Adaptive Attitude Change Antenna Directional Communication Method and Communication Device

Abstract

The present invention discloses an antenna directional communication method adaptable to pose changes, which includes a first communication end and a second communication end. The first communication end includes an antenna, and the second communication end includes a reconfigurable directional antenna and a control unit. The first communication end and the second communication end communicate with each other through the antenna and the reconfigurable directional antenna. The control unit acquires the position information of the first communication end, the position information and attitude information of the second communication end, calculates the desired antenna pointing of the reconfigurable directional antenna from the position information and attitude information, and then controls the reconfigurable directional antenna to change the radiation pattern according to the desired antenna pointing. The first communication end and the second communication end communicate with each other through the antenna and the reconfigurable directional antenna with the changed radiation pattern. The present invention also discloses an antenna directional communication device adaptable to pose changes. The present invention meets the control requirements for landing gears and hatches, and is flexible and portable.

Description

Technical Field

[0001] The present invention relates to an antenna directional communication method and a communication device, in particular to an antenna directional communication method and a communication device that adapt to pose changes. Background Art

[0002] An antenna is a front-end component of a wireless communication system, and its performance affects the quality and reliability of the entire wireless communication system. To increase the communication distance, an effective means is to increase the gain of the antenna and improve the energy usage efficiency, that is, to concentrate the energy of the antenna in a certain direction and aim at the other end of the communication device. However, in scenarios using wireless and long-distance transmission, the antenna is often not fixedly installed. Usually, one communication end is fixedly installed at a certain position, such as a mobile base station, but the other communication end is in a moving state, such as a moving aircraft, vehicle, ship, person, etc. At this time, the aiming direction of the directional antenna needs to change in real time, otherwise the communication quality will be seriously degraded, and even communication interruption may occur. For example, when an airplane is flying in the air, its absolute geographical coordinates, pitch angle, roll angle, yaw angle, etc. are always changing. At this time, if it is necessary to accurately aim at a certain target or communication tower on the ground end, the sway of the airplane and the measurement errors of the sway angle and angular velocity will cause deviations in the antenna's observation of the target, thereby affecting the target tracking accuracy of the antenna. Summary of the Invention

[0003] Aiming at the above-mentioned defects of the prior art, the task of the present invention is to provide an antenna directional communication method that adapts to pose changes to solve the problem of poor communication caused by the misalignment of the antenna due to the position and attitude changes of the airplane. Another task of the present invention is to provide a communication device that adapts to pose changes.

[0004] The technical solution of the present invention is as follows: An antenna directional communication method that adapts to pose changes, including a first communication end and a second communication end. The first communication end includes an antenna, and the second communication end includes a reconfigurable directional antenna and a control unit. The first communication end and the second communication end communicate with each other through the antenna and the reconfigurable directional antenna. The control unit acquires the position information of the first communication end, the position information and attitude information of the second communication end, calculates the expected antenna pointing of the reconfigurable directional antenna from the position information and attitude information, and controls the reconfigurable directional antenna to change the radiation pattern according to the expected antenna pointing. The first communication end and the second communication end communicate with each other through the antenna and the reconfigurable directional antenna with the changed radiation pattern.

[0005] Further, the position information among the position information of the first communication end, the position information of the second communication end, and the attitude information is the position information determined by a positioning device, and the attitude information is the pitch angle, roll angle, and yaw angle determined by an attitude sensor.

[0006] Further, the calculation of the desired antenna pointing of the reconfigurable directional antenna is specifically as follows: establish a spatial rectangular coordinate system, set the second communication end in the initial attitude as a square plane and place it in the XOY plane of the spatial rectangular coordinate system, with the X-axis pointing to the head of the second communication end, the Y-axis pointing to the left of the second communication end, the Z-axis upward, and the center of the square plane coinciding with the origin of the coordinate system. Calculate the angle between the unit vector of the Z-axis of the second communication end in the initial attitude after the attitude change of the second communication end and the line connecting the first communication end to the origin of the coordinate system.

[0007] Further, the angle between the unit vector of the Z-axis of the second communication end in the initial attitude after the attitude change of the second communication end and the line connecting the first communication end to the origin of the coordinate system includes the antenna direction angle α and the antenna yaw angle β.

[0008]

[0009]

[0010]

[0011] where α ∈ [0, π / 2], x, y, z are the coordinates of the first communication end in the spatial rectangular coordinate system, θ is the pitch angle of the second communication end. is the roll angle of the second communication end, and Ψ is the yaw angle of the second communication end.

[0012] A communication device with adaptive pose change includes a first communication end and a second communication end. The first communication end includes an antenna and a first information processing unit. The second communication end includes a reconfigurable directional antenna, a control unit, a second information processing unit, a position sensor, and an attitude sensor. The first communication end and the second communication end communicate with each other through the antenna and the reconfigurable directional antenna. The first information processing unit and the second information processing unit are used to receive and send communication service information. The control unit is connected to the reconfigurable directional antenna, the position sensor, and the attitude sensor, and the control unit executes the antenna directional communication method with adaptive pose change.

[0013] Further, the position sensor is a satellite navigation positioning device or an indoor wireless positioning device, and the attitude sensor includes a gyroscope, an accelerometer, and a compass.

[0014] Further, the antenna of the first communication end is a directional antenna or an omnidirectional antenna, and one or more are provided at the second communication end.

[0015] The advantages of the present invention compared with the prior art are as follows:

[0016] The adaptive pose change antenna directional communication method proposed in this patent adopts the method of directional antenna transceiver and the pose change adaptive algorithm to a great extent, effectively eliminating the problem of directional antenna alignment caused by the position and pose changes of the communication end due to movement, ensuring real-time and reliable communication during movement, improving the fluency of communication and the accuracy of transmitted data, and enhancing the signal strength. The present invention can achieve reliable communication between point-to-point or point-to-multipoint targets, effectively prevent communication loss when the target changes its pose, and is compatible with common communication standards, making it simple and fast to use. Description of the Drawings

[0017] Figure 1 Schematic diagram of the communication device module with adaptive pose change for the embodiment.

[0018] Figure 2 Schematic diagram of the positional relationship between the first communication end and the second communication end.

[0019] Figure 3 Schematic diagram of the reconfigurable directional antenna. Detailed Embodiment

[0020] The present invention will be further described below in conjunction with the embodiments, but it is not intended to limit the present invention.

[0021] Embodiment, please refer to Figure 1As shown in the figure, the communication device with adaptive pose change in this embodiment includes a first communication end 1 and a second communication end 2. The first communication end 1 includes an antenna 101 and a first information processing unit 102. The antenna 101 can be a directional antenna (suitable for point-to-point communication with the second communication end) or an omnidirectional antenna (suitable for point-to-multipoint communication with multiple devices of the same type as the second communication end). The first information processing unit 102 includes frequency conversion and signal processing devices that a communication system must include, as well as a single-chip microcomputer, an embedded system, and a PC device for processing service data. The second communication end 2 is a movable platform, which includes a reconfigurable directional antenna 201, a control unit 202, a second information processing unit 203, and a position and attitude sensor 204. The reconfigurable directional antenna 201 is composed of phase-controllable units arranged in a two-dimensional pattern. The second information processing unit 203 is the same as the first information processing unit 102. However, since the second communication end 2 is usually a movable platform, a single-chip microcomputer and an embedded system are generally used to process service data. The control unit 202 can be composed of electronic devices such as an FPGA and a single-chip microcomputer with the capabilities of operation, memory, and output control. It executes the antenna directional communication method with adaptive pose change and outputs the azimuth angle and horizontal angle of the antenna pattern to control the reconfigurable directional antenna 201. The position and attitude sensor 204 is connected to the control unit 202 and includes a position sensor and an attitude sensor. The position sensor can be a satellite navigation and positioning device, such as a GPS or Beidou satellite positioning module, or an indoor wireless positioning device, such as a UWB positioning module. The attitude sensor includes a gyroscope, an accelerometer, and a compass, which can accurately sense and output the attitude of the second communication end. The first communication end 1 and the second communication end 2 establish a radio connection through the antenna 101 and the reconfigurable directional antenna 201 to communicate with each other, including but not limited to motion control instructions and sensing data collected by the platform.

[0022] Please refer to Figure 2 As shown in the figure, the specific process of executing the antenna directional communication method with adaptive pose change is that after the position and attitude of the second communication end 2 change, the control unit 202 calculates the expected antenna pointing of the reconfigurable directional antenna 201, that is, obtains the azimuth angle and horizontal angle of the antenna pattern. Let's assume that the second communication end 2 is a square plane. Place it in a three-dimensional rectangular coordinate system and make its initial position on the XOY plane. At this time, the x-axis points to the head, the y-axis points to the left, the z-axis points upward, and the center point of the square plane coincides with the origin of the coordinate system. For the convenience of subsequent angle calculation, make a unit vector from the center point of the plane in the direction of the Z-axis, denoted as r. In this way, when the platform moves at any pitch angle, yaw angle, and roll angle, the angle formed by the line connecting the coordinates of the first communication end 1 and the origin and the deflected r vector is the angle to be studied.

[0023] For the calculation of the azimuth angle, the calculation formula for the rotation of a vector around a fixed axis is the Rodriguez rotation formula, which is used to calculate the new vector obtained by rotating a vector around a rotation axis by a given angle in three-dimensional space. The specific formula is as follows:

[0024] Let v be a three-dimensional vector and k be the unit vector of the rotation axis. Then the vector obtained by rotating v around the rotation axis k by an angle θ in the sense of the right-hand screw rule can be represented by the frame composed of three non-coplanar vectors v, k, and k×v:

[0025] v rot = v·cosθ+(1 - cosθ)·(v·k)·k+sinθ·(k×v). For the convenience of calculation, the matrix form of this formula is adopted. That is, if k and v are written as column vectors respectively:

[0026]

[0027] Then the rotated vector can be expressed as: v rot = Rv, where

[0028]

[0029] where E is the 3×3 identity matrix. It should be noted that the second term in the formula is not a dot product but a tensor product, resulting in a 3×3 matrix. Through this formula, the calculation process can be simplified.

[0030] First, consider the pitch angle θ, which is equivalent to rotating the vector (0, 0, -1) around the y-axis by an angle θ. Let the rotation axis be (0, 1, 0). Using the formula, the following equation can be obtained:

[0031]

[0032]

[0033] Next, consider the roll angle φ. The rotation axis of this angle is relatively complex and is equivalent to the new vector obtained by deflecting the vector (1, 0, 0) by the pitch angle θ. After calculation, the rotation axis of the roll angle can be obtained:

[0034]

[0035] Using the formula, the transformation matrix R2 can be calculated:

[0036]

[0037] Thus, we have:

[0038]

[0039] Finally, consider the yaw angle Ψ, which is equivalent to rotating v2 around the z-axis by an angle Ψ. For the convenience of calculation, let the rotation axis be (0, 0, 1) here. Using the formula, the rotation matrix R3 can be obtained:

[0040]

[0041] Thus, we have

[0042] So far, the vector v3 obtained after the initial v(0, 0, -1) undergoes certain pitch angle, roll angle, and yaw angle changes has been calculated. Let the coordinates of the first communication terminal 1 in the coordinate system be (x, y, z). At this time, using the vector included angle formula the cosine value of the required included angle can be obtained. The cosine value is

[0043]

[0044] where α ∈ [0, π / 2|. Therefore, the unique α can be obtained, which is the included angle between the vector from the origin to the first communication terminal 1 in the platform coordinate system and the Z-axis, that is, the direction angle of the directional antenna beam.

[0045] For the calculation of the horizontal angle, take the center of the platform as the origin and establish a NED (North-East-Down) reference system. Let the coordinates of the first communication terminal 1 in the aforementioned platform coordinate system be (x, y, z). Then the coordinates of the first communication terminal 1 in the body coordinate system (FRD (Front-Right-Down) reference system) can be obtained from the transformation matrix.

[0046] The rotation matrix for transforming the platform coordinate system (ground coordinate system) to the body coordinate system is:

[0047]

[0048] Since the above NED system has the same attitude as the ground system (also NED system), and the origins of the NED system and the body coordinate system coincide, the transformation matrix from the NED system coordinates to the body coordinate system coordinates is The transformed coordinates are:

[0049]

[0050] After obtaining the coordinates of the first communication terminal 1 in the body coordinate system, the target yaw angle of the antenna in the body coordinate system can be calculated:

[0051]

[0052] It should be noted that the horizontal angle in the due front direction (X-axis of the body coordinate system) is 0.

[0053] Using the calculated direction angle and yaw angle as the expected values to control the reconfigurable directional antenna 201 to change the radiation pattern. Please refer to Figure 3As shown, assume that the element size of the reconfigurable directional antenna 201 is D, and the phase of the m-th element in the x direction and the n-th element in the y direction is The number of elements in the x direction is M, and the number in the y direction is N. The radiation pattern calculation formula of the entire reconfigurable directional antenna 201 is:

[0054]

[0055] Therefore, the radiation pattern of the reconfigurable directional antenna 201 can be controlled by controlling the phase of each element. For the specific control of the reconfigurable directional antenna 201, please refer to the technology disclosed in Cui T J, Qi M Q, Wan X, et al. Coding metamaterials, digital metamaterials and programmable metamaterials [J]. Light: Science & Applications, 2014, 3(10): e218-e218., which will not be elaborated here. Finally, the first communication terminal 1 and the second communication terminal 2 communicate with each other through the antenna of the first communication terminal 1 and the reconfigurable directional antenna 201 with the changed radiation pattern to ensure the communication quality.

Claims

1. An antenna directional communication method adaptable to pose changes, characterized in that It includes a first communication terminal and a second communication terminal. The first communication terminal includes an antenna, and the second communication terminal includes a reconfigurable directional antenna and a control unit. The first communication terminal and the second communication terminal communicate with each other through the antenna and the reconfigurable directional antenna. The control unit obtains the position information of the first communication terminal, the position information of the second communication terminal, and the attitude information, calculates the expected antenna pointing of the reconfigurable directional antenna from the position information and the attitude information, and then controls the reconfigurable directional antenna to change the radiation pattern according to the expected antenna pointing. The first communication terminal and the second communication terminal communicate with each other through the antenna and the reconfigurable directional antenna with the changed radiation pattern; The specific calculation of the expected antenna pointing of the reconfigurable directional antenna is as follows: establish a spatial rectangular coordinate system. Assume that the second communication terminal in the initial attitude is a square plane and is placed in the XOY plane of the spatial rectangular coordinate system, with the X-axis pointing to the head of the second communication terminal, the Y-axis pointing to the left of the second communication terminal, and the Z-axis upward. The center of the square plane coincides with the origin of the coordinate system. Calculate the angle between the unit vector of the Z-axis of the second communication terminal in the initial attitude after the attitude change of the second communication terminal and the line connecting the first communication terminal to the origin of the coordinate system. The angle between the unit vector of the Z-axis of the second communication terminal in the initial attitude after the attitude change of the second communication terminal and the line connecting the first communication terminal to the origin of the coordinate system includes the antenna direction angle α and the antenna yaw angle β. where α ∈ [0, π / 2], x, y, z are the coordinates of the first communication end in the spatial rectangular coordinate system, θ is the pitch angle of the second communication end, is the roll angle of the second communication end, and Ψ is the yaw angle of the second communication end.

2. The adaptive attitude change-based antenna directional communication method according to claim 1, characterized in that The position information in the position information of the first communication terminal, the position information of the second communication terminal, and the attitude information is the position information determined by a positioning device, and the attitude information is the pitch angle, roll angle, and yaw angle determined by an attitude sensor.

3. An antenna directional communication device with adaptive pose change, characterized in that It includes a first communication terminal and a second communication terminal. The first communication terminal includes an antenna and a first information processing unit, and the second communication terminal includes a reconfigurable directional antenna, a control unit, a second information processing unit, a position sensor, and an attitude sensor. The first communication terminal and the second communication terminal communicate with each other through the antenna and the reconfigurable directional antenna. The first information processing unit and the second information processing unit are used to receive and send communication service information. The control unit is connected to the reconfigurable directional antenna, the position sensor, and the attitude sensor, and the control unit executes the adaptive pose change antenna directional communication method according to claim 1 or 2.

4. The antenna directional communication device with adaptive pose change according to claim 3, characterized in that, The position sensor is a satellite navigation positioning device or an indoor wireless positioning device, and the attitude sensor includes a gyroscope, an accelerometer, and a compass.

5. The antenna directional communication device with adaptive pose change according to claim 3, characterized in that, The antenna of the first communication terminal is a directional antenna or an omnidirectional antenna, and the second communication terminal is provided with one or more.

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