Multi-band dynamic reconfigurable switching system based on software defined radio

Abstract

The invention relates to the technical field of wireless communication, in particular to a software defined radio-based multi-band dynamic reconfigurable switching system, which comprises an environment sensing module, a band analysis module, a reconfiguration decision module, a switching execution module and a verification module, wherein the environment sensing module is used for collecting an original time domain signal; the frequency band analysis module is used for generating an available frequency band feature list; the reconstruction decision module is used for calculating a comprehensive score of each frequency band and generating a corresponding reconstruction configuration instruction; the switching execution module is used for configuring an SDR radio frequency front end; and the verification module is used for detecting whether response is confirmed. According to the invention, a dynamic wireless communication system with high-precision spectrum identification and rapid reconstruction capabilities is constructed by realizing real-time sensing, intelligent decision and self-verification switching of a multi-band environment, so that the communication stability and the spectrum utilization efficiency are remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, in particular to a multi-band dynamic reconfigurable switching system based on software defined radio. BACKGROUND

[0002] With the rapid development of wireless communication technology, multi-band access and dynamic spectrum utilization have become the key direction to improve the spectrum efficiency of communication systems. Traditional wireless devices usually operate in a fixed frequency band. When the frequency band is interfered or the bandwidth is insufficient, the system often cannot switch to a better frequency band in time, resulting in communication interruption or rate reduction. The emergence of software defined radio (SDR) technology enables the flexible configuration of radio frequency front-end and baseband processing through software, thereby possessing the ability of cross-band communication and adaptive reconfiguration. However, in the actual multi-band communication environment, the dynamic change of spectrum occupation, the fluctuation of signal-to-noise ratio and the multi-path interference make the SDR system need to have more intelligent frequency band identification, decision and switching mechanism to realize stable communication.

[0003] In the prior art, there are still some technical problems in the switching strategy of the multi-band SDR system: first, there is a lack of real-time quantitative perception of the multi-band environment, which cannot accurately extract key features such as signal strength, interference noise power and channel occupancy; second, the balance between communication stability and rate demand is not fully considered in the frequency band selection process, resulting in a lack of dynamic adaptability in switching decision; third, there is a lack of rapid verification mechanism after frequency band switching, which cannot timely confirm whether the link establishment is successful, affecting the system reliability. Therefore, there is an urgent need for a multi-band dynamic reconfigurable switching system based on software defined radio to solve the above problems. SUMMARY

[0004] Based on the above purpose, the present application provides a multi-band dynamic reconfigurable switching system based on software defined radio.

[0005] A multi-band dynamic reconfigurable switching system based on software defined radio, comprising an environment perception module, a frequency band analysis module, a reconfiguration decision module, a switching execution module and a verification module; wherein: The environment perception module is used to scan multiple preset frequency bands through the SDR radio frequency front-end to collect original time domain signals; and to convert the signals into frequency domain to extract frequency band signal strength, interference noise power and channel occupancy; The frequency band analysis module calculates the instantaneous signal-to-noise ratio of each frequency band based on the signal strength and the interference noise power, estimates the available bandwidth based on the channel occupancy, and generates an available frequency band feature list containing the frequency band identifier, the instantaneous signal-to-noise ratio and the available bandwidth; Reconstruction decision module: configured to receive the available frequency band feature list, calculate the comprehensive score of each frequency band according to the preset stability weight and rate weight, and select the frequency band with the highest comprehensive score as the target switching frequency band, and generate the corresponding reconstruction configuration instruction; Switch execution module: configured to configure the local oscillator frequency and filter bandwidth of the SDR radio frequency front end according to the reconstruction configuration instruction, control the radio frequency switch to complete the switching of the target frequency band, and issue a physical layer synchronization signal to establish a communication link; Verification module: configured to send a predefined verification data packet through the target frequency band after completing the link synchronization, and detect whether an acknowledgement response from the communication opposite end is received within a preset time; if the acknowledgement response is detected, a switching success signal is output, otherwise a switching failure signal is output.

[0006] Optionally, the environment perception module comprises a frequency band scanning unit, a signal acquisition unit, a frequency domain conversion unit and a parameter extraction unit; wherein: The frequency band scanning unit is configured to control the SDR radio frequency front end to switch the local oscillator frequency to the center frequency of a plurality of preset frequency bands in a set time window, and configure the corresponding band-pass filter bandwidth, so that the SDR receiving channel completes signal access preparation for the specified frequency band; The signal acquisition unit is configured to synchronously sample the radio frequency signal received by each frequency band during the frequency band scanning process, and generate a raw time domain signal stream sequence corresponding to the frequency band; The frequency domain conversion unit is configured to perform fast Fourier transform on the time domain signal stream collected for each frequency band to obtain a frequency component distribution sequence, and calculate the power spectral density corresponding to each frequency component; The parameter extraction unit is configured to identify the main signal interval and the interference interval of the target frequency band in the spectrum result, and calculate the average power as the frequency band signal strength and interference noise power, and calculate the corresponding channel occupancy rate according to the in-band frequency occupancy ratio.

[0007] Optionally, the frequency domain conversion unit comprises: The window processing subunit is configured to perform windowing processing on the raw time domain signal sequence output by the signal acquisition unit before performing frequency domain transformation, to form a windowed signal sequence; The fast Fourier transform subunit is configured to perform fast Fourier transform on the windowed signal sequence to convert it from the time domain to the frequency domain, and generate a frequency component sequence in complex form; The power spectrum calculation subunit is configured to square the amplitude of the frequency component sequence in complex form to obtain the power spectral density distribution of each frequency component.

[0008] Optionally, the frequency band analysis module comprises a signal-to-noise ratio calculation unit, a bandwidth estimation unit and a feature list generation unit; wherein: A signal-to-noise ratio calculation unit is configured to receive the frequency band signal strength and the interference noise power output by the environment perception module, and calculate the instantaneous signal-to-noise ratio corresponding to each frequency band according to the energy ratio between the two, with the formula being: wherein SNR is the instantaneous signal-to-noise ratio; is the frequency band signal strength; is the interference noise power; A bandwidth estimation unit is configured to estimate the effective bandwidth resource available for communication from the total bandwidth according to the channel occupancy rate of each frequency band, with the formula being: wherein is the available bandwidth; is the total bandwidth of the frequency band; is the channel occupancy rate, representing the ratio of the number of occupied frequency points to the total number of frequency points; A feature list generation unit is configured to structure and arrange the frequency band identifier, the signal-to-noise ratio value and the available bandwidth value corresponding to each frequency band, and generate a uniform format available frequency band feature list.

[0009] Optionally, the reconstruction decision module comprises a score calculation unit, a target selection unit and a configuration generation unit; wherein: The score calculation unit is configured to receive the available frequency band feature list generated by the frequency band analysis module, obtain the instantaneous signal-to-noise ratio and the available bandwidth parameters corresponding to each frequency band therefrom, and call the preset stability weight and rate weight to perform weighted comprehensive scoring on each frequency band; The target selection unit is configured to compare the comprehensive scores of all frequency bands, and select the frequency band with the highest score value as the target switching frequency band in the current period; The configuration generation unit is configured to generate the corresponding reconstruction configuration instruction according to the center frequency, the available bandwidth and the channel parameters of the target switching frequency band, and call the system preset radio frequency parameter mapping table.

[0010] Optionally, the score calculation unit comprises: A feature normalization subunit is configured to perform dimensionless normalization processing on the instantaneous signal-to-noise ratio and the available bandwidth in the available frequency band feature list, so as to convert different dimensional indicators to a unified scoring scale; A weight reading subunit is configured to access the stability weight and rate weight configuration stored in the system parameter table, and dock the read weights to the comprehensive score calculation subunit; A comprehensive score calculation subunit is configured to calculate the comprehensive score of each frequency band, and form a key-value pair with the corresponding frequency band identifier.

[0011] Optionally, the configuration generation unit comprises: Parameter extraction subunit: used for extracting the center frequency, available bandwidth and channel modulation mode parameters from the target switching frequency band output by the target selection unit, and arranging them into structured parameter items; Parameter matching subunit: used for calling a preset radio frequency parameter mapping table, matching a corresponding local oscillator frequency setting value based on the center frequency, matching an optimal passband range of a band-pass filter based on the available bandwidth, and selecting a radio frequency switch control logic compatible with the channel modulation mode; Instruction generation subunit: used for encapsulating the matching result into a structured reconstruction configuration instruction, wherein the reconstruction configuration instruction includes a local oscillator target frequency of the target frequency band, a filter bandwidth and a radio frequency switch control signal.

[0012] Optionally, the switching execution module includes a frequency configuration unit, a filtering adjustment unit, a radio frequency channel switching unit and a link synchronization unit; wherein: The frequency configuration unit is used for receiving the local oscillator target frequency parameter in the reconstruction configuration instruction and issuing it to a frequency synthesis control interface of the SDR radio frequency front end; The filtering adjustment unit is used for extracting the filter bandwidth setting parameter in the reconstruction configuration instruction and controlling the upper and lower cutoff frequencies of the adjustable band-pass filter so as to match the bandwidth range corresponding to the target frequency band; The radio frequency channel switching unit is used for identifying the radio frequency switch control signal code in the reconstruction configuration instruction and calling the corresponding control logic to switch the currently activated radio frequency path in the SDR system to the radio frequency receiving and transmitting link corresponding to the target frequency band; The link synchronization unit is used for sending a synchronization start code and a predefined training sequence through a physical layer control logic after the frequency, filter and radio frequency channel are all configured, to drive the communication opposite end to complete clock recovery and frame synchronization.

[0013] Optionally, the verification module includes a data packet sending unit, a response detection unit and a result determination unit; wherein: The data packet sending unit is used for calling a predefined verification data packet from a system buffer after the link synchronization is completed, and sending it to the communication opposite end through the target frequency band to verify the availability of the current link; The response detection unit is used for starting a timer after the data packet is sent, and listening to the confirmation response signal returned by the communication opposite end within a preset time window; if the response is detected, the receiving time and the response content are recorded, and if the timeout is not detected, a timeout flag is generated; The result determination unit is used for determining whether the switching is successful according to the response detection result; if the confirmation response is received, a switching success signal is output, otherwise a switching failure signal is output, and the system control layer is reported for state updating.

[0014] Optionally, the verification data packet comprises a unique frame header identifier, a sequence number and a check field.

[0015] Advantages of the present application: The present application, by constructing a multi-module collaborative mechanism under the software-defined radio architecture, realizes a closed-loop process of spectrum environment perception, feature analysis, decision reconstruction, execution switching and result verification; the system can collect and analyze multi-band signal parameters in real time in a complex electromagnetic environment, form feature data based on quantization indexes such as signal-to-noise ratio, interference power and occupancy rate, and provide reliable basis for subsequent frequency band selection, thereby ensuring continuous and stable communication process in a dynamic spectrum.

[0016] The present application, by introducing a weight-configurable decision model and a parameter mapping mechanism, changes the frequency band switching process from qualitative judgment to quantitative optimization, and the system can flexibly adjust the stability and rate priority according to different business scenarios; combined with automatic radio frequency configuration execution and link verification process, the system can realize fast response and self-confirmation of frequency band switching. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only illustrate the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0018] Fig. 1 A multi-band dynamic reconfigurable switching system according to an embodiment of the present application; Fig. 2 A reconfiguration decision module according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] The present application will be described in detail below in conjunction with the drawings and specific embodiments. It should be noted that in order to make the embodiments more detailed, the following embodiments are the best, preferred embodiments, and other alternative ways can also be implemented by those skilled in the art for some known technologies; and the drawings are only used to more specifically describe the embodiments, and are not intended to specifically limit the present application.

[0020] It should be noted that in the specification, "one embodiment", "embodiment", "exemplary embodiment", "some embodiments" and the like indicate that the described embodiments can include specific features, structures or characteristics, but not necessarily every embodiment includes the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of those skilled in the art to realize this feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0021] In general, terminology can be understood at least in part from a context of a use of the terminology. For example, the term "one or more" as used herein, depending at least in part upon a context of a use of the term, can be used to describe any feature, structure, or characteristic in a singular sense or can be used to describe combinations of features, structures or characteristics in a plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors and, instead, can allow for existence of other factors not explicitly described.

[0022] As shown in Figs. 1-2 A multi-band dynamic reconfigurable switching system based on software defined radio includes an environment perception module, a frequency band analysis module, a reconfiguration decision module, a switching execution module, and a verification module; wherein: The environment perception module is used to scan multiple preset frequency bands through an SDR (software defined radio) radio frequency front end to collect original time domain signals; and to perform frequency domain conversion on the signals to extract frequency band signal strength, interference noise power, and channel occupancy rate; The frequency band analysis module is used to calculate the instantaneous signal-to-noise ratio of each frequency band based on the signal strength and the interference noise power, to estimate the available bandwidth based on the channel occupancy rate, and to generate an available frequency band feature list containing the frequency band identifier, the instantaneous signal-to-noise ratio, and the available bandwidth; The reconfiguration decision module is used to receive the available frequency band feature list, to calculate the comprehensive score of each frequency band according to the preset stability weight and the rate weight, to select the frequency band with the highest comprehensive score as the target switching frequency band, and to generate the corresponding reconfiguration configuration instruction; The switching execution module is used to configure the local oscillator frequency and the filter bandwidth of the SDR radio frequency front end according to the reconfiguration configuration instruction, to control the radio frequency switch to complete the switching of the target frequency band, and to issue a physical layer synchronization signal to establish a communication link; The verification module is used to send a predefined verification data packet through the target frequency band after completing the link synchronization, and to detect whether an acknowledgement response from a communication opposite end is received within a preset time; if the acknowledgement response is detected, a switching success signal is output, otherwise a switching failure signal is output.

[0023] The environment perception module includes a frequency band scanning unit, a signal acquisition unit, a frequency domain conversion unit, and a parameter extraction unit; wherein: The frequency band scanning unit is used to control the SDR radio frequency front end to switch the local oscillator frequency to the center frequency of multiple preset frequency bands in a set time window in sequence, and to configure the corresponding bandpass filter bandwidth, so that the SDR receiving channel completes signal access preparation for the specified frequency band; The signal acquisition unit is used to synchronously sample the radio frequency signals received for each frequency band during the frequency band scanning process, and to generate a sequence of original time domain signal streams corresponding to the frequency band; Frequency domain transformation unit: used to perform fast Fourier transform on the time domain signal stream acquired in each frequency band to obtain the frequency component distribution sequence and calculate the power spectral density corresponding to each frequency component; Parameter extraction unit: Used to identify the main signal interval and interference interval of the target frequency band in the spectrum results, and calculate their average power as the frequency band signal strength and interference noise power. At the same time, it calculates the corresponding channel occupancy rate based on the in-band frequency occupancy ratio. The specific calculation is as follows: ; ; ;in, Indicates the signal strength in the frequency band. Indicates the power of interference noise. Indicates channel occupancy rate; The first main signal interval Power values ​​at each frequency point For the interference interval Power values ​​at each frequency point , These represent the total number of frequency points in the main signal and interference intervals, respectively. The number of in-band frequency points where the power exceeds the noise threshold. This represents the total number of frequency points within the frequency band. Through the above design, it is possible to achieve quantitative perception of signal quality and spectrum occupancy status in multi-band wireless environments, providing complete and reliable basic data support for the frequency band analysis module.

[0024] The frequency domain conversion unit includes: Windowing subunit: This unit performs windowing processing on the original time-domain signal sequence output by the signal acquisition unit before performing frequency domain transformation. This reduces spectral leakage. The windowing process uses a Hamming window or Hanning window function. The windowed signal sequence is formed by multiplying each sampling point by the window function weight. Its calculation expression is as follows: ,in, This is the time-domain sampled signal after windowing. The original time-domain sampled signal, For the window function weights, For the first Each sampling time; Fast Fourier Transform (FFT) subunit: Used to perform a Fast Fourier Transform (FFT) on the windowed signal sequence, transforming it from the time domain to the frequency domain and generating a sequence of frequency components in complex form; the transformation result is represented as: ,in, For the first The complex amplitude of each frequency component, The number of points in the FFT. The imaginary unit, For the corresponding frequency components; Power spectrum calculation subunit: used for calculating the power spectrum density distribution of each frequency component by squaring the amplitude of the complex form of the frequency component sequence; the calculation expression is: wherein, is the power spectrum density of the th frequency component, represents the modulus of the complex amplitude; through the above frequency domain conversion process, the original time domain signal can be accurately mapped to the frequency domain, the analysis and quantization of the power distribution of the multi-band signal are realized, the high-resolution spectral energy basic data are provided for the parameter extraction unit, and the accuracy of the signal strength and interference noise power evaluation is improved.

[0025] The frequency band analysis module includes a signal-to-noise ratio calculation unit, a bandwidth estimation unit, and a feature list generation unit; wherein: The signal-to-noise ratio calculation unit: used for receiving the frequency band signal strength and interference noise power output by the environment perception module, calculating the instantaneous signal-to-noise ratio corresponding to each frequency band according to the energy ratio between the two, and reflecting the current communication quality; the calculation formula is: wherein, SNR is the instantaneous signal-to-noise ratio; is the frequency band signal strength; is the interference noise power; The bandwidth estimation unit: used for excluding the occupied part from the total bandwidth according to the channel occupancy rate of each frequency band, and estimating the effective bandwidth resource available for communication; the formula is: wherein, is the available bandwidth; is the total bandwidth of the frequency band; is the channel occupancy rate, indicating the ratio of the number of occupied frequency points to the total number of frequency points; The feature list generation unit: used for structurally arranging the frequency band identifier, signal-to-noise ratio value and available bandwidth value corresponding to each frequency band, generating an available frequency band feature list in a unified format, and calling the subsequent reconstruction decision module for comprehensive scoring and sorting selection; through the cooperative processing of the above units, the frequency band analysis module realizes the comprehensive quantization of the multi-band wireless resource in the communication quality and availability dimensions, improves the precision and flexibility of the frequency band screening, and provides basic data guarantee for the dynamic spectrum switching strategy.

[0026] The reconstruction decision module includes a score calculation unit, a target selection unit, and a configuration generation unit; wherein: The score calculation unit: used for receiving the available frequency band feature list generated by the frequency band analysis module, obtaining the instantaneous signal-to-noise ratio and available bandwidth parameters corresponding to each frequency band therefrom; and calling the preset stability weight and rate weight to perform weighted comprehensive scoring on each frequency band, for reflecting the comprehensive priority thereof in the current communication scenario; The target selection unit is configured to compare the comprehensive scores of all frequency bands, and select a frequency band with the highest score as a target switching frequency band in a current period, so as to ensure that the system achieves an optimal balance between channel quality and available resources. The configuration generation unit is configured to call a preset radio frequency parameter mapping table of the system according to a center frequency, an available bandwidth and a channel parameter of the target switching frequency band, and generate a corresponding reconstruction configuration instruction, which includes a local oscillator target frequency, a filter bandwidth and a radio frequency switch control signal, to guide the switching execution module to complete hardware configuration and channel reconstruction.

[0027] The score calculation unit includes: The feature normalization subunit is configured to perform dimensionless normalization processing on the instantaneous signal-to-noise ratio and the available bandwidth in the available frequency band feature list, so that indexes of different dimensions are converted to a unified score scale to form a stability index score and a rate index score for subsequent weighted calculation. The normalization calculation formula is: ; wherein, represents the stability index score; represents the rate index score; represents the instantaneous signal-to-noise ratio of the target frequency band; is a lower boundary of the signal-to-noise ratio; is an upper boundary of the signal-to-noise ratio; represents the available bandwidth of the target frequency band; is a lower boundary of the bandwidth; is an upper boundary of the bandwidth; when the calculation result exceeds the interval , boundary truncation processing is performed in the implementation; The weight reading subunit is configured to access the stability weight and the rate weight stored in the system parameter table, and dock the read weights to the comprehensive score calculation subunit to ensure the configurability and consistency under different service targets. The weight constraint is: , , wherein, represents the stability weight; represents the rate weight; The comprehensive score calculation subunit is based on and output by the feature normalization subunit, and and , for calculating a comprehensive score for each frequency band, and forming a key-value pair with the corresponding frequency band identification; the comprehensive score formula is: wherein, represents the frequency band comprehensive score; the above subunit, by normalizing the instantaneous signal-to-noise ratio and the available bandwidth to a unified scale, and combining the configurable stability weight and the rate weight for linear weighting, the score calculation process is consistent in mathematical form and engineering implementation, ensuring the priority of the frequency band under different service targets to be determined and reusable, providing clear and traceable quantitative basis for the sorting and decision of the target selection unit.

[0028] Table 1 Stability weight and rate weight table

[0029] The configuration generation unit includes: The parameter extraction subunit is configured to extract the center frequency, available bandwidth, and channel modulation mode parameters from the target switching frequency band output by the target selection unit, and arrange them into structured parameter items for subsequent matching; The parameter matching subunit is configured to call a preset radio frequency parameter mapping table, match the corresponding local oscillator frequency setting value based on the center frequency, match the optimal passband range of the band-pass filter based on the available bandwidth, and select the radio frequency switch control logic compatible with the channel modulation mode; Table 2 Radio frequency parameter mapping table

[0030] In the above table 2, the frequency band identification is a unique number allocated to each preset communication frequency band, which is used for fast indexing in the frequency band feature list and configuration instruction; the frequency range represents the center frequency interval available in the wireless system for the frequency band, which is used to match the center frequency of the target switching frequency band; the local oscillator target frequency is the setting frequency of the SDR radio frequency front-end local oscillator module, which directly determines the tuning center point of the received or transmitted signal; when the center frequency of the target frequency band falls within the range in the table, the parameter matching subunit automatically calls the corresponding local oscillator setting value; the filter bandwidth represents the physical filter passband width corresponding to the available bandwidth of the frequency band, which is used to ensure that the signal passes within the effective frequency range while suppressing adjacent frequency interference; the modulation mode represents the digital modulation scheme adopted by the frequency band, which is used to ensure matching with the channel parameters and guarantee subsequent link synchronization and communication stability; the radio frequency switch control signal represents the control instruction combination corresponding to the path switching of the radio frequency front-end, different frequency bands call different switch logic, which is used to connect specific radio frequency filter branches or amplification channels.

[0031] The instruction generation subunit is configured to encapsulate the matching result into a structured reconstruction configuration instruction, the reconstruction configuration instruction including a local oscillator target frequency of a target frequency band, a filter bandwidth, and a radio frequency switch control signal; through the cooperative operation of the above-mentioned subunits, the configuration generation unit can quickly match the optimal radio frequency configuration strategy based on the pre-defined parameter rules according to the communication requirements of the target frequency band, and generate a configuration instruction with a specified format and direct execution, thereby ensuring that the system has efficient and accurate bottom-layer hardware control capability when performing frequency band switching.

[0032] The switching execution module includes a frequency configuration unit, a filter adjustment unit, a radio frequency channel switching unit, and a link synchronization unit; wherein: The frequency configuration unit is configured to receive the local oscillator target frequency parameter in the reconstruction configuration instruction and send it to the frequency synthesis control interface of the SDR radio frequency front end, so as to realize phase-locked tuning of the local oscillator and ensure that the carrier frequency of the target frequency band is consistent with the system set value; The filter adjustment unit is configured to extract the filter bandwidth setting parameter in the reconstruction configuration instruction and control the upper and lower cutoff frequencies of the adjustable band-pass filter, so as to match the bandwidth range corresponding to the target frequency band and filter out the interference spectrum of the non-target frequency band, thereby improving the signal-to-noise ratio of subsequent communication; The radio frequency channel switching unit is configured to identify the radio frequency switch control signal code in the reconstruction configuration instruction and call the corresponding control logic to switch the currently activated radio frequency path in the SDR system to the radio frequency receiving and transmitting link corresponding to the target frequency band; The link synchronization unit is configured to send a synchronization start code and a pre-defined training sequence through the physical layer control logic after the frequency, filter, and radio frequency channel are all configured, so as to drive the communication opposite end to complete clock recovery and frame synchronization; through the series execution of the above-mentioned units, the switching execution module can accurately map the reconstruction configuration instruction generated by the upper layer into an operable radio frequency front-end control action, from frequency setting, filter tuning to path switching, synchronization link building, thereby forming a complete and closed-loop dynamic frequency band switching mechanism, and ensuring that the system has real-time switchable physical layer execution capability in a variable spectrum environment.

[0033] The verification module includes a data packet sending unit, a response detection unit, and a result determination unit; wherein: The data packet sending unit is configured to retrieve a pre-defined verification data packet from the system buffer after the link synchronization is completed, and send it to the communication opposite end through the target frequency band, so as to verify the availability of the current link; The response detection unit is configured to start a timer after the data packet is sent, and listen to the confirmation response signal returned by the communication opposite end within a pre-set time window; if the response is detected, the receiving time and the response content are recorded, and if the timeout is not detected, a timeout flag is generated; The result judging unit is used for judging whether the switching is successful according to the response detection result, outputting a switching success signal if a confirmation response is received, otherwise outputting a switching failure signal, and reporting to the system control layer for state updating; through the above structure, the verification module can realize the fast detection of the link validity after the frequency band switching, and ensure that the system has the real-time self-checking and confirmation capability in the multi-frequency band dynamic reconstruction.

[0034] The verification data packet comprises a unique frame header identifier, a serial number and a check field.

[0035] When the verification module completes the link synchronization, the operation process steps of the response detection are as follows after sending the verification data packet comprising the unique frame header identifier, the serial number and the check field through the target frequency band: S1: the response detection unit starts a receiving timer at the same time of sending the verification data packet, sets a fixed response waiting time window, and enters a listening state; S2: during the time window of the timer not being expired, continuously listens whether the receiving signal arrives at the target frequency band, and performs the field-by-field analysis on the received data, and focuses on extracting the following key elements for comparison: whether the frame header identifier is consistent with the locally sent data packet; whether the serial number in the response frame corresponds to the sent data packet; whether the check field passes the check logic check; S3: when the received response frame passes the check of the above three contents, the valid confirmation response is judged, the receiving window timer is immediately terminated, and the switching success signal is output; if no response frame is received within the response waiting time window, or the received frame does not conform to any check rule, the response failure is determined, and the switching failure signal is output; S4: no matter whether the response is successful or failed, the verification module outputs the final result to the system control logic layer through the result judging unit, which is used for the subsequent switching stability record or the triggering basis of the fault recovery mechanism.

[0036] The present application encompasses any substitution, modification, equivalent method and scheme made on the essence and scope of the present application. In order for the public to have a thorough understanding of the present application, the specific details are described in the following preferred embodiments of the present application, and the present application can also be completely understood without the description of these details for those skilled in the art. In addition, in order to avoid unnecessary confusion to the essence of the present application, the well-known methods, processes, procedures, elements and circuits are not described in detail.

[0037] The above is only the preferred embodiment of the present application, and it should be pointed out that, for those skilled in the art, without departing from the principle of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A multi-band dynamic reconfigurable switching system based on software-defined radio, characterized in that, It includes an environmental perception module, a frequency band analysis module, a reconstruction decision module, a handover execution module, and a verification module; among which: Environmental sensing module: used to scan multiple preset frequency bands through SDR radio frequency front end, collect raw time domain signals; and perform frequency domain transformation on the signals to extract frequency band signal strength, interference noise power and channel occupancy rate; Frequency band analysis module: Calculates the instantaneous signal-to-noise ratio of each frequency band based on signal strength and interference noise power, estimates the available bandwidth based on channel occupancy, and generates a list of available frequency band characteristics that includes frequency band identifier, instantaneous signal-to-noise ratio, and available bandwidth; Reconfiguration decision module: It is used to receive the list of available frequency bands, calculate the comprehensive score of each frequency band based on the preset stability weight and rate weight, select the frequency band with the highest comprehensive score as the target switching frequency band, and generate the corresponding reconfiguration configuration command. Switching execution module: Used to configure the local oscillator frequency and filter bandwidth of the SDR RF front end according to the reconfiguration configuration instructions, control the RF switch to complete the switching of the target frequency band, and send physical layer synchronization signals to establish a communication link; Verification module: After link synchronization is completed, it sends a predefined verification data packet through the target frequency band and detects whether an acknowledgment response is received from the communication peer within a preset time. If an acknowledgment response is detected, it outputs a handover success signal; otherwise, it outputs a handover failure signal.

2. The multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 1, characterized in that, The environmental perception module includes a frequency band scanning unit, a signal acquisition unit, a frequency domain conversion unit, and a parameter extraction unit; wherein: Frequency band scanning unit: Used to control the SDR RF front end to sequentially switch the local oscillator frequency to the center frequency of multiple preset frequency bands within a set time window, and configure the corresponding bandpass filter bandwidth so that the SDR receiving channel can complete the signal access preparation for the specified frequency band. Signal acquisition unit: used to synchronously sample the radio frequency signals received in each frequency band during the frequency band scanning process, and generate the original time domain signal stream sequence corresponding to the frequency band; Frequency domain transformation unit: used to perform fast Fourier transform on the time domain signal stream acquired in each frequency band to obtain the frequency component distribution sequence and calculate the power spectral density corresponding to each frequency component; Parameter extraction unit: used to identify the main signal interval and interference interval of the target frequency band in the spectrum results, and calculate its average power as the frequency band signal strength and interference noise power, and at the same time calculate the corresponding channel occupancy rate based on the in-band frequency occupancy ratio.

3. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 2, characterized in that, The frequency domain conversion unit includes: Window processing subunit: used to perform windowing processing on the original time-domain signal sequence output by the signal acquisition unit before performing frequency domain transformation, forming a windowed signal sequence; Fast Fourier Transform (FFT) subunit: Used to perform a Fast Fourier Transform on the windowed signal sequence, converting it from the time domain to the frequency domain and generating a sequence of frequency components in complex form; Power spectral density calculation subunit: used to calculate the square of the amplitude of the complex frequency component sequence in order to obtain the power spectral density distribution of each frequency component.

4. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 1, characterized in that, The frequency band analysis module includes a signal-to-noise ratio calculation unit, a bandwidth estimation unit, and a feature list generation unit; wherein: Signal-to-noise ratio (SNR) calculation unit: Receives the frequency band signal strength and interference noise power output from the environmental sensing module, and calculates the instantaneous SNR for each frequency band based on the energy ratio between the two. The formula is: Where SNR is the instantaneous signal-to-noise ratio; Signal strength in the frequency band; For interference noise power; Bandwidth estimation unit: used to estimate the effective bandwidth resources currently available for communication by removing the occupied portion from the total bandwidth based on the channel occupancy rate of each frequency band; the formula is: ,in, Available bandwidth; This refers to the total bandwidth of the frequency band. Channel occupancy rate, representing the ratio of occupied frequency points to the total number of frequency points; Feature list generation unit: Used to structure and organize the frequency band identifier, signal-to-noise ratio value and available bandwidth value corresponding to each frequency band, and generate a feature list of available frequency bands in a unified format.

5. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 1, characterized in that, The reconstruction decision module includes a scoring calculation unit, a target selection unit, and a configuration generation unit; wherein: Scoring Calculation Unit: Used to receive the list of available frequency band features generated by the frequency band analysis module, obtain the instantaneous signal-to-noise ratio and available bandwidth parameters corresponding to each frequency band, and call the preset stability weight and rate weight to perform a weighted comprehensive score for each frequency band; Target selection unit: Used to compare the comprehensive scores of all frequency bands and select the frequency band with the highest score as the target switching frequency band in the current cycle; Configuration generation unit: Used to generate corresponding reconfiguration configuration instructions by calling the system's preset radio frequency parameter mapping table based on the center frequency, available bandwidth and channel parameters of the target switching band.

6. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 5, characterized in that, The scoring calculation unit includes: Feature normalization subunit: used to perform dimensionless normalization processing on the instantaneous signal-to-noise ratio and available bandwidth in the available frequency band feature list, so that the indicators with different dimensions are converted to a unified scoring scale. Weight reading subunit: used to access the stability weight and rate weight configuration stored in the system parameter table, and connect the read weight to the comprehensive score calculation subunit; Comprehensive score calculation subunit: used to calculate the comprehensive score for each frequency band and form a key-value pair with the corresponding frequency band identifier.

7. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 5, characterized in that, The configuration generation unit includes: Parameter extraction subunit: used to extract the center frequency, available bandwidth and channel modulation mode parameters from the target switching frequency band output by the target selection unit, and organize them into structured parameter items; Parameter matching subunit: used to call the preset RF parameter mapping table, match the local oscillator frequency setting value based on the center frequency, match the optimal passband range of the bandpass filter based on the available bandwidth, and select compatible RF switch control logic according to the channel modulation method. Instruction generation subunit: used to encapsulate the matching result into a structured reconstruction configuration instruction, which includes the target local oscillator frequency, filter bandwidth, and RF switch control signal of the target frequency band.

8. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 1, characterized in that, The switching execution module includes a frequency configuration unit, a filter adjustment unit, an RF channel switching unit, and a link synchronization unit; wherein: Frequency configuration unit: used to receive the local oscillator target frequency parameters in the reconfiguration configuration command and send them to the frequency synthesis control interface of the SDR RF front end; Filtering adjustment unit: used to extract the filter bandwidth setting parameters in the reconstruction configuration command and control the upper and lower cutoff frequencies of the adjustable bandpass filter to match the bandwidth range corresponding to the target frequency band; RF channel switching unit: used to identify the RF switch control signal code in the reconfiguration instruction, and call the corresponding control logic to switch the currently active RF path in the SDR system to the RF receive and transmit link corresponding to the target frequency band; Link synchronization unit: After the frequency, filter and RF channel are configured, it sends the synchronization start code and predefined training sequence through physical layer control logic to drive the communication peer to complete clock recovery and frame synchronization.

9. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 1, characterized in that, The verification module includes a data packet sending unit, a response detection unit, and a result determination unit; wherein: Data packet sending unit: After link synchronization is completed, it retrieves a predefined verification data packet from the system cache and sends it to the communication peer through the target frequency band to verify the availability of the current link; Response detection unit: Used to start a timer after the data packet is sent and listen for the acknowledgment response signal returned by the communication peer within a preset time window; if a response is detected, the receiving time and response content are recorded; if no response is detected within the time limit, a timeout flag is generated. Result determination unit: Used to determine whether the handover is successful based on the response detection result. If a confirmation response is received, a handover success signal is output; otherwise, a handover failure signal is output and reported to the system control layer for status update.

10. A multi-band dynamic reconfigurable switching system based on software-defined radio according to claim 9, characterized in that, The verification data packet includes a unique frame header identifier, a sequence number, and a verification field.

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