A user access control method based on resource hopping multiple access scheme

Abstract

This invention provides a user access control method based on a resource hop multiple access (RHMA) scheme. The method includes: a base station dividing all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns; the base station assigns usable RHMA resource hop patterns to users and broadcasts them; a transceiver is set up near the base station, and the transceiver assigns unusable RHMA resource hop patterns to unauthorized users, broadcasting the RHMA resource hop pattern information assigned to unauthorized users at a higher power; when an unauthorized user attempts to access the base station using an unusable RHMA resource hop pattern assigned by the transceiver, the base station refuses access to the unauthorized user using that unusable RHMA resource hop pattern. This invention utilizes a transceiver to transmit incorrect resource hop patterns to unauthorized users, thereby enabling the base station to identify the existence of unauthorized users during user identification and thus preventing unauthorized user access.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a user access control method based on a resource hop multiple access scheme. Background Technology

[0002] Non-orthogonal multiple access (NOMA), as an emerging multiple access technology, has received widespread attention and research in the field of communications in recent years. Among these, for unlicensed random access systems, considering the sporadic activation characteristics of massive user access in large-scale Internet of Things (IoT) applications, and addressing the limitations of existing multiple access technologies in resolving collisions under high-concurrency user access conditions, researchers have proposed a novel multiple access scheme called Resource Hopping based Multiple Access (RHMA). The RHMA scheme primarily considers achieving multi-user access by hopping between multiple channel resources, mapping different data segments to different channel resources, ensuring that each user uses a unique resource hopping pattern, thereby allowing a large number of users to access the system.

[0003] 1. RHMA's resource skipping scheme

[0004] (1) Resource Jump Method

[0005] After segmenting user data packets, they are processed. Different data segments from each user are mapped using the same or different channel resources. Considering q channel resources, E = {e1, e2, ..., e...} q This approach can spread each data segment using mutually orthogonal spreading sequences, or map each data segment to the same or different subcarriers. Thus, all K connected users have different channel resource mapping combinations, called resource hopping patterns. By arranging and combining limited channel resources into a large number of resource mapping patterns, all of which constitute a resource mapping pattern codebook, massive user access can be achieved. This resource mapping process can be viewed as users hopping between various channel resources; hence, it is called a resource hopping mapping scheme.

[0006] (2) Resource Jump Pattern Codebook Design

[0007] In an unlicensed random access scheme based on resource hopping patterns, if two different connected users are mapped to the same channel resource on the same data segment, a collision will occur if both users are active simultaneously within that time slot. This scheme utilizes segment coding to resolve a limited number of data segment collisions. Therefore, when designing the resource hopping pattern, the number of colliding segments between active users must be controlled to ensure reliable user identification and the performance of recovering colliding data segments using redundant data segments. Consider dividing user data packets into n segments, where the maximum number of colliding segments between any two connected users is r, i.e., the number of identical segments in any resource hopping pattern is r. This translates to a minimum Hamming distance of nr between two codewords. Based on the Singleton bound, the maximum number of codewords satisfying the condition is q. r+1 Then, using the maximum distance separable code (MDS), a code suitable for a maximum number of connected users q is generated. r+1 The resource mapping pattern is as follows: Where c i Let K be a sequence of length n, consisting of 0s and 1s, corresponding to the resource mapping codeword of one user. For K < q r+1 If there are multiple users, then K patterns will be selected from all resource mapping patterns C and assigned to the users.

[0008] 2. RHMA transmitter design scheme

[0009] (1) Channel coding

[0010] To activate user data transmission, channel coding is first performed using convolutional coding with a channel coding code rate of ρ. c After encoding, user k's data bits are b k .

[0011] (2) Data segmentation

[0012] The channel-coded user data is divided into m segments, represented as follows: Where b k This represents the number of data bits for user k. i represents the user data segment number.

[0013] (3) Segment coding

[0014] The message data is segmented using MDS codes to generate nm redundant bits. The specific implementation process is as follows: Each data segment is converted into The finite field elements in the vector represent the resulting data as a 1×m row vector. Multiplying it by an m×n matrix in a finite field, the segment code is represented as: The encoded finite field elements are then represented in binary form to obtain n encoded data segments.

[0015] (4) Data modulation

[0016] Using the BPSK debugging method, after generating redundant segments, the data bits in all n segments are modulated into data symbols. in Here, the modulation symbols are selected from an augmented modulation alphabet A0 = {1, -1, 0}, and the symbol 0 represents an inactive user.

[0017] (5) Pilot insertion

[0018] After data modulation, in The insertion length at the beginning of each modulation symbol segment is l p pilot sequence The data after inserting the pilot signal is represented as follows:

[0019] in

[0020] (6) Resource Mapping

[0021] Mapping the transmitted active user data segments to channel resources can be represented by spreading each data segment using an orthogonal spreading sequence, or by mapping each data segment using subcarriers. This process can be simply understood as mapping each user's transmitted data to codewords in a pre-designed resource mapping codebook. The mapped data segments of each active user and their corresponding channel resources can be represented by a multidimensional matrix X, where X is... The matrix can represent the q channel resources and K respectively. a Activated users Mapping relationships between data.

[0022] (7) Data segment synthesis

[0023] The user data, after being segmented, is reassembled into a single segment and then sent into the channel for transmission.

[0024] 3. RHMA Receiver Design Scheme

[0025] (1) Data segmentation

[0026] The received data is re-segmented to facilitate subsequent signal processing and transmission.

[0027] (2) Energy detection

[0028] Energy detection involves detecting the mapping resource status of each data segment. Based on the orthogonality between mapping resources, the energy detection of the data received by the corresponding mapping resource for the i-th data segment is represented as r. i,j =|y i,j H yi,j |, among which For the received transmission data corresponding to the i-th segment and the j-th channel resource, the energy detection value r is... i,j With the judgment threshold V t By comparison, it can be determined whether the received data of the i-th segment uses e. j Resource mapping, the set of mapped resources for the i-th segment is denoted as Ω. i =Ω i ∪e j .

[0029] (3) User identification

[0030] Based on the energy detection results of each segment, the correspondence between mapped resources and users can be determined from the pre-designed resource mapping pattern codebook. Therefore, the method using e in the i-th segment can be identified. j The users form a user set G. j,i We can obtain the user set U of the i-th segment. i =U i ∪G j,i The final set of activated users can be obtained by taking the intersection of the potential users identified in each segment. After successful user identification, the receiver can know the collision segment situation among all active users in the time slot. The receiver then observes the collision segment situation of each user, deletes all users whose data segments are collision segments, thereby eliminating false alarm users caused by collisions, and then identifies all decodable users and their corresponding collision segment situations, which facilitates subsequent segment decoding operations.

[0031] (4) Resource demapping

[0032] For each identified user, the data on all n segments is demapped based on its channel resource mapping pattern, and the corresponding mapping process is performed. This process can be despreading or subcarrier demapping to recover the data before resource mapping.

[0033] (5) Channel estimation and equalization

[0034] In channel estimation, pilot symbols inserted from all received collision-free data segments of decodable users are used to perform channel estimation, obtaining an estimate of the channel fading experienced by user k. This channel estimate is then used to recover the fading signal values ​​from the collision-free data segments of the decodable users.

[0035] (6) Data demodulation

[0036] In data demodulation, the demodulation scheme corresponding to BPSK modulation is used for data demodulation. After removing the added pilot symbols, the demodulated data bits are obtained as follows:

[0037] and

[0038] (7) Segment Decoding

[0039] In segment decoding, since the receiver already knows the collision segment situation of each decodeable user, it can directly delete all the collided data segments within the last n coded data segments to obtain m collision-free coded data segments. These segments are then input into the encoder for segment decoding to recover the remaining collided coded data segments, finally yielding m segment decoded data segments.

[0040] (8) Data segment synthesis

[0041] m segments of decoded data after segment decoding Merge into a single data segment Enter channel decoding.

[0042] (9) Channel Decoding

[0043] Using convolutional codes to perform channel decoding processing corresponding to the transmitter, we obtain...

[0044] In RHMA, the base station periodically assigns a unique resource hop pattern to each user via broadcast. Upon receiving the resource hop pattern assignment information, the user sends an acknowledgment to the base station, thus completing the assignment. In this large-scale machine-type communication system, all users are assigned their own identities. The base station generates resource hop pattern assignment information in the form of user identity plus the assigned resource hop pattern and broadcasts it to all users. For unauthorized users, existing RHMA systems can stop assigning resource hop patterns to them, causing them to fail to access the system due to the lack of a correct resource hop pattern.

[0045] The disadvantages of the existing RHMA scheme described above include: the scheme requires the base station to prevent unauthorized users from accessing the network; however, when the base station does not have information about unauthorized users, it cannot prevent them from accessing the network itself. In this case, if a signal jammer is used to block unauthorized users, the base station will not receive the confirmation information from the unauthorized user, and will therefore repeatedly send the RHMA resource hop pattern allocation information for that user, resulting in a waste of signaling resources. Summary of the Invention

[0046] Embodiments of the present invention provide a user access control method based on a resource hop multiple access scheme to enable base stations to effectively identify unauthorized users.

[0047] To achieve the above objectives, the present invention adopts the following technical solution.

[0048] A user access control method based on a resource hop multiple access scheme includes:

[0049] The base station divides all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns. The base station allocates the usable RHMA resource hop patterns to users and broadcasts the information to users about the allocated usable RHMA resource hop patterns.

[0050] A transceiver is set up near the base station. The transceiver obtains the RHMA resource hop pattern information allocated by the base station to all users through the base station broadcast information. The transceiver then assigns unusable RHMA resource hop patterns to unauthorized users.

[0051] When the base station sends the next broadcast RHMA resource hop pattern allocation information, the transceiver broadcasts the RHMA resource hop pattern information it has allocated to the illegal user at a higher power.

[0052] When an unauthorized user attempts to access the base station using an unusable RHMA resource hop pattern allocated by the transceiver, the base station refuses the access of the unauthorized user using that unusable RHMA resource hop pattern.

[0053] Preferably, the base station divides all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns. The base station allocates the usable RHMA resource hop patterns to users and broadcasts the allocated usable RHMA resource hop pattern information to users, including:

[0054] The base station uses RHMA's resource hop pattern design algorithm to generate q r+1 A jump pattern for RHMA resources, q r+1 The RHMA resource jump pattern is divided into K w A set of usable RHMA resource jump patterns and K b A set of unusable RHMA resource jump patterns, K w +K b =q r+1 The base station will K w The base station assigns a usable RHMA resource hop pattern to the user, and does not inform the user of the unusable RHMA resource hop patterns or the usable RHMA resource hop patterns.

[0055] Preferably, the transceiver is positioned near the base station. The transceiver obtains the RHMA resource hop patterns allocated by the base station to all users through base station broadcast information. The transceiver then allocates unusable RHMA resource hop pattern sets to unauthorized users, including:

[0056] A transceiver is deployed within a distance R near the base station. The transceiver has both legitimate and illegitimate user identity information, and all users in the system are unaware of its existence. The transceiver listens to the periodic broadcast information of the base station to obtain the RHMA resource skipping pattern allocated to the user by the base station.

[0057] The transceiver generates all q based on the RHMA resource skip pattern design algorithm. r+1 A resource jumping pattern, q r+1 Subtracting the RHMA resource hop pattern allocated to the user by the base station from the resource hop pattern yields a set of unusable RHMA resource hop patterns. The transceiver then allocates the set of unusable RHMA resource hop patterns to unauthorized users.

[0058] Preferably, when the base station next transmits broadcast RHMA resource hop pattern allocation information, the transceiver broadcasts the RHMA resource hop pattern information it allocated to the illegal user at a higher power, including:

[0059] During the next RHMA resource hop pattern allocation information broadcast cycle of the base station, the transceiver's transmit power is set to:

[0060] P TX (dB)=P BS (dB)+20lg R+10 (1)

[0061] Where P BS (dB) represents the dB value of the base station's transmit power;

[0062] The transceiver uses P TX (dB) Power broadcasts the RHMA resource hopping patterns that the base station assigns to unauthorized users and the RHMA resource hopping patterns that the base station assigns to authorized users.

[0063] On the receiver side of both legitimate and illegitimate users, if the RHMA resource hopping pattern broadcast by the transceiver is correctly decoded, an acknowledgment (ACK) message is sent; if the decoding fails, a failure (NACK) message is sent. The transceiver listens for feedback from both legitimate and illegitimate users. If no feedback is received from either user, the transceiver retransmits the RHMA resource hopping pattern it assigned to the illegitimate user and the RHMA resource hopping pattern assigned by the base station to the legitimate user.

[0064] Preferably, when an unauthorized user accesses the base station using an unusable RHMA resource hop pattern allocated by the transceiver, the base station refuses access to the unauthorized user using that unusable RHMA resource hop pattern, including:

[0065] When the receiver of an unauthorized user correctly decodes the RHMA resource hopping pattern broadcast by the transceiver, the unauthorized user uses an unusable RHMA resource hopping pattern assigned to it by the transceiver to access the base station. When the base station detects that a user is using an unusable RHMA resource hopping pattern during user identification, it confirms that an unauthorized user is requesting access and rejects the access of the unauthorized user.

[0066] As can be seen from the technical solutions provided by the embodiments of the present invention described above, the embodiments of the present invention utilize an additional transceiver to transmit erroneous resource hopping patterns to unauthorized users and enable the unauthorized users to send back confirmation information to the base station. This allows the base station to identify the existence of unauthorized users during user identification, thereby preventing unauthorized users from accessing the base station. Furthermore, the base station does not need to repeatedly send resource hopping pattern allocation information to unauthorized users, thus avoiding a waste of signaling resource overhead.

[0067] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0068] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0069] Figure 1 A flowchart illustrating a user access control method based on a resource hop multiple access scheme provided in an embodiment of the present invention;

[0070] Figure 2 This is a schematic diagram illustrating the deployment of additional transceivers around a base station, as provided in an embodiment of the present invention.

[0071] Figure 3 This is a schematic diagram illustrating how legitimate and illegitimate users send feedback information to a base station and transceiver, as provided in an embodiment of the present invention.

[0072] Figure 4 This is a schematic diagram illustrating the access failure probability of illegal and legitimate users, provided as an embodiment of the present invention. Detailed Implementation

[0073] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0074] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or couplings. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0075] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0076] To facilitate understanding of the embodiments of the present invention, the following will provide further explanation and description with reference to the accompanying drawings and several specific embodiments. These embodiments do not constitute a limitation on the embodiments of the present invention.

[0077] This invention proposes to utilize an additional transceiver to transmit erroneous resource hop patterns to unauthorized users, and to enable the unauthorized users to send back confirmation information to the base station. This allows the base station to identify the presence of unauthorized users during user identification, thereby preventing unauthorized users from accessing the base station. Furthermore, this eliminates the need for the base station to repeatedly send resource hop pattern allocation information to unauthorized users, thus avoiding the waste of signaling resources.

[0078] This invention provides a user access control method based on a resource hop multiple access scheme, offering an alternative solution to address the security issues of user access control in large-scale machine-type communication scenarios. It considers the situation where unauthorized users exist in the large-scale machine-type communication system and their identities are unknown to the base station, by deploying additional transceivers to manage these unauthorized users. In this scheme, the deployed additional transceivers possess the identity information of both legitimate and unauthorized users, and also have the base station's transmit power information.

[0079] In this invention, an additional transceiver is configured. This transceiver is an additional device system that does not belong to the large-scale machine-type communication system. It can detect unauthorized users and obtain their information through signal reconnaissance, data content analysis, and data traffic analysis. However, since this transceiver does not belong to the large-scale machine-type communication system, it is in a non-cooperative state with the system's base station.

[0080] The processing flow of a user access control scheme based on a resource hop multiple access scheme provided in this embodiment of the invention is as follows: Figure 1 As shown, the processing steps include the following:

[0081] Step S1: The system divides all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns. The base station allocates the usable RHMA resource hop patterns to users and broadcasts this information to them. The base station does not inform users of the unusable patterns or the information on the usable RHMA resource hop patterns.

[0082] Step S2: Set up an additional transceiver near the base station. This transceiver obtains the RHMA resource hopping pattern allocated by the base station to all users through the base station broadcast information.

[0083] Step S3: When the base station sends the RHMA resource hop pattern allocation information again, the transceiver will broadcast the RHMA resource hop pattern allocation information at high power.

[0084] Step S4: The transceiver listens for feedback information from both legitimate and illegitimate users;

[0085] Step S5: If no feedback information is received from legitimate or illegitimate users, the transceiver will repeatedly send the resource skip pattern allocation information.

[0086] Specifically, step S1 includes: the base station generating q using the RHMA resource hop pattern design algorithm. r+1 A jump pattern for RHMA resources, q r+1 The RHMA resource jump pattern is divided into K w A usable RHMA resource jump pattern and K b A set of unusable RHMA resource jump patterns, K w +K b =q r+1 During resource hop pattern allocation, the base station will use K. w A resource skipping pattern can be assigned to users, and the base station does not know which users are legitimate or illegitimate.

[0087] And retain Kb The set of unusable RHMA resource hop patterns is not allocated. The base station does not disclose the information about unusable and usable RHMA resource hop patterns to all legitimate and illegitimate users. The reason for setting up usable and unusable RHMA resource hop patterns here is to ensure that additional transceivers in subsequent steps have resource mapping patterns available to allocate to illegitimate users. That is, when the base station allocates all usable RHMA resource hop patterns to users, the transceiver can select a resource hop pattern from the unusable patterns and allocate it to the illegitimate user.

[0088] Specifically, step S2 above includes: a schematic diagram of deploying additional transceivers around the base station side provided in the embodiments of the present invention, as shown in the figure. Figure 2 As shown, an additional transceiver is deployed within a distance R near the base station. This transceiver is an additional device system not belonging to the large-scale machine-type communication system (MLC). It can detect unauthorized users and obtain their information through signal reconnaissance, data content analysis, and data traffic analysis. Therefore, this transceiver possesses both legitimate and unauthorized user identity information, and neither legitimate nor unauthorized users in the system are aware of its existence. The arrangement of the additional transceiver knowing the legitimate and unauthorized user identities while the base station remains unaware is intended to utilize the additional transceiver to manage users within the MLC, thereby achieving the goal of providing corresponding public safety services. Since the additional transceiver is not part of the MLC and is not a user within it, it operates in a non-cooperative state with the base station. Therefore, even though the additional transceiver possesses the legitimate and unauthorized user identity information, it cannot directly inform the base station.

[0089] The transceiver listens to the base station's periodic broadcast information and extracts the RHMA resource hopping patterns for legitimate and illegitimate users. At this point, the transceiver has acquired all the RHMA resource hopping patterns allocated to users by the base station. Then, based on the RHMA resource hopping pattern design algorithm, the transceiver generates all q... r+1 The transceiver obtains resource hop patterns from all q. Based on the RHMA resource hop patterns allocated to users by the base station, it can be determined that the base station has not allocated resource hop patterns to users (including unusable RHMA resource hop patterns). In other words, the transceiver obtains resource hop patterns from all q. r+1 Subtracting the resource hop pattern allocated to the user by the base station from the resource hop pattern yields the RHMA resource hop pattern that the base station does not use (including unusable RHMA resource hop patterns).

[0090] Specifically, step S3 includes: during the next resource hop pattern allocation information broadcast cycle of the base station, setting the transceiver's transmit power to:

[0091] P TX (dB)=P BS (dB)+20lgR+10 (1)

[0092] Where P BS (dB) represents the dB value of the base station's transmit power. The transceiver broadcasts resource hop pattern allocation information at this power. Since the transceiver knows the RHMA resource hop patterns allocated to all legitimate users by the base station in step 2, and can obtain the RHMA resource hop patterns that the base station is not using (including unusable patterns), the RHMA resource hop patterns allocated to legitimate users in the RHMA resource hop pattern allocation information broadcast by the transceiver are consistent with the RHMA resource hop patterns allocated by the base station, while the RHMA resource hop patterns allocated to illegitimate users are selected from the RHMA resource hop patterns that the base station is not using (including unusable patterns). b Select from the unusable patterns for allocation.

[0093] At the receivers of both legitimate and illegitimate users, the transceiver's broadcast signal will overlay the base station's broadcast signal. That is, the information decoded at the receiver's end for both legitimate and illegitimate users is the RHMA resource hop pattern allocation information broadcast by the transceiver at high power, while the base station's broadcast signal will be masked as noise. Since legitimate and illegitimate users are unaware of the transceiver's existence, they still believe the received RHMA resource hop pattern allocation information is sent by the base station, and therefore directly use the RHMA resource hop pattern allocated to them for access. For illegitimate users, lacking both usable and unusable RHMA resource hop patterns, they will believe they are still receiving RHMA resource hop pattern allocation information from the base station, unaware that they are actually receiving RHMA resource hop pattern allocation information from the transceiver. Therefore, illegitimate users will use the incorrect, unusable RHMA resource hop pattern allocated to them by the transceiver to access the base station.

[0094] Specifically, step S4 above includes: Figure 3This is a schematic diagram illustrating how legitimate and illegitimate users send feedback information to a base station and transceiver, as provided in an embodiment of the present invention. After the transceiver broadcasts RHMA resource hop pattern allocation information, it begins listening for feedback information from legitimate and illegitimate users. If a legitimate or illegitimate user correctly decodes the RHMA resource hop pattern allocation information, it sends an acknowledgment (ACK) message; if the user decodes incorrectly, it sends a failure (NACK) message. In this system, both the base station and the transceiver receive the user's feedback information. If an illegitimate user correctly decodes the RHMA resource hop pattern allocation information broadcast by the transceiver, and does not possess an unusable pattern or a usable RHMA resource hop pattern, the illegitimate user considers that it has correctly received the pattern allocation information from the base station, and therefore sends an ACK message, which is simultaneously received by the base station and the transceiver. Upon receiving the ACK message from the illegitimate user, the transceiver considers that the illegitimate user has successfully received the RHMA resource hop pattern allocation information it sent and will use the incorrectly allocated RHMA resource hop pattern. At the same time, the base station also receives the ACK information from the unauthorized user. It will mistakenly believe that the unauthorized user has successfully received the resource jump pattern allocation information it sent, and will therefore stop sending it repeatedly, thus saving signaling overhead.

[0095] In subsequent unlicensed random access, if an unauthorized user is activated, they will use an incorrect RHMA resource hop pattern allocated by the additional transceiver to access the base station. When the base station detects an unusable RHMA resource hop pattern during user identification, it indicates that an unauthorized user is requesting access, and the base station will refuse access to the unauthorized user using the unusable RHMA resource hop pattern during user identification.

[0096] Specifically, step S5 above includes the following process: the transceiver repeatedly transmits pattern allocation information as follows:

[0097] If a legitimate or illegitimate user fails to decode the resource hop pattern allocation information broadcast by the transceiver, it sends a NACK message to both the transceiver and the base station. When the base station and transceiver receive the NACK message from the user, they retransmit the user's pattern allocation information. During this retransmission, if the base station's transmit power is P... BS (dB), the transceiver's transmit power is P TX (dB), and the relationship between the two is shown in formula (1).

[0098] Figure 4 This diagram illustrates the probability of access failure for both unauthorized and authorized users, as provided in an embodiment of the present invention. Figure 4As shown, a two-user access system was implemented in a real communication environment created using a USRP B210 device and MATLAB software, based on the method provided in this embodiment of the invention. The two users are an illegal user (User 1) and a legitimate user (User 2). The system utilizes different subcarrier groups of OFDM (Orthogonal Frequency Division Multiplexing) as carriers for channel resource hopping, realizing a resource hopping multiple access scheme. Both users transmit data to the base station in the 900MHz frequency band, and the block error rate (BLER) diagram of reliable data transmission for the two access users is obtained. BLER represents the probability of user access failure. It can be seen that, based on the method provided in this embodiment of the invention, the access failure probability of the illegal user is 1, while the access failure probability of the legitimate user can reach 10. -3 The following demonstrates that the scheme can effectively control user access.

[0099] In summary, the method of this invention can achieve user access control by setting up an additional transceiver when the base station is unaware of the existence of unauthorized users. It can also deceive unauthorized users into using incorrect RHMA resource hop patterns to access the network, thereby causing the base station to detect and deny their access during user identification. Simultaneously, this scheme deceives unauthorized users into sending ACK information for RHMA resource hop pattern allocation, eliminating the need for the base station to repeatedly send RHMA resource hop pattern allocation information to unauthorized users, thus saving signaling resource overhead.

[0100] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0101] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of the present invention.

[0102] 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 describing the differences from other embodiments. In particular, for apparatus or system embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The apparatus and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0103] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A user access control method based on a resource hop multiple access scheme, characterized in that, include: The base station divides all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns. The base station allocates the usable RHMA resource hop patterns to users and broadcasts the information to users about the allocated usable RHMA resource hop patterns. A transceiver is set up near the base station. The transceiver obtains the RHMA resource hop pattern information allocated by the base station to all users through the base station broadcast information. The transceiver then assigns unusable RHMA resource hop patterns to unauthorized users. When the base station sends the next broadcast RHMA resource hop pattern allocation information, the transceiver broadcasts the RHMA resource hop pattern information it has allocated to the illegal user at a higher power. When an unauthorized user attempts to access the base station using an unusable RHMA resource hop pattern allocated by the transceiver, the base station refuses the access of the unauthorized user using that unusable RHMA resource hop pattern.

2. The method according to claim 1, characterized in that, The base station divides all generated RHMA resource hop patterns into a set of usable RHMA resource hop patterns and a set of unusable RHMA resource hop patterns. The base station allocates the usable RHMA resource hop patterns to users and broadcasts the allocated usable RHMA resource hop pattern information to users, including: The base station uses RHMA's resource hop pattern design algorithm to generate q r+1 A jump pattern for RHMA resources, q r+1 The RHMA resource jump pattern is divided into K w A set of usable RHMA resource jump patterns and K b A set of unusable RHMA resource jump patterns, K w +K b =q r+1 The base station will K w The base station assigns a usable RHMA resource hop pattern to the user, and does not inform the user of the unusable RHMA resource hop patterns or the usable RHMA resource hop patterns.

3. The method according to claim 2, characterized in that, The transceiver is set up near the base station. The transceiver obtains the RHMA resource hop patterns allocated by the base station to all users through base station broadcast information. The transceiver then allocates the set of unusable RHMA resource hop patterns to unauthorized users, including: A transceiver is deployed within a distance R near the base station. The transceiver has both legitimate and illegitimate user identity information, and all users in the system are unaware of its existence. The transceiver listens to the periodic broadcast information of the base station to obtain the RHMA resource skipping pattern allocated to the user by the base station. The transceiver generates all q based on the RHMA resource skip pattern design algorithm. r+1 A resource jumping pattern, q r+1 Subtracting the RHMA resource hop pattern allocated to the user by the base station from the resource hop pattern yields a set of unusable RHMA resource hop patterns. The transceiver then allocates the set of unusable RHMA resource hop patterns to unauthorized users.

4. The method according to claim 3, characterized in that, When the base station next transmits broadcast RHMA resource hop pattern allocation information, the transceiver broadcasts its own RHMA resource hop pattern information allocated to unauthorized users at a higher power, including: During the next RHMA resource hop pattern allocation information broadcast cycle of the base station, the transceiver's transmit power is set to: P TX (dB)=P BS (dB)+20lg R+10 (1) Where P BS (dB) represents the dB value of the base station's transmit power; The transceiver uses P TX (dB) Power broadcasts the RHMA resource hopping patterns that the base station assigns to unauthorized users and the RHMA resource hopping patterns that the base station assigns to authorized users. On the receiver side of both legitimate and illegitimate users, if the RHMA resource hopping pattern broadcast by the transceiver is correctly decoded, an acknowledgment (ACK) message is sent; if the decoding fails, a failure (NACK) message is sent. The transceiver listens for feedback from both legitimate and illegitimate users. If no feedback is received from either user, the transceiver retransmits the RHMA resource hopping pattern it assigned to the illegitimate user and the RHMA resource hopping pattern assigned by the base station to the legitimate user.

5. The method according to claim 4, characterized in that, When an unauthorized user attempts to access the base station using an unusable RHMA resource hop pattern allocated by the transceiver, the base station refuses access to the unauthorized user using that unusable RHMA resource hop pattern, including: When the receiver of an unauthorized user correctly decodes the RHMA resource hopping pattern broadcast by the transceiver, the unauthorized user uses an unusable RHMA resource hopping pattern assigned to it by the transceiver to access the base station. When the base station detects that a user is using an unusable RHMA resource hopping pattern during user identification, it confirms that an unauthorized user is requesting access and rejects the access of the unauthorized user.

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