Data encryption transmission method, decryption method, communication equipment and storage medium

Abstract

The invention relates to the technical field of wireless communication, and discloses a data encryption transmission method, a decryption method, communication equipment and a storage medium. The method comprises the following steps: encrypting original channel data by using a target security key to obtain ciphertext channel data; performing random beam forming processing on the ciphertext channel data to obtain target channel data with artificial noise; wherein the artificial noise is determined based on a target angle between the base station and the target equipment, and a target security key is stored in the target equipment; sending the target channel data to a target device at the target angle, so that the target device decrypts the target channel data by using the target security key; wherein no artificial noise exists on the target equipment. Therefore, through a dual encryption method, the eavesdropping success rate is remarkably reduced, and the data confidentiality and the anti-attack capability of a wireless link are effectively improved.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and in particular to a data encryption transmission method, decryption method, communication device, and storage medium. Background Technology

[0002] In 5G and future mobile communication systems, with the increase in transmission speed and the expansion of service scenarios, the openness of wireless communication makes signals easily intercepted and analyzed by eavesdroppers during propagation in space. The confidentiality and integrity of communication content face severe challenges, thus making the need for physical layer secure transmission technology increasingly urgent. However, existing wireless transmission technologies still have certain limitations, necessitating improvements in the comprehensiveness of their security protection and their anti-interference capabilities. Summary of the Invention

[0003] This application aims to at least partially solve one of the technical problems in related technologies. To this end, this application proposes a data encryption transmission method, a decryption method, a communication device, and a storage medium. The main technical solutions adopted in this application include:

[0004] In a first aspect, embodiments of this application provide a data encryption transmission method applied to a base station. The method includes: encrypting original channel data using a target security key to obtain ciphertext channel data; performing random beamforming processing on the ciphertext channel data to obtain target channel data with artificial noise; wherein the artificial noise is determined based on the target angle between the base station and the target device, and the target device stores the target security key; and sending the target channel data to the target device at the target angle so that the target device can decrypt the target channel data using the target security key; wherein there is no artificial noise on the target device.

[0005] Optionally, random beamforming is performed on the encrypted channel data to obtain target channel data with artificial noise, including: random beamforming is performed on the encrypted channel data using a signal shaping factor and a noise shaping factor to obtain the target channel data; wherein the signal shaping factor and the noise shaping factor are determined based on the channel sounding reference signal of the target device.

[0006] Optionally, the signal shaping factor is determined by: performing channel estimation based on the channel sounding reference signal to obtain channel estimation parameters; performing direction of arrival estimation based on the channel estimation parameters to obtain the target angle where the target device is located; and generating the signal shaping factor based on the target angle.

[0007] Optionally, the noise shaping factor is determined as follows: channel estimation is performed based on the channel sounding reference signal to obtain channel estimation parameters; direction of arrival estimation is performed based on the channel estimation parameters to obtain the target angle where the target device is located; multiple candidate noise angles are selected within a preset angle range based on the target angle, and the noise shaping vector corresponding to each candidate noise angle is determined; projection calculation is performed on the target angle based on the noise shaping vector corresponding to each candidate noise angle to obtain the synthetic beam energy at the target angle; when the synthetic beam energy reaches a preset energy threshold, the noise shaping factor is determined using the noise shaping vector corresponding to each candidate noise angle.

[0008] Optionally, the target security key is determined by the following methods: determining the current security key sequence number based on a preset negotiation rule; determining the target security key sequence number using the current security key sequence number and a preset offset; and searching the security key set using the target security key sequence number to obtain the target security key.

[0009] Optionally, the security key set is determined by: performing uplink channel estimation based on the uplink pilot sequence of the target device to obtain the channel response matrix of the target device; generating a quantization sequence based on the channel response matrix; and using the quantization sequence to generate the security key set.

[0010] Optionally, the target security key has a target security key sequence number; encrypting the original channel data using the target security key to obtain ciphertext channel data includes: encrypting the original channel data using the target security key to obtain ciphertext channel data; wherein the ciphertext channel data carries the target security key sequence number.

[0011] Secondly, embodiments of this application provide a data decryption method applied to a target device. The target device is located at a target orientation of a base station, the target orientation corresponds to a target angle, the target device stores a target security key, and the base station stores a set of security keys. The method includes: receiving target channel data sent by the base station; wherein the target channel data is accompanied by artificial noise determined based on the target angle, and there is no artificial noise on the target device; the target channel data is obtained by performing random beamforming processing on ciphertext channel data, and the ciphertext channel data is obtained by encrypting the original channel data using the target security key in the set of security keys; and decrypting the target channel data using the target security key.

[0012] Thirdly, embodiments of this application provide a data encryption transmission device applied to a base station. The device includes: a key encryption module for encrypting original channel data using a target security key to obtain ciphertext channel data; a beamforming module for performing random beamforming processing on the ciphertext channel data to obtain target channel data with artificial noise; wherein the artificial noise is determined based on the target angle between the base station and the target device, and the target device stores the target security key; and a data transmission module for sending the target channel data to the target device at the target angle, so that the target device can decrypt the target channel data using the target security key; wherein there is no artificial noise on the target device.

[0013] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of any of the methods described above.

[0014] Fifthly, this application also provides a communication device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of any of the above methods.

[0015] Sixthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of any of the methods described above.

[0016] In the above embodiments, the original channel data is first encrypted using the target security key to obtain ciphertext channel data. Then, artificial noise is superimposed on the ciphertext channel data for random beamforming processing. Through this dual encryption method, the base station can overwhelm eavesdroppers from other directions with noise. Simultaneously, since there is no artificial noise in the direction of the target device, the target device can decrypt losslessly within the target angle using the known key, thereby significantly reducing the success rate of eavesdropping and improving the data confidentiality and anti-attack capability of the wireless link. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a data encryption transmission method according to an embodiment of this application;

[0019] Figure 2a This is a flowchart of a method for determining a signal shaping factor according to an embodiment of this application;

[0020] Figure 2b This is a schematic diagram of an 8-antenna uniform linear array according to an embodiment of this application;

[0021] Figure 3 This is a flowchart of a data decryption method provided according to an embodiment of this application;

[0022] Figure 4 This is a structural block diagram of a data encryption transmission device according to an embodiment of this application;

[0023] Figure 5 This is an internal structural diagram of a communication device provided according to an embodiment of this application. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] In 5G and future mobile communication systems, with the increase in transmission speed and the expansion of business scenarios, the openness of wireless communication makes it easy for eavesdroppers to intercept and analyze signals when they propagate in space. The confidentiality and integrity of communication content face severe challenges, so the demand for physical layer secure transmission technology is becoming increasingly urgent.

[0026] Encryption methods in related technologies include base stations using large-scale antenna arrays to search the angle spectrum of the channel estimation of the target terminal's Sounding Reference Signal (SRS), calculate the null angle, and add interference beam noise to the downlink Physical Downlink Shared Channel (PDSCH) signal based on uplink and downlink channel reciprocity. The interference beam noise does not affect the demodulation of the useful signal position of the target terminal, but affects the demodulation of the useful signal at other positions. This secure transmission method enhances the downlink anti-eavesdropping capability.

[0027] Furthermore, wireless multipath channels possess spatial uniqueness, rapid time-varying characteristics, and unpredictability. During communication, based on pilot signals between the communicating parties, a consistent encrypted data stream is generated in real-time at both the base station and terminal sides, using the wireless channel as the source. The transmitting end uses this encrypted data stream to encrypt the transmitted data, and the receiving end decrypts the received data. This encryption and decryption process achieves physical layer encryption of information. Since the channel changes over time and the key is automatically updated, this update is unpredictable for eavesdroppers. Simultaneously, when the distance between the eavesdropper and the legitimate receiver exceeds orders of magnitude of the wavelength, the wireless channel characteristics become irrelevant. However, if the eavesdropper and the legitimate user are relatively close, the wireless channel characteristics are easily acquired, making it difficult to guarantee system security.

[0028] Understandably, anti-eavesdropping techniques based on precoding and artificial noise do not affect the demodulation of useful signals at the target terminal's location, but do affect the demodulation of useful signals at other locations. This secure transmission method enhances downlink anti-eavesdropping capabilities but is not suitable for uplink communication, thus its security performance is limited. Key-based secure transmission technologies can encrypt both uplink and downlink communication, but if the eavesdropper and the legitimate user are close together, the wireless channel characteristics are easily obtained, making it difficult to guarantee system security. Therefore, related wireless transmission technologies still have room for improvement in terms of comprehensive security protection and anti-interference capabilities. There is an urgent need for a transmission technology that can overcome the above limitations, enhance uplink and downlink security, and effectively resist close-range eavesdropping.

[0029] Based on this, according to the embodiments of this application, an embodiment of a data encryption transmission method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0030] This embodiment provides a method for encrypted data transmission. Figure 1 This is a flowchart of a data encryption transmission method according to an embodiment of this application, such as... Figure 1 As shown, the process includes the following steps:

[0031] S110. Encrypt the original channel data using the target security key to obtain ciphertext channel data.

[0032] It should be noted that the target security key needs to be determined first from the security key set.

[0033] The security key set can refer to a collection of multiple valid security keys that are pre-negotiated or dynamically generated between the base station and the target device. For example, the security key set may store security keys used for data encryption and security key serial numbers used to index the security keys. Furthermore, since the channel characteristics of the wireless channel change over time, the security key set is updated at the same frequency on both the base station and the target device sides.

[0034] It should be noted that the target device refers to a legitimate terminal device that interacts with the base station in a wireless communication scenario, capable of receiving encrypted data sent by the base station and sending uplink information to the base station. For example, the target device can refer to a specific communication entity such as a mobile phone, an IoT sensor, or a smart terminal.

[0035] The target security key is a key selected from the security key set during a single or short period of communication to encrypt the data transmitted in this communication. It is strongly associated with the context of the current communication, known only to the base station and the target device, and is uniquely valid in a single or short period of communication, ensuring the specificity and security of the encryption process.

[0036] Specifically, the core logic for determining the target security key in the security key set is: based on the real-time communication context between the base station and the target device, a unique and synchronized key is selected from the key set according to the rules agreed upon by both parties, ensuring that eavesdroppers cannot predict or obtain it.

[0037] For example, the set of security keys can be determined in the following ways.

[0038] First, uplink channel estimation is required based on the uplink pilot sequence of the target device to obtain the channel response matrix of the target device.

[0039] The channel response matrix, in particular, describes the influence of the channel on various dimensions of the signal during its propagation from the transmitter to the receiver in wireless communication. Its elements reflect characteristics such as signal attenuation, phase shift, and time delay along different transmission-to-receiver paths.

[0040] It's important to note that a communication connection needs to be established before data transmission. This can begin with the base station and the target device exchanging pilot sequences. Specifically, taking one side as an example, the target device sends a known uplink pilot sequence to the base station for identification and extraction. The base station then receives the pilot sequence after it has passed through the channel. At this point, the received sequence has been affected by channel attenuation or noise, resulting in differences from the original pilot sequence. Next, the base station compares the known original pilot sequence with the received pilot sequence, using estimation algorithms such as least squares or least mean square error to infer the channel's influence on the pilot sequence. Finally, based on the estimation algorithm's results, the channel's influence on each dimension of the signal is represented in matrix form to obtain the channel response matrix.

[0041] Optionally, after calculating the target device's channel response matrix at the base station, the same calculation process can be repeated. That is, the base station sends the known downlink pilot sequence to the target device so that the target device can perform calculations to obtain the base station's channel response matrix.

[0042] Furthermore, a quantization sequence is generated based on the channel response matrix, and a secure key set is generated using the quantization sequence.

[0043] In this context, a quantization sequence refers to a matrix sequence formed by converting continuous channel characteristic data into discrete binary symbols according to preset rules. Through quantization operations, continuous physical characteristics of the channel, such as attenuation or phase, can be transformed into discrete digital sequences that can be used for subsequent key generation and encryption processes.

[0044] For example, A channel estimation data points can be extracted from the channel response matrix. These A data points are then divided into B groups, and the overall average of all A data points and the group average of each group within the B groups are calculated. If the group average of a data point is greater than the overall average, the group is coded as 1; otherwise, it is coded as 0. This results in a B-bit binary sequence, which is the quantization sequence. Similarly, not only can the base station determine its quantization sequence using the above method, but the target device can also determine its quantization sequence using the same method.

[0045] After determining the quantization sequence, key negotiation is performed first. Specifically, the base station can generate random numbers and calculate Cyclic Redundancy Check (CRC). The base station then scrambles the random numbers using the quantization sequence and sends them to the target device in conjunction with the CRC check. The target device descrambles the random numbers using its own generated quantization sequence of the same length and verifies the CRC. If the CRC verification passes, meaning both parties confirm the consistency of the quantization sequences, the key negotiation is successful. After successful negotiation, multiple keys can be generated based on the quantization sequence through hashing or expansion operations. These multiple keys are then integrated into a secure key set, completing the construction of a key set based on the channel response matrix and the quantization sequence.

[0046] Thus, by leveraging the randomness and reciprocity of the wireless channel itself to extract the shared key, a high-strength and dynamically updatable security key set can be established between the base station and the target device without the need for pre-installed certificates or additional hardware, significantly improving the anti-eavesdropping capability and deployment flexibility of the communication system.

[0047] Furthermore, after constructing the security key set, the target security key can be determined from it. For example, the current security key sequence number can first be determined based on a preset negotiation rule. Then, the target security key sequence number is determined using the current security key sequence number and a preset offset. Finally, the target security key is obtained by searching the security key set using the target security key sequence number.

[0048] The preset negotiation rule can refer to the specific algorithm or logic agreed upon in advance by the base station and the target device for calculating the current security key sequence number. For example, the preset negotiation rule could be polling based on the number of communications, such as incrementing the current security key sequence number by 1 after each channel data transmission between the base station and the target device, and then cyclically using keys from the key set. Alternatively, it could be based on a time period switching, such as setting a fixed time interval to update the current security key sequence number at the designated time, thereby selecting the corresponding key periodically. The current security key sequence number can refer to the number corresponding to the security key currently in use or awaiting verification, calculated according to the preset negotiation rule within the security key set; it can be understood as the starting reference value for determining the target security key sequence number. The preset offset is a fixed or dynamically adjusted value agreed upon in advance by the base station and the target device, used to offset and adjust the current security key sequence number to enhance the randomness and security of key selection.

[0049] Specifically, the base station and target device sides can be designed with key storage buffers. Before transmitting data, the key buffer is initialized to 0. After key negotiation, the latest generated current security key is stored sequentially, using its current security key sequence number as its index. That is, the key storage buffer can store a total of K sets of security keys, with their sequence numbers 0, 1, 2, ..., K-1. Optionally, when the data storage capacity of the key storage buffer reaches its limit, it can restart storing from the beginning, sequence number 0, to overwrite the oldest security key.

[0050] To prevent encryption / decryption failures due to key asymmetry caused by either the base station or the target device failing to update the key in a timely manner, the determination of the target security key can be designed as a boundary protection problem. That is, during each encryption operation, the current security key sequence number and its corresponding current security key are first retrieved from the key storage buffer. If the current security key sequence number is denoted as k, the target security key sequence number can be determined using the following formula:

[0051] k′=(k+15)%K

[0052] In the formula, k′ represents the target security key sequence number; k represents the current security key sequence number; and K represents the total number of key data stored in the key storage buffer.

[0053] Thus, by introducing a protection boundary mechanism that modulo the current sequence number and offset within the key set, the base station and the target device can synchronously and reliably lock the same target security key. Even if there are differences in key update timing, it can automatically roll back to the valid key, avoiding encryption and decryption synchronization issues and significantly improving the continuous security and robustness of wireless communication.

[0054] Raw channel data refers to the unencrypted downlink channel data transmitted by the base station to the target device in wireless communication. This includes core content that needs to be protected by encryption, such as raw information like voice, video, or control commands.

[0055] Ciphertext channel data refers to encrypted data generated after the original channel data has been encrypted using a target security key. This encrypted data cannot be directly deciphered. It transforms the original data using an encryption algorithm, and only the receiver possessing the corresponding target security key can decrypt it and restore it to the original channel data, thus ensuring the security of data transmission.

[0056] Specifically, since the target security key has a target security key sequence number, encrypting the original channel data using the target security key to obtain ciphertext channel data can include: encrypting the original channel data using the target security key to obtain ciphertext channel data.

[0057] It is important to emphasize that the encrypted channel data carries the target security key sequence number. Specifically, the original channel data can first be encrypted using the target security key to obtain encrypted channel data. Then, the target security key sequence number is appended to the encrypted channel data to obtain the encrypted channel data.

[0058] The encrypted channel data can refer to the intermediate encrypted data generated after the original channel data is directly encrypted using the target security key.

[0059] Specifically, the base station can invoke a preset encryption algorithm, using the target security key as the encryption key, to directly encrypt the original channel data, thereby obtaining encrypted channel data. The base station can then incorporate the target security key sequence number into the encrypted channel data in a preset manner. For example, appending can be a preset method, that is, directly concatenating the binary data of the target security key sequence number to the end of the encrypted channel data. This concatenated sequence is the ciphertext channel data.

[0060] It should be noted that for the uplink, the uplink channel data from the target device side (as the sender) can be used as the original channel data and double-encrypted using the same processing method.

[0061] Thus, by employing a dual encryption strategy, the encrypted channel data is simultaneously kept highly confidential by both the target security key and the target security key sequence number, thereby achieving end-to-end integrity and confidentiality enhancement in both uplink and downlink, significantly improving the security level of wireless channel data.

[0062] S120. Perform random beamforming processing on the encrypted channel data to obtain target channel data with artificial noise.

[0063] It needs to be emphasized again that key storage buffers can be designed on both the base station and the target device side, that is, security key sets are stored on both the base station side and the target device side, from which the target security key can be extracted.

[0064] Artificial noise refers to interference signals actively generated and transmitted by a base station in directions other than the target device to enhance communication security. Specifically, artificial noise is determined based on the target angle between the base station and the target device. That is, artificial noise is designed based on the target angle between the base station and the target device to ensure that the energy is zero in the direction of the target device, so as not to affect its reception, while forming interference in other directions to reduce the eavesdropper's ability to decipher ciphertext.

[0065] Specifically, random beamforming is performed on the encrypted channel data to obtain target channel data with artificial noise. The target channel data can be obtained by using signal shaping factor and noise shaping factor to perform random beamforming on the encrypted channel data.

[0066] The signal shaping factor can refer to vector data focused on the direction of the target device, used to enhance the signal energy from the base station to the target device. The noise shaping factor can refer to vector data pointed in the direction of a potential eavesdropper, used to apply artificial noise in that direction. Specifically, the signal shaping factor and the noise shaping factor can be determined based on the channel sounding reference signal of the target device. For example, the base station can first receive the channel sounding reference signal transmitted by the target device from the target angle, and then estimate the downlink channel characteristics using the uplink and downlink channel dissimilarity, thereby further determining the signal shaping factor that can enhance the signal and the noise shaping factor that can increase interference.

[0067] Furthermore, after determining the signal beamforming factor and noise beamforming factor at the location of the target device, the encrypted channel data is first modulated to obtain encrypted symbol data. This encrypted symbol data is then combined with the signal beamforming factor, and a signal component is generated through vector transpose multiplication. Next, a random number is selected and combined with the noise beamforming factor, and the noise component is obtained through vector transpose multiplication as well. Finally, the signal component and the noise component are superimposed to complete the random beamforming process, resulting in the final target channel data transmitted by the base station.

[0068] For example, assuming there is a target device (UE) and an eavesdropping device in the environment, then based on the principles of digital signals, the signals received by both from the base station can be expressed as follows:

[0069] y UE =h1·x T +n

[0070] y Eave =h2·x T +n

[0071] In the formula, x represents the target channel data transmitted by the base station, and the superscript T indicates transpose; y UE h1 represents the signal received by the target device UE; h1 represents the downlink channel between the base station and the target device UE, which is a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; y Eave h1 represents the signal received by the eavesing device; h2 represents the downlink channel between the base station and the eavesing device, which is also a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; and n represents the background noise.

[0072] It should be noted that the target channel data x is also a 1×N vector. Specifically, the expression for the target channel data can be shown below:

[0073]

[0074] In the formula, x represents the target channel data transmitted by the base station, which is a 1×N vector, and the superscript T indicates transpose; P s represents the signal shaping factor, a 1×N vector, with the superscript T indicating transpose; u represents the ciphertext symbol data sent by the base station to the target device UE, which is obtained by modulating the ciphertext channel data; P n The noise shaping factor is a 1×N vector, with the superscript T indicating transpose; r represents a random number.

[0075] Understandably, since the noise shaping factor is a vector data pointing in the direction of a potential eavesdropper, and it is designed to be orthogonal to the channel at the target angle where the target device (UE) is located, the noise components generated by the noise shaping factor can effectively interfere with the eavesdropping device without interfering with the target device (UE). It should be noted that this situation, where there is no interference in the direction of the target device (UE), can be called an energy formation null trap.

[0076] Furthermore, we have:

[0077]

[0078] In the formula, h1 represents the noise component of the base station signal received by the target device (UE); h1 represents the downlink channel between the base station and the target device (UE), which is a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; P n The noise shaping factor is a 1×N vector, with the superscript T indicating transpose; r represents a random number. h1 represents the noise component of the base station signal received by the eavesing device; h2 represents the downlink channel between the base station and the eavesing device, which is also a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; w represents artificial noise, and the superscript T indicates transpose.

[0079] Therefore, the signals received by the target device (UE) and the eavesdropping device from the base station can be expressed as follows:

[0080] y UE =h1·P s T u+n

[0081]

[0082] In the formula, y UE h1 represents the signal received by the target device UE; h1 represents the downlink channel between the base station and the target device UE, which is a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; P srepresents the signal shaping factor, a 1×N vector, with the superscript T indicating transpose; u represents the ciphertext symbol data sent by the base station to the target device UE, which is obtained by modulating the ciphertext channel data; y Eave h1 represents the signal received by the eavesing device; h2 represents the downlink channel between the base station and the eavesing device, which is also a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; n represents the background noise; w represents artificial noise, and the superscript T indicates transpose.

[0083] As can be seen from the above formula, since the noise shaping factor forms a null energy on the target device (UE), the artificial noise component has no effect on the signal actually received by the UE; it only contains the valid ciphertext signal and background noise, making it clear and decryptable. However, the signal received by the eavesdropping device contains both valid signal and strong artificial noise, making it difficult to decrypt.

[0084] Thus, by superimposing random artificial noise with a noise shaping factor orthogonal to the target device's channel, the base station forms an energy null trap in the target direction, ensuring that legitimate users receive only valid ciphertext signals with a high signal-to-noise ratio, while potential eavesdroppers are overwhelmed by strong artificial noise. This achieves spatially selective secure transmission with extremely low implementation complexity, significantly improving the system's anti-eavesdropping capability.

[0085] S130. Send the target channel data to the target device at the target angle so that the target device can decrypt the target channel data using the target security key.

[0086] It is important to reiterate that because the noise shaping factor forms a null on the target device, meaning there is no artificial noise on the target device, the artificial noise is transparent to the target device and will not interfere with its signal. Therefore, after the target channel data is sent to the target device at the target angle, the target device first receives the target channel data sent by the base station at the target angle. At this time, the received signal contains useful signal components and background noise, but the artificial noise has been canceled out by the null. Subsequently, to eliminate the effects of channel attenuation, phase shift, etc., the target device can use the DMRS (Demodulation Reference Signal) sequence to complete channel estimation and equalization.

[0087] For example, since the DMRS pilot sequence is a reference signal known to both the base station and the target device, the target device can first extract the DMRS pilot sequence from the received signal and use the least squares method to calculate the channel characteristics of the pilot subcarrier positions, such as channel gain or phase, to obtain the channel state information (CSI) at the pilot positions. For non-pilot subcarrier positions, the complete CSI of the data subcarriers within the full bandwidth can be obtained by linearly extrapolating from the CSI of adjacent pilots and using the nearest neighbor interpolation method, thereby understanding the overall impact of the channel on the signal. Subsequently, the target device can use the CSI obtained from channel estimation to design an equalizer using the minimum mean square error algorithm to perform reverse compensation on the received target channel data, such as canceling attenuation and correcting phase offset. After final equalization, the encrypted channel signal transmitted by the base station can be successfully recovered.

[0088] Understandably, for eavesdropping devices, the information they receive is encrypted data mixed with random noise, making it impossible for them to recover the encrypted channel signal through channel estimation like the target device. Furthermore, since the eavesdropping device cannot obtain the double-encrypted target security key, it is even more unable to correctly recover the true information transmitted by the base station.

[0089] In the above implementation, the original channel data is first encrypted using the target security key to obtain ciphertext channel data. Then, directional artificial noise is superimposed on the ciphertext channel data for random beamforming processing. This dual encryption method allows the base station to overwhelm eavesdroppers from other directions with noise. Simultaneously, since there is no artificial noise in the direction of the target device, the target device can decrypt the data losslessly within the target angle using the known key, thus significantly reducing the success rate of eavesdropping and improving the data confidentiality and anti-attack capability of the wireless link.

[0090] In some implementation methods, please refer to Figure 2a The signal shaping factor is determined in the following way:

[0091] S210. Channel estimation is performed based on the channel sounding reference signal to obtain the channel estimation parameters.

[0092] Channel Sounding Reference Signal (CSRS) refers to a known sequence of signals transmitted by a base station or target device to enable the other party to perceive the characteristics of the wireless channel. It is important to emphasize that the CSRS is a standardized structured sequence known to both communicating parties, similar to a fixed test code.

[0093] Channel estimation parameters refer to a set of parameters estimated based on channel sounding reference signals, usually represented in the form of vectors or matrices. They are used to describe channel phase or amplitude differences. It should be noted that due to the different target angles of the target device, the path differences of the signals sent by it to each base station antenna are different, resulting in phase or amplitude differences. Therefore, the channel estimation parameters can be in the form of a 1×N complex vector, where N is the number of base station antennas.

[0094] Exemplarily, the transmitting end (which can be the target device) sends known channel sounding reference signals to the receiving end (which can be the base station), and the receiving end can receive the signals. Since the receiving end knows the original sequence of the channel sounding reference signals sent by the transmitting end, it can use the correspondence between the received signals and the known original sequence, and calculate the influence of the communication channel on the signals through channel estimation algorithms, so as to obtain a vector that quantitatively describes the channel characteristics between the transmitting end and the receiving end, that is, the channel estimation parameters are obtained.

[0095] S220. Perform direction-of-arrival estimation based on the channel estimation parameters to obtain the target angle where the target device is located.

[0096] Among them, direction-of-arrival estimation (DOA estimation) refers to a technique that uses the signals received by the base station antenna array to calculate the spatial azimuth angle of the target device relative to the base station. Its core is to analyze the phase difference and amplitude difference of the signals received by multiple antennas, and inversely deduce the direction of the signals to achieve spatial positioning of the target device's position.

[0097] Exemplarily, please refer to Figure 2b , assuming that in the current environment, the number of target devices M = 1, that is, there is only one target device, and the base station receiving array uses an N = 8 antenna uniform linear array (the black dots in the figure represent antennas), and M < N. In addition, the interval between adjacent antenna elements is d = 0.54λ (λ is the wavelength). θ represents the direction of the incoming wave in the plane. If the base station needs to inversely deduce the target angle where the target device is located, then first, it needs to calculate its covariance matrix R based on the channel estimation parameter H SRS Subsequently, based on matrix theory knowledge, perform eigenvalue decomposition on the covariance matrix R of the channel estimation parameters to obtain the signal subspace E s and the noise subspace E n . Among them, the signal subspace E s can be understood as the channel of the useful signal, containing the main energy and direction information of the target device signal, while the noise subspace E n can be understood as the channel of the useless noise, mainly environmental noise and interference energy.

[0098] Next, an array signal processing algorithm is used to calculate the spectral function to estimate the direction of arrival. For example, Multiple Signal Classification (MUSIC) can be employed, which utilizes the orthogonality between the signal direction vector and the noise subspace to scan the spatial spectrum at different angles. Since the energy of the signal subspace is concentrated at the target angle where the target device is located, a sharp peak will appear in the spectral function when MUSIC scans the target angle θ0 of the target device. By then examining the angle corresponding to this peak, the target angle of the target device can be obtained.

[0099] S230, Generate signal shaping factor based on target angle.

[0100] Specifically, firstly, based on the target angle θ0, the ideal response vector of the base station antenna array at that angle is calculated. This vector describes the phase and amplitude relationship of the signal that should be received by each antenna if the signal arrives at the target angle θ0. Subsequently, the signal shaping factor is designed as a weighted vector that matches the array response vector at the target angle θ0, ensuring that the transmitted signals of each antenna of the base station are in phase and superimposed in the direction of the target angle, thus forming a concentrated beam energy.

[0101] For example, taking a uniform linear array with N=8 antennas as an example, the generation formula can be shown as follows:

[0102] In the formula, N is the number of base station antennas; j is the imaginary unit; d is the antenna spacing; θ0 is the target angle where the target device is located; and λ is the signal wavelength.

[0103] This formula is essentially a phase-weighted vector for an 8-antenna uniform linear array. Its goal is to concentrate signal energy at the target angle θ0 where the target device is located, while attenuating it in other directions. sin(π*θ0 / 180) represents the sinusoidal processing of the angle, the core of which is mapping the angle information onto the spatial phase difference of the antenna array. Each element in the matrix is ​​a phase rotation factor, corresponding to the Nth antenna.

[0104] It should be noted that when (n=1) e 0 That is, the first antenna has no additional phase rotation.

[0105] Specifically, 2πd / λsin(π*θ0 / 180) represents the phase difference between adjacent antennas. When a signal is incident from the θ0 direction, the signals received by adjacent antennas will have a phase difference due to the path difference. This phase difference is determined by the antenna spacing d, the signal wavelength λ, and the azimuth angle θ0, and is essentially a manifestation of spatial geometry in phase. N-1 represents the antenna number offset (N ranges from 1 to 8), indicating the difference in number between the Nth antenna and the 1st antenna. Combining the previous phase difference, the total phase offset of the Nth antenna can be calculated, which is N-1 times the phase difference between adjacent antennas. Finally, by setting different phases for antennas with different numbers, the signals from all antennas are superimposed in phase in the θ0 direction, thus enhancing the signal, and canceling out of phase in other directions, thus weakening interference. Ultimately, a beam pointing towards θ0 is formed, resulting in a signal shaping factor P that matches the target angle. s .

[0106] In the above implementation, the channel is accurately estimated and a high-resolution DOA is obtained by using the channel sounding reference signal. Then, the target angle is mapped into a phase weighted vector that is superimposed in phase. The base station can form a high-gain, low-sidelobe directional beam in the direction of the target device, which not only significantly enhances the signal quality of the legitimate link, but also effectively suppresses interference and eavesdropping risks in other directions.

[0107] In some implementations, the noise shaping factor is determined as follows: First, channel estimation is performed based on the channel sounding reference signal to obtain channel estimation parameters. Then, direction of arrival estimation is performed based on the channel estimation parameters to obtain the target angle where the target device is located. Next, multiple candidate noise angles are selected within a preset angle range based on the target angle, and a noise shaping vector corresponding to each candidate noise angle is determined. Then, projection calculation is performed on the target angle based on the noise shaping vector corresponding to each candidate noise angle to obtain the synthetic beam energy at the target angle. Finally, when the synthetic beam energy reaches a preset energy threshold, the noise shaping factor is determined using the noise shaping vector corresponding to each candidate noise angle.

[0108] Understandably, calculating the noise shaping factor also requires channel estimation and direction of arrival estimation to obtain the target angle of the target device. However, the difference is that after determining the target angle of the target device, it is necessary to select multiple candidate noise angles within a preset angle range based on the target angle, and determine the noise shaping vector corresponding to each candidate noise angle.

[0109] The preset angle range can refer to a spatial angle interval that the base station has pre-defined as a possible location for eavesdroppers. For example, the target angle range [-65°, 65°] can be used as the preset angle range for selecting candidate noise angles. Candidate noise angles can refer to specific angles selected from the preset angle range for generating artificial noise beams. It should be noted that these angles are the directional transmission directions of the artificial noise and must avoid the target angle of the target device. Specifically, to ensure optimal interference effect, the spatial spectrum function of the MUSIC algorithm can be used to filter out zeros with lower energy in the spatial spectrum, denoted as θ1, θ2, ..., θ L There are L angles. These angles represent potential locations where eavesdroppers might be present, and the energy concentration of noise is optimal in these directions.

[0110] For each candidate noise angle θ L The corresponding noise shaping vector is generated based on the steering vector formula of a uniform linear array. For example, with an 8-antenna configuration, the noise shaping vector corresponding to the candidate noise angle is: ......

[0112]

[0113] In the formula, N is the number of base station antennas; j is the imaginary unit; d is the antenna spacing; θ1, θ2, ..., θ L λ represents the candidate noise angle; λ represents the signal wavelength.

[0114] Subsequently, a steering vector corresponding to the target angle θ0 is generated, whose form is consistent with the noise shaping vector, except that the angle is the target angle θ0. Furthermore, a noise shaping vector P is generated for each candidate noise angle. nL The projection of the guide vector corresponding to the target angle θ0 is calculated, and the square of the modulus is taken as the composite beam energy. The composite beam energy can be the energy projection value of the noise shaping vector at the target angle of the target device, calculated as the inner product of the noise shaping vector and the guide vector in the θ0 direction. Its magnitude reflects the interference intensity of artificial noise at the target angle; an ideal value is 0, i.e., a null trap is desired.

[0115] Further, it is determined whether the synthesized beam energy of each candidate noise angle is less than or equal to a preset energy threshold. If so, it indicates that the noise shaping vector forms a null in the target angle θ0 direction of the target device, i.e., it does not interfere with the target device. The preset energy threshold can be a critical energy value pre-agreed between the base station and the target device to determine whether the noise shaping vector forms a null in the target angle. For example, it can be a very small value close to 0, such as 10. -6Finally, all noise shaping vectors that meet the conditions are concatenated column-wise to form the final noise shaping factor P. n It is in the form of an N×L matrix, where N is the number of antennas and L is the number of candidate noise angles.

[0116] In the above implementation, by forming a deep null in the direction of the legitimate user, the interference to potential eavesdroppers is maximized without affecting the reception quality of the target device, thereby significantly improving the spatial security capacity and anti-interception capability of the system.

[0117] This specification also provides a data decryption method applied to a target device located at a target position relative to a base station. The target position corresponds to a target angle. The target device stores a target security key, and the base station stores a set of security keys. Please refer to... Figure 3 The method includes:

[0118] S310, Receive target channel data sent by the base station.

[0119] The target channel data includes artificial noise determined based on the target angle, but this artificial noise is not present on the target device; in other words, it is transparent to the target device. The target channel data is obtained by performing random beamforming processing on the ciphertext channel data, and the ciphertext channel data is obtained by encrypting the original channel data using the target security key from the security key set.

[0120] Specifically, when the target device is at the target location of the base station, it receives the target channel data sent by the base station. At this time, the target channel data can be represented as:

[0121] y UE =h1·P s T u+n

[0122] In the formula, y UE h1 represents the signal received by the target device; h1 represents the downlink channel between the base station and the target device, which is a 1×N vector, where N represents the number of antennas in the base station's receiving antenna array; P s denoted by the signal shaping factor, which is a 1×N vector, with the superscript T indicating transpose; u represents the ciphertext symbol data sent by the base station to the target device, which is obtained by modulating the ciphertext channel data; n represents the background noise.

[0123] Because the noise shaping factor forms a null on the target device, artificial noise is transparent to the target device and will not interfere with its signal. Therefore, after the target channel data is sent to the target device at the target angle, the target device first receives the target channel data sent by the base station at the target angle. At this time, the received signal contains useful signal components and background noise, but the artificial noise has been canceled by the null. Subsequently, in order to eliminate the effects of channel attenuation, phase shift, etc., the target device can use the DMRS sequence to complete channel estimation and equalization.

[0124] For example, since the DMRS pilot sequence is a reference signal known to both the base station and the target device, the target device can first extract the DMRS pilot sequence from the received signal and use the least squares method to calculate the channel characteristics of the pilot subcarrier positions, such as channel gain or phase, to obtain the CSI of the pilot positions. For non-pilot subcarrier positions, the complete CSI of the data subcarriers within the full bandwidth can be obtained by linearly extrapolating from the CSI of adjacent pilots and using the nearest neighbor interpolation method, thereby understanding the overall impact of the channel on the signal. Subsequently, the target device can use the CSI obtained from channel estimation to design an equalizer using the minimum mean square error algorithm to perform reverse compensation on the received target channel data, such as canceling attenuation and correcting phase offset. After final equalization, the ciphertext channel signal transmitted by the base station can be successfully recovered.

[0125] S320. Decrypt the target channel data using the target security key.

[0126] Specifically, since both the sender and receiver have pre-built security key sets, after the target device recovers the encrypted channel signal sent by the base station, it can directly extract the target security key sequence number from it, and finally use the target security key sequence number to search in the security key set to obtain the target security key.

[0127] Next, the target device invokes a symmetric encryption algorithm consistent with the base station's encryption algorithm to decrypt the ciphertext channel signal using the target security key. Understandably, encryption scrambles the data using a key, while decryption restores the data using the same key. Furthermore, because artificial noise is transparent to the target device, the decryption process is unaffected by noise and can accurately restore the original data. After decryption, the target device obtains the original channel data and transmits it to the upper-layer application, ultimately presenting it as readable information.

[0128] It is important to note that in the downlink, the base station needs to use beamforming to direct the signal to the target device, while simultaneously adding artificial noise to interfere with eavesdroppers. In the uplink, however, the device does not need beamforming when sending data to the base station; the base station can obtain the raw data simply through channel estimation, equalization, and decryption.

[0129] In the above implementation, after receiving target channel data that has been directionally transmitted by the base station and superimposed with artificial noise, the target device can recover the ciphertext signal without distortion by using DMRS to perform channel estimation and MMSE equalization. Then, it can complete the decryption by matching the target security key in real time according to the sequence number using the local security key set. The artificial noise is transparent to it because of its zero traps and does not affect the demodulation and decryption process. This ensures confidential transmission of downlink data while maintaining high reception quality, significantly improving the system's anti-eavesdropping capability.

[0130] This specification also provides a data encryption transmission method, which includes the following steps:

[0131] S402. Based on the uplink pilot sequence of the target device, perform uplink channel estimation to obtain the channel response matrix of the target device.

[0132] S404. Generate a quantization sequence based on the channel response matrix, and use the quantization sequence to generate a secure key set.

[0133] S406. Determine the current security key sequence number based on the preset negotiation rules.

[0134] S408. Determine the target security key number using the current security key number and the preset offset.

[0135] S410. Use the target security key sequence number to search in the security key set to obtain the target security key.

[0136] S412. Determine the target security key from the security key set.

[0137] S414. Encrypt the original channel data using the target security key to obtain ciphertext channel data. The ciphertext channel data carries the target security key sequence number.

[0138] S416. Perform channel estimation based on the channel sounding reference signal to obtain the channel estimation parameters;

[0139] S418. Based on the channel estimation parameters, estimate the direction of arrival to obtain the target angle where the target device is located;

[0140] S420, Generate signal shaping factor based on target angle.

[0141] S422. Select multiple candidate noise angles within a preset angle range based on the target angle, and determine the noise shaping vector corresponding to each candidate noise angle;

[0142] S424. Based on the noise shaping vector corresponding to each candidate noise angle, perform projection calculation on the target angle to obtain the synthetic beam energy on the target angle.

[0143] S426. When the synthesized beam energy reaches the preset energy threshold, the noise shaping factor is determined by using the noise shaping vector corresponding to each candidate noise angle.

[0144] S428. Random beamforming processing is performed on the encrypted channel data using signal shaping factor and noise shaping factor to obtain target channel data with artificial noise; wherein, the artificial noise is determined based on the target angle between the base station and the target device, and the target device stores the target security key; the signal shaping factor and noise shaping factor are determined based on the channel sounding reference signal of the target device.

[0145] S430. Send the target channel data to the target device at the target angle so that the target device can decrypt the target channel data using the target security key; wherein there is no artificial noise on the target device.

[0146] It should be understood that although the steps in the flowchart above are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowchart above may include multiple steps or stages, which are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps.

[0147] This specification also provides a data encryption transmission device 400, such as... Figure 4 As shown, it includes: a key encryption module 410, a beamforming module 420, and a data transmission module 430, wherein:

[0148] The key encryption module 410 is used to encrypt the original channel data using the target security key to obtain ciphertext channel data.

[0149] The beamforming module 420 is used to perform random beamforming processing on the encrypted channel data to obtain target channel data with artificial noise; wherein, the artificial noise is determined based on the target angle between the base station and the target device, and the target device stores the target security key.

[0150] The data transmission module 430 is used to send target channel data to the target device at the target angle, so that the target device can decrypt the target channel data using the target security key; wherein, there is no artificial noise on the target device.

[0151] In some embodiments, the beamforming module 420 is further configured to perform random beamforming processing on the ciphertext channel data using a signal shaping factor and a noise shaping factor to obtain target channel data; wherein the signal shaping factor and the noise shaping factor are determined based on the channel sounding reference signal of the target device.

[0152] In some implementations, the beamforming module 420 is also used to perform channel estimation based on the channel sounding reference signal to obtain channel estimation parameters; perform direction of arrival estimation based on the channel estimation parameters to obtain the target angle where the target device is located; and generate a signal shaping factor based on the target angle.

[0153] In some implementations, the beamforming module 420 is further configured to perform channel estimation based on the channel sounding reference signal to obtain channel estimation parameters; perform direction of arrival estimation based on the channel estimation parameters to obtain the target angle where the target device is located; select multiple candidate noise angles within a preset angle range based on the target angle, and determine the noise shaping vector corresponding to each candidate noise angle; perform projection calculation on the target angle based on the noise shaping vector corresponding to each candidate noise angle to obtain the synthetic beam energy at the target angle; and determine the noise shaping factor using the noise shaping vector corresponding to each candidate noise angle when the synthetic beam energy reaches a preset energy threshold.

[0154] In some embodiments, a data encryption transmission device 400 further includes a key determination module, which is used to determine the current security key sequence number based on a preset negotiation rule; determine the target security key sequence number using the current security key sequence number and a preset offset; and search in the security key set using the target security key sequence number to obtain the target security key.

[0155] In some implementations, the key determination module is also used to perform uplink channel estimation based on the uplink pilot sequence of the target device to obtain the channel response matrix of the target device; generate a quantization sequence based on the channel response matrix; and use the quantization sequence to generate a secure key set.

[0156] In some implementations, the target security key has a target security key serial number; the key encryption module 410 is also used to encrypt the original channel data using the target security key to obtain ciphertext channel data; wherein the ciphertext channel data carries the target security key serial number.

[0157] For specific limitations regarding a data encryption transmission device, please refer to the limitations regarding a data encryption transmission method described above, which will not be repeated here. Each module in the aforementioned data encryption transmission device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0158] In this embodiment, a data encryption transmission device is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above-mentioned functions.

[0159] This application also provides a communication device. It should be noted that this communication device can be a base station, a target device, or a computer device, and its internal structure diagram can be as follows: Figure 5 As shown. The computer device includes a processor, memory, communication interface, display screen, and input device connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a data encryption transmission method. The display screen can be an LCD screen or an e-ink screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device casing, or an external keyboard, touchpad, or mouse. Those skilled in the art will understand that… Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0160] This application also provides a computer-readable storage medium. The methods described in this application can be implemented in hardware or firmware, or implemented as recordable on a storage medium, or implemented as computer code downloaded over a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and subsequently stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the methods shown in the above embodiments are implemented.

[0161] This application provides a computer program product including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the method of any embodiment of this application.

[0162] The data encryption transmission method, decryption method, communication device, and storage medium described in the above embodiments can be implemented by a computer chip or physical entity, or by a product with a certain function. A typical implementing device is a computer. Specifically, the computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices. For ease of description, the above devices are described separately by function as various units. Of course, in implementing this application, the functions of each unit can be implemented in one or more software and / or hardware.

[0163] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create an implementation for the process. Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0164] In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise expressly specified. It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further restrictions, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes said element.

[0165] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. Since they are fundamentally similar to the method embodiments, the descriptions are relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The above descriptions are merely embodiments of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application. Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for encrypted data transmission, characterized in that, Applied to a base station, the method includes: The original channel data is encrypted using the target security key to obtain ciphertext channel data; The encrypted channel data is subjected to random beamforming processing to obtain target channel data with artificial noise; wherein the artificial noise is determined based on the target angle between the base station and the target device, and the target device stores the target security key; The target channel data is sent to the target device at the target angle, so that the target device can decrypt the target channel data using the target security key; wherein, there is no artificial noise on the target device.

2. The method according to claim 1, characterized in that, The step of performing random beamforming processing on the encrypted channel data to obtain target channel data with artificial noise includes: The encrypted channel data is subjected to random beamforming processing using a signal shaping factor and a noise shaping factor to obtain the target channel data; wherein the signal shaping factor and the noise shaping factor are determined based on the channel sounding reference signal of the target device.

3. The method according to claim 2, characterized in that, The signal shaping factor is determined in the following manner: Channel estimation is performed based on the channel sounding reference signal to obtain channel estimation parameters; Based on the channel estimation parameters, the direction of arrival is estimated to obtain the target angle where the target device is located; The signal shaping factor is generated based on the target angle.

4. The method according to claim 2, characterized in that, The noise shaping factor is determined in the following manner: Channel estimation is performed based on the channel sounding reference signal to obtain channel estimation parameters; Based on the channel estimation parameters, the direction of arrival is estimated to obtain the target angle where the target device is located; Based on the target angle, select multiple candidate noise angles within a preset angle range, and determine the noise shaping vector corresponding to each candidate noise angle; Based on the noise shaping vector corresponding to each candidate noise angle, the composite beam energy at the target angle is calculated by projecting it onto the target angle. When the synthesized beam energy reaches a preset energy threshold, the noise shaping factor is determined using the noise shaping vector corresponding to each candidate noise angle.

5. The method according to claim 1, characterized in that, The target security key is determined in the following ways: The current security key sequence number is determined based on preset negotiation rules; The target security key number is determined using the current security key number and the preset offset; The target security key is obtained by searching the security key set using the target security key serial number.

6. The method according to claim 5, characterized in that, The security key set is determined by the following methods: Uplink channel estimation is performed based on the uplink pilot sequence of the target device to obtain the channel response matrix of the target device. A quantization sequence is generated based on the channel response matrix, and the security key set is generated using the quantization sequence.

7. The method according to claim 1, characterized in that, The target security key has a target security key serial number; The step of encrypting the original channel data using the target security key to obtain ciphertext channel data includes: The original channel data is encrypted using the target security key to obtain ciphertext channel data; wherein, the ciphertext channel data carries the target security key sequence number.

8. A data decryption method, characterized in that, The method is applied to a target device located at a target orientation of a base station, the target orientation corresponding to a target angle, the target device storing a target security key, and the base station storing a set of security keys; the method includes: The system receives target channel data transmitted by the base station; wherein the target channel data is accompanied by artificial noise determined based on the target angle, and the target device does not have the artificial noise; the target channel data is obtained by performing random beamforming processing on ciphertext channel data, and the ciphertext channel data is obtained by encrypting the original channel data using the target security key in the security key set; The target channel data is decrypted using the target security key.

9. A communication device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method of any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method of any one of claims 1 to 7.

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