Location estimation system, location estimation method, and base station control device

Patent metadata

Field	Value
Publication number	US-10285015-B2
Application number	US-201715650654-A
Country	US
Kind code	B2
Filing date	Jul 14, 2017
Priority date	Sep 28, 2016
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A location estimation system for estimating a location of a wireless communication terminal, the location estimation system including first to M-th wireless communication devices and a control device, wherein i-th wireless communication device includes communication circuitry, which in operation, receives a signal transmitted from the wireless communication terminal using beams in Ni directions, and control circuitry, which in operation, calculates Ni reception qualities corresponding to the beams in the Ni directions, respectively, and wherein the control device includes control circuitry, which in operation, estimates i-th arrival direction of the signal received by the i-th wireless communication device by comparing the Ni reception qualities with the radiation angle characteristics of the beams in the Ni directions, and estimates the location of the wireless communication terminal based on the first to the M-th arrival directions estimated and locations of the first to the M-th wireless communication devices.

First claim

What is claimed is:

1. A location estimation system for estimating a location of a wireless communication terminal, the location estimation system including first to M-th wireless communication devices and a control device, M being an integer equal to or more than two, wherein:
each i-th wireless communication device, for all integers i between 1 to M, includes:
communication circuitry, which in operation, receives a signal transmitted from the wireless communication terminal using beams in Ni directions, Ni being an integer equal to or more than two, and
control circuitry, which in operation, calculates Ni reception qualities corresponding to the beams in the Ni directions, respectively, and wherein

the control device includes:
storage circuitry, which in operation, stores radiation angle characteristics of the beams in the Ni directions for each of the first to M-th wireless communication devices and
control circuitry, which in operation, for all integers i between 1 and M: estimates an i-th arrival direction vector ai of the signal received by the i-th wireless communication device by comparing the Ni reception qualities obtained from the i-th wireless communication device with the radiation angle characteristics of the beams in the Ni directions, and determines, for all i of at least the first to M-th wireless communication devices:
an orientation transformation matrix Mi corresponding to an orientation of an array antenna of the communication device,
a vector ni=Mi ai, and
a line Li that passes through a location of the i-th wireless communication device and is parallel to the vector ni;

determines, for all pairs (i, j) of wireless communication devices with 1≤i≤M and 1≤j≤M a point Pi,j which is a closest point to the line Lj among points on the line Li, and
estimates the location of the wireless communication terminal from the center of mass of all points Pi,j with 1≤i≤M and 1≤j≤M.

2. The location estimation system according to claim 1 , wherein
the control circuitry of the i-th wireless communication device communicates with the wireless communication terminal using the beam corresponding to a best reception quality among of the Ni reception qualities.

3. The location estimation system according to claim 1 , wherein
the control circuitry of the control device estimates the i-th arrival direction by performing pattern matching between a reception quality vector and an arrival direction model, the reception quality vector representing the Ni reception qualities, the arrival direction model representing the radiation angle characteristics of the beams in the Ni directions.

4. The location estimation system according to claim 1 , wherein
the control circuitry of the control device transforms a coordinate system used for estimating the i-th arrival direction to a coordinate system in which the location of the i-th wireless communication device is to be defined.

5. A location estimation method for estimating a location of a wireless communication terminal in a system including at least first to M-th wireless communication devices, M being an integer equal to or more than two, the location estimation method comprising:
receiving, for all i with 1≤i≤M, with the i-th wireless communication device, a signal transmitted from the wireless communication terminal using beams in Ni directions, Ni being an integer equal to or more than two;
calculating Ni reception qualities corresponding to the beams in the Ni directions, respectively;
estimating, for all i with 1≤i≤M, an i-th arrival direction vector ai of the signal received by the i-th wireless communication device by comparing the Ni reception qualities with radiation angle characteristics of the beams in the Ni directions;
determining, for all i of at least first to M-th wireless communication devices:
an orientation transformation matrix Mi corresponding to an orientation of an array antenna of the communication device,
a vector ni=Mi ai,
a line Li which is the line that passes through a location of the i-th wireless communication device and is parallel to the vector ni;

determining, for all pairs (i,j) of wireless communication devices with 1≤i≤M and 1≤j≤M a point Pi,j which is the closest point to the line Lj among points on the line Li, and
estimating the location of the wireless communication terminal from a center of mass of all points Pi,j with 1≤i≤M and 1≤j≤M.

6. A base station control device that is connected to first to M-th wireless communication devices, M being an integer equal to or more than two, and estimates a location of a wireless communication terminal, the base station control device comprising:
an input-and-output terminal that receives input of Ni reception qualities corresponding to beams in Ni directions, respectively, Ni being an integer equal to or more than two, the Ni reception qualities being calculated by receiving a signal transmitted from the wireless communication terminal with i-th wireless communication device using the beams in the Ni directions, i being an integer between 1 to M;
storage circuitry, which in operation, stores radiation angle characteristics of the beams in the Ni directions for each of the first to M-th wireless communication devices; and
control circuitry, which in operation:
estimates i-th arrival direction vector ai of the signal received by the i-th wireless communication device by comparing the Ni reception qualities obtained from the i-th wireless communication device with the radiation angle characteristics of the beams in the Ni directions,
determines, for all i of at least first to M-th wireless communication devices:
an orientation transformation matrix Mi corresponding to an orientation of an array antenna of the communication device,
a vector ni=Mi ai, and
a line Li that passes through a location of the i-th wireless communication device and is parallel to the vector ni,

determines, for all pairs (i,j) of wireless communication devices APi, APj with 1≤i≤M and 1≤j≤M a point Pi,j which is the closest point to the line Lj among points on the line Li, and
estimates the location of the wireless communication terminal from a center of mass of all points Pi,j with 1≤i≤M and 1≤j≤M.

Assignees

• Panasonic Ip Corp America

Inventors

• Shirakata Naganori
• Takahashi Hiroshi
• Urushihara Tomoya
• Morita Junichi

Classifications

• G01S5/0036

  of measured values, i.e. measurement on mobile and position calculation on base station · CPC title

• G01S5/04 Primary

  Position of source determined by a plurality of spaced direction-finders · CPC title

• G01S5/12

  by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial · CPC title

• H04B7/0617

  for beam forming · CPC title

• H04W4/025 Primary

  using location based information parameters · CPC title