A method and system for adaptive control of ultra-short wave communication based on SDR

Abstract

This invention provides an adaptive control method and system for UHF communication based on SDR (Signal-to-Noise Ratio) estimation. It extracts channel quality parameters from the real-time received signal of the UHF communication link by estimating the signal-to-noise ratio (SNR) of each available channel and sensing interference temperature. Based on the mapping relationship between the channel quality parameters and modulation / coding strategies, the channel quality parameters are mapped to transmission waveform parameters of the UHF communication link. The modulation scheme and coding rate of the baseband processing unit are reconstructed in the SDR platform based on these transmission waveform parameters. The real-time bit error rate (BER) of the reconstructed UHF communication link is read, and the convergence deviation of the link quality is extracted from the BER. The stability of the switching decision threshold in the UHF communication link is corrected based on the convergence deviation and the channel quality parameters. Based on the above scheme, the stability adjustment of the switching decision threshold in UHF communication can be achieved.

Description

Technical Field

[0001] This invention relates to the field of ultra-shortwave communication technology, and more specifically, to an adaptive control method and system for ultra-shortwave communication based on SDR. Background Technology

[0002] Software-defined radio (SDR) is a technology architecture that migrates the modulation, demodulation, frequency conversion, and filtering functions implemented in hardware in traditional radio systems to the software layer. Through a programmable hardware platform and flexibly configurable software modules, it enables dynamic reconstruction of communication waveform parameters, operating frequency bands, channel coding, and other functions. This allows the same hardware device to support multiple different communication standards and protocols, providing high flexibility and scalability.

[0003] Existing technologies often employ preset fixed handover thresholds, which remain unchanged throughout the communication process. This makes them ill-suited to adapting to dynamic changes in channel conditions within complex electromagnetic environments. When channel quality deteriorates due to increased interference or signal fading, the fixed threshold cannot automatically decrease to trigger a handover to a more robust modulation and coding scheme. This results in the link maintaining high spectral efficiency even under low-quality channels, leading to a sharp increase in bit error rate and a decline in communication quality. Conversely, when channel quality improves, the fixed threshold cannot automatically increase to suppress premature handover, causing the system to continue using low-order modulation schemes even under favorable channel conditions, sacrificing spectral efficiency. Furthermore, the fixed threshold cannot distinguish between short-term channel fluctuations and long-term trend changes, easily triggering frequent ping-pong switching of modulation and coding schemes, increasing system overhead and affecting link stability. Therefore, achieving stable adjustment of the handover decision threshold in UHF communication to improve the transmission stability of UHF communication links in complex electromagnetic environments has become a challenge for the industry. Summary of the Invention

[0004] This invention provides an adaptive control method and system for UHF communication based on SDR, which can realize the stability adjustment of the switching decision threshold in UHF communication, thereby improving the transmission stability of UHF communication links in complex electromagnetic environments.

[0005] In a first aspect, the present invention provides an adaptive control method for ultra-shortwave communication based on SDR, comprising: Acquire real-time received signals from the UHF / UHF communication link; Multiple available channels in the UHF communication link are determined, and then channel quality parameters are extracted from the real-time received signal by estimating the signal-to-noise ratio of each available channel and sensing the interference temperature. Based on the mapping relationship between channel quality parameters and modulation and coding strategies, the channel quality parameters are mapped to the transmission waveform parameters of the UHF communication link. Based on the transmission waveform parameters, the modulation mode and coding rate of the baseband processing unit are reconstructed in the SDR platform. The real-time bit error rate of the UHF communication link after reconstruction is read, and the convergence deviation of the link quality is extracted from the real-time bit error rate. The switching decision threshold of modulation and coding in the UHF communication link is corrected for stability based on the convergence deviation and the channel quality parameters.

[0006] In some embodiments, determining multiple available channels in the UHF communication link specifically includes: Scan the preset UHF communication frequency bands to obtain the spectrum occupancy status of each channel; Based on the spectrum sensing results, channels occupied by strong interference signals are eliminated to generate an initial candidate channel set; By using all spectrum occupancy states, the occupancy rate of each channel in the initial candidate channel set is statistically analyzed over multiple consecutive periods to obtain multiple available channels.

[0007] In some embodiments, extracting channel quality parameters from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing of each available channel specifically includes: Pilot signals are extracted from each available channel, and the signal-to-noise ratio estimate is calculated based on the amplitude attenuation of the pilot symbols. Collect the background noise power spectrum of each available channel, and calculate the interference temperature sensing value based on the background noise power spectrum; The signal-to-noise ratio estimate and the interference temperature sensing value are weighted and fused to obtain the channel quality parameters.

[0008] In some embodiments, mapping the channel quality parameters to transmission waveform parameters of an ultra-shortwave communication link based on the mapping relationship between channel quality parameters and modulation and coding strategies specifically includes: A multi-level mapping table of preset channel quality parameter ranges and modulation and coding schemes, wherein each level of the multi-level mapping table corresponds to different modulation orders and coding rates; The channel quality parameters are compared with each level interval in the multi-level mapping table to obtain the matching modulation and coding scheme; The corresponding transmission waveform parameters are generated based on the matching modulation and coding scheme. The transmission waveform parameters include the modulation scheme, coding rate value and symbol rate, thus obtaining the transmission waveform parameters of the UHF communication link.

[0009] In some embodiments, extracting the convergence deviation of link quality from the real-time bit error rate specifically includes: Set a sliding time window and collect multiple real-time bit error rate samples of the reconstructed UHF communication link within each sliding time window; Calculate the moving average of the bit error rate samples within all sliding time windows, and use this moving average as the current steady-state indicator of link quality; The current steady-state index is compared with the preset target bit error rate threshold to obtain the convergence deviation of the link quality.

[0010] In some embodiments, the stability correction of the modulation and coding switching decision threshold in the UHF communication link based on the convergence deviation and the channel quality parameters specifically includes: When the convergence deviation exceeds the preset deviation tolerance range, the current modulation and coding switching decision threshold and channel environment mismatch are determined. The threshold correction direction and correction step size are determined based on the sign and magnitude of the convergence deviation. If the convergence deviation is positive, the switching decision threshold is lowered; if the convergence deviation is negative, the switching decision threshold is raised. The revised switching decision threshold is updated in the adaptive control module of the SDR platform for use in the next modulation and coding scheme switching decision.

[0011] In some embodiments, the radio frequency front-end module in the SDR platform is used to acquire the real-time received signal of the UHF communication link.

[0012] Secondly, the present invention provides an SDR-based adaptive control system for ultra-shortwave communication, including a switching correction unit, wherein the switching correction unit includes: The acquisition module is used to acquire real-time received signals from the UHF communication link; The processing module is used to determine multiple available channels in the ultra-shortwave communication link, and then extract channel quality parameters from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing of each available channel. The processing module is also used to map the channel quality parameters to the transmission waveform parameters of the UHF communication link according to the mapping relationship between the channel quality parameters and the modulation and coding strategy, reconstruct the modulation mode and coding rate of the baseband processing unit in the SDR platform based on the transmission waveform parameters, read the real-time bit error rate of the UHF communication link after reconstruction, and extract the convergence deviation of the link quality from the real-time bit error rate. The execution module is used to perform stability correction on the switching decision threshold of modulation and coding in the UHF communication link based on the convergence deviation and the channel quality parameters.

[0013] Thirdly, the present invention provides a computer device, the computer device including a memory and a processor, the memory for storing a computer program, and the processor for calling and running the computer program from the memory, so that the computer device executes the above-described SDR-based adaptive control method for ultra-shortwave communication.

[0014] Fourthly, the present invention provides a computer-readable storage medium storing instructions or code that, when executed on a computer, cause the computer to implement the aforementioned SDR-based adaptive control method for ultra-shortwave communication.

[0015] The technical solutions provided by the embodiments disclosed in this invention have the following beneficial effects: This invention provides an adaptive control method and system for ultra-shortwave communication based on SDR. The method involves: acquiring real-time received signals from an ultra-shortwave communication link; determining multiple available channels in the link; extracting channel quality parameters from the real-time received signals through signal-to-noise ratio estimation and interference temperature sensing for each available channel; mapping the channel quality parameters to transmission waveform parameters of the ultra-shortwave communication link according to the mapping relationship between the channel quality parameters and modulation / coding strategies; reconstructing the modulation scheme and coding rate of the baseband processing unit in the SDR platform based on the transmission waveform parameters; reading the real-time bit error rate of the reconstructed ultra-shortwave communication link; extracting the convergence deviation of the link quality from the real-time bit error rate; and performing stability correction on the switching decision threshold of modulation / coding in the ultra-shortwave communication link based on the convergence deviation and the channel quality parameters.

[0016] Therefore, in this invention, the switching decision threshold of modulation and coding in the UHF communication link is stably corrected based on the convergence deviation and the channel quality parameters. First, determining the channel quality parameters yields a quantitative index that comprehensively characterizes the transmission capability of the available channel. This channel quality parameter integrates measurement results from two dimensions: pilot signal-to-noise ratio estimation and interference temperature sensing. The signal-to-noise ratio estimation reflects the strength level of the useful signal, while the interference temperature sensing reflects the degree of external interference contamination of the channel. The comprehensive index formed by the weighted fusion of these two parameters can fully describe the actual availability of the channel. The channel quality parameter that integrates interference sensing effectively distinguishes the different impact mechanisms of channel fading and external interference on communication quality, avoiding misjudging interference as signal attenuation or attenuation as interference. Then, determining the convergence deviation yields the dynamic deviation between the actual performance of the link and the target performance. This convergence deviation is used to obtain a steady-state index of the real-time bit error rate of the reconstructed link through a sliding time window. The threshold is extracted and compared with a preset target bit error rate threshold. Essentially, it reflects the degree of matching between the current modulation and coding scheme switching decision threshold and the channel environment. When the convergence deviation is positive, it indicates that the bit error rate performance is inferior to the target requirement, and the current threshold setting is too high, causing the system to fail to switch to a more robust modulation and coding scheme in a timely manner. When the convergence deviation is negative, it indicates that the bit error rate performance is superior to the target requirement, and the current threshold setting is too low, causing the system to switch prematurely, sacrificing spectral efficiency. The amplitude of the convergence deviation further quantifies the degree of mismatch. By introducing the convergence deviation as a feedback quantity into the threshold correction mechanism, a closed-loop control loop from performance deviation to threshold adjustment is formed, enabling the switching decision threshold to adaptively calibrate according to changes in the channel environment, ensuring that the switching timing of the modulation and coding scheme always approaches the optimal balance point. In summary, based on the above scheme, the stability adjustment of the switching decision threshold in UHF communication can be achieved, thereby improving the transmission stability of UHF communication links in complex electromagnetic environments. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an exemplary flowchart of an SDR-based adaptive control method for ultra-shortwave communication according to some embodiments of the present invention; Figure 2 This is a control logic diagram of the SDR platform shown in some embodiments of the present invention; Figure 3 This is a schematic diagram of the process for determining convergence deviation according to some embodiments of the present invention; Figure 4 This is a schematic diagram of the structure of a switching correction unit according to some embodiments of the present invention; Figure 5 This is a schematic diagram of the structure of a computer device that implements an SDR-based adaptive control method for ultra-shortwave communication, according to some embodiments of the present invention. Detailed Implementation

[0019] To better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] refer to Figure 1 The figure is an exemplary flowchart of an SDR-based adaptive control method for ultra-shortwave communication according to some embodiments of the present invention. The SDR-based adaptive control method for ultra-shortwave communication mainly includes the following steps: In step 101, the real-time received signal of the UHF communication link is acquired.

[0021] It should be noted that in this invention, the radio frequency front-end module in the SDR platform is used to acquire the real-time received signal of the UHF communication link. The radio frequency front-end module is a hardware unit used to filter, amplify with low noise, perform frequency conversion and analog-to-digital conversion on the UHF communication signal received by the antenna. The UHF communication link is a communication channel used to establish a wireless connection between the transmitter and receiver in the UHF band. The real-time received signal is the digital baseband signal data that characterizes the modulated radio frequency waveform carried on the UHF communication link at the current moment.

[0022] In practice, the SDR platform receives electromagnetic wave signals in the UHF band via an antenna. The RF front-end module first performs bandpass filtering on the signal to remove out-of-band interference, and then uses a low-noise amplifier to boost the signal amplitude to the effective level range. The amplified signal is mixed with the local oscillator signal to downconvert the RF signal to an intermediate frequency (IF). After IF filtering and variable gain amplification, the signal is sent to an analog-to-digital converter (ADC) for discretization sampling at a preset sampling rate, converting the continuous analog signal into a discrete digital signal sequence. The digital signal sequence output by the ADC is sent to the baseband processing unit as the real-time received signal. This real-time received signal is the digital baseband data used for subsequent channel quality analysis and adaptive control decisions. The digital baseband signal output by the RF front-end module is used as the real-time received signal for the UHF communication link.

[0023] It should be noted that in this invention, Figure 2This is the control logic diagram of the SDR platform. The entire SDR platform starts with the user's host computer as the control origin. Operators send commands such as frequency, gain, bandwidth, and modulation mode through the terminal. The commands are transmitted to the main control unit for parsing and scheduling, and the system then enters a parallel control process. One channel controls the RF front-end to realize frequency synthesis, AGC automatic gain adjustment, RF filtering, and channel switching. The other channel controls the digital baseband unit, where the FPGA / DSP completes DDC downconversion, DUC upconversion, digital filtering, and demodulation encoding. The two signals converge to the ADC / DAC data channel, and the IQ baseband data is transmitted back to the host computer via a high-speed interface. Finally, the data is demodulated, displayed, and stored. At the same time, the system status is transmitted back to the control terminal in real time through the feedback link, forming a complete closed-loop control logic to realize the entire process of software radio transmission and reception and signal processing.

[0024] In step 102, multiple available channels in the UHF communication link are determined, and then channel quality parameters are extracted from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing of each available channel.

[0025] In some embodiments, determining multiple available channels in the UHF communication link can be achieved by the following steps: Scan the preset UHF communication frequency bands to obtain the spectrum occupancy status of each channel; Based on the spectrum sensing results, channels occupied by strong interference signals are eliminated to generate an initial candidate channel set; By using all spectrum occupancy states, the occupancy rate of each channel in the initial candidate channel set is statistically analyzed over multiple consecutive periods to obtain multiple available channels.

[0026] It should be noted that, in this invention, the spectrum occupancy status is a Boolean value that characterizes whether each channel in the UHF communication band is occupied by other signals at the current moment; the initial candidate channel set is a list of channel identifiers used to store the remaining available channels after eliminating strong interference channels; and the available channels are available communication resources used for dynamic channel selection and adaptive transmission in the UHF communication link.

[0027] In practice, firstly, the spectrum sensing module in the SDR platform divides the UHF communication frequency band into multiple equal-bandwidth channel units according to a preset channel allocation scheme. Taking the 30 MHz to 300 MHz UHF band as an example, with each channel having a default bandwidth of 25 kHz, this band can be divided into 10,800 channel units. The spectrum sensing module then sequentially tunes to the center frequency of each channel and measures the received signal strength indication value within that channel using an energy detection method. The measured value is compared with a preset idle threshold. If the signal strength is higher than the idle threshold, the channel is determined to be occupied; if it is lower than the idle threshold, the channel is determined to be idle, thus forming the spectrum occupancy status of each channel. Then, after acquiring the spectrum occupancy status of all channels, the spectrum sensing module iterates through each channel. For channels determined to be occupied, it further calculates the difference between the signal strength and the idle threshold. If this difference exceeds a preset strong interference judgment threshold, the channel is marked as a strong interference channel. The spectrum sensing module then removes channels from the available resources and arranges all remaining channels in order of channel number to form an initial candidate channel set. Finally, the spectrum sensing module repeats the spectrum scanning process over multiple consecutive sensing cycles, recording the spectrum occupancy status of each channel in the initial candidate channel set in each cycle. Taking ten consecutive sensing cycles as an example, for each channel in the initial candidate channel set, the total number of times it is determined to be occupied in these ten cycles is counted, and the occupancy rate of the channel is obtained by dividing the number of occupancy cycles by the total number of cycles. The occupancy rate is compared with a preset availability threshold. If the occupancy rate of a channel is lower than the availability threshold, it indicates that the channel has remained idle for a long period during the statistical cycle and is suitable for communication transmission. If the occupancy rate is higher than the availability threshold, it indicates that the channel is frequently occupied by other signals, and it is removed from the candidate set. All channels that meet the requirement of an occupancy rate lower than the availability threshold are considered as multiple available channels, and the selected set of available channels is used as the communication resource for dynamic channel selection in the UHF communication link.

[0028] In some embodiments, extracting channel quality parameters from the real-time received signal by means of signal-to-noise ratio estimation and interference temperature sensing of each available channel can be achieved by the following steps: Pilot signals are extracted from each available channel, and the signal-to-noise ratio estimate is calculated based on the amplitude attenuation of the pilot symbols. Collect the background noise power spectrum of each available channel, and calculate the interference temperature sensing value based on the background noise power spectrum; The signal-to-noise ratio estimate and the interference temperature sensing value are weighted and fused to obtain the channel quality parameters.

[0029] It should be noted that, in this invention, the signal-to-noise ratio estimate is a numerical value characterizing the ratio of useful signal power to noise power in the available channel; the interference temperature sensing value is a metric characterizing the degree of influence of external interference signals on the communication system in the available channel; and the channel quality parameter is a quantitative indicator used to evaluate the transmission capability of the available channel and guide the selection of modulation and coding schemes.

[0030] In practice, firstly, the baseband processing unit in the SDR platform separates the pilot symbol sequence from the real-time received signal. Pilot symbols are reference signals with known amplitude and phase inserted by the transmitter into the communication frame. The baseband processing unit compares the received pilot symbol amplitude with the locally stored original pilot symbol amplitude and calculates the amplitude attenuation between the two. For example, if the original pilot symbol amplitude is 2 and the received pilot symbol amplitude is 1, the attenuation is half. Based on the amplitude attenuation, the signal-to-noise ratio (SNR) estimate of the available channel is calculated. The calculation principle is that the ratio of signal power to noise power is inversely proportional to the square of the amplitude attenuation; a larger amplitude attenuation indicates more severe channel fading. The lower the signal-to-noise ratio (SNR) estimate, the better. The baseband processing unit traverses all available channels, calculating the SNR estimate for each channel sequentially, and using the SNR estimate as a fundamental parameter reflecting signal strength. Then, the spectrum sensing module in the SDR platform samples background noise for each available channel during the communication silence period, which is a specified time period during which the transmitter suspends signal transmission and only the receiver remains operational. Within the bandwidth of each available channel, the spectrum sensing module collects noise power values ​​at multiple frequency points with a preset frequency resolution, arranging these noise power values ​​in frequency order to form the background noise power spectrum of that channel. The calculation of the interference temperature sensing value is based on the background noise power spectrum and the standard noise floor. The degree of deviation from the standard noise limit is specifically determined by comparing the noise power value at each frequency point in the background noise power spectrum with the standard noise limit, and calculating the integral value of all noise power exceeding the standard noise limit. This integral value is the interference temperature sensing value. For example, if a broadband interference signal exists in a channel, the noise power values ​​at multiple frequency points in the background noise power spectrum will significantly exceed the standard noise limit, resulting in a large integral value and a high interference temperature sensing value, indicating that the channel is subjected to strong external interference. Finally, the baseband processing unit performs a weighted fusion calculation on the signal-to-noise ratio estimate and the interference temperature sensing value according to a preset weighting coefficient. The specific method of weighted fusion is as follows: the signal-to-noise ratio estimate is multiplied by the signal-to-noise ratio weighting coefficient to obtain the signal-to-noise ratio. The interference contribution component is obtained by multiplying the interference temperature sensing value by the interference temperature weighting coefficient. The interference temperature sensing value is transformed by taking the reciprocal or negative correlation during fusion, so that the fusion result is smaller when the interference is greater. The signal-to-noise ratio contribution component and the interference contribution component are added to obtain the channel quality parameter of the available channel. The value of the weighting coefficient is dynamically adjusted according to the communication scenario requirements. When the communication system pays more attention to signal strength, the signal-to-noise ratio weighting coefficient is increased. When the communication system pays more attention to anti-interference capability, the interference temperature weighting coefficient is increased. The baseband processing unit traverses all available channels and calculates the channel quality parameter of each channel in turn. The comprehensive value obtained after weighted fusion is used as the channel quality parameter characterizing the transmission capability of the available channel.

[0031] In step 103, the channel quality parameters are mapped to the transmission waveform parameters of the UHF communication link according to the mapping relationship between the channel quality parameters and the modulation and coding strategy. Based on the transmission waveform parameters, the modulation mode and coding rate of the baseband processing unit are reconstructed in the SDR platform. The real-time bit error rate of the UHF communication link after reconstruction is read, and the convergence deviation of the link quality is extracted from the real-time bit error rate.

[0032] In some embodiments, mapping the channel quality parameters to the transmission waveform parameters of an ultra-shortwave communication link based on the mapping relationship between channel quality parameters and modulation and coding strategies can be achieved by the following steps: A multi-level mapping table of preset channel quality parameter ranges and modulation and coding schemes, wherein each level of the multi-level mapping table corresponds to different modulation orders and coding rates; The channel quality parameters are compared with each level interval in the multi-level mapping table to obtain the matching modulation and coding scheme; The corresponding transmission waveform parameters are generated based on the matching modulation and coding scheme. The transmission waveform parameters include the modulation scheme, coding rate value and symbol rate, thus obtaining the transmission waveform parameters of the UHF communication link.

[0033] It should be noted that, in this invention, the multi-level mapping table is a preset data structure used to store the correspondence between channel quality parameter ranges and modulation and coding schemes; the matched modulation and coding scheme is a combination scheme used to determine the signal modulation order and channel coding rate under the current channel conditions; and the transmission waveform parameters are a specific set of parameters used to configure the SDR platform baseband processing unit to generate physical layer waveforms.

[0034] In practical implementation, firstly, the adaptive control module in the SDR platform pre-establishes a multi-level mapping table. This mapping table divides multiple continuous intervals according to the channel quality parameters in ascending order, with each interval corresponding to a set of modulation and coding schemes. For example, when the channel quality parameters are below the first threshold, it corresponds to binary phase shift keying modulation and one-third code rate channel coding, a combination with a low modulation order and strong anti-interference capability. When the channel quality parameters are between the first and second thresholds, it corresponds to quadrature phase shift keying modulation and half code rate channel coding. When the channel quality parameters are below the first threshold, it corresponds to quadrature phase shift keying modulation and half code rate channel coding. When the channel quality parameter is between the second and third thresholds, it corresponds to hexadecimal quadrature amplitude modulation (QAM) and a two-thirds code rate channel coding. When the channel quality parameter is higher than the third threshold, it corresponds to hexadecimal quadrature amplitude modulation (QAM) and a three-quarters code rate channel coding. The multi-level mapping table is stored in the configuration memory of the SDR platform for subsequent channel quality parameter comparison and modulation / coding method selection. Then, after the adaptive control module obtains the channel quality parameter of the currently available channel, it sequentially compares this value with the boundary values ​​of each interval in the multi-level mapping table, starting from the lowest interval and proceeding sequentially. The system determines whether the channel quality parameters fall within the current range. After comparison, it outputs the modulation scheme and coding rate corresponding to the range as the matching modulation and coding scheme. Finally, the adaptive control module extracts the corresponding transmission waveform parameters from the parameter configuration library based on the matching modulation and coding scheme. The modulation scheme parameter is used to determine the working mode of the constellation mapping module in the baseband processing unit, such as binary phase shift keying mode, quadrature phase shift keying mode, or hexadecimal quadrature amplitude modulation mode. The coding rate parameter is used to determine the encoder configuration of the channel coding module, including encoder type selection and puncturing mode setting, to achieve the corresponding effective coding rate. The symbol rate parameter is used to determine the sampling rate of the baseband pulse shaping filter and the digital-to-analog conversion rate of the RF front-end module. The symbol rate is selected to match the channel bandwidth, and is set by default to 80% to 90% of the channel bandwidth to ensure that the signal spectrum falls within the channel passband. The adaptive control module packages the three parameters into a transmission waveform parameter set and sends it to each functional module of the baseband processing unit, using the generated modulation scheme, coding rate value, and symbol rate as the transmission waveform parameters for configuring the SDR platform baseband processing unit.

[0035] In some embodiments, the modulation scheme and coding rate of the baseband processing unit are reconstructed in the SDR platform based on the transmission waveform parameters. The real-time bit error rate of the reconstructed VHF / UHF communication link can be read in the following manner: the adaptive control module in the SDR platform sends the transmission waveform parameters to the baseband processing unit. The baseband processing unit first reconfigures the constellation mapping module according to the modulation scheme parameters in the transmission waveform parameters. Taking quadrature amplitude modulation (QAM) as an example, if the modulation scheme parameter indicates a switch from quadrature phase shift keying (QPSK) to hexadecimal quadrature amplitude modulation (HAM), the constellation mapping module will adjust the symbol mapping table, mapping every four bits to one hexadecimal QAM symbol. Simultaneously, the baseband processing unit reconfigures the channel coding module according to the coding rate value parameters in the transmission waveform parameters. If the coding rate is... When the rate parameter indicates a switch from half-rate to two-thirds rate, the channel coding module adjusts the puncturing mode to change the effective output rate of the encoder. While maintaining the convolutional encoder structure, it selectively discards some parity bits according to the puncturing template at two-thirds rate. The baseband processing unit also reconfigures the sampling clock of the pulse shaping filter and the digital-to-analog converter module according to the symbol rate parameter in the transmission waveform parameters to ensure that the symbol rate of the baseband signal matches the channel bandwidth. After the reconstruction operation is completed, the baseband processing unit enters normal operation mode. The link monitoring module in the SDR platform continuously extracts the decoded data frames from the receiving link, calculates the ratio of the number of erroneous bits to the total number of received bits per unit time, and uses this ratio as the real-time bit error rate output of the reconstructed UHF communication link.

[0036] In some embodiments, the convergence deviation of link quality is extracted from the real-time bit error rate, with reference to... Figure 3 The figure is a schematic diagram of the process for determining convergence deviation in some embodiments of the present invention. In this embodiment, the determination of convergence deviation can be achieved by the following steps: In step 1031, a sliding time window is set, and multiple real-time bit error rate samples of the reconstructed UHF communication link are collected within each sliding time window; In step 1032, the moving average of the bit error rate samples within all sliding time windows is calculated, and this moving average is used as the current steady-state indicator of link quality. In step 1033, the current steady-state index is compared with the preset target bit error rate threshold to obtain the convergence deviation of the link quality.

[0037] It should be noted that, in this invention, the real-time bit error rate sample value is an instantaneous measurement value reflecting the accuracy of data transmission of the UHF communication link at a specified time; the current steady-state index of link quality is a smoothed estimate of the average bit error performance of the UHF communication link within a statistical time period; and the convergence deviation of link quality is an error value that measures the difference between the current link bit error performance and the target performance.

[0038] In practice, firstly, the link monitoring module in the SDR platform sets a sliding time window according to a preset time window length. A sliding time window is a data acquisition interval with a fixed width that slides forward over time. For example, if the preset sliding time window length is two seconds and the sliding step is one second, then the first window covers the period from zero to two seconds, the second window covers the period from one to three seconds, the third window covers the period from two to four seconds, and so on, forming a sequence of continuously overlapping sliding time windows. Within each sliding time window, the link monitoring module continuously collects the real-time error data of the reconstructed UHF communication link. The method for obtaining the bit rate sampling value and the real-time bit error rate sampling value is as follows: The link monitoring module calculates the ratio of the number of correctly decoded data bits at the receiving end to the total number of received data bits per unit time, and inverts the ratio to obtain the bit error rate; the link monitoring module collects multiple real-time bit error rate sampling values ​​within each sliding time window according to a preset sampling interval, forming the bit error rate sampling sequence for that window; then, the bit error rate values ​​at each sampling moment within the window are added together, and then divided by the total number of samples within the window to obtain the sliding average bit error rate for that window. The link monitoring module repeats the above calculation process for each sliding time window, and sets the sliding time corresponding to the current moment... The moving average of the bit error rate (BER) calculated using the inter-window method is used as the current steady-state indicator of link quality. This steady-state indicator effectively filters out instantaneous fluctuations and reflects the stable BER performance of the link in the recent time period. Finally, the link monitoring module reads the preset target BER threshold from the configuration memory. This threshold is the target BER performance standard that the communication system expects to achieve, and it is usually set according to the service type and service quality requirements. For example, for voice communication services, the target BER threshold is set to 0.1% by default; for data communication services, the target BER threshold is set to 0.1% by default. The link monitoring module then compares the current steady-state indicator with the target BER. Thresholds are compared, and the difference between the two is calculated as follows: the current steady-state index is subtracted from the target bit error rate threshold. If the current steady-state index is less than the target bit error rate threshold, the difference is negative, indicating that the link bit error rate performance is better than the target requirement. If the current steady-state index is greater than the target bit error rate threshold, the difference is positive, indicating that the link bit error rate performance is worse than the target requirement. If the two are equal, the difference is zero, indicating that the link bit error rate performance just meets the target requirement. The link monitoring module uses this difference as the convergence deviation of the link quality, and uses the difference between the current steady-state index and the target bit error rate threshold as the convergence deviation characterizing the gap between the link quality and the target.

[0039] In step 104, the switching decision threshold of modulation and coding in the UHF communication link is corrected for stability based on the convergence deviation and the channel quality parameters.

[0040] In some embodiments, the stability correction of the modulation and coding switching decision threshold in the UHF communication link based on the convergence deviation and the channel quality parameters can be achieved by the following steps: When the convergence deviation exceeds the preset deviation tolerance range, the current modulation and coding switching decision threshold and channel environment mismatch are determined. The threshold correction direction and correction step size are determined based on the sign and magnitude of the convergence deviation. If the convergence deviation is positive, the switching decision threshold is lowered; if the convergence deviation is negative, the switching decision threshold is raised. The revised switching decision threshold is updated in the adaptive control module of the SDR platform for use in the next modulation and coding scheme switching decision.

[0041] It should be noted that in this invention, when the convergence deviation exceeds the preset deviation tolerance range, a mismatch is determined between the current modulation and coding scheme switching decision threshold and the channel environment. Specifically, the adaptive control module in the SDR platform first reads the preset deviation tolerance range. This range is a symmetrical interval centered on zero deviation, used to determine whether the link performance is within acceptable fluctuation range. If the absolute value of the convergence deviation exceeds this tolerance range, it indicates that the current modulation and coding scheme switching decision threshold setting does not match the actual channel conditions, and threshold correction needs to be performed. The adaptive control module determines the threshold correction direction and correction step size based on the sign and amplitude of the convergence deviation. If the convergence deviation is positive, it indicates that the current steady-state index of the link is higher than the target bit error rate threshold, and the bit error rate performance is worse than the target requirements. In this case, the switching decision threshold needs to be lowered to make the... The system switches to a modulation and coding scheme with stronger anti-interference capability in advance under lower channel quality conditions. If the convergence deviation is negative, it indicates that the current steady-state index of the link is lower than the target bit error rate threshold and the bit error performance is better than the target requirement. At this time, it is necessary to increase the handover decision threshold so that the system can switch to a modulation and coding scheme with higher spectral efficiency under higher channel quality conditions. The correction step size is mapped according to the magnitude of the convergence deviation. The larger the magnitude, the larger the step size, and the smaller the magnitude, the smaller the step size. The adaptive control module adds the calculated correction amount to the current handover decision threshold to generate the corrected handover decision threshold, and updates and stores the threshold in the configuration register of the adaptive control module for the next modulation and coding scheme handover decision. The corrected handover decision threshold is used as the judgment benchmark for the subsequent modulation and coding scheme handover in adaptive control.

[0042] Furthermore, in another aspect of the present invention, in some embodiments, the present invention provides an SDR-based adaptive control system for ultra-shortwave communication, which includes a switching correction unit, referencing... Figure 4The figure is a schematic diagram of the structure of a switching correction unit according to some embodiments of the present invention. The switching correction unit includes: an acquisition module 201, a processing module 202, and an execution module 203, which are described below: Acquisition module 201, in this invention, is mainly used to acquire real-time received signals from the ultra-shortwave communication link; Processing module 202, in this invention, is used to determine multiple available channels in the ultra-shortwave communication link, and then extract channel quality parameters from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing of each available channel; It should be noted that the processing module 202 is also used to map the channel quality parameters to the transmission waveform parameters of the UHF communication link according to the mapping relationship between the channel quality parameters and the modulation and coding strategy, reconstruct the modulation mode and coding rate of the baseband processing unit in the SDR platform based on the transmission waveform parameters, read the real-time bit error rate of the UHF communication link after reconstruction, and extract the convergence deviation of the link quality from the real-time bit error rate. The execution module 203 in this invention is mainly used to perform stability correction on the switching decision threshold of modulation and coding in the UHF communication link based on the convergence deviation and the channel quality parameters.

[0043] The foregoing detailed examples of the SDR-based adaptive control method and system for ultra-shortwave communication provided by embodiments of the present invention. It is understood that the corresponding apparatus, in order to achieve the above functions, includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the examples described in the embodiments disclosed herein, the present invention can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0044] In some embodiments, the present invention also provides a computer device, the computer device including a memory and a processor, the memory for storing a computer program, and the processor for calling and running the computer program from the memory, so that the computer device executes the above-described SDR-based adaptive control method for ultra-shortwave communication.

[0045] In some embodiments, reference Figure 5The dashed lines in the figure indicate that the unit or module is optional. This figure is a schematic diagram of the structure of a computer device implementing an SDR-based adaptive control method for ultra-shortwave communication according to an embodiment of the present invention. The SDR-based adaptive control method for ultra-shortwave communication described in the above embodiments can be achieved through… Figure 5 The computer device shown is used to implement this, and the computer device includes at least one processor 301, a memory 302 and at least one communication unit 305. The computer device may be a terminal device, a server or a chip.

[0046] Processor 301 can be a general-purpose processor or a special-purpose processor. For example, processor 301 can be a central processing unit (CPU), which can be used to control computer devices, execute software programs, and process data from software programs. The computer device may also include a communication unit 305 for inputting (receiving) and outputting (transmitting) signals.

[0047] For example, the computer device may be a chip, and the communication unit 305 may be the input and / or output circuit of the chip, or the communication unit 305 may be the communication interface of the chip, which may be a component of a terminal device, network device or other device.

[0048] For example, the computer device may be a terminal device or a server, and the communication unit 305 may be a transceiver of the terminal device or the server, or the communication unit 305 may be a transceiver circuit of the terminal device or the server.

[0049] The computer device may include one or more memories 302 storing a program 304. The program 304 can be executed by a processor 301 to generate instructions 303, causing the processor 301 to execute the method described in the above method embodiments according to the instructions 303. Optionally, the memory 302 may also store data (such as a target audit model). Optionally, the processor 301 may also read data stored in the memory 302, which may be stored at the same storage address as the program 304, or it may be stored at a different storage address than the program 304.

[0050] The processor 301 and memory 302 can be configured separately or integrated together, for example, integrated on the system on chip (SOC) of the terminal device.

[0051] It should be understood that each step of the above method embodiment can be completed by hardware logic circuits or software instructions in the processor 301. The processor 301 can be a CPU, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, such as discrete gate, transistor logic devices, or discrete hardware components.

[0052] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0053] For example, in some embodiments, the present invention also provides a computer-readable storage medium storing instructions or code that, when executed on a computer, cause the computer to implement the above-described SDR-based adaptive control method for ultra-shortwave communication.

[0054] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0055] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An adaptive control method for ultra-shortwave communication based on SDR, characterized in that, The steps include the following: Acquire real-time received signals from the UHF / UHF communication link; Multiple available channels in the UHF communication link are determined, and then channel quality parameters are extracted from the real-time received signal by estimating the signal-to-noise ratio of each available channel and sensing the interference temperature. Based on the mapping relationship between channel quality parameters and modulation and coding strategies, the channel quality parameters are mapped to the transmission waveform parameters of the UHF communication link. Based on the transmission waveform parameters, the modulation mode and coding rate of the baseband processing unit are reconstructed in the SDR platform. The real-time bit error rate of the UHF communication link after reconstruction is read, and the convergence deviation of the link quality is extracted from the real-time bit error rate. The switching decision threshold of modulation and coding in the UHF communication link is corrected for stability based on the convergence deviation and the channel quality parameters.

2. The method as described in claim 1, characterized in that, Determining the multiple available channels in the aforementioned ultra-shortwave communication link specifically includes: Scan the preset UHF communication frequency bands to obtain the spectrum occupancy status of each channel; Based on the spectrum sensing results, channels occupied by strong interference signals are eliminated to generate an initial candidate channel set; By using all spectrum occupancy states, the occupancy rate of each channel in the initial candidate channel set is statistically analyzed over multiple consecutive periods to obtain multiple available channels.

3. The method as described in claim 1, characterized in that, Extracting channel quality parameters from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing for each available channel specifically includes: Pilot signals are extracted from each available channel, and the signal-to-noise ratio estimate is calculated based on the amplitude attenuation of the pilot symbols. Collect the background noise power spectrum of each available channel, and calculate the interference temperature sensing value based on the background noise power spectrum; The signal-to-noise ratio estimate and the interference temperature sensing value are weighted and fused to obtain the channel quality parameters.

4. The method as described in claim 1, characterized in that, The mapping of channel quality parameters to transmission waveform parameters of the UHF communication link based on the mapping relationship between channel quality parameters and modulation and coding strategies specifically includes: A multi-level mapping table of preset channel quality parameter ranges and modulation and coding schemes, wherein each level of the multi-level mapping table corresponds to different modulation orders and coding rates; The channel quality parameters are compared with each level interval in the multi-level mapping table to obtain the matching modulation and coding scheme; The corresponding transmission waveform parameters are generated based on the matching modulation and coding scheme. The transmission waveform parameters include the modulation scheme, coding rate value and symbol rate, thus obtaining the transmission waveform parameters of the UHF communication link.

5. The method as described in claim 1, characterized in that, The convergence deviation for extracting link quality from the real-time bit error rate specifically includes: Set a sliding time window and collect multiple real-time bit error rate samples of the reconstructed UHF communication link within each sliding time window; Calculate the moving average of the bit error rate samples within all sliding time windows, and use this moving average as the current steady-state indicator of link quality; The current steady-state index is compared with the preset target bit error rate threshold to obtain the convergence deviation of the link quality.

6. The method as described in claim 1, characterized in that, The stability correction of the modulation and coding switching decision threshold in the UHF communication link based on the convergence deviation and the channel quality parameters specifically includes: When the convergence deviation exceeds the preset deviation tolerance range, the current modulation and coding switching decision threshold and channel environment mismatch are determined. The threshold correction direction and correction step size are determined based on the sign and magnitude of the convergence deviation. If the convergence deviation is positive, the switching decision threshold is lowered; if the convergence deviation is negative, the switching decision threshold is raised. The revised switching decision threshold is updated in the adaptive control module of the SDR platform for use in the next modulation and coding scheme switching decision.

7. The method as described in claim 1, characterized in that, The RF front-end module in the SDR platform is used to acquire real-time received signals from the UHF communication link.

8. An SDR-based adaptive control system for ultra-shortwave communication, comprising a switching correction unit, characterized in that, The switching correction unit includes: The acquisition module is used to acquire real-time received signals from the UHF communication link; The processing module is used to determine multiple available channels in the ultra-shortwave communication link, and then extract channel quality parameters from the real-time received signal through signal-to-noise ratio estimation and interference temperature sensing of each available channel. The processing module is also used to map the channel quality parameters to the transmission waveform parameters of the UHF communication link according to the mapping relationship between the channel quality parameters and the modulation and coding strategy, reconstruct the modulation mode and coding rate of the baseband processing unit in the SDR platform based on the transmission waveform parameters, read the real-time bit error rate of the UHF communication link after reconstruction, and extract the convergence deviation of the link quality from the real-time bit error rate. The execution module is used to perform stability correction on the switching decision threshold of modulation and coding in the UHF communication link based on the convergence deviation and the channel quality parameters.

9. A computer device, characterized in that, The computer device includes a memory and a processor. The memory is used to store computer programs, and the processor is used to call and run the computer programs from the memory, causing the computer device to execute the SDR-based adaptive control method for ultra-shortwave communication as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions or code that, when executed on a computer, cause the computer to implement the SDR-based adaptive control method for ultra-shortwave communication as described in any one of claims 1 to 7.

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