5G network anti-interference test method and system based on radio frequency coverage interference

Abstract

The invention discloses a 5G network interference test method and system based on radio frequency coverage interference. The system comprises legal transmitting equipment, receiving equipment to be tested and radio frequency interference equipment, the radio frequency interference device implements various different types of interference, including but not limited to persistent interference, reactive interference, random / periodic interference, synchronous radio frequency coverage interference, and the like. According to the invention, radio frequency coverage interference, including time-frequency synchronization, interference subframe generation and interference subframe transmission, is realized. The legal transmitting device and the receiving device to be tested for the anti-interference test collect and store performance indexes of the 5G network system in an interference environment, such as a signal-to-noise ratio, a block error rate, a data rate and the like. According to the invention, the limit anti-interference performance of the 5G equipment is evaluated by using the radio frequency coverage interference, the provided interference means has advancement, the targeted interference suffered by the 5G equipment in a real scene can be simulated, and the anti-interference performance of the equipment under the novel radio frequency coverage interference is tested.

Description

Technical Field

[0001] The present invention relates to the fields of wireless communication technology and wireless network security, and specifically to a 5G network anti-interference testing method and system based on radio frequency coverage interference. Background Art

[0002] At present, cellular mobile communication technology has been widely used and has penetrated into all aspects of social production and people's lives. The fifth generation of mobile communication technology (5th Generation Mobile Networks, referred to as 5G or 5G technology) is the latest generation of cellular mobile communication technology, and is also an extension of 2G (GSM), 3G (UMTS) and 4G (LTE) systems. The performance goals of 5G are high data rate, reduced latency, energy saving, reduced cost, increased system capacity and large-scale device connection. Anti-interference is one of the important characteristics of 5G networks, which ensures the reliability and performance of the network. However, in actual deployment and application, 5G devices will face various interference sources, including but not limited to signal interference from other wireless devices, and even malicious attackers will specifically interfere with the target device. These interferences may cause signal attenuation, transmission errors, connection interruptions and other problems, which in turn affect the user's communication quality and experience. Therefore, it is crucial for 5G devices to have good anti-interference. By testing the anti-interference performance of the equipment, interference problems can be identified and solved, the design and algorithm of the equipment can be improved, and the robustness and reliability of the network can be improved.

[0003] The radio frequency coverage interference technology can be used to test the anti-interference performance limit of wireless communication networks. Among the interferences to 5G wireless communication networks, the first thing to be mentioned is the traditional jammer. With sufficient output power, traditional jammers can always achieve the purpose of interfering with communications by emitting noise. However, the use of traditional noise jammers usually requires high-cost, high-energy hardware, and the range of influence is usually small, and the interference behavior is easier to detect.

[0004] The radio frequency coverage interference that the present invention relies on is a targeted interference technology that has the potential to achieve lower power and higher concealment. Summary of the invention

[0005] In order to better test the anti-interference performance of 5G networks, the present invention proposes a 5G network anti-interference test method and system based on radio frequency coverage interference. Relying on radio frequency coverage interference technology, it can not only achieve effective interference effect with lower power, but also perform tests without being easily detected, which opens up a new way to accurately evaluate the anti-interference capability of 5G networks, optimize equipment design and algorithms, and further improve the robustness and reliability of the network.

[0006] The technical solution of the present invention is as follows:

[0007] On the one hand, the present invention provides a 5G network interference testing method based on radio frequency coverage interference, which is characterized in that it includes the following steps:

[0008] Step 1. Start the legal transmitting device, configure the transmission parameters, including transmission gain, transmission frequency band, ARFCN, subcarrier spacing, channel bandwidth, cyclic prefix, physical cell ID, and continuously transmit downlink broadcast signals and synchronization signals;

[0009] Step 2. Start the receiving device to be tested, configure the receiving parameters, including receiving gain, receiving frequency band, ARFCN, sampling rate, APN, and perform the initial random access process, and finally establish a connection with the legal transmitting device;

[0010] Step 3. Under normal communication environment, the receiving device collects communication quality indicators, including signal-to-noise ratio, block error rate, and data rate, as baseline indicators;

[0011] Step 4. Start the RF jammer and perform time and frequency synchronization by receiving the synchronization signal from the legal transmitting device;

[0012] Step 5. The RF interference device calculates the exact time of transmitting the interference subframe according to the information obtained in step 4, and transmits the coverage interference signal at the specific subframe time;

[0013] Step 6. In an interference communication environment, the receiving device collects communication indicators, including signal-to-noise ratio, block error rate, and data rate, and compares and analyzes them with the baseline indicators obtained in step 3 to obtain the anti-interference performance of the receiving device under radio frequency coverage interference;

[0014] Step 7. Analyze the interference effect, adjust the interference parameters according to the interference test results, and conduct further tests. After each test, step 2 needs to be re-executed to start the receiving device to be tested, or the receiving device to be tested is started when the interference is performed to test the impact of the interference on the normal startup and initial access of the receiving device.

[0015] Furthermore, in step 4, the radio frequency interference device is started to synchronize time and frequency with the legal transmitting device. The specific steps are as follows:

[0016] The radio frequency coverage jammer receives the synchronization sequence transmitted by the legal transmitting device for synchronization sequence detection;

[0017] Calculate the cross-correlation between the received sequence and the standard synchronization sequence, convert the synchronization sequence from the time domain to the frequency domain through discrete Fourier transform, multiply the two in the frequency domain, and then inversely transform to the time domain to obtain the cross-correlation result;

[0018] According to the cross-correlation result, the subscript k0 of the peak value is found and determined as the starting point of the synchronization sequence in the actual received sample, and preliminary synchronization is achieved with the frame;

[0019] Get the precise location of the synchronization signal block (SSB) to obtain the subframe timing and physical cell ID in the SSB;

[0020] The current frame number is read from the master information block (MIB) and the information of the frame and subframe sequence is obtained.

[0021] Further, in step 5, the accurate time of transmitting the interference subframe is calculated according to the acquired information, and the covering interference signal is transmitted at the specific subframe time. The specific steps are as follows:

[0022] Generate interference signal subframe: For the target subframe, tamper with specific key fields, and then perform the corresponding encoding process to generate interference subframe;

[0023] Calculate the time T of transmitting the interference signal subframe tx =T rx +T offset -T adv , where T rx is the current time, T offset is the offset of the target subframe to the current time, T adv =n adv / srate is the time for software and hardware sampling advance;

[0024] An interference signal subframe synchronized with the legal transmitting device is transmitted at a specific subframe time with a power slightly higher than that of the legal transmitting device.

[0025] On the other hand, the present invention also provides a 5G network interference test system based on radio frequency coverage interference, characterized in that it includes:

[0026] Legal transmitting equipment, used to configure transmission parameters and continuously transmit downlink broadcast signals and synchronization signals;

[0027] The receiving device to be tested is used to configure receiving parameters and perform the initial random access process, and finally establish a connection with the legal transmitting device;

[0028] Radio frequency interference equipment, used to receive the synchronization signal of the legal transmitting equipment to perform time and frequency synchronization, calculate the exact time of transmitting the interference subframe based on the synchronization information, and transmit the covering interference signal at a specific subframe time;

[0029] Among them, the radio frequency interference device is synchronized with the legal transmitting device, and can transmit interference signal subframes at a power slightly higher than that of the legal transmitting device at a specific subframe time. The receiving device to be tested is used to collect communication quality indicators under normal communication environment and interference environment, and perform comparative analysis to obtain anti-interference performance.

[0030] Furthermore, the radio frequency interference device also includes a module for calculating the cross-correlation between the received sequence and the standard synchronization sequence, which module realizes the conversion from time domain to frequency domain through discrete Fourier transform, and then inversely transforms to time domain to obtain the cross-correlation result.

[0031] Furthermore, the radio frequency interference device also includes a module for generating an interference signal subframe, and the module generates the interference signal subframe by tampering with a specific key field of the target subframe and performing a corresponding encoding process.

[0032] The present invention is also compatible with a variety of conventional interferences, including traditional continuous interference, reactive interference, periodic interference, etc., for more comprehensive interference testing. By replacing steps 4 to 5 with conventional interference means, the anti-interference performance of the device under conventional interference can be tested.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1) A new 5G interference test system architecture based on software defined radio technology (SDR) is proposed. The system architecture integrates legal transmitting equipment (5G base station), receiving equipment to be tested (5G user equipment) and radio frequency interference equipment, and realizes flexible communication and interference testing between users, base stations and core networks in a software-driven manner. Traditional 5G interference test systems often rely on fixed configurations of hardware equipment and lack flexibility and scalability. The present invention introduces SDR technology to enable the system to be flexibly configured and reconstructed at the software level according to different test requirements, thereby significantly improving the test efficiency and accuracy. The interference means provided by the system of the present invention are advanced and can simulate the targeted interference of 5G devices in real scenarios, and test the anti-interference performance of equipment under new radio frequency coverage interference. The radio frequency interference equipment demodulates the unencrypted public channels (synchronization signals, broadcast channels, etc.) of the base station to achieve precise alignment of sampling points and frequencies with the base station, and obtain the time information (frame number, subframe number, etc.) of the base station. Since the broadcast channel has no integrity protection, the coverage interference end can tamper with a specific broadcast channel subframe, and the original signal can be covered by only a slight increase in the transmission power.

[0035] 2) The time and frequency synchronization method between the RF interference equipment and the legal transmitting equipment is adopted. By receiving the synchronization signal of the legal transmitting equipment and using mathematical tools such as discrete Fourier transform to perform cross-correlation calculations, the synchronization signal is analyzed and processed, thereby achieving accurate synchronization and improving the accuracy and stability of synchronization.

[0036] 3) By adopting the interference signal subframe generation and transmission method, by tampering with the specific key fields of the legitimate transmitting device (such as 5G MIB key bits) and executing the corresponding encoding process, an interference signal subframe that is synchronized with the legitimate signal but with tampered content is generated. This can more realistically simulate the interference situation in the actual communication environment, thereby significantly improving the accuracy and practicality of the test.

[0037] 4) It not only supports the test method based on RF coverage interference, but also is compatible with a variety of conventional interference (such as continuous interference, reactive interference, periodic interference, etc.) for more comprehensive interference testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is an operation flow chart of the 5G interference test system based on radio frequency coverage interference of the present invention.

[0039] Figure 2 This is a schematic diagram of radio frequency coverage interference. DETAILED DESCRIPTION

[0040] The present invention will be further explained below in conjunction with the accompanying drawings and embodiments, but the protection scope of the present invention should not be limited thereto.

[0041] The present embodiment is a 5G interference test method and system based on radio frequency coverage interference, which is intended to evaluate the anti-interference performance of 5G user equipment (UE) in an interference environment by simulating radio frequency interference. The entire system consists of three types of core equipment: a legal transmitting device (i.e., a 5G base station), a receiving device to be tested (i.e., a 5G user equipment), and a radio frequency interference device. In a 5G network platform based on software-defined radio technology, users are connected to base stations wirelessly, base stations are connected to the core network by wire, and the core network is connected to the Internet. The three devices in the system, namely users, base stations, and core networks, are all software-driven and can run on an operating system based on the Linux kernel. Signals are sent and received between users and base stations through wireless radio frequency equipment, which is implemented using third-party platforms such as USRP. The following is a detailed explanation of each step and key technology:

[0042] The system includes:

[0043] Legal transmitting equipment: As a 5G base station, it is responsible for transmitting downlink broadcast signals and synchronization signals so that user devices can access the network.

[0044] Receiver under test: As a 5G user device, it is responsible for receiving signals from the base station and evaluating its communication quality in normal and interference environments.

[0045] Radio frequency interference equipment: responsible for simulating radio frequency interference, synchronizing time and frequency with the base station, and transmitting interference signals at specific times.

[0046] A 5G interference testing method based on radio frequency coverage interference includes the following steps:

[0047] Step 1. Start the legal transmitting equipment (usually a 5G base station).

[0048] (1-1) Configure the parameters of the transmitting equipment, including transmission gain (70dB), transmission frequency band, ARFCN (band 3, 368500), subcarrier spacing (15kHz), channel bandwidth (10MHz), cyclic prefix, physical cell ID and other key information.

[0049] (1-2) The transmitting device reads the configuration and starts, continuously transmitting downlink broadcast signals and synchronization signals.

[0050] Step 2. Start the receiving device to be tested (usually a 5G terminal device).

[0051] (2-1) The receiving device performs parameter configuration, including receiving gain (70dB), receiving frequency band, ARFCN (band 3, 368500), sampling rate (11.52MHz), USIM related parameters (K, OPC, IMSI, IMEI, etc.), APN and other key information.

[0052] (2-2) The receiving device reads the configuration and starts. Under normal circumstances, the receiving end begins the initial random access process and eventually establishes a connection with the transmitting device.

[0053] Step 3. The receiving device under test collects communication quality indicators under normal communication environment, including signal-to-noise ratio, block error rate, data rate, etc., as baseline indicators.

[0054] Step 4. Start the RF jammer and synchronize the time and frequency with the legal transmitter. The specific steps are as follows:

[0055] (4-1) The radio frequency coverage jammer receives the synchronization signal y[n] transmitted by the legitimate transmitting device for synchronization sequence detection;

[0056] (4-2) Calculate the cross-correlation between the received sequence and the standard synchronization sequence. Use discrete Fourier transform to convert the synchronization sequence from the time domain y[n] to the frequency domain Y[f] = FFT(y[n]). Let the time domain synchronization sequence with the root sequence index u be s u [n], converted to the frequency domain S using discrete Fourier transform u [f] = FFT(s u [n]). The conjugate cross-correlation of the signal sample offset k with the standard synchronization sequence can be written as (N is the sequence length), which is the multiplication of the two in the frequency domain. Then, the cross-correlation z[k]=IFFT(Z[f]) can be obtained by inverse transforming to the time domain.

[0057] (4-3) Find the subscript k0 that gets the peak value in all the cross-correlations z[k], which is the starting point of the synchronization sequence in the actual received sample. In this way, the required preliminary synchronization information is obtained and preliminary synchronization with the frame is achieved.

[0058] (4-4) After successfully synchronizing the frame timing through synchronization sequence detection, the precise position of the synchronization signal block (SSB) can be obtained, thereby obtaining the subframe timing and physical cell ID in the SSB.

[0059] (4-5) Read the current frame number from the master information block (MIB) and further obtain information about the frame and subframe sequence, such as subCarrierSpacingCommon, dmrs-TypeA-Position, pdcch-ConfigSIB1, cellBarred and other system information parameters.

[0060] Step 5. The RF interference device calculates the exact time to transmit the interference subframe based on the synchronization information obtained in step 4, and transmits the coverage interference signal at the specific subframe time. The specific steps are as follows:

[0061] (5-1) Generate an interference signal subframe. For the target subframe, tamper with a specific key field, and then perform the corresponding encoding process to generate an interference subframe. In this embodiment, the RF interference device tampers with the 5G MIB key bits of the base station (such as cellBarred or infraFreqResselection), or modifies pchch-ConfigSib1, and performs the corresponding PBCH encoding process.

[0062] (5-2) Calculate the exact time T of transmitting the interference signal subframe tx =T rx +T ofset -T adv , T rx is the current time, T offset is the offset of the target subframe to the current time. Usually, the target subframe is the current subframe of the next frame, that is, 10ms. adv =n adv / srate, corresponding to the time of the software and hardware sampling advance, is the number of symbols of the advance (66 in this embodiment) divided by the sampling rate (11.52 MHz), which is equal to 5.729 μs.

[0063] (5-3) The RF interference device transmits an interference signal subframe synchronized with the legal transmitting device at a specific subframe time with a power slightly higher than that of the legal transmitting device by about 3 dB, that is, the PBCH symbol generated in step 5-1.

[0064] Step 6. The receiving device under test collects communication indicators under interference, including signal-to-noise ratio, block error rate, data rate, etc. Compare and analyze with the baseline indicators of the normal communication environment to obtain the anti-interference performance of the receiving device under RF coverage interference.

[0065] Step 7. Analyze the interference effect and adjust the interference parameters according to the interference test results, such as the power of the RF interference, the tampered bit field, etc., for further testing. After each test, you need to re-execute step 2 to start the receiver under test for the next test. You can also start the receiver under test when the interference is executed to test whether the interference affects the normal startup and initial access of the receiver. You can optionally re-execute step 1 before re-executing step 2.

[0066] The present invention is also compatible with a variety of conventional interferences, including traditional continuous interference, reactive interference, periodic interference, etc., for more comprehensive interference testing. By replacing steps 4 to 5 with conventional interference means, the anti-interference performance of the device under conventional interference can be tested.

[0067] Finally, the results of a series of tests previously conducted are evaluated to obtain the anti-interference performance of the receiving device under RF coverage interference and conventional interference.

[0068] The present invention provides an efficient and flexible 5G interference testing method and system, which can comprehensively evaluate the anti-interference performance of 5G user equipment in an interference environment, and provide strong support for the optimization and upgrading of 5G networks.

Claims

1. A 5G network interference test method based on radio frequency coverage interference, characterized in that: The following steps are involved: Step 1. Start the legal transmitting device, configure the transmission parameters, including transmission gain, transmission frequency band, ARFCN, subcarrier spacing, channel bandwidth, cyclic prefix, physical cell ID, and continuously transmit downlink broadcast signals and synchronization signals; Step 2. Start the receiving device to be tested, configure the receiving parameters, including receiving gain, receiving frequency band, ARFCN, sampling rate, APN, and perform the initial random access process, and finally establish a connection with the legal transmitting device; Step 3. Under normal communication environment, the receiving device collects communication quality indicators, including signal-to-noise ratio, block error rate, and data rate, as baseline indicators; Step 4. Start the RF jammer and perform time and frequency synchronization by receiving the synchronization signal from the legal transmitting device; Step 5. The RF interference device calculates the exact time of transmitting the interference subframe according to the information obtained in step 4, and transmits the coverage interference signal at the specific subframe time; Step 6. In an interference communication environment, the receiving device collects communication indicators, including signal-to-noise ratio, block error rate, and data rate, and compares and analyzes them with the baseline indicators obtained in step 3 to obtain the anti-interference performance of the receiving device under radio frequency coverage interference; Step 7. Analyze the interference effect, adjust the interference parameters according to the interference test results, and conduct further tests. After each test, step 2 needs to be re-executed to start the receiving device to be tested, or the receiving device to be tested is started when the interference is performed to test the impact of the interference on the normal startup and initial access of the receiving device.

2. The 5G network interference testing method based on radio frequency coverage interference according to claim 1 is characterized in that: In step 4, the radio frequency interference device is started to synchronize time and frequency with the legal transmitting device. The specific steps are as follows: The radio frequency coverage jammer receives the synchronization sequence transmitted by the legal transmitting device for synchronization sequence detection; Calculate the cross-correlation between the received sequence and the standard synchronization sequence, convert the synchronization sequence from the time domain to the frequency domain through discrete Fourier transform, and then inversely transform it to the time domain to obtain the cross-correlation result; According to the cross-correlation result, the subscript k0 of the peak value is found and determined as the starting point of the synchronization sequence in the actual received sample, and preliminary synchronization is achieved with the frame; Get the precise location of the synchronization signal block (SSB) to obtain the subframe timing and physical cell ID in the SSB; The current frame number is read from the master information block (MIB) and the information of the frame and subframe sequence is obtained.

3. The 5G network interference testing method based on radio frequency coverage interference according to claim 1 is characterized in that: In step 5, the accurate time of transmitting the interference subframe is calculated according to the acquired information, and the covering interference signal is transmitted at the specific subframe time. The specific steps are as follows: Generate interference signal subframe: For the target subframe, tamper with specific key fields, and then perform the corresponding encoding process to generate interference subframe; Calculate the time T of transmitting the interference signal subframe tx =T rx +T offset -T adv , where T rx is the current time, T offset is the offset of the target subframe to the current time; An interference signal subframe synchronized with the legal transmitting device is transmitted at a specific subframe time with a power slightly higher than that of the legal transmitting device.

4. A 5G network interference test system based on radio frequency coverage interference, characterized in that: include: Legal transmitting equipment, used to configure transmission parameters and continuously transmit downlink broadcast signals and synchronization signals; The receiving device to be tested is used to configure receiving parameters and perform the initial random access process, and finally establish a connection with the legal transmitting device; Radio frequency interference equipment, used to receive the synchronization signal of the legal transmitting equipment to perform time and frequency synchronization, calculate the exact time of transmitting the interference subframe based on the synchronization information, and transmit the covering interference signal at a specific subframe time; Among them, the radio frequency interference device is synchronized with the legal transmitting device, and can transmit interference signal subframes at a power slightly higher than that of the legal transmitting device at a specific subframe time. The receiving device to be tested is used to collect communication quality indicators under normal communication environment and interference environment, and perform comparative analysis to obtain anti-interference performance.

5. The 5G network interference test system based on radio frequency coverage interference according to claim 4 is characterized in that: The radio frequency interference device also includes a module for calculating the cross-correlation between the received sequence and the standard synchronization sequence. The module implements fast calculation in the frequency domain through discrete Fourier transform, and then inversely transforms to the time domain to obtain the cross-correlation result.

6. The 5G network interference test system based on radio frequency coverage interference according to claim 4 is characterized in that: The radio frequency interference device also includes a module for generating an interference signal subframe, which generates the interference signal subframe by tampering with a specific key field of a target subframe and performing a corresponding encoding process.

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