CN108966223B

CN108966223B - Physical layer authentication method and system based on single-bit covert protocol

Info

Publication number: CN108966223B
Application number: CN201810404236.XA
Authority: CN
Inventors: 谢宁; 罗钢
Original assignee: Shenzhen University
Current assignee: Shenzhen University
Priority date: 2018-04-28
Filing date: 2018-04-28
Publication date: 2021-03-09
Anticipated expiration: 2038-04-28
Also published as: CN108966223A

Abstract

The utility model relates to a physical layer authentication method based on single-bit covert protocol, which is a covert analysis method of physical layer authentication of a wireless communication system comprising a transmitting terminal and a receiving terminal, and is characterized in that the method comprises the following steps: the transmitting end transmits a marking signal to a wireless channel based on a single-bit concealment protocol, wherein the marking signal comprises an authentication signal and an information signal, and in the single-bit concealment protocol, an energy distribution factor of the information signal is kept fixed and is an optimized value in an interval time period; a receiving end receives the marking signal, and processes the marking signal based on a single-bit concealment protocol to obtain the secret authentication probability; obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the signal-to-interference-and-noise ratio of the received information signal; and calculating the secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability and the secret authentication rejection probability to determine the secret level of the physical layer authentication.

Description

Physical layer authentication method and system based on single-bit covert protocol

Technical Field

The present disclosure relates to the field of wireless communication technologies, and in particular, to a physical layer authentication method and system based on a single-bit covert protocol.

Background

With the rapid spread of wireless devices, the need for transmitter authentication has also grown dramatically, and physical layer authentication has two major advantages over traditional authentication techniques based on upper layer cryptographic tools: first, physical layer authentication is relatively secure from an information theory perspective by allowing an illegitimate recipient to make only noisy observations of it to protect the tag. And secondly, the physical layer authentication enables a legal receiver to rapidly distinguish a legal transmitting section from an illegal transmitting section without finishing higher-layer processing. Authentication schemes for physical layer design can be generally classified into two broad categories, passive form and active form.

The focus here is on the initiative to embed the authentication signal in the message signal at the transmitting end and then extract the authentication signal at the receiving end. Common prior art techniques are: (1) the authentication signal is attached to the data using a time division multiplexing method, but this requires additional transmission time and easily exposes the authentication signal to an illegal receiving end because the authentication signal has the same signal-to-noise ratio (SNR) as the message signal; (2) for OFDM systems, loop smoothing signatures are generated by repeating certain message symbols on subcarriers according to an authentication signal, which wastes message throughput; (3) the frequency offset is modified according to the authentication signal, however, the rate of authentication signal transmitted per second is relatively low; (4) for pre-coded duobinary signaling systems, some of the initial bits are modified based on the authentication signal, which makes it challenging for the unknown received segment to recover the message signal, in violation of the concealment requirements.

The most widely used authentication technique currently is the authentication overlay (Auth-SUP) technique, which enables experimental results to be provided and analyzed through a software radio platform. Through analysis, the authentication superposition technology can overcome the defects of the four prior arts to a certain extent, and the requirements of effective authentication technology are met.

However, effective physical layer authentication techniques typically require consideration of both security, robustness and concealment. In particular, security generally means that an illegal receiving end cannot easily break the identity authentication through various attacks (including interference attack, replay attack, and simulation attack); robustness generally means that there is transmission in a random fading environment, and the authentication scheme can resist channel fading and noise effects; covertness typically means that the receiving segment is unable to detect that the authentication signal is anomalous without knowledge of the authentication scheme. Although the prior art has proposed a general physical layer authentication framework to comprehensively evaluate security and robustness, the prior art lacks quantitative analysis of the hidden level in terms of concealment due to its diversity and complexity, and has much room for improvement.

Disclosure of Invention

The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a physical layer authentication method and system based on a single-bit concealment protocol, which can better evaluate request delay and concealment performance.

To this end, a first aspect of the present disclosure provides a physical layer authentication method based on a single-bit concealment protocol, which is a physical layer authentication method of a wireless communication system including a transmitting end and a receiving end, and includes: the transmitting end transmits a mark signal to a wireless channel based on a single-bit concealment protocol, wherein the mark signal comprises an authentication signal and an information signal, and in the single-bit concealment protocol, an energy distribution factor of the information signal is kept fixed and is an optimized value in an interval time period; the receiving end receives the marking signal, and processes the marking signal based on the single-bit concealment protocol to obtain the secret authentication probability; obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the received signal-to-interference-and-noise ratio of the information signal; and calculating a secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability and the concealment authentication rejection probability to determine the concealment level of the physical layer authentication.

In the disclosure, the transmitting end transmits a mark signal based on a single-bit concealment protocol, the receiving end receives the mark signal, and Security Authentication Efficiency (SAE) is obtained through processing based on the single-bit concealment protocol. Wherein the single bit concealment protocol provides that the energy allocation factor of the information signal in the marker signal is kept fixed and at an optimized value for the interval period. In this case, the concealment level can be better evaluated based on the single-bit concealment protocol and a metric for physical layer authentication, privacy authentication efficiency (SAE).

In the physical layer authentication method according to the first aspect of the present disclosure, in the single-bit concealment protocol, the receiving end feeds back single-bit information of the snr threshold μ to the transmitting end, and sets

Let P _ACR0, wherein R_bRepresenting the regular signal rate. In this way,the feasibility of concealing the limits of physical layer authentication can be analyzed.

In the physical layer authentication method according to the first aspect of the present disclosure, the authentication is based on P_ACRThe optimum value of the energy allocation factor of the information signal is calculated as 0 as follows:

wherein the content of the first and second substances,

ε_ARTis the lower bound of the authentication request transmission probability, γ_bRepresenting the average signal-to-noise ratio, R_bRepresenting the regular signal rate. In this case, the single-bit concealment protocol can be optimized.

In the physical layer authentication method according to the first aspect of the present disclosure, the channel assumption condition is that there is a single-bit feedback of the channel state information of the receiving end. In this case, the concealment performance can be better evaluated based on a single-bit concealment protocol.

In the physical layer authentication method according to the first aspect of the present disclosure, the secret authentication efficiency is calculated by the following formula (ii): eta is P_ART(1-P_ACR)P_SA(II) wherein P_ARTRepresenting the transmission probability of said authentication request, P_ACRRepresenting the covert authentication rejection probability, P_SARepresenting the secret authentication probability. This enables the determination of the concealment level of physical layer authentication.

In the physical layer authentication method according to the first aspect of the present disclosure, the signal to interference plus noise ratio of the information signal is calculated by the following formula (iii):

wherein the content of the first and second substances,

an energy distribution factor representing the information signal,

indicating the authenticationEnergy allocation factor of the signal, the tag signal being sent in blocks, gamma_b,iRepresenting the signal-to-noise ratio, h, of the i-th block of the mark signal at the receiving end_b,iIndicating the channel gain of the i-th block flag signal,

representing the noise variance at the receiving end. Thus, the concealment authentication rejection probability can be obtained, and the concealment level of the physical layer authentication can be determined. A second aspect of the present disclosure provides a physical layer authentication apparatus based on a single-bit concealment protocol, including: a processor that executes the computer program stored by the memory to implement the physical layer authentication method of any one of the above; and a memory.

A third aspect of the present disclosure provides a computer-readable storage medium, wherein the computer-readable storage medium stores at least one instruction, and the at least one instruction when executed by a processor implements the physical layer authentication method of any one of the above.

A fourth aspect of the present disclosure provides a physical layer authentication system based on a single-bit covert protocol, comprising: a transmitting device which transmits a marker signal to a wireless channel based on a single-bit concealment protocol, the marker signal including an authentication signal and an information signal, in the single-bit concealment protocol, an energy allocation factor of the information signal is kept fixed and an optimized value in an interval period; a receiving device, comprising: the processing module receives the marking signal, processes the marking signal based on the single-bit concealment protocol and obtains the secret authentication probability; the calculation module is used for obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the signal-to-interference-and-noise ratio of the received information signal; and the judging module is used for calculating the secret authentication efficiency according to the secret authentication probability, the authentication request transmission probability and the probability of the secret authentication rejection so as to determine the secret level of the physical layer authentication.

In the disclosure, the transmitting apparatus transmits a marker signal based on a single-bit concealment protocol, and the receiving apparatus receives the marker signal, and performs a process based on the single-bit concealment protocol to obtain a Secret Authentication Efficiency (SAE). Wherein the single bit concealment protocol provides that the energy allocation factor of the information signal in the marker signal is kept fixed and at an optimized value for the interval period. In this case, the concealment level can be better evaluated based on the single-bit concealment protocol and a metric for physical layer authentication, privacy authentication efficiency (SAE).

In the physical layer authentication system according to the fourth aspect of the present disclosure, in the single-bit concealment protocol, the receiving end feeds back the snr threshold μ to the transmitting end, and sets the snr threshold μ

Let P _ACR0, wherein R_bRepresenting the regular signal rate. This makes it possible to analyze the feasibility of concealing the restrictions of physical layer authentication.

In the physical layer authentication system according to the fourth aspect of the present disclosure, the authentication is based on P_ACRThe optimum value of the energy allocation factor of the information signal is calculated as 0 as follows:

wherein the content of the first and second substances,

In the physical layer authentication system according to the fourth aspect of the present disclosure, the channel assumption condition is that there is a single-bit feedback of the channel state information of the receiving apparatus. In this case, the concealment performance can be better evaluated based on a single-bit concealment protocol.

In the physical layer authentication system according to the fourth aspect of the present disclosure, in the determination module, the secret authentication efficiency is calculated by the following formula (ii): eta is P_ART(1-P_ACR)P_SA(II) wherein P_ARTRepresenting the transmission probability of said authentication request, P_ACRRepresenting the covert authentication rejection probability, P_SARepresenting a secret authentication probability. This enables the determination of the concealment level of physical layer authentication.

In the physical layer authentication system according to the fourth aspect of the present disclosure, in the calculation module, the signal to interference plus noise ratio of the information signal is calculated by the following formula (iii):

wherein the content of the first and second substances,

an energy distribution factor representing the information signal,

an energy distribution factor representing the authentication signal, the signature signal being sent in blocks, gamma_b,iRepresenting the signal-to-noise ratio, h, of the i-th block mark signal at said receiving means_b,iIndicating the channel gain of the i-th block flag signal,

representing the noise variance of the receiving means. Thus, the concealment authentication rejection probability can be obtained, and the concealment level of the physical layer authentication can be determined. Compared with the prior art, the examples of the present disclosure have the following beneficial effects:

in the prior art, due to the diversity and complexity of the system and the lack of quantitative analysis of the concealment level, the disclosure designs a single-bit concealment protocol and provides a new measure for physical layer authentication, namely, the privacy authentication efficiency (SAE), so that the concealment performance of the physical layer authentication can be better evaluated.

Drawings

Fig. 1 is a signal authentication diagram illustrating a physical layer authentication method according to an example of the present disclosure.

Fig. 2 is a flow diagram illustrating a physical layer authentication method in accordance with an example of the present disclosure.

Fig. 3 is a schematic diagram illustrating a structure of a physical layer authentication method transmitting end transmission signal according to an example of the present disclosure.

Fig. 4 is a waveform diagram illustrating a receiving-end secret authentication efficiency of a physical layer authentication method according to an example of the present disclosure.

Fig. 5 is a waveform diagram illustrating an illegal receiver-side secret authentication efficiency waveform of a physical layer authentication method according to an example of the present disclosure.

Fig. 6 is a schematic diagram illustrating a physical layer authentication system architecture to which examples of the present disclosure relate.

Fig. 7 is a schematic diagram illustrating a physical layer authentication system receiving device signal processing module according to an example of the present disclosure.

Fig. 8 is a schematic diagram showing a structure of a physical layer authentication device according to an example of the present disclosure.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same components are denoted by the same reference numerals, and redundant description thereof is omitted. The drawings are schematic and the ratio of the dimensions of the components and the shapes of the components may be different from the actual ones.

It should be noted that the terms "first," "second," "third," and "fourth," etc. in the description and claims of the present disclosure and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

In addition, the headings and the like referred to in the following description of the present disclosure are not intended to limit the content or scope of the present disclosure, but merely serve as a reminder for reading. Such a subtitle should neither be understood as a content for segmenting an article, nor should the content under the subtitle be limited to only the scope of the subtitle.

The present disclosure provides a physical layer authentication method, device and system based on a single-bit covert protocol. In the present disclosure, request delay and concealment performance of physical layer authentication can be evaluated more accurately. The present disclosure is described in detail below with reference to the attached drawings.

Fig. 1 is a signal model diagram illustrating a physical layer authentication method to which examples of the present disclosure relate.

As shown in fig. 1, the physical layer authentication method, apparatus and system based on the single bit concealment protocol may be a physical layer authentication method, apparatus and system of a wireless communication system having a transmitting end and a receiving end. The receiving end may include a legal receiving end and an illegal receiving end.

In some examples, as shown in fig. 1, the transmitting end is used to transmit signals to a wireless channel. The transmitting end is usually the legitimate sender. The transmitting end may also include an illegal sender. The transmitting end mentioned below refers to the legitimate sender. The receiving end receives the signal transmitted by the transmitting end. Because the receiving end can comprise a legal receiving end and an illegal receiving end, the signal transmitted by the transmitting end can be received by the legal receiving end and can also be received by the illegal receiving end.

In some examples, the receiver may be a test receiver. The test receiving end generally refers to a receiving end for detecting a transmission signal of the transmitting end. For example, the test receiving end may be a test device for detecting a signal transmitted by the transmitting end in a scenario of simulating a wireless channel in daily life. The test receiving end may include a legal receiving end and an illegal receiving end.

In some examples, the number of the transmitting ends may be two or more, and the number of the receiving ends may be two or more, specifically, the number of the legal receiving ends may be two or more, and the number of the illegal receiving ends may be two or more.

In some examples, as shown in fig. 1, in the presence of an illegal receiving end, the transmitting end sends an authentication request, and the legal receiving end feeds back a signal-to-noise ratio threshold to the transmitting end.

In some examples, the transmitting end as in the signal model of fig. 1 described above may include a base station or a user equipment. A base station (e.g., access point) can refer to a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminals. The base station may be configured to interconvert received air frames and IP packets as a router between the wireless terminal and the rest of the access network, which may include an Internet Protocol (IP) network. The base station may also coordinate management of attributes for the air interface. For example, the Base Station may be a Base Transceiver Station (BTS) in GSM or CDMA, a Base Station (NodeB) in WCDMA, or an evolved Node B (NodeB or eNB or e-NodeB) in LTE.

In some examples, the user Device may include, but is not limited to, a smartphone, a laptop, a Personal Computer (PC), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), a wearable Device (e.g., a smart watch, a smart bracelet, smart glasses), and various other electronic devices, wherein an operating system of the user Device may include, but is not limited to, an Android operating system, an IOS operating system, a Symbian operating system, a blackberry operating system, a Windows Phone8 operating system, and so on.

In some examples, the receiving end may include a base station. A base station (e.g., access point) can refer to a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminals. The base station may be configured to interconvert received air frames and IP packets as a router between the wireless terminal and the rest of the access network, which may include an Internet Protocol (IP) network. The base station may also coordinate management of attributes for the air interface. For example, the Base Station may be a Base Transceiver Station (BTS) in GSM or CDMA, a Base Station (NodeB) in WCDMA, or an evolved Node B (NodeB or eNB or e-NodeB) in LTE.

In other examples, the receiving end may further include a user device or a test device. The user Device or the test Device may include, but is not limited to, various electronic devices such as a smart phone, a notebook Computer, a Personal Computer (PC), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), a wearable Device (e.g., a smart watch, a smart bracelet, and smart glasses), and the like. The operating system of the user equipment or the test equipment may include, but is not limited to, an Android operating system, an IOS operating system, a Symbian operating system, a Black Berry operating system, a Windows Phone8 operating system, and the like.

Fig. 2 is a flow diagram illustrating a physical layer authentication method in accordance with an example of the present disclosure. Fig. 3 is a schematic diagram illustrating a structure of a physical layer authentication method transmitting end transmission signal according to an example of the present disclosure.

In some examples, a physical layer authentication method based on a single bit covert protocol (sometimes referred to simply as a "physical layer authentication method") is a physical layer authentication method for a wireless communication system having a transmitting end and a receiving end. The receiving end may include a legal receiving end and an illegal receiving end. In addition, in the following description, an illegal receiving end is sometimes also referred to as a listening end.

In addition, based on the signal model shown in fig. 1, as shown in fig. 2, the physical layer authentication method based on the single-bit concealment protocol includes the step of transmitting a marker signal to the wireless channel based on the single-bit concealment protocol, wherein the marker signal includes an authentication signal and an information signal, and the energy allocation factor of the information signal is kept fixed and at an optimized value for an interval period in the single-bit concealment protocol (step S110).

In step S110, the assumed channel condition of the physical layer authentication method may be that the channel state information of the receiving end has a single bit, that is, the transmitting end knows the single-bit channel state information fed back by the receiving end. Specifically, as described above, the receiving end may include a legitimate receiving end and an illegitimate receiving end. In a general communication process, an illegal receiving end does not feed back channel state information to a transmitting end, and a legal receiving end feeds back the channel state information to the transmitting end. I.e., the transmitting end may not know any channel state information about the illegal receiving end, while the transmitting end may know the single-bit channel state information feedback of the legal receiving end. However, under the channel assumption condition of the physical layer authentication method, that is, under the condition that the channel state information of the illegal receiving end is unknown and the channel state information of the legal receiving end has single-bit feedback, the concealment performance of the physical layer authentication can be better evaluated by the physical layer authentication method disclosed by the present disclosure.

In some examples, the Channel State Information (CSI) may be a Channel property of the communication link. For example, the channel state information may be signal scattering, environmental attenuation, distance attenuation, and the like.

In some examples, the transmitting end may transmit a marker signal to the wireless channel based on the signal model described above. I.e. the transmitting end may send an authentication request. As shown in fig. 3, the signature signal may include an authentication signal and an information signal. The authentication signal may reflect key knowledge shared between the transmitting end and the legitimate receiving end. The information signal may reflect the information to be communicated. The authentication signal may be superimposed on the information signal. The marker signal may be transmitted in blocks. The marker signal can be calculated by the following formula (1):

x_i＝ρ_ss_i+ρ_tt_i (1)

wherein x is_iIndicating the i-th block mark signal, s_iRepresenting the i-th block information signal, t_iIndicating the i-th block authentication signal. In addition, the first and second substrates are,

represents the energy allocation factor of the message signal,

representing the energy distribution factor of the authentication signal.

The present embodiment is not limited thereto, and the transmitting end may transmit a normal signal to the wireless channel. No authentication included in regular signalsA signal. I.e. the energy distribution factor of the authentication signal

Is zero, then the regular signal can be represented as x_i＝s_i. In addition, the rate of the regular signal can be set to R_b。

In some examples, the protocol to which the physical layer authentication method conforms may be a single bit concealment protocol. In addition, under the above-mentioned channel assumption conditions, the single-bit concealment protocol is effective for the physical layer optimized concealment analysis method of the present disclosure. The single-bit concealment protocol specifies an energy allocation factor for an information signal

And remain fixed for the interval period. That is, when the transmitting end transmits the tag signal to the wireless channel, the energy distribution factor of the information signal in the tag signal is kept fixed in the interval period. In other words, the single-bit concealment protocol specifies that the transmitting end maintains a fixed energy allocation factor for the inter-period

An authentication request is sent. Wherein the energy distribution factor of the information signal

May be referred to as authentication protocol parameters.

In some examples, the energy distribution factor remains fixed for the interval period

Representing energy distribution factor

Not constant throughout the communication. Energy distribution factor at different time periods

Can be different whenThe energy distribution factor within the time segment may remain fixed.

In other examples, the single-bit concealment protocol further specifies an energy allocation factor for the information signal

Within the interval period is an optimized value. I.e. the energy distribution factor of the information signal within the time segment

May be an energy allocation factor optimized value for the corresponding time period.

In this case, it is the energy distribution factor

The optimum value is constant throughout the communication, and the energy allocation factor is the same for different time periods. I.e. energy distribution factor throughout the communication

Constant and at an optimum value. In addition, energy distribution factor over different time periods

Or may be different. Energy distribution factor

The acquisition of the optimized value is described in detail later.

In step S110, the transmitting end transmits a marker signal to the wireless channel based on a single bit concealment protocol. I.e. the tag signal is transmitted into the radio channel by the transmitting end. Wherein the wireless channel has a channel gain h. The marker signal transmitted over the wireless channel may include a channel gain h.

In some examples, the physical layer authentication method based on the single-bit concealment protocol may further include the receiving end receiving the token signal, and performing correlation processing on the token signal based on the single-bit concealment protocol to obtain the secret authentication probability (step S120).

In step S120, since the mark signal in step S110 is transmitted in blocks, the mark signal may be received in blocks by the receiving end. Since the receiving end may include a legal receiving end and an illegal receiving end, receiving a signal in the wireless communication system may include a legal receiving end and an illegal receiving end. The tag signal received by the legal receiving end and passing through the wireless channel can be calculated by the following formula (2):

y_b,i＝h_b,ix_i+n_b,i (2)

wherein h is_b,iIndicating the channel gain of the i-th block of the mark signal received by the legal receiving end. n is_b,iRepresenting the noise of the legitimate receiver. In addition, h_b,iObey a mean variance of 0 to

Complex gaussian distribution. n is_b,iObey a mean variance of 0 to

Complex gaussian distribution.

In some examples, since the mark signal may be received by the receiving ends (including a legal receiving end and an illegal receiving end) in blocks, the channel signal-to-noise ratio of each block of mark signal measured by the legal receiving end may be calculated by the following equation (3):

wherein the content of the first and second substances,

representing the noise variance at the legitimate receiver. In addition, the average signal-to-noise ratios of the marker signals measured by the legal receiving end can be calculated by the following formula (4):

in addition, in some examples, the tag signal received by the illegal receiving end through the wireless channel, the channel signal-to-noise ratio of each tag signal measured by the illegal receiving end, and the average signal-to-noise ratio of the tag signal measured by the illegal receiving end may be analogous to the above calculation manner of the legal receiving end.

In some examples, the receiving end may perform channel estimation, that is, the legitimate receiving end and the illegitimate receiving end may perform channel estimation. Through channel estimation, a legal receiving end and an illegal receiving end can estimate the received mark signal y transmitted through a wireless channel_iTarget mark signal in

In some examples, since the legitimate receiver knows the single-bit concealment protocol and the illegitimate receiver does not know the single-bit concealment protocol, the legitimate receiver can further process the target mark signal based on the single-bit concealment protocol

The receiving side involved in the signal processing is a legitimate receiving side unless otherwise specified.

In some examples, a single-bit concealment protocol sets an energy allocation factor for an information signal

Is determined (i.e. the energy distribution factor of the first time segment)

Value) of

So that the energy distribution factor rho of the authentication signal_t ²May also be determined. Therefore it is known

And

under the condition of (3), the receiving end can extract the target mark signal

Of the residual signal r_i. In addition, energy distribution factor

Can be optimized, and the energy distribution factor set in the single-bit concealment protocol from the second time period (including the second time period)

The optimized energy distribution factor can also be given

The value is obtained. This enables the single-bit concealment protocol to be optimized.

In some examples, the receiving end acquires a residual signal r_iThe residual signal r can then be further determined_iWhether or not to include the authentication signal t_i. The receiving end can feed back single-bit information of the signal-to-noise ratio threshold value mu of the marking signal to the transmitting end according to the judgment result. Since the feedback of the receiving end is based on the single-bit concealment protocol, the receiving end can feed back the single-bit information of the signal-to-noise ratio threshold mu to the transmitting end based on the single-bit concealment protocol. That is, in the single-bit concealment protocol, the receiving end feeds back the single-bit information of the snr threshold μ to the transmitting end. In addition, the signal-to-noise ratio threshold value mu is feasible within a certain range under the single-bit concealment protocol. The obtaining of the feasible range of the signal-to-noise ratio threshold μ is described in detail later.

In addition, in some examples, the receiving end may determine the residual signal r_iWhether or not to include the authentication signal t_i. The receiving end can obtain the false alarm Probability (PFA) and the detection according to the judged resultMeasurement rate (PD). The security authentication Probability (PSA) can be derived based on the detection rate (PD) under the constraint of the false alarm Probability (PFA). The secret authentication Probability (PSA) can be calculated by the following equation (5):

P_SA＝max{P_D,1-P_D,2,0} (5)

wherein, P_D,1Indicating the detection rate, P, of a legitimate receiver_D,2Indicating the detection rate of the illegal receiving end. Therefore, the condition that the mark signal is monitored by an illegal receiving end can be determined through the secret authentication Probability (PSA).

In some examples, the physical layer authentication method may further include obtaining an authentication request transmission probability and a concealed authentication rejection probability based on a signal to interference and noise ratio of the received information signal (step S130).

In step S130, the signal-to-interference-plus-noise ratio (MINR) of the label signal received by the receiving end is calculated by the following formula (6):

wherein the content of the first and second substances,

representing the energy division factor of the information signal.

Representing the energy distribution factor of the authentication signal. Since the marking signal is transmitted in blocks, gamma_b,iIndicating the channel signal-to-noise ratio at the receiving end of the ith block. h is_b,iIndicating the channel gain of the i-th block mark signal received by the receiving end.

In some examples, the energy division factor of the authentication signal is determined if the signal transmitted by the transmitting end is a regular signal, i.e., the signal transmitted by the transmitting end does not include the authentication signal

To zero, energy distribution of the information signalFactor(s)

Is 1. In this way,

if the signal transmitted by the transmitting terminal is a mark signal, the energy distribution factor of the signal is authenticated

Is not zero, and as can be seen from the formula (6), the signal to interference and noise ratio (MINR) when the transmitting end transmits the marking signal is smaller than the signal to interference and noise ratio (MINR) when the transmitting end transmits the conventional signal, so that the signal to interference and noise ratio (MINR) satisfies the requirement when the transmitting end transmits the marking signal

In addition, the authentication request transmission Probability (PART) may be obtained from the signal to interference and noise ratio (MINR) described above. The authentication request transmission Probability (PART) can be calculated by the following equation (7):

thus, the performance of the authentication transmission request delay can be measured according to the authentication request transmission Probability (PART).

In some examples, based on the channel assumption condition in step S110 above, to maintain the concealment requirement, the signal-to-noise threshold μ is set such that the signal-to-noise threshold satisfies

The authentication request transmission Probability (PART) shown in equation (8) can be obtained by combining equation (7):

wherein R is_bRepresenting the regular signal rate.

In some examples, under a single-bit concealment protocol, the value of the authentication request transmission Probability (PART) needs to be satisfied

Wherein epsilon_ARTIs a lower bound of a transmission Probability of Authentication Request (PART) and satisfies 0 ≦ ε_ART≤ε_ART1. Wherein epsilon_ART1Satisfy the requirement of

Based on the constraint condition of the authentication request transmission Probability (PART), the feasible range of the signal-to-noise ratio threshold value mu fed back by the receiving end can be obtained, that is, the feasible range is

In addition, in some examples, an authentication concealment rejection event may occur at the receiving end when the information signal in the marker signal cannot be decoded without error at the receiving end. The Probability of concealment of authentication at this time (PACR) can be regarded as the Probability of concealment of authentication under the condition of transmission Probability of Authentication Request (PART). The authentication concealment rejection probability is also called the concealment authentication rejection probability. The concealed authentication rejection Probability (PACR) may be derived from the signal to interference and noise ratio (MINR) described above. The concealed authentication rejection Probability (PACR) can be calculated by the following equation (9):

in some examples, the signal-to-noise threshold μ is set such that the signal-to-noise threshold is satisfied

It is possible to obtain by deforming it,

in this case, the bond (9) can result in P _ACR0. ByHere, it can be seen that when the information signal in the marker signal cannot be decoded without error at the receiving end, the receiving end is unlikely to have an authentication concealment rejection event. I.e. any covert constraint is feasible.

In addition, under a single-bit covert protocol, the covert authentication rejection Probability (PACR) needs to meet

Wherein epsilon_ACRIs an upper bound on the concealed authentication rejection Probability (PACR) that satisfies 0 ≦ ε_ACRLess than or equal to 1. Thus, the concealment level of the physical layer authentication technique can be measured based on the concealment authentication Probability (PACR).

In some examples, based on the constraint of the concealed authentication rejection Probability (PACR), the feasible range of the snr threshold μ fed back by the receiving end, i.e. the feasible range of the snr threshold μ, can be obtained

Wherein the content of the first and second substances,

therefore, the feasible range of the signal-to-noise ratio threshold μ fed back by the receiving end under the single-bit concealment protocol can be obtained by combining the above constraint of the transmission probability of the authentication request (PART) and the constraint of the concealment authentication rejection Probability (PACR).

Additionally, in some examples, under a single-bit concealment protocol, based on P as described above_ACRConstraint condition of 0 to satisfy

Energy distribution factor optimized by the following formula (10)

Wherein the content of the first and second substances,

in some examples, the physical layer authentication method may further include calculating a secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability, and the covert authentication rejection probability to determine a covert level of the physical layer authentication (step S140).

In step S140, the secret authentication Probability (PSA), the authentication request transmission Probability (PART), and the covert authentication rejection Probability (PACR) may be obtained through the above-described steps S120 and S130.

In some examples, a Secret Authentication Efficiency (SAE) is calculated based on a secret authentication Probability (PSA), an authentication request transmission Probability (PART), and a covert authentication rejection Probability (PACR).

In some examples, the specified Security Authentication Efficiency (SAE) may be calculated by the following equation (11):

η＝P_ART(1-P_ACR)P_SA (11)

wherein, P_ARTIndicating authentication request transmission Probability (PART), P_ACRRepresenting the concealed authentication rejection Probability (PACR), P_SARepresenting the secret authentication Probability (PSA). η denotes the Secret Authentication Efficiency (SAE). In addition, the condition for the Secret Authentication Efficiency (SAE) to have a non-zero positive value is that the feasible range of the above SNR threshold μ is satisfied while the requirement for satisfying the above requirement

In some examples, the Secure Authentication Efficiency (SAE) includes an authentication request transmission Probability (PART) that can evaluate a request delay for physical layer authentication and a covert authentication reject Probability (PACR). The covert authentication rejection Probability (PACR) may determine the level of concealment of physical layer authentication. Thus, the privacy authentication efficiency (SAE) may better evaluate request delay and concealment levels.

Additionally, in some examples, at an optimized energy allocation factor

And a signal-to-noise ratio threshold μ within a feasibility range, the Secret Authentication Efficiency (SAE) constrained by the authentication request transmission Probability (PART) and the covert authentication rejection Probability (PACR) gets a maximum. Specifically, the relationship of the maximum value of the Secret Authentication Efficiency (SAE), the transmission probability of the authentication request (PART), and the concealed authentication rejection Probability (PACR) is obtained by the following equation (12):

wherein epsilon_ACRIs the upper bound of the concealed authentication rejection Probability (PACR), and ε_ARTIs the lower bound of the authentication request transmission Probability (PART), R_bRepresenting the regular signal rate.

In some examples, the transmitting end transmits the marker signal based on a single bit concealment protocol, and the receiving end receives the marker signal, and the Security Authentication Efficiency (SAE) is obtained through processing based on the single bit concealment protocol. Wherein the single bit concealment protocol provides that the energy allocation factor of the information signal in the marker signal is kept fixed during the interval period. In this case, the concealment level can be better evaluated based on the single-bit concealment protocol and a metric for physical layer authentication, privacy authentication efficiency (SAE).

In some examples, as shown in fig. 4, under the single-bit concealment protocol, the Secret Authentication Efficiency (SAE) is always zero when the signal-to-noise ratio of the receiving end is less than or equal to 15dB, and the Secret Authentication Efficiency (SAE) rapidly increases and approaches 1 as the signal-to-noise ratio of the receiving end continues to increase.

According to the figure, under the non-single-bit concealment protocol, the energy distribution factor of the information signal

When the constant is 0.9, and the signal-to-noise ratio of the receiving end is less than or equal to 17dB, the Security Authentication Efficiency (SAE) is always zero. As the signal-to-noise ratio at the receiving end continues to increase, the Security Authentication Efficiency (SAE) increases rapidly and approaches 1. Energy distribution factor of information signal

When the signal-to-noise ratio is constant to 0.8 and is less than or equal to 24dB at the receiving end, the Security Authentication Efficiency (SAE) is always zero. As the signal-to-noise ratio at the receiving end continues to increase, the Security Authentication Efficiency (SAE) increases rapidly and approaches 1.

As can be seen from the figure, the signal-to-noise ratio requirement for the receiving end under the single-bit concealment protocol is lower than that for the non-single-bit concealment protocol, and therefore, the single-bit concealment protocol is more superior when the signal-to-noise ratio of the receiving end is lower.

In some examples, as shown in fig. 5, under the single-bit concealment protocol, when the signal-to-noise ratio of the illegal receiving end is less than or equal to 17dB, the Secret Authentication Efficiency (SAE) is close to 1 and does not change much, when the signal-to-noise ratio of the illegal receiving end continues to increase, the Secret Authentication Efficiency (SAE) rapidly decreases and is close to 0, and when the signal-to-noise ratio of the subsequent illegal receiving end continues to increase, the Secret Authentication Efficiency (SAE) slowly decreases to 0.

When the signal-to-noise ratio is constant at 0.9 and is less than or equal to 15dB, the Secret Authentication Efficiency (SAE) is close to 1 and does not change greatly. The Secret Authentication Efficiency (SAE) decreases rapidly and approaches 0 as the snr of the illegal receiver continues to increase, and decreases slowly to 0 as the snr of the subsequent illegal receiver continues to increase. Energy distribution factor of information signal

Constant at 0.8, Secret Authentication Efficiency (SAE) of illegal receiving end is oneThe length is 0.

The physical layer authentication method based on the single-bit concealment protocol is more effective by comprehensively considering different requirements of a legal receiving end and an illegal receiving end, for example, different requirements of Security Authentication Efficiency (SAE) of the legal receiving end and the illegal receiving end.

Fig. 6 is a schematic diagram illustrating a physical layer authentication system architecture to which examples of the present disclosure relate. Fig. 7 is a schematic diagram illustrating a physical layer authentication system receiving device signal processing module according to an example of the present disclosure.

In some examples, the physical layer authentication system based on a single bit covert protocol is a physical layer authentication system of a wireless communication system having a transmitting device and a receiving device. Wherein, the receiving device may include a legal receiving device and an illegal receiving device. In addition, the transmitting apparatus and the transmitting end in the present disclosure may be the same concept, and the receiving apparatus and the receiving end may be the same concept.

In some examples, as shown in fig. 6, a physical layer authentication system 1 based on a single-bit covert protocol (physical layer authentication system 1 for short) may include a transmitting apparatus 10 and a receiving apparatus 20. The reception apparatus 20 may include a legal reception apparatus and an illegal reception apparatus.

In some examples, the transmitting device 10 transmits a marker signal to the wireless channel based on a single-bit concealment protocol in which the energy allocation factor of the information signal is kept fixed and at an optimum value for an interval period, the marker signal including an authentication signal and the information signal.

In some examples, the channel assumption condition of the physical layer authentication system 1 in which the transmitting apparatus 10 is located may be a case where a single bit of channel state information exists in the receiving end, that is, the transmitting end knows the single bit of channel state information fed back by the receiving end. Specifically, the channel assumption conditions in step S110 can be analogized.

In some examples, the transmitting device 10 transmits a marker signal to a wireless channel. I.e. the transmitting device 10 may send an authentication request. The signature signal may include an authentication signal and an information signal. The authentication signal may reflect key knowledge shared between the transmitting device 10 and a legitimate receiving device. The information signal may reflect the information to be communicated. The authentication signal may be superimposed on the information signal. The marker signal may be transmitted in blocks. The labeling signal may be as shown in equation (1). The present embodiment is not limited thereto, and the transmitting device 10 may transmit a normal signal to a wireless channel. The authentication signal is not included in the regular signal.

In some examples, a single-bit concealment protocol is set based on the channel assumption conditions described above. The protocol followed by the transmitting device 10 in transmitting the marker signal to the wireless channel may be a single bit concealment protocol. The single-bit concealment protocol specifies an energy allocation factor for an information signal

An authentication request is sent. As shown in fig. 6, the solid line indicates that the transmitting device 10 transmits the authentication request. Wherein the energy distribution factor of the information signal

May be referred to as authentication protocol parameters.

Representing energy distribution factor

The energy distribution factor over the time period may be kept fixed, which may be different.

In some examples, the single-bit concealment protocol further specifies an energy allocation factor for the information signal

Or the energy distribution factor in the corresponding time period

And (6) optimizing the value. Energy distribution factor

Obtaining the optimized value is analogous to the optimized energy distribution factor in the physical layer authentication method

The method of (1).

In some examples, the transmitting device 10 transmits the marker signal to the wireless channel based on a single-bit covert protocol. Wherein the wireless channel has a channel gain h. The marker signal transmitted over the wireless channel may include a channel gain h.

In some examples, an illegal receiving device is generally unable to process the received signature signal for covert analysis, since the illegal receiving device does not know the single bit covert protocol and does not have shared key knowledge with the transmitting device 10. The receiver 20 to be used in the signal processing is a legitimate receiver unless otherwise specified.

In some examples, as shown in fig. 6, the physical layer authentication system 1 may further include a receiving device 20. The receiving means 20 may be used to receive and process the marker signal via a wireless channel. The receiving apparatus 20 feeds back single-bit information of the signal-to-noise ratio threshold μ to the transmitting apparatus 10. As shown in fig. 6, the dashed line represents the feedback of the receiving apparatus 20 to the transmitting apparatus 10.

In some examples, as shown in fig. 7, the receiving apparatus 20 may include a processing module 21. The processing module 21 receives the token signal and processes the token signal based on a single bit concealment protocol to obtain a security authentication Probability (PSA).

In some examples, since the marker signal transmitted by the transmitting device 10 is transmitted in blocks, the marker signal may be received in blocks by the receiving device 20. The marker signal can also be received in blocks due to illegal receiving means. Therefore, the flag signal received by the processing module 21 in the receiving apparatus 20 is as shown in equation (2).

In some examples, the processing module 21 in the reception apparatus 20 and the illegal reception apparatus may perform channel estimation. By channel estimation, the processing module 21 and the illegal receiving means can estimate the received marking signal y transmitted via the wireless channel_iTarget mark signal in

In addition, the SNR of each block of the mark signal received by the processing module 21 can be represented by equation (3). The average SNR of the received marking signals of the processing module 21 can be shown as equation (4).

In some examples, since receiving apparatus 20 knows the single-bit concealment protocol and an illegal receiving apparatus does not know the single-bit concealment protocol, processing module 21 of receiving apparatus 20 may further process the target mark signal based on the single-bit concealment protocol

Is determined (i.e. the energy distribution factor of the first time segment)

Value) of

Energy distribution factor of authentication signal

May also be determined. Therefore it is known

And

Of the residual signal r_i. In addition, energy distribution factor

The optimized energy distribution factor can also be given

In some examples, the processing module 21 obtains the residual signal r_iThe residual signal r can then be further determined_iWhether or not to include the authentication signal t_i. The receiving device 20 may feed back the threshold value μ of the signal-to-noise ratio of the marker signal to the transmitting device 10 according to the result of the determination. That is, the receiving apparatus 20 can feed back the information to the transmitting apparatus 10 based on the single-bit concealment protocolSingle bit information of the noise ratio threshold μ. That is, in the single-bit concealment protocol, the receiving apparatus feeds back single-bit information of the signal-to-noise ratio threshold μ to the transmitting apparatus. The feasible range of the snr threshold μmay be analogous to the acquisition of the snr threshold μ in the above-mentioned physical layer authentication method.

Additionally, in some examples, the receiving apparatus 20 may determine the residual signal r_iWhether or not to include the authentication signal t_i. The reception device 20 can obtain the false alarm Probability (PFA) and the detection rate (PD) based on the result of the judgment. A security authentication Probability (PSA) can be derived based on the detection rate (PD). The secret authentication Probability (PSA) may be as shown in equation (5).

In some examples, as shown in fig. 7, the receiving apparatus 20 may include a computing module 22. The calculation module 22 obtains an authentication request transmission probability and a concealed authentication rejection probability based on the signal-to-interference-and-noise ratio of the received information signal.

In some examples, the signal-to-interference-and-noise ratio (MINR) of the marker signal received by the prescribed receiving device 20 may be as shown in equation (6). If the signal transmitted by the transmitting device 10 is a regular signal, i.e. the signal transmitted by the transmitting device 10 does not comprise an authentication signal, the energy distribution factor of the authentication signal

Zero, energy distribution factor of the information signal

Is 1. In this way,

if the signal emitted by the emitting device 10 is a marking signal, the energy distribution factor of the authentication signal

In addition, the authentication request transmission Probability (PART) may be obtained from the signal to interference and noise ratio (MINR) described above. The authentication request transmission Probability (PART) may be as shown in equation (7). The authentication request transmission Probability (PART) can measure the performance of the authentication transmission request delay. In some examples, since the physical layer authentication system 1 is based on the above-described channel assumption condition, in order to maintain the concealment requirement, the signal-to-noise ratio threshold μ is set so that the signal-to-noise ratio threshold satisfies

The combination formula (7) can obtain the authentication request transmission Probability (PART) shown in the formula (8).

In addition, in some examples, an authentication concealment rejection event may occur at the receiving apparatus 20 when the information signal in the marker signal cannot be decoded without error at the receiving apparatus 20. The concealed authentication rejection Probability (PACR) may be derived from the signal to interference and noise ratio (MINR) described above. The concealed authentication rejection Probability (PACR) may be as shown in equation (9).

It is possible to obtain by deforming it,

in this case, the bond (9) can result in P _ACR0. Thus, it can be seen that when the information signal in the marker signal cannot be decoded without error at the receiving end, the receiving end is unlikely to have an authentication concealment rejection event. I.e. any covert constraint is feasible.

Wherein epsilon_ACRIs the upper bound of the concealed authentication rejection Probability (PACR), which satisfies ε_ACRLess than or equal to 1. Thus, the concealment level of the physical layer authentication technique can be measured based on the concealment authentication Probability (PACR).

Additionally, in some examples, under a single-bit concealment protocol, based on P _ACR0 and

optimized energy distribution factor obtained by equation (10)

In some examples, as shown in fig. 7, the receiving apparatus 20 may include a determination module 23. The decision module 23 calculates the secret authentication efficiency from the secret authentication probability, the authentication request transmission probability and the concealment authentication rejection probability to determine the request delay and concealment level of physical layer authentication.

Additionally, in some examples, the secure authentication Probability (PSA), the authentication request transmission Probability (PART), and the covert authentication rejection Probability (PACR) may be obtained by the processing module 21 and the calculation module 22.

In some examples, a Secure Authentication Efficiency (SAE) is calculated based on a secure authentication Probability (PSA), an authentication request transmission Probability (PART), and a covert authentication rejection Probability (PACR). The specified Security Authentication Efficiency (SAE) can be represented by the formula (11).

Additionally, in some examples, at an optimized energy allocation factor

And a signal-to-noise ratio threshold μ within a feasibility range, the Secret Authentication Efficiency (SAE) constrained by the authentication request transmission Probability (PART) and the covert authentication rejection Probability (PACR) gets a maximum. Specifically, the relationship of the maximum value of the Secret Authentication Efficiency (SAE), the transmission probability of the authentication request (PART), and the concealed authentication rejection Probability (PACR) is obtained by equation (12).

Fig. 8 is a schematic diagram showing a structure of a physical layer authentication device according to an example of the present disclosure. In some examples, both the transmitting end and the receiving end include an authentication device 30 as shown in fig. 8.

In some examples, as shown in fig. 8, authentication device 30 includes a processor 31 and a memory 32. The processor 31 and the memory 32 are connected to a communication bus, respectively. In some examples, memory 32 may be a high-speed RAM memory or a non-volatile memory. Those skilled in the art will appreciate that the configuration of the authentication device 30 shown in fig. 8 is not intended to limit the present disclosure, and may be a bus configuration, a star configuration, a combination of more or fewer components than those shown in fig. 8, or a different arrangement of components.

Wherein the processor 31 is a control center of the authentication device 30. In some examples, it may be a Central Processing Unit (CPU), and processor 31 connects various parts of the entire authentication device 30 using various interfaces and lines, by running or executing software programs and/or modules stored in memory 32, and calling program code stored in memory 32, for performing the following operations:

in the case of single-bit feedback of channel state information at the receiving end, the transmitting end transmits a marker signal to the wireless channel based on a single-bit concealment protocol in which the energy allocation factor of the information signal is kept fixed and at an optimized value for an interval period (performed by the authentication device 30 at the transmitting end), the marker signal including an authentication signal and an information signal.

A receiving end receives the marking signal, and processes the marking signal based on a single-bit concealment protocol to obtain the secret authentication probability; obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the signal-to-interference-and-noise ratio of the received information signal; and calculates a secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability, and the secret authentication rejection probability to determine a concealment level of physical layer authentication (performed by the authentication device 30 of the receiving end).

In some examples, the processor 31 of the authentication device 30 also performs the following operations: in the single-bit concealment protocol, the single-bit information of the signal-to-noise ratio threshold value mu is fed back to a transmitting end, and the setting is carried out

Let P

_ACR0, wherein R_bRepresenting the regular signal rate.

In some examples, the processor 31 of the authentication device 30 also performs the following operations: based on P_ACRThe optimum value of the energy allocation factor of the information signal is calculated by the following equation (10):

wherein the content of the first and second substances,

ε_ARTis the lower bound of the authentication request transmission probability, γ_bRepresenting the average signal-to-noise ratio, R_bRepresenting the regular signal rate.

In some examples, the processor 31 of the authentication device 30 also performs the following operations: the secret authentication efficiency is calculated by the following formula (11): eta is P_ART(1-P_ACR)P_SA(11) Wherein P is_ARTIndicating the probability of transmission of an authentication request, P_ACRDenotes the covert authentication rejection probability, P_SARepresenting a secret authentication probability.

In some examples, the processor 31 of the authentication device 30 also performs the following operations: the signal-to-interference-and-noise ratio of the information signal is calculated by the following formula (6):

wherein the content of the first and second substances,

represents an energy distribution factor of the information signal,

energy distribution factor representing authentication signal, tag signal block transmission, gamma_b,iRepresents the signal-to-noise ratio of the channel of the ith block mark signal at the receiving end, h_b,iIndicating the channel gain of the i-th block flag signal,

representing the noise variance at the receiving end.

In some examples, it should be understood that the disclosed apparatus may be implemented in other ways. For example, the above-described device examples are merely illustrative, and for example, the division of the units is only one logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of some interfaces, devices or units, and may be an electric or other form.

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.

In addition, in some examples, each functional unit may be integrated into one processing unit, each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

In some examples, 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 memory. Based on such understanding, the technical solution of the present disclosure may be embodied in the form of a software product, which is stored in a memory and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present disclosure. And the aforementioned memory comprises: a U-disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic or optical disk, and other various media capable of storing program codes.

In some examples, a computer-readable storage medium is disclosed, and it will be understood by those of ordinary skill in the art that all or part of the steps in the various physical layer authentication methods in the above examples can be implemented by a program (instructions) to instruct associated hardware, where the program (instructions) can be stored in a computer-readable memory (storage medium), where the memory can include: flash disks, Read-Only memories (ROMs), Random Access Memories (RAMs), magnetic or optical disks, and the like.

While the present disclosure has been described in detail in connection with the drawings and examples, it should be understood that the above description is not intended to limit the disclosure in any way. Those skilled in the art can make modifications and variations to the present disclosure as needed without departing from the true spirit and scope of the disclosure, which fall within the scope of the disclosure.

Claims

1. A physical layer authentication method based on single-bit concealment protocol is a concealment analysis method of physical layer authentication of a wireless communication system including a transmitting end and a receiving end,

the method comprises the following steps:

the transmitting end transmits a mark signal to a wireless channel based on a single-bit concealment protocol, wherein the mark signal comprises an authentication signal and an information signal, and in the single-bit concealment protocol, an energy distribution factor of the information signal is kept fixed and is an optimized value in an interval time period;

the receiving end receives the marking signal, and processes the marking signal based on the single-bit concealment protocol to obtain the secret authentication probability;

obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the received signal-to-interference-and-noise ratio of the marking signal; and is

Calculating a secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability, and the covert authentication rejection probability to determine a covert level of physical layer authentication,

wherein the secret authentication efficiency satisfies: eta is P_ART(1-P_ACR)P_SAWhere η represents the secret authentication efficiency, P_ARTRepresents the authentication request transmission probability and satisfies

P_ACRRepresents the covert authentication rejection probability and satisfies

P_SARepresents the secret authentication probability and satisfies P_SA＝max{P_D,1-P_D,20, mu represents a signal-to-noise ratio threshold, and the signal-to-interference-and-noise ratio of the marking signal satisfies:

wherein the content of the first and second substances,

an energy distribution factor representing the information signal,

an energy distribution factor representing the authentication signal, the signature signal being sent in blocks, gamma_b,iRepresenting the signal-to-noise ratio, h, of the i-th block of the mark signal at the receiving end_b,iIndicating the channel gain of the i-th block flag signal,

representing the noise variance, R, of the receiving end_bRepresenting the conventional signal rate, P_D,1Indicating the detection rate, P, of a legitimate receiver_D,2Indicating the detection rate of an illegal receiving end, in the single-bit concealment protocol, setting

Let P_ACR0, based on P_ACR0, the optimized value of the energy allocation factor of the information signal satisfies:

wherein the content of the first and second substances,

ε_ARTis the lower bound of the authentication request transmission probability, γ_bRepresenting the average signal-to-noise ratio.

2. A physical layer authentication system based on a single-bit covert protocol,

the method comprises the following steps:

a transmitting device which transmits a marker signal to a wireless channel based on a single-bit concealment protocol, the marker signal including an authentication signal and an information signal, in the single-bit concealment protocol, an energy allocation factor of the information signal is kept fixed and an optimized value in an interval period;

a receiving device, comprising: the processing module receives the marking signal, processes the marking signal based on the single-bit concealment protocol and obtains the secret authentication probability; a calculation module for obtaining an authentication request transmission probability and a concealed authentication rejection probability based on the received signal-to-interference-and-noise ratio of the marker signal; and a decision module for calculating a secret authentication efficiency based on the secret authentication probability, the authentication request transmission probability and the probability of the secret authentication rejection to determine a concealment level of physical layer authentication,

P_ACRRepresents the covert authentication rejection probability and satisfies

wherein the content of the first and second substances,

an energy distribution factor representing the information signal,

an energy distribution factor representing the authentication signal, the signature signal being sent in blocks, gamma_b,iIs shown asSignal-to-noise ratio of i block mark signal in said receiving device, h_b,iIndicating the channel gain of the i-th block flag signal,

representing the noise variance, R, of said receiving means_bRepresenting the conventional signal rate, P_D,1Indicating the detection rate, P, of a legitimate receiver_D,2Indicating the detection rate of an illegal receiving device, in which single-bit concealment protocol is set

wherein the content of the first and second substances,