A method and system for in-band interference signal estimation and identification

Abstract

The present invention relates to the field of wireless communication technology, and more particularly to a method and system for estimating and identifying in-band interference signals. The method comprises: S1: selecting different communication frequency tables and inputting channel estimation control parameters from an FCS communication radio interface, setting each communication frequency table containing N1 communication frequency points to {f0, f1, f2, ... f n‑1}, where the number of communication channels is N and the channel bandwidth is Δf; S2: Evaluate the channel quality parameters of each communication channel in the communication frequency table to obtain a channel quality level table with N communication channel quality levels; S3: Use the channel quality level table to complete a round of judgment of the communication channel quality of the communication frequency table in passive mode, thereby making a frequency selection decision. The present invention implements channel quality evaluation through a combination of active and passive modes, significantly reducing the time and computational complexity of interference signal identification and processing, and enabling rapid selection of the optimal communication channel.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wireless communication technology, more particularly, to an in-band interference signal estimation and identification method and system. BACKGROUND

[0002] With the development of wireless communication technology, wireless communication products are increasingly rich, and the interference problem of wireless signal is increasingly serious, especially in military radio communication, not only to face the harsh electromagnetic environment in the battlefield, but also to cope with the enemy's targeted counter-communication means. Therefore, in the design of the radio, the anti-information interception, anti-jamming performance and communication stability of the radio become the key indicators of the radio design. In the design of the ultra-short wave radio, the commonly used anti-jamming technologies include: spread spectrum communication technology, error correction coding and interleaving technology, free channel search technology, power adaptive technology and pilot sequence randomization technology. Among them, the free channel search (FCS) technology is a new type of anti-jamming communication technology, and the implementation method of this technology is mainly to scan and judge the communication channel on the working frequency band of the radio receiver, and select the optimal communication channel for radio transceiver. Therefore, how to search for the optimal communication channel becomes the key to realize this communication technology.

[0003] However, there is usually channel interference when selecting the optimal communication channel, and the channel interference mainly includes blocking interference, aiming interference and sweep interference. Therefore, in order to select the optimal communication channel to realize the FCS communication technology, the key is to accurately estimate the channel interference. The main modes of channel interference estimation include: active mode and passive mode. The active mode mainly estimates the bit error rate, multipath delay and frequency offset and other parameters by using the transceiver channel search mode frame during the communication of the two radios, exchanges the optimal channel information of the environment where the transceiver is located, and makes a reference for the radio to select the communication channel. The passive mode mainly switches the frequency point at regular intervals when the radio receiver is idle, cyclically scans the signal reception information of each channel, judges the interference of each channel, and forms or updates the channel quality ranking table. In FCS communication, it is difficult to select the channel with the best quality by using a separate active mode or a separate passive mode. The implementation of the active mode mainly relies on the related communication protocol, but the support of the passive mode is needed on this basis to enable the radio to quickly and comprehensively select the optimal communication channel.

[0004] Therefore, in view of the above communication characteristics, the present application combines the design characteristics of the ultra-short wave radio, and according to the channel interference, the interference signals are divided into wideband interference and single frequency interference. A kind of in-band interference signal estimation and identification method and system are designed, which is applied to the system device to realize the judgment of the communication channel quality in the passive mode of FCS communication, and is applied in engineering practice. SUMMARY

[0005] The present application aims to overcome at least one of the above-mentioned defects of the prior art, and provides an in-band interference signal estimation and identification method and system for evaluating channel quality by combining active mode and passive mode, greatly reducing the time and computation of interference signal identification and processing, and being able to quickly select the optimal communication channel.

[0006] In a first aspect, the technical solution adopted by the present application is an in-band interference signal estimation and identification method, which comprises:

[0007] S1: selecting different communication frequency tables and inputting channel estimation control parameters from the FCS communication station interface, setting N1 communication frequency points contained in each communication frequency table as {f0, f1, f2,..., fN-1}, wherein the number of communication channels is N, and the channel bandwidth is Δf; n-1}, wherein the number of communication channels is N, and the channel bandwidth is Δf;

[0008] S2: evaluating the channel quality parameters of each communication channel in the communication frequency table to obtain a channel quality level table with N communication channel quality levels;

[0009] S3: completing a round of communication channel quality judgment of the communication frequency table in passive mode according to the channel quality level table, thereby making a frequency selection decision.

[0010] In the present application, a passive mode channel parameter evaluation method is mainly described, wherein the common broadband interference signals such as sweep interference, blocking interference and suppression interference in the communication environment are uniformly converted into energy levels to represent their interference strengths, thereby greatly reducing the data processing amount of the upper processor module, and the channel quality level table is obtained by evaluating the quality parameters of each channel, which can ensure that a channel with high quality is selected for communication, reduces communication failure and data loss caused by channel interference or fading, thereby improving the reliability of the overall communication, and the communication channel quality judgment of the communication frequency table in passive mode is directly completed according to the generated channel quality level table, thereby the system can directly make a frequency selection decision according to the judgment result, effectively avoiding communication on a channel with large interference, reducing the interference between adjacent channels, improving the overall quality of the signal, thereby improving the clarity and stability of the transmission, and since the communication channel quality judgment in the FCS communication passive mode is to periodically evaluate the channel quality during the idle period of the receiver, the channel can be switched to a better one in time when the channel quality changes, so as to maintain good communication quality.

[0011] Preferably, the step S2 comprises:

[0012] S21: mixing the input radio frequency signal to generate a zero intermediate frequency baseband signal, then AD sampling and down-conversion filtering the baseband signal, outputting a digital signal with a sampling rate of f s , and storing the N2 sampling point data into a memory;

[0013] S22: the memory outputs FFT enable after completing the N2 sampling point data storage, sequentially outputs reading address and reads N2 sampling points for FFT transform processing to generate frequency domain data, and outputs FFT values corresponding to N2 frequency points to obtain FFT processing results;

[0014] S23: calculating signal strength corresponding to the N2 frequency points according to the FFT processing results;

[0015] S24: performing wideband interference processing and single frequency interference processing on the signal strength calculation results respectively to obtain channel parameter calculation results;

[0016] S25: sorting and comparing the channel parameter calculation results obtained by S24 with input channel estimation control parameters, and then generating a channel quality level table by comprehensively processing all data.

[0017] In the present application, the input signal is mixed, sampled and FFT transformed, then the energy of the processed wideband interference signal is calculated, the square value of the modulus value is directly used as the energy reference value, and finally the interference level is output by direct evaluation, so that the logarithmic operation is not needed, the data amount in the calculation process is effectively reduced, the time for interference signal identification and processing is reduced, and the processing efficiency is improved.

[0018] Preferably, in the step S22, the frequency resolution of the FFT results of the N2 frequency point data is f s / N2, and the FFT values corresponding to the N2 frequency points {0, 1, 2,..., (N2-1)} are

[0019] {(a0+b0j), (a1+b1j),..., (aN2-1+bN2-1j)}. (N2-1) (N2-1)

[0020] Wherein a is the sampling frequency point i data, as a complex real part; b is the sampling frequency point q data, as a complex imaginary part; and j is an imaginary unit.

[0021] In the present application, the output FFT value can help identify noise and interference in the signal. In the frequency domain, noise and interference usually appear as an increase in energy at specific frequency points. By analyzing the FFT value, these interferences can be found and reduced, and the signal quality can be improved.

[0022] ​​Preferably, in order to reduce the amount of calculation in the step S23, the intensity calculation formula of the ith frequency point is set as the square of the modulus of the FFT value of each frequency point, and the intensity calculation formula is:

[0023]

[0024] The signal intensity corresponding to the final output signal frequency point is:

[0025] {(0, E0), (1, E1),..., (N2-1, EN2-1)}. (N2-1)

[0026] By using the square of the modulus of the FFT value as the energy reference value, the calculation process is simplified, the amount of data calculation is reduced, and the signal processing efficiency is improved.

[0027] Preferably, in the step S24, the wideband interference processing includes:

[0028] S241: calculating the average energy value of the data within the Δf bandwidth;

[0029] S242: setting h threshold value ranges in advance and dividing the wideband interference level into h levels according to the calculated average energy value;

[0030] S243: outputting the channel wideband interference evaluation value P1 according to the threshold formula.

[0031] Preferably, the average energy value calculation formula is:

[0032]

[0033] Wherein, U is the average energy value, N2 is the number of frequency points, E i is the signal intensity.

[0034] By pre-setting several threshold value ranges to divide the wideband interference level into several levels, the strength and nature of the interference can be more systematically evaluated, the reliability of the communication is improved, and then the threshold formula is used to output the channel wideband interference evaluation value, so that the staff can dynamically adjust the resource allocation of the channel according to the interference evaluation value, and select the optimal communication channel, thereby effectively managing and reducing the impact of interference on communication.

[0035] Preferably, in the step S24, the single frequency interference processing includes: sorting the signal intensity within the N2 frequency points, finding out P2 FFT frequency points greater than ten times the average energy, and if P2>0, there are P2 single frequency interference frequency points within the Δf bandwidth of the communication channel.

[0036] ​By finding the frequency point greater than ten times the average energy, the possible interference source can be effectively identified, and in the wireless communication system, single frequency interference can seriously affect the signal quality, by identifying and processing these interference frequency points, the signal-to-noise ratio of the signal can be significantly improved, thereby improving the quality and stability of the communication. At the same time, the existence of single frequency interference may lead to waste of spectrum resources, by identifying and managing the interference frequency points, the use of spectrum can also be optimized, avoiding communication on the interference frequency points, and ensuring effective spectrum allocation.

[0037] In another aspect, the present application also provides an in-band interference signal estimation and identification system, the system comprises:

[0038] The receiver channel control module is used for mixing the input radio frequency signal to generate a zero intermediate frequency baseband signal, and providing the calculated channel estimation control parameters for several modules of the system.

[0039] The AD module is used for AD sampling and down-conversion filtering of the baseband signal, and outputs a digital signal with N2 sampling points and a sampling rate of f s .

[0040] The data storage module is used for storing N2 sampling point data and outputting FFT enable.

[0041] The FFT transform module is used for sequentially outputting data read addresses, inputting read data for FFT processing to generate frequency domain data, and obtaining the FFT processing result of N2 frequency point data.

[0042] The signal energy calculation module is used for calculating the signal strength corresponding to the N2 frequency point data according to the FFT processing result.

[0043] The interference identification module includes a wideband interference identification unit and a single frequency interference identification unit, wherein the wideband interference identification unit is used for interference degree judgment, and the single frequency interference identification unit is used for interference frequency point data calculation.

[0044] The channel quality parameter table generation module is used for sorting and comparing the channel single calculation result of the interference identification module with the calculated channel estimation control parameters, and generating a channel quality level table containing N communication channel quality levels when the last channel interference parameter calculation is completed.

[0045] The frequency selection decision module is used for completing the judgment of the communication channel quality of the passive mode communication frequency table according to the channel quality level table, and making a frequency selection decision.

[0046] In the system, the above-mentioned modules cooperate with each other to realize the following: the energy level is used to represent the interference degree of the wideband interference signal, and the interference is processed in the manner of being normalized as the wideband interference; the aiming interference and the smart interference are identified in the manner of a single frequency point energy value; and different interference modes are unified into two interference modes according to the interference characteristics, so as to greatly reduce the time and the operation amount of the interference signal identification and processing. Meanwhile, the evaluated channels are sorted according to a certain sorting algorithm, and a channel quality level table is finally outputted, which greatly reduces the data processing amount of the upper processor module. The communication channel quality in the passive mode can be judged according to the generated channel quality level table, so that the frequency selection decision is made, the communication in the channel with large interference is effectively avoided, the interference between the adjacent channels is reduced, and the overall signal quality is improved.

[0047] Preferably, the intensity calculation formula of the i-th frequency point in the signal energy calculation module is the square of the modulus of the FFT value of each frequency point, and the formula is:

[0048]

[0049] Therefore, the signal intensity corresponding to each output signal frequency point is: {(0, E0), (1, E1),..., (N2-1, E (N2-1) ).

[0050] Preferably, in the wideband interference processing unit, the average energy value of the data in the Δf bandwidth is calculated first, and the formula is Then, h threshold value ranges are set in advance, the wideband interference level is divided into h levels according to the calculated U value, and finally the channel wideband interference evaluation value P1 is outputted according to the threshold formula.

[0051] The wideband interference level is divided into several levels by setting a plurality of threshold value ranges, so that the strength and the nature of the interference can be more systematically evaluated, the reliability of the communication is improved, and then the threshold formula is used to output the channel wideband interference evaluation value, so that the staff can dynamically adjust the resource allocation of the channel according to the interference evaluation value, and select the optimal communication channel, thereby effectively managing and reducing the influence of the interference on the communication.

[0052] Preferably, in the single frequency interference identification unit, the signal intensity in the N2 frequency points is sorted to obtain P2 FFT frequency points greater than ten times the average energy. If P2>0, the communication channel has P2 single frequency interference frequency points in the Δf bandwidth.

[0053] By finding the frequency point greater than ten times the average energy, the possible interference source can be effectively identified, and in the wireless communication system, single frequency interference can seriously affect the signal quality, by identifying and processing these interference frequency points, the signal-to-noise ratio of the signal can be significantly improved, thereby improving the quality and stability of the communication. At the same time, the existence of single frequency interference can lead to the waste of spectrum resources, by identifying and managing the interference frequency points, the use of spectrum can also be optimized, and communication on the interference frequency point is avoided to ensure effective spectrum allocation.

[0054] Compared with the prior art, the beneficial effects of the present application are:

[0055] (1) The broadband interference signals such as sweep interference, blocking interference and suppression interference commonly seen in communication environment are uniformly characterized by energy level to represent their interference strength, and are processed in the form of wideband interference; the interference signals such as aiming interference and smart interference are uniformly identified by single frequency point energy value; a plurality of different interference modes are unified into two interference modes according to the interference characteristics, which greatly reduces the time and operation amount of interference signal identification and processing.

[0056] (2) The channel quality is evaluated, and the evaluated channel is sorted according to a certain sorting algorithm, and finally a channel quality level table after sorting is output, which greatly reduces the data processing amount of the upper processor module.

[0057] (3) In the present application, the square value of the modulus value is directly taken as the energy reference value for the energy calculation of the broadband interference signal, and finally the interference level is directly evaluated and output, without logarithmic operation, and the data calculation amount in the calculation process is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0058] Figure 1 The method flow diagram provided by the present application.

[0059] Figure 2 The channel quality level representation provided by the present application.

[0060] Figure 3 The system structure diagram provided by the present application.

[0061] Figure 4 The FFT transform module diagram provided by the present application. DETAILED DESCRIPTION

[0062] The drawings of the present application are only used for illustrative description, and cannot be understood as a limitation of the present application. In order to better illustrate the following embodiments, some components in the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some known structures and their descriptions in the drawings may be omitted.

[0063] Example 1

[0064] like Figure 1 As shown, the technical solution adopted in this embodiment is a method for estimating and identifying an in-band interference signal, the method comprising:

[0065] Step S1: Select different communication frequency tables and input channel estimation control parameters from the FCS communication radio interface, and set the N1 communication frequency points contained in each communication frequency table to {f0, f1, f2, ... f n-1}, where the number of its communication channels is N and the channel bandwidth is Δf;

[0066] Step S2: Evaluate the channel quality parameters of each communication channel in the communication frequency table to obtain a channel quality level table having N communication channel quality levels;

[0067] Specifically, step S2 also includes the following steps:

[0068] Preferably, in step S21: the input RF signal is mixed to generate a zero intermediate frequency baseband signal, and then the baseband signal is AD sampled and down-converted and filtered, and the output sampling rate is f s The digital signal of each channel is assumed to have N2 sampling points required for quality analysis, and the data of N2 sampling points are stored in the memory;

[0069] Preferably, in step S22: after the memory completes the storage of N2 sampling point data, it outputs FFT enable, outputs the read addresses address0 to address(N2-1) in sequence, reads N2 sampling points for FFT transformation processing, and the data becomes frequency domain data after FFT processing. The frequency resolution of the FFT result of N2 frequency point data is f s / N2, which outputs the FFT value corresponding to N2 frequency points {0, 1, 2, ..., (N2-1)}

[0070] {(a0+b0j),(a1+b1j),......,(a (N2-1) +b (N2-1) j)},

[0071] Where a is the data of sampling frequency point i, which is the complex real part; b is the data of sampling frequency point q, which is the complex imaginary part; j is the imaginary unit.

[0072] Therefore, the FFT value output in the embodiment can help identify noise and interference in the signal. In the frequency domain, noise and interference usually appear as increased energy at specific frequency points. By analyzing the FFT value, these interferences can be found and reduced, thereby improving signal quality.

[0073] Preferably, in step S23, the signal strength corresponding to the N2 frequency points is calculated according to the FFT processing result; in order to reduce the calculation amount, the strength calculation formula of the ith frequency point is set as the square of the modulus of the frequency point FFT value, and the strength calculation formula is:

[0074]

[0075] The signal strength corresponding to the final output signal frequency point is:

[0076] {(0, E0), (1, E1),..., (N2-1, EN2-1)} (N2-1)

[0077] The signal strength calculation result is then output to the interference evaluation process in step S24.

[0078] Thus, by using the square of the modulus of the FFT value as the energy reference value, the calculation process is simplified, the data calculation amount is reduced, and the signal processing efficiency is improved.

[0079] Preferably, in step S24, the signal strength calculation result is subjected to wideband interference processing and single-frequency interference processing respectively to obtain the channel parameter calculation result.

[0080] In step S24, the wideband interference processing includes:

[0081] Step S241: average energy value calculation is performed on the data within the Δf bandwidth, and the average energy value calculation formula is:

[0082]

[0083] Wherein, U is the average energy value, N2 is the number of frequency points, E i is the signal strength.

[0084] Step S242: in this embodiment, 6 threshold value ranges are pre-set, and the wideband interference level is divided into 6 levels according to the calculated average energy value;

[0085] Step S243: output the channel wideband interference evaluation value P1 according to the threshold formula, and the threshold formula is:

[0086]

[0087] Specifically, the threshold value range can be set according to actual needs, and is not limited to the 6 threshold value ranges mentioned in this embodiment.

[0088] ​Thus, in the embodiment, the wideband interference level is divided into several levels by presetting several threshold value ranges, the strength and nature of the interference can be more systematically evaluated, the reliability of the communication is improved, and then the threshold formula is used to output the channel wideband interference evaluation value, so that the staff can dynamically adjust the resource allocation of the channel according to the interference evaluation value, and select the optimal communication channel, thereby effectively managing and reducing the impact of interference on communication.

[0089] Preferably, in step S24, the single-frequency interference processing includes: sorting the signal strength in the N2 frequency points, finding out the P2 number of FFT frequency points greater than ten times the average energy, and if P2>0, the communication channel has P2 single-frequency interference frequency points in the Δf bandwidth.

[0090] By finding out the frequency points greater than ten times the average energy, the possible interference source can be effectively identified, and in the wireless communication system, the single-frequency interference can seriously affect the signal quality, by identifying and processing these interference frequency points, the signal-to-noise ratio of the signal can be significantly improved, thereby improving the quality and stability of the communication. At the same time, the existence of single-frequency interference can lead to waste of spectrum resources, by identifying and managing the interference frequency points, the use of spectrum can also be optimized, communication on the interference frequency points is avoided, and effective spectrum allocation is ensured.

[0091] Preferably, in step S25, the channel parameter calculation result calculated in step S24 is sorted and compared with the input channel estimation control parameter, and there are 12 priority levels in total, and the specific sorting of the priority levels is shown in Table 1:

[0092]

[0093] Table 1

[0094] Then, when the last channel interference parameter is calculated, a channel quality level table is generated by comprehensively processing all the data, and the obtained channel quality level table is as shown in Figure 2 From Figure 2 it can be seen that the number of single-frequency interference frequency points, the wideband interference strength and the channel quality level are included in each channel, and the above three parameters can help the staff to quickly select the optimal communication channel.

[0095] Thus, in step S3, the communication channel quality of the communication frequency table in the passive mode can be quickly determined according to the generated channel quality level table, a frequency selection decision is made, the optimal communication channel is selected, and the time for identifying and processing the interference signal is effectively reduced, and the processing efficiency is improved.

[0096] The embodiment mainly describes a passive mode channel parameter evaluation method, which is suitable for the field of ultra-short wave communication, converts common broadband interference signals such as sweep interference, blocking interference and suppressing interference in a communication environment into energy levels to represent the interference strength, thereby greatly reducing the data processing amount of an upper processor module, and obtains a channel quality level table through evaluation of the quality parameters of each channel, which can ensure that a channel with high quality is selected for communication, reduces communication failure and data loss caused by channel interference or fading, improves the reliability of overall communication, and directly uses the generated channel quality level table to judge the communication channel quality in the passive mode, so that the system can make a frequency selection decision according to the judgment result, effectively avoids communication in a channel with large interference, reduces the interference between adjacent channels, improves the overall quality of signals, and improves the clarity and stability of transmission. In addition, since the judgment of the communication channel quality in the FCS passive mode is to periodically evaluate the channel quality in the idle period of the receiver, the channel can be switched to a better one in time when the channel quality changes, so that the communication quality is maintained.

[0097] Embodiment 2

[0098] As shown in Figure 3 , the embodiment provides an in-band interference signal estimation and identification system, which comprises:

[0099] A receiver channel control module is used to mix the input radio frequency signal to generate a zero intermediate frequency baseband signal, and the module further comprises a channel estimation control parameter input unit, which is connected with a data storage module, an FFT transform module, a signal energy calculation module, an interference identification module and a channel quality parameter table generation module respectively, and is used to control parameter input and provide the above-mentioned modules with calculated channel estimation control parameters.

[0100] An AD module comprises an ADC sampling unit and a down-conversion filtering unit, which are used to AD sample and down-conversion filter the baseband signal, and output a digital signal with N2 sampling points and a sampling rate of f s .

[0101] A data storage module is connected with the down-conversion filtering unit and the FFT transform module respectively, and is used to store the N2 sampling point data processed by the AD module and output FFT enable.

[0102] An FFT transform module is connected with the data storage module and the signal energy calculation module respectively, and its specific structure is as follows Figure 4As shown, the FFT transformation module outputs the data reading addresses address0 to address(N2-1) in sequence, and receives the input reading data and performs FFT processing in combination with the control parameters to generate frequency domain data, and obtains the FFT processing results of N2 frequency point data, and finally inputs them into the signal energy calculation module through the FFT result output interface for processing.

[0103] Among them, the frequency resolution of the FFT result of N2 frequency point data is f s / N2, which outputs the FFT value corresponding to N2 frequency points {0, 1, 2, ..., (N2-1)}

[0104] {(a0+b0j),(a1+b1j),......,(a (N2-1) +b (N2-1) j)};

[0105] Where a is the data of sampling frequency point i, which is the complex real part; b is the data of sampling frequency point q, which is the complex imaginary part; j is the imaginary unit.

[0106] The signal energy calculation module is connected to the FFT transformation module and the interference identification module respectively, and is used to calculate the signal strength corresponding to the N2 frequency point data based on the FFT processing results;

[0107] Preferably, the intensity calculation formula of the i-th frequency point in the signal energy calculation module is the square of the modulus of the FFT value of each frequency point, and the formula is:

[0108]

[0109] Therefore, the signal strength corresponding to each output signal frequency point is: {(0,E0),(1,E1),......(N2-1,E (N2-1) By using the square of the modulus of the FFT value as the energy reference value, the calculation process is simplified, the amount of data calculation is reduced, and the signal processing efficiency is improved.

[0110] An interference identification module, comprising a broadband interference identification unit and a single-frequency interference identification unit, wherein the broadband interference identification unit is used to determine the degree of interference, and the single-frequency interference identification unit is used to calculate interference frequency data;

[0111] Preferably, the broadband interference processing unit first calculates the average energy value of the data within the Δf bandwidth, and the formula is: Then, h threshold value ranges are pre-set and the broadband interference level is divided into h levels according to the calculated U value. Finally, the channel broadband interference evaluation value P1 is output according to the threshold formula.

[0112] In the embodiment, 6 threshold value ranges are preset, and the wideband interference level is divided into 6 levels according to the calculated average energy value; and finally, the channel wideband interference evaluation value P1 is output according to a threshold value formula, wherein the threshold value formula is:

[0113]

[0114] Therefore, in the system described in the embodiment, the wideband interference level is divided into several levels by presetting several threshold value ranges, so that the intensity and nature of the interference can be more systematically evaluated, and the reliability of communication is improved; then, the channel wideband interference evaluation value is output by using the threshold value formula, so that the staff can dynamically adjust the resource allocation of the channel according to the interference evaluation value, and select the optimal communication channel, thereby effectively managing and reducing the impact of interference on communication.

[0115] Preferably, in the single-frequency interference identification unit, the signal strength in the N2 frequency points is sorted to obtain P2 FFT frequency points greater than ten times the average energy, and if P2>0, the communication channel has P2 single-frequency interference frequency points in the Δf bandwidth.

[0116] By finding the frequency points greater than ten times the average energy, the possible interference source can be effectively identified, and in a wireless communication system, single-frequency interference can seriously affect the signal quality; by identifying and processing these interference frequency points, the signal-to-noise ratio of the signal can be significantly improved, thereby improving the quality and stability of the communication. Meanwhile, the existence of single-frequency interference can lead to waste of spectrum resources, and by identifying and managing the interference frequency points, the use of spectrum can also be optimized, communication on the interference frequency points can be avoided, and effective spectrum allocation can be ensured.

[0117] The channel quality parameter table generation module is connected to the single-frequency interference identification unit, the wideband interference processing unit, and the channel estimation control parameter input unit, respectively, and is used to sort and compare the channel single-frequency interference calculation results of the interference identification module with the already calculated channel estimation control parameters, and when the last channel interference parameter calculation is completed, all data are integrated to generate a channel quality level table containing N communication channel quality levels.

[0118] The frequency selection decision module is used to complete the judgment of the communication channel quality in the passive mode according to the channel quality level table, and make a frequency selection decision.

[0119] In the system, the above-mentioned modules cooperate with each other to realize the following: the interference degree of the wideband interference signal is represented by energy level, and is processed in the manner of being normalized as wideband interference; the interference signals such as the aiming interference and the smart interference are identified in the manner of single frequency point energy value; and a plurality of different interference modes are unified into two interference modes according to interference characteristics to be identified and calculated, which greatly reduces the time and operation amount of the interference signal identification and processing. Meanwhile, the evaluated channels are ranked according to a certain ranking algorithm, and a channel quality ranking table is finally output, which greatly reduces the data processing amount of the upper processor module, and the generated channel quality ranking table can be directly used to judge the communication channel quality in the passive mode, so that the frequency selection decision is made, the communication in the channel with large interference is effectively avoided, the interference between adjacent channels is reduced, and the overall signal quality is improved.

[0120] Obviously, the above-mentioned embodiments of the present application are only examples for clearly illustrating the technical solutions of the present application, and are not intended to limit the specific embodiments of the present application. Any modification, equivalent replacement and improvement within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for estimating and identifying an in-band interference signal, the method comprising: S1: Select different communication frequency tables and input channel estimation control parameters from the FCS communication radio interface, and set each communication frequency table to contain N1 communication frequency points. , where the number of communication channels is N and the channel bandwidth is ; S2: Evaluate the channel quality parameters of each communication channel in the communication frequency table to obtain a channel quality level table having N communication channel quality levels; S3: Complete a round of judgment on the communication channel quality of the communication frequency table in the passive mode according to the channel quality level table, and make a frequency selection decision; It is characterized in that the step S2 includes: S21: Mix the input RF signal to generate a zero-IF baseband signal, then perform AD sampling and down-conversion filtering on the baseband signal. The output sampling rate is The digital signal is assumed to have N2 sampling points, and the data of N2 sampling points are stored in the memory; S22: After the memory completes storing the data of N2 sampling points, it outputs FFT enable, outputs the read address in sequence, reads the N2 sampling points, performs FFT transformation processing to generate frequency domain data, and outputs the FFT values ​​corresponding to the N2 frequency points to obtain the FFT processing results; S23: Calculate the signal strength corresponding to N2 frequency points based on the FFT processing result; S24: performing broadband interference processing and single-frequency interference processing on the signal strength calculation result to obtain a channel parameter calculation result; S25: The channel parameter calculation results obtained by S24 are sorted and compared with the input channel estimation control parameters, and then all the data are integrated to generate a channel quality level table.

2. The method for estimating and identifying an in-band interference signal according to claim 1, wherein: In step S22, the frequency resolution of the FFT result of the N2 frequency point data is , which outputs N2 frequency points The corresponding FFT value is , where a is the data of sampling frequency i, as the complex real part; b is the data of sampling frequency q, as the complex imaginary part; j is the imaginary unit.

3. The method for estimating and identifying an in-band interference signal according to claim 2, wherein: In order to reduce the amount of calculation in step S23, the intensity calculation formula of the i-th frequency point is set to the square of the modulus of the FFT value of each frequency point. The intensity calculation formula is: ， The signal strength corresponding to the final output signal frequency is: 。 4. The method for estimating and identifying an in-band interference signal according to claim 3, wherein: In step S24, the broadband interference processing includes: S241: Yes The average energy value of the data within the bandwidth is calculated; S242: pre-setting h threshold value ranges and classifying the broadband interference level into h levels according to the calculated average energy value; S243: Output the channel broadband interference evaluation value P1 according to the threshold formula.

5. The method for estimating and identifying an in-band interference signal according to claim 4, wherein: The average energy value calculation formula is: in, is the average energy value, is the number of frequency points, is the signal strength.

6. The method for estimating and identifying an in-band interference signal according to claim 5, wherein: In step S24, the single-frequency interference processing includes: sorting the signal strengths within N2 frequency points, finding P2 FFT frequency points with energy greater than ten times the average energy, and if P2>0, then the communication channel has P2 single-frequency interference frequency points within the Δf bandwidth.

7. An in-band interference signal estimation and identification system, characterized in that: The system comprises: Receiver channel control module: used to mix the input RF signal to generate a zero-IF baseband signal and provide calculated channel estimation control parameters to several modules of the system; AD module: used to perform AD sampling and down-conversion filtering on the baseband signal, and output a digital signal with N2 sampling points and a sampling rate of fs; Data storage module: used to store N2 sampling point data and output FFT enable; The FFT transformation module is used to sequentially output the data reading address and input the read data for FFT processing to generate frequency domain data, and obtain the FFT processing results of N2 frequency point data; Signal energy calculation module: used to calculate the signal strength corresponding to N2 frequency point data based on the FFT processing results; Interference identification module: includes a broadband interference identification unit and a single-frequency interference identification unit, wherein the broadband interference identification unit is used to determine the interference degree, and the single-frequency interference identification unit is used to calculate the interference frequency data; A channel quality parameter table generation module is used to sort and compare the channel odd number calculation results of the interference identification module with the calculated channel estimation control parameters. After the last channel interference parameter is calculated, all data are integrated to generate a channel quality level table containing N communication channel quality levels. The frequency selection decision module is used to judge the quality of the communication channel in the passive mode according to the channel quality level table and make a frequency selection decision.

8. The in-band interference signal estimation and identification system according to claim 7, characterized in that: In the signal energy calculation module, the intensity calculation formula of the i-th frequency point is the square of the modulus of the FFT value of each frequency point, and the formula is: ， Therefore, the signal strength corresponding to each output signal frequency point is: .

9. The in-band interference signal estimation and identification system according to claim 8, characterized in that: In the broadband interference identification unit, first The average energy value of the data within the bandwidth is calculated using the formula: , then pre-set h threshold value ranges and divide the broadband interference level into h levels according to the calculated U value, and finally output the channel broadband interference evaluation value P1 according to the threshold formula.

10. The in-band interference signal estimation and identification system according to claim 9, characterized in that: In the single-frequency interference identification unit, the signal strength in N2 frequency points is sorted to obtain P2 FFT frequency points with a value greater than ten times the average energy. If P2>0, the communication channel is There are P2 single-frequency interference points within the bandwidth.

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