Flexible film antenna and unmanned aerial vehicle carrying flexible film antennaTechnical Field
The application relates to the field of radio communication, and particularly discloses a flexible film antenna and an unmanned aerial vehicle carrying the same.
Background
In recent years, along with the rapid development of unmanned aerial vehicle technology, unmanned aerial vehicles of different types and purposes are endlessly layered, and under the scene of long-time navigation at high altitude, fixed wing unmanned aerial vehicles play an increasingly important role in civil and military fields due to the advantages of high flying height, long endurance time and low flying cost. In the practical application process, in order to reduce the weight of the whole fixed-wing unmanned aerial vehicle and improve the load ratio of the unmanned aerial vehicle, a new film material is needed to replace the traditional metal material to be used as the skin material of the unmanned aerial vehicle wing.
In addition, in the related radio communication field of unmanned aerial vehicle, the VHF frequency band (frequency interval is 135 MHz-185 MHz) is widely used in ground military and civil communication systems, but because the working frequency band of the VHF frequency band is lower, the wavelength is longer, the required radio antenna is oversized and overweight, and the fixed wing unmanned aerial vehicle is not suitable for being installed and used, so that the high-altitude communication of the fixed wing unmanned aerial vehicle cannot be carried out by using the relatively mature VHF frequency band.
Disclosure of Invention
Aiming at the problem in the prior art that how to reduce the weight of the unmanned aerial vehicle and enable the fixed wing unmanned aerial vehicle to apply a communication system related to a VHF frequency band, the application provides a flexible film antenna and an unmanned aerial vehicle carrying the flexible film antenna. Specifically, a first aspect of the present application provides a flexible film antenna, including:
the flexible film radiation layer is provided with a first copper foil layer with a specific shape on a first surface of the flexible film radiation layer and is used for radiating corresponding preset radio frequency signals;
the flexible film reflecting layer is symmetrically arranged with the flexible film radiating layer and is arranged at the position opposite to the radiating direction of the flexible film radiating layer;
a second copper foil layer is arranged on one surface of the flexible film reflecting layer.
In a possible implementation of the first aspect, the base layers of the flexible thin film radiation layer and the flexible thin film reflection layer are polyimide films;
the thickness of the polyimide film is in the interval [0.25mm,0.5mm ].
In one possible implementation manner of the first aspect, the preset radio frequency signal is a VHF band radio frequency signal;
the frequency of the preset radio frequency signal is in the interval [135MHz,185MHz ].
In a possible implementation of the first aspect, the flexible thin film radiation layer includes:
a base layer made of polyimide film material;
the first copper foil layer is arranged on the first surface of the base layer, a radiation gap with a specific shape is arranged in the first copper foil layer, and the radiation gap comprises a closed shape formed by one or more of a spiral line segment, a circular line segment and a rectangular line segment and is used for radiating corresponding preset radio frequency signals;
the second surface of the base layer is provided with a microstrip feeder corresponding to the radiation slot, and a preset radio frequency signal is radiated or received through the radiation slot;
one end of the microstrip feeder is free, and the other end is connected with the high-frequency connector through the high-frequency cable.
In a possible implementation of the first aspect, the radiation frequency range of the flexible film antenna is tunable in the VHF band;
one or more of a spiral line segment, a circular line segment and a rectangular line segment in the radiation slit are adjusted to realize the adjustment of the shape of the radiation slit:
the radiation frequency range of the flexible film antenna is adjusted by adjusting the shape of the radiation slot.
In one possible implementation of the first aspect described above, the microstrip feed line includes a rectangular copper foil;
the electrical performance of the flexible film antenna is adjusted by adjusting the side length of the rectangular copper foil and the position of the rectangular copper foil.
In a possible implementation of the first aspect, the high frequency connector is an SMA type connector or an SSMA type connector.
In a possible implementation of the above first aspect, the spacing between the flexible thin film radiation layer and the flexible thin film reflective layer is in the interval [0.1λ,0.5λ ];
wherein lambda is the wavelength corresponding to the preset radio frequency signal.
In one possible implementation of the first aspect, the second copper foil layer is a full-coverage copper foil layer or a mesh-structure copper foil layer;
the mesh spacing of the mesh-structure copper foil layer is not more than 100mm.
A second aspect of the present application provides an unmanned aerial vehicle, on the wing of which any one of the flexible film antennas provided in the first aspect is mounted;
the unmanned aerial vehicle receives and transmits preset radio frequency signals through the flexible film antenna.
Compared with the prior art, the application has the following beneficial effects:
according to the technical scheme provided by the application, the polyimide film is used as the base material to manufacture the flexible film antenna, and the flexible film antenna can plan and cover the required preset frequency (especially VHF frequency band) through the radiation gap of the radiation layer.
Drawings
Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:
fig. 1 is a schematic structural view of a first side of a flexible film radiation layer in a flexible film antenna according to an embodiment of the present application.
Fig. 2 is a schematic structural view of a second side of a flexible film radiation layer in a flexible film antenna according to an embodiment of the present application.
Fig. 3 is a schematic structural view of a flexible film reflecting layer in a flexible film antenna according to an embodiment of the present application.
Fig. 4 is a schematic structural view of a flexible film antenna disposed on a wing of a unmanned aerial vehicle according to an embodiment of the present application.
Detailed Description
The present application will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present application, but are not intended to limit the application in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present application.
In order to solve the problem that a new film material is needed to replace the traditional metal material to be used as the skin material of the unmanned aerial vehicle wing in the prior art, in some embodiments of the application, in order to reduce the weight of the whole unmanned aerial vehicle with the fixed wing and improve the loading ratio of the unmanned aerial vehicle with the fixed wing, the skin material of the wing can be changed from the metal material into a polyimide film material. On the basis, in order to introduce the relatively mature VHF frequency band into the high-altitude communication of the fixed-wing unmanned aerial vehicle, in some embodiments of the application, a polyimide film can be used for developing a corresponding flexible film antenna, and the original polyimide film skin on the wing of the fixed-wing unmanned aerial vehicle is replaced in situ under the condition of not increasing the weight and the volume, so that the application of the VHF frequency band radio frequency signal receiving and transmitting function in the high-altitude communication of the fixed-wing unmanned aerial vehicle is realized. The flexible film antenna developed by using the polyimide film and the carrying arrangement of the flexible film antenna on the unmanned aerial vehicle are specifically explained and described below with reference to specific embodiments.
In the foregoing embodiments, the present application provides a flexible film antenna and an unmanned aerial vehicle with the flexible film antenna. Fig. 1 to 3 show schematic structural views of a flexible film antenna, as shown in fig. 1 to 3, which may specifically include:
the flexible thin film radiation layer 100, a first copper foil layer 101 with a specific shape is disposed on a first surface of the flexible thin film radiation layer 100, for radiating a corresponding preset radio frequency signal. In the above embodiment of the present application, the preset rf signal is a VHF band rf signal, that is, the frequency of the preset rf signal is in the interval [135mhz,185mhz ]. Those skilled in the art may select a desired frequency range of the preset radio frequency signal according to actual needs, which is not limited herein.
The flexible thin film reflection layer 200, the flexible thin film reflection layer 200 is symmetrically arranged with the flexible thin film radiation layer 100 and is disposed at a position opposite to the radiation direction of the flexible thin film radiation layer 100; a second copper foil layer 201 is provided on one side of the flexible thin film reflective layer 200.
In the above embodiment, the flexible thin film radiation layer 100 and the flexible thin film reflection layer 200 have the radiation layer base layer 102 and the reflection layer base layer 202, respectively, and the radiation layer base layer 102 and the reflection layer base layer 202 are polyimide films, and the thickness is in the interval of 0.25mm and 0.5 mm. It can be understood that, because the wing skin material of the fixed wing unmanned aerial vehicle is changed from a metal material into a polyimide film material, the flexible film antenna provided by the application can adopt the same polyimide film material as a base layer of the antenna, so that the flexible film antenna can be directly applied to the wing part of the fixed wing unmanned aerial vehicle.
In the above embodiment, as shown in fig. 1 to 2, it may be understood that, for the flexible film radiation layer 100, it may specifically include: a base layer 102 made of polyimide film material; the first copper foil layer 101 is arranged on the first surface of the base layer 102, a radiation gap 103 with a specific shape is arranged in the first copper foil layer 101, and the radiation gap 103 comprises a closed shape formed by one or more of a spiral line segment, a circular line segment and a rectangular line segment and is used for radiating corresponding preset radio frequency signals. In the above embodiment of the present application, the preset radio frequency signal is in VHF band, and the corresponding radiation slot 103 may be formed by connecting straight line/curve segments such as a spiral segment a, a circular segment b, a spiral segment c, and a rectangular segment d, and by adjusting one or more of these straight line/curve segments, the shape of the radiation slot 103 can be adjusted, and further by adjusting the shape of the radiation slot 103, the radiation frequency range of the flexible film antenna can be adjusted.
As shown in fig. 1 to 2, the second surface of the base layer 102 is provided with a microstrip feed line 104 corresponding to the radiation slot 103, and the radiation slot 103 radiates or receives a preset radio frequency signal, and one end of the microstrip feed line 104 is free, and the other end is connected to a high frequency connector 106 through a high frequency cable 105. The microstrip feed line 104 may be specifically a rectangular copper foil, and the electrical performance of the flexible film antenna may be adjusted by adjusting the length and width of the rectangular copper foil and the position of the rectangular copper foil; the high-frequency cable 105 can be preferably a high-frequency cable with small diameter, soft texture and low loss so as to reduce the influence of the weight of the cable on the film, and a flexible high-frequency cable with the diameter of 1.8mm can be preferably selected; the high frequency connector 106 may be selected from SMA type connectors or SSMA type connectors. The specific components required may be selected by those skilled in the art according to actual needs, and are not limited herein.
In the above embodiment, specifically, the distance between the flexible thin film radiation layer 100 and the flexible thin film reflection layer 200 is set in the interval [0.1λ,0.5λ ], where λ is the wavelength corresponding to the preset radio frequency signal.
In the above embodiment, specifically, the second copper foil layer 201 may be a fully covered copper foil layer as shown in fig. 3, or may be a mesh-structure copper foil layer, where in the case where the second copper foil layer 201 is of a mesh structure, in order to ensure that the reflection characteristic can be achieved, the mesh pitch of the mesh-structure copper foil layer is not more than 100mm.
In some embodiments of the present application, there is also provided an unmanned aerial vehicle on which the flexible film antenna provided in the foregoing embodiments is mounted. Specifically, fig. 4 shows a schematic structural diagram of a flexible film antenna disposed on an unmanned aerial vehicle wing 300, where it can be seen that the flexible film radiation layer 100 is disposed on a lower surface of the unmanned aerial vehicle wing 300, and the flexible film reflection layer 200 is disposed on an upper surface of the unmanned aerial vehicle wing 300. The flexible film antenna provided by the application can directly replace a polyimide film adopted by the surface skin of the wing of the fixed wing unmanned aerial vehicle, and can realize the signal wireless radio frequency function of the unmanned aerial vehicle on specific frequency bands such as VHF and the like without increasing the weight of the unmanned aerial vehicle and affecting the aerodynamic characteristics of the unmanned aerial vehicle, thereby having popularization value.
In summary, according to the technical scheme provided by the application, the polyimide film is adopted as the base material to manufacture the flexible film antenna, and the flexible film antenna can plan and cover the required preset frequency (especially VHF frequency band) through the radiation gap of the radiation layer, compared with the existing antenna module, the flexible film antenna has the advantages of small size, light weight, foldable storage, curved surface installation and simple and firm structure, and can be conformally installed on the wing of the fixed-wing unmanned aerial vehicle under the condition that the aerodynamic characteristics of the unmanned aerial vehicle are not influenced, so that the function of transmitting and receiving the radio frequency signals of the specific frequency band of the fixed-wing unmanned aerial vehicle is increased, and the fixed-wing unmanned aerial vehicle can utilize the mature VHF frequency band to carry out high-altitude communication, so that the flexible film antenna has popularization value.
The foregoing describes specific embodiments of the present application. It is to be understood that the application is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the application. The embodiments of the application and the features of the embodiments may be combined with each other arbitrarily without conflict.