CN112505624A - Positioning system based on environment backscattering - Google Patents

Positioning system based on environment backscattering Download PDF

Info

Publication number
CN112505624A
CN112505624A CN202011425053.XA CN202011425053A CN112505624A CN 112505624 A CN112505624 A CN 112505624A CN 202011425053 A CN202011425053 A CN 202011425053A CN 112505624 A CN112505624 A CN 112505624A
Authority
CN
China
Prior art keywords
signal
backscatter
receiver
direct link
arrival
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202011425053.XA
Other languages
Chinese (zh)
Other versions
CN112505624B (en
Inventor
梁应敞
朱贤明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
University of Electronic Science and Technology of China
Original Assignee
University of Electronic Science and Technology of China
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University of Electronic Science and Technology of China filed Critical University of Electronic Science and Technology of China
Priority to CN202011425053.XA priority Critical patent/CN112505624B/en
Publication of CN112505624A publication Critical patent/CN112505624A/en
Application granted granted Critical
Publication of CN112505624B publication Critical patent/CN112505624B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
    • G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Position Fixing By Use Of Radio Waves (AREA)

Abstract

The invention belongs to the technical field of wireless communication, and particularly relates to a positioning system based on environmental backscattering. The invention calculates the arrival angle of the signals through a spatial domain signal processing technology according to the fact that the signals received by a receiver comprise direct link signals from an environment radio frequency source and environment signals which are backscattered by a backscatter body, the calculation result comprises the arrival angles of the direct link signals and the backscatter signals, the arrival angles of the direct link signals and the backscatter signals are distinguished by utilizing the characteristic that the backscatter signals are subjected to twice fading compared with the direct link signals, and the coordinates of the backscatter body are calculated according to the arrival angles of the backscatter signals to realize positioning. The method is suitable for indoor plane positioning scenes such as logistics warehouses and the like, and the scheme is simple to implement and has high application value.

Description

Positioning system based on environment backscattering
Technical Field
The invention belongs to the technical field of wireless communication, and particularly relates to a positioning system based on environmental backscattering.
Background
With the coming of the 5G era, the internet of things will come to a rapid development stage, and future communication networks will bring huge traffic and huge connection numbers with the rapid growth of internet of things devices. In the current 5G era and even the new 6G vision in the future, efficient utilization of spectrum resources is one of effective means for solving the challenge of huge traffic and huge connection of the internet of things. The environment backscattering technology replaces a special radio frequency source of a traditional backscattering communication system with an environment radio frequency source, so that the cost for deploying the special radio frequency source can be reduced, the utilization rate of frequency spectrum resources is improved, and the positioning system has the potential of realizing high spectrum efficiency and low energy consumption.
In a practical application scene, the radio frequency source signal and the environmental backscatter signal generally come from different directions, and by utilizing the characteristic, the radio frequency source signal and the environmental backscatter signal can be distinguished in a space domain, so that the corresponding signal arrival direction can be obtained. In some application scenarios, the signal direction of the backward scatterer can be accurately estimated, and then the backward scatterer can be positioned.
Disclosure of Invention
The invention mainly provides a positioning system design based on an environment backscattering technology, and realizes the positioning of an environment backscattering body.
The invention uses a receiver to receive signals, the received signals generally comprise direct link signals from an environmental radio frequency source and environmental signals which are backscattered by a backscatter, the receiver calculates the arrival angle of the signals by a space domain signal processing technology, and the calculation result generally comprises two angles, namely the arrival angles of the direct link signals and the backscatter signals. The invention can distinguish the arrival angle of the direct link and the backscattering signal by utilizing the characteristic that the backscattering signal can experience twice fading compared with the direct link signal, and can solve the coordinate of the backscattering body with low cost and high efficiency through a system scheme after the arrival angle of the backscattering signal is obtained.
The technical scheme of the invention is as follows:
a positioning system based on environmental backscattering comprises a radio frequency source, a plurality of receivers with M antennas and a backscattering device, wherein M is more than or equal to 3; the receiver receives the direct link signal and the environmental signal which is backscattered by the backscattering device, the receiver respectively obtains the arrival angles of the direct link signal and the backscattering signal, and the coordinates of the backscattering device are obtained according to the arrival angles of the backscattering signal and the known position coordinates of the plurality of receivers.
The specific method for the receiver to respectively obtain the arrival angles of the direct link signal and the backscatter signal is as follows:
assume that the signal received by the receiver is:
y(t)＝yd(t)+yb(t)+ω(t)
wherein, yd(t) is the received direct link signal, yb(t) is the received backscatter signal, ω (t) is the noise subject to a circularly symmetric gaussian distribution; the arrival angles of the direct link signal and the backscatter signal are obtained through a DOA estimation algorithm, and the arrival angles of the direct link signal and the backscatter signal are distinguished according to the characteristic that the backscatter signal is subjected to fading twice compared with the direct link signal.
The specific method for obtaining the coordinates of the backscatter device is as follows:
suppose the position coordinates are (x)0,y0) The receiver obtains an angle of arrival of theta0In the position coordinate of (x)1,y1) The receiver obtains an angle of arrival of theta1Obtaining the coordinates of the backscatter means
Figure RE-GDA0002895465040000021
Comprises the following steps:
Figure RE-GDA0002895465040000022
Figure RE-GDA0002895465040000023
in the above scheme, for the case of using a plurality of receivers, and for the case of using one receiver, the coordinates of the backscatter device may be calculated according to the arrival angles of the backscatter signals obtained by the receiver at different position coordinates, specifically:
assume that the receiver is at position coordinate (x)0,y0) To obtain an angle of arrival of theta0Moving the receiver to a position coordinate (x)1,y1) To obtain an angle of arrival of theta1Obtaining the coordinates of the backscatter means
Figure RE-GDA0002895465040000024
Comprises the following steps:
Figure RE-GDA0002895465040000025
Figure RE-GDA0002895465040000026
the invention has the beneficial effects that: by utilizing the characteristic that the radio frequency source signal and the reflected signal in the environment backscattering communication system usually do not reach the receiver at the same angle, the arrival angle of the reflected signal is separately estimated, and then the specific position of the backscattering body is estimated. The scheme is suitable for indoor plane positioning scenes such as logistics warehouses, is simple to implement and has high application value.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention;
FIG. 2 is a schematic flow chart of the present invention;
FIG. 3 is a diagram illustrating a relationship between an estimation accuracy of an angle of arrival of a backscatter link and a signal-to-noise ratio of the backscatter link in simulation;
FIG. 4 is a schematic diagram of the results of a positioning simulation Monte Carlo experiment.
Detailed Description
The invention is described in detail below with reference to the figures and simulation examples.
As shown in FIG. 1, the positioning system of the present invention comprises an ambient radio frequency source, one or more receivers with M (M ≧ 3) antennas, and a backscatter. The environment radio frequency source does not need to be deployed independently, and nearby base stations and WiFi hotspots can be used as radio frequency signal sources. A single antenna may be deployed on the backscatter, or multiple antennas may be deployed. Each receiver device is provided with M receiving antennas, and if two or more receivers are used for receiving, the receivers are arranged at different known positions, and a plurality of arrival angles of the backscatter signals are calculated at the same time, so that the coordinates of the backscatter body are calculated. If one receiver is used for receiving, the receiver can be moved to a known position according to a fixed rule, signals received by multiple receivers are simulated through the moving process, and then the coordinates of the backscattering body are calculated.
Where h represents the channel parameters of the ambient rf source to the backscatter, f represents the channel parameters of the ambient rf source to the receiver, and g represents the channel parameters of the backscatter to the receiver.
In the invention:
transmitting radio frequency source signal by environment radio frequency source
Figure RE-GDA0002895465040000031
Where s (t) is the baseband signal of the ambient RF source with a transmission power of ps，fcIs the carrier frequency of the ambient radio source signal.
The bandpass form of the ambient radio frequency source signal received by the array element with the receiver serial number of 0 is:
Figure RE-GDA0002895465040000032
wherein f represents the channel parameter of the channel from the environmental radio frequency source to the receiver, and the numerical subscript thereof represents the antenna corresponding to the number of the receiver.
The receiving process is illustrated with a uniform linear array: the propagation delay of the array element numbered m with respect to the array element numbered 0 is
Figure RE-GDA0002895465040000041
Where c is the speed of light, d is the interval of array elements, theta is the plane angle between the signal arrival direction and the array element orientation, i.e. the signal incidence angle, and tau is the propagation delay of the array element numbered 1 relative to the array element numbered 0
The band-pass form of the environment radio frequency source signal received by the receiver with the serial number of m array elements is as follows:
Figure RE-GDA0002895465040000042
according to the practical application scenario, the following assumptions can be made:
1. the ambient radio frequency source is far away from the receiver and the incident wave isPlane wave, array element interval is small. Thus the channel parameter fmFor all M e [0, M-1]The same is true.
The bandwidth of s (t) is much smaller than the carrier frequency, so the time delay between array elements is negligible compared to the symbol interval. Thus, for all receiving elements, s (t) is the same at the same time, i.e. s (t) s (t- τ)m)
Thus, the signal arriving at the ambient rf source of each array element of the receiver can be written as:
Figure RE-GDA0002895465040000043
due to time delays, the signals arriving at each array element differ only in phase. The phase difference between the array element numbered m and the array element numbered 0 to the received environment radio frequency source signal is
Figure RE-GDA0002895465040000044
Wherein f iscIs the carrier frequency, tau, of the ambient radio source signalmThe propagation delay of the array element numbered m relative to the array element numbered 0.
The array element spacing d is set to half the wavelength of the carrier, i.e.
Figure RE-GDA0002895465040000045
λ is the carrier wavelength and the direction of arrival of the signal is θ, then
Figure RE-GDA0002895465040000046
Thus, it is possible to provide
Figure RE-GDA0002895465040000047
Order to
Figure RE-GDA0002895465040000048
Representing a phase shift of the direct signal received by the array element numbered m with respect to the direct signal of the array element numbered 0, then
Figure RE-GDA0002895465040000049
Wherein theta isdIs the direction of incidence of the ambient radio source signal (direct signal). Defining a direction vector as af(θd)＝[1,af,1(θd),...,af,M-1(θd)]TThen, the ambient rf source signals received by all array elements from the direct link are:
Figure RE-GDA0002895465040000051
the signal from the ambient radio source will reach the receiver after being reflected by the backscatter. The ambient radio source signal received by the back scatterer is:
Figure RE-GDA0002895465040000052
where h represents the channel parameter between the ambient radio source to the back scatterer.
The backscatter will modulate its own baseband signal c (t) to
Figure RE-GDA0002895465040000053
Up and reflected, with a reflection coefficient α, so that the reflected signal emitted by the backscatter transmitter to the receiver is:
Figure RE-GDA0002895465040000054
receiver uniform linear array reception of reflected signals, as derived for ambient radio source signal reception, channel parameter gmFor all M e [0, M-1]The same is true. The reflected signals received by different array elements have phase differences due to the difference of the arrival directions of the signals. The reflected signal received by the array element with the receiver number m is as follows:
Figure RE-GDA0002895465040000055
where h represents the channel parameters between the ambient radio source and the backscatter, g represents the channel parameters between the backscatter and the receiver, and the subscript represents the correspondingly numbered antenna of the receiver.
Figure RE-GDA0002895465040000056
Representing the phase shift, θ, of the reflected signal received by the array element numbered m relative to the reflected signal of the array element numbered 0bIs the angle of arrival of the reflected signal. Defining a direction vector as ag(θb)＝[1,ag,1(θb),...,ag,M-1(θb)]TThe backscatter signals received by all array elements are:
Figure RE-GDA0002895465040000057
the signals received by the receiver are:
y(t)＝yd(t)+yb(t)+ω(t)
where ω (t) is the noise subject to a circularly symmetric Gaussian distribution.
The receiver performs digital signal processing on the received signals to obtain reliable estimation of the arrival angle of each component of the received signals, obtains a plurality of angles of the reflected signals of the reverse scatterers by designing a specific receiving scheme, and further calculates to obtain two-dimensional coordinate data of the reverse scatterers.
As for the algorithms for estimating the DOA by the received signal, there is more, one of the following is exemplified:
the bandpass form of the signal received by the known receiver is as follows:
y(t)＝yd(t)+yb(t)+ω(t)
wherein the content of the first and second substances,
Figure RE-GDA0002895465040000061
ω (t) is the noise following a circularly symmetric Gaussian distribution with a variance σ2。af(θd)＝[1,af,1(θd),...,af,M-1(θd)]T， ag(θb)＝[1,ag,1(θb),...,ag,M-1(θb)]TIs a vector of the direction of the light,
Figure RE-GDA0002895465040000062
Figure RE-GDA0002895465040000063
the digital signal obtained after the receiver performs coherent reception, sampling and digital signal processing is
Figure RE-GDA0002895465040000064
s (n) represents the symbol corresponding to the ambient radio source signal, and c (n) represents the symbol generated by the backscatter itself. The carrier wave is removed from the received and processed digital signal, but the phase offset between the received signals of different array elements still exists.
Then, y (n) is processed to obtain DOA information of two signal components in y (n).
The specific DOA estimation algorithm is implemented as follows:
1. according to the set sampling number N, sampling for N times to obtain a sample sequence y (N), wherein
Figure RE-GDA0002895465040000066
2. Calculating y (n) autocorrelation matrix R, R ═ E { y (n) yH(n) where the statistical average may be replaced by a time average, i.e.
Figure RE-GDA0002895465040000065
3. Performing eigenvalue decomposition on R, and obtaining the minimum normalized eigenvector u corresponding to M-2 eigenvalues because the number of target signals is only 2iWhere i is 3,4 …, M.
ui＝[ui0,ui1,...ui(m-1)]T
4. Construct vector a (z), a (z) [1, z ]-1,...,z-(M-1)]T。
The following function is constructed:
Figure RE-GDA0002895465040000071
Figure RE-GDA0002895465040000072
multiplying by self conjugate transpose to obtain fi(z)＝aH(z)uiui Ha(z)＝|aH(z)ui|2,i＝3,4,...,M。
5. Defining polynomial
Figure RE-GDA0002895465040000073
Let it be 0, solve the equation. And obtaining the value of z.
6. The number of target signals is 2, the z value is subjected to modulo subtraction by 1, and then the absolute value is taken to be sorted from small to large. This will find the 4 roots closest to modulo 1 (heavy roots will appear). Since the signal reflected by the back scatterer undergoes two attenuations, its signal strength is much less than the direct signal. The first root, i.e. the root with the mode closest to 1, represents the angle of arrival of the direct signal and the 4 th root represents the angle of arrival of the signal reflected by the back scatterer.
7. Since z is ejφPhi is the spatial angular frequency, phi ═ pi sin theta. Thus, it is possible to provide
Figure RE-GDA0002895465040000074
And calculating to obtain the signal arrival direction estimation.
After the arrival angle of the backscatter signal is obtained, the coordinates of the backscatter device can be calculated, and the complete process is shown in fig. 2, since the environmental radio frequency source is a signal source already existing in the environment and no other setting is needed, taking the reception of one receiver as an example:
1. starting the backward scatterer, activating an internal circuit, and controlling the internal impedance switching state of the backward scatterer by the symbol c (n) of the backward scatterer to reflect the environment radio frequency signal.
2. Starting the receiver at a known coordinate point, which is set to (x)0,y0)。
3. And the receiver receives the signals and collects N sampling points to estimate the arrival direction of the primary reverse scatterer signals.
4. The receiver moves to another known coordinate point, which is set to (x)1,y1). The receiver antenna orientation is unchanged.
5. And the receiver receives the signals and collects N sampling points to estimate the arrival direction of the primary reverse scatterer signals.
6. And calculating the coordinates of the reverse scatterer according to the two measurement results.
According to the principle of triangulation, assuming that the antenna is oriented in the positive y-axis direction, the signal incident from the left side is at a positive angle, the signal incident from the right side is at a negative angle, and the estimated arrival angle of the signal is in the range of θ e [ -90 °,90 °]When Tag is in the position of
Figure RE-GDA0002895465040000081
When, set the receiver at (x)0,y0) The estimated angle is theta0In (x)1,y1) The estimated angle is theta1. Then there are:
Figure RE-GDA0002895465040000082
Figure RE-GDA0002895465040000083
the above is a system scheme proposed for one receiver, and two receivers can be used instead of the mobile operation of the receiver to obtain two measurements to calculate the backscatter coordinates.
As shown in fig. 3, for the performance simulation result, the angle estimation deviation value is set to be not more than 1 ° as an effective estimation, and the probability of effective estimation under different conditions is calculated through several monte carlo experiments. The signal-to-noise ratio of the back scatterer reflected signal to the noise is set to be in the range of-10 dB to-28 dB, and the ratio of the direct link signal-to-noise ratio to the reflected link signal-to-noise ratio is fixed to be 10 dB. Thus, the direct link signal-to-noise ratio ranges between 0dB to-18 dB. The environment signal is set to be a signal which is subjected to Gaussian distribution, the channel parameter is a channel parameter which is subjected to block fading and is subjected to Rayleigh distribution, the reflection symbol period is set to be 8 times of the environment signal symbol period, 10000 sample points are set to be collected in each calculation, and the number of array elements of the receiver is 8.
From simulation results, it can be known that a more accurate estimation (more than 95% accuracy) can be obtained when the signal-to-noise ratio is above-18 dB, and the estimation performance is seriously deteriorated when the signal-to-noise ratio is lower than the value.

Claims (6)

1. A positioning system based on environmental backscattering is characterized by comprising a radio frequency source, a plurality of receivers with M antennas and a backscattering device, wherein M is more than or equal to 3; the receiver receives the direct link signal and the environmental signal which is backscattered by the backscattering device, the receiver respectively obtains the arrival angles of the direct link signal and the backscattering signal, and the coordinates of the backscattering device are obtained according to the arrival angles of the backscattering signal and the known position coordinates of the plurality of receivers.
2. The environmental backscatter based positioning system of claim 1, wherein the specific method for the receiver to obtain the angles of arrival of the direct link signal and the backscatter signal respectively is:
assume that the signal received by the receiver is:
y(t)＝yd(t)+yb(t)+ω(t)
wherein, yd(t) is the received direct link signal, yb(t) isA received backscatter signal, ω (t) being noise subject to a circularly symmetric gaussian distribution; the arrival angles of the direct link signal and the backscatter signal are obtained through a DOA estimation algorithm, and the arrival angles of the direct link signal and the backscatter signal are distinguished according to the characteristic that the backscatter signal is subjected to fading twice compared with the direct link signal.
3. The environmental backscatter based positioning system of claim 2, wherein the specific method for obtaining the coordinates of the backscatter device is:
suppose the position coordinates are (x)0,y0) The receiver obtains an angle of arrival of theta0In the position coordinate of (x)1,y1) The receiver obtains an angle of arrival of theta1Obtaining the coordinates of the backscatter means
Figure FDA0002824421010000011
Comprises the following steps:
Figure FDA0002824421010000012
Figure FDA0002824421010000013
4. a positioning system based on environmental backscattering is characterized by comprising a radio frequency source, a receiver with M antennas and a backscattering device, wherein M is more than or equal to 3; the receiver receives the direct link signal and the environmental signal which is backscattered by the backscattering device, the receiver respectively obtains the arrival angles of the direct link signal and the backscattering signal, and the coordinates of the backscattering device are obtained according to the arrival angles of the backscattering signal obtained by the receiver at different position coordinates.
5. The environmental backscatter based positioning system of claim 4, wherein the specific method for the receiver to obtain the angles of arrival of the direct link signal and the backscatter signal respectively is:
assume that the signal received by the receiver is:
y(t)＝yd(t)+yb(t)+ω(t)
wherein, yd(t) is the received direct link signal, yb(t) is the received backscatter signal, ω (t) is the noise subject to a circularly symmetric gaussian distribution; the arrival angles of the direct link signal and the backscatter signal are obtained through a DOA estimation algorithm, and the arrival angles of the direct link signal and the backscatter signal are distinguished according to the characteristic that the backscatter signal is subjected to fading twice compared with the direct link signal.
6. The environmental backscatter based positioning system of claim 5, wherein the specific method for obtaining the coordinates of the backscatter device is:
assume that the receiver is at position coordinate (x)0,y0) To obtain an angle of arrival of theta0Moving the receiver to a position coordinate (x)1,y1) To obtain an angle of arrival of theta1Obtaining the coordinates of the backscatter means
Figure FDA0002824421010000021
Comprises the following steps:
Figure FDA0002824421010000022
Figure FDA0002824421010000023
CN202011425053.XA 2020-12-09 2020-12-09 Positioning system based on environment backscattering Active CN112505624B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011425053.XA CN112505624B (en) 2020-12-09 2020-12-09 Positioning system based on environment backscattering

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011425053.XA CN112505624B (en) 2020-12-09 2020-12-09 Positioning system based on environment backscattering

Publications (2)

Publication Number Publication Date
CN112505624A true CN112505624A (en) 2021-03-16
CN112505624B CN112505624B (en) 2023-01-24

Family

ID=74971559

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011425053.XA Active CN112505624B (en) 2020-12-09 2020-12-09 Positioning system based on environment backscattering

Country Status (1)

Country Link
CN (1) CN112505624B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022200673A1 (en) * 2021-03-22 2022-09-29 Nokia Technologies Oy Use of sidelink communications for backscatter node positioning within wireless networks

Citations (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE358739B (en) * 1969-05-19 1973-08-06 Inst Francais Du Petrole
US3960449A (en) * 1975-06-05 1976-06-01 The Board Of Trustees Of Leland Stanford Junior University Measurement of angular dependence of scattered light in a flowing stream
US5729640A (en) * 1992-11-30 1998-03-17 Breault Research Organization Process of acquiring with an X=Y scannable array camera light emanted from a subject
US20040207527A1 (en) * 2001-02-12 2004-10-21 Matrics, Inc. Identification tag utilizing charge pumps for voltage supply generation and data recovery
CN101047415A (en) * 2007-05-08 2007-10-03 电子科技大学 Distribution multi-antenna communication method and system based on focus signal
CN101986756A (en) * 2010-10-25 2011-03-16 电子科技大学 Time-reversal signal-based wireless positioning scheme
US20120293355A1 (en) * 2009-12-29 2012-11-22 Israel Aerospace Industries Ltd. System and method for detecting concealed explosives and weapons
KR101622536B1 (en) * 2015-04-21 2016-05-19 경희대학교 산학협력단 Wireless communication apparatus, method of localization using the same and wireless communication system including the same
CN106549692A (en) * 2016-12-12 2017-03-29 电子科技大学 A kind of signal acceptance method for backscatter communication system
CN106793087A (en) * 2017-03-16 2017-05-31 天津大学 A kind of array antenna indoor positioning algorithms based on AOA and PDOA
US20190116078A1 (en) * 2014-02-11 2019-04-18 University Of Washington Apparatuses, systems, and methods for communicating using mimo and spread spectrum coding in backscatter of ambient signals
CN109738851A (en) * 2019-01-22 2019-05-10 西安电子科技大学 A method of based on carrier phase measurement in super high frequency radio frequency identification positioning system
CN110224965A (en) * 2019-06-17 2019-09-10 电子科技大学 One kind being based on half blind receiver design method of OFDM backscatter communication system
CN110290491A (en) * 2019-05-17 2019-09-27 重庆邮电大学 A kind of indoor objects localization method based on multipath auxiliary
US10448211B1 (en) * 2018-11-07 2019-10-15 Adero, Inc. Organizing groups of physical objects using wireless tags
CN110441732A (en) * 2019-08-15 2019-11-12 电子科技大学 A kind of single station multi-target orientation method in strange scattering environments
CN110784248A (en) * 2019-11-01 2020-02-11 电子科技大学 Frequency control array environment backscattering communication self-adaptive detection method based on double thresholds
CN110933626A (en) * 2019-11-05 2020-03-27 东南大学 High-precision self-organizing network type indoor positioning method
KR102097229B1 (en) * 2019-01-31 2020-04-03 한국산업기술대학교산학협력단 System for ambient backscatter communication system using artificial noise-aided scheduling for improving physical layer security
CN111398894A (en) * 2020-04-03 2020-07-10 中国电子科技集团公司第二十八研究所 Low-slow small target detection tracking system and method based on mobile communication network

Patent Citations (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE358739B (en) * 1969-05-19 1973-08-06 Inst Francais Du Petrole
US3960449A (en) * 1975-06-05 1976-06-01 The Board Of Trustees Of Leland Stanford Junior University Measurement of angular dependence of scattered light in a flowing stream
US5729640A (en) * 1992-11-30 1998-03-17 Breault Research Organization Process of acquiring with an X=Y scannable array camera light emanted from a subject
US20040207527A1 (en) * 2001-02-12 2004-10-21 Matrics, Inc. Identification tag utilizing charge pumps for voltage supply generation and data recovery
CN101047415A (en) * 2007-05-08 2007-10-03 电子科技大学 Distribution multi-antenna communication method and system based on focus signal
US20120293355A1 (en) * 2009-12-29 2012-11-22 Israel Aerospace Industries Ltd. System and method for detecting concealed explosives and weapons
CN101986756A (en) * 2010-10-25 2011-03-16 电子科技大学 Time-reversal signal-based wireless positioning scheme
US20190116078A1 (en) * 2014-02-11 2019-04-18 University Of Washington Apparatuses, systems, and methods for communicating using mimo and spread spectrum coding in backscatter of ambient signals
KR101622536B1 (en) * 2015-04-21 2016-05-19 경희대학교 산학협력단 Wireless communication apparatus, method of localization using the same and wireless communication system including the same
CN106549692A (en) * 2016-12-12 2017-03-29 电子科技大学 A kind of signal acceptance method for backscatter communication system
CN106793087A (en) * 2017-03-16 2017-05-31 天津大学 A kind of array antenna indoor positioning algorithms based on AOA and PDOA
US10448211B1 (en) * 2018-11-07 2019-10-15 Adero, Inc. Organizing groups of physical objects using wireless tags
CN109738851A (en) * 2019-01-22 2019-05-10 西安电子科技大学 A method of based on carrier phase measurement in super high frequency radio frequency identification positioning system
KR102097229B1 (en) * 2019-01-31 2020-04-03 한국산업기술대학교산학협력단 System for ambient backscatter communication system using artificial noise-aided scheduling for improving physical layer security
CN110290491A (en) * 2019-05-17 2019-09-27 重庆邮电大学 A kind of indoor objects localization method based on multipath auxiliary
CN110224965A (en) * 2019-06-17 2019-09-10 电子科技大学 One kind being based on half blind receiver design method of OFDM backscatter communication system
CN110441732A (en) * 2019-08-15 2019-11-12 电子科技大学 A kind of single station multi-target orientation method in strange scattering environments
CN110784248A (en) * 2019-11-01 2020-02-11 电子科技大学 Frequency control array environment backscattering communication self-adaptive detection method based on double thresholds
CN110933626A (en) * 2019-11-05 2020-03-27 东南大学 High-precision self-organizing network type indoor positioning method
CN111398894A (en) * 2020-04-03 2020-07-10 中国电子科技集团公司第二十八研究所 Low-slow small target detection tracking system and method based on mobile communication network

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
KI HYEON JANG 等: "":IEEE,Showing 1-22 of 22 for ambient backscatter and location"", 《2019 ELEVENTH INTERNATIONAL CONFERENCE ON UBIQUITOUS AND FUTURE NETWORKS (ICUFN)》 *
WU YAN 等: ""Transmit Diversity Schemes for MIMO-OFDM Based Wireless Lan Systems"", 《2006 IEEE 17TH INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS》 *
侯缓缓: ""无线室内定位中的环境适应方法研究与实现"", 《中国优秀硕士论文全文数据库》 *
裴曙阳: ""基于AOA和PDOA的无源UHF RFID室内定位算法研究"", 《中国优秀硕士论文全文数据库》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022200673A1 (en) * 2021-03-22 2022-09-29 Nokia Technologies Oy Use of sidelink communications for backscatter node positioning within wireless networks

Also Published As

Publication number Publication date
CN112505624B (en) 2023-01-24

Similar Documents

Publication Publication Date Title
Oumar et al. Comparison between MUSIC and ESPRIT direction of arrival estimation algorithms for wireless communication systems
El-Sayed et al. Evaluation of localization methods in millimeter-wave wireless systems
WO2021003757A1 (en) Indoor positioning method and system based on signal multipath propagation measurement
CN106909779B (en) MIMO radar Cramér-Rao lower bound calculation method based on distributed treatment
Werner et al. Sectorized antenna-based DoA estimation and localization: Advanced algorithms and measurements
KR20160105441A (en) Localization with non-synchronous emission and multipath transmission
CN112954792B (en) Multi-reflection device joint positioning and communication method based on environment backscattering
HajiAkhondi-Meybodi et al. Bluetooth low energy and CNN-based angle of arrival localization in presence of Rayleigh fading
Vukmirović et al. Position estimation with a millimeter-wave massive MIMO system based on distributed steerable phased antenna arrays
CN112986905A (en) Multi-reflection equipment positioning method based on environmental backscattering
Wymeersch A Fisher information analysis of joint localization and synchronization in near field
CN112505624B (en) Positioning system based on environment backscattering
Tsai et al. Beam AoD-based indoor positioning for 60 GHz MmWave system
Jeong et al. Joint TOA/AOA-based localization in wireless sensor networks
CN105589063B (en) Impulse radio 60GHz distance-finding methods based on the degree of bias
Takahashi et al. Accuracy comparison of wireless indoor positioning using single anchor: Tof only versus tof-doa hybrid method
Lagunas et al. UWB joint TOA and DOA estimation
JP2004061468A (en) Method for estimating arrival direction of multiplex wave using spatial characteristic and receiving beam formation device using the same
Ferréol et al. A low-cost AOA-TDOA approach for blind geolocation in multi-paths context
Buvarp et al. Probability-reduction of geolocation using reconfigurable intelligent surface reflections
Kamal et al. Performance evaluation of correlative interferometry for angle of arrival estimation
Fens et al. Channel characterization using radar for transmission of communication signals
Zhang et al. A Novel Map Matching Based Localization Method for ISAC
Boiko et al. Possibilities of the MUSIC Algorithm for WI-FI Positioning According to the IEEE 802.11 az Standard
CN113766424B (en) Unmanned aerial vehicle indoor positioning method, unmanned aerial vehicle indoor positioning device, computer equipment and storage medium

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant