MOBILE OBJECT AND ANTENNA AUTOMATIC ALIGNMENT METHOD AND SYSTEM THEREOF

• US 20200136695A1
• Filed: 12/30/2019
• Published: 04/30/2020
• Est. Priority Date: 12/31/2014
• Status: Active Grant

• Current Assignee: SZ DJI Technology Co., Ltd. (d/b/a DJI) (iFlight Technology Company Limited)
• Original Assignee: SZ DJI Technology Co., Ltd. (d/b/a DJI) (iFlight Technology Company Limited)
• Inventors: HU, Meng, XIE, Peng, ZHAO, Tao, WEI, Jianping
• Granted Patent: US 11,057,087 B2
• Time in Patent Office: Days
• CPC Class Codes: B64U 2201/00 UAVs characterised by their flight controls
• CPC Class Codes: B64U 2201/20 Remote controls
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04B 7/0802 using antenna selection H04B7/0868 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04W 4/21 for social networking applications
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

A UAV system includes a remote controller including two first antennas and a UAV including two second antennas arranged at two landing stands of the UAV, respectively. The two first antennas and the two second antennas are configured to establish a 2×2 MIMO communication link. The remote controller is configured to transmit current terminal position information of the remote controller to the UAV via the 2×2 MIMO communication link. The UAV determines current remote controller relative position information of the remote controller relative to the UAV according to the current terminal position information and current UAV position information acquired via a position sensor, and controls communication between the UAV and the remote controller according to the current remote controller relative position information.

Claims

1. A multi-rotor unmanned aerial vehicle (UAV) system comprising:

a remote controller including;

two first wireless antennas;

a terminal positioning sensor configured to sense current terminal position information of the remote controller; and

a terminal controller coupled to the two first wireless antennas and the terminal positioning sensor, and configured to receive the current terminal position information from the terminal positioning sensor and transmit the current terminal position information via the two first wireless antennas; and

a multi-rotor UAV comprising;

two landing stands;

two second wireless antennas arranged at the two landing stands, respectively, the two second wireless antennas being configured to establish a 2×

2 multi-input-multi-output (MIMO) communication link with the two first wireless antennas, and to receive the current terminal position information through the 2×

2 MIMO communication link;

a position sensor configured to acquire current UAV position information; and

a UAV controller coupled to the two second wireless antennas and configured to;

receive the current terminal position information from the two second wireless antennas;

receive the current UAV position information;

determine current remote controller relative position information of the remote controller relative to the UAV according to the current terminal position information and the current UAV position information; and

control communication between the UAV and the remote controller according to the current remote controller relative position information.

2. The UAV system of claim 1, wherein the 2×

2 MIMO communication link is a visual range point-to-point communication link.

3. The UAV system of claim 1, wherein each of the two first wireless antennas and the two second wireless antennas includes a WiFi antenna, a worldwide interoperability for microwave access (WiMAX) antenna, or a coded orthogonal frequency-division multiplexing (COFDM) antenna.

4. The UAV system of claim 1, wherein the UAV further includes two spare wireless antennas not currently used in the communication between the UAV and the remote controller.

5. The UAV system of claim 4, wherein the two second wireless antennas and the two spare wireless antennas are of a same type.

6. The UAV system of claim 4, wherein:

the UAV includes four wireless antennas; and

the UAV controller is further configured to select two of the four wireless antennas as the second wireless antennas, unselected two of the four wireless antennas being the two spare wireless antennas.

7. The UAV system of claim 6, wherein the controller is further configured to select the two of the four wireless antennas by:

determining whether the current remote controller relative position information satisfies a switching criterion; and

selecting the two of the four wireless antennas to establish the 2×

2 MIMO communication link in accordance with the switching criterion.

8. The UAV system of claim 1, wherein:

the UAV further includes an attitude sensor configured to acquire current UAV attitude information; and

the UAV controller is further configured to;

receive the current UAV attitude information;

determine current antenna relative position information of the two second wireless antennas relative to the UAV based on the current UAV attitude information and preset antenna attitude information of the two second wireless antennas relative to the UAV; and

control the communication between the UAV and the remote controller according to the current remote controller relative position information and the current antenna relative position information.

9. The UAV system of claim 8, wherein:

the UAV includes four wireless antennas; and

the UAV controller is further configured to select two of the four wireless antennas as the second wireless antennas, unselected two of the four wireless antennas being two spare wireless antennas not currently used in the communication between the UAV and the remote controller.

10. The UAV system of claim 9, wherein the UAV controller is further configured to select the two of the four wireless antennas by:

determining whether the current remote controller relative position information and the current antenna relative position information satisfy a switching criterion; and

selecting the two of the four wireless antennas to establish the 2×

2 MIMO communication link in accordance with the switching criterion.

11. The UAV system of claim 10, wherein the UAV controller is further configured to determine whether the current remote controller relative position information and the current antenna relative position information satisfy the switching criterion by:

constructing a plurality of position ranges in accordance with the current antenna relative position information; and

determining whether at least one of the plurality of position ranges covers the current remote controller relative position information.

12. The UAV system of claim 11, wherein the UAV controller is further configured to select the two of the four wireless antennas that correspond to one of the at least one of the position ranges that covers the current remote controller position information.

13. The UAV system of claim 11, wherein the UAV controller is further configured to construct the position ranges by constructing a coordinate range, one end point of the coordinate range corresponding to current position information of one of the four wireless antennas relative to the UAV and another end point of the coordinate range corresponding to current position information of another one of the four wireless antennas relative to the UAV.

14. A communication method comprising:

receiving current terminal position information from a remote controller, the current terminal position information being sensed by a terminal positioning sensor of the remote controller, transmitted via two first wireless antennas of the remote controller, and received by two second wireless antennas of a multi-rotor UAV through a 2×

2 multi-input-multi-output (MIMO) communication link established between the two first wireless antennas and the two second wireless antennas, and the two second wireless antennas being arranged at two landing stands of the UAV, respectively;

receiving current UAV position information acquired by a position sensor of the UAV;

determining current remote controller relative position information of the remote controller relative to the UAV according to the current terminal position information and the current UAV position information; and

controlling communication between the UAV and the remote controller according to the current remote controller relative position information.

15. The method of claim 14, wherein the 2×

2 MIMO communication link is a visual range point-to-point communication link.

16. The method of claim 14, further comprising:

receiving current UAV attitude information acquired by an attitude sensor of the UAV; and

determining current antenna relative position information of the two second wireless antennas relative to the UAV based on the current UAV attitude information and preset antenna attitude information of the two second wireless antennas relative to the UAV;

wherein controlling the communication between the UAV and the remote controller includes controlling the communication according to the current remote controller relative position information and the current antenna relative position information.

17. The method of claim 16, further comprising:

selecting two of four wireless antennas of the UAV as the second wireless antennas;

wherein unselected two of the four wireless antennas are two spare wireless antennas not currently used in the communication between the UAV and the remote controller.

18. The method of claim 17, wherein selecting the two of the four wireless antennas includes:

determining whether the current remote controller relative position information and the current antenna relative position information satisfy a switching criterion; and

selecting the two of the four wireless antennas to establish the 2×

2 MIMO communication link in accordance with the switching criterion.

19. The method of claim 18, wherein determining whether the current remote controller relative position information and the current antenna relative position information satisfy the switching criterion includes:

constructing a plurality of position ranges in accordance with the current antenna relative position information; and

determining whether at least one of the plurality of position ranges covers the current remote controller relative position information.

20. The method of claim 19, wherein constructing the position ranges includes constructing a coordinate range, one end point of the coordinate range corresponding to current position information of one of the four wireless antennas relative to the UAV and another end point of the coordinate range corresponding to current position information of another one of the four wireless antennas relative to the UAV.