Dual-mode communication diversity sending method and system

Abstract

The invention discloses a dual-mode communication diversity transmission method and system, and belongs to the technical field of communication, and the method comprises the steps: firstly carrying out the phase line division of a CSMA time slot bound with an HRF, then carrying out the set division of the HRF transmission frequency of a terminal of the same phase line, determining the HRF transmission frequency of the terminal through static distribution or dynamic distribution, and completing the diversity transmission of communication. The technical problem of rate mismatching in the dual-mode communication process in the prior art is solved.

Description

Technical Field

[0001] The present invention belongs to the field of communication technology, and in particular relates to a dual-mode communication diversity transmission method and system. Background Art

[0002] In 2020, the China Electric Power Research Institute released the HPLC+HRF dual-mode communication standard, requiring support for dual-mode communication with dual transmission and reception, that is, the ability to perform HPLC and HRF transmission and reception at the same time. Dual-mode communication can meet the requirements of the "new power system" business scenario for larger communication bandwidth, higher speed and higher reliability, and has become one of the key communication technologies in the low-voltage power grid field. The physical layer of the HPLC and wireless parts of the dual-mode standard both use OFDM modulation, and also use the same architecture of Turbo coding and copy interleaving technology. The difference is that HPLC has a higher sampling rate and wider bandwidth, while the wireless communication bandwidth is narrower, there is a rate mismatch problem, and transmit diversity cannot be performed. Summary of the Invention

[0003] To address the problem of mismatch between wired transmission and wireless transmission speeds in the prior art, the present invention proposes a dual-mode communication diversity transmission method, comprising the following steps: Step 1: Phase line division of the CSMA time slot bound to the HRF; Step 2: Divide the HRF transmission frequency into sets; Step 3: Determine the terminal HRF transmission frequency by static allocation, dynamic allocation, or sending in advance; Step 4: HPLC first receives the signal, then performs decoding and CRC check to complete data transmission.

[0004] Preferably, in step 1, the phase line division is performed based on the HPLC phase line corresponding to the same terminal as the HRF.

[0005] Preferably, in step 1, the terminal located on the A-phase line of the HPLC will transmit data from the A-phase line of the HRF during wireless communication transmission; The terminal located on the B-phase line of HPLC will transmit data from the B-phase line of HRF during wireless communication transmission; The terminal located on the C-phase line of HPLC will send data from the C-phase line of HRF during wireless communication transmission.

[0006] Preferably, in step 2, the HRF transmission frames of different terminals are overlapped in time by dividing the transmission frequency set, and the HPLC transmission is performed using CSMA access. Once the HPLC starts to transmit, the HRF is transmitted synchronously with the HPLC in time.

[0007] Preferably, in step 3, when static allocation is used to determine the terminal HRF transmission frequency: First, assume that HRF has N available frequencies, namely f1, f2..., f N , and divide the HRF frequencies into three sets: {f1, f4...f N-2}, {f2, f5...f N-1} and {f3, f6...f N}, corresponding to the transmission frequencies of phase A, phase B and phase C respectively; Next, the frequencies within the A / B / C phase frequency set are used in sequence. The HRF packet corresponding to the first HPLC data packet in phase A is transmitted at frequency f1, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f4, ...; the HRF packet corresponding to the first HPLC data packet in phase B is transmitted at frequency f2, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f5, ...; the HRF packet corresponding to the first HPLC data packet in phase C is transmitted at frequency f3, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f6, ...; Finally, the A / B / C phases are divided into floor (phase line length / hplc shortest frame length) time slots, each of which corresponds to a frequency; floor (.) indicates rounding down.

[0008] Preferably, in step 3, when dynamic allocation is used to determine the terminal HRF transmission frequency, the following operations are performed: First, the first user randomly selects a sending frequency or determines the sending frequency based on historical sending experience; Then the next user detects the transmission frequency of the previous user and staggers the frequency by m, where m>2.

[0009] Preferably, in step 3, when the terminal HRF transmission frequency is determined by advance transmission: Assuming that HPLC is estimated to be at t hplc , t hplc That is, the HPLC sending time, t hplc The length of the sent packet is L hplc , the length of HRF's sending packet is L hrf , then the HRF sending advance is: Delta_t = t hplc -(L hrf -L hplc ) The transmission frequency of HRF is divided according to time slots, and the shortest frame length of HRF is used as the time slot length. Assuming that the time slot length is T slot, then the number of time slots that a phase line can be divided into is: floor(T phase / T slot ); the transmission frequency of the first time slot is f1, ..., the floor(T phase / T slot ) The transmission frequency of the time slot is: f mod(floor(Tphase / Tslot) / N)+1 ;T phase Represents the phase line length, and N represents a random natural number.

[0010] Preferably, in step 4, HPLC first completes signal reception, and then performs decoding and CRC check; if the CRC check passes, the signal data transmission is completed; if the check fails, LLR is combined with the received data of HRF, and the combined data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the transmission fails.

[0011] A dual-mode communication diversity transmission system includes the following modules: Phase line division module: divides the CSMA time slot of HRF into three time slots: A, B, and C; Transmit frequency division module: divides the HRF transmission frequency into sets, allowing the HRF transmission frames of different terminals to overlap in time through the transmission frequency set division; Terminal sending module: adopts static allocation, dynamic allocation and advance sending to determine the HRF sending frequency; CRC check module: HPLC receives the sent HPLC signal, then decodes and performs CRC check on the received HPLC signal to complete the transmission of this signal data.

[0012] Preferably, in the CRC module, if the CRC check passes, the signal data transmission is completed; if the check fails, the LLR is combined with the HRF received data, and the combined data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the transmission fails.

[0013] Compared with the prior art, the technical solution of the present invention has the following advantages / benefits: 1. The present invention improves the transmission rate of wireless communication by modifying the time slot division method of the HRF MAC layer, thereby improving the transmission efficiency and reliability of the dual-mode communication system.

[0014] 2. The present invention determines the terminal HRF transmission frequency through static allocation, dynamic allocation and advance transmission, thereby reducing HRF collisions and improving the efficiency of wireless communication.

[0015] 3. The present invention divides the CSMA time slot of HRF into phase lines, thereby reducing the number of terminals transmitting HRF in the phase line, reducing the probability of conflict, and improving the transmission efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is the dual-mode protocol time slot division diagram used in the present invention.

[0018] Figure 2 This is the HRF time slot division diagram used in the present invention.

[0019] Figure 3 The invention relates to a flow chart of a dual-mode communication diversity transmission method.

[0020] Figure 4 It is a framework diagram of a dual-mode communication diversity transmission system. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the detailed description of the embodiments of the present invention provided below is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it may not be further defined or explained in subsequent drawings.

[0023] Example 1: Figure 1 As shown in the figure, in the State Grid dual-mode protocol, since the terminals are distributed on different phase lines, the CSMA time slots of HPLC and the bound CSMA time slots are divided according to the three phase lines A, B, and C. However, for the CSMA time slots and the bound CSMA time slots of HRF, there is no concept of phase lines, and the CSMA time slots and the bound CSMA time slots are not divided by phase lines.

[0024] like Figure 3As shown, the present invention provides a dual-mode communication diversity transmission method, comprising the following steps: Step 1: Phase line division of the CSMA time slot bound to the HRF; Step 2: Divide the HRF transmission frequency set of the terminals on the same phase line; Step 3: Determine the terminal HRF transmission frequency by static allocation, dynamic allocation, or advance transmission; Step 4: HPLC first receives the signal, then performs decoding and CRC check to complete data transmission.

[0025] Phase line division is based on the HPLC phase line corresponding to the same terminal of the HRF.

[0026] like Figure 2 As shown, in step 1, the CSMA time slot bound to the HRF is phase-line divided, and the HRF is divided into three time slots A, B, and C.

[0027] The terminal located on the A-phase line of HPLC will transmit data from the A-phase line of HRF during wireless communication transmission; The terminal located on the B-phase line of HPLC will transmit data from the B-phase line of HRF during wireless communication transmission; The terminal located on the C phase line of HPLC will send data from the C phase line of HRF during wireless communication transmission, which reduces the number of terminals sending from HRF in the phase line and reduces the probability of conflict.

[0028] In step 2, for terminals on the same phase line, since the transmission rates of HPLC and HRF do not match, the HRF transmission frequency needs to be divided. By dividing the transmission frequency set, the HRF transmission frames of different terminals overlap in time, thereby improving the HRF throughput and making the transmission rates of HRF and HPLC close to the same at the system level. HPLC transmission adopts CSMA access. Once HPLC starts sending, HRF is sent synchronously with HPLC in time, and the HPLC transmission frequencies of different terminals are the same, while the HRF transmission frequencies are different.

[0029] In step 3, when static allocation is used to determine the terminal HRF transmission frequency: First, assume that HRF has N available frequencies, namely f1, f2..., f N , and divide the HRF frequencies into three sets: {f1, f4...f N-2}, {f2, f5...f N-1} and {f3, f6...f N}, corresponding to the transmission frequencies of phase A, phase B and phase C respectively; Next, the frequencies within the A / B / C phase frequency set are used in sequence. The HRF packet corresponding to the first HPLC data packet in phase A is transmitted at frequency f1, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f4, ...; the HRF packet corresponding to the first HPLC data packet in phase B is transmitted at frequency f2, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f5, ...; the HRF packet corresponding to the first HPLC data packet in phase C is transmitted at frequency f3, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f6, ...; Finally, considering that HPLC terminals on the same phase line may not be in the same domain, and that if HRFs are in the same domain, the terminals may not be able to detect the HPLC signals sent by other terminals, thus creating the risk of conflict, the A / B / C phases are divided into floor (phase line length / HPLC minimum frame length) time slots according to the time domain. Each time slot corresponds to a frequency; floor (.) indicates rounding down.

[0030] For example, the transmission frequency of the first time slot is fixed at: f1; the transmission frequency of the second time slot is fixed at: f4.

[0031] len_xiangxian represents the phase line (time) length; min_hplc_len represents the (time) length of the shortest HPLC frame.

[0032] The domain here represents the subnet that can communicate and hear each other. If a HPLC sends a signal and the terminal cannot hear it, the HRF may send the same frequency.

[0033] In this way, the frequency of each HRF transmission will not overlap with the previous transmission, and the difference will be at least 3 channels, avoiding adjacent channel interference and inter-channel interference, and ensuring that the mutual interference is small.

[0034] In step 3, when dynamic allocation is used to determine the terminal HRF transmission frequency: First, the first user randomly selects a sending frequency or determines the sending frequency based on historical sending experience; Then the next user detects the sending frequency of the previous user, and then based on this, staggers m frequencies. In order to avoid mutual interference, m>2 is required.

[0035] In step 3, when the terminal HRF transmission frequency is determined by advance transmission: Assuming that HPLC is estimated to be at t hplc , t hplc That is, the HPLC sending time, t hplc The length of the sent packet is Lhplc , the length of HRF's sending packet is L hrf , then the HRF sending advance is: Delta_t = t hplc -(L hrf -L hplc ) By sending in advance, the end time of HPLC and HRF frames can be made approximately the same. The transmission frequency of HRF is divided according to time slots, and the shortest frame length of HRF is used as the time slot length. Assuming the time slot length is T slot , then the number of time slots that a phase line can be divided into is: floor(T phase / T slot ); the transmission frequency of the first time slot is f1, ..., the floor(T phase / T slot ) The transmission frequency of the time slot is: f mod(floor(Tphase / Tslot) / N)+1 ;T phase Represents the phase line length, and N represents a random natural number.

[0036] In step 4, HPLC first completes signal reception, and then performs decoding and CRC check; if the CRC check passes, the signal data transmission is completed; if the check fails, the LLR is merged with the received data of HRF, and the merged data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the transmission fails.

[0037] Example 2: Figure 4 As shown, a dual-mode communication diversity transmission system includes the following modules: Phase line division module: divides the CSMA time slot of HRF into three time slots: A, B, and C; Transmit frequency division module: divides the HRF transmission frequency into sets, allowing the HRF transmission frames of different terminals to overlap in time through the transmission frequency set division; Terminal sending module: adopts static allocation, dynamic allocation and advance sending to determine the HRF sending frequency; CRC check module: HPLC receives the sent HPLC signal, then decodes and performs CRC check on the received HPLC signal to complete the transmission of this signal data.

[0038] In the CRC module, if the CRC check passes, the signal data transmission is completed; if the check fails, the LLR is combined with the HRF received data, and the combined data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the transmission fails.

[0039] Explanation of terms: HPLC is the abbreviation of High-speed Power Line Carrier. HRF is the abbreviation of High-speed Radio Frequency, CSMA is the abbreviation of Carrier Sense Multiple Access. CRC is the abbreviation of Cyclic Redundancy Check. LLR is the abbreviation of Log-Likelihood Ratio.

[0040] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. Persons skilled in the art will appreciate that improvements and modifications may be made without departing from the spirit and scope of the present invention, and such improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A dual-mode communication diversity transmission method, characterized in that: The following steps are involved: Step 1: Phase line division of the CSMA time slot bound to the HRF; Step 2: Divide the HRF transmission frequency into sets; Step 3: Determine the terminal HRF transmission frequency by static allocation, dynamic allocation, or sending in advance; Step 4: HPLC first receives the signal, then performs decoding and CRC check to complete data transmission.

2. A dual-mode communication diversity transmission method according to claim 1, characterized in that: In the step 1, the phase line division is performed based on the HPLC phase line corresponding to the same terminal as the HRF.

3. A dual-mode communication diversity transmission method and system according to claim 2, characterized in that: In the step 1, the terminal located on the A-phase line of the HPLC will transmit data from the A-phase line of the HRF during wireless communication transmission; The terminal located on the B-phase line of HPLC will transmit data from the B-phase line of HRF during wireless communication transmission; The terminal located on the C-phase line of HPLC will send data from the C-phase line of HRF during wireless communication transmission.

4. A dual-mode communication diversity transmission method according to claim 1, characterized in that: In the step 2, the HRF transmission frames of different terminals are overlapped in time by dividing the transmission frequency set. The HPLC transmission is performed by CSMA access. Once the HPLC starts to send, the HRF is sent synchronously with the HPLC in time.

5. The dual-mode communication diversity transmission method according to claim 1, characterized in that: In step 3, when static allocation is used to determine the terminal HRF transmission frequency: First, assume that HRF has N available frequencies, namely f1, f2..., f N , and divide the HRF frequencies into three sets: {f1, f4...f N-2 }, {f2, f5...f N-1 } and {f3, f6...f N }, corresponding to the transmission frequencies of phase A, phase B and phase C respectively; Next, the frequencies within the A / B / C phase frequency set are used in sequence. The HRF packet corresponding to the first HPLC data packet in phase A is transmitted at frequency f1, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f4, ...; the HRF packet corresponding to the first HPLC data packet in phase B is transmitted at frequency f2, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f5, ...; the HRF packet corresponding to the first HPLC data packet in phase C is transmitted at frequency f3, and the HRF packet corresponding to the second HPLC data packet is transmitted at frequency f6, ...; Finally, the A / B / C phases are divided into floor(phase line length / hplc shortest frame length) time slots, each of which corresponds to a frequency; floor (.) indicates rounding down.

6. A dual-mode communication diversity transmission method according to claim 1, characterized in that: In step 3, when dynamic allocation is used to determine the terminal HRF transmission frequency, the following operations are performed: First, the first user randomly selects a sending frequency or determines the sending frequency based on historical sending experience; Then the next user detects the transmission frequency of the previous user and staggers the frequency by m, where m>2.

7. A dual-mode communication diversity transmission method according to claim 1, characterized in that: In step 3, when the terminal HRF transmission frequency is determined by advance transmission: Assuming that HPLC is estimated to be at t hplc , t hplc That is, the HPLC sending time, t hplc The length of the sent packet is L hplc , the length of HRF's sending packet is L hrf , then the HRF sending advance is: Delta_t = t hplc -(L hrf -L hplc ) The transmission frequency of HRF is divided according to time slots, and the shortest frame length of HRF is used as the time slot length. Assuming that the time slot length is T slot , then the number of time slots that a phase line can be divided into is: floor(T phase / T slot ); the transmission frequency of the first time slot is f1, ..., the floor(T phase / T slot ) The transmission frequency of the time slot is: f mod(floor(Tphase / Tslot) / N)+1 ;T phase Represents the phase line length, and N represents a random natural number.

8. A dual-mode communication diversity transmission method according to claim 1, characterized in that: In step 4, the HPLC first completes the signal reception, and then performs decoding and CRC verification; if the CRC verification passes, the signal data transmission is completed; If the check fails, the LLR is combined with the HRF received data, and the combined data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the sending fails.

9. A dual-mode communication diversity transmission system, characterized in that: Includes the following modules: Phase line division module: divides the CSMA time slot of HRF into three time slots: A, B, and C; Transmit frequency division module: divides the HRF transmission frequency into sets, allowing the HRF transmission frames of different terminals to overlap in time through the transmission frequency set division; Terminal sending module: adopts static allocation, dynamic allocation and advance sending to determine the HRF sending frequency; CRC check module: HPLC receives the sent HPLC signal, then decodes and performs CRC check on the received HPLC signal to complete the transmission of this signal data.

10. A dual-mode communication diversity transmission system according to claim 9, characterized in that: In the CRC module, if the CRC check passes, the signal data transmission is completed; if the check fails, the LLR is combined with the HRF received data, and the combined data is further decoded and CRC checked. If the CRC check passes, the signal data is received correctly, otherwise the transmission fails.

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