CN110730453B

CN110730453B - Wireless body area network, key generation method, key distribution method and related device thereof

Info

Publication number: CN110730453B
Application number: CN201910893081.5A
Authority: CN
Inventors: 孙方敏; 李烨
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2022-03-04
Anticipated expiration: 2039-09-20
Also published as: CN110730453A

Abstract

The embodiment of the application is suitable for the technical field of computer science and application, and discloses a wireless body area network, a key generation method, a key distribution method and a related device thereof.

Description

Wireless body area network, key generation method, key distribution method and related device thereof

Technical Field

The present application relates to the field of computer science and application technology, and in particular, to a key generation method, a key distribution method, and a computer-readable storage medium for a wireless body area network, a coordinator node, a wearable device, and a wireless body area network.

Background

With the rapid development of wireless body area networks, more and more wearable devices are applied to various aspects of life, including personal health management, mobile payment, tracking and positioning, social and entertainment, and the like.

In a wireless body area network, data collected and transmitted by wearable equipment has the requirements of privacy and high safety. In addition, the wearable device has limited energy and computational resources due to small volume, and the traditional data transmission safety method is not suitable for the wearable device with limited resources; the security level of the network security method for the large-scale sensor network cannot meet the security application requirements of the wearable device.

At present, the security and consistency of key distribution of a wireless body area network are poor, the calculation is very complex, more calculation resources need to be consumed, and the method is not suitable for wearable equipment with limited resources.

Disclosure of Invention

Embodiments of the present application provide a wireless body area network, a coordinator node, a wearable device, a key generation method, an allocation method, and a computer-readable storage medium for a wireless body area network, so as to solve the problems of poor security and consistency of key allocation and more resource consumption of the existing wireless body area network.

In a first aspect, an embodiment of the present application provides a wireless body area network, where the wireless body area network includes a coordinator node and at least one wearable device communicatively connected to the coordinator node, and both the coordinator node and the wearable device are integrated with an acceleration acquisition device;

the coordinator node is used for sending a data acquisition synchronization message to the wearable device; acquiring a first step state acceleration signal; extracting first gait common information in the first step state acceleration signal; generating key encryption information according to the key to be distributed and the first gait common information; sending the key encryption information to the wearable device;

the wearable device is used for receiving the data acquisition synchronization message and synchronously acquiring a second-step acceleration signal according to the data acquisition synchronization message; extracting second gait common information in the second step state acceleration signal; receiving the key encryption information; decrypting the key encryption information according to the second gait common information to obtain the key to be distributed;

the first gait common information is position information of a peak value and a valley value of the first step state acceleration signal; the second gait common information is position information of a peak value and a valley value of the second step state acceleration signal.

Therefore, the gait acceleration signals are synchronously acquired through the acceleration acquisition devices respectively integrated by the coordinator and the wearable equipment, the position information of the peak value and the valley value in the gait acceleration signals is correspondingly extracted to serve as the gait common information, the gait common information is used for carrying out key distribution of the wireless body area network, the safety and the consistency are high, the calculation is simple, and the method is suitable for the wearable equipment with limited resources.

Specifically, the extraction process of the position information of the peak value and the valley value of the gait acceleration signal is simpler and more convenient, so that the calculation resources consumed in the key distribution process of the wireless body area network are less, and the method is suitable for resource-limited wearable equipment. In the key distribution process, the position information is used as the gait common information for encryption and decryption, the security is high, only the coordinator node is needed to generate the key, the gait common information shared by the coordinator node and the wearable device is used for key distribution, and the consistency is high.

With reference to the first aspect, in a possible implementation manner, the coordinator node is specifically configured to:

and generating the key to be distributed according to the noise signal in the first step state acceleration signal.

It should be noted that, in the embodiment of the present application, the generation manner of the key to be distributed may be arbitrary, and compared with other manners, the generation manner of the key to be distributed through the noise signal in the gait acceleration signal may improve randomness and information entropy of the key.

In a second aspect, an embodiment of the present application provides a key distribution method for a wireless body area network, which applies a coordinator node of the wireless body area network, where the coordinator node is integrated with an acceleration acquisition device, and the coordinator node is in communication connection with at least one wearable device; the method comprises the following steps:

sending a data acquisition synchronization message to the wearable device, wherein the data acquisition synchronization message is used for indicating the wearable device to synchronously acquire second-step acceleration signals;

acquiring a first step state acceleration signal;

extracting first gait common information in the first step state acceleration signal;

generating key encryption information according to the key to be distributed and the first gait common information;

sending the key encryption information to the wearable device to indicate the wearable device to decrypt the key encryption information according to second gait common information extracted from the second step acceleration signal to obtain the key to be distributed;

In a third aspect, an embodiment of the present application provides a key distribution method for a wireless body area network, which is applied to a wearable device of the wireless body area network, where the wearable device is integrated with an acceleration acquisition device, and the wearable device is in communication connection with a coordinator node; the method comprises the following steps:

receiving a data acquisition synchronization message sent by the coordinator node;

synchronously acquiring a second-step state acceleration signal according to the data acquisition synchronization message;

extracting second gait common information in the second step state acceleration signal;

receiving the key encryption information sent by the coordinator node, wherein the key encryption information is generated by the coordinator node according to first gait common information extracted from the collected first step acceleration signal and a key to be distributed;

decrypting the key encryption information according to the second gait common information to obtain the key to be distributed;

In a fourth aspect, an embodiment of the present application provides a key generation method for a wireless body area network, which is applied to a coordinator node of the wireless body area network, where the coordinator node is integrated with an acceleration acquisition device, and the method includes:

acquiring a first step state acceleration signal;

extracting a noise signal in the first step state acceleration signal;

and generating a key to be distributed according to the noise signal.

In a fifth aspect, an embodiment of the present application provides a coordinator node, including an acceleration acquisition device, a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor, when executing the computer program, implements the method according to any one of the second or fourth aspects.

In a sixth aspect, embodiments of the present application provide a wearable device, including an acceleration acquisition apparatus, a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor, when executing the computer program, implements the method according to any one of the third aspects.

In a seventh aspect, this application provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the computer program implements the method according to the second aspect or any one of the above fourth aspects.

In an eighth aspect, the present application provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the computer program implements the method according to any one of the third aspects.

In a ninth aspect, embodiments of the present application provide a computer program product, which when run on a coordinator node, causes the coordinator node to perform the method of any one of the second or fourth aspects described above.

In a tenth aspect, embodiments of the present application provide a computer program product, which, when run on a wearable device, causes the wearable device to perform the method of any of the third aspects described above.

It is to be understood that the beneficial effects of the second to tenth aspects can be seen from the description of the first aspect, and are not repeated herein.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic block diagram of a system architecture of a wireless body area network according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a signed window code provided in an embodiment of the present application;

fig. 3 is a schematic diagram of a zero-phase filtering process provided in an embodiment of the present application;

FIG. 4 is a schematic diagram of noise signal-based coding according to an embodiment of the present disclosure;

fig. 5 is a schematic block diagram of a flow chart of a key distribution method for a wireless body area network according to an embodiment of the present application;

fig. 6 is a schematic block diagram of a process for generating a key to be distributed according to a noise signal according to an embodiment of the present application;

fig. 7 is a schematic block diagram of a flow chart of a key distribution method for a wireless body area network according to an embodiment of the present application;

fig. 8 is a schematic block diagram of a flowchart of a key generation method for a wireless body area network according to an embodiment of the present application;

fig. 9 is a schematic diagram of an interaction between a coordinator node and a wearable device according to an embodiment of the present application;

fig. 10 is a schematic block diagram illustrating a structure of a key distribution apparatus of a wireless body area network according to an embodiment of the present application;

fig. 11 is a schematic block diagram illustrating a structure of a key distribution apparatus of a wireless body area network according to an embodiment of the present application;

fig. 12 is a schematic block diagram illustrating a structure of a key generation apparatus of a wireless body area network according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of a coordinator node according to an embodiment of the present application;

fig. 14 is a schematic structural diagram of a wearable device provided in an embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application.

A Wireless Body Area Network (WBAN) is a communication Network centered on a human Body and composed of various Network elements related to the human Body. These network elements may be sensors deployed at various parts of the body, and/or wearable devices worn at various parts of the human body. A wearable device refers to a portable device that may be worn directly on the body or integrated into a user's clothing or accessory. For example, a smart watch, smart glasses, smart bracelet, or other wearable vital signs monitoring device.

Referring to fig. 1, fig. 1 is a schematic block diagram of a system architecture of a wireless body area network according to an embodiment of the present disclosure. The wireless body area network comprises a coordinator node 11 and at least one wearable device 12 in communication connection with the coordinator node, wherein acceleration acquisition devices are integrated on the coordinator node 11 and the wearable device 12. The acceleration acquisition device can be, but is not limited to, a three-axis acceleration sensor, and the coordinator node and the wearable device can acquire gait acceleration signals of the user through the acceleration acquisition device.

The coordinator node is used for sending a data acquisition synchronization message to the wearable device; acquiring a first step state acceleration signal; extracting first gait common information in the first step state acceleration signal; generating key encryption information according to the key to be distributed and the first gait common information; and sending the key encryption information to the wearable device. The first gait common information is position information of a peak value and a valley value of the first gait acceleration signal.

The wearable device is used for receiving the data acquisition synchronization message and synchronously acquiring a second-step acceleration signal according to the data acquisition synchronization message; extracting second gait common information in the second step state acceleration signal; receiving key encryption information; and decrypting the key encryption information according to the second gait common information to obtain the key to be distributed. The second gait common information is the position information of the peak value and the valley value of the second step state acceleration signal.

It should be noted that the above coordinator node may also be referred to as a wearable gateway, and the coordinator node may function as a gateway in the wireless body area network. The coordinator node is in wireless communication connection with at least one wearable device, and the wireless communication mode can be any mode.

In the key distribution process, the coordinator node sends broadcast data acquisition synchronization messages to each wearable device, and after the wearable device receives the data acquisition synchronization messages, the wearable device completes the synchronous acquisition of gait acceleration signals according to the data acquisition synchronization messages. The synchronous acquisition of the gait acceleration signals means that the coordinator node and the wearable equipment acquire gait acceleration information at the same moment through the acceleration acquisition devices of the coordinator node and the wearable equipment. Namely, the first step acceleration signal and the second step acceleration signal are synchronously acquired and are gait acceleration information at the same moment, and the first step acceleration signal and the second step acceleration signal are merely gait acceleration signals acquired by which equipment is distinguished.

After the coordinator node and the wearable device synchronously acquire the gait acceleration signals, a corresponding key distribution process can be performed.

After the coordinator node collects the first-step acceleration signal, gait common information extraction can be carried out according to the first-step acceleration signal, then the key to be distributed is encrypted according to the extracted first gait common information, and the encrypted key encryption information obtained through encryption is sent to each wearable device.

After the wearable device collects the second-step acceleration signals, extracting second gait common information in the second-step acceleration signals; and after the wearable device receives the key encryption information sent by the coordinator node, decrypting the key encryption information by using the second gait common information to obtain the key to be distributed. Therefore, the key to be distributed generated by the coordinator node can be shared to each wearable device of the wireless body area network, and the key distribution of the wireless body area network is realized. After key distribution, data encryption transmission between the coordinator node and each wearable device can be performed using the key.

The gait common information is position information of a peak and a bottom of the gait acceleration signal. Specifically, on a gait acceleration signal curve, the position information is obtained by correspondingly encoding according to the position of the peak value and the time sequence position of the valley value. For example, when gait common information is extracted through a sliding window, the sliding window is used for sliding on a gait acceleration signal curve, when a peak value appears in the 1 st sliding window, the sliding window is coded as 1, when a valley value appears in the 2 th sliding window, the sliding window is coded as-1, correspondingly, when the peak value and the valley value do not appear in the 3 rd sliding window, the sliding window is not coded, and therefore the position information of the peak value and the valley value on the gait acceleration signal curve is extracted.

In some embodiments, the coordinator node is specifically configured to: carrying out low-pass filtering on the first step state acceleration signal; performing dimensionality reduction operation on the first step acceleration signal subjected to low-pass filtering to obtain a dimensionality reduced first step acceleration signal; and respectively extracting first position information of a peak value and a valley value of the first-step acceleration signal after the dimensionality reduction of the time domain and the dimensionality reduction of the frequency domain.

The filtering operation performed on the first-step acceleration signal may be, but is not limited to, butterworth low-pass filtering. The dimension reduction operation may be, but is not limited to, Principal Component Analysis (PCA), and subsequent analysis is performed based on the dimension-reduced first-step acceleration signal.

For example,

pca_signal＝E(:,1)*r_signal

wherein r _ signal is the first step acceleration signal, x, y, z respectively represent x axis, y axis and z axis of triaxial acceleration, and PCA _ signal is the first principal component after dimensionality reduction by PCA. Of course, the dimension reduction algorithm may be other algorithms, and is not limited herein.

After the dimensionality reduction is performed on the first step acceleration signal, the position information of the peak value and the valley value of the first step acceleration signal in the time domain and the position information of the peak value and the valley value of the first step acceleration signal in the frequency domain can be extracted. The position information may be extracted in any manner. In some embodiments, a signed sliding code algorithm may be used for extraction.

Further, the coordinator node is specifically configured to: extracting first position information of peak values and valley values of the first-step acceleration signals after dimension reduction and the fast Fourier transform results of the first-step acceleration signals after dimension reduction based on a signed sliding window coding algorithm;

the process of the Signed sliding window coding algorithm (SSWC) specifically includes:

the signed sliding window slides on the first step state acceleration signal after dimensionality reduction, and when the ith window has a peak value, i is added to the common information pool; when the ith window has a valley value, increasing-i in the common information pool; when the ith window does not have a peak and/or a valley, the window continues to slide, i being an integer. For example, when the 1 st window has a peak, the common information pool is increased by 1, and when the 5 th window has a valley, the common information pool is increased by-5.

Or, the signed sliding window slides on the first step state acceleration signal after the dimensionality reduction, and when the ith window has a peak value, the common information pool is increased by-i; when the ith window has a valley value, increasing i in the common information pool; when the ith window does not have a peak and/or a valley, the window continues to slide, i being an integer. For example, when the 1 st window has a peak, the common information pool is increased by-1, and when the 5 th window has a valley, the common information pool is increased by 5.

Specifically, the signed sliding window coding algorithm is used for extracting the position information of the peak value and the valley value of the first-step acceleration signal after dimension reduction and the position information of the peak value and the valley value of the fast fourier transform result of the first-step acceleration signal after dimension reduction respectively to obtain the first position information.

The window coding of the frequency domain is continued to the coding of the time domain window, and in the specific application, the sizes of the sliding windows of the time domain and the frequency domain are respectively W_tAnd W_f，W_tAnd W_fThe value of (c) is determined by the sampling frequency of the gait acceleration signal. See FIG. 2 for a signed window code diagram, W_tSet to 20 sample points, W_fSetting 1Hz, correspondingly coding the gait acceleration signals in the time domain to be +/-1, +/-2, +/-3, …, +/-24 and +/-25 according to the positions of peak values and valley values, coding the gait acceleration signal curve in the frequency domain after the coding of the gait acceleration signals in the time domain is finished, continuously coding the gait acceleration signal curve to be +/-26, +/-27, +/-28, …, +/-40 and +/-41, and obtaining the gait acceleration signals in the time domain and the frequency domain after the coding of the gait acceleration signals in the time domain and the frequency domain is finishedCorresponding encoded information.

Therefore, the method can further improve the extraction convenience of the gait common information and reduce the calculation amount by the symbolic sliding window algorithm. Further, the encoding rate can be improved by expressing the peak and the valley by different sign numbers.

The gait common information extraction process of the wearable device is similar to the gait common information extraction process of the coordinator node. In some embodiments, the wearable device described above is specifically for: low-pass filtering the second-step acceleration signal; performing dimensionality reduction operation on the low-pass filtered second-step state acceleration signal to obtain a dimensionality-reduced second-step state acceleration signal; and respectively extracting second position information of the peak value and the valley value of the second step state acceleration signal after the time domain and the frequency domain dimensionality reduction.

The dimension reduction operation may be, but is not limited to, a PCA dimension reduction algorithm. After the dimension reduction, the position information of the peak and the valley of the second step state acceleration signal in the time domain and the position information of the peak and the valley of the second step state acceleration signal in the frequency domain may be extracted respectively. The position information may be extracted by a signed sliding window coding algorithm.

Further, the wearable device is specifically configured to:

extracting second position information of peak values and valley values of the second-step state acceleration signals after dimension reduction and the fast Fourier transform results of the second-step state acceleration signals after dimension reduction based on a signed sliding window coding algorithm;

the process of the signed sliding window coding algorithm specifically comprises the following steps:

the signed sliding window slides on the second-step state acceleration signal after dimensionality reduction, and when the ith window has a peak value, i is added to the common information pool; when the ith window has a valley value, increasing-i in the common information pool; when the ith window does not have a peak and/or a valley, the window continues to slide, i being an integer.

Or, the signed sliding window slides on the first step state acceleration signal after the dimensionality reduction, and when the ith window has a peak value, the common information pool is increased by-i; when the ith window has a valley value, increasing i in the common information pool; when the ith window does not have a peak and/or a valley, the window continues to slide, i being an integer.

It should be noted that the signed sliding window coding algorithm in the wearable device is the same as the signed sliding window coding algorithm in the coordinator node, and for related introduction, reference is made to the above corresponding contents, which are not described herein again.

It is worth pointing out that the symbolic sliding window coding algorithm can enable the gait common information extraction process to be simpler and more convenient, the calculation amount is less, and the algorithm is suitable for wearable equipment with limited calculation resources.

After the coordinator node extracts the first gait common information from the first step acceleration signal, the coordinator node may encrypt the key to be distributed by using the first gait common information to obtain encrypted key encryption information. In specific application, the key to be distributed is encrypted by using the first gait common information based on a Fuzzy safe algorithm (Fuzzy Vault), so that a Fuzzy safe is constructed.

In some embodiments, the coordinator node is specifically configured to: dividing a key to be distributed into N sections, wherein each section of the key to be distributed is a coefficient of an N-order polynomial; and constructing a fuzzy safe box according to the first gait common information and the N-order polynomial, wherein the fuzzy safe box is secret key encryption information.

Specifically, the M-bit key to be distributed is key _ M, and the M-bit key to be distributed is divided into N segments, that is, key _ M ═ C₀//C₁//C₂//...//C_NEach segment is a coefficient of an nth order polynomial, specifically f (x) C₀+C₁x+C₂x²+...+C_Nx^N。

The first gait common information extracted by the coordinator node is (g)₁,g₂,...,g_k) If k is larger than N, the first gait common information is substituted into the above f (x), and the set p { (g) is obtained₁,f(g₁),(g₂,f(g₂),...,(g_k,f(g_k) And adding a miscellaneous point set C into the set P to form a Vault set V in public. After the building is completed, the coordinator node sends the vault set V to the wearable device。

Of course, the way of obtaining the key encryption information according to the first gait common information and the key to be distributed may not be limited to Fuzzy Vault.

After the wearable device extracts the second-step common information, the wearable device may wait for receiving the key encryption information sent by the coordinator node. After the wearable device receives the key encryption information, the key encryption information can be decrypted by using the second gait common information to obtain a key to be distributed.

In a specific application, when the key encryption information is a fuzzy safe, the wearable device is specifically configured to: and unlocking the fuzzy safe box according to the second gait common information to obtain the key to be distributed.

After the wearable device receives the vault set V, a set P is found from the set V according to second gait common information, and the polynomial f (x) is solved according to the set P to obtain a polynomial coefficient C₀,C₁,C₂,...,C_NAnd then, splicing the polynomial coefficients to obtain the M-bit key to be distributed.

In this way, the coordinator node shares the key to be distributed to each wearable device in the wireless body area network through the gait common information in the gait acceleration signal.

It should be noted that the above-mentioned generation manner of the key to be distributed may be arbitrary. For example, the gait acceleration signal may be used to generate a key to be assigned. In order to improve the randomness and the information entropy of the key to be distributed, the key to be distributed can be generated through a noise signal superposed on the gait acceleration signal. In some embodiments, the coordinator node is specifically configured to: and generating a key to be distributed according to the noise signal in the first step state acceleration signal.

After the coordinator node acquires the first-step acceleration signal, a noise signal in the first-step acceleration signal may be extracted, and the key to be distributed is generated according to the noise signal. That is, the coordinator node may be specifically configured to: extracting a noise signal in the first step state acceleration signal; coding the noise signal to obtain a secret key; and carrying out key enhancement operation on the key to obtain the key to be distributed.

Generating the key to be distributed according to the noise signal superimposed on the gait acceleration signal may include steps of noise extraction, noise encoding, key enhancement, and the like.

For the noise extraction step, the first step acceleration signal may be filtered, and then the first step acceleration signal after filtering and the first step acceleration signal before filtering are subtracted from each other to obtain a noise information sum. That is, the coordinator node is specifically configured to: carrying out zero phase filtering on the first step state acceleration signal to obtain a filtered first step state acceleration signal; and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain a noise signal.

More specifically, the process of the zero-phase filtering specifically includes: inputting the first step acceleration signal into a low-pass Butterworth filter to obtain a first step acceleration signal which is output by the low-pass Butterworth filter and is subjected to first filtering; carrying out time reversal operation on the first filtered step state acceleration signal to obtain a first reversed step state acceleration signal; inputting the first step acceleration signal after the first inversion into a low-pass Butterworth filter to obtain a second filtered first step acceleration signal output by the low-pass Butterworth filter; and performing time reversal operation on the first step acceleration signal subjected to the second filtering to obtain a first step acceleration signal subjected to the second reversal, wherein the first step acceleration signal subjected to the second reversal is the first step acceleration signal subjected to the filtering.

In order to better describe the zero-phase filtering process provided by the embodiment of the present application, the following description will be made with reference to a schematic zero-phase filtering flow diagram shown in fig. 3.

As shown in fig. 3, the original first step acceleration signal r _ sig is x₁,x₂,x₃,...,x_N-1,x_NInputting the signals into a low-pass Butterworth filter to obtain a first-stage acceleration signal f _ sig ═ x 'after first filtering'₁,x'₂,x'₃,...,x'_N-1,x'_N(ii) a Then theTime reversal operation is carried out on f _ sig to obtain a first step acceleration signal rev _ f _ sig ═ x 'after first reversal'_N,x'_N-1,x'_N-2,...,x'₂,x'₁(ii) a Inputting rev _ f _ sig into a low-pass Butterworth filter, and carrying out second filtering to obtain a first step state acceleration signal ff _ sig ═ x'_N,x”_N-1,x”_N-2,...,x”₂,x”₁(ii) a Finally, the ff _ sig is subjected to second time inversion to obtain a second-time inverted first-step acceleration signal rev _ ff _ sig ═ x'₁,x”₂,x”₃,...,x”_N-1,x”_N. rev _ ff _ sig is the first step acceleration signal after zero-phase filtering.

And then, subtracting the first step acceleration signal after zero phase filtering from the original first step acceleration signal to obtain a noise signal. That is, n _ sig is r _ sig-rev _ ff _ sig, and n _ sig is a noise signal in the first step acceleration signal.

After the noise signal in the first-step acceleration signal is extracted, the noise signal may be encoded. Generally, an acceleration acquisition device on a coordinator node is a three-axis acceleration sensor, acceleration signals of an x axis, a y axis and a z axis acquired by the three-axis acceleration sensor are acquired, at this time, noise signals include a first noise signal of the x axis, a second noise signal of the y axis and a third noise signal of the z axis, and the coordinator node is specifically configured to: setting corresponding bits of the first binary random sequence as corresponding values according to the values of the bits in the first noise signal to obtain a first secret key; setting corresponding bits of the second binary random sequence as corresponding values according to the values of the bits in the second noise signal to obtain a second key; setting corresponding bits of the third binary random sequence as corresponding numerical values according to numerical values of the bits in the third noise signal to obtain a third key;

if the kth bit in the noise signal is greater than or equal to 0, setting the kth bit of the binary random sequence as a first numerical value; and if the k-th bit in the noise signal is less than 0, setting the k-th bit of the binary random sequence as a second numerical value, wherein k is an integer.

Specifically, the first value may be 1, and correspondingly, the second value may be 0. Of course, the first value may be 0, and the second value may be 1.

For example, if the 1 st bit in the first noise signal is greater than or equal to 0, the 1 st bit of the first binary random sequence is set to 1, and the 2 nd bit in the first noise signal is less than 0, the 2 nd bit of the first binary random sequence is set to 0, and so on, and according to the magnitude of each bit in the first noise signal, the corresponding bit of the first binary random sequence is set to a corresponding value.

Referring to fig. 4, a schematic diagram of coding based on noise signals is shown, which includes three images, i.e., a gait acceleration signal curve corresponding to an x-axis, a y-axis and a z-axis from top to bottom and a gait acceleration signal curve after zero-phase filtering. According to the original gait acceleration signal and the filtered gait acceleration signal, binary random sequences key _ x, key _ y and key _ z are obtained, wherein the key _ x is 0000011100 … 110000, the key _ y is 0111111001 … 011111, and the key _ z is 0000110001 … 111000.

After the noise signal is encoded, the obtained key is subjected to key enhancement operation. In some embodiments, the key enhancement process may specifically include: and carrying out exclusive OR operation on the first key, the second key and the third key to obtain M keys to be distributed. That is, key _ M ≧ key _ x ≦ key _ y ≦ key _ z.

In other embodiments, the key enhancement process further comprises: performing exclusive-or operation on the first key, the second key and the third key to obtain an exclusive-or key; and performing downsampling on the XOR key to obtain a key to be distributed.

It is worth pointing out that performing an exclusive-or operation on the keys can further improve the randomness and the information entropy of the generated keys to be distributed. Further, after the exclusive-or operation, a downsampling operation is also performed, so that the randomness and the information entropy of the key to be distributed can be further improved.

After the introduction of the coordinator node and the wearable device of the wireless body area network, the workflow on the coordinator node side and the workflow on the wearable device side will be described below, respectively.

The workflow on the coordinator node side is first introduced. Referring to fig. 5, a schematic block diagram of a flow of a key distribution method for a wireless body area network according to an embodiment of the present application is provided, where the method may employ a coordinator node of the wireless body area network, the coordinator node being integrated with an acceleration acquisition device, and the coordinator node being in communication connection with at least one wearable device. The above method may comprise the steps of:

step S501, sending a data acquisition synchronization message to the wearable device, wherein the data acquisition synchronization message is used for indicating the wearable device to synchronously acquire second-step acceleration signals.

Specifically, the coordinator node broadcasts the data acquisition synchronization message, so that each wearable device in the wireless body area network acquires synchronization information according to the data, and when the coordinator node acquires a first-step acceleration signal, a second-step acceleration signal is acquired synchronously through each acceleration sensor.

And step S502, acquiring a first-step acceleration signal.

And S503, extracting first gait common information in the first step acceleration signal.

The extraction process of the first gait common information specifically comprises the following steps: carrying out low-pass filtering on the first step state acceleration signal; performing dimensionality reduction operation on the first step acceleration signal subjected to low-pass filtering to obtain a dimensionality reduced first step acceleration signal; and respectively extracting first position information of a peak value and a valley value of the first-step acceleration signal after the dimensionality reduction of the time domain and the dimensionality reduction of the frequency domain.

More specifically, the process of extracting the first position information of the peak and the valley of the first-step acceleration signal after the dimensionality reduction of the time domain and the frequency domain respectively may include:

extracting first position information of peak values and valley values of the first-step acceleration signals after dimension reduction and the fast Fourier transform results of the first-step acceleration signals after dimension reduction based on a signed sliding window coding algorithm;

the signed sliding window slides on the first step state acceleration signal after dimensionality reduction, and when the ith window has a peak value, i is added to the common information pool; when the ith window has a valley value, increasing-i in the common information pool; when the ith window does not have a peak and/or a valley, the window continues to slide, i being an integer.

It should be noted that for the related introduction of the extraction process of the first gait common information, please refer to the above corresponding contents, which are not described herein again.

And step S504, generating key encryption information according to the key to be distributed and the first gait common information.

The generation method of the key encryption information may be, but is not limited to, Fuzzy Vault. In some embodiments, when the key encryption information is a fuzzy safe, the specific process includes: dividing a key to be distributed into N sections, wherein each section of the key to be distributed is a coefficient of an N-order polynomial; and constructing a fuzzy safe box according to the first gait common information and the N-order polynomial, wherein the fuzzy safe box is secret key encryption information. For related introduction, please refer to the corresponding content above, which is not described herein again.

Step S505, sending the key encryption information to the wearable device to indicate the wearable device to decrypt the key encryption information according to second gait common information extracted from the second step acceleration signal to obtain a key to be distributed; the first gait common information is position information of a peak value and a valley value of the first step acceleration signal; the second gait common information is the position information of the peak value and the valley value of the second step state acceleration signal.

Specifically, after the coordinator node sends the key encryption information to each wearable device in the wireless body area network, the wearable device may perform an interface according to the second gait common information extracted by the wearable device, so as to obtain the key to be distributed.

It is worth pointing out that the generation manner of the key to be distributed may be arbitrary. However, in order to improve the randomness and the information entropy of the key, the key may be generated based on a noise signal superimposed on the gait acceleration signal.

Referring to fig. 6, a schematic block diagram of a process for generating a key to be distributed according to a noise signal, where a process for generating a key to be distributed according to a noise signal superimposed on a first-step acceleration signal specifically includes:

and step S601, extracting a noise signal in the first-step acceleration signal.

Specifically, the process of extracting the noise signal specifically includes: carrying out zero-phase filtering on the first-step acceleration signal; and subtracting the filtered first-step acceleration signal from the first-step acceleration signal to obtain a noise signal superposed on the first-step acceleration signal. The zero-phase filtering process may refer to the related description corresponding to fig. 3 above, and is not described herein again.

Step S602, encode the noise signal to obtain a key.

It should be noted that, the noise encoding process may refer to the corresponding content above, and is not described herein again.

And step S603, performing key enhancement operation on the key to obtain the key to be distributed.

Specifically, the first key, the second key, and the third key may be subjected to an exclusive or operation to obtain a key to be distributed. Or performing exclusive or operation on the first key, the second key and the third key to obtain an exclusive or key; and then, downsampling the key subjected to the XOR to obtain the key to be distributed.

In some embodiments, the generation process of the key to be distributed specifically includes: and generating a key to be distributed according to the noise signal in the first step state acceleration signal.

Further, the process of generating the key to be distributed according to the noise signal in the first step acceleration signal may specifically include: extracting a noise signal in the first step state acceleration signal; coding the noise signal to obtain a secret key; and carrying out key enhancement operation on the key to obtain the key to be distributed.

Specifically, the above process of extracting the noise signal in the first-step acceleration signal may include: carrying out zero phase filtering on the first step state acceleration signal to obtain a filtered first step state acceleration signal; and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain a noise signal.

The zero-phase filtering process specifically includes: inputting the first step acceleration signal into a low-pass Butterworth filter to obtain a first step acceleration signal which is output by the low-pass Butterworth filter and is subjected to first filtering;

carrying out time reversal operation on the first filtered step state acceleration signal to obtain a first reversed step state acceleration signal;

inputting the first step acceleration signal after the first inversion into a low-pass Butterworth filter to obtain a second filtered first step acceleration signal output by the low-pass Butterworth filter;

and performing time reversal operation on the first step acceleration signal subjected to the second filtering to obtain a first step acceleration signal subjected to the second reversal, wherein the first step acceleration signal subjected to the second reversal is the first step acceleration signal subjected to the filtering.

In some embodiments, the acceleration acquisition device is a three-axis acceleration sensor, and the noise signal includes a first noise signal of an x-axis, a second noise signal of a y-axis, and a third noise signal of a z-axis;

the specific process of encoding the noise signal to obtain the key may include:

setting corresponding bits of the first binary random sequence as corresponding values according to the values of the bits in the first noise signal to obtain a first secret key;

setting corresponding bits of the second binary random sequence as corresponding values according to the values of the bits in the second noise signal to obtain a second key;

setting corresponding bits of the third binary random sequence as corresponding numerical values according to numerical values of the bits in the third noise signal to obtain a third key;

Further, the above-mentioned performing a key enhancement operation on the key to obtain the key to be distributed may include:

performing exclusive-or operation on the first key, the second key and the third key to obtain a key to be distributed;

or,

performing exclusive-or operation on the first key, the second key and the third key to obtain an exclusive-or key;

and performing downsampling on the XOR key to obtain a key to be distributed.

In some embodiments, the extracting the first gait common information in the first step acceleration signal may include:

carrying out low-pass filtering on the first step state acceleration signal;

performing dimensionality reduction operation on the first step acceleration signal subjected to low-pass filtering to obtain a dimensionality reduced first step acceleration signal;

and respectively extracting first position information of a peak value and a valley value of the first-step acceleration signal after the dimensionality reduction of the time domain and the dimensionality reduction of the frequency domain.

In some embodiments, the extracting the first position information of the peak and the valley of the first step acceleration signal after the time domain and the frequency domain dimensionality reduction respectively specifically includes:

In some embodiments, the generating of the key encryption information according to the key to be distributed and the first gait common information specifically includes:

dividing a key to be distributed into N sections, wherein each section of the key to be distributed is a coefficient of an N-order polynomial;

and constructing a fuzzy safe box according to the first gait common information and the N-order polynomial, wherein the fuzzy safe box is secret key encryption information.

It should be noted that please refer to other embodiments for the related introduction of the work flow of the coordinator node, which is not described herein again.

After the workflow on the coordinator node side is introduced, the workflow on the wearable device side is introduced next.

Referring to fig. 7, a schematic block diagram of a flow of a key distribution method for a wireless body area network provided in an embodiment of the present application is shown, where the method may be applied to a wearable device of the wireless body area network, the wearable device is integrated with an acceleration acquisition apparatus, and the wearable device is in communication connection with a coordinator node. The above method may comprise the steps of:

and step S701, receiving a data acquisition synchronization message sent by the coordinator node.

And step S702, synchronously acquiring a second-step acceleration signal according to the data acquisition synchronous message.

And step S703, extracting second gait common information in the second step state acceleration signal.

It should be noted that the process of extracting the second gait common information is similar to the process of extracting the first gait common information, and in addition, reference may be made to the above related content regarding the process of extracting the gait common information. And will not be described in detail herein.

Step S704, receiving key encryption information sent by the coordinator node, where the key encryption information is information generated by the coordinator node according to the first gait common information extracted from the collected first step acceleration signal and the key to be distributed.

Step S705, decrypting the key encryption information according to the second gait common information to obtain a key to be distributed; the first gait common information is position information of a peak value and a valley value of the first step acceleration signal; the second gait common information is the position information of the peak value and the valley value of the second step state acceleration signal.

In some embodiments, the extracting second gait common information in the second step acceleration signal may include:

low-pass filtering the second-step acceleration signal;

performing dimensionality reduction operation on the low-pass filtered second-step state acceleration signal to obtain a dimensionality-reduced second-step state acceleration signal;

and respectively extracting second position information of the peak value and the valley value of the second step state acceleration signal after the time domain and the frequency domain dimensionality reduction.

Further, the above process of extracting the second position information of the peak and the valley of the second step acceleration signal after the time domain and the frequency domain dimensionality reduction respectively may include:

In some embodiments, the key encryption information is a fuzzy safe, and the specific process of decrypting the key encryption information according to the second gait common information to obtain the key to be distributed may include:

and unlocking the fuzzy safe box according to the second gait common information to obtain the key to be distributed.

It should be noted that please refer to other embodiments for related descriptions of the workflow of the wearable device, which are not described herein.

After the workflow of the coordinator node side and the wearable device side is described, the key generation process of the coordinator node once will be described below.

Referring to fig. 8, a schematic flow diagram of a key generation method for a wireless body area network is shown, where the key generation method is applied to a coordinator node of the wireless body area network, and the coordinator node is integrated with an acceleration acquisition device, where the method may include the following steps:

and step S801, acquiring a first-step acceleration signal.

And step S802, extracting a noise signal in the first-step acceleration signal.

Step S803, a key to be distributed is generated from the noise signal.

Specifically, after the first-step acceleration signal is acquired, zero-phase filtering may be performed on the first-step acceleration signal, and then the first-step acceleration signal after filtering is subtracted from the first-step acceleration signal, so as to extract the noise signal. Then, the noise signal is encoded, and then the key enhancement operation is performed after the encoding, so as to generate the key to be distributed.

The key to be distributed is generated through the noise signal superposed on the first gait acceleration signal, and the randomness and the information entropy of the key can be improved.

In some embodiments, the above process of extracting the noise signal in the first step acceleration signal may include:

carrying out zero phase filtering on the first step state acceleration signal to obtain a filtered first step state acceleration signal;

and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain a noise signal. Further, the process of performing zero-phase filtering on the first step acceleration signal to obtain a filtered first step acceleration signal may include:

inputting the first step acceleration signal into a low-pass Butterworth filter to obtain a first step acceleration signal which is output by the low-pass Butterworth filter and is subjected to first filtering;

In some embodiments, the generating the key to be distributed according to the noise signal may include:

coding the noise signal to obtain a secret key;

and carrying out key enhancement operation on the key to obtain the key to be distributed.

the process of encoding the noise signal to obtain the key may include:

In some embodiments, the performing a key enhancement operation on the key to obtain the key to be distributed may include:

or,

and performing downsampling on the XOR key to obtain a key to be distributed.

It should be noted that, for the process of generating the key to be distributed according to the noise signal superimposed on the first step acceleration signal, the specific description may refer to the above corresponding contents, and is not described herein again.

It should be understood that the technical solution of generating a key through a noise signal, which is provided by the embodiments of the present application, is also used alone and falls into the scope of the embodiments of the present application.

The interaction process between the coordinator node and the wearable device will be described below with reference to the schematic interaction diagram shown in fig. 9. The interaction process may include:

step S901, the coordinator node sends a data acquisition synchronization message to the wearable device.

And S902, the coordinator node acquires a first step state acceleration signal.

And step S903, the wearable device synchronously acquires the second-step acceleration signal according to the data acquisition synchronous message.

And step S904, extracting the noise signal in the first-step acceleration signal by the coordinator node.

And step S905, after the coordinator node encodes the noise signal, performing key enhancement operation to generate a key to be distributed.

In other embodiments, the key to be distributed may also be generated by the first gait acceleration signal or in other manners. But the random property and the information entropy of the key can be improved by generating the key to be distributed through the noise signal in the gait acceleration signal.

And step S906, the coordinator node extracts first gait common information in the first step state acceleration signal.

The first gait common information is position information of a peak value and a valley value of the first gait acceleration signal. The process of extracting the gait common information can refer to the above corresponding contents, and is not described in detail herein.

And S907, the coordinator node constructs a fuzzy safe according to the gait common information and the key to be distributed.

It will be appreciated that in other embodiments, other ways of encrypting the keys to be distributed may be used.

Step S908, the coordinator node sends the fuzzy safe to the wearable device.

Step S909, the wearable device extracts the second gait common information in the second step acceleration signal.

The second gait common information is position information of a peak value and a valley value of the second step state acceleration signal. The process of extracting the gait common information can refer to the above corresponding contents, and is not described in detail herein.

Step S910, after the wearable device receives the fuzzy safe, unlocking the fuzzy safe according to the second gait common information to obtain the key to be distributed.

It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The corresponding apparatus of the above method will be described below. Please refer to fig. 10, which is a schematic block diagram illustrating a structure of a key distribution device of a wireless body area network according to an embodiment of the present disclosure, in which a coordinator node of the wireless body area network is applied, the coordinator node is integrated with an acceleration acquisition device, and the coordinator node is in communication connection with at least one wearable device; the apparatus may include:

the synchronous message sending module 101 is configured to send a data acquisition synchronous message to the wearable device, where the data acquisition synchronous message is used to instruct the wearable device to synchronously acquire a second-step acceleration signal;

the first acquisition module 102 is used for acquiring a first step acceleration signal;

the first extraction module 103 is configured to extract first gait common information in the first step acceleration signal;

the encrypted information generating module 104 is configured to generate key encrypted information according to the key to be distributed and the first gait common information;

the encrypted information sending module 105 is configured to send the key encrypted information to the wearable device to instruct the wearable device to decrypt the key encrypted information according to the second gait common information extracted from the second step acceleration signal, so as to obtain a key to be distributed;

the first gait common information is position information of a peak value and a valley value of the first step acceleration signal; the second gait common information is the position information of the peak value and the valley value of the second step state acceleration signal.

The key assignment device of the wireless body area network may be a software program in the coordinator node, and each module of the key assignment device of the wireless body area network may be a corresponding software program module.

In some embodiments, the apparatus further includes a key generation module, configured to generate a key to be distributed according to a noise signal in the first step acceleration signal.

Further, the key generation module is specifically configured to: extracting a noise signal in the first step state acceleration signal; coding the noise signal to obtain a secret key; and carrying out key enhancement operation on the key to obtain the key to be distributed.

Further, the key generation module is specifically configured to: carrying out zero phase filtering on the first step state acceleration signal to obtain a filtered first step state acceleration signal; and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain a noise signal.

Further, the key generation module is specifically configured to: inputting the first step acceleration signal into a low-pass Butterworth filter to obtain a first step acceleration signal which is output by the low-pass Butterworth filter and is subjected to first filtering;

the key generation module is specifically configured to:

Further, the key generation module is specifically configured to:

or,

and performing downsampling on the XOR key to obtain a key to be distributed.

In some embodiments, the first extraction module is specifically configured to:

carrying out low-pass filtering on the first step state acceleration signal;

In some embodiments, the first extraction module is specifically configured to:

In some embodiments, the encryption information generating module is specifically configured to:

Referring to fig. 11, a schematic block diagram of a structure of a key distribution device of a wireless body area network provided in an embodiment of the present application is applied to a wearable device of the wireless body area network, the wearable device is integrated with an acceleration acquisition device, and the wearable device is in communication connection with a coordinator node; the apparatus may include:

a first receiving module 111, configured to receive a data acquisition synchronization message sent by a coordinator node;

the synchronous acquisition module 112 is used for acquiring the second-step acceleration signals synchronously according to the data acquisition synchronous messages;

the second extraction module 113 is configured to extract second gait common information in the second step acceleration signal;

a second receiving module 114, configured to receive key encryption information sent by the coordinator node, where the key encryption information is information generated by the coordinator node according to the first gait common information extracted from the acquired first step acceleration signal and the key to be distributed;

the decryption module 115 is configured to decrypt the key encryption information according to the second gait common information to obtain a key to be distributed;

The key distribution device of the wireless body area network may be a software program in the wearable device, and each module of the key distribution device of the wireless body area network may be a corresponding software program module.

In some embodiments, the second extraction module is specifically configured to:

low-pass filtering the second-step acceleration signal;

Further, the second extraction module is specifically configured to:

In some embodiments, the key encryption information is a fuzzy safe, and the decryption module is specifically configured to:

Referring to fig. 12, a schematic block diagram of a structure of a key generation apparatus for a wireless body area network provided in an embodiment of the present application is a block diagram, where the apparatus is applied to a coordinator node of the wireless body area network, the coordinator node is integrated with an acceleration acquisition apparatus, and the apparatus may include:

and the second acquisition module 121 is configured to acquire the first step acceleration signal.

And the noise extraction module 122 is configured to extract a noise signal in the first-step acceleration signal.

And a key generating module 123, configured to generate a key to be distributed according to the noise signal.

It should be noted that the apparatuses shown in fig. 10, fig. 11, and fig. 12 correspond to the above methods one to one, and for related descriptions, reference is made to the above corresponding contents, which is not described herein again.

It should be noted that, for the information interaction, the execution process, and other contents between the above-mentioned apparatuses, the specific functions and the technical effects of the embodiments of the method of the present application are based on the same concept, and specific reference may be made to the section of the embodiments of the method, which is not described herein again.

The key generation device of the wireless body area network may be a software program in the coordinator node, and each module of the key generation device of the wireless body area network may be a corresponding software program module.

In some embodiments, the noise extraction module is specifically configured to:

and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain a noise signal.

Further, the noise extraction module is specifically configured to:

In some embodiments, the key generation module is specifically configured to:

coding the noise signal to obtain a secret key;

the key generation module is specifically configured to:

In some embodiments, the key generation module is specifically configured to:

or,

and performing downsampling on the XOR key to obtain a key to be distributed.

Fig. 13 is a schematic structural diagram of a coordinator node according to an embodiment of the present application. As shown in fig. 13, the coordinator node 13 of this embodiment includes: at least one processor 130, a memory 131 and a computer program 132 stored in the memory 131 and executable on the at least one processor 130, the processor 130 implementing the steps in any of the above-mentioned embodiments of the key distribution method for a wireless body area network or the key generation method for a wireless body area network when executing the computer program 132.

The coordinator node 13 may be a wearable gateway. The coordinator node may include, but is not limited to, a processor 130, a memory 131, and an acceleration acquisition device 133. Those skilled in the art will appreciate that fig. 13 is merely an example of the coordinator node 13, and does not constitute a limitation of the coordinator node 13, and may include more or less components than those shown, or combine some components, or different components, such as input and output devices, network access devices, etc.

The Processor 130 may be a Central Processing Unit (CPU), and the Processor 130 may be other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The storage 131 may in some embodiments be an internal storage unit of the coordinator node 13, such as a hard disk or a memory of the coordinator node 13. The memory 131 may also be an external storage device of the coordinator node 13 in other embodiments, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like, which are provided on the coordinator node 13. Further, the memory 131 may also include both an internal storage unit and an external storage device of the coordinator node 13. The memory 131 is used for storing an operating system, an application program, a BootLoader (BootLoader), data, and other programs, such as program codes of the computer programs. The memory 131 may also be used to temporarily store data that has been output or is to be output.

Fig. 14 is a schematic structural diagram of a wearable device according to an embodiment of the present application. As shown in fig. 14, the wearable device 14 of this embodiment includes: at least one processor 140, a memory 141, and a computer program 142 stored in the memory 141 and executable on the at least one processor 140, the processor 140 implementing the steps in any of the various wireless body area network key distribution method embodiments described above when executing the computer program 142.

The wearable device 14 may be a wearable watch, a smart band, smart glasses, and the like. The wearable device may include, but is not limited to, a processor 140, a memory 141, and an acceleration acquisition device 143. Those skilled in the art will appreciate that fig. 14 is merely an example of a wearable device 14, and does not constitute a limitation of wearable device 14, and may include more or fewer components than shown, or some components in combination, or different components, such as input-output devices, network access devices, etc.

The Processor 140 may be a Central Processing Unit (CPU), and the Processor 140 may be other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 141 may be an internal storage unit of the wearable device 14 in some embodiments, such as a hard disk or a memory of the wearable device 14. The memory 141 may also be an external storage device of the wearable device 14 in other embodiments, such as a plug-in hard disk provided on the wearable device 14, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like. Further, the memory 141 may also include both an internal storage unit and an external storage device of the wearable device 14. The memory 141 is used for storing an operating system, an application program, a BootLoader (BootLoader), data, and other programs, such as program codes of the computer programs. The memory 141 may also be used to temporarily store data that has been output or is to be output.

An embodiment of the present application further provides a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the computer program implements the steps in the embodiments of the key distribution method for a wireless body area network or the embodiments of the key generation method for a wireless body area network.

When the computer program product runs on a coordinator node, the coordinator node implements the steps of the embodiments of the key distribution method for a wireless body area network or the embodiments of the key generation method for a wireless body area network when executing the embodiments. Alternatively, when the computer program product is run on a wearable device, the wearable device is enabled to implement the steps in the embodiments of the key distribution method for wireless body area networks described above when executed.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer-readable storage medium and can implement the steps of the embodiments of the methods described above when the computer program is executed by a processor. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include at least: any entity or device capable of carrying computer program code to a photographing apparatus/terminal apparatus, a recording medium, computer Memory, Read-Only Memory (ROM), Random Access Memory (RAM), an electrical carrier signal, a telecommunications signal, and a software distribution medium. Such as a usb-disk, a removable hard disk, a magnetic or optical disk, etc. In certain jurisdictions, computer-readable media may not be an electrical carrier signal or a telecommunications signal in accordance with legislative and patent practice.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus/network device and method may be implemented in other ways. For example, the above-described apparatus/network device embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implementing, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A wireless body area network, the wireless body area network includes coordinator node and with coordinator node communication connection's at least one wearable equipment, all integrated with acceleration acquisition device on coordinator node and the wearable equipment, its characterized in that:

2. The wireless body area network of claim 1, wherein the coordinator node is specifically configured to:

3. The wireless body area network of claim 2, wherein the coordinator node is specifically configured to:

extracting the noise signal in the first step-state acceleration signal; the acceleration acquisition device is a three-axis acceleration sensor, and the noise signals comprise a first noise signal of an x axis, a second noise signal of a y axis and a third noise signal of a z axis;

setting corresponding bits of a second binary random sequence as corresponding values according to the values of the bits in the second noise signal to obtain a second key;

setting corresponding bits of a third binary random sequence as corresponding values according to the values of the bits in the third noise signal to obtain a third key; if the kth bit in the noise signal is greater than or equal to 0, setting the kth bit of the binary random sequence as a first numerical value; if the kth bit in the noise signal is less than 0, setting the kth bit of the binary random sequence as a second numerical value, wherein k is an integer;

performing exclusive-or operation on the first key, the second key and the third key to obtain the key to be distributed; or, performing exclusive or operation on the first key, the second key and the third key to obtain an exclusive or key; and performing downsampling on the XOR key to obtain the key to be distributed.

4. The wireless body area network of claim 3, wherein the coordinator node is specifically configured to:

performing zero-phase filtering on the first step state acceleration signal to obtain a filtered first step state acceleration signal;

and subtracting the filtered first step acceleration signal from the first step acceleration signal to obtain the noise signal.

5. The wireless body area network of claim 4, wherein the coordinator node is specifically configured to:

inputting the first step state acceleration signal to a low-pass Butterworth filter to obtain a first step state acceleration signal which is output by the low-pass Butterworth filter and is subjected to first filtering;

performing time reversal operation on the first filtered step-state acceleration signal to obtain a first reversed step-state acceleration signal;

inputting the first step acceleration signal after the first inversion to a low-pass Butterworth filter to obtain a second filtered first step acceleration signal output by the low-pass Butterworth filter;

and performing time reversal operation on the second filtered first step acceleration signal to obtain a second reversed first step acceleration signal, wherein the second reversed first step acceleration signal is the filtered first step acceleration signal.

6. The wireless body area network of claim 1, wherein the coordinator node is specifically configured to:

low-pass filtering the first step state acceleration signal;

and respectively extracting first position information of the peak value and the valley value of the dimension-reduced first-step acceleration signal in the time domain and the frequency domain.

7. The wireless body area network of claim 6, wherein the coordinator node is specifically configured to:

extracting first position information of peak values and valley values of the first step state acceleration signals after dimension reduction and fast Fourier transform results of the first step state acceleration signals after dimension reduction based on a signed sliding window coding algorithm;

wherein, the process of the signed sliding window coding algorithm specifically comprises:

8. The wireless body area network of claim 1, wherein the wearable device is specifically configured to:

low-pass filtering the second step state acceleration signal;

and respectively extracting second position information of the peak value and the valley value of the dimension-reduced second-step acceleration signal in the time domain and the frequency domain.

9. The wireless body area network of claim 8, wherein the wearable device is specifically configured to:

extracting second position information of the peak value and the valley value of the second-step acceleration signal after dimension reduction and the fast Fourier transform result of the second-step acceleration signal after dimension reduction based on a signed sliding window coding algorithm;

10. A key distribution method of a wireless body area network is characterized in that a coordinator node of the wireless body area network is applied, an acceleration acquisition device is integrated with the coordinator node, and the coordinator node is in communication connection with at least one wearable device; the method comprises the following steps:

acquiring a first step state acceleration signal;

11. The key distribution method of the wireless body area network according to claim 10, wherein the generation process of the key to be distributed specifically comprises:

12. The key distribution method of claim 11, wherein the generating the key to be distributed according to the noise signal in the first step acceleration signal comprises:

extracting the noise signal in the first step-state acceleration signal;

coding the noise signal to obtain a secret key;

carrying out key enhancement operation on the key to obtain the key to be distributed;

the acceleration acquisition device is a three-axis acceleration sensor, and the noise signals comprise a first noise signal of an x axis, a second noise signal of a y axis and a third noise signal of a z axis;

the encoding the noise signal to obtain a key includes:

setting corresponding bits of a third binary random sequence as corresponding values according to the values of the bits in the third noise signal to obtain a third key;

if the kth bit in the noise signal is greater than or equal to 0, setting the kth bit of the binary random sequence as a first numerical value; if the kth bit in the noise signal is less than 0, setting the kth bit of the binary random sequence as a second numerical value, wherein k is an integer;

the performing a key enhancement operation on the key to obtain the key to be distributed includes:

performing exclusive-or operation on the first key, the second key and the third key to obtain the key to be distributed;

or, performing exclusive or operation on the first key, the second key and the third key to obtain an exclusive or key; and performing downsampling on the XOR key to obtain the key to be distributed.

13. The key distribution method of claim 12, wherein the extracting the noise signal from the first step acceleration signal comprises:

14. The key assignment method of claim 13, wherein the performing zero-phase filtering on the first step acceleration signal to obtain a filtered first step acceleration signal comprises:

15. The key distribution method of claim 10, wherein the extracting the first gait common information in the first step acceleration signal comprises:

low-pass filtering the first step state acceleration signal;

16. The key distribution method of claim 15, wherein the extracting the first position information of the peak and the valley of the dimension-reduced first step acceleration signal in the time domain and the frequency domain respectively comprises:

17. A key distribution method of a wireless body area network is characterized in that the key distribution method is applied to wearable equipment of the wireless body area network, the wearable equipment is integrated with an acceleration acquisition device, and the wearable equipment is in communication connection with a coordinator node; the method comprises the following steps:

18. The key assignment method of claim 17, wherein the extracting second gait common information in the second step acceleration signal comprises:

low-pass filtering the second step state acceleration signal;

19. The key distribution method of claim 18, wherein the extracting second position information of the peak and the valley of the dimension-reduced second step acceleration signal in the time domain and the frequency domain respectively comprises:

20. A key generation method of a wireless body area network is characterized in that the key generation method is applied to a coordinator node of the wireless body area network, the coordinator node is integrated with an acceleration acquisition device, and the method comprises the following steps:

acquiring a first step state acceleration signal;

extracting a noise signal in the first step state acceleration signal;

and generating a key to be distributed according to the noise signal.

21. The key generation method of claim 20, wherein the extracting the noise signal from the first step acceleration signal comprises:

22. The method of claim 21, wherein the performing zero-phase filtering on the first step acceleration signal to obtain a filtered first step acceleration signal comprises:

23. The key generation method of claim 20, wherein the generating a key to be distributed according to the noise signal comprises:

coding the noise signal to obtain a secret key;

the encoding the noise signal to obtain a key includes:

24. A coordinator node comprising an acceleration acquisition device, a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the method of any one of claims 10 to 16 or 20 to 23.

25. A wearable device comprising an acceleration acquisition apparatus, a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the method of any of claims 17 to 19.

26. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the method according to any one of claims 10 to 16 or 20 to 23 or 17 to 19.