Power internet of things communication system and signal processing method based on FBMC and micro-slot frequency hopping

Abstract

This invention discloses a power Internet of Things (IoT) communication system and signal processing method based on FBMC and micro-timeslot frequency hopping. It integrates the advantages of FBMC's high spectral efficiency and high robustness of frequency hopping with the flexible scheduling of micro-timeslots, eliminating the cyclic prefix, improving anti-pulse interference capability, and reducing the retransmission delay of power control information. The system's physical layer includes signal processing modules for both the transmitter and receiver. The transmitter consists of serial-to-parallel conversion, symbol mapping, a synthesis filter bank, and a frequency-hopping modulator; the receiver includes an analysis filter bank, a de-hopping unit, and a demapping unit. The system also includes a MAC layer FH / FBMC and micro-timeslot fusion module and a hybrid frequency-hopping retransmission module, achieving a combination of frequency and time domain capabilities and reliable low-latency transmission. Compared to OFDM, FBMC has superior energy concentration in the time and frequency domains, higher spectral efficiency, and stronger anti-multipath interference capability, making it suitable for ultra-reliable low-latency (uRLLc) power communication private networks.

Description

Technical Field

[0001] This invention relates to the field of power Internet of Things (IoT) data processing, specifically to a power IoT communication system and signal processing method based on FBMC and micro-timeslot frequency hopping. Background Technology

[0002] In the Power Internet of Things (PIoT) for transmission line monitoring, information collection and electrical control on towers and overhead cables place extremely stringent demands on communication assurance, particularly millisecond-level response speeds and extremely high transmission stability, which have become key factors restricting the improvement of power system efficiency. However, the presence of numerous power electronic devices and the start-up and shutdown of large equipment in the power grid generate strong impulse noise, multipath fading, and electromagnetic interference, leading to severe attenuation and distortion of wireless power private network communication signals. Furthermore, power wireless private networks on transmission lines typically require multi-hop transmission over long distances, and factors such as relay node storage / forwarding and data retransmission result in significant data transmission delays, seriously threatening the safe and stable operation of the power grid. Therefore, how to achieve ultra-reliable, low-latency (URLLC) power communication private networks within limited spectrum resources is a crucial direction for the current evolution of power IoT technology.

[0003] Currently, 5G wireless private network communication for the power IoT mainly employs Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. This technology divides a high-speed data stream into multiple parallel low-speed subcarrier streams, utilizing the orthogonality between subcarriers to reduce the impact of frequency-selective fading, thereby improving communication reliability to some extent. However, with the increasing complexity of communication environments, the limitations of traditional OFDM technology are becoming increasingly apparent. First, in multipath environments, OFDM must add redundant cyclic prefixes (CP) to resist inter-symbol interference, which not only reduces spectrum utilization but also increases unnecessary latency overhead. Second, OFDM's pulse shaping characteristics using rectangular time-domain windows result in significant out-of-band spectrum leakage. In practical power IoT scenarios, frequency bandwidth is very limited, and with the massive influx of devices, spectrum resources are becoming increasingly scarce. This makes it difficult to meet the stringent high-reliability (99.999%) communication requirements of new power systems for massive nodes. Summary of the Invention

[0004] Therefore, to address the aforementioned shortcomings, this invention provides a power Internet of Things (IoT) communication system and signal processing method based on FBMC and micro-timeslot frequency hopping, leveraging the high spectral efficiency of FBMC, the high robustness of frequency hopping technology, and the flexible scheduling advantages of micro-timeslots. By jointly designing FBMC, micro-timeslots, and frequency hopping retransmission mechanisms, the system eliminates cyclic prefixes, enhances anti-pulse interference capabilities, and reduces the retransmission delay of power control information.

[0005] On the one hand, the present invention provides a power Internet of Things communication system based on FBMC and micro-slot frequency hopping, including a physical layer signal processing module, which includes a transmitting end signal processing module and a receiving end signal processing module; The transmitting end signal processing module includes: Serial-to-parallel conversion unit, used to convert data into parallel data. N f Parallel transmission on each subcarrier; The symbol mapping unit is used to map QAM symbols to O-QAM format, with the real and imaginary parts alternately mapped to adjacent subcarriers; The synthesis filter bank, consisting of IFFT and Hermite prototype filters, is used to synthesize the mapped data into the final FBMC time-domain transmit signal; A frequency hopping modulator, applied to the IFFT, is used to shift FBMC subcarriers into a spectrum controlled by the frequency hopping sequence; The receiving end signal processing module includes: The filter bank is analyzed, consisting of FFT and Hermite prototype filters, and is used for FBMC signal demodulation. The de-hopping unit, which operates on the FFT, is used to move the frequency-hopping signal back to the intermediate frequency / baseband while ensuring transmission and reception synchronization. The demapping unit is used for O-QAM demapping to restore the real / imaginary data.

[0006] Optionally, the power IoT communication system based on FBMC also includes a MAC layer FH / FBMC and micro-timeslot fusion module and a hybrid frequency hopping retransmission module. The FH / FBMC and micro-timeslot fusion module is used to combine the frequency domain processing capability of FBMC with the time domain flexibility of micro-timeslots; The hybrid frequency hopping retransmission module is used to fuse and transform the data into actual reliable low-latency transmission.

[0007] The aforementioned power IoT communication system based on FBMC is a high-reliability, low-latency power communication system (FH / FBMC uRLLc power communication private network) based on hybrid frequency hopping retransmission using filter bank multicarrier (FBMC) signals. Filter bank multicarrier (FBMC) technology, by introducing carefully designed prototype filter banks (such as Hermit filters), exhibits excellent energy concentration characteristics in the time and frequency domains. Compared to OFDM technology, FBMC achieves efficient transmission without the need for a cyclic prefix, significantly improving spectral efficiency and effectively suppressing multipath interference.

[0008] On the other hand, the present invention also provides a power Internet of Things communication processing method based on FBMC and micro-slot frequency hopping, including: S100, signal processing at the transmitting end; The signal processing at the transmitting end includes: S110, the serial bit stream, after channel coding, is mapped to S / P conversion. N f One parallel subcarrier; S120, The real and imaginary parts of each transmitted O-QAM symbol are alternately mapped to adjacent subcarriers; S130, multi-carrier modulation is achieved via IFFT, and pulse shaping is performed using a Hermite prototype filter. The Hermite-based prototype filter is represented as follows: ; Where g( t () is the prototype filter. T 0 Indicates the time scale parameter. H n (⋅) is the first n Hermite polynomial of order 1 n Indicates the sub-channel index number. a n It is a coefficient. t It is a time variable; S140, According to the frequency hopping sequence control, the first... n Each subcarrier was moved to the actual operating frequency; S150, after multipath fading and the AWGN channel, the received signal at the receiving end is represented as a superposition of multi-user signals.

[0009] Optionally, in step S130, H n (⋅) is the first n Hermite polynomial of order 1, expressed as: ; x It is an arbitrary variable, namely the prototype filter g( t )middle .

[0010] Optionally, in step S150, the received signal at the receiving end is represented as a superposition of multi-user signals, and the superimposed signal is represented as follows: ; in, P Indicates the number of multipaths. and They represent the first u The user in the first p Channel impulse response and delay on each path, This represents Gaussian additive white noise.

[0011] Optionally, the power IoT communication processing method based on FBMC further includes: S200, Receiver signal processing; The receiver signal processing method is as follows: Assuming the frequency hopping transceiver is synchronized, the output signal of the de-hopping unit is: A matched filter is applied to each subcarrier, and then each subcarrier is de-hopped. Then the... k After subcarrier matched filtering and sampling, we can obtain: ; Again OQAM demodulation is performed to obtain the final output signal.

[0012] Optionally, the power IoT communication processing method based on FBMC and micro-timeslot frequency hopping further includes: S300, FH / FBMC and micro-slot fusion processing, this step S300 is on the MAC layer, the specific processing method is as follows: Let the length of a micro-slot be L One FBMC symbol, one FBMC has N f The subcarrier, the u The user in the first m FBMC at the 1st moment n Each actual working subcarrier is composed of a frequency hopping sequence. control; exist i Time users p In sub-channel l The actual operating subcarrier frequency of the above frequency point for: ; in, f n = nN h f d Indicates the first n The operating frequency of the first subcarrier of each subchannel f d Indicates the subcarrier spacing; Indicates the frequency point affected by frequency hopping Controlled offset frequency; For different users u Frequency hopping sequence set Each frequency point in the algorithm is generated in a way that satisfies the conditions of being independent and uniformly distributed.

[0013] Optionally, the power IoT communication processing method based on FBMC and micro-slot frequency hopping also includes S400 and low-latency hybrid frequency hopping retransmission based on micro-slots. Step S400 is at the MAC layer, and the specific processing method is as follows: S410. Enter initialization. The communication system (power IoT communication system based on FBMC and micro-timeslot frequency hopping) completes the following three configurations: Configuration 1: Based on the data volume, set the number of symbols in the micro-slot and the number of FBMC subcarriers; Configuration 2: Define the maximum number of retransmissions as the termination threshold for retransmission operations; Configuration 3: Initialize the current retransmission count, with an initial value of 0, to record the number of subsequent retransmission actions; S420. After initialization is complete, the sending end performs a data packet sending operation. After the receiving end successfully receives the data packet, it enters the CRC check stage. CRC check is a data integrity verification, which determines whether bit errors have occurred during data transmission by comparing the check code. If the verification result is correct (ACK response), the data is complete and error-free. The receiving end directly enters the data content restoration stage, parses and restores the original data, and the process ends normally. If the CRC check fails, i.e., a NACK response is received, then an error has occurred in the data transmission and a retransmission mechanism needs to be triggered. S430. When the receiver sends back a NACK signal, the communication system (the power IoT communication system based on FBMC) automatically increments the current retransmission count by 1, records one retransmission attempt, and then enters the retransmission count determination stage, comparing the previous retransmission count with the maximum retransmission count: If the number of retransmissions exceeds the maximum number of retransmissions, the number of retransmissions reaches the limit, and the receiving end receives the erroneous data packet. If the number of previous retransmissions does not exceed the maximum number of retransmissions, the communication system (power IoT communication system based on FBMC and micro-timeslot frequency hopping) will update the data packet retransmission frequency slot through frequency hopping technology and wait for the next micro-timeslot to retransmit the data packet; After the update is complete, the process returns to the sending end to re-execute the new data packet sending operation.

[0014] The above method combines frequency hopping (FH) technology with mini-slot scheduling mechanism. Frequency hopping technology utilizes frequency diversity to enable signals to dynamically jump out of frequency bands with severe interference, while mini-slot scheduling can adaptively optimize the data frame structure by refining the granularity of time domain resource allocation, which significantly reduces retransmission waiting latency.

[0015] The present invention has the following advantages: This invention proposes using a real orthogonal prototype filter (FBMC) to replace the traditional OFDM rectangular window in a power IoT communication system, and integrates FH technology to form an FH / FBMC power IoT communication scheme. The Hermite prototype filter design exhibits excellent time-frequency localization characteristics. Hybrid frequency hopping technology is combined to utilize frequency diversity characteristics to avoid interference bands. Compared with traditional OFDM-based power IoT communication, the time-frequency localization characteristics of FBMC signals suppress multipath interference, while out-of-band leakage suppression eliminates the need for guard intervals between subcarriers. The coordinated design of FBMC modulation and frequency hopping completely eliminates the cyclic prefix requirement, improving the system's spectral efficiency and anti-interference capability (reliability).

[0016] At the communication MAC layer, the FH / FBMC signal is integrated with micro-slot frequency hopping retransmission. This scheme abandons the traditional fixed-length frame structure and flexibly selects parameters such as micro-slot length, number of subcarriers, and subcarrier spacing based on the size of the burst data. During retransmission, the FBMC subcarriers used change according to the frequency hopping sequence, ensuring interference avoidance during retransmission and reducing retransmission delay. Under complex operating conditions (multi-user access, complex interference), the FH / FBMC high-reliability low-latency power grid communication scheme of this invention significantly outperforms the traditional OFDM method in terms of bit error rate performance and delay control. Attached Figure Description

[0017] Figure 1 This is a micro-slot structure diagram of 5G / B5G NR uRLLc; Figure 2 This is a block diagram of FH / FBMC-OQAM transmission and reception; Figure 3 This is a schematic diagram of a micro-slot frequency hopping time-frequency resource scheduling and retransmission scheme based on FH / FBMC signals; Figure 4 It is based on the packet retransmission determination process in micro-slot scheduling; Figure 5 This is a comparison chart of the transmission performance of the proposed transmission scheme under multi-tone interference conditions and the traditional FH / OFDMA transmission scheme; Figure 6 This is a comparison chart of the block error rate performance of the proposed transmission scheme and the traditional FH / OFDMA transmission scheme under different retransmission counts. Detailed Implementation

[0018] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0019] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0020] To overcome the deficiencies described in the background art, this embodiment provides a power Internet of Things communication system based on FBMC and micro-slot frequency hopping, including a signal processing module at the material layer, which includes a transmitting end signal processing module and a receiving end signal processing module; The transmitting end signal processing module includes: Serial-to-parallel conversion unit, used to convert data into parallel data. N f Parallel transmission on each subcarrier; The symbol mapping unit is used to map QAM symbols to O-QAM format, with the real and imaginary parts alternately mapped to adjacent subcarriers; The synthesis filter bank, consisting of IFFT and Hermite prototype filters, is used to synthesize the mapped data into the final FBMC time-domain transmit signal; A frequency hopping modulator, applied to the IFFT, is used to shift FBMC subcarriers into a spectrum controlled by the frequency hopping sequence; The receiving end signal processing module includes: The filter bank is analyzed, consisting of FFT and Hermite prototype filters, and is used for FBMC signal demodulation. The de-hopping unit, which operates on the FFT, is used to move the frequency-hopping signal back to the intermediate frequency / baseband while ensuring transmission and reception synchronization. The demapping unit is used for O-QAM demapping to restore the real / imaginary data.

[0021] For example, such as Figure 2 As shown, the power Internet of Things (IoT) communication system based on FBMC and micro-timeslot frequency hopping mainly includes: Serial-to-parallel conversion (S / P): Converting data to parallel format (S / P). N f Parallel transmission on each subcarrier.

[0022] M-QAM to O-QAM mapping.

[0023] The Synthesis Filter Bank (SFB) consists of two processing steps: IFFT and group filtering. The group filtering process in the SFB uses a polyphase filter, which is the core module of the FBMC modulated signal.

[0024] Frequency hopping modulation / demodulation: Frequency hopping modulation shifts the FBMC subcarriers to a spectrum controlled by the frequency hopping sequence, while simultaneously avoiding interference signals. The transmitting and receiving frequency hopping sequences are assumed to be fully synchronized; dehopping moves the signal in the corresponding spectrum back to the intermediate frequency or baseband.

[0025] The Analysis Filter Bank (AFB) consists of two processes: the FFT process and the group filter process. This is the core module of FBMC demodulation.

[0026] Furthermore, the power IoT communication system based on FBMC and micro-timeslot frequency hopping also includes, The FH / FBMC and micro-slot frequency hopping fusion module is used to combine the frequency domain processing capability of FBMC with the time domain flexibility of micro-slots. The hybrid frequency hopping retransmission module is used to fuse and transform the data into actual reliable low-latency transmission.

[0027] The aforementioned power IoT communication system based on FBMC and micro-slot frequency hopping is an FH / FBMC uRLLc power communication private network system, which fully leverages the high spectral efficiency of FBMC, the high robustness of frequency hopping technology, and the flexible scheduling advantages of micro-slots. By jointly designing FBMC, micro-slots, and frequency hopping retransmission mechanisms, the system eliminates cyclic prefixes, enhances anti-pulse interference capabilities, and reduces the retransmission delay of power control information. Under complex operating conditions with multiple users, this scheme significantly outperforms traditional OFDM modulation in terms of bit error rate performance and delay control, providing a more efficient and deterministic signal transmission guarantee for the evolution of future new power systems.

[0028] This invention also provides a power Internet of Things (IoT) communication processing method based on FBMC and micro-slot frequency hopping, including: S100, Transmitter signal processing; The signal processing at the transmitting end includes: S110, the serial bit stream, after channel coding, is mapped to S / P conversion. N f One parallel subcarrier; S120, The real and imaginary parts of each transmitted O-QAM symbol are alternately mapped to adjacent subcarriers; S130, multi-carrier modulation is achieved via IFFT, and pulse shaping is performed using a Hermite prototype filter. S140, According to the frequency hopping sequence control, the first... n Each subcarrier was moved to the actual operating frequency; S150, after multipath fading and the AWGN channel, the received signal at the receiving end is represented as a superposition of multi-user signals.

[0029] For example, the entire signal processing process at the transmitting end is as follows: Assume the number of users connected to the system is N u Send at the same time M There are FBMC symbols, and the time width of each FBMC symbol is T FBMC symbol contains N f The frequency domain contains adjacent subcarriers, with [number] frequency domains. N h A frequency hopping point. For example Figure 4 As shown, at the sending end user u After being channel-coded, the transmitted serial bit data is mapped serially to parallel onto FBMC symbols. The real and imaginary parts of each transmitted OQAM symbol are alternately mapped to adjacent subcarriers, and its transmitting signal can be represented as: ; in, Indicates user u In the m The set of subcarriers used within a time period, and ; n Indicates the sub-channel index number; Represents the subcarrier frequency determined by the frequency hopping sequence; g( t () is used as a prototype filter to satisfy time-frequency locality. Represents the real part of the O-QAM signal. This represents the imaginary part of the O-QAM signal. Phase. .

[0030] The prototype filter chosen is the Hermite prototype filter. Hermite filters have a shorter time-domain response, meaning less signal delay during transmission, making them suitable for low-latency transmission applications. The prototype filter based on the Hermite polynomial is expressed as: ; Among them, the coefficients are: a 0 = 1.412692577, a 12 =-2.3611×10 -9 ; a4 = -3.0145 × 10 -3 , a 16 =-4.4570×10 -15 ; a 8 = -8.8041 × 10 -6 , a 20 =1.8633×10 -16 ; in T 0 This represents the time scale parameter, which depends on the desired subcarrier spacing (or time interval). H n (⋅) No. n The Hermite polynomial of order 1 is represented as: ; After multipath fading and the AWGN channel, the received signal at the receiver can be represented as a superposition of multiple user signals: ; in, P Indicates the number of multipaths. and They represent the first u The user in the first p Channel impulse response and delay on each path. This represents Gaussian additive white noise.

[0031] S200, receiver signal processing; The signal processing method at the receiving end is as follows: At the receiving end, assuming that the frequency hopping transceiver is synchronized, the output signal of the de-hopping unit is: First, a matched filter is used to perform matched filtering (FBMC demodulation) on each subcarrier, and then each subcarrier is de-hopped. Then the... k After subcarrier matched filtering and sampling, we can obtain: ; Finally, formula and Substitute the formula to simplify, then... OQAM demodulation is performed to obtain the final output signal.

[0032] S300, FH / FBMC and micro-slot frequency hopping fusion processing, this step of S300 is on the MAC layer, the specific processing method is as follows: From the perspective of time-frequency domain resource scheduling Figure 3A design scheme for the fusion of FH / FBMC subcarrier and symbol time slot allocation (time-frequency resources) in this system is presented. Assume a micro-time slot length is... L Each FBMC symbol can be used depending on the data traffic volume. L Values ​​can be flexibly configured ( L ={1,2,…,13} FBMC symbols. The figure shows the number of symbols in the uplink and downlink frames. L =2). One FBMC has N f The subcarrier, the u The user in the first m FBMC at the 1st moment n Each actual working subcarrier is composed of a frequency hopping sequence. Controlled, this frequency hopping strategy can employ pseudo-random number generation. Since each sub-channel contains... N h Frequency intervals f d The subcarriers, then in i Time users p In sub-channel l The actual operating subcarrier frequency of the above frequency point for ; in, Indicates the first n The operating frequency of the first subcarrier of each subchannel f d Indicates the subcarrier spacing; Indicates the frequency point affected by frequency hopping The controlled offset frequency. For different users... u Frequency hopping sequence set Each frequency point in the algorithm is generated independently and uniformly distributed.

[0033] When the reliability of symbol transmission within a micro-time slot decreases and fails to meet the transmission requirements of distribution network control services, retransmission can be quickly performed in the next micro-time slot without waiting for the next subframe (10ms) to start retransmission, thus significantly reducing transmission delay.

[0034] S400, low-latency hybrid frequency hopping retransmission based on micro-slots, this step S400 is at the MAC layer, and the specific processing method is as follows: S410. Enter initialization. The communication system (power IoT communication system based on FBMC and micro-timeslot frequency hopping) completes the following three configurations: Configuration 1: Set the number of symbols per micro-slot based on the data volume. L Value), Number of FBMC subcarriers ( N fvalue); Configuration 2: Define the maximum number of retransmissions (Max_retra) as the termination threshold for retransmission operations to avoid infinite retransmissions due to poor link quality, which would consume system resources. Configuration 3: Initialize the current retransmission count (Index_retra). The initial value is usually 0, which is used to record the number of subsequent retransmissions. S420. After initialization is completed, the sending end performs data packet sending operation (specifically as in steps S110-S150). After the receiving end successfully receives the data packet, it enters the CRC check stage. CRC check is a data integrity verification, which determines whether bit errors have occurred during data transmission by comparing the check code. If the verification result is correct (ACK response), the data is complete and error-free. The receiving end directly enters the data content restoration stage, parses and restores the original data, and the process ends normally. If the CRC check fails, i.e., a NACK response is received, then an error has occurred in the data transmission and a retransmission mechanism needs to be triggered. S430. When the receiver sends back a NACK signal, the communication system (a power IoT communication system based on FBMC and micro-timeslot frequency hopping) automatically increments the current retransmission count by 1, records one retransmission attempt, and then enters the retransmission count determination stage, comparing the previous retransmission count Index_retra with the maximum retransmission count Max_retra: If the previous retransmission count Index_retra exceeds the maximum retransmission count Max_retra, then the retransmission count has reached the limit, and the receiving end receives the erroneous data packet. If the previous retransmission count Index_retra does not exceed the maximum retransmission count Max_retra, the communication system (power IoT communication system based on FBMC and micro-timeslot frequency hopping) will update the data packet retransmission frequency slot through frequency hopping technology; and wait for the next micro-timeslot to retransmit the data packet; the probability of retransmission error is reduced by frame frequency hopping, and the retransmission waiting time is reduced by micro-timeslot retransmission.

[0035] After the update is complete, the process returns to the sending end to re-execute the new data packet sending operation.

[0036] The following simulation experiments demonstrate the technical advantages of the power IoT communication processing based on FBMC and micro-slot frequency hopping fusion (i.e., the FH / FBMC uRLLc system) proposed in this embodiment in the power IoT scenario. The system parameters are set as follows: number of subcarriers... N f =32, Number of user frequency hopping slots N h=60, and the prototype filter adopts the Hermite orthogonal polynomial filter with excellent delay characteristics. The channel model is the TDL delay line model with multipath delay spread and Doppler shift defined by the 3GP PTR 38.901 standard. Reliability (bit error rate and block error rate), transmission delay (number of retransmissions), and anti-interference capability were simulated and verified, and the simulation results were analyzed accordingly. For comparative analysis, the FH / OFDMA transmission scheme including CP was used as a performance comparison.

[0037] Test 1: Single-shot point-to-point bit error rate analysis (reliability verification); Total number of frequency hopping slots N h At 60°C, for multi-tone interference, a 10% frequency slot is set as the interference slot, with an interference power of 0dB. The transmission performance of the proposed transmission scheme under multi-tone interference is compared with that of the traditional FH / OFDMA transmission scheme. Figure 3 As shown. The transmission performance under pulse interference is compared as follows: Figure 5 As shown. Test 1 is the transmission reliability of a single point-to-point FH / FBMC, without considering retransmission mechanisms.

[0038] Under 10% bandwidth multi-tone interference, the orthogonality of traditional FH / OFDMA is easily compromised, resulting in a relatively high bit error rate. However, this proposed solution, with its strong out-of-band suppression capability of the filter bank, maintains a low block error rate even in the high signal-to-noise ratio region (SNR>30dB), demonstrating a significant leading advantage. This invention employs a two-dimensional time-frequency interference suppression mechanism using FBMC and frequency hopping to disperse pulse energy in the time domain and limit interference propagation in the frequency domain. This results in superior anti-interference performance after SNR>20dB, with a significantly reduced block error rate.

[0039] Conclusion: The proposed transmission scheme exhibits superior anti-interference performance under multi-tone interference conditions. It can be seen that the enhanced frequency-hopping (FBMC) transmission scheme based on micro-slot retransmission proposed in this patent significantly improves the performance boundary in ultra-reliable low-latency communication (URLLC) scenarios through a cyclic prefix-free (CP) architecture and random frequency hopping.

[0040] Test 2: Verification of "Reliability (Block Error Rate) - Delay (Number of Retransmissions)" under Micro-Slot Frequency Hopping Retransmission Mechanism; Figure 6 This shows the block error rate (BLER) as a function of the number of retransmissions. N The changing relationships aim to verify the system's ability to support low-latency, millisecond-level latency services in the power sector.

[0041] Simulation results show that the block error rate decreases with increasing retransmission count, and the block error rate can be lower than 10 when the number of retransmissions reaches N=4 and the SNR≥20dB. -6(Guaranteeing target reliability >99.999%). Here, all four retransmissions are performed within a micro-timeslot. Specific transmission delays and the number of symbols within a micro-timeslot are also considered. L and FBMC subcarrier spacing f d Select closely related, for example, when f d =15 kHz, L When =7, the width of a single micro-timeslot is T mini-slot =0.5ms, a single subframe in a traditional FH / OFDM system T sub-frame =1ms. Considering the time slot occupied by the receiver transmitting NACK / ACK information back to the sender, the total transmission delay is approximately 2. NT mini-slot That is, the FH / FBMCuRLLc system has a latency of 4ms, while the traditional subframe FH / OFDM system has a latency of 8ms. Therefore, for the micro-slot FH / FBMC system, a transmission success rate of 99.999% can be achieved with fewer retransmissions (N=4, short retransmission delay).

[0042] Conclusion: The proposed micro-slot and FH / FBMC fusion scheme has good interference suppression gain and flexible retransmission scheduling. It can meet the millisecond-level latency constraints of power Internet of Things communication while ensuring the target reliability (>99.999%).

[0043] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power Internet of Things communication system based on FBMC and micro-timeslot frequency hopping, characterized in that, The signal processing module includes a physical layer, which includes a transmitting end signal processing module and a receiving end signal processing module. The transmitting end signal processing module includes: Serial-to-parallel conversion unit, used to convert data into parallel data. N f Parallel transmission on each subcarrier; The symbol mapping unit is used to map QAM symbols to O-QAM format, with the real and imaginary parts alternately mapped to adjacent subcarriers; The synthesis filter bank, consisting of IFFT and Hermite prototype filters, is used to synthesize the mapped data into the final FBMC time-domain transmit signal; A frequency hopping modulator, applied to the IFFT, is used to shift FBMC subcarriers into a spectrum controlled by the frequency hopping sequence; The receiving end signal processing module includes: The filter bank is analyzed, consisting of FFT and Hermite prototype filters, and is used for FBMC signal demodulation. The de-hopping unit, which operates on the FFT, is used to move the frequency-hopping signal back to the intermediate frequency / baseband while ensuring transmission and reception synchronization. The demapping unit is used for O-QAM demapping to restore the real / imaginary data.

2. The power Internet of Things communication system based on FBMC and micro-timeslot frequency hopping according to claim 1, characterized in that, It also includes a MAC layer FH / FBMC and micro-slot fusion module and a hybrid frequency hopping retransmission module. The FH / FBMC and micro-timeslot fusion module is used to combine the frequency domain processing capability of FBMC with the time domain flexibility of micro-timeslots; The hybrid frequency hopping retransmission module is used to fuse and transform the data into actual reliable low-latency transmission.

3. A power IoT communication processing method based on FBMC and micro-timeslot frequency hopping, characterized in that... include: S100, Transmitter signal processing; The signal processing at the transmitting end includes: S110, the serial bit stream, after channel coding, is mapped to S / P conversion. N f One parallel subcarrier; S120, The real and imaginary parts of each transmitted O-QAM symbol are alternately mapped to adjacent subcarriers; S130, multi-carrier modulation is achieved via IFFT, and pulse shaping is performed using a Hermite prototype filter. The Hermite-based prototype filter is represented as follows: ； Where g( t () is the prototype filter. T 0 Indicates the time scale parameter. H n (⋅) is the first n Hermite polynomial of order 1 n Indicates the sub-channel index number. a n It is a coefficient. t It is a time variable; S140, According to the frequency hopping sequence control, the first... n Each subcarrier was moved to the actual operating frequency; S150, after multipath fading and the AWGN channel, the received signal at the receiving end is represented as a superposition of multi-user signals.

4. The power Internet of Things communication processing method based on FBMC and micro-timeslot frequency hopping according to claim 3, characterized in that, In step S130, H n (⋅) is the first n Hermite polynomial of order 1, expressed as: ； x It is an arbitrary variable, namely the prototype filter g( t )middle .

5. The power Internet of Things communication processing method based on FBMC and micro-timeslot frequency hopping according to claim 4, characterized in that, In step S150, the received signal at the receiving end is represented as a superposition of multi-user signals, and the superimposed signal is represented as follows: ； in, P Indicates the number of multipaths. and They represent the first u The user in the first p Channel impulse response and delay on each path, This represents Gaussian additive white noise.

6. The power IoT communication processing method based on FBMC and micro-timeslot frequency hopping according to claim 5, characterized in that, It also includes S200 and receiver signal processing; The signal processing method at the receiving end is as follows: Assuming the frequency hopping transceiver is synchronized, the output signal of the de-hopping unit is: ; A matched filter is applied to each subcarrier, and then each subcarrier is de-hopped. Then the... k After subcarrier matched filtering and sampling, we can obtain: ； Again OQAM demodulation is performed to obtain the final output signal.

7. The power Internet of Things communication processing method based on FBMC and micro-timeslot frequency hopping according to claim 3 or 6, characterized in that, Also includes: S300, FH / FBMC and micro-slot fusion processing, this step S300 is on the MAC layer, the specific processing method is as follows: set up A micro-slot length is L One FBMC symbol, one FBMC has N f The subcarrier, the u The user in the first m FBMC at the 1st moment n Each actual working subcarrier is composed of a frequency hopping sequence. control; exist i Time users p In sub-channel l The actual operating subcarrier frequency of the above frequency point for: ； in, f n = nN h f d Indicates the first n The operating frequency of the first subcarrier of each subchannel f d Indicates the subcarrier spacing; Indicates the frequency point affected by frequency hopping Controlled offset frequency; For different users u Frequency hopping sequence set Each frequency point in the algorithm is generated in a way that satisfies the conditions of being independent and uniformly distributed.

8. The power Internet of Things communication processing method based on FBMC and micro-timeslot frequency hopping according to claim 7, characterized in that, It also includes S400 and low-latency hybrid frequency hopping retransmission based on micro-slots. This step, S400, is at the MAC layer, and the specific processing method is as follows: S410. Enter initialization. The communication system completes the following three configurations: Configuration 1: Based on the data volume, set the number of symbols in the micro-slot and the number of FBMC subcarriers; Configuration 2: Define the maximum number of retransmissions as the termination threshold for retransmission operations; Configuration 3: Initialize the current retransmission count, with an initial value of 0, to record the number of subsequent retransmission actions; S420. After initialization is complete, the sending end performs a data packet sending operation. After the receiving end successfully receives the data packet, it enters the CRC check stage. CRC check is a data integrity verification, which determines whether bit errors have occurred during data transmission by comparing the check code. If the verification result is correct (ACK response), the data is complete and error-free. The receiving end directly enters the data content restoration stage, parses and restores the original data, and the process ends normally. If the CRC check fails, i.e., a NACK response is received, then an error has occurred in the data transmission and a retransmission mechanism needs to be triggered. S430. When the receiver sends back a NACK signal, the communication system automatically increments the current retransmission count by 1, records one retransmission attempt, and then enters the retransmission count determination stage, comparing the previous retransmission count with the maximum retransmission count: If the number of retransmissions exceeds the maximum number of retransmissions, the number of retransmissions reaches the limit, and the receiving end receives the erroneous data packet. If the previous retransmission count has not exceeded the maximum retransmission count, the communication system will update the data packet retransmission frequency slot through frequency hopping technology and wait for the next micro-time slot to retransmit the data packet. After the update is complete, the process returns to the sending end to re-execute the new data packet sending operation.

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