Indoor event detection system and method

Patent metadata

Field	Value
Publication number	US-11113363-B2
Application number	US-201816202150-A
Country	US
Kind code	B2
Filing date	Nov 28, 2018
Priority date	Nov 28, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

An indoor event detection system includes a transmitter and a receiver. The transmitter includes a first antenna, and the receiver includes a second antenna, a processor and a memory. The receiver communicates with the transmitter based on a line of sight link between the transmitter and the receiver covering an area to be detected in the indoor space. The processor detects whether an event associated to the indoor space is occurred by obtaining a current CSI from the probe signal, obtaining an amplitude matrix by extracting a plurality amplitudes of a plurality of sub-carriers from the current CSI, applying a statistical operation on the amplitude matrix to obtain a statistical matrix, obtaining a plurality of eigenvalues from the statistical matrix, obtaining a current eigenvalue statistical value according to the plurality of eigenvalues; and determining whether the current eigenvalue statistical value is within the first eigenvalue range.

First claim

What is claimed is:

1. An indoor event detection system, comprising:
a transmitter disposed at a first position in an indoor space, including a first antenna having a transmitting direction; and
a receiver disposed at a second position in the indoor space, including:
a second antenna communicating with the transmitter based on a line of sight link between the transmitter and the receiver covering an area to be detected in the indoor space, wherein the transmitter is configured to send a probe signal toward the transmitting direction, and the receiver is configured to receive the probe signal;
a processor; and
a memory storing first event channel state information (CSI) and a first eigenvalue range obtained from the first event CSI;
wherein the processor is configured to detect whether an event associated to the indoor space is occurred by performing the following steps:
obtaining a current CSI from the probe signal;
obtaining an amplitude matrix by extracting a plurality amplitudes of a plurality of sub-carriers from the current CSI;
applying a statistical operation on the amplitude matrix to obtain a statistical matrix;
obtaining a plurality of eigenvalues from the statistical matrix;
obtaining a current eigenvalue statistical value according to the plurality of eigenvalues; and
determining whether the current eigenvalue statistical value is within the first eigenvalue range,
wherein when the current eigenvalue statistical value is within the first eigenvalue range, a first event associated with the indoor space is determined to be occurred,
wherein the statistical operation includes performing a covariance operation on the amplitude matrix to obtain a current covariance matrix as the statistical matrix,
wherein obtaining the plurality of eigenvalues from the statistical matrix includes:
obtaining a diagonal eigenvalue matrix from the current covariance matrix; and
sorting elements of the diagonal eigenvalue matrix, according to magnitudes of the elements, to obtain a sorted eigenvalue matrix, wherein elements of the sorted eigenvalue serve as the plurality of eigenvalues.

2. The indoor event detection system according to claim 1 , wherein obtaining a current eigenvalue statistical value according to the plurality of eigenvalues includes:
applying a simple or multiple linear regression on the plurality of eigenvalues to obtain at least one linear regression parameter as the current eigenvalue statistical value.

3. The indoor event detection system according to claim 1 , wherein obtaining a current eigenvalue statistical value according to the plurality of eigenvalues includes:
obtaining a plurality of weight values of the plurality of eigenvalues by respectively dividing the plurality of eigenvalues with a summation of the plurality of eigenvalues; and
taking one of the plurality of weight values with largest percentage among all of the plurality of weight values as the current eigenvalue statistical value.

4. The indoor event detection system according to claim 1 , wherein the memory further stores second event CSI and a second eigenvalue range obtained from the second event CSI, and the processor is further configured to determine whether the current eigenvalue statistical value is within the first eigenvalue range or the second eigenvalue range,
wherein when the current eigenvalue statistical value is within the second eigenvalue range, a second event associated with the indoor space is determined to be occurred.

5. An indoor event detection method, comprising:
arranging a transmitter at a first position in an indoor space, wherein the transmitter includes a first antenna having a transmitting direction;
arranging a receiver at a second position in the indoor space, wherein the receiver includes a second antenna communicating with the transmitter based on a line of sight link between the transmitter and the receiver covering an area to be detected in the indoor space, a processor and a memory storing first event channel state information (CSI) and a first eigenvalue range obtained from the first event CSI;
configuring the transmitter to send a probe signal toward the transmitting direction;
configuring the receiver to receive the probe signal;
configuring the processor to detect whether an event associated to the indoor space is occurred by performing the following steps:
obtaining a current CSI from the probe signal;
obtaining an amplitude matrix by extracting a plurality of amplitudes of a plurality of sub-carriers from the current CSI;
applying a statistical operation on the amplitude matrix to obtain a statistical matrix;
obtaining a plurality of eigenvalues from the statistical matrix;
obtaining a current eigenvalue statistical value according to the plurality of eigenvalues; and
determining whether the current eigenvalue statistical value is within the first eigenvalue range,
wherein when the current eigenvalue statistical value is within the first eigenvalue range, a first event associated with the indoor space is determined to be occurred,
wherein the statistical operation includes performing a covariance operation on the amplitude matrix to obtain a current covariance matrix as the statistical matrix,
wherein obtaining the plurality of eigenvalues from the statistical matrix includes:
obtaining a diagonal eigenvalue matrix from the current covariance matrix; and
sorting elements of the diagonal eigenvalue matrix, according to magnitudes of the elements, to obtain a sorted eigenvalue matrix, wherein elements of the sorted eigenvalue serve as the plurality of eigenvalues.

6. The indoor event detection method according to claim 5 , wherein obtaining a current eigenvalue statistical value according to the plurality of eigenvalues includes:
applying a simple or multiple linear regression on the plurality of eigenvalues to obtain at least one linear regression parameter at the current eigenvalue statistical value.

7. The indoor event detection method according to claim 5 , wherein obtaining a current eigenvalue statistical value according to the plurality of eigenvalues includes:
obtaining a plurality of weight values of the plurality of eigenvalues by respectively dividing the plurality of eigenvalues with a summation of the plurality of eigenvalues; and
taking one of the plurality of weight values with largest percentage among all of the plurality of weight values as the current eigenvalue statistical value.

8. The indoor event detection method according to claim 5 , wherein the memory further stores second event CSI and a second eigenvalue range obtained from the second event CSI, and the processor is further configured to determine whether the current eigenvalue statistical value is within the first eigenvalue range or the second eigenvalue range, wherein when the current eigenvalue statistical value is within the second eigenvalue range, a second event associated with the indoor space is determined to be occurred.

Assignees

• Wistron Neweb Corp

Inventors

• Wei Ya-Ping
• Chen Horen

Classifications

• G01S13/003

  Bistatic radar systems; Multistatic radar systems · CPC title

• G01S13/04 Primary

  Systems determining presence of a target (based on relative movement of target G01S13/56) · CPC title

• G06F17/18 Primary

  for evaluating statistical data {, e.g. average values, frequency distributions, probability functions, regression analysis (forecasting specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title

• G06F17/16

  Matrix or vector computation {, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization (matrix transposition G06F7/78)} · CPC title