Patent Publication Number: US-2022224006-A1

Title: Antenna device

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to Chinese Patent Application No. 202111673932.9 filed with the China National Intellectual Property Administration (CNIPA) on Dec. 31, 2021, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     Embodiments of the present disclosure relate to the technical field of communications, and in particular to an antenna device. 
     BACKGROUND 
     A phased array antenna is an important radio device for transmitting and receiving electromagnetic waves, and the phased array antenna controls phases of radio frequency signals of antenna units in an array antenna through a phase shifter to change a radiation direction of the antenna to achieve the purpose of beam scanning. 
     An existing phased array antenna has the problem of large size and is not beneficial to the miniaturization application of the phased array antenna. 
     SUMMARY 
     The present disclosure provides an antenna device, reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     An embodiment of the present disclosure provides an antenna device. The antenna device includes an antenna unit and first connection lines, the antenna unit includes a first substrate and a second substrate disposed opposite to each other; a region where the first substrate and the second substrate overlap forms a phase shift region in a thickness direction of the first substrate; the second substrate includes a first step protruding from the phase shift region in a first direction, a side of the first step close to the first substrate is provided with multiple first pads arranged in a second direction, and the multiple first pads are disposed on a side of the second substrate close to the first substrate, and the first direction intersects the second direction; and each of the multiple first pads is connected to a respective one of the first connection lines, and the multiple first pads are configured to receive a drive signal output by an external driver circuit through the first connection lines. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a structural diagram of an antenna device according to an embodiment of the present disclosure; 
         FIG. 2  is a cross sectional view taken along an A-A′ direction of  FIG. 1 ; 
         FIG. 3  is a structural diagram of an antenna device in the related art; 
         FIG. 4  is a cross sectional view taken along a B-B′ direction of  FIG. 3 ; 
         FIG. 5  is a structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 6  is a cross sectional view taken along a C-C′ direction of  FIG. 5 ; 
         FIG. 7  is a structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 8  is a structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 9  is a partial structural diagram of an antenna device according to an embodiment of the present disclosure; 
         FIG. 10  is a cross sectional view taken along a D-D′ direction of  FIG. 9 ; 
         FIG. 11  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 12  is a cross sectional view taken along an E-E′ direction of  FIG. 11 ; 
         FIG. 13  is a structural diagram of a wire bond according to an embodiment of the present disclosure; 
         FIG. 14  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 15  is a cross sectional view taken along an F-F′ direction of  FIG. 14 ; 
         FIG. 16  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure; 
         FIG. 17  is a partial cross sectional view of an antenna device according to an embodiment of the present disclosure; 
         FIG. 18  is a structural diagram of another antenna device according to an embodiment of the present disclosure; and 
         FIG. 19  is a cross sectional view taken along a G-G′ direction of  FIG. 18 . 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure will be further described in detail in conjunction with the drawings and embodiments below. It should be understood that the specific embodiments described herein are merely used for explaining the present disclosure and are not intended to limit the present disclosure. It should also be noted that, for ease of description, only part, but not all, of the structures related to the present disclosure are shown in the drawings. 
       FIG. 1  is a structural diagram of an antenna device according to an embodiment of the present disclosure, and  FIG. 2  is a cross sectional view taken along an A-A′ direction of  FIG. 1 . As shown in  FIG. 1  and  FIG. 2 , the antenna device provided in the embodiment of the present disclosure includes an antenna unit  10 , the antenna unit  10  includes a first substrate  11  and a second substrate  12  disposed opposite to each other, a region where the first substrate  11  and the second substrate  12  overlap forms a phase shift region  13  in a thickness direction of the first substrate  11 , the second substrate  12  includes a first step  14  protruding from the phase shift region  13  in a first direction X, a side of the first step  14  close to the first substrate  11  is provided with multiple first pads  15  arranged in a second direction Y, the first pads  15  are disposed on a side of the second substrate  12  close to the first substrate  11 , and the first direction X intersects the second direction Y. The antenna device further includes first connection lines  16 , the first pads  15  are connected to the first connection lines  16 , and the first pads  15  receive a drive signal output by an external driver circuit through the first connection lines  16 . 
     The antenna device may include one antenna unit  10  or may include multiple antenna units  10 , and  FIG. 1  is only an example of the antenna device including one antenna unit  10 , which may be set by those skilled in the art according to actual requirements. 
     With continued reference to  FIGS. 1 and 2 , the antenna unit  10  includes the first substrate  11  and the second substrate  12  disposed opposite to each other, the region where the first substrate  11  and the second substrate  12  overlap forms the phase shift region  13 , and the phase shift region  13  may adjust a phase of a radio frequency signal. Specifically, a drive signal is accessed to the phase shift region  13  to adjust the phase of the radio frequency signal according to the drive signal, a phase adjusted in a phase shift process of the radio frequency signal may be controlled by controlling the drive signal, and finally, it is achieved that the beam direction of the radio frequency signal transmitted by the antenna unit  10  is controlled, and the beam scanning is achieved. 
     With continued reference to  FIGS. 1 and 2 , the second substrate  12  includes the first step  14  protruding from the phase shift region  13  in the first direction X, the first step  14  is configured to dispose the first pads  15 , the first pad  15  is connected to the first connection line  16 , to receive a drive signal output by the external driver circuit through the first connection line  16 . The first pads are disposed on the first step  14  protruding from the phase shift region  13 , so that when the first pads  15  are connected to the first connection lines  16 , it will not be limited by the space of the first substrate  11 , which facilitates the connection between the first pad  15  and the first connection line  16 . Meanwhile, the first pads  15  are arranged in the second direction Y intersecting the first direction X, which is conducive to reducing the width of the first step  14 . 
     It should be noted that an included angle between the first direction X and the second direction Y may be set according to actual requirements, for example, the first direction X may be disposed to be perpendicular to the second direction Y as shown in  FIG. 1 , but which is not limited thereto. 
     Furthermore, the first pads  15  receive the drive signal output by the external driver circuit through the first connection lines  16 , to connect the drive signal to the first step  14  of the second substrate  12 , and the drive signal may be connected to the phase shift region  13  from the first step  14  through manners such as wiring or disposing a conductive structure on the second substrate  12 , thereby achieving the adjustment of the phase of the radio frequency signal. 
       FIG. 3  is a structural diagram of an antenna device in the related art, and  FIG. 4  is a cross sectional view taken along a B-B′ direction of  FIG. 3 . As shown in  FIG. 3  and  FIG. 4 , if the first pads  15  are directly bound to a flexible printed circuit (FPC)  17  to receive a drive signal output by an external driver circuit through the flexible printed circuit  17 , then the first pad  15  is required to have larger size to ensure the firmness of binding between the first pad  15  and the flexible printed circuit  17 , thereby achieving the reliable transmission of the drive signal. At this point, the first step  14  needs to be set wider to provide setting space for the first pads  15 . The inventor finds that if the first pads  15  are directly bound to the flexible printed circuit  17 , then the width of the first step  14  needs to be set to 1.4 mm or above, so that the requirements for binding and supporting the flexible printed circuit  17  may be satisfied. 
     In this embodiment, with continued reference to  FIGS. 1 and 2 , the first pad  15  receives the drive signal output by the external driver circuit through the first connection line  16  instead of being directly bound to the flexible printed circuit  17 , so that the size of the first pad  15  can be reduced while the connection firmness and the transmission reliability of the drive signal are ensured, and the width of the first step  14  can be reduced, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     In conclusion, according to the antenna device provided in the embodiment of the present disclosure, the first step  14  protruding from the phase shift region  13  is disposed on the second substrate  12 , and the first pads  15  are disposed on the first step  14 , which is conducive to receiving a drive signal required for performing a phase shift on a radio frequency signal. Meanwhile, the first pads  15  are connected to the first connection lines  16  to receive the drive signal output by the external driver circuit through the first connection lines  16 , so that the size of the first pad  15  can be reduced while the connection firmness and the transmission reliability of the drive signal are ensured, and the width of the first step  14  can be reduced, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     With continued reference to  FIGS. 1 and 2 , optionally, the length of the first pad  15  in the first direction X is D1, and D1≤100 μm. 
     As shown in  FIGS. 1 and 2 , the first pads  15  are connected to the first connection lines  16  to receive the drive signal output by the external driver circuit through the first connection lines  16 , so that the length D1 of the first pad  15  in the first direction X can be reduced to 100 μm while the transmission reliability of the drive signal is ensured, and the width of the first step  14  can be reduced, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     It should be noted that a value of the length D1 of the first pad  15  in the first direction X may be set according to actual requirements, for example, D1=40 μm, but which is not limited thereto. The value of the length D1 of the first pad  15  in the first direction X is not limited in the embodiments of the present disclosure. 
     Further, the first pad  15  receives the drive signal output by the external driver circuit through the first connection line  16  instead of being directly bound to the flexible printed circuit  17 , so that the size of the first pad  15  can be reduced and there is no need to provide a wider first step  14  to support the flexible printed circuit  17 , which is conducive to reducing the size of the whole antenna device and achieving the miniaturized application of the antenna device. 
     Optionally, the length of the first step  14  in the first direction X is D2, and D2≤0.2 mm. 
     As shown in  FIGS. 1 and 2 , the length D2 of the first step  14  in the first direction X may be reduced to within 0.2 mm due to the reduction in the size of the first pad  15 , which contributes to a reduction in the size of the whole antenna device while providing sufficient setting space for the first pads  15 , and thus the miniaturization application of the antenna device is achieved. 
     It should be noted that a value of the length D1 of the first pad  15  in the first direction X may be set according to actual requirements, which is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 1 and 2 , optionally, the antenna device provided in the embodiment of the present disclosure further includes multiple binding terminals  18 , each of the multiple binding terminals  18  is connected to a respective one of the first connection lines  16 , and the binding terminals  18  are configured to be connected to the external driver circuit. 
     Exemplarily, as shown in  FIGS. 1 and 2 , the binding terminals  18  are configured to be connected to the external driver circuit to receive the drive signal provided by the external driver circuit. 
     Exemplarily, as shown in  FIGS. 1 and 2 , the external driver circuit may be disposed on other main boards, the binding terminals  18  may be in binding connection with the flexible printed circuit  17 , the flexible printed circuit  17  is further provided with connection binding terminals  19 , and the connection binding terminals  19  are electrically connected to binding connection points between the flexible printed circuit  17  and the binding terminals  18 . The connection binding terminals  19  are configured to be in binding connection with the external driver circuit, thereby achieving an electrical connection between the external driver circuit and the binding terminals  18 . 
     In another embodiment, the external circuit may be directly disposed on the flexible printed circuit  17 , and the binding terminals  18  are in binding connection with the flexible printed circuit  17 , so that the binding terminals  18  receive the drive signal provided by the external circuit through the flexible printed circuit  17 . 
     In another embodiment, the binding terminals  18  may also be directly connected to the external circuit to receive a drive voltage signal provided by the external circuit, which is not limited in the embodiments of the present disclosure. 
     Further, as shown in  FIGS. 1 and 2 , each of the first pads  15  is correspondingly connected to a respective one of the binding terminals  18  through a respective one of the first connection lines  16 , thereby achieving that the first pads  15  receive the drive signal output by the external driver circuit. 
     It should be noted that when the antenna device is used, the flexible printed circuit  17  may be bent to a side of the second substrate  12  away from the first substrate  11 , so that the influence of the flexible printed circuit  17  on the width of a frame of the antenna device can be avoided on the basis of narrowing the first step  14 , which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
       FIG. 5  is a structural diagram of another antenna device according to an embodiment of the present disclosure, and  FIG. 6  is a cross sectional view taken along a C-C′ direction of  FIG. 5 . As shown in  FIG. 5  and  FIG. 6 , optionally, the antenna device provided in the embodiment of the present disclosure includes multiple antenna units  10  arranged in an array to form an antenna unit array  20 . 
     Exemplarily, as shown in  FIG. 5  and  FIG. 6 , the antenna device provided in the embodiment of the present disclosure includes multiple antenna units  10 , and the multiple antenna units  10  are mutually spliced to form the antenna unit array  20 , so that the antenna device is not limited by wiring and yield, and the transceiving efficiency and gain of the antenna can be improved, thereby satisfying the requirement of high gain of the antenna device. 
     The number of antenna units  10  may be set according to actual requirements, for example, as shown in  FIG. 5 , it may be set that the antenna device includes four antenna units  10 . 
       FIG. 7  is a structural diagram of another antenna device according to an embodiment of the present disclosure. As shown in  FIG. 7 , the antenna device may include only two antenna units  10 , and in other embodiments, the antenna device may include more antenna units  10 , which are not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 5 to 7 , optionally, the antenna device provided in the embodiments of the present disclosure further includes a support substrate  21 , and the antenna units  10  are arranged on a side of the support substrate  21 . 
     Exemplarily, as shown in  FIGS. 5 to 7 , the support substrate  21  is disposed to support and fix the antenna units  10 , thereby ensuring the reliability of the antenna unit array  20 . 
     With continued reference to  FIGS. 5 to 7 , optionally, the support substrate  21  includes a second step  22 , the second step  22  is located outside a coverage region of a vertical projection of the antenna unit array  20  on a plane where the support substrate  21  is located, and the second step  22  is located at an edge of the antenna device, the multiple binding terminals  18  are disposed on the second step  22 , and the multiple binding terminals  18  and the antenna unit array  20  are disposed on a same side of the support substrate  21 . 
     Exemplarily, as shown in  FIGS. 5 to 7 , the second step  22  protruding from the antenna unit array  20  is disposed on the support substrate  21  in a direction parallel to a plane where the first substrate  11  is located, and the second step  22  is located at the edge of the antenna device, so that the binding terminals  18  are disposed on the second step  22 , the binding terminals  18  are configured to be in binding connection with the flexible printed circuit  17 , and the flexible printed circuit  17  is connected to the external driver circuit. Therefore, the access of the drive signal is achieved. The second step  22  protruding from the antenna unit array  20  is disposed on the edge of the antenna device, and the binding terminals  18  are disposed on the second step  22 , so that when the binding terminals  18  are bound to the flexible printed circuit  17 , it will not be limited by the space of the antenna unit array  20 , and the binding between the binding terminals  18  and the flexible printed circuit  17  is facilitated. 
     With continued reference to  FIGS. 5 to 7 , optionally, the antenna device provided in the embodiments of the present disclosure further includes multiple second pads  23 , the second pads  23  are disposed on the support substrate  21 , the second pads  23  and the antenna unit array  20  are disposed on a same side of the support substrate  21 , each of the second pads  23  is connected to a respective one of the first pads  15  through a respective one of the first connection lines  16 , and each of the binding terminals  18  is connected to a respective one of the second pads  23 . 
     As shown in  FIGS. 5 to 7 , the binding terminals  18  are disposed on the support substrate  21  and the second step  22  where the binding terminals  18  are located is located at the edge of the antenna device; on one hand, the binding terminals  18  and the first pads  15  are not disposed on a same substrate; and on the other hand, a distance between the binding terminals  18  and part of the first pads  15  is relatively long, so that it is difficult to directly connect the binding terminals  18  and the first pads  15 . 
     In this embodiment, the second pads  23  are disposed on the support substrate  21 , each of the binding terminals  18  is connected to a respective one of the second pads  23 , and each of the second pads  23  is connected to a respective one of the first pads  15  through a respective one of the first connection lines  16 , so that the second pads  23  play a role in transferring the drive signal, to introduce the drive signal to the first pads  15  on the second substrate  12  from the binding terminals  18  on the support substrate  21 . Therefore, the difficulty of the connection between the binding terminals  18  and the first pads  15  is reduced and the connection is easy to be implemented. 
     With continued reference to  FIGS. 5 to 7 , optionally, the second pads  23  may be connected to the binding terminals  18  through first signal transmission lines  44  disposed on the support substrate  21 , but which is not limited thereto. 
     With continued reference to  FIGS. 5 to 7 , optionally, the multiple antenna units  10  include a first antenna unit  24  and a second antenna unit  25  disposed adjacent to each other, and in the first direction X, the first antenna unit  24  is disposed on a side of the first step  14  of the second antenna unit  25  away from the phase shift region  13  of the second antenna unit  25 ; the first pad  15  disposed on the first step  14  of the second antenna unit  25  is a first connection pad  26 , and the second pad  23  correspondingly connected to the first connection pad  26  is disposed on a side of the first antenna unit  24  close to the second antenna unit  25 . 
     As shown in  FIGS. 5 to 7 , since the first pads  15  receive the drive signal output by the external driver circuit through the first connection lines  16  instead of being directly bound to the flexible printed circuit  17 , so that the size of the first pad  15  can be reduced, and thus the width of the first step  14  can be reduced. At this point, without the limitation of the flexible printed circuit  17 , the splicing may be performed on a side of the first step  14  of the antenna unit  10 , that is, the periphery of the antenna unit  10  and other antenna units  10  may be spliced, so that the splicing flexibility of the antenna units  10  is improved, which is conducive to achieving the antenna unit array  20  with large size. 
     Further, as shown in  FIGS. 5 to 7 , in this embodiment, the first connection pads  26  are disposed between the first antenna unit  24  and the second antenna unit  25  disposed adjacent to each other, so that the distance between the first connection pad  26  and the second pad  23  correspondingly connected to the first connection pad  26  is reduced, and thus the difficulty of connecting the first connection pad  26  and the second pad  23  through the first connection line  16  is reduced. 
     With continued reference to  FIGS. 1 and 2 , optionally, the antenna device provided in the embodiment of the present disclosure further includes a binding substrate  27 , and the binding terminals  18  are disposed on the binding substrate  27 . 
     Exemplarily, as shown in  FIGS. 1 and 2 , the binding substrate  27  is provided, and the binding substrate  27  is configured to dispose the binding terminals  18 , to provide support for the binding terminals  18  while facilitating binding of the binding terminals  18  to the flexible printed circuit  17 . 
     Further, when the antenna device is manufactured, the binding substrate  27  may be bent to a side of the second substrate  12  away from the first substrate  11 , so that the influence of the binding substrate  27  on the width of the frame of the antenna device can be avoided. 
       FIG. 8  is a structural diagram of another antenna device according to an embodiment of the present disclosure. As shown in  FIG. 8 , optionally, the binding terminals  18  are disposed on a side of the second substrate  12  away from the first substrate  11 . 
     Exemplarily, as shown in  FIG. 8 , the binding terminals  18  may also be disposed directly on the side of the second substrate  12  away from the first substrate  11 , so that the influence of the flexible printed circuit  17  on the width of the frame of the antenna device can be avoided. 
     It should be noted that the setting positions of the binding terminals  18  are not limited to the above-described embodiments, and the positions of the binding terminals  18  may be set according to actual requirements in practical applications, which is not limited in the embodiments of the present disclosure. 
       FIG. 9  is a partial structural diagram of an antenna device according to an embodiment of the present disclosure, and  FIG. 10  is a cross sectional view taken along a D-D′ direction of  FIG. 9 . As shown in  FIG. 9  and  FIG. 10 , optionally, the multiple antenna units  10  further includes a third antenna unit  28 , and the third antenna unit  28  is disposed at an edge of the antenna unit array  20 . The second substrate  12  of the third antenna unit  28  includes a third step  29  protruding from the phase shift region  13  of the third antenna unit  28 , the third step  29  is disposed at the edge of the antenna unit array  20 ; and the multiple binding terminals  18  are disposed on a side of the third step  29  close to the first substrate  11 . 
     Exemplarily, as shown in  FIGS. 9 and 10 , the third antenna unit  28  is disposed at the edge of the antenna unit array  20 , the second substrate  12  of the third antenna unit  28  is provided with the third step  29  protruding from the phase shift region  13  of the third antenna unit  28 , and the third step  29  is disposed at the edge of the antenna unit array  20 , so that the binding terminals  18  are disposed on the third step  29 . The binding terminals  18  are configured to be in binding connection with the flexible printed circuit  17 , and the flexible printed circuit  17  is connected to the external driver circuit, so that the access of drive signals is achieved. 
     At the edge of the antenna unit array  20 , the second substrate  12  of the third antenna unit  28  is provided with the third step  29  protruding from the phase shift region  13  of the third antenna unit  28 , and the binding terminals  18  are disposed on the third step  29 , so that when the binding terminals  18  are bound to the flexible printed circuit  17 , it will not be limited by the space of the phase shift region  13 , and the binding between the binding terminals  18  and the flexible printed circuit  17  is facilitated. 
     It should be noted that, as shown in  FIGS. 9 and 10 , since the binding terminals  18  are disposed on the second substrate  12  of the third antenna unit  28 , the drive signal on the binding terminals  18  may be directly introduced into the phase shift region  13 . Therefore, the first pads  15  may not be provided for the third antenna unit  28 , which is conducive to reducing the size of the third antenna unit  28  and achieving the miniaturization application of the antenna device. However, the present disclosure is not limited to this. 
     With continued reference to  FIGS. 9 and 10 , optionally, the multiple antenna units  10  include the first antenna unit  24  and the second antenna unit  25  disposed adjacent to each other, and the first antenna unit  24  is disposed on a side of the first step  14  of the second antenna unit  25  away from the phase shift region  13  of the second antenna unit  25 ; and the second substrate  24  of the first antenna unit  24  includes a fourth step  30  protruding from the phase shift region  13  of the first antenna unit  24 , and the fourth step  30  is disposed on a side of the first antenna unit  24  close to the second antenna unit  25 . The antenna device further includes multiple second pads  23 , each of the second pads  23  is connected to a respective one of the first pads  15  through a respective one of the first connection lines  16 , and each of the binding terminals  18  is connected to a respective one of the second pads  23 ; and the first pad  15  disposed on the first step  14  of the second antenna unit  25  is the first connection pad  26 , and the second pad correspondingly connected to the first connection pad  26  is disposed on a side of the fourth step  30  of the first antenna unit  24  close to the first substrate  11  of the first antenna unit  24 . 
     As shown in  FIG. 9  and  FIG. 10 , the first pads  15  receive the drive signal output by the external driver circuit through the first connection lines  16  instead of being directly bound to the flexible printed circuit  17 , so that the size of the first pad  15  can be reduced, and thus the width of the first step  14  can be reduced. At this point, without the limitation of the flexible printed circuit  17 , the splicing may be performed on a side of the first step  14  of the antenna unit  10 , that is, the periphery of the antenna unit  10  and other antenna units  10  may be spliced, so that the splicing flexibility of the antenna units  10  is improved, which is conducive to achieving the antenna unit array  20  with large size. 
     Further, as shown in  FIGS. 9 and 10 , the third step  29  where the binding terminals  18  are located is located at the edge of the antenna unit array  20 , so that a distance between the binding terminals  18  and part of the first pads  15  is relatively long, and thus it is difficult to directly connect the binding terminals  18  and the first pads  15 . 
     With continued reference to  FIGS. 9 and 10 , in this embodiment, the fourth step  30  protruding from the phase shift region  13  of the first antenna unit  24  is disposed on a side of the first antenna unit  24  close to the second antenna unit  25 , the second pads  23  correspondingly connected to the binding terminals  18  are disposed on the fourth step  30 , and the second pads  23  are correspondingly connected to the first pads  15  through the first connection lines  16 , so that the second pads  23  play a role in transferring the drive signal among the antenna units, to introduce the drive signal to the first pads  15  on the second substrate  12  of each antenna unit through the binding terminals  18 . Therefore, the difficulty of the connection between the binding terminals  18  and the first pads  15  is reduced and the connection is easy to be implemented. 
     Further, as shown in  FIGS. 9 and 10 , the fourth step  30  for disposing the second pads  23  is disposed on a side of the first antenna unit  24  close to the second antenna unit  25 , to reduce a distance between the first connection pad  26  and the second pad  23  correspondingly connected thereto, so that the difficulty of connecting the first connection pad  26  and the second pad  23  through the first connection line  16  is reduced. 
     With continued reference to  FIGS. 9 and 10 , optionally, the support substrate  21  is disposed to support and fix the antenna units  10 , so that the reliability of the antenna unit array  20  may be ensured. 
       FIG. 11  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure, and  FIG. 12  is a cross sectional view taken along an E-E′ direction of  FIG. 11 . As shown in  FIGS. 11 and 12 , since drive signals are all transmitted on the second substrates  12 , the second substrate  12  of the first antenna unit  24  and the second substrate  12  of the second antenna unit  25  may be set to the same substrate, to support and fix the antenna unit array  20  through the second substrate  12 . Therefore, the support substrate  21  may not be provided, which is conducive to reducing the thickness of the antenna device and achieving the light and thin application of the antenna device. 
     With continued reference to  FIGS. 9 to 12 , optionally, the second pad  23  may be connected to the binding terminal  18  through a second signal transmission line  45  disposed on the second substrate  12 , but which is not limited thereto. 
     With continued reference to  FIGS. 5 to 7  and  FIGS. 9 to 12 , optionally, the length of the second pad  23  in the first direction X is D4, and D4≤100 μm. 
     As shown in  FIGS. 5 to 7  and  FIGS. 9 to 12 , the second pads  23  are correspondingly connected to the first pads  15  through the first connection lines  16 , and the second pads  23  are correspondingly connected to the binding terminals  18  instead of being directly bound to the flexible printed circuit  17 , so that the length D4 of the second pad  23  in the first direction X may be reduced to 100 μm while the transmission reliability of the drive signal is ensured, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     It should be noted that a value of the length D4 of the second pad  23  in the first direction X may be set according to actual requirements, for example, D4=40 μm, but which is not limited thereto. The embodiments of the present disclosure do not limit this. 
     With continued reference to  FIGS. 9 to 12 , optionally, in the first direction X, the fourth step  30  has the length of D3, where D3≤0.2 mm. 
     As shown in  FIGS. 9 to 12 , the length D3 of the fourth step  30  in the first direction X may be reduced to within 0.2 mm due to the reduction in the size of the second pad  23 , which contributes to the reduction in the size of the whole antenna device while providing sufficient setting space for the second pads  23 , and thus the miniaturization application of the antenna device is achieved. 
     With continued reference to  FIGS. 5 to 7  and  FIGS. 9 to 12 , optionally, in a direction parallel to a plane where the support substrate  21  is located, the shortest distance between an edge of a side of the first connection pad  26  away from the second pad  23  corresponding to the first connection pad  26  and an edge of a side of the second pad  23  away from the first connection pad  26  corresponding to the second pad  23  is D5, and D5≤0.3 mm. 
     As shown in  FIGS. 5 to 7  and  FIGS. 9 to 12 , the shortest distance D5 between the edge of the side of the first connection pad  26  away from the second pad  23  corresponding to the first connection pad  26  and the edge of the side of the second pad  23  away from the first connection pad  26  corresponding to the second pad  23  satisfies a condition of D5≤0.3 mm, so that the second pad  23 , the first connection pad  26 , and the first connection line  16  for connecting the second pad  23  and the first connection pad  26  do not take up excessive space, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     Optionally, the first connection line  16  is made of at least one of gold, copper, aluminum or silver alloy. 
     The gold, copper, aluminum and silver alloy are good in conductivity, and the first connection line  16  is made of the above materials, so that the first connection line  16  has a small impedance, and the connection reliability of the first connection line  16  can be improved. 
     Exemplarily, the first connection line  16  may be a gold wire, and the gold wire has good conductivity and is not easy to break. 
     Meanwhile, the first connection line  16  is a gold wire and the connection may be performed through a wire bond process. The wire bond process is a manner of a circuit connection in an integrated circuit (IC) package. The second pad  23  and the first pad  15  are connected through the wire bond process, so that the size of the second pad  23  and the size of the first pad  15  can be further reduced (for example, to 40 μm) while the connection firmness and the transmission reliability of the drive signal are ensured, and thus the size of the step can be reduced, which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
       FIG. 13  is a structural diagram of a wire bond according to an embodiment of the present disclosure. As shown in  FIG. 13 , exemplarily, when the wire bond process is used for connecting the second pad  23  and the first pad  15 , a gold wire  32  may penetrate out through a hollow clamp  31 ; the extended part of the gold wire  32  is melted through the arcing and becomes spherical under the action of a surface tension; a ball is then bonded to one of the first pad  15  and the second pad  23  by the hollow clamp  31 , after which a spherical pad is formed; a bent gold wire  32  is drawn out of the spherical pad and then bonded to the other one of the first pad  15  and the second pad  23  to form a flat pad; and the gold wire  32  is broken to form the first connection line  16 . 
     It should be noted that the material and the connection process of the first connection line  16  are not limited to the embodiments described above, and those skilled in the art may select the material and the connection process of the first connection line  16  according to actual requirements, which is not limited in the embodiments of the present disclosure. 
     Optionally, after the first pad  15  is connected to the second pad  23  through the first connection line  16 , the first pad  15 , the first connection line  16  and the second pad  23  may be packaged through packaging materials such as UV glue or epoxy glue, so that the first pad  15 , the first connection line  16  and the second pad  23  are protected, and the transmission reliability of the drive signal between the first pad  15  and the second pad  23  is further improved. 
       FIG. 14  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure, and  FIG. 15  is a cross sectional view taken along an F-F′ direction of  FIG. 14 . Optionally, the antenna unit  10  further includes multiple third pads  33  disposed on a side of the second substrate  12  away from the first pad  15 , and the third pads  33  are correspondingly connected to the first pads  15  through the first connection lines  16 . The antenna device further includes multiple second pads  23 , the second pads  23  are arranged on a side of the support substrate  21  close to the antenna unit array  20 , the second pads  23  are correspondingly connected to the third pads  33 , and the binding terminals  18  are correspondingly connected to the second pads  23 . 
     Exemplarily, as shown in  FIGS. 14 and 15 , the second pads  23  correspondingly connected to the binding terminals  18  are disposed on a side of the support substrate  21  close to the antenna unit array  20 , the third pads  33  are disposed on a side of the second substrate  12  away from the first pads  15 , and the second pads  23  are correspondingly connected to the third pads  33 , so that a drive signal on the binding terminals  18  is connected to a side of the second substrate  12  away from the first pads  15 , and the third pads  33  are correspondingly connected to the first pads  15  through the first connection lines  16 . Therefore, the drive signal is introduced into the phase shift region  13 , to achieve the adjustment of a phase of a radio frequency signal. 
     The third pads  33  are disposed on a side of the second substrate  12  away from the first pads  15 , and the second pads  23  and the third pads  33  are connected on a side of the second substrate  12  away from the first pads  15 , so that the influence of the second pads  23  on the size of the antenna device can be avoided, the size of the whole antenna device may be reduced, and thus the miniaturization application of the antenna device is achieved. 
     With continued reference to  FIGS. 14 and 15 , optionally, an edge side wall of the first step  14  is provided with multiple grooves  34 , the multiple grooves  34  are disposed corresponding to the multiple first pads  15 , and the first connection line  16  is a conductive layer covering an inner wall of the groove  34 . 
     Exemplarily, as shown in  FIGS. 14 and 15 , the grooves  34  are disposed on the edge side wall of the first step  14 , a metallization process is performed on the grooves  34  to prepare conductive layers on the inner walls of the grooves  34 , so that the first connection lines  16  are formed. The first pad  15  is connected to the third pad  33  through the first connection line  16 , so that the drive signal is introduced from the side of the second substrate  12  away from the first pads  15 . 
     The metallization process of the groove  34  may be set according to actual requirements. For example, the groove  34  is first formed on the edge side wall of the first step  14  in a manner of laser or grinding, and then a conductive layer is formed on an inner wall of the groove  34  in a manner of deposition or electroplating to form the first connection line  16 , which is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 14 and 15 , optionally, a vertical projection of the groove  34  on a plane where the first substrate  11  is located includes a semicircle or a polygon. 
     Exemplarily, as shown in  FIG. 14 , the grooves  34  may be semi-circular, which is simple in process and easy to be implemented. 
       FIG. 16  is a partial structural diagram of another antenna device according to an embodiment of the present disclosure. As shown in  FIG. 16 , the grooves  34  may be set to be rectangular, and in other embodiments, the grooves  34  may also be configured to be any other shape, which is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 14 to 16 , optionally, the second pad may be connected to the binding terminal  18  through a third signal transmission line  46  disposed on the support substrate  21 , but which is not limited thereto. 
     It should be noted that the first signal transmission lines  44 , the second signal transmission lines  45 , or the third signal transmission lines  46  in the above embodiments may be located in a same film layer, but which are not limited thereto. When the number of antenna units  10  in the antenna unit array  20  is relatively large, the first signal transmission lines  44 , the second signal transmission lines  45 , or the third signal transmission lines  46  may be disposed in multiple film layers, and different film layers are isolated by insulating layers, so that transmission lines in the different film layers may overlap in the thickness direction of the first substrate  11 , and the influence of excessive transmission lines on the size of the antenna device is reduced. 
     With continued reference to  FIG. 15 , optionally, the second pad  23  is in contact connection with the third pad  33  corresponding to the second pad  23 . 
     Exemplarily, as shown in  FIG. 15 , the second pad  23  is in direct contact connection with the third pad  33  corresponding to the second pad  23 , so that no other connection structure is needed, which is conducive to reducing the thickness of the antenna device and achieving the light and thin application of the antenna device. 
       FIG. 17  is a partial cross sectional view of an antenna device according to an embodiment of the present disclosure. As shown in  FIG. 17 , optionally, the antenna device provided in the embodiment of the present disclosure further includes conductive connection structures  35 , and each of the conductive connection structures  35  is connected to a respective second pad of the second pads  23  and a respective third pad of the third pads  33  that corresponds to the respective second pad, respectively. 
     The second substrate  12  and/or the support substrate  21  may have a problem of uneven surface so that there may be a gap between the second pad  23  and the third pad  33  corresponding thereto, causing that the second pad  23  and the third pad  33  cannot be contacted. In this embodiment, as shown in  FIG. 17 , the conductive connection structure  35  with a certain thickness is provided to connect the second pad  23  and the third pad  33 , so that a connection between the second pad  23  and the third pad  33  can be secured, and the reliability of the antenna device can be improved. 
     It should be noted that the specific structure of the conductive connection structure  35  may be set according to actual requirements as long as the connection between the second pad  23  and the third pad  33  is ensured. 
     For example, the conductive connection structure  35  may be a pin, where the pin is a pin-shaped metal structure with or without elasticity, and the connection can be more reliable by connecting the pin between the second pad  23  and the third pad  33 . 
     The material of the conductive connection structure  35  may be set according to actual requirements. For example, the material of the conductive connection structure  35  includes copper and/or gold, to ensure the conductive performance of the conductive connection structure  35 . For example, the conductive connection structure  35  is a structure with gold plated on the outer side of the copper material, so that the cost can be reduced while the conductive performance of the conductive connection structure  35  is ensured. 
     Moreover, in the thickness direction of the first substrate  11 , the length of the conductive connection structure  35  may be set according to actual requirements, for example, the length of the conductive connection structure  35  is 1 mm to 10 mm, but which is not limited thereto. 
       FIG. 18  is a structural diagram of another antenna device according to an embodiment of the present disclosure, and  FIG. 19  is a cross sectional view taken along a G-G′ direction of  FIG. 18 . As shown in  FIGS. 18 and 19 , optionally, the antenna device provided in the embodiment of the present disclosure further includes multiple binding terminals  18 , the binding terminals  18  are correspondingly connected to the first connection lines  16 , the binding terminals  18  are disposed on a flexible printed circuit  17 , and the flexible printed circuit  17  is connected to an external driver circuit. 
     Exemplarily, as shown in  FIGS. 18 and 19 , multiple binding terminals  18  are disposed on the flexible printed circuit  17 , and the first connection lines  16  are directly connected to the binding terminals  18  on the flexible printed circuit  17  to enable the transmission of drive signals between the first pads  15  and the binding terminals  18 . Further, the flexible printed circuit  17  is further provided with connection binding terminals  19 , the connection binding terminals  19  are electrically connected to the binding terminals  18 , and the connection binding terminals  19  are configured to be in binding connection with the external driver circuit, so that an electric connection between the external driver circuit and the binding terminals  18  is achieved. 
     When the antenna device is used, the flexible printed circuit  17  may be bent to a side of the second substrate  12  away from the first substrate  11 , so that the influence of the flexible printed circuit  17  on the width of the frame of the antenna device can be avoided on the basis of narrowing the first step  14 , which is conducive to reducing the size of the whole antenna device and achieving the miniaturization application of the antenna device. 
     With continued reference to  FIGS. 6, 10, 15 and 17 , optionally, the antenna device provided in the embodiment of the present disclosure further includes an adhesive layer  36  disposed between the second substrate  12  of the antenna unit  10  and the support substrate  21 . 
     In this embodiment, the adhesive layer  36  disposed between the second substrate  12  and the support substrate  21  is provided to fix the antenna unit  10  on the support substrate  21 , so that the reliability of the antenna device is ensured. 
     As shown in  FIGS. 6 and 10 , the adhesive layer  36  may be provided on the second substrate  12  in an entire layer to improve the adhesion firmness between the antenna unit  10  and the support substrate  21 . 
     In other embodiments, as shown in  FIGS. 15 and 17 , the adhesive layer  36  may also be disposed partially on the second substrate  12 , so that the influence of the adhesive layer  36  on the connection between the second pad  23  and the third pad  33  can be avoided. This may be set by those skilled in the art according to actual requirements. 
     It should be noted that the material of the adhesive layer  36  may be set according to actual requirements, for example, the adhesive layer  36  may be made of a frame adhesive, an encapsulation adhesive, an optical adhesive, or the like, which is not limited in the embodiments of the present disclosure. 
     In other embodiments, the second substrate  12  and the support substrate  21  may be directly physically connected. For example, the second substrate  12  and the support substrate  21  may be directly physically connected by using a snap-fit structure, to avoid the influence of the adhesive layer  36  on the radio frequency signal. This is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, the antenna unit  10  further includes multiple phase shift units  37 , the multiple phase shift units  37  are arranged in an array in the phase shift region  13 , and the phase shift units  37  are configured to adjust a phase of a radio frequency signal. In the antenna device, a gap distance between adjacent phase shift units  37  is equal. 
     Exemplarily, as shown in  FIGS. 1 to 19 , the antenna unit  10  includes multiple phase shift units  37  arranged in an array, the phase shift units  37  are configured to adjust the phase of the radio frequency signal to achieve the control of the beam direction of the radio frequency signal transmitted by the antenna unit  10  and thus achieve the beam scanning. 
     As shown in  FIGS. 1 to 12  and  FIGS. 14 to 19 , in the antenna device, by setting the gap distance between any adjacent phase shift units  37  being equal, the antenna pattern side lobe can be slight, and the scanning performance of the antenna device can be ensured. 
     With continued reference to  FIGS. 5, 7, 9, 11 and 14 , when the antenna device includes multiple antenna units  10 , since the first pads  15  receive the drive signals output by the external driver circuit through the first connection lines  16  instead of being directly bound to the flexible printed circuit  17 , the size of the first pad  15  can be reduced while the connection firmness and transmission reliability of the drive signals are ensured, and thus the width of the first step  14  can be reduced. 
     At this point, without the limitation of the flexible printed circuit  17 , the splicing may be performed on a side of the first step  14  of the antenna unit  10 , that is, the periphery of the antenna unit  10  and other antenna units  10  may be spliced, so that the splicing flexibility of the antenna units  10  is improved, which is conducive to achieving the antenna unit array  20  with large size. 
     Meanwhile, the reduction in the width of the first step  14  can ensure that the gap distance between the phase shift units  37  in the adjacent antenna units  10  is not increased, thereby ensuring the scanning performance of the antenna device. 
     The gap distance between adjacent phase shift units  37  may be set according to actual requirements. For example, the gap distance between adjacent phase shift units  37  is ½ to 1 times of the operating wavelength, which is not limited in the embodiment of the present disclosure. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, the phase shift unit  37  includes a microstrip line  38 , a ground metal layer  39  and a liquid crystal layer  40 . The microstrip line  38  is disposed on a side of the second substrate  12  close to the first substrate  11 , the ground metal layer  39  is disposed on a side of the first substrate  11  close to the second substrate  12 , and the liquid crystal layer  40  is disposed between the first substrate  11  and the second substrate  12 . The antenna unit  10  further includes a radiation electrode  41  and a feed network  42 , the radiation electrode  41  is disposed on a side of the first substrate  11  away from the second substrate  12 , and the feed network  42  is in coupling connection with the microstrip line  38 . 
     Exemplarily, as shown in  FIGS. 1 to 12  and  FIGS. 14 to 19 , the phase shift unit  37  includes the liquid crystal layer  40  disposed between the first substrate  11  and the second substrate  12 , the microstrip line  38  is disposed on a side of the liquid crystal layer  40  away from the first substrate  11 , and the ground metal layer  39  is disposed on a side of the liquid crystal layer  40  away from the second substrate  12  An electric field is formed between the microstrip line  38  and the ground metal layer  39  by applying drive signals to the microstrip line  38  and the ground metal layer  39 , respectively, and the electric field may drive liquid crystal molecules  401  in the liquid crystal layer  40  to deflect, thereby changing a dielectric constant of the liquid crystal layer  40 . The microstrip line  38  is further configured to transmit a radio frequency signal, the radio frequency signal is transmitted in the liquid crystal layer  40  between the microstrip line  38  and the ground metal layer  39 , and due to a change of a dielectric constant of the liquid crystal layer  40 , the radio frequency signal transmitted on the microstrip line  38  is phase-shifted, so that a phase of the radio frequency signal is changed, and the phase shift function of the radio frequency signal is achieved. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, a radiation electrode  41  is further disposed on a side of the first substrate  11  away from the second substrate  12 , and a perpendicular projection of the ground metal layer  39  on the first substrate  11  at least partially overlaps a perpendicular projection of the radiation electrode  41  on the first substrate  11 . The ground metal layer  39  is provided with a first hollow portion  391 , the vertical projection of the radiation electrode  41  on a plane where the ground metal layer  39  is located covers the first hollow portion  391 , a vertical projection of the microstrip line  38  on the plane where the ground metal layer  39  is located covers the first hollow portion  391 , the radio frequency signal is transmitted between the microstrip line  38  and the ground metal layer  39 , the liquid crystal layer  40  between the microstrip line  38  and the ground metal layer  39  shifts the phase of the radio frequency signal to change the phase of the radio frequency signal, and the radio frequency signal after the phase shift is coupled to the radiation electrode  41  at the first hollow portion  391  of the ground metal layer  39 , so that the radiation electrode  41  radiates the signal outwards. 
     It should be noted that the radiation electrodes  41  are disposed corresponding to the microstrip lines  38 . For example, the radiation electrodes  41  are in one-to-one correspondence with the microstrip lines  38 , and the radiation electrodes  41  corresponding to different microstrip lines  38  are insulated from each other. Optionally, different drive signals are applied to different microstrip lines  38 , so that liquid crystal molecules at positions corresponding to different microstrip lines  38  are deflected differently, and the dielectric constants of the liquid crystal layer  40  at the positions are different, to adjust phases of radio frequency signals at different positions of the microstrip lines  38 . Finally, different beam directions of the radio frequency signals are achieved. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, the feed network  42  is disposed on a side of the first substrate  11  away from the second substrate  12 , the feed network  42  is coupled to the microstrip lines  38 , and the feed network  42  is configured to transmit a radio frequency signal to each microstrip line  38 , where the feed network  42  may be distributed in a tree shape and includes multiple branches, and one branch provides a radio frequency signal for one microstrip line  38 . The ground metal layer  39  includes a second hollow portion  392 , a vertical projection of the feed network  42  on the first substrate  11  covers a vertical projection of the second hollow portion  392  on the first substrate  11 , the radio frequency signal transmitted by the feed network  42  is coupled to the microstrip line  38  at the second hollow portion  392  of the ground metal layer  39 , and the dielectric constant of the liquid crystal layer  40  is changed by controlling the deflection of liquid crystal molecules  401  in the liquid crystal layer  40 , so that the phase shift of the radio frequency signal on the microstrip line  38  is achieved. 
     In other embodiments, the feed network  42  may also be disposed on the same layer as the microstrip line  38 , and the feed network  42  is coupled to the microstrip line  38 , which may be set by those skilled in the art according to actual requirements, and is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, the first pad  15  is connected to the microstrip line  38  through a drive signal line  43  to provide a drive signal for the microstrip line  38 , and different drive signals are applied to different microstrip lines  38 , so that liquid crystal molecules at positions corresponding to different microstrip lines  38  are deflected differently, and dielectric constants of the liquid crystal layer  40  at the positions are different, to adjust phases of radio frequency signals at different positions of the microstrip lines  38 . Finally, different beam directions of the radio frequency signals are achieved. 
     In other embodiments, the first pad  15  may also be connected to the ground metal layer  39  through a conductive structure to provide a ground signal for the microstrip line  38 , which may be set by those skilled in the art according to practical requirements and is not limited in the embodiments of the present disclosure. 
     With continued reference to  FIGS. 1 to 12  and  FIGS. 14 to 19 , optionally, the antenna device provided in the embodiments of the present disclosure further includes a support structure  47 , where the support structure  47  is configured to support the first substrate  11  and the second substrate  12  to provide a containment space for the liquid crystal layer  40 . 
     Optionally, materials of the first substrate  11 , the second substrate  12  and the support substrate  21  may be set according to actual requirements. For example, the first substrate  11 , the second substrate  12  and the support substrate  21  may be made of glass, a printed circuit board (PCB) material or the like, which is not limited in the embodiments of the present disclosure. 
     Optionally, materials of the microstrip line  38 , the ground metal layer  39 , the radiation electrode  41  and the feed network  42  may be set according to actual requirements. For example, the microstrip line  38  and the ground metal layer  39  may be made of gold or copper, which is not specifically limited in the embodiments of the present disclosure. 
     Optionally, materials of the first pad  15 , the second pad  23 , and the third pad  33  may be set according to actual requirements. For example, the first pad  15 , the second pad  23 , and the third pad  33  may be made of indium tin oxide (ITO) or copper (Cu) so that the first pad  15 , the second pad  23 , and the third pad  33  are difficult to be oxidized. The materials are not limited in the embodiments of the present disclosure. 
     It should be noted that the above are merely preferred embodiments of the present disclosure and the technical principles applied herein. It should be understood by those skilled in the art that the present disclosure is not limited to the particular embodiments described herein. For those skilled in the art, various apparent modifications, adaptations, combinations and substitutions may be made without departing from the scope of the present disclosure. Therefore, although the present disclosure has been described in detail through the above embodiments, the present disclosure is not limited to the above embodiments and may include more other equivalent embodiments without departing from the concept of the present disclosure. The scope of the present disclosure is determined by the scope of the appended claims.