Secure distance measurement positioning method for private coordinates

Abstract

A secure ranging and positioning method for private coordinates comprises the following steps: step 1, a user constructs a confusion circuit and a random confusion sequence, and sends the confusion circuit and the random confusion sequence to a central server; step 2, the central server sends front communication data to each base station, and each base station sets a confusion value by using ranging information, constructs a private polynomial by using own private coordinate information and sends the private polynomial to other base stations; 3, each base station performs data fusion on the private polynomials from other base stations, and a crowdsourcing data set spliced by a fused value and a self-confusion value is sent to a central server; and step 4, the server evaluates the obfuscation circuit, calculates the sum value of the position information of the base station, and sends a result to the user, and the user solves to obtain own coordinates. By means of the method, the safe distance measurement positioning method for the private coordinates is good in safety and high in positioning precision.

Description

Technical Field

[0001] The present invention relates to the technical field of radio ranging and positioning, and in particular to a secure ranging and positioning method for private coordinates. Background Art

[0002] In recent years, location information services have been widely used in many fields such as navigation, social networking, logistics, intelligent transportation, and unmanned driving, greatly promoting the development of various data applications based on geographic location. Existing positioning methods usually rely on the distance measurement or signal strength between the base station and the user device to calculate the user's coordinates. Although these methods have certain advantages in positioning accuracy, they face two major problems: first, the user's coordinates may be directly obtained by the base station, resulting in privacy leakage; second, during the positioning process, the coordinates of each base station need to be exchanged with each other, and there is a risk of being intercepted and leaked by other base stations or users. These problems not only affect the privacy security of users, but also challenge the trust mechanism of the positioning system.

[0003] However, existing ranging and positioning methods often use noise addition mechanisms to protect the private coordinates of users and base stations, sacrificing positioning accuracy and making it difficult to balance user experience and privacy protection requirements. At the same time, existing ranging and positioning solutions based on encryption technology have deficiencies in computational complexity and communication overhead, resulting in a significant decrease in the efficiency of the positioning system.

[0004] Therefore, studying the privacy protection technology and positioning algorithm optimization strategy in private coordinate positioning and designing a real-time and effective private coordinate secure positioning method are of great significance to improving the security, accuracy and computational efficiency of location information services. Summary of the invention

[0005] In order to solve the problem that the existing ranging and positioning system has insufficient protection strength for private coordinates, resulting in the coordinate information of users and base stations being easily leaked during the positioning process, the present invention provides a secure ranging and positioning method for private coordinates.

[0006] The technical solution adopted by the present invention is as follows: a method for secure ranging and positioning of private coordinates, the steps of which are:

[0007] Step 1: The user constructs a confusion circuit and a random confusion sequence and sends them to the central server;

[0008] Step 1-1 The user builds the obfuscated circuit:

[0009] Assume that in an indoor positioning system based on ranging, the user obtains The distance between them is used to locate, i = 1, 2, ..., N. Before starting a positioning, the user builds a confusion circuit Circuit acceptance list Φ=[φ1,…,φN ] and the list Ψ=[ψ1,…,ψ N ] as parameters, both of which contain N values ​​of size M, where M is the maximum bit length of the distance. The circuit is calculated by adding the corresponding elements of the two lists and then returning the sum of the calculated results, that is,

[0010]

[0011] Step 1-2 User sets the obfuscation sequence:

[0012] The user generates N random values ​​θ that he / she holds in secret i , and then generate the confusion sequence according to the confusion circuit structure

[0013] Among them, each All are θ i Obfuscated version of

[0014] Step 1-3 The user will confuse the circuit structure and confusion sequence Sent to the server.

[0015] Step 2: The central server sends the pre-communication data to each base station. Each base station uses the ranging information to set the confusion value, uses its own private coordinate information to construct a private polynomial and sends it to other base stations.

[0016] Step 2-1 The central server sends pre-communication data to each base station:

[0017] The server generates a random sequence Δ=[δ1,...,δ N ] and stored in the stack, and assigned to the base station at the beginning of a positioning;

[0018] Step 2-2 Each base station sets the confusion value:

[0019] Let the user's location be (x, y) and the location of the i-th base station be (x i ,y i ), The distance between the i-th base station and the base station is d i , the i-th base station obtains The confusion value

[0020] in: Reflects the ranging information between the i-th base station and the user, α i =[-2x i ,-2y i ,1] T Contains the private coordinate information of the i-th base station;

[0021] Step 2-3 Each base station constructs a private polynomial:

[0022] Base station i constructs N-1 N-1 degree polynomials as

[0023]

[0024] Where j = 1, 2, ..., N and j ≠ i, From the integer ring is a randomly selected value in and is kept secret by base station i;

[0025] Step 2-4 Base station i constructs the private polynomial The value of is sent to base station j.

[0026] Step 3: Each base station performs data fusion on the private polynomials from other base stations, and sends the crowdsourcing data set composed of the fused value and its own obfuscated value to the central server;

[0027] Step 3-1 Each base station performs data fusion:

[0028] After base station i obtains the polynomial values ​​generated by other N-1 base stations, it performs data fusion on all polynomial values:

[0029]

[0030] Step 3-2 Base station i will and i The value is sent to the central server.

[0031] Step 4: The server evaluates the confusion circuit and calculates the sum of the base station location information, and sends the result to the user, who solves it to obtain his own coordinates.

[0032] Step 4-1 Server evaluates the obfuscated circuit:

[0033] Before the server starts evaluating the obfuscation circuit, it receives the obfuscation value from each base station and obtains the obfuscation input

[0034]

[0035] Server uses input and Perform the garbled circuit calculation and obtain the calculation result

[0036]

[0037] Step 4-2: the server calculates the sum of base station location information;

[0038] The server uses the polynomial fusion values ​​received from each base station to solve the simultaneous equations and obtain

[0039] Step 4-3 The server will The value of is sent to the user;

[0040] Step 4-4 The user solves his own coordinates:

[0041] The user uses the value sent by the server and the random value held by itself to calculate:

[0042]

[0043] The user uses the first element of the calculation result as its own horizontal coordinate and the second element as its own vertical coordinate.

[0044] The beneficial effects created by the present invention are as follows: the present invention proposes a private coordinate positioning method based on a ranging environment, adopts secret sharing technology to ensure that the coordinate information between base stations is kept confidential, and combines obfuscation circuit technology to confuse user coordinate information to prevent private coordinate information from being intercepted by other base stations or users, thereby effectively protecting the location information of all members participating in the positioning and avoiding potential privacy and security issues. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 :It is a flow chart of the secure ranging and positioning method of private coordinates of the present invention;

[0046] Figure 2 : Schematic diagram of ranging and positioning network communication. DETAILED DESCRIPTION

[0047] The following will be combined with the accompanying drawings in the embodiments of the present invention to fully describe the private coordinate ranging and positioning method of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Embodiment 1:

[0049] like Figure 1-2 An example of the present invention proposes a secure ranging positioning method for private coordinates. Assume that an indoor positioning system based on ranging is based on the following premise:

[0050] 1. The experimental area is a limited plane area, and the base stations are evenly distributed in the area. During the experiment, the user movement in this area will be simulated.

[0051] 2. Each user's location information includes the cluster to which they belong, MAC address, pseudo serial number, and the actual horizontal and vertical coordinates to ensure that privacy information is isolated from the actual location data.

[0052] 3. The distance measurement between the user and the base station is recorded by the base station's ranging array to ensure that the distance data between each user and all base stations is accurately stored.

[0053] like Figure 2 As shown, taking any user as an example, assuming that the user's position is (x, y) and the position of the i-th base station is (x i ,y i ), The distance between the i-th base station and the base station measured by some method (such as based on arrival time, based on flight time, etc.) is d i , i=1,2,…,N, we can get the following equation:

[0054]

[0055] make

[0056]

[0057] Assuming that the noise in the system is Gaussian white noise, the user position estimation value is obtained by using the maximum likelihood estimation method:

[0058] In order to prevent the coordinate information of the user and the base station from being leaked during the positioning process, the present invention uses a secure multi-party computing method to perform secure ranging and positioning.

[0059] First, before positioning begins, the user builds an obfuscation circuit in advance, in accordance with the background processing strategy of the mobile operating system. The circuit accepts two input lists Φ and Ψ as parameters. The circuit's calculation process mainly involves adding the corresponding elements of the two lists and finally returns the sum of the calculation results, that is:

[0060]

[0061] The user then generates N random values ​​θ that he / she holds in secret i , these random values ​​are used to construct the obfuscation sequence to ensure that the input data cannot be directly accessed. According to the structure of the obfuscated circuit, the generated obfuscation sequence can be expressed as:

[0062]

[0063] The server pregenerates a random sequence Δ=[δ1,...,δ N ] and store it in the stack, and receive and Then, Δ is sent to each base station.

[0064] After receiving Δ, base station i obtains it through the One-Time Pad (OTP) protocol for evaluation The confusion value in Reflects the ranging information between the i-th base station and the user, α i =[-2x i ,-2y i ,1] T

[0065] Base station i also constructs N-1 polynomials:

[0066]

[0067] Where j = 1, 2, ..., N and j ≠ i, From the integer ring is a randomly selected value in and is kept secret by base station i;

[0068] Base station i will construct the private polynomial The value of is sent to base station j, and data fusion is performed on all polynomial values:

[0069]

[0070] and will and i The value is sent to the central server:

[0071] Before the server starts evaluating the obfuscation circuit, it first receives the obfuscation values ​​from each base station and obtains the obfuscation input from them. The obfuscation input can be expressed as:

[0072]

[0073] The server then uses the obfuscated input received from the base station and user-generated obfuscated input To perform the garbled circuit calculation. The calculation result is expressed as:

[0074]

[0075] The server constructs the following set of equations using the polynomial fusion values ​​received from each base station:

[0076]

[0077] By solving the simultaneous equations, the server can finally obtain the matrix The value of .

[0078] The server will calculate the sum of The values ​​are sent to the user. After receiving these values, the user combines the random values ​​he holds to calculate:

[0079]

[0080] The user calculates the Contains three elements, the first element represents the user's horizontal coordinate, and the second element represents the user's vertical coordinate.

[0081] Finally, the user obtains his own positioning results, including accurate horizontal and vertical coordinates, which are used to indicate his specific position in a certain space.

[0082] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A secure distance measurement and positioning method for private coordinates, characterized in that: The steps are: Step 1: The user constructs a confusion circuit and a random confusion sequence and sends them to the central server; Step 2: The central server sends the pre-communication data to each base station. Each base station uses the ranging information to set the confusion value, uses its own private coordinate information to construct a private polynomial and sends it to other base stations. Step 3: Each base station performs data fusion on the private polynomials from other base stations, and sends the crowdsourcing data set composed of the fused value and its own obfuscated value to the central server; Step 4: The server evaluates the confusion circuit and calculates the sum of the base station location information, and sends the result to the user, who solves it to obtain his own coordinates.

2. A secure distance measurement and positioning method for private coordinates according to claim 1, characterized in that: In the step 1, the specific method is: Step 1-1 The user builds the obfuscated circuit: Assume that in an indoor positioning system based on ranging, the user obtains The distance between them is used to locate, i = 1, 2, ..., N. Before starting a positioning, the user builds a confusion circuit Circuit acceptance list Φ = [φ1, ..., φ N ] and the list Ψ = [ψ1, ..., ψ N ] as parameters, both of which contain N values ​​of size M, where M is the maximum bit length of the distance. The circuit is calculated by adding the corresponding elements of the two lists and then returning the sum of the calculated results, that is, Step 1-2 User sets the obfuscation sequence: The user generates N random values ​​θ that he / she holds in secret i , and then generate the confusion sequence according to the confusion circuit structure Among them, each All are θ i Obfuscated version of Step 1-3 The user will confuse the circuit structure and confusion sequence Sent to the server.

3. The method for secure ranging and positioning of private coordinates according to claim 1, characterized in that: In the step 2, the specific method is: Step 2-1 The central server sends pre-communication data to each base station: The server generates a random sequence Δ = [δ1, ..., δ N ] and stored in the stack, and assigned to the base station at the beginning of a positioning; Step 2-2 Each base station sets the confusion value: Let the user's position be (x, y) and the position of the i-th base station be (x i ,y i ), The distance between the i-th base station and the base station is d i , the i-th base station obtains The confusion value in: Reflects the ranging information between the i-th base station and the user, α i =[-2x i , -2y i , 1] T Contains the private coordinate information of the i-th base station; Step 2-3 Each base station constructs a private polynomial: Base station i constructs N-1 N-1 degree polynomials as Where j = 1, 2, ..., N and j ≠ i, From the integer ring is a randomly selected value in and is kept secret by base station i; Step 2-4 Base station i constructs the private polynomial The value of is sent to base station j.

4. The method for secure ranging and positioning of private coordinates according to claim 1, characterized in that: In the step 3, the specific method is: Step 3-1 Each base station performs data fusion: After base station i obtains the polynomial values ​​generated by other N-1 base stations, it performs data fusion on all polynomial values: Step 3-2 Base station i will and E i The value is sent to the central server.

5. The method for secure ranging and positioning of private coordinates according to claim 1, characterized in that: In the step 4, the specific method is: Step 4-1 Server evaluates the obfuscated circuit: Before the server starts evaluating the obfuscation circuit, it receives the obfuscation value from each base station and obtains the obfuscation input Server uses input and Perform the garbled circuit calculation and obtain the calculation result Step 4-2: The server calculates the sum of base station location information; The server uses the polynomial fusion values ​​received from each base station to solve the simultaneous equations and obtain Step 4-3 The server will The value of is sent to the user; Step 4-4 The user solves his own coordinates: The user uses the value sent by the server and the random value held by itself to calculate: The user uses the first element of the calculation result as its own horizontal coordinate and the second element as its own vertical coordinate.

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