Antenna unit supporting dual-frequency satellite communication, antenna assembly and terminal equipment

Abstract

The invention discloses an antenna unit supporting dual-frequency satellite communication, an antenna assembly and terminal equipment, and relates to the technical field of satellite communication. According to the technical key points, through the design of a top-layer metal ring structure and two bottom-layer dipole metal branches, a single feed unit can cover S-band satellite communication uplink and downlink bands divided by the international telecommunications alliance and expand C-band satellite communication at the same time, and the size of the antenna is smaller, so that the antenna is particularly suitable for miniaturized terminal equipment. The problem that the performance and the size of an existing antenna do not meet the application requirements of terminal equipment is solved.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and in particular, to an antenna unit, an antenna assembly, and a terminal device supporting dual-band satellite communication. Background Art

[0002] In terminal satellite communication technology, it is necessary to design an antenna with good performance to meet the requirements in terms of connectivity, stability, and data transmission rate. Satellite communication technology usually operates in the S band (2 - 4 GHz) and the extended C band (3 - 8 GHz). The S band has a longer wavelength, making it difficult to achieve a relatively wide bandwidth, and the size of the antenna operating in the S band will be relatively large, not meeting the size requirements of terminal devices. At the same time, due to the large distance between frequency bands, a dual-band coverage method needs to be adopted, which increases the design difficulty.

[0003] In the patent document with the publication number CN116053760A, part of the adjacent frame of the device is used as a radiator, and by single-point feeding, the antenna shows left-handed circular polarization and right-handed circular polarization in the first frequency band and the second frequency band respectively, achieving dual-band coverage and miniaturization of the terminal device. However, this antenna design uses the floor of the terminal itself to achieve good radiation of the surrounding branches, and the distance between the branches and the floor is fixed, which is not suitable for terminals that need to communicate with multiple satellites, and terminals with large differences in multiple frequency band coverage and requiring replacement of communication antennas. In the patent document with the publication number CN220209268U, the high-frequency grounding substrate and the low-frequency radiation substrate are shared. At the same time, the low elevation non-circularity value of the antenna is relatively small, balancing the satellite receiving ability and manufacturing cost of the antenna, but the area is 200×200 square millimeters, which is still too large for handheld terminal devices. In the patent document with the publication number CN118040296A, the antenna size is reduced by setting LC matching circuits at each feeding port of the four-arm spiral antenna, but it can only cover one operating frequency band and cannot achieve the two-way satellite communication function that requires simultaneous transmission and reception.

[0004] Therefore, in terminal devices, there is still a lack of an antenna design with dual-band coverage, good satellite receiving performance, and miniaturization. Summary of the Invention

[0005] The present invention provides an antenna unit, an antenna assembly, and a terminal device supporting dual-band satellite communication to solve the problem that the performance and size of existing antennas do not meet the application requirements of terminal devices.

[0006] The present invention is achieved through the following technical solutions:

[0007] In the first aspect of the present invention, an antenna unit supporting dual-band satellite communication is provided, including:

[0008] A rectangular metal ring located on the top layer of the antenna unit;

[0009] A dipole structure layer, located below the metal ring; the dipole structure layer is formed by two L-shaped metal strips with different lengths and different orientations, and the two L-shaped metal strips and the rectangular metal ring form a radiator;

[0010] A dielectric layer, located between the rectangular metal ring and the dipole structure layer, and connecting the rectangular metal ring and the dipole structure layer;

[0011] A feeding point, arranged on one of the L-shaped metal strips, to feed the radiator through the feeding point, so as to make the radiator exhibit left-handed circular polarization in both the first frequency band and the second frequency band.

[0012] The antenna unit of the present invention adopts the design of a top-layer metal ring structure and two bottom-layer dipole metal branches, realizing the function of a single feeding unit covering two frequency bands at the same time, making the antenna smaller in size, and thus particularly suitable for miniaturized terminal devices. Since there are two mutually orthogonal modes in the rectangular metal ring structure, good left-handed circular polarization performance can be achieved in the first working frequency band through feeding excitation. Since the feeding point is arranged on one of the L-shaped metal strips, it has a delayed excitation effect on the other L-shaped metal strip, and couples the excitation electric field of the rectangular metal ring to achieve good left-handed circular polarization performance in the second working frequency band, and at the same time has a non-low left-handed circular polarization gain, meeting the dual-frequency coverage of the S band and the extended C band, supporting dual-frequency satellite communication, and can be applied to scenarios where communication with multiple satellites is required or multiple frequency bands with large differences need to be covered.

[0013] As a preferred embodiment, when the antenna unit works, one of the L-shaped metal strips is excited by the feeding point to generate a first longitudinal current, and the other L-shaped metal strip is excited with a delay to generate a first transverse current, and the rectangular metal ring is excited by the metal strip to generate a second transverse current and a second longitudinal current;

[0014] The coupling of the second transverse current and the second longitudinal current makes the radiator achieve left-handed circular polarization in the first frequency band;

[0015] The first longitudinal current is combined with the second transverse current and the second longitudinal current to form a first current, the first transverse current is combined with the second transverse current and the second longitudinal current to form a second current, and the coupling of the first current and the second current makes the radiator achieve left-handed circular polarization in the second frequency band.

[0016] As a preferred embodiment, the frequency of the first frequency band is lower than the frequency of the second frequency band.

[0017] As a preferred embodiment, the first frequency band is the S band, and the second frequency band is the extended C band.

[0018] As a preferred embodiment, the antenna unit further includes a feeding unit for feeding the radiator through the feeding point.

[0019] As a preferred embodiment, the feeding unit includes a metal conductive inner core, an insulating sleeve, an outer conductor, and a protective sleeve that are coaxially arranged from the inside to the outside in sequence; the metal conductive inner core is connected to the feeding point on one of the L-shaped metal strips, the outer conductor is connected to the other L-shaped metal strip, and the metal conductive inner core is coaxially arranged with one side of the other L-shaped metal strip.

[0020] As a preferred embodiment, the dielectric layer is made of a composite ceramic material.

[0021] In a second aspect of the present invention, there is provided an antenna assembly, including: a housing, an analog metal ground plane, and the antenna unit for supporting dual-band satellite communication according to any one of the first aspects of the present invention; the antenna unit and the analog metal ground plane are arranged inside the housing.

[0022] As a preferred embodiment, the antenna assembly further includes a battery arranged inside the housing.

[0023] In a third aspect of the present invention, there is provided a terminal device, including the antenna unit for supporting dual-band satellite communication according to any one of the first aspects of the present invention or the antenna assembly according to any one of the second aspects of the present invention.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] It covers the uplink and downlink frequency bands of satellite communication in the S band and the extended C band divided by the International Telecommunication Union, can be used in satellite phone terminals, and supports dual-band satellite communication;

[0026] By adopting the design of the top-layer metal ring structure and the two bottom-layer metal branches, the function of simultaneously covering two frequency bands with a single feeding unit is realized, making the antenna smaller in size, and it can be as small as 38×20×6 cubic millimeters;

[0027] Good circular polarization performance is achieved in both the first frequency band and the second frequency band, and at the same time, it has a non-low left-handed circular polarization gain, meeting the communication stability requirements of satellite phones, improving the energy conversion efficiency, and reducing the device power consumption;

[0028] The antenna design is flexible, does not rely on the main board of the terminal for radiation, and is more in line with the application requirements of plug-and-play antennas in this project in practice;

[0029] The antenna assembly is independent of other components in the terminal, is very suitable for terminals that need to communicate with multiple satellites, and facilitates the replacement of the antenna unit and thus the change of communication frequency bands. Description of the Drawings

[0030] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings. In the drawings:

[0031] Figure 1 is a schematic diagram of a satellite phone terminal and its antenna in use;

[0032] Figure 2 is a schematic diagram of the application scenario of an antenna unit and an antenna assembly according to an embodiment of the present invention;

[0033] Figure 3 is a schematic diagram of the structure of an antenna unit according to an embodiment of the present invention;

[0034] Figure 4 is a top view of an antenna unit according to an embodiment of the present invention;

[0035] Figure 5 is a bottom view of an antenna unit according to an embodiment of the present invention;

[0036] Figure 6 is a schematic diagram of the current distribution of an antenna unit in the first frequency band according to an embodiment of the present invention;

[0037] Figure 7 is a schematic diagram of the current distribution of an antenna unit in the second frequency band according to an embodiment of the present invention;

[0038] Figure 8 is a simulation result diagram of the current distribution of an antenna unit in the first frequency band according to an embodiment of the present invention;

[0039] Figure 9 is a simulation result diagram of the current distribution of an antenna unit in the second frequency band according to an embodiment of the present invention;

[0040] Figure 10 is a simulation result diagram of the S-parameters and axial ratio of an antenna unit in the first frequency band according to an embodiment of the present invention;

[0041] Figure 11 is a simulation result diagram of the S-parameters and axial ratio of an antenna unit in the second frequency band according to an embodiment of the present invention;

[0042] Figure 12 is a 3D pattern of the left-handed circular polarization gain of an antenna unit in the first frequency band at the uplink frequency band of 2000 MHz according to an embodiment of the present invention;

[0043] Figure 13 It is the left - hand circular polarization gain 3D pattern of an antenna unit according to an embodiment of the present invention at 2180 MHz in the downlink frequency band of the first frequency band;

[0044] Figure 14 It is the left - hand circular polarization gain 3D pattern of an antenna unit according to an embodiment of the present invention at 3550 MHz in the downlink frequency band of the first frequency band;

[0045] Figure 15 It is the simulation result diagram of the curve of the minimum gain of an antenna unit according to an embodiment of the present invention changing with frequency in the first frequency band;

[0046] Figure 16 It is the simulation result diagram of the curve of the minimum gain of an antenna unit according to an embodiment of the present invention changing with frequency in the second frequency band;

[0047] Figure 17 It is the axial ratio pattern of an antenna unit according to an embodiment of the present invention at 2050 MHz in the first frequency band;

[0048] Figure 18 It is the axial ratio pattern of an antenna unit according to an embodiment of the present invention at 3550 MHz in the second frequency band;

[0049] Figure 19 It is the structural schematic diagram of a feeding unit according to an embodiment of the present invention;

[0050] Figure 20 It is the structural schematic diagram of an antenna assembly according to an embodiment of the present invention. Detailed implementation manners

[0051] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in combination with embodiments and the accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and do not limit the present invention.

[0052] It should be noted that the terms "including" and "having" in the description and claims of the present invention and any variations thereof are intended to cover non - exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily be limited to other steps or units inherent to the device.

[0053] The terms used in the various embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the various embodiments of the present invention. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the present invention pertain. The terms (such as those defined in a general use dictionary) will be interpreted to have the same meaning as the contextual meaning in the relevant technical field and will not be interpreted to have an idealized meaning or an overly formal meaning, unless clearly defined in the various embodiments of the present invention.

[0054] In the embodiments of the present invention, specific technical terms are used to describe some technical features, and the meanings of the relevant technical terms are explained as follows.

[0055] 1. Antenna: A device that transmits or receives energy in communication. The antenna transforms the guided wave propagating on the transmission line into an electromagnetic wave propagating in free space, or vice versa.

[0056] 2. Wavelength: Generally refers to the wavelength corresponding to the center frequency point of the operating frequency band of the antenna. The wavelength of the radiated signal in air can be calculated from the speed of light and the signal frequency. Specifically, the air wavelength = speed of light * frequency, where the speed of light is taken as 3×10 8 m / s and the frequency is taken as MHz. This calculation will change in a medium, and the medium wavelength = speed of light / (λ × frequency), where λ is the relative permittivity.

[0057] 3. Axial ratio (AR) of the antenna: In circular polarization, the trajectory traced by the end point of the electric field vector in space is elliptical periodically. The ratio of the major axis to the minor axis of the ellipse is called the axial ratio. The axial ratio is an important performance index of a circularly polarized antenna. It represents the purity of circular polarization and is an important index for measuring the difference in signal gain of the whole machine in different directions. The closer the circular polarization axial ratio value of the antenna is to 1 (the trajectory traced by the end point of the electric field vector in space is circular), the better its circular polarization performance.

[0058] 4. Antenna radiation pattern: Refers to the graph of the relative field strength radiated by the antenna varying with the angle at a certain distance far from the antenna. Generally, it is characterized by two mutually perpendicular antenna patterns.

[0059] 5. Coupling: can be understood as direct coupling and / or indirect coupling. "Coupled connection" can be understood as direct coupling connection and / or indirect coupling connection. Direct coupling can also be called "electrical connection", which is understood as the physical contact and electrical conduction between components; it can also be understood as the connection between different components in the circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals; "indirect coupling" can be understood as two conductors being electrically conductive in an airless / non-contact manner. Indirect coupling can also be called capacitive coupling, for example, signal transmission is achieved by coupling between the gap between two conductive parts to form an equivalent capacitor.

[0060] 6. Communication frequency band / working frequency band: No matter what type of antenna, it always works within a certain frequency range (frequency band width).

[0061] 7. Resonance / resonance frequency: refers to the frequency at which the imaginary part of the antenna input impedance is zero, also called the resonant frequency. The resonant frequency can have a frequency range, that is, the frequency range in which resonance occurs.

[0062] 8. Resonance frequency band: The range of resonant frequencies. The return loss characteristic of any frequency point within the resonant frequency band can be less than -10dB.

[0063] 9. Polarization direction of the antenna: At a given point in space, the electric field strength E (vector) is a function of time t. As time goes by, the endpoints of the vector periodically draw a trajectory in space; if the trajectory is a straight line and perpendicular to the ground, it is called vertical polarization. If it is horizontal to the ground, it is called horizontal polarization. If the trajectory is an ellipse or a circle, when observed along the propagation direction, it rotates in the right hand or clockwise direction with time, which is called right-hand circular polarization (RHCP). If it rotates in the left hand or counterclockwise direction with time, it is called left-hand circular polarization (LHCP).

[0064] Since linearly polarized waves will undergo polarization rotation when passing through the ionosphere, and circularly polarized waves can resist the above rotation due to their rotational symmetry, circularly polarized antennas are generally used as transmitting or receiving antennas in satellite navigation or communication. At the same time, in satellite navigation or communication systems, if a traditional linearly polarized antenna is used to receive circularly polarized waves sent by a satellite antenna, or if a traditional linearly polarized antenna is used to send energy to a satellite antenna that receives circularly polarized signals, half of the energy will be lost in both cases due to polarization mismatch. Moreover, circularly polarized antennas are insensitive to the orientation of the transmitting and receiving antennas. In addition, circularly polarized antennas can also reduce the impact of multipath effects on signals and improve signal stability and reliability.

[0065] Figure 1Shown is a schematic diagram of a common satellite phone terminal and its antenna. For satellite phones, an external circularly polarized antenna is usually adopted. Generally speaking, the external circularly polarized antenna is a four-arm helix antenna, which is composed of four helical arms printed on the outer wall of a dielectric cylinder. A feeding network is used to feed the four helical arms, and the feeding phase differences of the four feeding ports port1 to port4 are 0°, 90°, 180°, and 270° in sequence, which can realize a wide-beam circularly polarized radiation pattern. However, the four-arm helix antenna is limited by the covered frequency band, and other circularly polarized antennas also have problems such as too large size, being not suitable for terminals that need to communicate with multiple satellites, covering multiple frequency bands with large differences, and requiring replacement of communication antennas.

[0066] The present invention designs an antenna unit supporting dual-band satellite communication for terminal equipment satellite communication, an antenna assembly including the antenna unit, and a terminal device, as Figure 2 Shown is a schematic diagram of the application scenarios of the antenna unit and the antenna assembly of the present invention. The antenna unit satisfies dual-band coverage of the S band and the extended C band, realizes good communication between the terminal device and the satellite, and also meets the requirement of replacing different antennas for different satellites and frequency bands in the scenario of multi-satellite multi-band satellite phones.

[0067] In a first aspect, an embodiment of the present invention provides an antenna unit supporting dual-band satellite communication, as Figures 3 - 5 Shown is a schematic diagram of the structure of the antenna unit. The antenna unit mainly consists of a rectangular metal ring on the top layer, a dipole structure layer on the bottom layer, and a dielectric layer in the middle. The dielectric layer is located between the metal ring and the dipole structure layer and connects the metal ring and the dipole structure layer.

[0068] Among them, the dielectric layer can adopt a printed circuit board (PCB). The rectangular metal ring on the top layer is formed on the upper surface of the PCB board through the PCB printing process, and the dipole structure layer on the bottom layer is formed on the lower surface of the PCB board through the PCB printing process. The rectangular metal ring and the dipole structure layer are not connected to each other.

[0069] The printed circuit board (PCB) can adopt a flame-retardant material (FR-4) dielectric board, or a Rogers dielectric board, or a hybrid dielectric board of Rogers and FR-4, etc. FR-4 is a code for a flame-retardant material grade, and the Rogers dielectric board is a high-frequency board.

[0070] The dipole structure layer is formed by two L-shaped metal strips with different lengths and different orientations. The two L-shaped metal strips and the metal ring form a radiator. And a feeding point is arranged on one of the L-shaped metal strips (the first metal strip), and the feeding unit of the antenna performs single-point feeding through this feeding point.

[0071] As Figure 4 、5 As shown, the fold angle of another L-shaped metal strip (the second strip) faces opposite to that of the first metal strip, with a spacing therebetween, forming a dipole structure at the bottom. The second metal strip is at a certain distance from the feeding point on the first metal strip, such that the second metal strip is excited with a delay. The top-layer rectangular metal loop is excited with a delay by the first metal strip and the second metal strip, so that the radiator can simultaneously excite two electric fields in the vertical direction within the first frequency band and the second frequency band, making the polarization mode of the antenna element circular polarization within the first frequency band and the second frequency band.

[0072] The working mode of the antenna element of the present invention is as follows:

[0073] Within the first frequency band, two modes can be excited in the top-layer rectangular metal loop. Figure 6 Shown is a schematic diagram of the current distribution of the antenna element within the first frequency band, which are respectively the transverse (x-direction) mode and the longitudinal (y-direction) mode of the loop antenna.

[0074] Within the second frequency band, due to a certain distance between the transverse part of the second metal strip and the first feeding point (the longitudinal part of the first metal strip), the second metal strip is excited with a delay. The transverse length of the second metal strip of the second metal strip is appropriate, and there is an appropriate phase delay between the transverse part and the first feeding point, which can provide a transverse (x-direction) mode within the second frequency band, and the longitudinal part of the first metal strip provides a longitudinal (y-direction) mode within the second frequency band, as Figure 7 Shown is a schematic diagram of the current distribution of the antenna element within the second frequency band. The simulation results of the current distribution of the antenna element within the first frequency band and the second frequency band are respectively referred to Figure 8 、 Figure 9 as shown.

[0075] Therefore, when the antenna element works, the first metal strip is first excited by the feeding point to generate a first longitudinal current (y-direction), the second metal strip is excited with a delay to generate a first transverse current (x-direction), and the rectangular metal loop is excited by the L-shaped metal strip to generate a second transverse current (x-direction) and a second longitudinal current (y-direction).

[0076] The coupling of the second transverse current and the second longitudinal current enables the radiator to achieve left-handed circular polarization within the first frequency band; while the first longitudinal current is combined with the second transverse current and the second longitudinal current to form a first current, and the first transverse current is combined with the second transverse current and the second longitudinal current to form a second current. Between the two mode resonance frequency bands, a coupling of the first current and the second current with the same amplitude and a 90° phase difference is formed, enabling the radiator to achieve left-handed circular polarization within the second frequency band.

[0077] The upper and lower layers of the antenna element respectively excite circular polarization in two frequency bands, and the circular polarization rotation directions are the same, enabling the antenna element of the present invention to be applied to satellite communication terminals.

[0078] In some embodiments, the frequency of the first frequency band is lower than that of the second frequency band. Further, the first frequency band is the S band, and the second frequency band is the extended C band.

[0079] Figure 10 It is the simulation result diagram of the S parameter and axial ratio of the antenna unit of the present invention in the first frequency band. At 2050 MHz in the first frequency band, two orthogonal modes are excited in the rectangular metal ring by the second metal strip at the bottom layer. By observing the S parameter curve, it can be found that there are two resonance points. The low-frequency resonance point corresponds to the transverse mode (x direction), and the high-frequency resonance point corresponds to the longitudinal mode (y direction). Between the resonance frequency bands of the two modes, the amplitudes of the two orthogonal modes required for circular polarization are the same and have a 90° phase difference, making the antenna unit exhibit left-handed circular polarization at 2050 MHz in the first frequency band.

[0080] Figure 11 It is the simulation result diagram of the S parameter and axial ratio of the antenna unit of the present invention in the second frequency band. At 3550 MHz in the second frequency band, the rectangular metal ring provides transverse and longitudinal currents, and the first metal strip at the bottom layer provides the longitudinal mode (y direction). The two are combined to form the first current; when a quarter of a cycle has passed, the second metal strip at the bottom layer provides the transverse current, and the current provided by the rectangular metal ring is combined to form the second current. The first current and the second current have a 90° phase difference and are orthogonal in direction. The rotation direction is counterclockwise when observed from the radiation direction, which can make the antenna unit exhibit left-handed circular polarization at 3550 MHz in the second frequency band.

[0081] Figure 12 It is the 3D pattern of the left-handed circular polarization gain of the antenna unit of the present invention at 2000 MHz in the uplink frequency band of the first frequency band. Figure 13 It is the 3D pattern of the left-handed circular polarization gain of the antenna unit of the present invention at 2180 MHz in the downlink frequency band of the first frequency band. Figure 14 It is the 3D pattern of the left-handed circular polarization gain of the antenna unit of the present invention at 3550 MHz in the downlink frequency band of the first frequency band. It can be seen that the radiator can simultaneously excite two electric fields in the vertical direction at certain frequencies in the first frequency band and the second frequency band, making the polarization mode of the antenna unit exhibit left-handed circular polarization in both the first frequency band and the second frequency band.

[0082] The antenna unit can utilize the design of the top-layer metal ring structure and the bottom-layer dipole structure to exhibit left-handed circular polarization in the first frequency band and the second frequency band, and the left-handed circular polarization gain is greater than -4 dBic.

[0083] Figure 15 It is the simulation result diagram of the curve of the minimum gain of the antenna unit of the present invention changing with frequency in the first frequency band. Figure 16It is a simulation result diagram of the curve of the minimum gain of the antenna unit of the present invention varying with frequency in the second frequency band. In the figure, the left-handed circular polarization gains of the antenna unit in the first frequency band and in the second frequency band are higher than -4dBi within the range of 0°≤θ≤10°, and the radiation beams generated within this range can enable the satellite phone terminal to have good performance in satellite communication.

[0084] Figure 17 It is the axial ratio pattern of the antenna unit of the present invention at 2050 MHz in the first frequency band, Figure 18 and it is the axial ratio pattern of the antenna unit of the present invention at 3550 MHz in the second frequency band. In the figure, the axial ratio pattern generated by the antenna unit at 2050 MHz satisfies the axial ratio requirement for circular polarization (axial ratio < 5dB) on the spherical surface in the z direction within the range of 0°≤θ≤10°, and the antenna exhibits circular polarization characteristics; the axial ratio pattern generated by the antenna unit at 3550 MHz satisfies the axial ratio requirement for circular polarization (axial ratio < 5dB) on the spherical surface in the z direction within the range of 0°≤θ≤10°, and the antenna exhibits circular polarization characteristics. Among them, θ is the angle formed with the z axis in the xoy plane, and φ is the angle formed with the x axis in the xoy plane.

[0085] The circular polarization axial ratio of the antenna is less than or equal to 5dB in some frequency bands of the first frequency band, and the circular polarization axial ratio of the antenna is less than or equal to 5dB in some frequency bands of the second frequency band. When the circular polarization axial ratio of the antenna is less than or equal to 5dB, it can be considered that the antenna has good circular polarization characteristics. If taking S 11 <-10dB as the boundary, the operating frequency band of the antenna unit can include 1958 MHz to 2214 MHz, and 3384 MHz to 3898 MHz.

[0086] According to the division of the International Telecommunication Union, the first frequency band in the embodiments of the present invention can include the receiving and transmitting (up and down link) frequency bands (1980 MHz to 2010 MHz and 2170 MHz to 2200 MHz) of the S-band satellite mobile service divided by the International Telecommunication Union, and the second frequency band can include the transmitting frequency band (3400 MHz to 3700 MHz) of the extended C-band satellite mobile service divided by the International Telecommunication Union.

[0087] Therefore, the antenna unit of the present invention can achieve the coverage of the up and down link frequency bands of the S-band satellite communication and the extended C-band satellite communication divided by the International Telecommunication Union, and can be extended to other frequency bands through design to meet the requirements of different types of dual-frequency communication.

[0088] The antenna unit of the present invention adopts a top-layer metal ring structure and a design of two metal branches at the bottom layer, realizing the function of a single-feed unit covering two frequency bands, making the antenna smaller in size. Since the rectangular metal ring structure has two mutually orthogonal modes and can be excited by feeding, circular polarization performance is achieved in the first operating frequency band. Due to the phase difference caused by coupling between the feeding point and the other radiator, there is a phase difference between the radiator directly connected to the feeding point, and good circular polarization performance is achieved in the second operating frequency band. At the same time, it has a not-low left-handed circular polarization gain, meeting the communication stability requirements of satellite phones, improving the energy conversion efficiency, and reducing the power consumption of the device.

[0089] In the design and implementation of the antenna unit, the dipole structure layer at the bottom layer is connected to the antenna main board, which can improve the stability of the antenna performance.

[0090] In terms of occupied space, a rectangular ring with a perimeter of about λ g = 110 mm is used as the generation of the resonance point of the first frequency band, so that the overall size of the antenna unit can be designed as 38×20×6 cubic millimeters; in terms of covered frequency bands, by coupling the top-layer rectangular metal ring with the bottom-layer L-shaped metal strip, the S-band satellite communication transceiver frequency band coverage is achieved, and at the same time, the top-layer rectangular metal ring radiates at the second frequency band to achieve the extended C-band satellite communication transceiver frequency band coverage. And the antenna design is flexible, does not rely on the main board of the terminal for radiation, and is more in line with the plug-and-play application requirements of the antenna in this project in practice.

[0091] In some embodiments, the antenna unit further includes a feeding unit, and the feeding unit is used to feed the radiator through the feeding point.

[0092] As a preferred embodiment, the feeding unit (coaxial cable) includes a metal conductive inner core (inner conductor), an insulating sleeve, an outer conductor, and a protective sleeve coaxially arranged from the inside to the outside in sequence. As Figure 19 shown in the structure schematic diagram of the feeding unit, the outer conductor is a metal skin and is coaxially arranged with the metal conductive inner core. The insulating sleeve is arranged between the metal conductive inner core and the outer conductor, wrapping the metal conductive inner core, and the protective sleeve is arranged on the outer surface of the outer conductor, wrapping the outer conductor.

[0093] Combined with Figure 3 shown, the metal conductive inner core (inner conductor) is connected to the feeding point on one of the L-shaped metal strips (the first metal strip) to feed the radiator through the feeding point. The outer conductor is connected to the other L-shaped metal strip (the second metal strip). And the feeding unit is coaxially arranged with one side of the second metal strip, without additionally increasing the occupied area of the antenna unit. When coaxial feeding, the conductive inner core is connected to the radiator part of the antenna, and the outer conductor is generally grounded.

[0094] As a preferred embodiment, the dielectric layer is made of a composite ceramic material. The size can be designed as a rectangular body with a height of 6 mm, a length of 38 mm, and a width of 20 mm, and the dielectric constant is 3.

[0095] In some embodiments, the dielectric layer has through mounting holes to facilitate the installation of the antenna unit.

[0096] In a second aspect, an embodiment of the present invention further provides an antenna assembly.

[0097] Figure 20 The following is a schematic structural diagram of an antenna assembly of the present invention. The antenna assembly includes: a housing, an analog metal ground plane, and the antenna unit supporting dual-band satellite communication described in the first aspect of the present invention. The antenna unit and the analog metal ground plane are both disposed inside the housing.

[0098] This antenna assembly is designed with a relatively large analog metal ground plane placed at the bottom end of the antenna, which can reduce the influence of other components of the terminal. At the same time, the antenna unit is independent of other components in the terminal, and is very suitable for terminals that need to communicate with multiple satellites, facilitating the replacement of the antenna unit and thus the change of communication frequency bands.

[0099] The housing, the antenna unit, and the analog metal ground plane have mounting holes, which can be threaded holes. The antenna unit and the analog metal ground plane are fixed inside the plastic housing of the terminal by screws. It should be understood that in some embodiments, the housing, the mounting holes, etc. do not necessarily present the state shown in the figure, as long as they can all play the role of fixing the antenna assembly and the antenna unit.

[0100] In some embodiments, the antenna unit is located at the front edge inside the housing, thereby providing a reasonable layout space for the terminal device.

[0101] In some embodiments, the housing can be plastic or glass, and can also be replaced with other materials, such as polyethylene terephthalate (PET).

[0102] In some embodiments, the antenna assembly further includes a battery, and the battery is disposed inside the housing. Preferably, the battery can be disposed between the antenna unit and the bottom end of the plastic housing.

[0103] In a third aspect, an embodiment of the present invention further provides a terminal device, including the antenna unit supporting dual-band satellite communication described in the first aspect of the present invention or the antenna assembly described in the second aspect. Among them, the terminal device can be an electronic device such as a mobile phone, a tablet computer, or a smart wearable device.

[0104] Since the antenna unit of the present invention can be 38×20×6 cubic millimeters, greatly reducing the size, compared with the existing terminal antenna design, the technical solution of this scheme is closer to the engineering application of satellite communication phone terminals. The present invention greatly compresses the space occupied by the antenna unit, improving the portability and aesthetics of satellite phone terminals.

[0105] The specific embodiments described above have further elaborated on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An antenna unit supporting dual-frequency satellite communications, characterized in that: include: A rectangular metal ring located on the top layer of the antenna element; A dipole structure layer is located below the metal ring; the dipole structure layer is formed by two L-shaped metal strips of different lengths and directions, and the two L-shaped metal strips and the rectangular metal ring form a radiator; A dielectric layer is located between the rectangular metal ring and the dipole structure layer, and connects the rectangular metal ring and the dipole structure layer; A feeding point is arranged on one of the L-shaped metal strips to feed the radiator through the feeding point, so that the radiator presents left-hand circular polarization in both the first frequency band and the second frequency band.

2. The antenna unit supporting dual-frequency satellite communication according to claim 1, characterized in that: When the antenna unit is working, one of the L-shaped metal strips is excited by the feeding point to generate a first longitudinal current, the other L-shaped metal strip is excited by a delay to generate a first transverse current, and the rectangular metal ring is excited by the metal strips to generate a second transverse current and a second longitudinal current; The second transverse current and the second longitudinal current are coupled so that the radiator realizes left-hand circular polarization in the first frequency band; The first longitudinal current, the second transverse current and the second longitudinal current are combined into a first current, the first transverse current, the second transverse current and the second longitudinal current are combined into a second current, and the first current and the second current are coupled so that the radiator realizes left-hand circular polarization in the second frequency band.

3. The antenna unit supporting dual-frequency satellite communication according to claim 2, characterized in that: The frequency of the first frequency band is lower than the frequency of the second frequency band.

4. The antenna unit supporting dual-frequency satellite communication according to claim 3, characterized in that: The first frequency band is an S frequency band, and the second frequency band is an extended C frequency band.

5. The antenna unit supporting dual-frequency satellite communication according to claim 1, characterized in that: The antenna unit further includes a feeding unit, and the feeding unit is used to feed the radiator through the feeding point.

6. The antenna unit supporting dual-frequency satellite communication according to claim 5, characterized in that: The feeding unit includes a metal conductive inner core, an insulating sleeve, an outer conductor and a protective sleeve which are coaxially arranged in sequence from the inside to the outside; the metal conductive inner core is connected to a feeding point on one of the L-shaped metal strips, the outer conductor is connected to the other L-shaped metal strip, and the metal conductive inner core is coaxially arranged with one side of the other L-shaped metal strip.

7. The antenna unit supporting dual-frequency satellite communication according to claim 1, characterized in that: The dielectric layer is made of composite ceramic material.

8. An antenna assembly, characterized in that: include: A shell, a simulated metal floor and an antenna unit supporting dual-frequency satellite communications as described in any one of claims 1-6, wherein the antenna unit and the simulated metal floor are arranged in the shell.

9. The antenna assembly according to claim 8, characterized in that: The antenna assembly also includes a battery disposed within the housing.

10. A terminal device, characterized in that: It comprises the antenna unit supporting dual-frequency satellite communication as described in any one of claims 1-7, or the antenna assembly as described in any one of claims 8-9.

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