Cooperative clustering for enhancing MU-massive-MISO-based UAV communication

Patent metadata

Field	Value
Publication number	US-10312993-B2
Application number	US-201615337346-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Oct 30, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

Methods, apparatuses, and systems for organizing data delivering unmanned aerial vehicles (UAVs) are provided. Inter-cluster coordinators can organize data delivering unmanned aerial vehicle base stations (UAV-BSs). Various beamforming techniques (e.g., LZFBF and ZFBF) can be incorporated, and the inter-cluster coordinator can operate on a base station that serves as a controlling network node.

First claim

What is claimed is:

1. A method for identifying optimum hovering locations for unmanned aerial vehicle base stations (UAV-BSs) communications, the method comprising:
identifying user locations;
defining a hovering grid that includes the user locations;
determining an absolute value of directional cosine separation |Ω k,un | for each grid point, which is the separation between directional cosines between the uth user and the kth user of the nth UAV-BS;
detecting all grid points (y,z) with directional cosine separation |Ω k,un |=2/N t ×q and q≤N t −1, wherein N t is the number of antenna arrays for the nth UAV-BS and q is an integer;
calculating the distance from all grid points (y,z) to each user; and
assigning grid point (y,z) to the UAV-BSs (y n ,z n ) based on the minimum distance to their intended user.

2. The method of claim 1 , wherein the hovering grid is symmetric around two or more users.

3. The method of claim 1 , wherein the directional cosine separation for each grid point is determined by Ω k,un =cos Φ un −cos Φ kn , which is the separation between directional cosines between the uth user and the kth user of the nth UAV-BS.

4. The method of claim 1 , wherein the method is executed partially or entirely within one or more of the UAV-BSs.

5. The method of claim 1 , further comprising incorporating transmit (Tx) beamforming.

6. The method of claim 1 , further comprising incorporating linear zero-force (LZFBF) beamforming.

7. The method of claim 1 , wherein the method does not include sending channel state information.

8. The method of claim 1 , wherein if no grid points are found in the detecting all grid points (y,z) with directional cosine separation |Ω k,un |=2/N t ×q and q≤N t −1, the method further comprises selecting grid points with directional cosine separation closest to an integer multiple of 2/N t that can satisfy the constraints in

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9. The method of claim 1 , wherein the method further comprises incorporating linear single user beamforming (LSUBF).

10. The method of claim 1 , wherein the method further comprises incorporating zero-forcing beamforming (ZFBF).

11. The method of claim 1 , wherein the method includes millimeter wave communication technology.

12. An inter-cluster coordinator for identifying optimum hovering locations for unmanned aerial vehicle base stations (UAV-BSs) comprising a processor, volatile and non-volatile memory, antennas suitable for communicating with the unmanned aerial vehicle base stations (UAV-BSs) and a non-transitory machine-readable medium with computer executable instructions stored thereon that when executed by a processor perform the method of:
identifying user locations;
defining a hovering grid that includes the user locations;
determining an absolute value of directional cosine separation |Ω k,un | for each grid point, which is the separation between directional cosines between the uth user and the kth user of the nth UAV-BS;
detecting all grid points (y,z) with directional cosine separation |Ω k,un |=2/N t ×q and q≤N t −1, wherein N t is the number of uniform linear antenna arrays for the nth UAV-BS and q is an integer;
calculating the distance from all grid points (y,z) to each user; and
assigning grid point (y,z) to the UAV-BSs (y n ,z n ) based on the minimum distance to their intended user.

13. The inter-cluster coordinator of claim 12 , wherein the inter-cluster coordinator is a UAV-BS.

14. The inter-cluster coordinator of claim 12 , wherein the method further comprises transmit (Tx) beamforming.

15. The inter-cluster coordinator of claim 12 , wherein the method further comprises linear zero-force (LZFBF) beamforming.

16. The inter-cluster coordinator of claim 12 , wherein the method does not include sending channel state information.

17. The inter-cluster coordinator of claim 12 , wherein the method includes incorporating millimeter wave communication technology.

Assignees

• Rupasinghe Nadisanka
• Guvenc Ismail
• Mohamed Ahmed Salah Ibrahim
• The Florida International Univ Board Of Trustees

Inventors

• Rupasinghe Nadisanka
• Guvenc Ismail
• Mohamed Ahmed Salah Ibrahim

Classifications

• H04B7/18506 Primary

  Communications with or from aircraft, i.e. aeronautical mobile service · CPC title

• H04B7/0452

  Multi-user MIMO systems · CPC title

• B64U2201/102

  adapted for flying in formations · CPC title

• B64U2101/20

  for use as communications relays, e.g. high-altitude platforms · CPC title

• H04B7/0617

  for beam forming · CPC title