Cellular network user screening method and system based on multi-stage accurate interference

Abstract

This application discloses a method and system for shielding on-network users in cellular networks based on multi-level precise interference, belonging to the field of wireless communication technology. The method includes: scanning surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; calculating the fixed time-frequency position of the physical control format indication channel based on the physical layer cell identifier and system bandwidth and transmitting a first-level interference signal; calculating a candidate position set for the physical downlink control channel, the candidate position set including candidate positions in the common search space and estimated positions in the user-dedicated search space, and transmitting a second-level interference signal on the time-frequency resources corresponding to the candidate position set; reserving a periodic measurement window, disabling interference transmission and performing fast energy detection within the measurement window to identify the actually occupied control channel units, and dynamically adjusting the candidate position set based on the detection results; abandoning the full-bandwidth interference suppression method, thus improving the accuracy and efficiency of shielding.

Description

Technical Field

[0001] This application belongs to the field of wireless communication technology, and specifically relates to a method and system for shielding on-network users in a cellular network based on multi-level precise interference. Background Technology

[0002] Currently, there are two main technical solutions for digital signal jammers. One solution covers the entire bandwidth of the operator's cell in the frequency domain and is continuous in time (continuous in downlink subframes in TDD). This solution requires high-bandwidth RF front-end support, resulting in higher cost and power consumption. The other solution only interferes with the time-frequency domain of the key channel, such as interfering only with the time-frequency domain of the synchronization signal. This reduces the dependence on high-specification chips and devices and improves the jamming efficiency. However, this solution is only effective for users who are currently accessing or about to access the network, and cannot achieve the jamming effect for users who are already on the network. Summary of the Invention

[0003] To address the current problem of failing to shield users already on the network by interfering with the time-frequency domain location of synchronization signals, this application provides a method to shield users already on the network. It abandons the full-bandwidth interference suppression approach and instead interferes with key channels such as PCFICH and PDCCH, thereby improving the accuracy and efficiency of the shielding.

[0004] This application provides a method for blocking on-network users in cellular networks based on multi-level precise interference, including: Scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; Based on the physical layer cell identifier and system bandwidth, calculate the fixed time-frequency position of the physical control format indicator channel and transmit the first-level interference signal; Calculate the candidate location set of the physical downlink control channel, the candidate location set including candidate locations in the common search space and estimated locations in the user-dedicated search space, and transmit a second-level interference signal on the time-frequency resources corresponding to the candidate location set; During the parallel transmission of the first-level and second-level interference signals, a periodic measurement window is reserved. Within the measurement window, interference transmission is turned off and fast energy detection is performed to identify the control channel units that are actually occupied. The candidate position set is then dynamically adjusted based on the detection results.

[0005] Optionally, the step of calculating the fixed time-frequency position of the physical control format indication channel and transmitting the first-level interference signal based on the physical layer cell identifier and system bandwidth includes: According to the LTE physical layer protocol, the frequency domain location of the resource unit group is determined by the physical layer cell identifier and the system bandwidth, and the resource unit group is evenly distributed across the entire system bandwidth. During the first orthogonal frequency division multiplexing symbol of each subframe, an interference signal is transmitted at the location of the resource unit group.

[0006] Optionally, the set of candidate locations for calculating the physical downlink control channel includes: Calculate candidate locations in the common search space, the candidate locations being determined by the starting point. It consists of an index and L consecutive control channel units, the starting... The index is determined based on the following formula:

[0007] Where L represents the aggregation level, Indicates the starting position, k represents the subframe index, and m represents the candidate index. Indicates the total number of control channel elements available in the current subframe; The distribution range of the user-specific search space is assessed, and the location is dynamically determined by the user RNTI using a hash function, taking the area within the control region. The middle preset ratio area of ​​the index serves as the estimated location of the user's dedicated search space; The candidate locations in the public search space are combined with the estimated locations in the user-specific search space to form the candidate location set.

[0008] Optionally, the periodically reserved measurement window includes: Every N subframes, the last few orthogonal frequency division multiplexing symbols of the last subframe are reserved as a measurement window, where N is a configurable positive integer.

[0009] Optionally, performing fast energy detection includes: Scan all control channel units (CCEs) within the control area; Measure the received power of each control channel element (CCE) and set an adaptive threshold; Control channel units (CCEs) whose received power exceeds the adaptive threshold are identified as actually occupied control channel units (CCEs).

[0010] Optionally, the dynamic adjustment includes: Compare the actually occupied control channel units with the current set of candidate locations; If more than a first preset proportion of the control channel units actually occupied are not in the current candidate location set, then the candidate location set is expanded and the newly occupied control channel units are added to the interference target. If more than a second preset proportion of control channel units in the current candidate location set are not actually occupied, then the candidate location set is reduced, unoccupied control channel units are removed, and a preset margin is retained.

[0011] Based on the same inventive concept, this application also provides a cellular network user shielding system based on multi-level precise interference, comprising: The scanning unit is used to scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; The first interference unit is used to calculate the fixed time-frequency position of the physical control format indication channel based on the physical layer cell identifier and system bandwidth, and to transmit the first-level interference signal. The second jamming unit is used to calculate the candidate position set of the physical downlink control channel, the candidate position set including candidate positions in the common search space and estimated positions in the user-dedicated search space, and to transmit a second-level jamming signal on the time-frequency resources corresponding to the candidate position set. The detection and adjustment unit is used to reserve a periodic measurement window during the parallel transmission of the first-level interference signal and the second-level interference signal, shut down the interference transmission and perform fast energy detection within the measurement window, identify the control channel units that are actually occupied, and dynamically adjust the candidate position set according to the detection results.

[0012] Optionally, the system further includes a synchronization module for synchronizing the first-level interference signal and the second-level interference signal with the target cell frame at a specific time, transmitting them during downlink subframes, and transmitting them at a power higher than the target cell reference signal power by a specific offset.

[0013] Furthermore, this application also provides a computing device, comprising: at least one processor and a memory; The memory is used to store one or more programs; When the one or more programs are executed by the one or more processors, a method for masking on-network users in a cellular network based on multi-level precise interference, as described above, is implemented.

[0014] Furthermore, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the above-described method for blocking on-network users in a cellular network based on multi-level precise interference.

[0015] Compared with the prior art, this application has the following advantages: This application provides a method and system for shielding on-network users in a cellular network based on multi-level precise interference, comprising: scanning surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; calculating the fixed time-frequency position of the physical control format indication channel based on the physical layer cell identifier and system bandwidth and transmitting a first-level interference signal; calculating a candidate position set for the physical downlink control channel, the candidate position set including candidate positions in the common search space and estimated positions in the user-dedicated search space, and transmitting a second-level interference signal on the time-frequency resources corresponding to the candidate position set; reserving a periodic measurement window during the parallel transmission of the first-level interference signal and the second-level interference signal, closing the interference transmission and performing fast energy detection within the measurement window to identify the actually occupied control channel units, and dynamically adjusting the candidate position set according to the detection results.

[0016] Through a multi-level interference mechanism, the interference target is extended from the "access phase" to the "service phase." The first level of interference targets the PCFICH channel, disrupting the terminal's judgment of the control area size. The second level of interference covers the common search space and possible areas of the user-dedicated search space of the PDCCH, blocking the reception of scheduling information by on-network users. The two levels of interference work together to achieve forced shielding of on-network users, filling the technical gap in existing synchronization signal interference schemes.

[0017] Compared to full-bandwidth suppression schemes, this invention restricts the transmission of interference signals to the limited time-frequency resources occupied by the control channel. Full-bandwidth suppression requires continuous transmission of interference signals across all OFDM symbols in the entire downlink subframe, while this invention only transmits interference signals at specific CCE candidate positions within the control region (typically occupying 1-3 OFDM symbols), reducing the proportion of interference duration. Furthermore, within the control region, this invention only covers the resource elements corresponding to the PDCCH candidate positions, rather than transmitting across the entire control region's bandwidth. This eliminates the need for the RF front-end to support continuous high-power transmission across the entire time and frequency domains, significantly reducing the dependence on the specifications and average power consumption of core components such as power amplifiers and digital-to-analog converters, thereby reducing equipment hardware costs and operating energy consumption.

[0018] A rapid energy detection and dynamic adjustment mechanism is introduced. By periodically scanning the received power of each CCE within the control area, the actual PDCCH resources used by the base station are identified, and the interference target set is dynamically optimized accordingly. When a decrease in the actual occupied CCE is detected, the interference range is automatically reduced; when a new occupied CCE is detected, it is promptly added to the interference set. This closed-loop adjustment strategy further reduces the average interference transmit power while ensuring the shielding effect, achieving "dynamic interference on demand," avoiding ineffective energy consumption of unused resources, and improving the energy efficiency ratio of the equipment.

[0019] The technical framework is independent of custom specifications. By mapping the PCFICH / PDCCH interference strategy in the LTE system to the interference strategy for candidate positions in the Type 0-PDCCH CSS and CORESET in the NR system, and combining it with an equally applicable dynamic energy detection adjustment mechanism, compatibility with both 4G LTE and 5G NR systems is achieved. This ensures the continued effectiveness of the shielding equipment during the evolution of operator networks and extends the equipment's technical lifecycle.

[0020] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the 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 based on these drawings without creative effort.

[0022] Figure 1 This paper presents a schematic diagram of the process for shielding on-network users in a cellular network based on multi-level precise interference, as provided in this application. Figure 2 The diagram illustrates the architecture of the cellular network user shielding system based on multi-level precise interference provided in this application. Detailed Implementation

[0023] 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.

[0024] Example 1 This application provides a method for blocking on-network users in cellular networks based on multi-level precise interference, such as... Figure 1 ,include: Scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; Based on the physical layer cell identifier and system bandwidth, calculate the fixed time-frequency position of the physical control format indicator channel and transmit the first-level interference signal; Calculate the candidate location set of the physical downlink control channel, the candidate location set including candidate locations in the common search space and estimated locations in the user-dedicated search space, and transmit a second-level interference signal on the time-frequency resources corresponding to the candidate location set; During the parallel transmission of the first-level and second-level interference signals, a periodic measurement window is reserved. Within the measurement window, interference transmission is turned off and fast energy detection is performed to identify the control channel units that are actually occupied. The candidate position set is then dynamically adjusted based on the detection results.

[0025] The Physical Control Format Indicator Channel (PCFICH) is used to indicate the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols occupied by the control region in a subframe (control format indicator (CFI value), which is 1, 2 or 3), and the position of the Physical Control Format Indicator Channel is fixed.

[0026] Optionally, the step of calculating the fixed time-frequency position of the physical control format indication channel and transmitting the first-level interference signal based on the physical layer cell identifier and system bandwidth includes: According to the 3GPP TS 36.211 protocol, the frequency domain positions of the four resource unit groups are determined by the physical layer cell identifier and the system bandwidth, and the four resource unit groups are evenly distributed across the entire system bandwidth. During the first orthogonal frequency division multiplexing symbol of each subframe, jamming signals are transmitted at the locations of the four resource element groups.

[0027] The first-level interference signal is emitted, preventing the terminal from correctly decoding the CFI value, thereby affecting its judgment of the size of the control area.

[0028] Since user equipment (UE) may cache historical CFI values ​​or attempt blind detection, relying solely on PCFICH interference may have shielding vulnerabilities, requiring a second level of interference as a supplement.

[0029] The Physical Downlink Control Channel (PDCCH) is carried within the control area via Control Channel Elements (CCEs). Its possible location is determined by the search space, including the Common Search Space (CSS) and the User Private Search Space (USS). According to the 3GPP TS36.213 protocol: CSS position calculation: CSS is used to carry public control information such as system information and paging, and its position is fixed.

[0030] USS Location Range Assessment: The USS is used to carry user-specific scheduling information, and its location is dynamically determined by the user's RNTI using a hash function. Although the specific user's RNTI cannot be predicted, the possible distribution range of the USS can be assessed: typically, the USS occupies the middle part of the CCE index within the control area (e.g., 30%-80% of the area).

[0031] Optionally, the set of candidate locations for calculating the physical downlink control channel includes: Calculate candidate positions with aggregation levels of 4 and 8 in the common search space, the candidate positions being determined by the initial... It consists of an index and L consecutive control channel units, the starting... The index is determined based on the following formula:

[0032] Where L represents the aggregation level, Indicates the starting position, with a value of 0. =0 indicates a fixed starting position, always starting from CCE 0, ensuring a fixed and consistent starting position for all UEs. k represents the subframe index, and m represents the candidate index. Indicates the total number of control channel elements available in the current subframe; The distribution range of the user-dedicated search space is assessed, and the location is dynamically determined by the user's temporary radio network identifier (RNTI) through a hash function, taking the area within the control zone. The middle preset ratio area of ​​the index serves as the estimated location of the user's dedicated search space; The candidate locations in the public search space are combined with the estimated locations in the user-specific search space to form the candidate location set.

[0033] During each OFDM symbol in the control area, interference signals are transmitted to the time-frequency resources corresponding to these CCEs.

[0034] Compared to full-bandwidth suppression, this method only interferes with a portion of the CCE, significantly reducing interference bandwidth and power consumption. Because it covers all possible PDCCH locations, it ensures that the PDCCH of all users on the network is interfered with.

[0035] Optionally, the periodically reserved measurement window includes: Every N subframes, the last few orthogonal frequency division multiplexing symbols of the last subframe are reserved as a measurement window, where N is a configurable positive integer.

[0036] Optionally, performing fast energy detection includes: During the intervals between jamming transmissions (e.g., reserving a measurement window every N subframes), scan all control channel elements (CCEs) within the control area; Measure the received power of each control channel unit (CCE) and set an adaptive threshold (e.g., background noise power + 3dB, which can be configured). Control channel units (CCEs) whose received power exceeds the adaptive threshold are identified as actually occupied control channel units (CCEs).

[0037] Optionally, the dynamic adjustment includes: Compare the actually occupied control channel units with the current set of candidate locations; If more than a first preset proportion (e.g., more than 10%, the specific value can be configured) of the actually occupied control channel units are not in the current candidate location set, then the candidate location set is expanded and the newly occupied control channel units are added to the interference target; If more than a second preset proportion (e.g., exceeding 30%, the specific value can be configured) of control channel units in the current candidate location set are not actually occupied, then the candidate location set is reduced, unoccupied control channel units are removed, and a preset margin is retained.

[0038] The adjusted interference set is used as the interference target in subsequent subframes to achieve adaptive optimization.

[0039] Optionally, the first-level interference signal and the second-level interference signal are synchronized with the target cell frame timing, transmitted during the downlink subframe, and the transmission power is higher than the target cell reference signal power by a specific offset.

[0040] Overall Implementation Process Initialization phase: After the device starts up, it scans surrounding base stations to obtain parameters such as the target cell's PCI and system bandwidth; Level 1 interference initiation: Calculate the fixed position of PCFICH based on PCI and bandwidth, and perform interference on the first symbol of each subframe; Level 2 interference configuration: Calculate the control area size (which can be decoded by PCFICH or a preset value), determine the number of available CCEs, calculate CSS candidate locations, evaluate possible USS areas, and generate an initial set of interference CCEs; Real-time jamming execution: In the control area of ​​each subframe, jamming signals are transmitted to the fixed position of PCFICH and the candidate position of PDCCH; Periodic energy detection and adjustment: Perform rapid energy detection according to a preset period, and dynamically adjust the CCE set of PDCCH interference based on the detection results; Continuous optimization: Through closed-loop adjustments, unnecessary interference is gradually reduced and power consumption is lowered while ensuring the shielding effect.

[0041] Implementation example (LTE system): Assume the target cell is an LTE FDD with a bandwidth of 20MHz and PCI=125.

[0042] 1. PCFICH Interference Implementation According to the 3GPP TS 36.211 protocol, calculate the four REG positions of PCFICH: The system bandwidth of 20MHz corresponds to 100 resource blocks (RBs); Calculate the starting REG index: k = (100 / 2) × (125 mod (2×100)) mod (2×100); The four REG indices are calculated sequentially and mapped to the time-frequency resource grid.

[0043] During the first OFDM symbol of each subframe, interference signals (such as QPSK modulated random sequences) are transmitted at the four REG positions mentioned above.

[0044] 2. PDCCH Candidate Location Interference Implementation By decoding PCFICH to obtain the CFI value (assuming it is 2), the control area is determined to be 2 OFDM symbols; Calculate the total number of available CCEs N_CCE(k): k is the subframe index. After considering the overhead of reference signals, PHICH, etc., N_CCE(k) is approximately 80. Calculate CSS candidate positions: L=4: 4 candidates, with initial CCE indices of 0, 4, 8, 12 (assuming N_CCE(k) is large enough); L=8: 2 candidates, with initial CCE indices of 0 and 8 respectively; Assess the possible USS area: Take CCE index 30 to 60 as the possible range of the USS; Merge the set of interfering CCEs: including CSS candidate CCEs and all CCEs within the USS scope; During the first two OFDM symbols of each subframe, interference signals are transmitted to the time-frequency resources corresponding to the aforementioned CCE.

[0045] 3. Rapid Energy Detection and Adjustment Implementation In every 10 subframes, the last few symbols of the 10th subframe are reserved as a measurement window; Within the measurement window, with interference transmission turned off, quickly measure the received power of each CCE; Set threshold: Calculate the median of all CCE power as background noise, threshold = median + 3dB (3dB is just an example, and can be configured accordingly). Identify occupied CCEs: CCEs with power exceeding the threshold are marked as occupied; Comparison and Adjustment: Assume the current interference set contains 50 CCEs, and 30 are detected to be actually occupied, of which 5 are not in the current set; Expanding the interference set: Add 5 new CCEs to the set, bringing the total number of interference sets to 55. At the same time, check if there are a large number of unoccupied CCEs in the current set, and remove them appropriately if necessary.

[0046] Update the interference targets in subsequent subframes.

[0047] Implementation example (NR system): Assume the target cell is a 5G NR FDD system with a carrier bandwidth of 100MHz (subcarrier spacing SCS=30kHz, μ=1) and physical layer cell identifier PCI=100.

[0048] Level 1 Interference: Interference with Critical Public Control Information (corresponding to the CFI bearer mechanism in NR) In NR systems, there is no PCFICH channel exactly the same as in LTE (there is no PCFICH in NR). The time-domain length (i.e., the number of OFDM symbols, 1 to 3 symbols) and search space configuration of the control resource set (CORESET) are semi-statically configured by higher-layer signaling (such as MIB, SIB1). The number of CORESET symbols actually used for PDCCH monitoring within a subframe (or time slot) is dynamically indicated by the "time-domain resource allocation" contained in the "frequency domain resource allocation" field of the downlink control information (DCI).

[0049] Interference Target Selection: The DCI format 1_0 carrying the system information (RMSI) scheduling information is selected as the first-level core interference target. This DCI is sent through the Type0-PDCCH common search space (CSS set), and its position is determined by the pdcch-ConfigSIB1 field in the PBCH, which is relatively fixed.

[0050] Interference methods: Initialization: After the device is powered on, it listens to and decodes the SSB (synchronization signal and PBCH block) of the target cell, and obtains the configuration information of CORESET#0 (the common CORESET used for initial access) in the PCI and MIB, including the time and frequency domain position, number of symbols, etc.

[0051] Location Calculation: Based on the 3GPP TS 38.213 protocol and the PCI and CORESET#0 configuration, the monitoring timing and candidate PDCCH locations for Type0-PDCCH CSS are calculated. The location of this search space is fixed on a timescale of at least tens of milliseconds.

[0052] Interference Implementation: During the calculated Type0-PDCCH CSS monitoring time (specific time slots and symbols), interference signals are transmitted in the corresponding CORESET#0 resource unit for all PDCCH candidate positions at all aggregation levels (ALs) within that CSS. This prevents the terminal from correctly decoding the DCI of scheduling SIB1, thereby blocking its path to obtain critical system information and establish RRC connections.

[0053] Second-level interference: PDCCH candidate position interference In NR, PDCCH transmission is based on a combination of CORESET and Search Space. The interference principle remains to cover all PDCCH candidates that may carry valid DCI.

[0054] Interference target identified: Common Search Space (CSS): This includes the Type 0 / 0A / 1 / 2 / 3-PDCCH CSSs. The locations of these search spaces can be obtained by decoding the MIB and SIB1, or calculated based on protocol specifications and PCI (such as Type 0-PDCCH). They are the necessary pathways for terminals to receive public information such as paging, random access responses, and uplink authorizations, and must be included in the interference set.

[0055] User-Dedicated Search Space (USS): The USS is configured individually for each UE by RRC signaling and cannot be known in advance. However, the USS is always configured within a pre-configured CORESET (which may be CORESET#0 or another dedicated CORESET).

[0056] Interference methods: Step 1: By listening, try to obtain the CORESET configuration (besides CORESET#0, there may be other indexed CORESETs) and associated CSS configurations broadcast by the target cell.

[0057] Step 2: For each identified CORESET, calculate the PDCCH candidate positions for all CSSs configured within it (based on a hash function according to the 3GPP TS 38.213 protocol).

[0058] Step 3: For the USS, adopt a strategy that covers the entire potential area of ​​the CORESET. Since all CCEs (or REG bundles) within a CORESET may be assigned to the USS, all resources within that CORESET, except for the specific CCE set already identified for CSS, are evaluated as potential areas of the USS and added to the set to be interfered with.

[0059] Step 4: At each PDCCH monitoring time (defined by the monitoringSlotPeriodicityAndOffset and monitoringSymbolsWithinSlot parameters of the search space), transmit interference signals to the time-frequency resources corresponding to the above merged set of "CSS candidates + other resources in CORESET".

[0060] Level 3 Interference: Rapid Energy Detection and Dynamic Adjustment This level of logic is highly common to LTE implementations; the only difference is that the object is replaced with "CCE" instead of "CCE / REG bundle set within CORESET".

[0061] Fast power detection method: During a preset interference interval (e.g., every 20 time slots), turn off interference transmission, quickly scan all resource elements (REs) within all identified CORESETs, and measure the received power.

[0062] Dynamic adjustment strategy: Identify actual occupancy: Based on the energy of each CCE / REG bundle area, set an adaptive threshold (such as global median + 3dB) to identify candidate locations where the base station actually transmitted PDCCH during the current monitoring period.

[0063] Set adjustment: If more than a certain percentage (e.g., 10%, the specific value can be configured) of the candidate positions actually occupied are not in the current interference set, then they are added to the interference set. This could be a newly configured USS or an unrecognized CSS.

[0064] If the current interference set is consistently much larger than (e.g., exceeding 50%, the specific value can be configured) the actual detected occupied set, then gradually reduce the interference range. For example, revert from "covering the entire CORESET" to "covering CSS candidates + recently detected USS candidates".

[0065] Optimization objective: Through learning and adaptation, make the perturbation set approximate the optimal set of "all CSS candidates + currently active USS candidates", maximizing perturbation efficiency and minimizing unnecessary energy emission.

[0066] Example 2 Based on the same inventive concept, this application also provides a cellular network user shielding system based on multi-level precise interference, such as... Figure 2 ,include: The scanning unit is used to scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; The first interference unit is used to calculate the fixed time-frequency position of the physical control format indication channel based on the physical layer cell identifier and system bandwidth, and to transmit the first-level interference signal. The second jamming unit is used to calculate the candidate position set of the physical downlink control channel, the candidate position set including candidate positions in the common search space and estimated positions in the user-dedicated search space, and to transmit a second-level jamming signal on the time-frequency resources corresponding to the candidate position set. The detection and adjustment unit is used to reserve a periodic measurement window during the parallel transmission of the first-level interference signal and the second-level interference signal, shut down the interference transmission and perform fast energy detection within the measurement window, identify the control channel units that are actually occupied, and dynamically adjust the candidate position set according to the detection results.

[0067] Optionally, the system further includes a synchronization module for synchronizing the first-level interference signal and the second-level interference signal with the target cell frame at a specific time, transmitting them during downlink subframes, and transmitting them at a power higher than the target cell reference signal power by a specific offset.

[0068] Example 3 Based on the same inventive concept, this application also provides an electronic device. The electronic device of this application includes at least one processor and at least one storage medium electrically connected to the processor. The storage medium is electrically connected to the processor, wherein the storage medium stores instructions executable by the at least one processor, which, when executed by the at least one processor, enables the at least one processor to perform the method described above.

[0069] Example 4 Based on the same inventive concept, this application also provides a storage medium storing instructions executable by at least one processor, the instructions being executed by at least one processor to enable at least one processor to perform the method described above.

[0070] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for shielding on-network users in a cellular network based on multi-level precise interference, characterized in that, include: Scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; Based on the physical layer cell identifier and system bandwidth, calculate the fixed time-frequency position of the physical control format indicator channel and transmit the first-level interference signal; Calculate the candidate location set of the physical downlink control channel, the candidate location set including candidate locations in the common search space and estimated locations in the user-dedicated search space, and transmit a second-level interference signal on the time-frequency resources corresponding to the candidate location set; During the parallel transmission of the first-level and second-level interference signals, a periodic measurement window is reserved. Within the measurement window, interference transmission is turned off and fast energy detection is performed to identify the control channel units that are actually occupied. The candidate position set is then dynamically adjusted based on the detection results.

2. The method according to claim 1, characterized in that, The step of calculating the fixed time-frequency position of the physical control format indication channel and transmitting the first-level interference signal based on the physical layer cell identifier and system bandwidth includes: According to the LTE physical layer protocol, the frequency domain location of the resource unit group is determined by the physical layer cell identifier and the system bandwidth, and the resource unit group is evenly distributed across the entire system bandwidth. During the first orthogonal frequency division multiplexing symbol of each subframe, an interference signal is transmitted at the location of the resource unit group.

3. The method according to claim 1, characterized in that, The set of candidate locations for calculating the physical downlink control channel includes: Calculate candidate locations in the common search space, the candidate locations being determined by the starting point. It consists of an index and L consecutive control channel units, the starting... The index is determined based on the following formula: Where L represents the aggregation level, Indicates the starting position, k represents the subframe index, and m represents the candidate index. Indicates the total number of control channel elements available in the current subframe; The distribution range of the user-specific search space is assessed, and the location is dynamically determined by the user RNTI using a hash function, taking the area within the control region. The middle preset ratio area of ​​the index serves as the estimated location of the user's dedicated search space; The candidate locations in the public search space are combined with the estimated locations in the user-specific search space to form the candidate location set.

4. The method according to claim 1, characterized in that, The periodically reserved measurement window includes: Every N subframes, the last few orthogonal frequency division multiplexing symbols of the last subframe are reserved as a measurement window, where N is a configurable positive integer.

5. The method according to claim 1, characterized in that, The process of performing fast energy detection includes: Scan all control channel units (CCEs) within the control area; Measure the received power of each control channel element (CCE) and set an adaptive threshold; Control channel units (CCEs) whose received power exceeds the adaptive threshold are identified as actually occupied control channel units (CCEs).

6. The method according to claim 1, characterized in that, The dynamic adjustment includes: Compare the actually occupied control channel units with the current set of candidate locations; If more than a first preset proportion of the control channel units actually occupied are not in the current candidate location set, then the candidate location set is expanded and the newly occupied control channel units are added to the interference target. If more than a second preset proportion of control channel units in the current candidate location set are not actually occupied, then the candidate location set is reduced, unoccupied control channel units are removed, and a preset margin is retained.

7. The method according to claim 1, characterized in that, The first-level interference signal and the second-level interference signal are synchronized with the target cell frame timing, transmitted during the downlink subframe, and the transmission power is higher than the target cell reference signal power by a specific offset.

8. A cellular network user shielding system based on multi-level precise interference, characterized in that, include: The scanning unit is used to scan surrounding base stations to obtain the physical layer cell identifier and system bandwidth of the target cell; The first interference unit is used to calculate the fixed time-frequency position of the physical control format indication channel and transmit the first-level interference signal based on the physical layer cell identifier and system bandwidth. The second jamming unit is used to calculate the candidate position set of the physical downlink control channel, the candidate position set including candidate positions in the common search space and estimated positions in the user-dedicated search space, and to transmit a second-level jamming signal on the time-frequency resources corresponding to the candidate position set. The detection and adjustment unit is used to reserve a periodic measurement window during the parallel transmission of the first-level interference signal and the second-level interference signal, shut down the interference transmission and perform fast energy detection within the measurement window, identify the control channel units that are actually occupied, and dynamically adjust the candidate position set according to the detection results.

9. The system according to claim 8, characterized in that, The system also includes a synchronization module for synchronizing the first-level interference signal and the second-level interference signal with the target cell frame at a specific time, transmitting them during downlink subframes, and transmitting them at a power higher than the target cell reference signal power by a specific offset.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method for blocking on-network users in a cellular network based on multi-level precise interference as described in any one of claims 1-7.

11. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; When a processor executes a program stored in a memory, it implements the steps of the method for masking on-network users in a cellular network based on multi-level precise interference as described in any one of claims 1-7.

Images