Radar and unmanned aerial vehicle

Abstract

The invention relates to a radar and an unmanned aerial vehicle, the radar comprises a radio frequency module, a signal processing module and an antenna module, the radio frequency module comprises a first radio frequency chip and a second radio frequency chip, the signal processing module is connected with the radio frequency module, and the antenna module comprises a beam scanning antenna, a transmitting antenna and a receiving antenna. At least one of the transmitting antenna and the beam scanning antenna is used for transmitting signals to a target, and the receiving antenna is used for receiving signals reflected by the target; the first radio frequency chip is used for transmitting a signal to a target through the beam scanning antenna so as to improve the scanning intensity of the radar on the scanning edge in the azimuth direction, and meanwhile, compared with fixed beam scanning, the azimuth beam is narrower, so that the radar has better beam directivity when in the second scanning mode, and the scanning efficiency is improved. The accuracy and the reliability of a scanning result of a radar on a target at a beam edge are improved.

Description

Technical Field

[0001] This application relates to the technical field of unmanned aerial vehicles, and particularly to a radar and an unmanned aerial vehicle. Background Art

[0002] During flight, an unmanned aerial vehicle needs to scan nearby targets to determine the angles and distances of the targets relative to the unmanned aerial vehicle in the azimuth and pitch directions, and to determine the sizes of the targets in the azimuth and pitch directions, so that the unmanned aerial vehicle can fly accurately towards the targets or avoid the targets accurately.

[0003] In the prior art, the radar of an unmanned aerial vehicle is a 4D millimeter-wave radar with fixed transmitting and receiving beams. Its typical architecture is a layout of 2 transmitting antennas and 4 receiving antennas, and the structures of the transmitting antennas and receiving antennas are the same. The transmitting antennas are arranged at intervals in the azimuth and pitch directions. When the radar works, the 2 transmitting antennas alternately transmit electromagnetic waves, and the receiving antennas receive the electromagnetic waves returned by the targets. According to the radar principle, a single receiving antenna can obtain the distance and speed information of the targets from the returned electromagnetic waves, and multiple antennas can obtain the angle information of the targets. Since the transmitting antennas and receiving antennas are arranged both horizontally and vertically, such an antenna arrangement design can achieve azimuth angle measurement and pitch angle measurement, thereby obtaining 4D scanning information of the distance, speed, azimuth angle, and pitch angle of the targets.

[0004] However, the radar scanning method in the prior art is fixed-beam scanning, and the range of the beam is the scanning range of the radar angle; but the antenna gain at the beam edge relative to the beam center is reduced by about 5 - 10 dB, resulting in insufficient scanning ability of the radar for the targets at the antenna beam edge. Summary of the Invention

[0005] This application provides a radar and an unmanned aerial vehicle, which can improve the scanning ability of the radar for the targets at the antenna beam edge.

[0006] In the first aspect of this application, a radar is provided, which includes a radio frequency module, a signal processing module, and an antenna module. The radio frequency module includes a first radio frequency chip and a second radio frequency chip. The signal processing module is connected to the radio frequency module. The antenna module includes a beam scanning antenna, a transmitting antenna, and a receiving antenna. At least one of the transmitting antenna and the beam scanning antenna is used to transmit signals to the target, and the receiving antenna is used to receive the signals reflected by the target. The beam scanning antenna includes a phase shifter network, a first radio frequency antenna, and a second radio frequency antenna. The first radio frequency chip is connected to the first radio frequency antenna and the second radio frequency antenna respectively through the phase shifter network. The transmitting antenna is connected to the second radio frequency chip. The receiving antenna includes a first receiving antenna and a second receiving antenna. The first receiving antenna and the second receiving antenna are respectively connected to the radio frequency module. The second radio frequency chip is used to transmit signals to the target through the transmitting antenna. The first radio frequency chip is used to transmit signals to the target through the beam scanning antenna.

[0007] In the present application, by providing a first radio frequency chip, a second radio frequency chip, and a beam scanning antenna, the radar has a second scanning mode, which improves the scanning intensity of the radar at the scanning edge in the azimuth direction, that is, the gain of the scanning beam of the radar is increased at azimuth angles of ±50°. At the same time, compared with fixed beam scanning, the azimuth beam is narrower, so that the radar has better beam directivity when in the second scanning mode, thereby improving the accuracy and reliability of the scanning result of the radar for the targets at the beam edge.

[0008] In some embodiments, the radio frequency module further includes a third radio frequency chip, and the third radio frequency chip is respectively connected to the first radio frequency antenna and the second radio frequency antenna through a phase shift network; when the third radio frequency chip transmits a signal to a target through the beam scanning antenna, the radar is in the second scanning mode.

[0009] In some embodiments, the phase shift network includes a 3dB coupler and a cross-coupler. The 3dB coupler is connected to the cross-coupler, and the first radio frequency chip and the third radio frequency chip are respectively connected to the 3dB coupler; the beam scanning antenna further includes a third radio frequency antenna and a fourth radio frequency antenna, and the first radio frequency antenna, the second radio frequency antenna, the third radio frequency antenna, and the fourth radio frequency antenna are respectively connected to the cross-coupler.

[0010] In some embodiments, the transmitting antenna includes a first transmitting antenna, and the first transmitting antenna is connected to the second radio frequency chip. The antenna aperture of the first transmitting antenna and the antenna aperture of the beam scanning antenna are distributed along the pitch direction; in the pitch direction, the distance between the antenna aperture of the first transmitting antenna and the antenna aperture of the beam scanning antenna is L1, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L1 ≤ λ / 2.

[0011] In some embodiments, the transmitting antenna further includes a second transmitting antenna, and the second transmitting antenna is connected to the second radio frequency chip.

[0012] In some embodiments, the radio frequency module further includes a fourth radio frequency chip, and the second transmitting antenna is connected to the fourth radio frequency chip.

[0013] In some embodiments, when the second transmitting antenna is connected to the fourth radio frequency chip, along the pitch direction, the second transmitting antenna is located on the side of the first transmitting antenna away from the beam scanning antenna; in the pitch direction, the distance between the antenna aperture of the second transmitting antenna and the antenna aperture of the first transmitting antenna is L2, then L2 ≤ λ / 2; in the azimuth direction, the distance between the antenna aperture of the second transmitting antenna and the antenna aperture of the first transmitting antenna is L3, then L3 ≤ λ / 2.

[0014] In some embodiments, when the first radio frequency chip transmits a signal, the antenna aperture of the beam scanning antenna is located at a first position, and when the third radio frequency chip transmits a signal, the antenna aperture of the beam scanning antenna is located at a second position. The first position and the second position are distributed along the azimuth direction. Along the azimuth direction, the distance between the first position and the second position is L4, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L4 ≤ λ / 2.

[0015] In some embodiments, the receiving antenna further includes a third receiving antenna. The third receiving antenna is connected to the first radio frequency chip, the third radio frequency chip, or the second radio frequency chip. The antenna apertures of the first receiving antenna, the second receiving antenna, and the third receiving antenna are arranged along the azimuth direction.

[0016] The second aspect of the present application provides a drone, which includes a fuselage, the radar described in any one of the above, and a power module. The radar and the power module are both installed on the fuselage, and the power module is connected to the radio frequency module and the signal processing module.

[0017] In the present application, within the scanning range of the drone, compared with the fixed beam, the azimuth beam increases the beam gain at the scanning edge of the drone, thereby improving the scanning accuracy of the drone for the targets at the scanning edge, so as to improve the accuracy and reliability of the scanning results of the drone.

[0018] It should be understood that the above general description and the following detailed description are only exemplary and do not limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of signal transmission of some hardware of the radar provided by the present application in an embodiment;

[0020] Figure 2 is Figure 1 The structural schematic diagram of the radio frequency module in an embodiment;

[0021] Figure 3 is Figure 1 The connection structure schematic diagram of the antenna module and the radio frequency module in an embodiment;

[0022] Figure 4 is Figure 3 The structural schematic diagram of the phase shift network in an embodiment;

[0023] Figure 5 is Figure 3 The schematic diagram of the distribution position of the antenna aperture when the antenna module in an embodiment is working;

[0024] Figure 6 is Figure 3Schematic diagram of the distribution positions of the first, second, third, and fourth types of antenna apertures of the receiving antenna when the four output ports

[0025] Figure 7 Schematic diagram of the connection structure of the radar provided in this application in one embodiment;

[0026] Figure 8 Electromagnetic calculation results of the scanning beams of the radar provided in this application in three scanning modes.

[0027] Reference numerals:

[0028] 1 - RF module;

[0029] 11 - First RF chip;

[0030] 111 - First output port;

[0031] 112 - Second output port;

[0032] 113 - First input port;

[0033] 114 - Second input port;

[0034] 12 - Second RF chip;

[0035] 121 - Third output port;

[0036] 122 - Fourth output port;

[0037] 123 - Third input port;

[0038] 124 - Fourth input port;

[0039] 13 - Third RF chip;

[0040] 131 - Fifth output port;

[0041] 132 - Sixth output port;

[0042] 133 - Fifth input port;

[0043] 134 - Sixth input port;

[0044] 14 - Fourth RF chip;

[0045] 141 - Seventh output port;

[0046] 142 - Eighth output port;

[0047] 143 - Seventh input port;

[0048] 144 - Eighth input port;

[0049] 15 - Power divider;

[0050] 2 - Signal processing module;

[0051] 3 - Antenna module;

[0052] 31 - Beam scanning antenna;

[0053] 311 - Phase shifter network;

[0054] 311a - 3dB coupler;

[0055] 311b - Cross - coupler;

[0056] 311c - First sub - output port;

[0057] 311d - Second sub - output port;

[0058] 311e - Third sub - output port;

[0059] 311f - Fourth sub - output port;

[0060] 312 - First RF antenna;

[0061] 313 - Second RF antenna;

[0062] 314 - Third RF antenna;

[0063] 315 - Fourth RF antenna;

[0064] 316 - First output antenna aperture;

[0065] 317 - Second output antenna aperture;

[0066] 32 - Transmitting antenna;

[0067] 321 - First transmitting antenna;

[0068] 321a - Third output antenna aperture;

[0069] 322 - Second transmitting antenna;

[0070] 322a - Fourth output antenna aperture;

[0071] 33 - Receiving antenna;

[0072] 331 - First receiving antenna;

[0073] 332 - Second receiving antenna;

[0074] 333 - Third receiving antenna;

[0075] 334 - Fourth receiving antenna;

[0076] 335 - Fifth receiving antenna;

[0077] 336 - Sixth receiving antenna;

[0078] 337 - Seventh receiving antenna;

[0079] 338 - Eighth receiving antenna;

[0080] 34 - First input antenna aperture;

[0081] 35 - Second input antenna aperture;

[0082] 36 - Third input antenna aperture;

[0083] 37 - Fourth input antenna aperture;

[0084] 38 - Fifth input antenna aperture;

[0085] 39 - Sixth input antenna aperture;

[0086] 3a - Seventh input antenna aperture;

[0087] 3b - Eighth input antenna aperture;

[0088] 3c - First type of antenna aperture;

[0089] 3d - Second type of antenna aperture;

[0090] 3e - Third type of antenna aperture;

[0091] 3f - Fourth type of antenna aperture;

[0092] 4 - Power supply module.

[0093] The accompanying drawings here are incorporated into and constitute a part of this specification, showing embodiments consistent with this application and used together with the specification to explain the principles of this application. Detailed implementation manners

[0094] To better understand the technical solutions of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0095] It should be clear that the described embodiments are only a part of the embodiments of this application, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope protected by this application.

[0096] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "the", and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise.

[0097] It should be understood that the term "and / or" used herein is merely a description of the associated relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally indicates that the associated objects before and after are in an "or" relationship.

[0098] It should be noted that the orientation terms such as "upper", "lower", "left", and "right" described in the embodiments of the present application are described from the perspective shown in the drawings and should not be construed as a limitation on the embodiments of the present application. In addition, in the context, it should also be understood that when it is mentioned that an element is connected "above" or "below" another element, it can not only be directly connected "above" or "below" another element, but also be indirectly connected "above" or "below" another element through an intermediate element.

[0099] The embodiments of the present application provide a drone, which includes a fuselage, a radar and a power module installed on the fuselage. As Figure 1 shown, the radar includes a radio frequency module 1, a signal processing module 2 and an antenna module 3. The power module is used to supply power to the signal processing module 2 and the radio frequency module 1 to maintain the stable operation of the signal processing module 2 and the radio frequency module 1. The signal processing module 2 and the antenna module 3 are respectively connected to the radio frequency module 1. The signal processing module 2 can control the radio frequency module 1 to transmit signals to the antenna module 3. The antenna module 3 transmits the signals to the target to be scanned. The signals reflected back by the target are transmitted to the signal processing module 2 through the antenna module 3 and the radio frequency module 1. The signal processing module 2 calculates the direction and distance of the target according to the reflected signals, so as to facilitate the drone to fly towards the target or to avoid the target during the flight of the drone.

[0100] As Figure 2 、 Figure 3 and Figure 7As shown in the figure, the radio frequency module 1 includes a first radio frequency chip 11 and a second radio frequency chip 12. The antenna module 3 includes a beam scanning antenna 31, a transmitting antenna 32, and a receiving antenna 33. At least one of the transmitting antenna 32 and the beam scanning antenna 31 is used to transmit a signal to a target, and the receiving antenna 33 is used to receive the signal reflected by the target. The beam scanning antenna 31 includes a phase shifter network 311, a first radio frequency antenna 312, and a second radio frequency antenna 313. The first radio frequency chip 11 is connected to the first radio frequency antenna 312 and the second radio frequency antenna 313 respectively through the phase shifter network 311. The transmitting antenna 32 is connected to the second radio frequency chip 12. The receiving antenna 33 includes a first receiving antenna 331 and a second receiving antenna 332. The first receiving antenna 331 and the second receiving antenna 332 are respectively connected to the radio frequency module 1. The second radio frequency chip 12 is used to transmit a signal to the target through the transmitting antenna 32. At this time, the radar emits a fixed beam to the scanned target, so that the radar is in the first scanning mode. The first radio frequency chip 11 is used to transmit a signal to the target through the beam scanning antenna 31. At this time, the radar emits an azimuth beam to the scanned target, so that the radar is in the second scanning mode.

[0101] When the radar is in the first scanning mode, the signal beam emitted by the radar is a fixed beam. The shape of the fixed beam and the gain in the azimuth angle are as Figure 8 shown. The signal processing module 2 controls the second radio frequency chip 12 to transmit a signal to the transmitting antenna 32. The transmitting antenna 32 radiates the signal outside the UAV. When the signal reaches the target surface, the signal is reflected back to the radar by the target. The reflected signal is transmitted to the signal processing module 2 through the receiving antenna 33 and the radio frequency module 1. The signal processing module 2 calculates and judges the position, angle, and size information of the target in the azimuth direction X according to the reflected signal. Among them, as Figure 8 shown, in the fixed mode scanning mode, when the azimuth angle is 0°, that is, when the target is directly in front of the UAV, the gain of the fixed beam is the largest and the scanning effect is the best. When the target is in the front left or front right of the UAV, as the azimuth angle increases, the gain of the fixed beam gradually decreases, making the scanning effect of the fixed beam gradually worse. When the UAV scans within the preset azimuth angle range, for example, the scanning angle of the UAV in the azimuth direction X is α, -50° ≤ α ≤ 50°. At this time, the gain of the fixed beam at the scanning edge of the UAV is small, making the scanning effect at the scanning edge poor, thus making the scanning accuracy of the target at the scanning edge of the UAV poor.

[0102] Therefore, when it is necessary to scan the target in the front left or front right of the UAV, the radar can be switched to the second scanning mode. At this time, the signal emitted by the first radio frequency chip 11 is divided into at least two sub-signals by the phase shifter network 311, and the phase difference between the sub-signals is greater than zero, so that the signal beam emitted by the radar is an azimuth beam, as Figure 8As shown in FIG. 1 , taking -30° scanning beam and +30° scanning beam as examples, the azimuth beam has the largest gain when the azimuth angle is -30° or +30°. As the azimuth angle changes, the gain of the azimuth beam gradually decreases. Figure 8 As shown, within the scanning range of the UAV, the azimuth beam increases the beam gain of the UAV's scanning edge compared to the fixed beam, thereby improving the UAV's scanning accuracy for targets at the scanning edge, so as to improve the accuracy and reliability of the scanning results of targets at the beam edge of the radar and the UAV.

[0103] Among them, Figure 8 As shown, when the azimuth angle is between ±50°, the gains of the fixed beam and the azimuth beam are relatively large. Therefore, in an embodiment of the present application, the scanning angle of the UAV in the azimuth direction is between ±50°, which can improve the scanning effect of the radar and the UAV, and further improve the working stability and reliability of the radar and the UAV.

[0104] like Figure 2 , Figure 3 and Figure 7 As shown, the RF module 1 also includes a third RF chip 13, which is respectively connected to the first RF antenna 312 and the second RF antenna 313 through a phase shift network 311; when the third RF chip 13 transmits a signal to the target through the beam scanning antenna 31, the radar is in the second scanning mode.

[0105] A first RF chip 11 and a third RF chip 13 connected to a phase shift network 311 are provided at the same time. The signal transmitted by the first RF chip 11 is coupled and adjusted to a first azimuth beam through the phase shift network 311. For example, the first azimuth beam is a +30° scanning beam, so that the radar is in a first sub-scanning mode. The signal transmitted by the third RF chip 13 is coupled and adjusted to a second azimuth beam through the phase shift network 311. For example, the second azimuth beam is a -30° scanning beam, so that the radar is in a second sub-scanning mode. During the operation of the radar, the radar can selectively strengthen the scanning edge of the left azimuth and / or the scanning edge of the right azimuth to further improve the scanning effect of the radar.

[0106] Among them, during the operation of the radar and the drone, the user can adjust the scanning mode of the radar through the signal processing module 2 according to the scanning requirements, and / or the radar switches between the first scanning mode, the first sub-scanning mode and the second sub-scanning mode during operation.

[0107] Specifically, Figure 4As shown, the phase-shifting network 311 includes a 3dB coupler 311a and a cross-coupler 311b. The 3dB coupler 311a is connected to the cross-coupler 311b. The first radio frequency chip 11 and the third radio frequency chip 13 are respectively connected to the 3dB coupler 311a; As Figure 3 shown, the beam scanning antenna 31 further includes a third radio frequency antenna 314 and a fourth radio frequency antenna 315. The cross-coupler 311b is provided with a first sub-output port 311c, a second sub-output port 311d, a third sub-output port 311e, and a fourth sub-output port 311f. The first radio frequency antenna 312 is connected to the first sub-output port 311c, the second radio frequency antenna 313 is connected to the second sub-output port 311d, the third radio frequency antenna 314 is connected to the fourth sub-output port 311f, and the fourth radio frequency antenna 315 is connected to the fourth sub-output port 311f.

[0108] When the radar is in the first sub-scanning mode, the first radio frequency chip 11 transmits a first signal with a power of P1 and a phase of θ m1 . The first signal passes through the 3dB coupler 311a and the cross-coupler 311b and then outputs four sub-signals. The powers and phases of the four sub-signals are P 11 , θ m11 , P 12 , θ m12 , P 13 , θ m13 , P 14 and θ m14 respectively. Among them, P 11 = P 12 = P 13 = P 14 = P1 / 4, That is, the power of the four sub-signals is 1 / 4 of the power of the first signal, and the phase difference between adjacent two sub-signals is The antenna beam scanning angle is determined by the following beam scanning formula:

[0109]

[0110] Among them, θ1 is the azimuth angle with the maximum azimuth beam gain, d = λ / 2, where λ is the wavelength of the electromagnetic wave emitted by the radar, that is, the wavelength of the first signal; Substituting the parameter values into the beam scanning formula, we get θ1 = 30°, that is, the antenna realizes an azimuth beam scanning of +30°.

[0111] When the radar is in the second sub-scanning mode, the third radio frequency chip 13 transmits a second signal with a power of P2 and a phase of θ m2 . The second signal passes through the 3dB coupler 311a and the cross-coupler 311b and then outputs four sub-signals. The powers and phases of the four sub-signals are P21 , θ m21 , P 22 , θ m22 , P 23 , θ m23 , P 24 and θ m24 , where P 21 = P 22 = P 23 = P 24 = P2 / 4, That is, the power of the four sub-signals is 1 / 4 of the power of the first signal, and the phase difference between two adjacent sub-signals is where θ2 is the azimuth angle at which the second azimuth beam gain is maximum. Substituting the parameter values into the beam scanning formula gives θ2 = -30°, that is, the antenna realizes azimuth beam scanning of -30°.

[0112] Taking the azimuth beam scanning of ±30° as an example above, if azimuth beam scanning of ±10°, ±20°, ±40° or other angles is required, adjusting the phase shift network 311 can achieve it. The specific angles of azimuth beam scanning in the embodiments of the present application are not particularly limited.

[0113] Specifically, as Figure 5 shown, when the first radio frequency chip 11 transmits a signal, the antenna aperture of the beam scanning antenna 31 is the first output antenna aperture 316 located at the first position. When the target reflects the signal back to the receiving antenna 33, as Figure 6 shown, a first type of antenna aperture 3c is formed at the receiving antenna 33; when the third radio frequency chip 13 transmits a signal, as Figure 5 shown, the antenna aperture of the beam scanning antenna 31 is the second output antenna aperture 317 located at the second position. When the target reflects the signal back to the receiving antenna 33, as Figure 6 shown, a second type of antenna aperture 3d is formed at the receiving antenna 33; where the first position and the second position are distributed along the azimuth direction X, and along the azimuth direction X, the distance between the first position and the second position is L4, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L4 ≤ λ / 2.

[0114] In this embodiment, if L4 > λ / 2, there will be a grating lobe effect, that is, the multi-valuedness of the detection angle appears, thus affecting the radar scanning result. Therefore, L4 ≤ λ / 2, reducing the risk of the grating lobe effect during the radar scanning process, and further improving the accuracy and reliability of the radar scanning result.

[0115] Preferably, L4 = λ / 2 to increase the installation space of the first radio frequency chip 11, the second radio frequency chip 12 and the beam scanning antenna 31, and further reduce the installation difficulty.

[0116] In one embodiment, the number of transmitting antennas 32 is one, that is, the transmitting antenna 32 only includes the first transmitting antenna 321. The first transmitting antenna 321 is connected to the second radio frequency chip 12, and the antenna aperture of the first transmitting antenna 321 and the antenna aperture of the beam scanning antenna 31 are distributed along the pitch direction Y; as Figure 5 shown, in the pitch direction Y, the distance between the antenna aperture of the first transmitting antenna 321 and the antenna aperture of the beam scanning antenna 31 is L1, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L1 ≤ λ / 2.

[0117] In this embodiment, if L1 > λ / 2, there will be a grating lobe effect, that is, the multi-valuedness of the detection angle appears, thus affecting the radar scanning result. Therefore, L1 ≤ λ / 2, which reduces the risk of the grating lobe effect during the radar scanning process, and further improves the accuracy and reliability of the radar scanning result. Preferably, L1 = λ / 2 to increase the installation space of the first transmitting antenna 321 and the beam scanning antenna 31, and further reduce the installation difficulty.

[0118] In addition, in this embodiment, the antenna apertures of the first transmitting antenna 321 and the beam scanning antenna 31 are distributed along the pitch direction Y. When the signal emitted by the first transmitting antenna 321 is reflected by the target and returns to the receiving antenna 33, as Figure 6 shown, the receiving antenna 33 can generate a third type of antenna aperture 3e. The third type of antenna aperture 3e and the first type of antenna aperture 3c and the second type of antenna aperture 3d are distributed along the pitch direction Y, so as to facilitate the signal processing module 2 to judge and calculate parameters such as the angle, distance, and size of the target in the pitch direction Y, so as to improve the accuracy of the flight direction or avoidance direction of the UAV.

[0119] In another embodiment, the number of transmitting antennas 32 is at least two, that is, as Figure 2 、 Figure 3 and Figure 5 shown, the transmitting antenna 32 at least includes the first transmitting antenna 321 and the second transmitting antenna 322. The first transmitting antenna 321 and the second transmitting antenna 322 can both be connected to the second radio frequency chip 12, so that the first transmitting antenna 321 and the second transmitting antenna 322 are in parallel, thereby improving the directivity of the beam; or, the first transmitting antenna 321 is connected to the second radio frequency chip 12, the radio frequency module 1 further includes a fourth radio frequency chip 14, and the second transmitting antenna 322 is connected to the fourth radio frequency chip 14 to increase the width of the beam.

[0120] Among them, when the first transmitting antenna 321 is connected to the second radio frequency chip 12 and the second transmitting antenna 322 is connected to the fourth radio frequency chip 14, as Figure 5As shown, along the pitch direction Y, the second transmitting antenna 322 is located on the side of the first transmitting antenna 321 away from the beam scanning antenna 31; in the pitch direction Y, the distance between the antenna aperture of the second transmitting antenna 322 and the antenna aperture of the first transmitting antenna 321 is L2, and L2 ≤ λ / 2; in the azimuth direction X, the distance between the antenna aperture of the second transmitting antenna 322 and the antenna aperture of the first transmitting antenna 321 is L3, and L3 ≤ λ / 2.

[0121] In this embodiment, the antenna aperture of the first transmitting antenna 321 is the third output antenna aperture 321a, and the antenna aperture of the second transmitting antenna 322 is the fourth output antenna aperture 322a. The third output antenna aperture 321a and the fourth output antenna aperture 322a are distributed along the pitch direction Y. When the fourth radio frequency chip 14 transmits a signal through the second transmitting antenna 322, as Figure 6 shown, the receiving antenna 33 receives the reflected signal and forms a fourth type of antenna aperture 3f. The fourth type of antenna aperture 3f and the first type of antenna aperture 3c, the second type of antenna aperture 3d, and the third type of antenna aperture 3e are distributed along the pitch direction Y. Then, when the number of targets in the pitch direction Y does not exceed two, the signal processing module 2 can calculate the number of targets in the pitch direction Y to improve the accuracy and reliability of the radar and the UAV in target recognition.

[0122] Among them, if L2 > λ / 2 and L3 > λ / 2, there will be a grating lobe effect, that is, the multi-valuedness of the detection angle appears, which will affect the radar scanning result. Therefore, L2 ≤ λ / 2 and L3 ≤ λ / 2 reduce the risk of the grating lobe effect in the radar scanning process, and then improve the accuracy and reliability of the radar scanning result. Preferably, L2 = λ / 2 and L3 = λ / 2 to increase the installation space of the first transmitting antenna 321 and the second transmitting antenna 322, and then reduce the installation difficulty.

[0123] In addition, the transmitting antenna 32 may further include a third transmitting antenna 32, a fourth transmitting antenna 32, or even more distributed along the pitch direction to facilitate increasing the number of targets that the radar can identify in the pitch direction Y. Specifically, in the pitch direction Y, if the number of targets that the radar can identify is N1, then the total number of the transmitting antenna 32 and the beam scanning antenna 31 in the pitch direction Y needs to be greater than N1.

[0124] As Figure 3 and Figure 7As shown, the receiving antenna 33 further includes a third receiving antenna 333, and the third receiving antenna 333 is connected to the RF module 1. Specifically, the third receiving antenna 333 can be connected to the first RF chip 11, the second RF chip 12, the third RF chip 13, or the fourth RF chip 14. The antenna apertures of the first receiving antenna 331, the second receiving antenna 332, and the third receiving antenna 333 are arranged along the azimuth direction X.

[0125] In this embodiment, the first receiving antenna 331, the second receiving antenna 332, and the third receiving antenna 333 are distributed along the azimuth direction X. During the process of the first receiving antenna 331, the second receiving antenna 332, and the third receiving antenna 333 receiving signals, as Figure 5 shown, the first receiving antenna 331 generates a first input antenna aperture 34, the second receiving antenna 332 generates a second input antenna aperture 35, the third receiving antenna 333 generates a third input antenna aperture 36, and the first input antenna aperture 34, the second input antenna aperture 35, and the third input antenna aperture 36 are distributed along the azimuth direction X, enabling the signal processing module 2 to calculate that the number of targets in the azimuth direction X is one or two, so as to improve the accuracy and reliability of the radar and the UAV in target recognition.

[0126] When the number of receiving antennas 33 is n, the maximum number of targets that the radar can identify in the azimuth direction X is n - 1. Therefore, the more the number of receiving antennas 33, the more accurate the scanning calculation result of the radar.

[0127] In this embodiment, according to the number of RF chips, this application embodiment sets one beam scanning antenna 31, two transmitting antennas 32, and eight receiving antennas 33. As Figure 2 shown, the first RF chip 11 includes a first output port 111, a second output port 112, a first input port 113, and a second input port 114. The second RF chip 12 includes a third output port 121, a fourth output port 122, a third input port 123, and a fourth input port 124. The third RF chip 13 includes a fifth output port 131, a sixth output port 132, a fifth input port 133, and a sixth input port 134. The fourth RF chip 14 includes a seventh output port 141, an eighth output port 142, a seventh input port 143, and an eighth input port 144. The first output port 111 is respectively connected to the third output port 121, the fifth output port 131, and the seventh output port 141 through a power divider 15 to ensure the consistency of the output signal power of the four RF chips. As Figure 2 、 Figure 3 and Figure 7As shown, the second output port 112 and the sixth output port 132 are respectively connected to the beam scanning antenna 31. The first transmitting antenna 321 is connected to the fourth output port 122. The second transmitting antenna 322 is connected to the eighth output port 142. The first receiving antenna 331 is connected to the first input port 113. The second receiving antenna 332 is connected to the second input port 114. The third receiving antenna 333 is connected to the fifth input port 133. The fourth receiving antenna 334 is connected to the sixth input port 134. The fifth receiving antenna 335 is connected to the third input port 123. The sixth receiving antenna 336 is connected to the fourth input port 124. The seventh receiving antenna 337 is connected to the seventh input port 143. The eighth receiving antenna 338 is connected to the eighth input port 144.

[0128] When the first radio frequency chip 11 transmits signals through the second output port 112 and the beam scanning antenna 31, the radar is in the first sub-scanning mode. As Figure 5 shown, the beam scanning antenna 31 forms the first output antenna aperture 316. After the receiving antenna 33 receives the signal reflected by the target, it forms the first input antenna aperture 34, the second input antenna aperture 35, the third input antenna aperture 36, the fourth input antenna aperture 37, the fifth input antenna aperture 38, the sixth input antenna aperture 39, the seventh input antenna aperture 3a, and the eighth input antenna aperture 3b that are distributed along the azimuth direction X. As Figure 6 shown, the eight antenna apertures at this time are collectively referred to as the first type of antenna aperture 3c.

[0129] When the third radio frequency chip 13 transmits signals through the sixth output port 132 and the beam scanning antenna 31, the radar is in the second sub-scanning mode. As Figure 5 shown, the beam scanning antenna 31 forms the second output antenna aperture 317. After the receiving antenna 33 receives the signal reflected by the target, it forms the first input antenna aperture 34, the second input antenna aperture 35, the third input antenna aperture 36, the fourth input antenna aperture 37, the fifth input antenna aperture 38, the sixth input antenna aperture 39, the seventh input antenna aperture 3a, and the eighth input antenna aperture 3b that are distributed along the azimuth direction X. As Figure 6 shown, the eight antenna apertures at this time are collectively referred to as the second type of antenna aperture 3d. The second type of antenna aperture 3d and the first type of antenna aperture 3c are distributed along the azimuth direction X and have an overlapping part.

[0130] When the second radio frequency chip 12 transmits signals through the fourth output port 122 and the first transmitting antenna 321, the radar is in the first scanning mode. As Figure 5As shown, the first transmitting antenna 321 forms a third output antenna aperture 321a. After the receiving antenna 33 receives the signal reflected by the target, it forms a first input antenna aperture 34, a second input antenna aperture 35, a third input antenna aperture 36, a fourth input antenna aperture 37, a fifth input antenna aperture 38, a sixth input antenna aperture 39, a seventh input antenna aperture 3a, and an eighth input antenna aperture 3b that are distributed along the azimuth direction X, as Figure 6 shown. At this time, the eight antenna apertures are collectively referred to as the third type of antenna aperture 3e. The third type of antenna aperture 3e and the first type of antenna aperture 3c are distributed along the pitch direction Y.

[0131] When the fourth radio frequency chip 14 transmits a signal through the eighth output port 142 and the second transmitting antenna 322, the radar is in the first scanning mode, as Figure 5 shown. The second transmitting antenna 322 forms a fourth output antenna aperture 322a. After the receiving antenna 33 receives the signal reflected by the target, it forms a first input antenna aperture 34, a second input antenna aperture 35, a third input antenna aperture 36, a fourth input antenna aperture 37, a fifth input antenna aperture 38, a sixth input antenna aperture 39, a seventh input antenna aperture 3a, and an eighth input antenna aperture 3b that are distributed along the azimuth direction X, as Figure 6 shown. At this time, the eight antenna apertures are collectively referred to as the fourth type of antenna aperture 3f. The fourth type of antenna aperture 3f, the third type of antenna aperture 3e, and the first type of antenna aperture 3c are distributed along the pitch direction Y.

[0132] Among them, as Figure 5 shown, in the azimuth direction X, the distance L5 between the first input antenna aperture 34 and the second output antenna aperture 317 is λ, the distance L6 between the third output antenna aperture 321a and the fourth input antenna aperture 37 is λ, and the distance L7 between the fourth output antenna aperture 322a and the fifth input antenna aperture is λ, so as to increase the installation space of the beam scanning antenna 31, the transmitting antenna 32, and the receiving antenna 33.

[0133] In addition, the signal processing module 2 can output and input signals simultaneously to improve the signal processing efficiency. The signal processing module 2 can also output and input signals in different time periods to reduce the interference between signals.

[0134] The user can manually control one of the first radio frequency chip 11, the second radio frequency chip 12, the third radio frequency chip 13, and the fourth radio frequency chip 14 to transmit a signal, and / or, the first radio frequency chip 11, the second radio frequency chip 12, the third radio frequency chip 13, and the fourth radio frequency chip 14 can alternately transmit signals according to a preset program.

[0135] In summary, in this embodiment, by providing the first radio frequency chip 11, the third radio frequency chip 13, and the beam scanning antenna 31, the radar can scan the target through azimuth beam scanning, thereby enhancing the scanning intensity of the radar at the scanning edge in the azimuth direction X, that is, increasing the gain of the radar's scanning beam at azimuth angles of ±50°. At the same time, compared with fixed beam scanning, the azimuth beam is narrower, enabling the radar to have better beam directivity when in the second scanning mode. By providing a plurality of receiving antennas 33 distributed along the azimuth direction X, the radar can scan and calculate the number of targets in the azimuth direction X. By providing the first transmitting antenna 321 and the second transmitting antenna 322 distributed along the pitch direction Y, the radar can scan and calculate the number of targets in the pitch direction Y, so as to improve the accuracy of radar scanning.

[0136] The foregoing is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A radar, characterized in that, The radar includes: a radio frequency module (1), and the radio frequency module (1) includes a first radio frequency chip (11) and a second radio frequency chip (12); a signal processing module (2), and the signal processing module (2) is connected to the radio frequency module (1); an antenna module (3), and the antenna module (3) includes a beam scanning antenna (31), a transmitting antenna (32), and a receiving antenna (33). At least one of the transmitting antenna (32) and the beam scanning antenna (31) is configured to transmit a signal to a target, and the receiving antenna (33) is configured to receive a signal reflected by the target; the beam scanning antenna (31) includes a phase shifter network (311), a first radio frequency antenna (312), and a second radio frequency antenna (313). The first radio frequency chip (11) is connected to the first radio frequency antenna (312) and the second radio frequency antenna (313) respectively through the phase shifter network (311). The transmitting antenna (32) is connected to the second radio frequency chip (12). The receiving antenna (33) includes a first receiving antenna (331) and a second receiving antenna (332), and the first receiving antenna (331) and the second receiving antenna (332) are respectively connected to the radio frequency module (1); the second radio frequency chip (12) is configured to transmit a signal to the target through the transmitting antenna (32); the first radio frequency chip (11) is configured to transmit a signal to the target through the beam scanning antenna (31).

2. The radar according to claim 1, characterized in that, The radio frequency module (1) further includes a third radio frequency chip (13), and the third radio frequency chip (13) is connected to the first radio frequency antenna (312) and the second radio frequency antenna (313) respectively through the phase shifter network (311). The third radio frequency chip (13) is configured to transmit a signal to the target through the beam scanning antenna (31).

3. The radar according to claim 2, wherein The phase shifter network (311) includes a 3dB coupler (311a) and a cross-coupler (311b). The 3dB coupler (311a) is connected to the cross-coupler (311b), and the first radio frequency chip (11) and the third radio frequency chip (13) are respectively connected to the 3dB coupler (311a); the beam scanning antenna (31) further includes a third radio frequency antenna (314) and a fourth radio frequency antenna (315), and the first radio frequency antenna (312), the second radio frequency antenna (313), the third radio frequency antenna (314), and the fourth radio frequency antenna (315) are respectively connected to the cross-coupler (311b).

4. The radar according to claim 1, characterized in that, The transmitting antenna (32) includes a first transmitting antenna (321), and the first transmitting antenna (321) is connected to the second radio frequency chip (12). The antenna aperture of the first transmitting antenna (321) is distributed along the pitch direction (Y) with the antenna aperture of the beam scanning antenna (31); In the pitch direction (Y), the distance between the antenna aperture of the first transmitting antenna (321) and the antenna aperture of the beam scanning antenna (31) is L1, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L1 ≤ λ / 2.

5. The radar according to claim 4, characterized in that, The transmitting antenna (32) further includes a second transmitting antenna (322), and the second transmitting antenna (322) is connected to the second radio frequency chip (12).

6. The radar according to claim 5, characterized in that, The radio frequency module (1) further includes a fourth radio frequency chip (14), and the second transmitting antenna (322) is connected to the fourth radio frequency chip (14).

7. The radar according to claim 6, characterized in that, When the second transmitting antenna (322) is connected to the fourth radio frequency chip (14), along the pitch direction (Y), the second transmitting antenna (322) is located on the side of the first transmitting antenna (321) away from the beam scanning antenna (31). In the pitch direction (Y), the distance between the antenna aperture of the second transmitting antenna (322) and the antenna aperture of the first transmitting antenna (321) is L2, then L2 ≤ λ / 2. In the azimuth direction (X), the distance between the antenna aperture of the second transmitting antenna (322) and the antenna aperture of the first transmitting antenna (321) is L3, then L3 ≤ λ / 2.

8. The radar according to any one of claims 1 to 7, characterized in that, When the first radio frequency chip (11) transmits a signal, the antenna aperture of the beam scanning antenna (31) is at a first position, and when the third radio frequency chip (13) transmits a signal, the antenna aperture of the beam scanning antenna (31) is at a second position, and the first position and the second position are distributed along the azimuth direction (X). Along the azimuth direction (X), the distance between the first position and the second position is L4, and the wavelength of the electromagnetic wave emitted by the radar is λ, then L4 ≤ λ / 2.

9. The radar according to any one of claims 1 to 7, characterized in that The receiving antenna (33) further includes a third receiving antenna (333), the third receiving antenna (333) is connected to the first radio frequency chip (11), the third radio frequency chip (13) or the second radio frequency chip (12), and the antenna apertures of the first receiving antenna (331), the second receiving antenna (332) and the third receiving antenna (333) are arranged along the azimuth direction (X).

10. A drone, characterized in that, The unmanned aerial vehicle includes: A fuselage; The radar according to any one of claims 1 to 9, and the radar is installed on the fuselage; A power supply module (4), the power supply module (4) is installed on the fuselage, and the power supply module (4) is connected to the radio frequency module (1) and the signal processing module (2).

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