Power line channel and wireless channel parallel access communication method, terminal, equipment and storage medium

Abstract

The invention discloses a parallel access communication method for a power line channel and a wireless channel, a terminal, equipment and a storage medium, the method is executed on a station supporting the power line channel and the wireless channel at the same time, when the station has a data packet to be sent, a power line backoff stage counter BPC and a wireless backoff stage counter BPC0 are initialized to be 0, and when the data packet is sent, the power line backoff stage counter BPC and the wireless backoff stage counter BPC0 are initialized to be 0; the value of a power line backoff counter BC is initialized according to the power line contention window value, and the value of a wireless backoff counter BC0 is initialized according to the wireless contention window value; simultaneously monitoring whether the power line channel and the wireless channel are idle or not, and if so, subtracting 1 from the back-off counter; and if the values of the BC and the BC0 both reach 0, transmitting the same data packet on the two channels at the same time, and after a returned acknowledgement frame is received, confirming that the data packet is successfully transmitted. The advantages of power line communication and wireless communication are fully utilized. The collision probability is reduced, and the data transmission success rate is improved through double-channel parallel transmission.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a power line channel and wireless channel parallel access communication method based on a fusion terminal, a terminal, a device and a storage medium. Background Art

[0002] Wireless communication technology has the characteristics of wide coverage, scalability, flexibility and openness. At present, the research focus of wireless communication is on the development and application of technologies with high maintainability, high reliability and high adaptability, aiming to provide reliable guarantee for power system communication, ensure that control information, management of various links and other related communications can achieve two-way interaction, ensure the timeliness of related operations during the operation of the power system, improve the quality and efficiency of power communication, improve the service level of the power system, and then improve the service quality of the power system and improve the safety of the service. However, when wireless communication is blocked by obstacles, the signal attenuation is serious and the communication quality is affected. Power line carrier communication has the advantages of low cost, high efficiency, high reliability, convenient networking and no need for repeated wiring. However, traditional power line carrier communication lacks methods and time compensation mechanisms that can effectively calculate time synchronization errors, and is greatly affected by electromagnetic interference.

[0003] Due to the wide application of power line and wireless communication in the fields of power Internet of Things and smart home, domestic and foreign scholars have proposed some new ideas for power line and wireless fusion communication in order to make full use of the advantages of power line carrier communication and wireless communication in dealing with different scenarios. By adopting two communication methods, when one communication method fails or is interfered, the other method can continue to maintain communication, thereby improving the reliability and stability of the overall system. The throughput and transmission probability of the system are improved by diversity technology and relay technology. Since the IEEE 1901 and IEEE802.11 standards use the same physical layer technology at the physical layer, such as OFDM (Orthogonal Frequency Division Multiplexing) and other modulation technologies. Therefore, after down-converting the radio signal, it can be merged with the power line signal under the same baseband or intermediate frequency signal processing framework, and then different relay protocols are used to forward the merged signal, making fusion communication feasible.

[0004] For power line carrier communication and wireless converged communication, a solution in the prior art provides a wireless and power line converged communication system, which has advantages in technology and construction cost compared with a single system, as well as the impact of different communication environments on the converged communication system. Another solution in the prior art provides a proposal to use the MAC (Medium Access Control) layer to realize power line and wireless converged communication, but the system needs to report channel status information to the virtual MAC layer from time to time, resulting in a significant increase in signaling overhead and low efficiency.

[0005] The above-mentioned power line carrier communication and wireless fusion communication scheme in the prior art has the following disadvantages: power line communication is susceptible to electromagnetic interference and load changes, and the channel quality is unstable. Wireless communication is susceptible to physical obstacles and reflections, and there are signal blind spots. The single channel access method cannot meet the needs of efficient and reliable communication. Summary of the invention

[0006] Purpose of the invention: The present invention provides a method, terminal, device and storage medium for parallel access of power line channels and wireless channels based on a fusion terminal, so as to effectively improve the reliability of data transmission in a wireless communication system and increase the throughput of the system.

[0007] Technical solution: In a first aspect, a method for parallel access of a power line channel and a wireless channel is provided, comprising the following steps:

[0008] When a station has a data packet to send, it initializes the power line backoff phase counter BPC and the wireless backoff phase counter BPC0, enters the backoff phase, and initializes the value of the power line backoff counter BC according to the power line contention window value, initializes the value of the wireless backoff counter BC0 according to the wireless contention window value, and initializes the power line delay counter DC;

[0009] Monitor the status of the power line channel and the wireless channel. If any channel is idle, decrement the corresponding backoff counter. If the channel is busy, freeze the corresponding backoff counter and adjust the backoff stage according to the value of the power line delay counter DC. Continue monitoring until the backoff counters of both channels are 0.

[0010] The same data packet is transmitted on the power line channel and the wireless channel, and after receiving the confirmation frame returned on either channel, the successful transmission of the data packet is confirmed.

[0011] According to some embodiments of the first aspect, initializing a value of a power line backoff counter BC according to a power line contention window value, and initializing a value of a wireless backoff counter BC0 according to a wireless contention window value, comprises:

[0012] The station starts to compete for the channel from the backoff stage (0,0). The backoff stage (i,j) indicates that the dual-interface station is in the backoff stage i in the power line channel and in the backoff stage j in the wireless channel. When the station enters the backoff stage (i,j), the value of BC is in {0,…,CW i -1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase.

[0013] According to certain embodiments of the first aspect, the site uses a carrier sense multiple access / collision avoidance protocol mechanism to monitor the power line channel and check whether the power line channel is idle; the site uses a distributed coordination function DCF to monitor the wireless channel and check whether the wireless channel is idle.

[0014] According to certain embodiments of the first aspect, the status of the power line channel and the wireless channel are monitored, and if any channel is idle, the corresponding backoff counter is decremented, and if the channel is busy, the corresponding backoff counter is frozen, and the backoff stage is adjusted according to the value of the power line delay counter, and the backoff counters of the two channels are continuously monitored until they are both 0, including:

[0015] If the power line channel is idle, the value of the power line backoff counter BC is reduced by 1. If the power line channel is busy, the value of the power line backoff counter BC is frozen, and the value of the delay counter DC is reduced by 1. If DC = 0 and the power line channel is detected to be busy again, the station directly retreats to the next stage; if the power line backoff counter BC reaches 0, the station enters the waiting state and waits for the value of the wireless backoff counter BC0 to reach 0;

[0016] If the wireless channel is idle, the value of the wireless backoff counter BC0 is reduced by 1. If the wireless channel is busy, the value of the wireless backoff counter BC0 is frozen until the channel is idle. If BC0 reaches 0, the station enters a waiting state until the value of the power line backoff counter BC reaches 0.

[0017] According to some embodiments of the first aspect, transmitting the same data packet over a power line channel and a wireless channel comprises:

[0018] When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, they wait for the specified distributed coordination function interframe interval DIFS. If the power line channel and the wireless channel are always idle during the waiting period, the station transmits the same data frame on the power line channel and the wireless channel simultaneously.

[0019] According to certain embodiments of the first aspect, the method further includes: if no confirmation frame is received on the power line channel and the wireless channel, it is determined that the transmission of the data frame has failed, the values ​​of the two backoff phase counters BPC and BPC0 are respectively increased by 1, and the power line contention window value and the wireless contention window value are reset, the values ​​of the two backoff counters BC and BC0 are reset, and the process of monitoring the power line channel and the wireless channel and resending the data frame is re-executed. In a second aspect, a fusion terminal is provided, including:

[0020] A communication initialization module is used to initialize the power line backoff phase counter BPC and the wireless backoff phase counter BPC0 when the terminal has a data packet to send, enter the backoff phase, and initialize the value of the power line backoff counter BC according to the power line contention window value, initialize the value of the wireless backoff counter BC0 according to the wireless contention window value, and initialize the power line delay counter DC;

[0021] The channel monitoring module is used to monitor the status of the power line channel and the wireless channel. If any channel is idle, the corresponding backoff counter is decremented. If the channel is busy, the corresponding backoff counter is frozen and the backoff stage is adjusted according to the value of the power line delay counter. The monitoring is continued until the backoff counters of the two channels are both 0.

[0022] The data sending module is used to transmit the same data packet on the power line channel and the wireless channel when the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, and confirm that the data packet is successfully transmitted after receiving a confirmation frame returned on either channel.

[0023] According to some embodiments of the second aspect, initializing the value of the power line backoff counter BC according to the power line contention window value, and initializing the value of the wireless backoff counter BC0 according to the wireless contention window value, comprises:

[0024] The terminal starts to compete for the channel from the backoff stage (0,0). The backoff stage (i,j) indicates that the terminal is in the backoff stage i in the power line channel and in the backoff stage j in the wireless channel. When the terminal enters the backoff stage (i,j), the value of BC is in {0,…,CW i -1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase.

[0025] According to certain embodiments of the second aspect, the terminal uses a carrier sense multiple access / collision avoidance protocol mechanism to monitor the power line channel and check whether the power line channel is idle; the terminal uses a distributed coordination function DCF to monitor the wireless channel and check whether the wireless channel is idle.

[0026] According to some embodiments of the second aspect, the channel monitoring module includes:

[0027] The power line channel monitoring unit is used to monitor the power line status. If the power line channel is idle, the value of the power line backoff counter BC is reduced by 1. If the power line channel is busy, the value of the power line backoff counter BC is frozen, and the value of the delay counter DC is reduced by 1. If DC = 0 and the power line channel is detected to be busy again, the terminal directly retreats to the next stage; if the power line backoff counter BC reaches 0, it enters the waiting state and waits for the value of the wireless backoff counter BC0 to reach 0;

[0028] The wireless channel monitoring unit is used to monitor the status of the wireless channel. If the wireless channel is idle, the value of the wireless backoff counter BC0 is reduced by 1. If the wireless channel is busy, the value of the wireless backoff counter BC0 is frozen until the channel is idle. If BC0 reaches 0, it enters a waiting state until the value of the power line backoff counter BC reaches 0.

[0029] According to some embodiments of the second aspect, simultaneously transmitting the same data packet on a power line channel and a wireless channel includes:

[0030] When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, wait for the specified distributed coordination function interframe interval DIFS. If the power line channel and the wireless channel are always idle during the waiting period, transmit the same data frame on the power line channel and the wireless channel.

[0031] According to certain embodiments of the second aspect, the terminal further includes: a transmission control module, which is used to determine that the transmission of the data frame has failed when no confirmation frame is received on the power line channel and the wireless channel, and to add 1 to the values ​​of the two backoff stage counters BPC and BPC0 respectively, and to reset the power line contention window value and the wireless contention window value, reset the values ​​of the two backoff counters BC and BC0, and re-execute the process of monitoring the power line channel and the wireless channel and resending the data frame. In a third aspect, a computer device is provided, the device comprising one or more processors; a memory; and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and when the programs are executed by the processors, the steps of the power line channel and wireless channel parallel access communication method as described in the first aspect of the present invention are implemented.

[0032] In a fourth aspect, a computer storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method for parallel access of power line channels and wireless channels to communication as described in the first aspect of the present invention are implemented.

[0033] Compared with the prior art, the invention has the following beneficial effects: by adopting a power line channel and a wireless channel parallel access communication method to transmit data on a dual-interface site supporting power line channels and wireless channels, the problem of communication failure caused by electromagnetic interference, physical obstacles, etc. in single channel communication is solved, the reliability and anti-interference ability of communication are improved, the collision probability is reduced, the throughput of the system is improved, and an efficient and reliable converged communication solution is provided to meet the needs of the Internet of Things and smart grids. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of a model of a power line and wireless cooperative communication system provided by an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of a channel contention process of a converged terminal provided in an embodiment of the present invention;

[0036] Figure 3 A schematic diagram showing that the throughput of all systems decreases as the number of sites increases, provided in an embodiment of the present invention;

[0037] Figure 4 A schematic diagram of a situation where the collision probability of a system varies with the number of sites provided in an embodiment of the present invention;

[0038] Figure 5 A schematic diagram of a situation in which the normalized throughput of a system provided by an embodiment of the present invention varies with the number of sites;

[0039] Figure 6 A schematic diagram of a situation in which the transmission delay of a system varies with the number of sites provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings.

[0041] A converged terminal is a device that integrates multiple communication methods or interfaces, allowing the terminal to flexibly select and switch between different communication methods to adapt to various application scenarios and requirements. The parallel access algorithm is a communication mechanism that allows devices to use multiple different channels for data transmission at the same time, thereby improving data transmission efficiency, reducing transmission delays, and enhancing system reliability and anti-interference capabilities.

[0042] The embodiment of the present invention provides a method for parallel access of power line channels and wireless channels based on a converged terminal, which improves the communication efficiency of the system through parallel access of dual interfaces. Figure 1 As shown in Figure 1, the model mainly includes the following components: The central coordinator C is responsible for coordinating the communication of the entire network, so that the hybrid communication mode can cooperate smoothly and ensure the transmission and fluency of data between different communication technologies. Each site (e.g., S1, S2, ..., S N ) are equipped with power line and wireless interfaces, and can perform power line communication and wireless communication at the same time. Figure 1 The solid line represents communication via power lines, using the IEEE 1901 standard. The dashed line represents wireless communication, using the IEEE 802.11 standard in a wireless channel.

[0043] Each site can use both powerline and wireless methods for hybrid communication. This approach utilizes different physical layer technologies and various wireless frequency bands, reducing the impact of single-interface wireless sites on system performance. The dual-interface site design increases the choice of communication paths, improves system reliability, and allows the best communication method to be selected based on the actual environment. It is also easy to expand and upgrade, and can adapt to different network sizes and needs.

[0044] A schematic diagram of a channel contention process of a converged terminal provided by an embodiment of the present invention is as follows Figure 2 As shown. After completing a transmission, it is necessary to wait for a short period of time to continue monitoring before sending the next frame. This period of time is usually called the InterFrame Space (IFS). The two commonly used IFS (Interframe Space) are the Distributed Coordination Function Interframe Space (DIFS) and the Short Interframe Space (SIFS). SIFS (Short Interframe Space) is the shortest interframe space and is used to separate the frames belonging to a conversation. During this period, the station should be able to switch from the sending mode to the receiving mode. The frame types that use SIFS (Short Interframe Space) are: ACK frame (acknowledgement frame), CTS frame (clear to send frame), data frame fragmented from an overlong MAC frame, and all frames that reply to AP (access point) probe request frames and any frames sent by the access point AP (access point) in PCF (point coordination function) mode. DIFS (Distributed Coordination Function Interframe Space) is much longer than the interframe space of SIFS (Short Interframe Space). In DCF (Distributed Coordination Function) mode, DIFS (Distributed Coordination Function Interframe Space) is used to send data frames and management frames.

[0045] The 802.11 standard stipulates that any station that wants to send data during idle time must wait for the time DIFS (Distributed Coordination Function Interframe Space) before sending, ensuring that the confirmation frame ACK can be sent first. The source station monitors the channel. If the channel has been idle during the time interval DIFS (Distributed Coordination Function Interframe Space), the source station can send the data frame DATA. After receiving the data frame, the destination station must perform a CRC (Cyclic Redundancy Check). If the CRC check is error-free, it will switch from the receiving state to the sending state. After the time interval SIFS (Short Interframe Space), it will send the confirmation frame ACK to the source station. From the time the source station sends the data frame DATA to the time it receives the confirmation ACK (confirmation frame) (DATA+SIFS+ACK), no other station must be allowed to send data, so that no collision will occur.

[0046] During the communication between station A and station B, station C and station D also need to transmit data. However, since C and D detect that the channel is busy, they must postpone their access to avoid collision. After waiting for the channel to become idle, the two stations send data at the same time after waiting for the specified DIFS (Distributed Coordination Function Interframe Space) interval, which will inevitably lead to a collision. Therefore, CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance Protocol) stipulates that all stations that postpone access must perform a unified backoff algorithm during the contention period to compete for the channel fairly. The contention period is also called the contention window or contention window (CW). The contention window consists of multiple time slots. For example, the contention window CW=15 means that the window size is 15 time slots. When a station enters the contention period, a backoff time slot number should be randomly generated between 0 and CW (contention window value) and a backoff timer should be set. When multiple stations compete for the channel at the same time, the station whose timer counts down to zero first accesses the medium and sends a data frame. At this time, the channel becomes busy, and the other stations that are still backing off freeze their timers, retain their values, and continue to count down the next time they compete for the channel.

[0047] Basic implementation principle of parallel access algorithm: In this system, all stations use CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance) protocol. A parallel access algorithm for wireless and power line communication is designed.

[0048] The embodiment of the present invention provides a method for concurrently accessing a power line channel and a wireless channel based on a converged terminal, and the processing flow includes the following processing steps:

[0049] Step S1: A fusion terminal that supports both power line channels and wireless channels is used as a site, which is also called a dual-interface site. If a site has a data packet to send, the site initializes the backoff phase counters: the power line backoff phase counter BPC (Backoff Phase Counter), the wireless backoff phase counter BPC0 and the power line delay counter DC (Deferred Counter), and initializes the backoff counters: the power line backoff counter BC (Backoff Counter) and the wireless backoff counter BC0. In the context of the present invention, the wireless channel parameters are indicated by a symbol followed by 0 to distinguish them from the power line channel parameters. In the initialization stage, both BPC and BPC0 are initialized to 0, which is the backoff stage (0,0). After initialization, the dual-interface site starts to compete for the channel from the backoff stage (0,0), and executes steps S2 and S3 in parallel.

[0050] In the context of the present invention, backoff stage (i, j) indicates that the dual-interface station is in backoff stage i in the power line channel and in backoff stage j in the wireless channel. Backoff stage (0, 0) means that the station is in backoff stage 0 in the power line channel and in backoff stage 0 in the wireless channel, that is, at this time, the BPC (power line backoff stage counter) value is 0, and the BPC0 (wireless backoff stage counter) value is 0. The station starts to compete for the channel from backoff stage (0, 0). When entering backoff stage (i, j), the value of BC (power line backoff counter) is in {0,…, CW i -1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 (wireless backoff counter) is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase, and the value of DC (power line delay counter) is DC i (Delay counter value at the i-th backoff stage).

[0051] Taking the data in Table 1 as an example, CW (power line contention window value) = [8 16 32 64] indicates that the maximum power line contention window values ​​in the 0th, 1st, 2nd, and 3rd backoff stages are 8, 16, 32, and 64, respectively. CW0 (wireless contention window value) = [32 64 128256] indicates that the maximum wireless contention window values ​​in the 0th, 1st, 2nd, and 3rd backoff stages are 32, 64, 128, and 256, respectively. DC (power line delay counter) = [0 1 3 15] indicates the delay counter value in the 0th, 1st, 2nd, and 3rd backoff stages.

[0052] Step S2: The station uses the CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance) mechanism under the IEEE 1901 protocol to monitor the power line channel, and checks whether the power line channel is idle in each time slot.

[0053] If the power line channel is idle, BC (power line backoff counter) is reduced by 1 and the channel continues to be monitored.

[0054] If the power line channel is busy, freeze the BC (power line backoff counter) value, and reduce the DC (power line delay counter) value by 1. If DC = 0 and the power line channel is detected to be busy again, the station will directly retreat to the next stage (i+1), reset the BC (power line backoff counter) and DC (power line delay counter) counters, and continue to monitor the power line channel. If BC reaches 0, the station enters the waiting state, waiting for the BC0 (wireless backoff counter) of the wireless channel to reach 0; if the BC (power line backoff counter) and BC0 (wireless backoff counter) values ​​are both 0, execute step S4.

[0055] Step S3: The station uses DCF to monitor the wireless channel under the IEEE 802.11 protocol to check whether the wireless channel is idle. DCF is a working mode based on CSMA / CA (Carrier Sense Multiple Access / Collision Avoidance Protocol).

[0056] If the wireless channel is idle, BC0 (wireless backoff counter) is reduced by 1 and the channel continues to be monitored.

[0057] If the wireless channel is busy, freeze BC0 until the channel is idle. If BC0 reaches 0, the station enters a waiting state, waiting for the BC of the power line channel to reach 0; if the values ​​of BC (power line backoff counter) and BC0 (wireless backoff counter) are both 0, execute step S4. In steps S2 and S3, neither the power line channel nor the wireless channel will transmit data.

[0058] Step S4: Perform dual-channel transmission. If both backoff counters BC and BC0 reach 0, the station waits for a time interval DIFS (distributed coordination function inter-frame space). If the power line channel and the wireless channel are always idle during the station's waiting period, the station uses a diversity scheme (transmitting data on the power line channel and the wireless channel simultaneously) to transmit the same data frame DATA on the two channels simultaneously, and enters step S5.

[0059] After receiving the data frame on the power line channel or the wireless channel, the destination station waits for a short interframe space (SIFS) and then sends an acknowledgment frame ACK to the source station on the power line channel or the wireless channel.

[0060] Step S5: When the station receives an ACK signal on the power line channel or the wireless channel, it indicates that the station has successfully transmitted data on the power line channel or the wireless channel. If data transmission is successful on either the power line channel or the wireless channel, it is determined that the station has successfully sent a data packet and the station has successfully transmitted data. Return to step S1.

[0061] If the station does not receive the confirmation frame ACK on the power line channel and the wireless channel, it is determined that the station fails to transmit the data frame, and the values ​​of BPC and BPC0 are increased, so that the station retreats to the next stage, resets the power line contention window value and the wireless contention window value, resets the values ​​of the two backoff counters BC and BC0, and continues to execute steps S2 and S3. To simplify the calculation, assume that the T of the station's data packet is s (Time slot size for successful transmission) = SIFS (short interframe space) + DIFS (distributed coordination function interframe space) + ACK (acknowledgement frame) + time required to transmit data packets. After sending a data frame, the station sends the data frame within the time interval T. s No other data frames are sent within T c (Time slot size when collision occurs) = DIFS (Distributed Coordination Function Inter-Frame Space) + Maximum data packet transmission time.

[0062] Normalized throughput refers to the ratio of actual output traffic to theoretical maximum output traffic, and its value is usually between 0 and 1. If the normalized throughput is less than 1, it indicates a buffer overflow, which means that some of the arriving cells are discarded or delayed in transmission. Average transmission delay refers to the average time required for data to be transmitted from the sender to the receiver. In this system model, assuming that the successful transmission time slot size and collision time slot size of the two channels are the same, the calculation method of normalized throughput and average transmission delay can be derived:

[0063]

[0064] S represents the normalized throughput, P s represents the transmission probability, P tr represents the probability that at least one station is in the sending state, D p represents the size of the data packet to be transmitted, σ represents the time slot length, T c Represents the time slot size of successful transmission, T s represents the time slot size when a collision occurs, t para Represents the average transmission delay.

[0065] Based on the above theoretical analysis, the algorithm was simulated by MATLAB to analyze the relationship between system throughput, collision probability, transmission delay and the number of stations. In this system, all stations have wireless channels and power line channels, and all stations have the same priority. Unless otherwise specified, the simulation parameter settings are shown in Table 1:

[0066] Table 1 Simulation parameter settings

[0067]

[0068]

[0069] Simulation results: The algorithm was simulated by MATLAB, and the performance of the algorithm such as collision probability, transmission probability, transmission delay and throughput under different input parameters was obtained. Figure 3 As shown in the figure, the throughput of all systems decreases as the number of sites increases. The throughput of the parallel access algorithm is better than that of wireless communication and power line communication at any number of sites. This is because dual-media diversity transmission, that is, using power line communication (PLC) and wireless communication (WLC) for data transmission at the same time, can switch or use another medium for transmission when a problem occurs in one medium transmission by using two transmission media at the same time, which greatly improves the reliability of data transmission, reduces the probability of collision, and improves the throughput of the system. Figure 4 The collision probability of the system is shown as it varies with the number of stations, and is analyzed for different contention window values. Figure 5 The normalized throughput of the system is shown as a function of the number of stations, analyzed for different contention window values. Figure 6 The transmission delay of the system varies with the number of sites, and different contention window values ​​are analyzed. c 、T s The settings of parameters such as control parameters affect the overall performance of the system.

[0070] The simulation results show that by comparing the performance of wireless communication and power line systems, the parallel access algorithm can fully utilize the performance advantages of power line communication and wireless communication to improve the system throughput. The throughput of the parallel access algorithm is better than that of single wireless communication and power line communication at any number of stations. This is because data transmission uses power line communication and wireless communication at the same time in dual-medium diversity transmission. By using two transmission media at the same time, when one transmission medium has problems, the system can switch to another transmission medium or use another transmission medium at the same time, which greatly improves the reliability of data transmission, reduces the probability of collision, and increases the throughput of the system.

[0071] In summary, the embodiments of the present invention make full use of the advantages of power line communication and wireless communication. The fusion communication system can effectively reduce the probability of collision, significantly improve the throughput compared with a single communication mode, and improve the success rate of data transmission through dual-channel parallel transmission. It provides an efficient and reliable dual-media fusion communication solution suitable for the Internet of Things and smart grids.

[0072] Another embodiment of the present invention further provides a converged terminal used as a communication site, the terminal is a dual-interface site, which supports both a power line channel and a wireless channel, including:

[0073] A communication initialization module is used to initialize the power line backoff phase counter BPC and the wireless backoff phase counter BPC0 when the station has a data packet to send, enter the backoff phase, and initialize the value of the power line backoff counter BC according to the power line contention window value, initialize the value of the wireless backoff counter BC0 according to the wireless contention window value, and initialize the power line delay counter DC;

[0074] The channel monitoring module is used to monitor the status of the power line channel and the wireless channel at the same time. If any channel is idle, the corresponding backoff counter is decremented. If the channel is busy, the corresponding backoff counter is frozen, and the backoff stage is adjusted according to the value of the power line delay counter. The monitoring is continued until the backoff counters of the two channels are both 0, and the station enters the ready-to-send state;

[0075] A data transmission module, used for transmitting the same data packet on the power line channel and the wireless channel simultaneously when the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, and confirming that the data packet is successfully transmitted after receiving a confirmation frame returned on either channel;

[0076] The transmission control module is used to determine that the transmission of the data frame has failed when no confirmation frame is received on the power line channel and the wireless channel, increase the values ​​of the two backoff stage counters BPC and BPC0, make the site back off to the next stage, reset the power line contention window value and the wireless contention window value, reset the values ​​of the two backoff counters BC and BC0, re-execute the process of monitoring the power line channel and the wireless channel, and resend the data frame.

[0077] The communication initialization module initializes the value of the power line backoff counter BC according to the power line contention window value, and initializes the value of the wireless backoff counter BC0 according to the wireless contention window value, including:

[0078] The station starts to compete for the channel from the backoff stage (0,0). The backoff stage (i,j) indicates that the dual-interface station is in the backoff stage i in the power line channel and in the backoff stage j in the wireless channel. When the station enters the backoff stage (i,j), the value of BC is in {0,…,CW i-1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase.

[0079] The terminal uses the carrier sense multiple access / collision avoidance protocol mechanism under the IEEE 1901 protocol to monitor the power line channel and check whether the power line channel is idle; the terminal uses the distributed coordination function DCF under the IEEE 802.11 protocol to monitor the wireless channel and check whether the wireless channel is idle.

[0080] The channel monitoring module includes:

[0081] The power line channel monitoring unit is used to monitor the power line status. If the power line channel is idle, the value of the power line backoff counter BC is reduced by 1. If the power line channel is busy, the value of the power line backoff counter BC is frozen, and the value of the delay counter DC is reduced by 1. If DC = 0 and the power line channel is detected to be busy again, the station directly retreats to the next stage; if the power line backoff counter BC reaches 0, the station enters the waiting state and waits for the value of the wireless backoff counter BC0 to reach 0;

[0082] The wireless channel monitoring unit is used to monitor the status of the wireless channel. If the wireless channel is idle, the value of the wireless backoff counter BC0 is reduced by 1. If the wireless channel is busy, the value of the wireless backoff counter BC0 is frozen until the channel is idle. If BC0 reaches 0, the station enters a waiting state until the value of the power line backoff counter BC reaches 0.

[0083] When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, the same data packet is transmitted simultaneously on the power line channel and the wireless channel, including:

[0084] When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, they wait for the specified distributed coordination function interframe interval DIFS. If the power line channel and the wireless channel are always idle during the waiting period, the station transmits the same data frame on the power line channel and the wireless channel simultaneously.

[0085] Another embodiment of the present invention also provides a computer device, which includes one or more processors; a memory; and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and when the programs are executed by the processors, the steps of the power line channel and wireless channel parallel access communication method as described above are implemented.

[0086] Another embodiment of the present invention provides a computer storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the method for parallel access of power line channels and wireless channels are implemented as described above.

[0087] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, devices (systems), computer equipment or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0088] The present invention is described with reference to a flowchart of a method according to an embodiment of the present invention. It should be understood that each process in the flowchart and a combination of processes in the flowchart can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flowchart. Figure 1 A device that specifies functions in a process or multiple processes.

[0089] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A function specified in a process or multiple processes.

[0090] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 The steps of a specified function in a process or multiple processes.

Claims

1. A method for parallel access of power line channel and wireless channel, characterized in that: The following steps are involved: When a station has a data packet to send, it initializes the power line backoff phase counter BPC and the wireless backoff phase counter BPC0, enters the backoff phase, and initializes the value of the power line backoff counter BC according to the power line contention window value, initializes the value of the wireless backoff counter BC0 according to the wireless contention window value, and initializes the power line delay counter DC; Monitor the status of the power line channel and the wireless channel. If any channel is idle, decrement the corresponding backoff counter. If the channel is busy, freeze the corresponding backoff counter and adjust the backoff stage according to the value of the power line delay counter DC. Continue monitoring until the backoff counters of both channels are 0. The same data packet is transmitted on the power line channel and the wireless channel, and after receiving the confirmation frame returned on either channel, the successful transmission of the data packet is confirmed.

2. The method according to claim 1, characterized in that Initializing the value of the power line backoff counter BC according to the power line contention window value, and initializing the value of the wireless backoff counter BC0 according to the wireless contention window value, including: The station starts to compete for the channel from the backoff stage (0,0). The backoff stage (i,j) indicates that the dual-interface station is in the backoff stage i in the power line channel and in the backoff stage j in the wireless channel. When the station enters the backoff stage (i,j), the value of BC is in {0,…,CW i -1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase.

3. The method according to claim 1, characterized in that The site uses the carrier sense multiple access / collision avoidance protocol mechanism to monitor the power line channel and check whether the power line channel is idle; the site uses the distributed coordination function DCF to monitor the wireless channel and check whether the wireless channel is idle.

4. The method according to claim 1, characterized in that Monitor the status of the power line channel and the wireless channel. If any channel is idle, decrement the corresponding backoff counter. If the channel is busy, freeze the corresponding backoff counter and adjust the backoff stage according to the value of the power line delay counter. Continue monitoring until the backoff counters of both channels are 0, including: If the power line channel is idle, the value of the power line backoff counter BC is reduced by 1. If the power line channel is busy, the value of the power line backoff counter BC is frozen, and the value of the delay counter DC is reduced by 1. If DC = 0 and the power line channel is detected to be busy again, the station directly retreats to the next stage; if the power line backoff counter BC reaches 0, the station enters the waiting state and waits for the value of the wireless backoff counter BC0 to reach 0; If the wireless channel is idle, the value of the wireless backoff counter BC0 is reduced by 1. If the wireless channel is busy, the value of the wireless backoff counter BC0 is frozen until the channel is idle. If BC0 reaches 0, the station enters a waiting state until the value of the power line backoff counter BC reaches 0.

5. The method according to claim 1, characterized in that: The same data packet is transmitted simultaneously over the powerline channel and the wireless channel, including: When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, they wait for the specified distributed coordination function interframe interval DIFS. If the power line channel and the wireless channel are always idle during the waiting period, the station transmits the same data frame on the power line channel and the wireless channel simultaneously.

6. The method according to any one of claims 1 to 5, characterized in that Also includes: If no confirmation frame is received on the power line channel and the wireless channel, the transmission of the data frame is judged to have failed, the values ​​of the two backoff stage counters BPC and BPC0 are increased by 1 respectively, and the power line contention window value and the wireless contention window value are reset, the values ​​of the two backoff counters BC and BC0 are reset, and the process of monitoring the power line channel and the wireless channel and resending the data frame is re-executed.

7. A fusion terminal, characterized in that: The terminal comprises: A communication initialization module is used to initialize the power line backoff phase counter BPC and the wireless backoff phase counter BPC0 when the terminal has a data packet to send, enter the backoff phase, and initialize the value of the power line backoff counter BC according to the power line contention window value, initialize the value of the wireless backoff counter BC0 according to the wireless contention window value, and initialize the power line delay counter DC; The channel monitoring module is used to monitor the status of the power line channel and the wireless channel. If any channel is idle, the corresponding backoff counter is decremented. If the channel is busy, the corresponding backoff counter is frozen and the backoff stage is adjusted according to the value of the power line delay counter. The monitoring is continued until the backoff counters of the two channels are both 0. The data sending module is used to transmit the same data packet on the power line channel and the wireless channel when the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, and confirm that the data packet is successfully transmitted after receiving a confirmation frame returned on either channel.

8. The terminal according to claim 7, characterized in that: Initializing the value of the power line backoff counter BC according to the power line contention window value, and initializing the value of the wireless backoff counter BC0 according to the wireless contention window value, including: The terminal starts to compete for the channel from the backoff stage (0,0). The backoff stage (i,j) indicates that it is in the backoff stage i in the power line channel and in the backoff stage j in the wireless channel. When the terminal enters the backoff stage (i,j), the value of BC is in {0,…,CW i -1} randomly selected, CW i is the power line contention window value in the i-th backoff phase, and the value of BC0 is in {0,…,CW0 j -1} randomly selected, CW0 j is the wireless contention window value in the jth backoff phase.

9. The terminal according to claim 7, characterized in that: The terminal uses the carrier sense multiple access / collision avoidance protocol mechanism to monitor the power line channel and check whether the power line channel is idle; the terminal uses the distributed coordination function DCF to monitor the wireless channel and check whether the wireless channel is idle.

10. The terminal according to claim 7, characterized in that: The channel monitoring module includes: The power line channel monitoring unit is used to monitor the power line status. If the power line channel is idle, the value of the power line backoff counter BC is reduced by 1. If the power line channel is busy, the value of the power line backoff counter BC is frozen, and the value of the delay counter DC is reduced by 1. If DC = 0 and the power line channel is detected to be busy again, the station directly retreats to the next stage; if the power line backoff counter BC reaches 0, it enters the waiting state and waits for the value of the wireless backoff counter BC0 to reach 0; The wireless channel monitoring unit is used to monitor the status of the wireless channel. If the wireless channel is idle, the value of the wireless backoff counter BC0 is reduced by 1. If the wireless channel is busy, the value of the wireless backoff counter BC0 is frozen until the channel is idle. If BC0 reaches 0, it enters a waiting state until the value of the power line backoff counter BC reaches 0.

11. The terminal according to claim 7, characterized in that: The same data packet is transmitted simultaneously over the powerline channel and the wireless channel, including: When the values ​​of the power line backoff counter BC and the wireless backoff counter BC0 both reach 0, the terminal waits for the specified distributed coordination function interframe interval DIFS. If the power line channel and the wireless channel are always idle during the waiting period, the terminal transmits the same data frame on the power line channel and the wireless channel.

12. The terminal according to any one of claims 7 to 11, characterized in that: Also includes: The transmission control module is used to determine that the transmission of the data frame has failed when no confirmation frame is received on the power line channel and the wireless channel, increase the values ​​of the two backoff stage counters BPC and BPC0 by 1 respectively, reset the power line contention window value and the wireless contention window value, reset the values ​​of the two backoff counters BC and BC0, re-execute the process of monitoring the power line channel and the wireless channel, and resend the data frame.

13. A computer device, characterized in that: The device includes one or more processors; a memory; and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and when the programs are executed by the processors, the steps of the power line channel and wireless channel parallel access communication method as described in any one of claims 1-6 are implemented.

14. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power line channel and wireless channel parallel access communication method according to any one of claims 1 to 6 are implemented.

Images