CN110392387B - Method and apparatus for angle measurement of wireless signals - Google Patents

Method and apparatus for angle measurement of wireless signals Download PDF

Info

Publication number
CN110392387B
CN110392387B CN201810365866.0A CN201810365866A CN110392387B CN 110392387 B CN110392387 B CN 110392387B CN 201810365866 A CN201810365866 A CN 201810365866A CN 110392387 B CN110392387 B CN 110392387B
Authority
CN
China
Prior art keywords
path
energy
paths
wireless
wireless signal
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.)
Active
Application number
CN201810365866.0A
Other languages
Chinese (zh)
Other versions
CN110392387A (en
Inventor
潘淳
桑燃
周晓
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.)
Huawei Technologies Co Ltd
Original Assignee
Huawei Technologies Co Ltd
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 Huawei Technologies Co Ltd filed Critical Huawei Technologies Co Ltd
Priority to CN201810365866.0A priority Critical patent/CN110392387B/en
Publication of CN110392387A publication Critical patent/CN110392387A/en
Application granted granted Critical
Publication of CN110392387B publication Critical patent/CN110392387B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/08—Testing, supervising or monitoring using real traffic
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0083—Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/24—Reselection being triggered by specific parameters
    • H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24—Cell structures
    • H04W16/28—Cell structures using beam steering

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Provided are a method and a device for measuring an angle of a wireless signal. Wherein, the method comprises the following steps: the wireless device receives signals by an antenna array, wherein the signals comprise wireless signals transmitted by the device to be identified and transmitted by a plurality of paths; acquiring an incident angle and energy of the wireless signal transmitted via each of the plurality of paths; the wireless device adjusting the energy of the wireless signal transmitted by each path based on an antenna pattern of the antenna array, wherein the antenna pattern is a function of an angular value to a gain of the antenna array; and determining whether the candidate path in the plurality of paths is a direct path or not based on the adjusted energy of the wireless signal transmitted by each path. By implementing the embodiment of the application, the problem of wrong judgment of the direct beam path can be solved by utilizing an antenna receiving gain compensation mode, and the accuracy of incident angle judgment is further improved.

Description

Method and apparatus for angle measurement of wireless signals
Technical Field
The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for measuring an angle of a wireless signal.
Background
A Wireless Local Area Network (WLAN) may provide location capabilities.
The WLAN positioning system can determine the angle of arrival (AOA) of the wireless signal. The wireless signal transmitted by the device to be identified may reach the WLAN device via multiple paths. The content of the wireless signals arriving at the WLAN device along different paths is the same and therefore a copy of the same wireless signal. The signal received by the WLAN device is a superposition of the wireless signals that successively arrive at the WLAN device via multiple paths. The AOA of wireless signals arriving at the WLAN device via different paths is different. Since the AOA of a wireless signal of a line of sight (LOS) path (i.e., a direct path) is a correct angle of a device to be identified, a WLAN device (e.g., an Access Point (AP)) measuring AOA needs to determine a LOS path between the device to be identified (e.g., a terminal) and the WLAN device and a corresponding incident angle thereof.
Disclosure of Invention
The application provides an angle measurement method of a wireless signal and wireless equipment, which can improve the accuracy of a direct beam path and the judgment of a corresponding incident angle.
In a first aspect, a method for measuring an angle of a wireless signal is provided, including: the wireless device receives signals, wherein the signals comprise wireless signals transmitted by the device to be identified and transmitted by a plurality of paths;
acquiring an incident angle and energy of the wireless signal transmitted via each of the plurality of paths;
the wireless equipment removes antenna receiving gain under a corresponding incident angle in an antenna directional diagram of the wireless signal transmitted by each path to obtain the adjusted energy of the wireless signal transmitted by each path, wherein the antenna directional diagram is a function from an angle value to the gain of the antenna array;
and determining whether the candidate path in the plurality of paths is a direct path or not based on the adjusted energy of the wireless signal transmitted by each path.
Since the receiving antenna has different receiving gains at different angles, the irregular receiving gain may cause a certain fluctuation in the energy of the received signal, for example, when the incident angles of the direct path and the reflection path are different, there may be a case that the receiving gain of the antenna in the direct path is smaller than the receiving gain of the antenna in the reflection path, so that the energy difference between the received wireless signal propagating along the reflection path and the received wireless signal propagating along the direct path is not obvious, and the direct path cannot be accurately identified. In the embodiment, the energy of the wireless signal transmitted by each path is adjusted by using the antenna pattern of the antenna array, so that the accuracy of the judgment of the direct path and the corresponding incident angle is improved.
In an alternative implementation, the wireless device determines that the candidate path of the multiple paths is a direct path when a condition is satisfied, where the condition includes: the ratio of the energy of the wireless signal transmitted via the candidate path to the total energy of the signal is greater than a threshold.
After the energy of the wireless signals transmitted by each path is adjusted, if a direct path exists, the wireless signals transmitted along the direct path are always the strongest wireless signals in the wireless signals transmitted along all paths. However, the path through which the strongest wireless signal among the wireless signals transmitted along all paths passes is not necessarily the direct path, because even if there is no direct path, one wireless signal transmitted along the indirect path is the strongest among all the indirect paths. If there is no direct path, the strength of the wireless signal of one path is not absolutely superior among the wireless signals transmitted along the non-direct paths. Therefore, the direct path judgment accuracy is improved by taking the proportion of the energy of the wireless signal propagating along the single path in the total energy as the basis.
In an alternative implementation, the condition further includes: the energy of the wireless signal transmitted via the candidate path has a ratio in the total energy of the signal that is continuously greater than a threshold.
The energy ratio of the path meeting the conditions is continuously tracked, and the accuracy of direct path judgment can be ensured even if the terminal to be identified is in the moving process.
In an alternative implementation manner, the candidate path is a path of the multiple paths through which the wireless signal arriving first is transmitted.
Since the direct path must be shorter than any of the non-direct paths, the wireless signal transmitted via the direct path must reach the wireless device earlier than the wireless signal transmitted via the non-direct path. Therefore, the wireless device only checks whether the candidate path among the paths arrived first satisfies the above condition, and it is not necessary to check whether the energy of the wireless signal arrived later satisfies the above condition, so as to shorten the direct path identification process.
In an optional implementation manner, after the wireless device receives a signal, the wireless device matches the signal with a first training sequence to obtain a time point of receiving a plurality of second training sequences, where the signal includes the second training sequence, the signal includes a superposition of the plurality of second training sequences transmitted via the plurality of paths, the first training sequence is information stored by the wireless device, and values of the first training sequence and the second training sequence are the same.
The second training sequence is a Long Training Field (LTF) of the type in the wireless signal transmitted by the terminal to be identified. Before the wireless device and the device to be identified communicate, the wireless device stores a first training sequence, the device to be identified stores a second training sequence, the first training sequence and the second training sequence have the same value, and the training sequence in the wireless signal is unique. The wireless device can determine the time point of receiving the wireless signal transmitted by each path by utilizing the good autocorrelation of the training sequence, and can determine the path of the wireless signal received earliest as a candidate direct path, thereby simplifying the subsequent processing process and reducing the computational complexity.
In an alternative implementation, the wireless device correlates the signal with the first training sequence to obtain a plurality of pulse signals, and the wireless device uses the occurrence time of the peak of the plurality of pulse signals as the time point for receiving the plurality of second training sequences.
The wireless device obtains the distribution of the time of arrival of the first LTF at the wireless device in the plurality of paths in the time domain by utilizing the good autocorrelation of the training sequence, so that the path of the earliest received wireless signal can be determined as the candidate direct path.
In a second aspect, a wireless device is provided having functionality to implement the behavior of the wireless device in practice of the above method. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.
In a third aspect, a wireless device is provided, which may include: an antenna array and a processor, wherein the processor is used for processing the received signals,
the antenna is used for receiving signals, and the signals comprise wireless signals transmitted by the equipment to be identified and transmitted by a plurality of paths.
The processor is used for acquiring an incident angle and energy of a wireless signal transmitted through each path in the multiple paths according to a signal received by the antenna array, removing antenna receiving gain of the wireless signal transmitted through each path under the corresponding incident angle in an antenna directional diagram to obtain the adjusted energy of the wireless signal transmitted through each path, wherein the antenna directional diagram is a function from an angle value to the gain of the antenna array, and determining whether a candidate path in the multiple paths is a direct path or not based on the adjusted energy of the wireless signal transmitted through each path.
The wireless device may also include a memory coupled to the processor for storing program instructions and data necessary for the wireless device.
In a fourth aspect, a computer-readable storage medium is provided, which stores a computer program comprising program instructions that, when executed by a processor, cause the processor to perform a method of angle measurement of a wireless signal as provided in any one of the alternative implementations of the first aspect of the present application.
Drawings
Fig. 1 is a schematic diagram illustrating the propagation of a multipath signal according to an embodiment of the present invention;
fig. 2 is a schematic diagram of signal reception according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a sample superposition of multipath signals according to an embodiment of the present invention;
fig. 4 is a schematic view of receiving gain of the antenna at different angles according to the embodiment of the present invention;
fig. 5 is a schematic diagram illustrating an embodiment of adjusting the received energy of a wireless signal;
fig. 6 is a flowchart illustrating an angle measuring method for wireless signals according to an embodiment of the present invention;
FIG. 7 is a graph of the distribution of multiple propagation paths in time and space according to an embodiment of the present invention;
FIG. 8 is a schematic diagram of an angle-energy distribution function according to an embodiment of the present invention;
fig. 9 is a schematic diagram of a communication scenario according to an embodiment of the present invention;
fig. 10 is a schematic diagram of a positioning method based on an angle of arrival according to an embodiment of the present invention;
fig. 11 is a schematic structural diagram of a wireless device according to an embodiment of the present invention.
Fig. 12 is a schematic structural diagram of another wireless device according to an embodiment of the present invention.
Detailed Description
First, the related art related to the embodiments of the present invention will be described with reference to fig. 1 to 4.
Based on the AOA positioning system, a plurality of APs are usually required to obtain the arrival angle of the terminal message, and then the positioning server performs terminal positioning by using the arrival angle information obtained by the APs. However, in a wireless environment, multipath effects are the biggest problem affecting angle estimation, and due to the existence of a reflector, a plurality of electromagnetic signal propagation paths exist between a transmitter and a receiver, and referring to fig. 1, the multipath signal propagation diagram provided by the embodiment of the invention is shown. As shown in fig. 1, the uplink packet sent by the terminal reaches the AP through direct transmission and reflection.
When the signal reaches the receiving end through direct and reflected paths, the received signal may be represented as a superposition of multiple signal copies provided by multiple propagation paths, which is shown in fig. 2 and is a signal receiving diagram provided in the embodiment of the present invention. As shown in fig. 2, after the signal l (t) passes through the wireless environment, the arrival time points of the signals at the respective paths are different when the signal l (t) reaches the receiving end, and since each copy has its own propagation delay, the mathematical expression of the received signal may be represented as r (t) - ΣihiL(t-ti) Wherein t isiDenotes the delay of the ith propagation path, hiRepresenting the complex gain of the ith propagation path for the signal.
Because the propagation delay between the multiple paths has randomness, the time of the signals of the two different paths reaching the receiving end is similar, meanwhile, a certain resolution exists in the sampling interval of the receiver, and the time difference of the different paths reaching the receiving end is far smaller than the sampling interval of the receiver, so that the sampling signals comprise direct signals and reflected signals. Fig. 3 is a schematic diagram of a sample superposition of a multipath signal according to an embodiment of the present invention. As shown in fig. 3, during sampling, the sampled signal includes signals of two paths, so that incident signals on different paths cannot be distinguished in a time dimension, and the incident signals arriving on different paths need to be distinguished in a space dimension by an AOA algorithm.
In the AOA positioning system, for an AP, only the angle of arrival of a wireless signal propagating along a direct path is meaningful, the angle of arrival of a reflected path is meaningless, and interference is only caused, so that a key problem of the AOA positioning system is to correctly calculate the angle of arrival of the direct signal. Since the attenuation of the wireless signal is large after the wireless signal is reflected in the transmission process, when the wireless signal reaches the AP, the energy of the direct path is larger than that of the reflection path, so that the direct path is selected according to the energy of the received signal, and the method is an effective method. However, the receiving antenna of the AP receives the wireless signals at different angles and has different receiving gains, as shown in fig. 4, the receiving gain diagram is a schematic diagram corresponding to the antenna receiving the wireless signals at different angles, and the receiving gains of the antenna are different at different receiving angles. Since the irregular receiving gain of the antenna causes a certain fluctuation in the amplitude of the arriving signal, and the incident angles of the wireless signal propagating along the direct path and the wireless signal propagating along the reflected path are different, the antenna receiving gain of the wireless signal propagating along the direct path may be smaller than the antenna receiving gain of the wireless signal propagating along the reflected path, and the direct path may not be correctly identified, as shown in fig. 5, before the adjustment, the incident angle of the direct path is 120 degrees. The measured energy of the radio signal propagating along the direct path is-78 decibel-milliwatts (dBm), and the antenna receive gain of the antenna array at 120 degrees is-10 decibel (dB). The incident angle of the reflection path is 180 degrees. The measured energy along the reflected propagated radio signal has a value of-80 dBm. The antenna gain of the antenna array at 180 degrees of antenna reception is-4 dB. The actual energy value of the radio signal propagating along the direct path is-68 dBm, and the actual energy value of the radio signal propagating along the reflected path is-76 dBm, which can be inferred from the antenna receive gain. It can be seen that, before the adjustment, the difference between the energy of the wireless signal propagated along the direct path and the energy of the wireless signal propagated along the reflection path is not large enough, and the AP cannot accurately identify the direct path, whereas after the adjustment, the difference between the energy of the wireless signal propagated along the direct path and the energy of the wireless signal propagated along the reflection path is large, and the AP can correctly identify the direct path.
Next, an angle measurement method for a wireless signal according to an embodiment of the present invention will be described with reference to fig. 6.
Fig. 6 is a flowchart illustrating a method for measuring an angle of a wireless signal according to an embodiment of the present invention. As shown in fig. 6, the method comprises at least the following steps:
s101: the wireless device receives signals with an antenna array, the signals including wireless signals transmitted by a device to be identified that is transmitted via a plurality of paths.
In particular, the wireless device may include a terminal and a network device. The terminal referred to in the present application may include various handheld devices, vehicle-mounted devices, wearable devices (wearable devices), computing devices, and the like, which have wireless functions. For example, the network device referred to in this application may be an access point AP of a WLAN. The wireless signal may be a WLAN signal.
The terminal to be identified sends a wireless signal, and the wireless signal may be transmitted to the antenna array of the AP through multiple paths, such as a direct path, a reflected path, or a scattered path. The wireless signal of each path is a copy of the wireless signal sent by the terminal to be identified. That is, the signals received by the antenna array of the AP include direct-path wireless signals and/or non-direct-path wireless signals. Wherein the plurality of paths refers to 2 or more paths.
In one possible implementation, the AP may distinguish multiple paths transmitting wireless signals by clustering.
Specifically, the AP may collect a plurality of sample data, and determine a direct path of the terminal to be identified by using a clustering method. As shown in fig. 7, the data of each sample is represented by one point in the graph. Each sample is a wireless signal from one path received by the AP. The horizontal axis of the graph represents the time t at which each sample is received, and the vertical axis represents the AOA of that sample. The terminal to be identified sends a plurality of wireless signals, and each wireless signal reaches the AP through a plurality of paths and is received by the AP. Due to the continuity of the movement of the terminal to be identified, the angle change of each path also has continuity. The AP clusters the points in the graph. After clustering, the AP obtains multiple paths for transmitting wireless signals. The cluster of points for each shape in the graph represents a path, such as P1, P2, P3, P4, and P5. Each path in the graph may be a direct path or a non-direct path. The non-direct path refers to a path other than the direct path, such as a reflected, scattered or refracted path. The AP may identify the direct path of the AP according to the degree of dispersion of the clustering midpoint of each path (corresponding to the size of each circle in the coordinate graph). However, when the terminal to be identified moves rapidly, even if a direct path exists between the terminal to be identified and the AP, the degree of dispersion of the clustering midpoint of the direct path is large, so that the direct path cannot be identified.
Therefore, the clustering method is to distinguish a plurality of paths for transmitting wireless signals and then determine a direct path according to the dispersion degree of the midpoint in the cluster. Because the clustering method cannot accurately identify the direct path, but can accurately distinguish a plurality of paths, the AP can distinguish a plurality of paths for transmitting wireless signals by using the clustering method.
When a clustering method is adopted to distinguish multiple paths for transmitting wireless signals, the AP can improve the clustering accuracy by configuring multiple antennas (such as 3-4 antennas), so that the estimated AOA is more accurate, the direct path can be better identified, and the possibility that the AP cannot distinguish two or more paths to identify the two or more paths into one path to cause the energy superposition of the wireless signals on the paths is reduced.
In one possible implementation, the AP matches a signal with a first training sequence to obtain a time point for receiving a plurality of second training sequences, where the signal includes the second training sequence, the signal includes a superposition of the plurality of second training sequences transmitted via the plurality of paths, the first training sequence is a sequence stored by the AP, and values of the first training sequence and the second training sequence are the same.
Specifically, the second training sequence is a Long Training Field (LTF) in the WLAN wireless signal, and "second" is not a sequence number, but rather names the training sequences in the signal to distinguish from the training sequences stored by the AP and used for matching the signal, and the training sequences in the wireless signals transmitted by all terminals to be identified are the second training sequences. The "first" is not a sequence number, but rather a designation of the training sequence stored by the AP to distinguish it from the training sequence in the signal.
Specifically, the AP down-converts the acquired wireless signal, and converts the signal into a digital signal after analog-to-digital conversion. And carrying out correlation operation on the digital signal of each antenna and a first training sequence stored in the AP to obtain a corresponding pulse signal. The second training sequence sent by the terminal to be identified and the first training sequence stored by the AP are the same training sequence and have the same data information. And the AP separates the superposed second training sequences according to the characteristics of the pulse signal and obtains the distribution of each second training sequence in a time domain.
Because the training sequence has good autocorrelation characteristics in the time domain, the wireless signals with close receiving time can be distinguished by using the training sequence to identify the time for receiving the wireless signals, namely, the wireless signals have high resolution in the time domain. And the AP acquires the distribution of the plurality of paths on the time domain according to the distribution of the time points of the plurality of second training sequences on the time domain, thereby distinguishing the plurality of paths for transmitting the wireless signals.
In a possible implementation, the AP extracts Channel State Information (CSI) of a received signal according to a preamble sequence of a radio frame of the received signal, performs spatial spectrum estimation on the received signal according to the obtained CSI, and obtains a spatial spectrum function by using an AOA algorithm, where the spatial spectrum function is a function of an amplitude and an incident angle of the received signal at different times.
It should be noted that the AOA algorithm is not unique, and the AOA algorithm may be a beam forming method, a maximum entropy method, a minimum variance distortionless response method, a multiple signal classification method, or a feature subspace method, and the like.
S102: obtaining an incident angle and energy of the wireless signal transmitted via each of the plurality of paths.
Specifically, the wireless device may obtain the incident angle and the energy of the wireless signal transmitted through each path by distinguishing the multiple paths through a clustering method, obtain the incident angle and the energy of the wireless signal transmitted through each path by distinguishing the multiple paths through a sequence matching method, or obtain the incident angle and the energy of the wireless signal transmitted through each path through a CSI and AOA algorithm.
Referring to fig. 8, which is a schematic view of an angle-energy distribution function, the amplitudes have peaks at angles, which indicate that a wireless signal arrives at the angles, and the angles are incident angles of the wireless signal, as shown in fig. 8, the amplitudes have peaks at angles of 0 degrees, 20 degrees and 40 degrees, and correspond to-20 dBm, -30dBm and-40 dBm, which illustrates that the amplitude of the wireless signal is-20 dBm when the incident angle of the wireless signal arrives at AP and is 0 degrees, the amplitude of the wireless signal is-30 dBm when the incident angle of the wireless signal is 20 degrees, and the amplitude of the wireless signal is-40 dBm when the incident angle of the wireless signal is 40 degrees.
S103: the wireless equipment removes antenna receiving gain under a corresponding incident angle in an antenna directional diagram from the energy of the wireless signal transmitted by each path to obtain the adjusted energy of the wireless signal transmitted by each path, wherein the antenna directional diagram is a function from an angle value to the gain of the antenna array.
Specifically, as can be seen from fig. 4, the receiving antenna array of the AP has different receiving gains at different angles, so after obtaining the incident angle and the energy of the wireless signal transmitted through each path, the antenna receiving gain at each incident angle is found, and for each incident angle, the energy of the wireless signal transmitted through the incident angle is adjusted by using the antenna receiving gain corresponding to the incident angle, so as to obtain the adjusted energy of the wireless signal transmitted through each path. The adjustment is specifically defined as dividing the energy of the wireless signal transmitted by each path by (the original value, for example, the original value of 0dBm is 1 milliwatt)/subtracting (in logarithmic form) the corresponding antenna reception gain. For example, as shown in FIG. 5, the incident angle of the straight path is 120 degrees, the energy of the radio signal propagating along the straight path is-78 dBm, and the reception gain of the antenna array at 120 degrees is-10 dB, so the actual energy value of the radio signal propagating along the straight path is-78 dBm- (-10dB) and-68 dBm, and similarly, the incident angle of the reflection path is 180 degrees, the energy of the radio signal propagating along the reflection path is-80 dBm, and the reception gain of the antenna array at 180 degrees is-4 dB, so the actual energy value of the radio signal propagating along the reflection path is-80 dBm- (-4dB) and-76 dBm.
The antenna directional diagram can be stored in the AP in advance, the antenna directional diagram can be obtained by measuring and calibrating the receiving antenna in the AP in a microwave darkroom, and the microwave darkroom is artificially manufactured, so that the special space with a purer electromagnetic environment is provided, and the external electromagnetic interference can be effectively eliminated.
In one possible implementation, if the antenna patterns are not pre-stored in the APs, but stored in other devices or servers, these devices or servers may store the antenna patterns of multiple APs, and when an AP needs to use the antenna pattern to adjust the wireless signal energy, the AP needs to obtain the corresponding antenna pattern from the other devices or servers.
Specifically, the AP first establishes a data connection with another device or server for transmission of antenna pattern information, and the AP may send an indication identifier to the other device or server, and the other device or server finds the antenna pattern information corresponding to the AP according to the indication identifier and sends the antenna pattern information to the AP.
It can be seen that, by adjusting the energy of the wireless signal received by the AP by using the antenna directional diagram, the influence of the antenna receiving gain on the subsequent judgment of the direct-radiation signal can be eliminated, which is beneficial to improving the accuracy of the judgment of the direct-radiation path.
S104: and determining whether the candidate path in the plurality of paths is a direct path or not based on the adjusted energy of the wireless signal transmitted by each path.
In one possible implementation, the AP determines that a candidate path of the multiple paths is a direct path when a condition is satisfied, where the condition includes: the ratio of the energy of the wireless signal transmitted via the candidate path to the total energy of the signal is greater than a threshold.
Specifically, the AP may select a path to be checked among the plurality of paths before performing S104. The path to be inspected is at least one path that may include a direct path. The AP can also select all paths as paths to be checked, check whether all the paths respectively meet the judgment condition or not, and determine one path to be checked meeting the judgment condition as a direct path so as to reduce the complexity of software or hardware for identifying the direct path.
In one possible implementation, the AP selects at least one path of the first arriving wireless signal as the path to be inspected. It can be understood that, if a direct path exists between the AP and the terminal to be identified, one or more paths through which the wireless signal arrives first must include the direct path, that is, the path to be inspected must include the direct path. And the AP checks whether each path in the paths to be checked meets the judgment condition or not, and determines the path to be checked meeting the judgment condition as a direct path so as to shorten the identification process of the direct path.
If the resolution of the AP in the time domain is high enough, the AP can determine that the only path that transmits the first (first) arriving wireless signal is the path to be examined. And the AP checks whether the path to be checked meets a judgment condition, and if the path to be checked meets the judgment condition, the AP determines that the path to be checked is a direct path. That is, the AP only checks whether the energy of the one wireless signal satisfies the above condition. Therefore, the path for transmitting the first arriving wireless signal is selected as the path to be inspected, the number of the paths to be inspected is effectively reduced, and the time for determining the direct path by the AP is shortened.
When a path to be inspected exists, and the energy ratio of the energy of the wireless signal transmitted through the path to be inspected in the total energy of the signal is larger than a threshold value, the AP determines that the path to be inspected is a direct path; when the proportion of the energy of the wireless signal transmitted through any one path to be inspected in the total energy of the signal is smaller than the threshold value, the AP determines that no direct path exists.
In one possible implementation, the decision condition further includes: the ratio of the energy of the wireless signal transmitted by each of the plurality of paths to the total energy of the signal is continuously greater than the threshold.
Specifically, as shown in fig. 9, when the position of the terminal to be identified does not change, there is no blocking object on both of the two dashed paths between the terminal to be identified and the AP1 and the AP2, and at this time, the two dashed paths are the paths to be inspected of the AP1 and the AP2, and respectively satisfy: the energy proportion of the energy of the wireless signal transmitted via the path to be inspected in the total energy of the signal is greater than a threshold value. During the position change process of the terminal to be identified (moving upwards along the direction of the dotted line in the figure), no shielding object exists between the terminal to be identified and the AP1, the dotted line path still satisfies that the energy ratio of the energy of the wireless signal transmitted through the dotted line path in the total energy of the signal is greater than the threshold value, therefore, a direct path exists between the terminal to be identified AP1, a shielding object exists between the terminal to be identified and the AP2, the wireless signal needs to reach the AP2 through a reflection path or a scattering path, the energy ratio of the energy of the wireless signal transmitted through the path to be detected between the terminal to be identified and the AP2 in the total energy of the signal is less than the threshold value, and therefore, no direct path exists in the path to be detected between the terminal to be identified and the AP 2.
Therefore, the AP may decide on the path to be checked by a decision method of whether the energy of the wireless signal transmitted through the path to be checked in the total energy of the signal is continuously larger than a threshold, wherein the continuously may refer to a continuous time or a continuous number of times. The accuracy of identifying the direct path is improved by continuously comparing the energy ratio of the path to be detected with the threshold value.
In one possible implementation, after determining the direct path and the incident angle of the direct path, the AP extracts angle features, such as time for receiving a wireless signal, an angle of arrival, and related information of a terminal to be identified, such as time for sending the wireless signal and identification information of the terminal to be identified, from the physical layer data. The information is uploaded to a server and is classified, and the server integrates the information according to the Media Access Control (MAC) address of the corresponding terminal and the information such as the matching of the receiving time of the wireless signal, and the like, such as the identification of the terminal to be positioned and the arrival angle calculated by the wireless signal received at the same time, so as to complete the positioning of the terminal to be identified. As shown in fig. 10, the direct paths from the device to be identified to the first AP and the second AP correspond to the angles of arrival θ1And theta2Then, the intersection position of the two direct paths is the position of the device to be identified.
In order to facilitate a better implementation of the above-described solution of the embodiments of the present invention, the following also provides relevant means for implementing the above-described solution in a coordinated manner.
As shown in fig. 11, which is a schematic structural diagram of a wireless device provided in an embodiment of the present invention, the wireless device 100 includes at least: a receiving unit 110 and a processing unit 120, wherein,
the receiving unit 110 is configured to receive a signal including a wireless signal transmitted by a device to be identified transmitted via a plurality of paths.
The processing unit 120 is configured to obtain an incident angle and energy of a wireless signal transmitted through each of the multiple paths according to a signal received by the antenna array, remove an antenna reception gain at a corresponding incident angle in an antenna pattern from the energy of the wireless signal transmitted through each path, and obtain an adjusted energy of the wireless signal transmitted through each path, where the antenna pattern is a function from an angle value to the gain of the antenna array, and determine whether a candidate path in the multiple paths is a direct path based on the adjusted energy of the wireless signal transmitted through each path.
In a possible embodiment, the processing unit 120 is further configured to match a signal with a first training sequence to obtain a time point of receiving a plurality of second training sequences, where the wireless signal includes the second training sequence, the signal includes a superposition of the plurality of second training sequences transmitted via the plurality of paths, the first training sequence is information stored by the wireless device, and the first training sequence and the second training sequence have the same value.
In a possible embodiment, the processing unit 120 is further configured to correlate the signal with the second training sequence to obtain a plurality of pulse signals, and use the occurrence time of the peak of the plurality of pulse signals as the time point for receiving the plurality of first training sequences.
In a possible embodiment, the processing unit 120 is further configured to determine that the candidate path of the plurality of paths is a direct path when a condition is satisfied, where the condition includes: the ratio of the energy of the wireless signal transmitted via the candidate path to the total energy of the signal is greater than a threshold.
In a possible embodiment, the processing unit 120 is further configured to determine a direct path of the wireless signal and an incident angle corresponding to the direct path when a condition is satisfied, where the condition includes: the ratio of the energy of the wireless signal transmitted by each of the plurality of paths to the total energy of the signal is continuously greater than the threshold.
Fig. 12 is a wireless device 200 according to an embodiment of the present invention. The wireless device 200 comprises at least: a processor 210 and an antenna array 220.
The processor 210 may be a Central Processing Unit (CPU), or a combination of a CPU and a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a Programmable Logic Device (PLD), or a combination thereof. The PLD may be a Complex Programmable Logic Device (CPLD), a field-programmable gate array (FPGA), a General Array Logic (GAL), or any combination thereof. The processor 210 is used to control the overall network device and signal processing. Processor 210 may include a modem 211.
The modem 211 is used for modulation and demodulation of WLAN signals. The modem 211 is connected to the antenna 220 to receive and transmit WLAN signals.
The wireless device may also include memory 230, which memory 230 may include volatile memory, such as Random Access Memory (RAM); the memory 230 may also include a non-volatile memory such as a Read Only Memory (ROM), a flash memory (flash memory), a hard disk, or a solid state disk. Memory 230 may also include a combination of the above types of memory. The memory 230 is used to store various applications, operating systems, and data. The memory 230 may transmit the stored data to the processor 210.
It is understood that the memory 230 may be integrated into the processor 210 or may stand alone.
An antenna array 220 is used for receiving signals, and the signals comprise wireless signals transmitted by the devices to be identified and transmitted by a plurality of paths.
The processor 210 is configured to obtain an incident angle and energy of a wireless signal transmitted through each of the multiple paths according to a signal received by the antenna array, remove an antenna reception gain at a corresponding incident angle in an antenna pattern from the energy of the wireless signal transmitted through each path, and obtain adjusted energy of the wireless signal transmitted through each path, where the antenna pattern is a function from an angle value to the gain of the antenna array, and determine whether a candidate path in the multiple paths is a direct path based on the adjusted energy of the wireless signal transmitted through each path.
The processor 210 is further configured to determine a path of an earliest received wireless signal as a candidate direct path, the earliest received wireless signal corresponding to a first time point of the time points.
The processor 210 is further configured to determine a candidate path of the plurality of paths as a direct path when a condition is satisfied, the condition including a ratio of energy of a wireless signal transmitted via the candidate path to a total energy of the signal being greater than a threshold.
As the embodiments and the advantageous effects of the wireless device in the foregoing embodiments can refer to the method embodiments and the advantageous effects shown in fig. 6, detailed descriptions thereof are omitted here.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied in hardware, a software module executed by a processor, or a combination of the two. The software instructions may be comprised of corresponding software modules that may be stored in random access memory, flash memory, read-only memory, erasable programmable read-only memory (EPROM) memory, electrically erasable programmable read-only memory (EEPROM), a hard disk, an optical disk, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. Of course, the processor and the storage medium may reside as discrete components in user equipment.
Those skilled in the art will recognize that in one or more of the examples described above, the functions described herein may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium.
The above-mentioned embodiments, objects, technical solutions and advantages of the present application are further described in detail, it should be understood that the above-mentioned embodiments are only examples of the present application, and are not intended to limit the scope of the present application, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the present application should be included in the scope of the present application.

Claims (10)

1. A method of angular measurement of a wireless signal, comprising:
the wireless device receives signals by an antenna array, wherein the signals comprise wireless signals transmitted by the device to be identified and transmitted by a plurality of paths;
acquiring an incident angle and energy of the wireless signal transmitted via each of the plurality of paths;
removing antenna receiving gain of the wireless signal transmitted by each path under a corresponding incident angle in an antenna directional diagram to obtain the adjusted energy of the wireless signal transmitted by each path, wherein the antenna directional diagram is a function from an angle value to the gain of the antenna array;
and determining whether the candidate path in the plurality of paths is a direct path or not based on the adjusted energy of the wireless signal transmitted by each path.
2. The method of claim 1, wherein said determining whether a candidate path of the plurality of paths is a direct path based on the adjusted energy of the wireless signal transmitted by each path comprises:
determining, by the wireless device, that a candidate path of the plurality of paths is a direct path when a condition is satisfied, the condition including: the ratio of the energy of the wireless signal transmitted via the candidate path to the total energy of the signal is greater than a threshold.
3. The method of claim 2, wherein the conditions further comprise:
the energy of the wireless signal transmitted via the candidate path has a ratio in the total energy of the signal that is continuously greater than a threshold.
4. The method according to any one of claims 1 to 3, wherein the candidate path is a path of the plurality of paths through which the radio signal arrived first is transmitted.
5. The method of claim 4, wherein after the wireless device receives the signal, the method further comprises:
the wireless device matches the signal with a first training sequence to obtain a time point for receiving a plurality of second training sequences, wherein the signal includes the second training sequence, the signal includes a superposition of the plurality of second training sequences transmitted via the plurality of paths, the first training sequence is information stored by the wireless device, and values of the first training sequence and the second training sequence are the same.
6. A wireless device, wherein the device comprises: an antenna array and a processor, wherein,
the antenna array is used for receiving signals, and the signals comprise wireless signals transmitted by the equipment to be identified and transmitted by a plurality of paths;
the processor is configured to obtain an incident angle and energy of the wireless signal transmitted through each of the multiple paths, remove an antenna reception gain at a corresponding incident angle in an antenna pattern from the energy of the wireless signal transmitted through each path, and obtain an adjusted energy of the wireless signal transmitted through each path, where the antenna pattern is a function from an angle value to a gain of the antenna array, and determine whether a candidate path in the multiple paths is a direct path based on the adjusted energy of the wireless signal transmitted through each path.
7. The apparatus of claim 6,
when a condition is satisfied, the processor is further configured to determine that a candidate path of the plurality of paths is a direct path, where the condition includes: the ratio of the energy of the wireless signal transmitted via the candidate path to the total energy of the signal is greater than a threshold.
8. The apparatus of claim 7, wherein the conditions further comprise:
the energy of the wireless signal transmitted via the candidate path has a ratio in the total energy of the signal that is continuously greater than a threshold.
9. The apparatus according to any one of claims 6 to 8, wherein the candidate path is a path of the plurality of paths through which the wireless signal arrives first.
10. The device of claim 9, wherein after the wireless device receives the signal,
the processor is further configured to match the signal with a first training sequence to obtain a time point for receiving a plurality of second training sequences, where the signal includes the second training sequence, the signal includes a superposition of the plurality of second training sequences transmitted via the plurality of paths, the first training sequence is information stored by the wireless device, and values of the first training sequence and the second training sequence are the same.
CN201810365866.0A 2018-04-23 2018-04-23 Method and apparatus for angle measurement of wireless signals Active CN110392387B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810365866.0A CN110392387B (en) 2018-04-23 2018-04-23 Method and apparatus for angle measurement of wireless signals

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810365866.0A CN110392387B (en) 2018-04-23 2018-04-23 Method and apparatus for angle measurement of wireless signals

Publications (2)

Publication Number Publication Date
CN110392387A CN110392387A (en) 2019-10-29
CN110392387B true CN110392387B (en) 2021-05-18

Family

ID=68284378

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810365866.0A Active CN110392387B (en) 2018-04-23 2018-04-23 Method and apparatus for angle measurement of wireless signals

Country Status (1)

Country Link
CN (1) CN110392387B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113891334B (en) * 2021-09-26 2023-03-14 电子科技大学 Directional base station debugging method of high-speed magnetic levitation train ground communication system
WO2023159351A1 (en) * 2022-02-22 2023-08-31 Oppo广东移动通信有限公司 Wireless communication method and device

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1430367A (en) * 2001-12-30 2003-07-16 华为技术有限公司 Identification method of visible and non-visible channel in CDMA mobile communication system
CN1470885A (en) * 2002-07-23 2004-01-28 华为技术有限公司 Angle evaluating method for restraining multi-path influence
CN1508561A (en) * 2002-12-16 2004-06-30 华为技术有限公司 Apparatus for obtaining environmental data and method for realizing same
CN101860385A (en) * 2010-06-23 2010-10-13 西安交通大学 Channel modeling method for multi-input multi-output wireless communication system
CN102647785A (en) * 2012-03-23 2012-08-22 广州市香港科大霍英东研究院 Method for distinguishing wireless transmission multipath in wireless signal strength ranging technology
CN102664669A (en) * 2012-04-26 2012-09-12 厦门大学 Method for improving channel capacity of indoor distributed multi-input and multi-output system
CN102857310A (en) * 2012-07-27 2013-01-02 中兴通讯股份有限公司 Test method and device for wireless indexes of active antenna system
CN104662736A (en) * 2012-09-18 2015-05-27 艾斯特里克有限公司 Antenna system for interference suppression
CN104730349A (en) * 2015-04-15 2015-06-24 成都天衡电科科技有限公司 Linear motion based antenna gain direction diagram measurement method
CN105814809A (en) * 2013-12-16 2016-07-27 华为技术有限公司 Method and device for adjusting wavebeam width in wireless communication system
CN107171744A (en) * 2017-06-30 2017-09-15 北京世纪德辰通信技术有限公司 A kind of high-power station prologue test system and method based on three-dimensional map

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10359496B2 (en) * 2015-08-10 2019-07-23 Viasat, Inc. Satellite antenna with sensor for line-of-sight detection

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1430367A (en) * 2001-12-30 2003-07-16 华为技术有限公司 Identification method of visible and non-visible channel in CDMA mobile communication system
CN1470885A (en) * 2002-07-23 2004-01-28 华为技术有限公司 Angle evaluating method for restraining multi-path influence
CN1508561A (en) * 2002-12-16 2004-06-30 华为技术有限公司 Apparatus for obtaining environmental data and method for realizing same
CN101860385A (en) * 2010-06-23 2010-10-13 西安交通大学 Channel modeling method for multi-input multi-output wireless communication system
CN102647785A (en) * 2012-03-23 2012-08-22 广州市香港科大霍英东研究院 Method for distinguishing wireless transmission multipath in wireless signal strength ranging technology
CN102664669A (en) * 2012-04-26 2012-09-12 厦门大学 Method for improving channel capacity of indoor distributed multi-input and multi-output system
CN102857310A (en) * 2012-07-27 2013-01-02 中兴通讯股份有限公司 Test method and device for wireless indexes of active antenna system
CN104662736A (en) * 2012-09-18 2015-05-27 艾斯特里克有限公司 Antenna system for interference suppression
CN105814809A (en) * 2013-12-16 2016-07-27 华为技术有限公司 Method and device for adjusting wavebeam width in wireless communication system
CN104730349A (en) * 2015-04-15 2015-06-24 成都天衡电科科技有限公司 Linear motion based antenna gain direction diagram measurement method
CN107171744A (en) * 2017-06-30 2017-09-15 北京世纪德辰通信技术有限公司 A kind of high-power station prologue test system and method based on three-dimensional map

Also Published As

Publication number Publication date
CN110392387A (en) 2019-10-29

Similar Documents

Publication Publication Date Title
US11051267B2 (en) Channel latency determining method, positioning method, and related device
Xu et al. Pyramid: Real-time lora collision decoding with peak tracking
US8565106B2 (en) Iterative localization techniques
EP3550890B1 (en) Method for recognizing line-of-sight path, and wireless device
CN109413630B (en) Bluetooth RSSI value determination method and system
CN110392387B (en) Method and apparatus for angle measurement of wireless signals
CN107171981B (en) Channel correction method and device
CN112153557B (en) Wireless positioning method, positioning device and network equipment
Rastorgueva-Foi et al. Dynamic beam selection for beam-RSRP based direction finding in mmW 5G networks
Li et al. An iterative 5G positioning and synchronization algorithm in NLOS environments with multi-bounce paths
US20210281311A1 (en) Timing measurement method and related device
CN108243475B (en) Positioning method based on wireless network and wireless equipment
KR102416604B1 (en) Mehtod and device for precise positioning for wireless communication system
US20210349171A1 (en) Using recursive phase vector subspace estimation to localize and track client devices
CN112055408B (en) Terminal positioning method and direction finding system
CN109660935B (en) Interference positioning method for base station side array antenna system
US20050064909A1 (en) Beam assigning apparatus and method in a smart antenna system
WO2020099646A1 (en) Communication device and method
US20230388153A1 (en) Method for providing at least one estimated parameter of a wireless communication channel and radio receiver device
US20220361207A1 (en) Positioning Method and Apparatus, WLAN Device, and Storage Medium
Li et al. Wi-vision: An accurate and robust los/nlos identification system using hopkins statistic
CN115515154B (en) Occlusion recognition method and device and related equipment
CN115428478B (en) Method and device for fingerprint identification by adopting function-based matching mode
JP7282284B2 (en) Wireless communication device, wireless communication method, and program
Kenney et al. Direction Finding Antenna using Rotating Radome

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