Patent Description:
Object searching belongs to a common application of positioning and navigation. Some technical means may be used to assist object searching. Generally, if a location of a searched object and a location of a searcher can be determined separately, navigation may be performed with reference to a map, to indicate a searching path. The locations may be determined by using a positioning technology.

The positioning technology has a wide application prospect in fields such as a shopping guide in a mall, a guide in an underground parking lot, warehouse logistics, and intelligent plants. Some current positioning technologies are based on wireless signal measurement, for example, a positioning technology based on wireless signal strength, a time of flight of a signal, and an angle of arrival of a signal. Some current positioning technologies are based on all types of sensor information, for example, a positioning technology based on an inertial navigation sensor (an accelerometer, a gyroscope, or a magnetometer), a geomagnetic sensor, an optical sensor, a camera, or a voice sensor. In actual positioning application, usually, multiple location information sources are used at the same time to mark a location by using multiple positioning technologies.

In an existing positioning technology based on a wireless technology, a large quantity of anchors need to be deployed. The anchors are reference location points or objects whose locations are known. A wireless module is installed on a searched terminal. When searching for an object or a person, a terminal carried by a searcher first scans nearby anchors by using a wireless signal, to obtain a location of the searcher. At the same time, the searched object scans nearby anchors by using a wireless module, to obtain a location of the searched object, and sends the obtained location to the searcher by using a wireless signal. The searcher computes a navigation path according to the location of the searcher and the received location of the searched object, to search for the object or the person.

In the prior art, in a positioning process, a large quantity of reference objects whose locations are known need to be deployed, for example, anchors. Deployment of a large quantity of reference objects whose locations are known is complex, and in addition, deployment and maintenance of the reference objects whose locations are known are at very high costs, greatly increasing positioning costs.

In <CIT> it is disclosed that a mobile station determines its position using measured parameters of a wireless signal to improve a satellite positioning system (SPS) enhanced dead reckoning based position estimate. The mobile station uses SPS enhanced dead reckoning to estimate a current position. The mobile station receives wireless signals and measures, e.g., received signal strength and/or round trip time, which is compared to a database to derive a wireless signal based position estimate. The SPS enhanced dead reckoning position estimate and the wireless signal based position estimate may then be fused using corresponding confidence levels. The database may be generated and stored in the mobile station. In another embodiment, the database is generated and stored on an online server that may be accessed by mobile stations.

In <CIT> it is disclosed that a location of a mobile device in a venue can be estimated by using a state space estimator to determine candidate locations of the mobile device at a first time point based on previous candidate positions conditioned upon an observation of one or more environmental variables. A second observation is received at a second time point, and the state space estimator performs a propagation step to determine the candidate locations at the second time point based on the candidate locations at the first time point and the second observation. The propagation step includes a plurality of sub-propagation steps in which a time length between the sub-propagation steps is a fraction of the time length between the first and second time points, and at each sub-propagation step each candidate location is propagated according to a stochastic process. The location of the mobile device at the second time point is determined based on the candidate locations at the second time point.

Embodiments of the present invention provide an object searching method and a server, to reduce costs of deploying and maintaining anchors whose locations are known. In the following, parts of the description and drawings referring to embodiments not covered by the claims, are not part of the invention, but are illustrative examples necessary for understanding the invention.

A first aspect provides an object searching method, including:.

With reference to a first possible implementation of the first aspect, the obtaining coordinates of the searching terminal includes:.

With reference to the first possible implementation of the first aspect, the algorithm of computing the coordinates of the searched terminal according to the coordinates in the reference location record is specifically.

With reference to the first possible implementation of the first aspect, the algorithm of computing the coordinates of the searched terminal according to the coordinates in the reference location record and strength of a wireless signal sent by the searched terminal that is detected when the searching terminal sends the object searching request is specifically:;.

A second aspect provides a server, including a receiving module, a first coordinate obtaining module, a second coordinate obtaining module, a navigation path obtaining module, and a sending module:.

With reference to a first possible implementation of the second aspect, the first coordinate obtaining module comprises a reference coordinate obtaining unit and a coordinate obtaining unit, where:.

Exemplary embodiments are applicable to space within a particular range, referred to as object searching space. In the object searching space, in addition to an object that a searcher is to search for and that is referred to as a target searched object, there is another object the same as or similar to the target searched object. A location relationship between other objects and a location relationship between another object and the target searched object are relatively stable within a particular time period. Optionally, the another object in the object searching space may be a target searched object of another searcher. To distinguish between the another object in the object searching space and the target searched object in terms of concepts, the another object is referred to as another searched object. The target searched object and the another searched object in the object searching space are collectively referred to as a searched object. For example, a parking lot is object searching space, and all cars parked in the parking lot are searched objects. A car A is a car for which an owner B needs to search. In this case, the car A is a target searched object, and another car is another searched object.

To implement object searching, locations of a searcher and a target searched object need to be determined, and navigation is performed according to the locations of the searcher and the target searched object. A main technology is how to perform positioning, that is, how to determine the locations of the searcher and the target searched object. In an existing positioning technology, for example, a positioning technology based on a wireless technology, a large quantity of anchors need to be deployed. The anchors are nodes or reference objects whose locations are known. Then, the locations of the searcher and the target searched object are determined indirectly according to the locations of the anchors. In the technical solution provided in the examples, a feature that a location relationship between searched objects (including the target searched object) is relatively stable is used, and a location relationship between searched objects is determined based on a wireless signal technology and an inertial navigation measurement technology. Then, a location relationship between the searcher and an ambient searched object is determined. Finally, a location relationship between the searcher and the target searched object can be determined indirectly, thereby implementing navigation. Therefore, the location relationship between the searcher and the target searched object can be determined, that is, the locations of the searcher and the target searched object can be determined, when no anchor whose location is known is deployed.

As shown in <FIG>, the system includes the following key devices.

Searched terminal: a device that is arranged on a searched object (an object, a person, an animal, or the like) and at least can send an identifiable wireless signal. The searched terminal includes a target searched terminal and another searched terminal. Optionally, a device or signal source that has a function of sending an identifiable wireless signal and is static relative to a searched object in object searching space may be used as a searched terminal, for example, a WiFi device or a Bluetooth device. The identifiable wireless signal means that a wireless signal sent by a searched terminal carries a specific identifier, and the specific identifier is referred to as an identifier of the searched terminal.

Collection terminal: a device that has a function of receiving and transmitting wireless signals and is equipped with an inertial navigation sensor group (an accelerometer, a gyroscope, a compass, a barometer, and the like). The collection terminal is configured to obtain a location record sequence indicating a location relationship between searched terminals. A method for obtaining the location record sequence indicating the location relationship is described in detail in the following embodiments. Optionally, the inertial navigation sensor group may be classified into a distance measurement module and an angle of orientation measurement module according to functions. Optionally, a function of the inertial navigation sensor group may be implemented by using a hardware combination, or may be implemented by using a software module. Optionally, the collection terminal may be a device that is specially configured to obtain a location record sequence indicating a location relationship between searched terminals, or may be a collection terminal, such as a smartphone or a smartwatch, capable of implementing a function of obtaining a location record sequence indicating a location relationship between searched terminals.

Searching terminal: a device carried by a searcher and having a function of receiving and transmitting wireless signals. The searching terminal is configured to exchange data with a server. Optionally, the searching terminal is equipped with an inertial navigation sensor group (an accelerometer, a gyroscope, a compass, a barometer, and the like), may be used as a collection terminal in an object searching process, and is configured to obtain a location record sequence indicating a location relationship between searched terminals. Optionally, if the searching terminal has a relatively great processing capability, the searching terminal may be configured to compute a navigation path based on data sent by the server.

Server: a device that may be configured to receive and process location record sequences from the collection terminal, a request sent by the searching terminal, and data sent by the searched terminal, and combine the location record sequences from the collection terminal into a location record set indicating a location relationship between searched terminals in the object searching space. A method for combining, into the location record set, the location record sequences from the collection terminal and indicating location relationships is described in detail in the following embodiments. Optionally, the server may compute, based on the location record set, a navigation path from the searching terminal to the target searched terminal.

In the object searching system provided, the searching terminal may interact with the server by using a wireless communications technology, optionally, by using WiFi or Bluetooth. Optionally, the searched terminal interacts with the server by using a wireless technology. An objective of interaction between the searched terminal and the server lies in that if a location record of the searched terminal does not exist in a location record set, the searched terminal needs to send the obtained location record of the searched terminal to the server, or an auxiliary server obtains the location record of the searched terminal and adds the location record to the location record set.

An exemplary embodiment provides a location relationship obtaining method. As shown in <FIG>, specific steps are as follows:.

Further, the steps further include: S400. set coordinates of the benchmark location point as initial coordinates, and assign values to the initial coordinates; compute coordinates of the other reference location points based on the reference location relationship and the initial coordinates; and generate one location record for one of the reference location points, where the location record includes coordinates of the reference location point and an identifier of a searched terminal corresponding to the reference location point.

Further, the steps further include: S500. form a location record sequence by using all obtained location records. Optionally, the collection terminal sends the location record sequence to a server.

Optionally, the detecting wireless signals sent by ambient searched terminals in S100 includes: determining, based on a signal ratio, whether a wireless signal received by the collection terminal is a wireless signal sent by a searched terminal. Further, the determining, based on a signal ratio, whether a wireless signal received by the collection terminal is a wireless signal sent by a searched terminal includes: presetting a signal ratio threshold; determining whether a signal ratio of the wireless signal received by the collection terminal is greater than or equal to the signal ratio threshold; and if the signal ratio of the wireless signal received by the collection terminal is greater than or equal to the signal ratio threshold, determining that the wireless signal received by the collection terminal is the wireless signal sent by the searched terminal; or if the signal ratio is less than the signal ratio threshold, determining that the wireless signal received by the collection terminal is not the wireless signal sent by the searched terminal. For example, a preset ratio value is <NUM>%. The collection terminal moves along a straight-line track continuously for <NUM> seconds, and the collection terminal detects signals once every second. If a detected quantity of times that a signal source sends signals is less than <NUM>, the collection terminal does not process the signal source. If a detected quantity of times that a signal source sends signals is greater than or equal to <NUM>, the collection terminal processes the signal source.

An embodiment of the present invention provides a location relationship combining method, that is, a method for combining multiple received location sequences into a location record set. As shown in <FIG>, specific steps are as follows:.

Further, the steps further include: S3000. update the location record set.

Further, the method for combining the at least two location record sequences into a location record set in S2000 is shown in <FIG>. Specific steps are as follows:.

Further, the method for combining the next location record sequence with the location record set in S2300 is shown in <FIG>. Specific steps are as follows:.

Further, the method for updating the location record set in S3000 is shown in <FIG>. Specific steps are as follows:.

Further, the method for combining the location record sequence with the location record set in S3100 is shown in <FIG>. Specific steps are as follows:.

An embodiment of the present invention provides an object searching method. As shown in <FIG>, specific steps of the object searching method are as follows:.

When a computing capability of a searching terminal is limited, optionally, a server computes a navigation path and then sends the navigation path to the searching terminal for object searching. An embodiment of the present invention provides an object searching method. As shown in <FIG>, the specific object searching method includes the following steps:.

In this embodiment of the present invention, based on an object searching system including a searching terminal carried by a searcher, a searched terminal arranged on a searched object, and a server, by using a feature that a location relationship between searched objects is relatively stable, a location relationship is converted into a location record set whose basic elements are coordinates and an identifier, coordinates of a target searched object and coordinates of a searcher can be obtained in the location record set, and a navigation path is computed according to the coordinates of the target searched object and the coordinates of the searcher. Therefore, when no anchor whose location is known is deployed, a location relationship between the searched object and the searcher can be determined, and the target can be found quickly and simply according to a relative location relationship. In the object searching method provided in this embodiment of the present invention, no anchor whose location is known needs to be deployed, so that costs of deploying and maintaining anchors are reduced.

Based on descriptions of the foregoing embodiment, an embodiment of the present invention provides a method for computing coordinates of a searching terminal. A reference location record is a location record that is in a location record set and includes an identifier of an ambient searched terminal detected by the searching terminal. For the location record set, refer to the obtaining method described in the foregoing embodiments.

The method is implemented by using two algorithms: a centroid method and a weighted centroid method. Specific details are as follows:.

An embodiment of the present invention provides a location relationship obtaining method. As shown in <FIG>, a collection terminal detects, in a process of moving along a straight-line track, wireless signals sent by ambient searched terminals, and forms a signal sequence by using multiple wireless signals that have different strength and that are of a same detected searched terminal. In the moving process, the collection terminal measures, by using an inertial navigation sensor group, a distance and an angle of orientation relative to a location point that the collection terminal previously passes through, and may obtain, based on the distance and the angle of orientation that are measured by using the inertial navigation sensor group, a location relationship between reference location points that the collection terminal passes through. The reference location point is a location point for detecting, by the collection terminal, a wireless signal that has greatest strength in the signal sequence.

Further, the obtained location relationship between the reference location points is converted into coordinates for representation. A specific method is: setting coordinates of any one of the reference location points as initial coordinates and assigning values to the initial coordinates; and computing coordinates of the other reference location points in a same coordinate system based on the distance and the angle of orientation that are measured by using the inertial navigation sensor group.

Further, an identifier of a wireless signal sent by a searched terminal and coordinates of a reference location point corresponding to the searched terminal are used to form a location record of the searched terminal.

Further, location records of multiple searched terminals detected by the collection terminal on the straight-line track are used to form a location record sequence along the straight-line track.

Generally, greater strength of a detected signal indicates a shorter distance between the collection terminal and the searched terminal. When the signal strength is the greatest, according to a geometrical principle, the searched terminal is most possibly on a line that is perpendicular to the straight-line track and passes through a corresponding location point. In this case, a distance between the collection terminal and the searched terminal is the shortest. Based on the foregoing theory, in the technical solution provided in this embodiment of the present invention, a location point for obtaining a signal having greatest strength is made in one-to-one correspondence with a searched terminal sending the signal. In this embodiment of the present invention, greatest strength in a signal sequence is a relative value. In the signal sequence, a changing trend of the signal strength may be: continuously increasing, or continuously decreasing, or increasing first and then decreasing. A signal having greatest relative strength certainly exists in a signal sequence. The signal is a wireless signal having greatest strength in the signal sequence.

In this embodiment of the present invention, the location point for obtaining the signal having the greatest strength is made in one-to-one correspondence with the searched terminal sending the signal, so that precision of determining a location relationship between searched terminals can be improved.

The present invention provides a method for combining multiple location sequences. The location sequences may be obtained by using the method provided in the foregoing embodiment, or may be obtained by using another method. As shown in <FIG>, specific steps are as follows:.

If a location record of at least one searched terminal in the location record sequence N exists in the location record set M, the location record sequence N and the location record set M are combined into a new location record set M. If no location record of a searched terminal in the location record sequence N exists in the location record set M, the location record sequence N is ignored and saved. That the location record of the searched terminal exists in the location record set M means that the location record of the searched terminal exists in both the location record sequence N and the location record set M. However, coordinates recorded in the two location records may not be the same, and are determined according to corresponding identifiers of the searched terminal in the location records.

Step <NUM> is repeated until all location record sequences are checked.

Step <NUM>. Determine whether a quantity of searched terminals in the location record set M increases.

If the quantity of searched terminals increases, all location record sequences ignored in step <NUM> are checked one by one, to determine whether a location record of at least one searched terminal exists in the location record set M. That the location record of the searched terminal exists in the location record set M means that the location record of the searched terminal exists in both the location record sequence N and the location record set M. However, coordinates recorded in the two location records may not be the same, and are determined according to corresponding identifiers of the searched terminal in the location records. If the location record of the at least one searched terminal exists in the location record set M, the location record sequence N and the location record set M are combined into a new location record set M. If no location record of a searched terminal exists in the location record set M, the location record sequence is ignored and saved, and a next location record ignored in step <NUM> is further checked until all location record sequences ignored in step <NUM> are checked.

If the quantity does not increase, step <NUM> is performed.

Step <NUM>. Restart the combining step when a new location record sequence is received.

Further, a specific algorithm of combining the location record sequence N and the location record set M into a new location record set M is as follows:.

Assuming that there are K same searched terminals in M and N,.

The computed coordinates of all searched terminals in the new M are updated to M.

Optionally, a weighted value a=W/(W+<NUM>), and W is a quantity of added location record sequences in the combining process. Optionally, the weighted value a may be <NUM>. An embodiment of the present invention provides a method for determining that a collection terminal moves along a straight-line track. As shown in <FIG>, the method specifically includes the following.

In a moving process, the collection terminal detects a direction change in real time by using a configured direction measurement module. Optionally, the collection terminal measures the direction change by using an accelerator or a compass. Optionally, the collection terminal performs detection once every second.

Further, the collection terminal presets a direction change ratio threshold. If a direction change detected by the direction measurement module exceeds the preset direction change threshold, it is determined that the collection terminal turns a corner. For example, if the direction measurement module of the collection terminal detects that a direction change, relative to an initial location, of a current location of the collection terminal exceeds <NUM> degrees, it is determined that the collection terminal turns a corner. The current location is the turning corner, and represents that a previous straight-line track ends and a new straight-line track starts. Optionally, a direction of a straight-line track is determined according to an average value of multiple detection values before the collection terminal turns a corner.

Optionally, in the moving process, although it is determined that the collection terminal does not turn a corner, if an accumulated moving distance of the collection terminal moving from the initial location or from a point at which a previous straight-line track ends reaches or exceeds a preset moving distance threshold, it is determined that the current straight-line movement track ends, and a new straight-line track starts.

In this embodiment of the present invention, it is determined, according to the direction change and the moving distance in the moving process, whether the collection terminal moves along a straight-line track, so that it can be ensured that the collection terminal moves along the straight-line track, thereby improving accuracy of obtaining, by the collection terminal, a location relationship between searched terminals.

A case shown in <FIG> may exist in object searching space. A searched terminal B is relatively far away from the other searched terminals. Because a length of a straight-line track is limited, there is a case in which a location record of the searched terminal B cannot be obtained during each detection. An appropriate quantity of auxiliary navigation terminals may be deployed. The auxiliary navigation terminal is in a relatively stable location relationship with the searched terminal, can send an identifiable wireless signal, and is considered as a searched terminal. Optionally, an environment signal source that is static relative to a location of the searched terminal may be used as an auxiliary navigation terminal, and is considered as a searched terminal. The auxiliary navigation terminal is deployed, to ensure that a location relationship between all searched terminals in the object searching space can be obtained.

When a location record including an identifier of a target searched terminal is not found in a location record set, an embodiment of the present invention provides a method for obtaining coordinates of a target searched terminal. As shown in <FIG>, the method is specifically as follows:.

In this embodiment of the present invention, the coordinates of the target searched terminal are computed according to coordinates of the another searched terminal detected by the target searched terminal, so that the location record of the target searched terminal can be obtained when the location record of the target searched terminal does not exist in the location record set.

An embodiment of the present invention provides a method for obtaining a location record sequence. As shown in <FIG>, the specific method is as follows:
A searched terminal <NUM> and a searched terminal <NUM> exist in object searching space, and actual locations of the searched terminals <NUM> and <NUM> are unknown. A collection terminal <NUM> moves along a straight-line track L. In a moving process, the collection terminal <NUM> receives wireless signals sent by the searched terminal <NUM> and the searched terminal <NUM>, detects the received wireless signals sent by the searched terminal <NUM> and the searched terminal <NUM>, forms a signal sequence <NUM> according to a detection result by using multiple detected wireless signals sent by the searched terminal <NUM>, and forms a signal sequence <NUM> according to the detection result by using multiple detected wireless signals sent by the searched terminal <NUM>. Strength of a wireless signal sent by the searched terminal <NUM> and detected by the collection terminal <NUM> at a location point A on the straight-line track L is the greatest. It can be learned from the figure that, the searched terminal <NUM> is on a straight line that passes through the location point A and is perpendicular to the straight-line track L. A distance between the collection terminal <NUM> and the searched terminal <NUM> is the shortest at the location point A, and the location point A may be used to represent the searched terminal <NUM>. Likewise, a location point B may be used to represent the searched terminal <NUM>. A location relationship between the location point A and the location point B represents a location relationship between the searched terminal <NUM> and the searched terminal <NUM>. The location relationship between the location point A and the location point B is determined by using a distance and an angle of orientation that are measured by using an inertial navigation sensor group of the collection terminal <NUM>.

Further, the location relationship between the location point A and the location point B is converted into coordinates for representation. As shown in <FIG>, that the collection terminal moves along a straight-line track on a plane is used as an example, and the specific method is as follows:
An X-Y coordinate system is established with an X axis and a Y axis perpendicular to each other. A track from the location point A to the location point B is separately projected onto the X axis and the Y axis. The location point A and the location point B may be respectively represented by using X and Y. Coordinates of the location point A are (x1, y1), and coordinates of the location point B are (x2, y2). Specifically, a direction change measured by the inertial navigation sensor group of the collection terminal moving from the location point A to the location point B is α in a unit of a degree. A distance measured by the inertial navigation sensor group of the collection terminal moving from the location point A to the location point B is d. Therefore, it may be obtained that x2-x1=d×cosα, and y2-y1=d×sinα. Optionally, assuming that the coordinates of the location point A are (<NUM>, <NUM>), the coordinates of the location point B are (d×cosα, d×sinα). The method for determining a location relationship between location points according to displacement measured by the inertial navigation sensor group may be applied to a scenario of determining a location relationship between at least two location points according to displacement. The coordinates of the location point A and an identifier of the searched terminal <NUM> are used to form a location record <NUM>=[signA(<NUM>, <NUM>)] of the searched terminal <NUM>. Likewise, the coordinates of the location point B and an identifier of the searched terminal <NUM> are used to form a location record <NUM>=[signB(d×cosα, d×sinα)] of the searched terminal <NUM>. The location record <NUM> and the location record <NUM> form a location record sequence={[signA(<NUM>, <NUM>)], [signB(d×cosα, d×sinα)]} of the collection terminal <NUM> on the straight-line track L.

In this embodiment of the present invention, coordinates of a location point for obtaining a signal having greatest strength and an identifier of a corresponding searched terminal are used to form a location record, so that a location relationship between multiple searched terminals whose locations are unknown can be determined, and a navigation path can be computed according to the location relationship between the searched terminals, thereby reducing costs of deploying and maintaining anchors whose locations are known.

An embodiment of the present invention provides a method for obtaining a location record set. As shown in <FIG>, a server receives three location record sequences. A location record sequence <NUM> includes location records of searched terminals A, B, and C. Assuming that coordinates of A are (<NUM>, <NUM>), coordinates of B and coordinates of C are separately computed according to the coordinates of A and a location relationship between C and B, and are (xb, yb) and (xc, yc), and the location record sequence <NUM> is {[signA(<NUM>, <NUM>)], [signB(xb, yb)], [signC(xc, yc)]}. A location record sequence <NUM> includes location records of searched terminals B, C, D, and E. Assuming that coordinates of B are (<NUM>, <NUM>), coordinates of C, coordinates of D, and coordinates of E are separately computed according to the coordinates of B and a location relationship between C, D, and E, and are (uc, yc), (ud, yd), and (ue, ye), and the location record sequence <NUM> is {[signB(<NUM>, <NUM>)], [signC(uc, vc)], [signD(ud, vd)], [signE(ue, ve)]}. A location record sequence <NUM> includes location records of searched terminals E and F. Assuming that coordinates of E are (<NUM>, <NUM>), coordinates of F are computed according to the coordinates of E and a location relationship between E and F, and are (uf, vf), and the location record sequence <NUM> is {[signE(<NUM>, <NUM>)], [signF(uf, vf)]}.

The server configures a location record set M, and initializes M as an empty set; adds the first obtained location record sequence <NUM> to the location record set M, where M={A, B, C}; and checks the next location record sequence <NUM> {B, C, D, E}, where the location records of the searched terminals B and C that exist in the location record sequence <NUM> exist in the location record set M, so that the location record sequence <NUM> is combined with the location record set, the location records of the searched terminals D and E are newly added to M, and M={A, B, C, D, E}. A specific algorithm is: computing new coordinates (xb/<NUM>, yb/<NUM>) of B and new coordinates ((xc+uc)/<NUM>, (yc+vc)/<NUM>) of C according to Xi=a×xi+(<NUM>-a)×ui, Yi=a×yi+(<NUM>-a×vi), and Zi=a×zi+(<NUM>-a×wi), where a=<NUM>/<NUM>; separately computing new coordinates ((uc-xb-xc)/<NUM>, (vc-yb-yc)/<NUM>) of A, new coordinates ((uc-xb-xc)/<NUM>+ud, (vc-yb-yc)/<NUM>+vd) of D, and new coordinates ((uc-xb-xc)/<NUM>+ue, (vc-yb-yc)/<NUM>+ve) of E according to <MAT> and <MAT> ; updating the computed new coordinates of A, B, C, D, and E to the new M, to obtain M={[signA((uc-xb-xc)/<NUM>, (vc-yb-yc)/<NUM>)], [signB(xb/<NUM>, yb/<NUM>)], [signC((xc+uc)/<NUM>, (yc+vc)/<NUM>)], [signD((uc-xb-xc)/<NUM>+ud, (vc-yb-yc)/<NUM>+vd)], [signE((uc-xb-xc)/<NUM>+ue, (vc-yb-yc)/<NUM>+ve)]}.

The next location record sequence <NUM>={E, F} is checked, and the location record of the searched terminal E that exists in the location record sequence <NUM> exists in the location record set M. Then, the location record sequence <NUM> and the location record set M are combined, the location record of the searched terminal F is newly added to M, and M={A, B, C, D, E, F}. A specific algorithm is: computing new coordinates ((uc-xb-xc)/<NUM>+<NUM>×ue/<NUM>, (vc-yb-yc)/<NUM>+<NUM>×ve/<NUM>) of E according to Xi=a×xi+(<NUM>-a)×ui, Yi=a×yi+(<NUM>-a×vi), and Zi=a×zi+(<NUM>-a×wi), where a=<NUM>/<NUM>; separately computing new coordinates ((uc-xb-xc)/<NUM>-ue/<NUM>, (vc-yb-yc)/<NUM>-ve/<NUM>) of A, new coordinates ((<NUM>×xb+xc-uc)/<NUM>-ue/<NUM>, (<NUM>×yb+yc-vc)/<NUM>-ve/<NUM>) of B, new coordinates ((xb+<NUM>×xc+<NUM>×uc)/<NUM>-ue/<NUM>, (yb+<NUM>×yc+<NUM>×vc)/<NUM>-ve/<NUM>) of C, new coordinates ((uc-xb-xc)/<NUM>-ue/<NUM>+ud, (vc-yb-yc)/<NUM>-ve/<NUM>+vd) of D, and new coordinates ((xb+xc-uc)/<NUM>-ue/<NUM>+uf, (yb+yc-vc)/<NUM>-ve/<NUM>+vf) of F according to <MAT> and <MAT> ; updating the computed new coordinates of A, B, C, D, E, and F to the new M, to obtain M={[signA((uc-xb-xc)/<NUM>-ue/<NUM>, (vc-yb-yc)/<NUM>-ve/<NUM>)], [signB((<NUM>×xb+xc-uc)/<NUM>-ue/<NUM>, (<NUM>×yb+yc-vc)/<NUM>-ve/<NUM>)], [signC((xb+<NUM>×xc+<NUM>×uc)/<NUM>-ue/<NUM>, (yb+<NUM>×yc+<NUM>×vc)/<NUM>-ve/<NUM>)], [signD((uc-xb-xc)/<NUM>-ue/<NUM>+ud, (vc-yb-yc)/<NUM>-ve/<NUM>+vd)], [signE((uc-xb-xc)/<NUM>+<NUM>×ue/<NUM>, (vc-yb-yc)/<NUM>+<NUM>×e/<NUM>)], [signF((xb+xc-uc)/<NUM>-ue/<NUM>+uf, (yb+yc-vc)/<NUM>-ve/<NUM>+vf)]}.

In this embodiment of the present invention, by using coordinates of a same searched terminal in two location record sequences, coordinates of other searched terminals in a combined location record set are computed, and in this way, a location record set including location records of more searched terminals can be obtained.

In the foregoing embodiments of the present invention, a searched object does not move within a time period, and a searcher searches for the target searched object by using a navigation path. However, there may be a scenario in which a searcher moves less or even does not move, but a searched object continuously moves. In this scenario, a location relationship between searched objects is still relatively stable, and the object searching method in the present invention is also applicable to the scenario. A difference lies in that a relative measurement module measures displacement data between the searcher and the searched object. A typical application scenario example is picking up luggage. As shown in <FIG>, a specific method is as follows:
A speed measurement sensor is arranged on a conveyor belt, and the speed measurement sensor sends detected information indicating that a speed of the conveyor belt is <NUM> meter/second to ambient searching terminals A, B, and C.

Optionally, the searching terminals A, B, and C measure, by using inertial navigation sensor groups, that moving speeds of the searching terminals are less than or equal to an initial speed of the conveyor belt, and determine that data generated by a wireless signal sent by a measured searched terminal is valid.

The searching terminals separately detect wireless signals sent by ambient searched terminals, form a signal sequence by using detected wireless signals sent by a same searched terminal, and mark a location of a searching terminal for receiving a wireless signal having greatest strength in the signal sequence as a location point. A searched terminal corresponding to the location point is closest to the searching terminal at the location point, and the location point is used to represent a location of the corresponding searched terminal. A time of moving from one location point to another location point may be multiplied by the initial speed of the conveyor belt to obtain a distance between the location points. Assuming that coordinates of one location point are <NUM>, coordinates of the searched terminals detected by the other searching terminals may be computed according to the relative distance. An identifier of a searched terminal and coordinates of a corresponding location point form a location record of the searched terminal. Optionally, the searching terminal may send strength of the wireless signal sent by the detected searched terminal and displacement data of the searching terminal to the server. The server computes a location record of the searched terminal, and forms a location record set.

It is assumed that after computation, a location record sequence of searched terminals detected by a searching terminal A is {<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}, where it is noted that numbers in the brackets represent coordinates in a unit of a meter, and numbers outside the brackets represent identifiers of the searched terminals; a location record sequence of searched terminals detected by a searching terminal B is {<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}, and a location record sequence of searched terminals detected by a searching terminal C is {<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}.

It is assumed that a target searched object for which the searching terminal A needs to search is a searched terminal <NUM>. The searching terminals A, B, and C send the location record sequences of detected searched terminals to the server, to form a location record set M including location records of more searched terminals. According to the method in this embodiment of the present invention, first, the location record sequence of the searched terminals detected by the searching terminal A is added to the location record set M. That is, the location record set M={<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}. The location record sequence of the searched terminals detected by the searching terminal B is checked to find that a searched terminal <NUM> exists in the location record set M, and location records of the searched terminals detected by the searching terminal B are added to M. According to the algorithm Xi=a×xi+(<NUM>-a)×ui in this embodiment of the present invention, where a=<NUM>/<NUM>, new coordinates (<NUM>+<NUM>)/<NUM>=<NUM> of the searched terminal <NUM> may be computed. Coordinates of the other searched objects may be obtained based on the new coordinates of the searched terminal <NUM> by using the algorithms <MAT> and <MAT> in this embodiment of the present invention. The computed new coordinates of the searched terminals in M are updated to the location record set M. That is, M={<NUM>(-<NUM>), <NUM>(-<NUM>), <NUM>(-<NUM>), <NUM>(-<NUM>), <NUM>(-<NUM>), <NUM>(-<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}. Further, conversion into coordinate values is performed. Assuming that maximum values of coordinates are <NUM>, the coordinates need to be converted into values within a range [<NUM>, <NUM>), and the set M={<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)} may be obtained according to a conversion formula. The location record sequence of the searched terminals detected by the searching terminal C is further checked to find that location records of searched terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> exist in the set M, and the location records of the searched terminals detected by the searching terminal are added to the location record set M. The same as the foregoing algorithm, where a=<NUM>/<NUM>, coordinates of the searched terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> may be separately computed and are <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. New coordinates of the other searched terminals in the location record set M may be computed based on the new coordinates of the searched terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> by using the same algorithm, and are updated to the location record set M. That is, M={<NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>), <NUM>(<NUM>)}.

Further, the searching terminals detect wireless signals sent by ambient searched terminals, and send the wireless signals of the detected searched terminals <NUM>, <NUM>, <NUM>, and <NUM> to the server. The server does not have a location record of the searched terminal <NUM>. Therefore, coordinates (<NUM>) of the searching terminal A and coordinates (<NUM>) of a target searched terminal <NUM> are obtained according to coordinates of the searched terminals <NUM>, <NUM>, and <NUM> by means of a centroid method. Therefore, a distance of <NUM> meters between the searching terminal A and the searched terminal <NUM> is computed. The searching terminal notifies the result to the searcher. Optionally, a time of arrival may be computed based on a relative speed (the initial speed of the conveyor belt), and the time is notified to the searcher. Optionally, it indicates that the searched terminal is at a location <NUM> meters from the searcher in a direction departing from the searcher.

It should be noted that the searching terminal in this embodiment has functions of a collection terminal and a searching terminal. When obtaining a location relationship, the searching terminal is the collection terminal described in the foregoing embodiment. When searching for an object, the searching terminal is the searching terminal described above.

In this embodiment of the present invention, coordinates of a location point are obtained based on a measurement result of a relative measurement instrument, and the coordinates of the location point and an identifier of a corresponding searched terminal form a location record, so that a location relationship between multiple searched terminals whose locations are unknown can be determined, and a navigation result can be computed according to the location relationship, thereby reducing costs of deploying and maintaining anchors whose locations are known.

In the foregoing several embodiments, only a two-dimensional plane is considered in most cases. However, in actual application, multiple floors may be involved, to form three-dimensional object searching space. In this case, only a parameter representing a height needs to be added to a coordinate parameter in a location record. Based on the foregoing embodiment of the two-dimensional plane, an embodiment provides a method for measuring displacement in a height direction. Optionally, displacement of a collection terminal in a height direction is measured by using a barometric pressure sensor or an accelerator, and the sensors configured to measure a height may be collectively referred to as a height measurement module. <FIG> shows a barometric pressure change measured when the terminal moves downstairs. Displacement, of the terminal in a height direction, relative to a location point that the terminal previously passes through may be computed based on the barometric pressure change. A concept of the location point is the same as the definition in the foregoing embodiments.

In the method for measuring displacement in a height direction provided in this embodiment, the height measurement module measures the displacement of the terminal in the height direction, to compute a location relationship between terminals in the height direction. With reference to the methods and algorithms in the foregoing embodiments, a location record set representing a location relationship between searched terminals whose locations are unknown in the three-dimensional object searching space can be obtained, to search for an object in the three-dimensional object searching space, thereby reducing costs of deploying and maintaining anchors whose locations are known.

The present invention provides a collection terminal. As shown in <FIG>, the collection terminal <NUM> includes a detection module <NUM>, a first obtaining module <NUM>, a second obtaining module <NUM>, a value assignment module <NUM>, a coordinate obtaining module <NUM>, a generation module <NUM>, a location record sequence forming module <NUM>, and a sending module <NUM>.

The detection module <NUM> is configured to: when the collection terminal <NUM> moves, detect wireless signals sent by ambient searched terminals.

The first obtaining module <NUM> is configured to obtain at least two reference location points according to the wireless signals sent by the ambient searched terminals and detected by the detection module <NUM>. Each reference location point is a location point for obtaining, by the collection terminal, a wireless signal that has greatest strength in multiple wireless signals sent by a corresponding searched terminal.

The second obtaining module <NUM> is configured to: use, as a benchmark location point, either of the at least two reference location points obtained by the first obtaining module <NUM>, and obtain a reference location relationship between the other reference location points and the benchmark location point. The reference location relationship includes a distance between the other reference location points and the benchmark location point and an angle of orientation of the other reference location points relative to the benchmark location point, and the reference location relationship is used to indicate a location relationship between a searched terminal corresponding to the other reference location points and a searched terminal corresponding to the benchmark location point.

The value assignment module <NUM> is configured to: set, as initial coordinates, coordinates of the benchmark location point specified by the second obtaining module <NUM>, and assign values to the initial coordinates.

The coordinate obtaining module <NUM> is configured to compute coordinates of the other reference location points according to the reference location relationship obtained by the second obtaining module <NUM> and the initial coordinates specified by the value assignment unit <NUM>.

The generation module <NUM> is configured to generate one location record for one of the reference location points obtained by the first obtaining module <NUM>. The location record includes coordinates of the reference location point and an identifier of a searched terminal corresponding to the reference location point.

The location record sequence forming module <NUM> is configured to form a location record sequence by using all location records generated by the generation module <NUM>.

The sending module <NUM> is configured to send the location record sequence formed by the location record sequence forming module <NUM> to a third party device. Optionally, the third party device may be a server.

Further, the detection module <NUM> includes a detection unit <NUM> and a determining unit <NUM>. The detection unit <NUM> is configured to: detect the wireless signals sent by the ambient searched terminals, and obtain identifiers of the detected searched terminals and strength of the wireless signals.

The determining unit <NUM> is configured to determine, based on a signal ratio, whether a wireless signal detected by the detection unit <NUM> is a wireless signal sent by the searched terminal.

Further, the determining unit <NUM> is specifically configured to: determine whether a signal ratio of the wireless signal detected by the detection unit <NUM> is greater than or equal to a preset signal ratio threshold; and if the signal ratio of the wireless signal detected by the detection unit <NUM> is greater than or equal to the signal ratio threshold, determine that the wireless signal detected by the detection unit <NUM> is the wireless signal sent by the searched terminal; or if the signal ratio is less than the signal ratio threshold, determine that the wireless signal detected by the detection unit <NUM> is not the wireless signal sent by the searched terminal.

The terminal provided in the present invention records, as the reference location point corresponding to the searched terminal, the location point for obtaining, by the terminal, the wireless signal that has the greatest strength in the wireless signals sent by the searched terminal, the location relationship between the reference location points indicates the location relationship between the corresponding searched terminals, and the location record sequence representing the location relationship between the searched terminals can be obtained based on the location relationship. Therefore, a location relationship between searched terminals whose locations are unknown can be determined, and the location relationship between the searched terminals whose locations are unknown can be determined without deploying anchors whose locations are known, thereby reducing costs of deploying and maintaining anchors.

The present invention provides a device, configured to combine location relationships. As shown in <FIG>, the device <NUM> includes a receiving module <NUM> and a combination module <NUM>.

The receiving module <NUM> is configured to receive at least two location record sequences from a collection terminal. Each location record sequence includes at least two location records, a location record includes coordinates of a reference location point and an identifier of a searched terminal corresponding to the reference location point, and the reference location point is a location point for obtaining a wireless signal that has greatest strength from the searched terminal when the collection terminal moves.

The combination module <NUM> is configured to combine the at least two location record sequences received by the receiving module <NUM> into a location record set in a coordinate system. The location record set includes coordinates of reference location points corresponding to the at least two location records in the coordinate system and identifiers of searched terminals corresponding to the reference location points.

Further, the combination module <NUM> includes a configuration unit <NUM>, an adding unit <NUM>, a first determining unit <NUM>, a temporary location record set unit <NUM>, and a first repetition unit <NUM>.

The configuration unit <NUM> is configured to: configure a location record set, and initialize the location record set as an empty set.

The adding unit <NUM> is configured to add location records in the first location record sequence to the location record set initialized by the configuration unit <NUM>. The first location record sequence is any location record sequence received by the receiving module <NUM>.

The first determining unit <NUM> is configured to: determine whether a location record of at least one searched terminal exists in both a next location record sequence received by the receiving module <NUM> and the location record set; and if the location record of the at least one searched terminal exists in both the next location record sequence and the location record set, combine the next location record sequence with the location record set; or if the location record of the at least one searched terminal does not exist in both the next location record sequence and the location record set, save the next location record sequence into the temporary location record set unit <NUM>.

The first repetition unit <NUM> is configured to: trigger the first determining unit <NUM> to repeat the determining process until the determining process is performed for all location record sequences received by the receiving module <NUM>, and obtain the location record set.

Further, the first determining unit <NUM> includes a first coordinate obtaining subunit <NUM>, a first location record generation subunit <NUM>, a second coordinate obtaining subunit <NUM>, a second location record generation subunit <NUM>, a third coordinate obtaining subunit <NUM>, a third location record generation subunit <NUM>, and a first replacing subunit <NUM>.

The first coordinate obtaining subunit <NUM> is configured to obtain first coordinates according to coordinates corresponding to a first searched terminal in the next location record sequence received by the receiving module <NUM> and coordinates in the location record set. The first searched terminal is a searched terminal that exists in both the next location record sequence received by the receiving module <NUM> and the location record set.

The first location record generation subunit <NUM> is configured to generate a first location record for the first searched terminal. The first location record includes the first coordinates obtained by the first coordinate obtaining subunit <NUM> and an identifier of the searched terminal.

The second coordinate obtaining subunit <NUM> is configured to obtain second coordinates according to the first coordinates obtained by the first coordinate obtaining subunit <NUM> and coordinates corresponding to a first remaining searched terminal in the next location record sequence received by the receiving module <NUM>. The first remaining searched terminal is a searched terminal other than the searched terminal in the next location record sequence received by the receiving module <NUM>.

The second location record generation subunit <NUM> is configured to generate a second location record for the first remaining searched terminal. The second location record includes the second coordinates obtained by the second coordinate obtaining subunit <NUM> and an identifier of the first remaining searched terminal.

The third coordinate obtaining subunit <NUM> is configured to obtain third coordinates according to the first coordinates obtained by the first coordinate obtaining subunit <NUM> and coordinates corresponding to a second remaining searched terminal in the location record set. The second remaining searched terminal is a searched terminal other than the searched terminal in the location record set.

The third location record generation subunit <NUM> is configured to generate a third location record for the second remaining searched terminal. The third location record includes the third coordinates obtained by the third coordinate obtaining subunit <NUM> and an identifier of the second remaining searched terminal.

The first replacing subunit <NUM> is configured to replace location records in the location record set with all the first location record generated by the first location record generation subunit <NUM>, the second location record generated by the second location record generation subunit <NUM>, and the third location record generated by the third location record generation subunit <NUM>.

Further, the device <NUM> further includes a location record set updating module <NUM>, configured to update the location record set.

The location record set updating module <NUM> includes a second determining unit <NUM> and a second repetition unit <NUM>.

The second determining unit <NUM> is configured to: determine whether a location record of at least one searched terminal exists in both a location record sequence stored in the temporary location record set unit <NUM> and the location record set; and if the location record of the at least one searched terminal exists in both the location record sequence stored in the temporary location record set unit <NUM> and the location record set, combine the location record sequence with the location record set; or if the location record of the at least one searched terminal does not exist in both the location record sequence stored in the temporary location record set unit <NUM> and the location record set, re-save the location record sequence into the temporary location record set unit <NUM>.

The second repetition unit <NUM> is configured to: trigger the second determining unit <NUM> to repeat the determining process until the determining process is performed for all location record sequences stored in the temporary location record set unit, and obtain an updated location record set.

Further, the second determining unit <NUM> includes a fourth coordinate obtaining subunit <NUM>, a fourth location record generation subunit <NUM>, a fifth coordinate obtaining subunit <NUM>, a fifth location record generation subunit <NUM>, a sixth coordinate obtaining subunit <NUM>, a sixth location record generation subunit <NUM>, and a second replacing subunit <NUM>.

The fourth coordinate obtaining subunit <NUM> is configured to obtain fourth coordinates according to coordinates corresponding to a second searched terminal in the location record sequence stored in the temporary location record set unit <NUM> and coordinates in the location record set. The second searched terminal is a searched terminal that exists in both the location record sequence stored in the temporary location record set unit <NUM> and the location record set.

The fourth location record generation subunit <NUM> is configured to generate a fourth location record for the second searched terminal. The fourth location record includes the fourth coordinates obtained by the fourth coordinate obtaining subunit <NUM> and an identifier of the searched terminal.

The fifth coordinate obtaining subunit <NUM> is configured to obtain fifth coordinates according to the fourth coordinates obtained by the fourth coordinate obtaining subunit <NUM> and coordinates corresponding to a third remaining searched terminal in the location record sequence stored in the temporary location record set unit <NUM>. The third remaining searched terminal is a searched terminal other than the searched terminal in the location record sequence stored in the temporary location record set unit <NUM>.

The fifth location record generation subunit <NUM> is configured to generate a fifth location record for the third remaining searched terminal. The fourth location record includes the fifth coordinates obtained by the fifth coordinate obtaining subunit <NUM> and an identifier of the third remaining searched terminal.

The sixth coordinate obtaining subunit <NUM> is configured to obtain sixth coordinates according to the fourth coordinates obtained by the fourth coordinate obtaining subunit <NUM> and coordinates corresponding to a fourth remaining searched terminal in the location record set. The fourth remaining searched terminal is a searched terminal other than the searched terminal in the location record set.

The sixth location record generation subunit <NUM> is configured to generate a sixth location record for the fourth remaining searched terminal. The sixth location record includes the sixth coordinates obtained by the sixth coordinate obtaining subunit <NUM> and an identifier of the fourth remaining searched terminal.

The second replacing subunit <NUM> is configured to replace location records in the location record set with all the fourth location record generated by the fourth location record generation subunit <NUM>, the fifth location record generated by the fifth location record generation subunit <NUM>, and the sixth location record generated by the sixth location record generation subunit <NUM>.

The device provided in this embodiment of the present invention combines the received location record sequence according to a standard that the location record including the identifier of the searched terminal exists in both the received location record sequence and the location record set, to obtain the location record set, so that multiple location record sequences are combined into one location record set.

An embodiment of the present invention provides a searching terminal. As shown in <FIG>, the searching terminal <NUM> includes a sending module <NUM>, a detection module <NUM>, a receiving module <NUM>, a first obtaining module <NUM>, a second obtaining module <NUM>, a coordinate obtaining module <NUM>, a navigation path obtaining module <NUM>, and a navigation module <NUM>.

The sending module <NUM> is configured to send a request for searching for a target searched terminal to a server (or a third party device). The request is used to trigger the server to send a location record set, the location record set includes at least two location records, a location record includes coordinates of a reference location point and an identifier of a searched terminal corresponding to the reference location point, and the reference location point is a location point for obtaining a wireless signal that has greatest strength from the searched terminal when a collection terminal moves.

The detection module <NUM> is configured to: detect a wireless signal sent by an ambient searched terminal, and obtain an identifier of the detected searched terminal and strength of the wireless signal. The target searched terminal is one of the searched terminal.

The receiving module <NUM> is configured to receive the location record set sent by the server.

The first obtaining module <NUM> is configured to: search the location record set received by the receiving module <NUM> for a target location record, and obtain coordinates in the target location record. The target location record is a location record including an identifier of the target searched terminal.

The second obtaining module <NUM> is configured to: search the location record set received by the receiving module <NUM> for a reference location record, and obtain coordinates in the reference location record. The reference location record is a location record including the identifier of the searched terminal detected by the searching terminal.

The coordinate obtaining module <NUM> is configured to: compute coordinates of the searching terminal according to the coordinates obtained by the second obtaining module <NUM>, or compute coordinates of the searching terminal according to the coordinates obtained by the second obtaining module <NUM> and the strength of the wireless signal detected by the detection module <NUM>.

The navigation path obtaining module <NUM> is configured to compute a navigation path according to the coordinates of the searching terminal obtained by the coordinate obtaining module <NUM> and the coordinates obtained by the first obtaining module <NUM>.

The navigation module <NUM> is configured to search for the target searched terminal according to the navigation path obtained by the navigation path obtaining module <NUM>.

Further, the detection module <NUM> includes: a detection unit <NUM> and a determining unit <NUM>.

The detection unit <NUM> is configured to: detect the wireless signal sent by the ambient searched terminal, and obtain the identifier of the detected searched terminal and the strength of the wireless signal.

Further, the determining unit <NUM> is specifically configured to: determine whether a signal ratio of the wireless signal detected by the detection unit <NUM> is greater than or equal to a preset signal ratio threshold; and
if the signal ratio of the wireless signal detected by the detection unit <NUM> is greater than or equal to the signal ratio threshold, determine that the wireless signal detected by the detection unit <NUM> is the wireless signal sent by the searched terminal; or if the signal ratio is less than the signal ratio threshold, determine that the wireless signal detected by the detection unit <NUM> is not the wireless signal sent by the searched terminal.

Optionally, the coordinate obtaining module <NUM> is specifically configured to compute the coordinates (Xi, Yi) of the searching terminal according to <MAT> and <MAT>. The coordinates obtained by the second obtaining module <NUM> are (xi, yi), and n is a quantity of coordinates obtained by the second obtaining module <NUM>.

Optionally, the coordinate obtaining module <NUM> is specifically configured to compute the coordinates (Xi, Yi) of the searching terminal according to <MAT> and <MAT>. The coordinates obtained by the second obtaining module <NUM> are (xi, yi), Pi (dBm) is the strength of the wireless signal detected by the detection module <NUM>, and n is a quantity of coordinates obtained by the second obtaining module <NUM>.

In this embodiment of the present invention, based on a feature that a location relationship between searched objects is stable, a stable location relationship is converted into a location relationship set including coordinates and identifiers, coordinates of a target searched object and coordinates of a searcher may be obtained according to the location relationship set, and a navigation path is then computed according to the coordinates of the target searched object and the coordinates of the searcher, so that the target object can be found quickly and simply when location information of the searched object and location information of the searcher cannot be determined. In the object searching method provided in this embodiment of the present invention, no anchor whose location is known needs to be deployed, thereby reducing costs of deploying and maintaining anchors.

An embodiment of the present invention provides a server. As shown in <FIG>, the server <NUM> includes a receiving module <NUM>, a first coordinate obtaining module <NUM>, a second coordinate obtaining module <NUM>, a navigation path obtaining module <NUM>, and a sending module <NUM>.

The receiving module <NUM> is configured to receive an object searching request sent by a searching terminal for searching for a target searched terminal. The object searching request carries an identifier of the target searched terminal.

The first coordinate obtaining module <NUM> is configured to obtain coordinates of the searching terminal.

The second coordinate obtaining module <NUM> is configured to: search a location record set for a target location record according to the identifier of the target searching terminal received by the receiving module <NUM>, and obtain coordinates in the target location record. The location record set includes at least two location records, a location record includes coordinates of a reference location point and an identifier of a searched terminal corresponding to the reference location point, the reference location point is a location point for obtaining a wireless signal that has greatest strength from the searched terminal when a collection terminal moves, and the target location record is a location record including the identifier of the target searched terminal.

The navigation path obtaining module <NUM> is configured to compute a navigation path according to the coordinates obtained by the first coordinate obtaining module <NUM> and the coordinates obtained by the second coordinate obtaining module <NUM>.

The sending module <NUM> is configured to send the navigation path obtained by the navigation path obtaining module <NUM> to the searching terminal.

Optionally, the first coordinate obtaining module <NUM> is specifically configured to obtain the coordinates of the searching terminal from the searching terminal.

Optionally, the first coordinate obtaining module <NUM> includes a reference coordinate obtaining unit <NUM> and a coordinate obtaining unit <NUM>.

The reference coordinate obtaining unit <NUM> is configured to: search the location record set for a reference location record, and obtain coordinates in the reference location record. The reference location record is a location record that is received by the receiving module <NUM> and that includes an identifier of the searched terminal that is detected when the searching terminal sends the object searching request.

The coordinate obtaining unit <NUM> is configured to: compute the coordinates of the searching terminal according to the coordinates obtained by the reference coordinate obtaining unit <NUM>, or compute the coordinates of the searching terminal according to the coordinates obtained by the reference coordinate obtaining unit <NUM> and strength that is received by the receiving module <NUM>, that is of a wireless signal sent by the searched terminal, and that is detected when the searching terminal sends the object searching request.

Further, the coordinate obtaining unit <NUM> is specifically configured to compute the coordinates (Xi, Yi) of the searching terminal according to <MAT> and <MAT> , where the coordinates obtained by the reference coordinate obtaining unit <NUM> are (xi, yi), and n is a quantity of coordinates obtained by the reference coordinate obtaining unit <NUM>; or
compute the coordinates (Xi, Yi) of the searching terminal according to <MAT> and <MAT> , where the coordinates obtained by the reference coordinate obtaining unit <NUM> are (xi, yi), Pi (dBm) is the strength of the wireless signal detected by the searching terminal and received by the receiving module <NUM>, and n is a quantity of coordinates obtained by the reference coordinate obtaining unit <NUM>.

An embodiment of the present invention provides an application scenario of searching for a car in a parking lot. An owner A drives a car B to enter a parking lot C, and parks the car B in the parking lot. The owner A leaves the parking lot for a time period and returns to the parking lot to search for the car B. In an actual scenario, especially in a strange parking lot, even if there are instruction icons and codes in the parking lot, it is not easy for the owner to quickly find the car. This embodiment of the present invention provides a method for searching for a car. Specific details are as follows.

After entering the parking lot, the owner A turns on the searching terminal to search for the object. During actual implementation, the object searching method may be specifically a car searching APP in a collection terminal. For example, a mobile phone onto which a car searching APP is installed is a searching terminal.

The location record set in this embodiment is obtained by using the location record sequence provided in the foregoing embodiments and a method for combining multiple location record sequences. Optionally, in a process in which the owner searches for the owner's car, the searching terminal may be used as a collection terminal and implements, on the background, the functions of the collection terminal described in the foregoing embodiments, to provide data for obtaining and updating of the location record set. Optionally, a robot that moves in the parking lot regularly and is equivalent to a collection terminal obtains and updates the location record set. For example, a track for the collection robot is deployed in the parking lot, and the robot moves in the parking lot along a preset track every a time period, to implement functions of the collection terminal.

In this embodiment of the present invention, a device that can transmit a wireless signal and is placed or installed on the car, a searching terminal (or a collection terminal onto which an object searching APP is installed) carried by a searcher, and a collection terminal (a robot, or a searching terminal carried by a searcher) form an object searching system. A location relationship between cars parked in the parking lot is determined by using wireless signals, and the location relationship is further converted into a location record set including coordinates and identifiers of wireless signals sent by the cars. Coordinates indicating the searching terminal and coordinates indicating a target searched car (that is, coordinates in a location record including an identifier of a wireless signal sent by the target searched car) are obtained based on the location record set. A navigation path is computed by using the coordinates of the searching terminal and the coordinates of the target searched car, so that the target searched car parked in the parking lot can be found quickly without deploying anchors whose locations are known, thereby reducing costs of deploying and maintaining devices whose locations are known.

In another actual application scenario, an embodiment of the present invention provides a method for searching for a container. Specifically, before being placed in a storage area of a harbor, each container is provided with a device that can transmit a wireless signal carrying an identifier. The identifier is used to identify a corresponding container. The device may be a wireless transceiver, a radio frequency card, a Bluetooth device, an infrared device, or the like.

Certainly, step <NUM> and step <NUM> may be replaced with the following: The searching terminal does not send the identifier and the signal strength of the wireless signal obtained by scanning the ambient container to the server, but requests the server to send the stored location record set to the searching terminal; the searching terminal obtains the coordinates of the searching terminal and the coordinates of the target searched container according to the method for obtaining, by the server, the coordinates of the searching terminal and the coordinates of the target searched container, computes the navigation path based on the coordinates of the searching terminal and the coordinates of the target searched container, and searches for the target searched container according to the navigation path.

In this embodiment of the present invention, a location relationship between containers is converted into a location record set, coordinates of a searcher (a searching terminal) and coordinates of a target searched container are obtained in the location record set, and a navigation path is computed according to the coordinates, so that the target searched container in the storage area can be found quickly without deploying anchors whose locations are known, thereby reducing costs of deploying and maintaining devices whose locations are known.

Claim 1:
An object searching method, comprising:
receiving (<NUM>) an object searching request sent by a searching terminal for searching for a target searched terminal, wherein the object searching request carries an identifier of the target searched terminal, wherein: the searching terminal is a device carried by a searcher and having a function of receiving and transmitting wireless signals, a searched terminal is a device that is arranged on a searched object and at least can send an identifiable wireless signal, and a target searched terminal is a device that is arranged on an object that a searcher is to search for and at least can send an identifiable wireless signal;
obtaining (<NUM>) coordinates of the searching terminal;
searching (<NUM>) a location record set for a target location record according to the identifier of the target searched terminal, and obtaining coordinates in the target location record, wherein the location record set comprises at least two location records, each location record comprises coordinates of a reference location point and an identifier of a searched terminal corresponding to the reference location point, the reference location point is a location point where a wireless signal that has greatest strength from the searched terminal is obtained when a collection terminal moves, and the target location record is a location record comprising the identifier of the target searched terminal, wherein a collection terminal is a device that has a function of receiving and transmitting wireless signals and is equipped with an inertial navigation sensor group;
computing (<NUM>) a navigation path according to the coordinates of the searching terminal and the coordinates in the target location record; and
sending (<NUM>) the navigation path to the searching terminal.