the reflector plate. In the embodiments of the present disclosure, the annular reflective plate  3  may be a plate of a consistent width, or at least one open slot  31  may be provided in the annular reflective plate  3 . As illustrated in  FIGS. 1, 3, 4 and 6 , four open slots  31  are arranged on the annular reflective plate  3 , and the position of each open slot  31  corresponds to the interval between two adjacent mounting inclined plates. Further, the four open slots  31  divide the circumference of the annular reflective plate equally, that is, the position of each open slot  31  corresponds to the position of one hollow hole  10  respectively, in such a manner that each mounting inclined plate corresponds to the side wall of a section of annular reflective plate  3 . The joint of two adjacent mounting inclined plates is provided with open slots  31 , and the depth of the open slots is smaller than the width of the side wall of the annular reflective plate  3 . In specific applications, the width of the side wall of the annular reflective plate  3  can be set to different sizes in advance according to antenna requirements. 
     As illustrated in  FIG. 2 , the inner surface of the bottom of the bowl-shaped structure is provided with a feed support base  11  for mounting the electrical part of the antenna. As illustrated in  FIG. 2 , four cable mounting channels  16  are provided in the feed support base  11 , and each cable mounting channel  16  corresponds to one threading through hole  15 . 
     In other embodiments of the present disclosure, as illustrated in  FIGS. 4, 5 and 6 , the antenna mounting base may further include a bottom plate  5 . 
     The bottom plate  5  is fixed to the fixing plate  2  by bolts  51 , and the bottom plate  5  and the antenna substrate  1  are respectively located on different sides of the fixing plate  2 . 
     A mounting through hole is arrange on the bottom plate  5  (not illustrated in the figure), and the position of the mounting through hole corresponds to the position of the feed support base. 
     In comparison with existing product technology, the antenna provided by the embodiments of the present disclosure is simple to assemble, and has stronger structural consistency. The radiating sheet can be directly printed on the outer surface of the antenna substrate, and the feed coaxial cable can be directly attached to the antenna substrate when the radiating sheet and the feed coaxial cable are mounted. In addition, the antenna substrate, the fixing plate and the annular reflective plate in the antenna mounting base can be integrally formed, in such a manner that the supporting thickness of the substrate on the back surface of the radiating sheet is thin when used as an antenna, thereby reducing the dielectric loss of the antenna and improving the low gain at a low elevation angle of the antenna. 
     In a second aspect, the embodiments of the present disclosure provide an antenna, as illustrated in  FIGS. 1-9 , including a tuning director  6 , a feed network (not labeled in the figure), a reflector plate (not labeled in the figure), and a radiating sheet  9 , and the antenna mounting base described in the first aspect. 
     As illustrated in  FIGS. 4, 5 and 7 , in the embodiments of the present disclosure, a plurality of fixing columns  12  are provided on the outer surface of the mounting flat plate  13  of the antenna substrate  1 , optionally four fixing columns, and the four fixing columns  12  are uniformly distributed on the mounting flat plate. The tuning director  6  is connected to the outer surface of the bottom of the bowl-shaped structure of the antenna substrate  1  through a plurality of fixing columns  12 , and an interval is arranged between the tuning director  6  and the antenna substrate  1 . 
     The radiating sheet  9  is fixed on the outer surface of the bowl-shaped structure of the antenna substrate  1 ; the reflector plate is fixed on the annular reflective plate  3  (both inner and outer surfaces); the feed network is mounted in the feed support base  11 , and the feed network is electrically connected to the radiating sheet  9 . 
     As illustrated in  FIGS. 8 and 9 , the hexagonal pattern filled in the figure is only for the convenience of distinguishing the radiating sheet from the antenna base after the radiating sheet is mounted, that is, the hexagonal pattern is a filling pattern on the radiating sheet, and is not the structure or shape of the radiating sheet  9 . The radiating sheets  9  include four plates, each radiating sheet includes a first sub-part  91  and a second sub-part  92 . The first sub-parts  91  of the four radiating sheets are all located on the mounting flat plate  13  and are provided with intervals with each other and insulated from each other, and the first sub-parts  91  of the four radiating sheets  9  are equal in area, that is, as illustrated in  FIG. 8 , the first sub-parts  91  of the four radiating sheets  9  are all triangular. 
     The first sub-part  91  of each radiating sheet is provided with a wiring through hole  93  and a fixing column through hole  94  for passing through the fixing column. The areas of the second sub-parts of the four radiating sheets  9  are equal and are respectively located on different mounting inclined planes. Further, the second sub-parts are composed of rectangles and triangles, the first side of the rectangle is connected to the long side of the triangle in the first sub-part, and the other side of the rectangle opposite to the first side is connected to the long side of the triangle in the second sub-part. 
     In the embodiments of the present disclosure, the feed network may adopt a compensation branch conductor balun feed network. As illustrated in  FIGS. 2 and 4 , the feed network may include two pairs of coaxial cables and a 90° phase shifter  72 , the two pairs of coaxial cables are staggered in the feed support base  11 , i.e., two cables in the same pair of coaxial cables are not adjacent to each other, also known as two pairs of coaxial cables are orthogonally distributed in the feed support base  11 . Furthermore, the 90° phase shifter and the two pairs of coaxial cables are respectively located on different sides of the bottom plate. 
     Each pair of coaxial cables includes a first coaxial cable  70  and a second coaxial cable  71 , the outer conductors of the first coaxial cable  70  and the second coaxial cable  71  are respectively connected to one radiating sheet through the wiring through hole, and the radiating sheets connected to the two pairs of coaxial cables are staggered, that is, the radiating sheets connected to two cables of the same pair of coaxial cables are not adjacent to each other. 
     In addition, the end of the inner conductor of the first coaxial cable  70  is a broken circuit; the inner conductor of the second coaxial cable  71  is electrically connected to the 90° phase shifter. 
     In an embodiment of the present disclosure, the tune director is a metal plate, and the shape of the tuning director is circular. 
     In an embodiment of the present disclosure, the radiating sheet  9  is a printed metal layer arranged on the outer surface of the antenna substrate  1 . 
     In an embodiment of the present disclosure, the reflector plate is a printed metal layer arranged on the outer surface of the annular reflective plate, and the shape of the reflector plate is consistent with the shape of the annular reflective plate, that is, the reflector plate is also annular, and the open slot is also arranged on the reflector plate. 
     According to the antenna provided by the embodiments of the disclosure, in actual application, the beam width is adjustable, and the product body has strong adaptability; the reflector plate on the annular reflective plate is mainly used for adjusting the beam width and the return loss; in actual application, the current distribution mode can be changed by adjusting the height on the annular reflective plate, i.e. adjusting the width of the reflector plate, such that the adjustment of the beam width and the return loss can be realized, in such a manner that the required beam width and the smaller return loss can be obtained under different use conditions, and further the required low gain at a low elevation angle and beam width can be obtained. 
     In addition, since the feed network adopts a broadband compensation branch conductor balun feed network, the first coaxial cable  70  and the second coaxial cable  71  of the feed network are a group, and the first coaxial cable  70  and the second coaxial cable  71  are connected as inner conductors, and the outer conductors are respectively connected to the aligned radiating sheet  9 , that is, connected to the radiating sheet. The second coaxial cable  71  is a direct feed connection line, with an input impedance of 50Ω, the first coaxial cable  70  is in a broken circuit at the end of the inner conductor, with an impedance of 35Ω, and the length of the first coaxial cable  70  can be adjusted according to the designed frequency band adjustment, so that the current balance of the antenna is good, and the impedance matching bandwidth is adjustable. 
     It should be noted that the relational terms herein, such as “first” and “second”, are used only for differentiating one entity or operation, from another entity or operation, which, however do not necessarily require or imply that there should be any real relationship or sequence. Moreover, the terms “comprise”, “include” or any other variations thereof are meant to cover non-exclusive including, so that the process, method, article or device comprising a series of elements do not only comprise those elements, but also comprise other elements that are not explicitly listed or also comprise the inherent elements of the process, method, article or device. In the case that there are no more restrictions, an element qualified by the statement “comprises a . . . ” does not exclude the presence of additional identical elements in the process, method, article or device that comprises the said element. 
     The above description is only the specific embodiments of the present disclosure to enable those skilled in the art to understand or implement the present disclosure. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is not to be limited to the embodiments illustrated herein, but is to be accorded the widest scope consistent with the principles and novel features applied herein. 
     INDUSTRIAL APPLICABILITY 
     According to the antenna provided by the embodiments of the disclosure, in actual application, the beam width is adjustable, and the product body has strong adaptability; the reflector plate on the annular reflective plate is mainly used for adjusting the beam width and the return loss; in actual application, the current distribution mode can be changed by adjusting the height on the annular reflective plate, i.e. adjusting the width of the reflector plate, such that the adjustment of the beam width and the return loss can be realized, in such a manner that the required beam width and the smaller return loss can be obtained under different use conditions, and further the required low pitch angle gain and beam width can be obtained, thus having strong industrial practicability.