Multi-carrier communication system dynamic bit allocation method, medium and terminal

Abstract

The invention is suitable for the technical field of Internet of Things communication, and relates to a multi-carrier communication system dynamic bit allocation method, a medium and a terminal, and the method comprises the following steps: S10, a network node periodically broadcasts and sends a channel evaluation message, and monitors channel evaluation messages sent by other surrounding nodes; s20, the network node updates own channel state information in real time according to the collected channel evaluation messages sent by other nodes; s30, when the network node needs to send data, calculating a bit allocation initial value according to channel state information of the network node; and S40, the network node compares the difference between the sending data volume and the bit allocation initial value, and dynamically adjusts the bit allocation value until the sending requirement is met. According to the invention, the bit allocation value is dynamically adjusted in real time according to the channel state information of the network nodes, the spectrum efficiency and energy efficiency of a communication system are improved through intelligent resource allocation, high quality of data transmission and high utilization rate of spectrum resources are ensured, the complexity is low, and the robustness is strong.

Description

Technical Field

[0001] The present invention belongs to the technical field of Internet of Things communication, and particularly relates to a dynamic bit allocation method, medium and terminal for a multi-carrier communication system. Background Art

[0002] With the rapid evolution of the new power system, the low-voltage power Internet of Things, as the core network connecting terminal devices such as smart meters, distributed energy sources, and electric vehicle charging piles, urgently needs efficient and reliable communication technology support. Multi-carrier communication technology has become a key technology for low-voltage power Internet of Things communication systems due to its high spectral efficiency, ability to resist multipath fading and narrowband interference. However, the low-voltage power line channel has characteristics such as strong time-variation, high noise interference (such as impulse noise, periodic narrowband noise), and load volatility. Traditional static resource allocation schemes cannot dynamically adjust according to the real-time channel state of subcarriers, resulting in waste or overload of spectral resources of some subcarriers; and when the channel undergoes deep fading or sudden noise interference, the bit error rate is prone to surge, making it difficult to meet the requirements of high-reliability services such as real-time monitoring and demand response in the smart grid.

[0003] Dynamic bit allocation can significantly improve system capacity, energy efficiency, and robustness by dynamically adjusting the bit distribution of each subcarrier through real-time sensing of channel state information. Designing an efficient and low-complexity dynamic bit allocation algorithm for low-voltage power Internet of Things scenarios has become a research hotspot in the current power communication field. The patent with the publication number CN101695062B provides a method based on the Hughes-Hartogs algorithm, which selects the optimal subcarrier to allocate bits through grouped iteration, and has the advantage of low transmission power, but the allocation method is prone to falling into local optimum and lacks flexibility; the patent with the publication number CN108494717B provides a method of splitting serial data to be sent into active subcarriers and allocating bits to subcarriers according to the characteristics of the sea surface short-wave ground wave channel, which can obtain better bit error performance, but the convergence speed and stability still need to be improved.

[0004] Therefore, how to provide a dynamic bit allocation method with low complexity, high spectral resource utilization rate, and strong robustness is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a dynamic bit allocation method for a multi-carrier communication system to solve the problems of high complexity, low spectral resource utilization rate, and poor robustness in dynamic bit allocation in the prior art; in addition, the present invention also provides a medium and a terminal for dynamic bit allocation of a carrier communication system.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for dynamic bit allocation in a multi-carrier communication system, including the following steps:

[0008] S10. The network node periodically broadcasts and sends a channel evaluation message, and listens for channel evaluation messages sent by other surrounding nodes;

[0009] S20. The network node updates its own channel state information in real time according to the channel evaluation messages sent by other nodes collected;

[0010] S30. When the network node needs to send data, calculate the initial value of bit allocation according to its own channel state information;

[0011] S40. The network node compares the difference between the data volume to be sent and the initial value of bit allocation, and dynamically adjusts the bit allocation value until the sending requirement is met.

[0012] Further, in step S20, when the network node receives a channel evaluation message sent by another node in the network, it updates the channel state information CSI according to the following formula n :

[0013]

[0014] where N represents the number of subcarriers in the multi-carrier communication system; n represents the subcarrier number in the multi-carrier communication system, and the value range is [1, N]; CSI n represents the channel state information of the subcarrier numbered n; represents the total energy of the subcarrier numbered n calculated in the received channel evaluation message; represents the signal energy of the subcarrier numbered n known in the channel evaluation message.

[0015] Further, the specific steps of step S30 are as follows:

[0016] S301. The network node calculates the average CSI according to the channel state information counted in step S20 by using the following formula mean :

[0017]

[0018] where N represents the number of subcarriers in the multi-carrier communication system; n represents the subcarrier number in the multi-carrier communication system; CSI n represents the channel state information of the subcarrier numbered n;

[0019] S302. The network node calculates the channel state threshold CSI corresponding to the bit allocation according to the following formula thr :

[0020]

[0021] Among them, represents the lower boundary of the channel state threshold; represents the upper boundary of the channel state threshold; CSI min represents the minimum value of the channel state information of each subcarrier, CSI max represents the maximum value of the channel state information of each subcarrier;

[0022] S303. The network node performs initial bit allocation for each subcarrier according to the channel state threshold determined in the step S302 and the channel state information of each subcarrier according to the following formula:

[0023]

[0024] where R n represents the initial number of bits allocated to the subcarrier numbered n.

[0025] Furthermore, in the step S40, the bit allocation value is dynamically adjusted according to the following formula:

[0026] S401. The network node calculates the initial total allocated number of bits R total :

[0027]

[0028] S402. The network node adjusts the initial bit allocation according to the total number of bits R target to be transmitted and the initial total allocated number of bits R total according to the following method:

[0029] If R total > R target , then find the subcarrier with the minimum CSI n and R n > 0, and adjust R n = R n -1, so that R total = R total -1;

[0030] If R total < R target , then find the subcarrier with the maximum CSI n and R n < 4 subcarriers, and adjust R n = R n +1, so that R total = R total +1;

[0031] S403. Repeat the step S402 until the bit allocation of the network node satisfies R total = R target , and complete the dynamic bit allocation.

[0032] Further, in the step S10, within a channel evaluation period of [1, 15] seconds, the network node broadcasts at least once a channel evaluation message to the network.

[0033] Further, in the step S10, the channel evaluation message consists of [5, 15] known and repeated data symbols, and the signal energy and modulation mode of each subcarrier within the data symbol are kept consistent.

[0034] In a second aspect, the present invention further provides a computer-readable storage medium, where the storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned method is implemented.

[0035] In a third aspect, the present invention further provides an electronic terminal, including: a processor and a memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the terminal executes the above-mentioned method.

[0036] Compared with the prior art, the dynamic bit allocation method, medium and terminal of the multi-carrier communication system provided by the present invention have at least the following beneficial effects:

[0037] The traditional static resource allocation scheme cannot dynamically adjust according to the real-time channel state of the subcarriers, resulting in waste or overload of the spectrum resources of some subcarriers; and when there is deep channel fading or burst noise interference, the bit error rate is likely to surge, making it difficult to meet the requirements of high-reliability services such as real-time monitoring and demand response in the smart grid. The process of the present invention is simple and the operation is convenient. Through the specially designed mechanism for the network node to collect channel state information, supplemented by the specially designed dynamic adjustment bit allocation process and conditions, the computational complexity of the optimal bit allocation is effectively reduced, the occurrence of network oscillation is avoided, the high quality of data transmission and the high utilization rate of spectrum resources are ensured, and the robustness of the dynamic bit allocation is also improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the solution of the present invention, the following will briefly introduce the drawings required in the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0039] Figure 1 is a flowchart of a dynamic bit allocation method for a multi-carrier communication system provided by an embodiment of the present invention;

[0040] Figure 2 A comparison graph of the number of bits transmitted per symbol between a dynamic bit allocation method for a multi - carrier communication system provided by an embodiment of the present invention and other algorithms in a simulation environment;

[0041] Figure 3 A comparison graph of the total running time between a dynamic bit allocation method for a multi - carrier communication system provided by an embodiment of the present invention and other algorithms in a simulation environment. Detailed implementation manners

[0042] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0044] The present invention provides a dynamic bit allocation method for a multi - carrier communication system, which is applied to the optimal bit allocation problem of a low - voltage power Internet of Things multi - carrier communication system. The dynamic bit allocation method for the multi - carrier communication system includes the following steps:

[0045] S10. The network node periodically broadcasts and sends channel evaluation messages and listens for channel evaluation messages sent by other surrounding nodes; S20. The network node updates its own channel state information in real - time according to the channel evaluation messages sent by other nodes collected; S30. When the network node needs to send data, it calculates the initial value of bit allocation according to its own channel state information; S40. The network node compares the difference between the amount of data to be sent and the initial value of bit allocation, and dynamically adjusts the bit allocation value until the sending requirement is met.

[0046] According to the channel state information of the network node, the present invention dynamically adjusts the bit allocation value in real - time. Through intelligent resource allocation, the spectrum efficiency and energy efficiency of the communication system are improved, the high quality of data transmission and the high utilization rate of spectrum resources are ensured, and it has low complexity and strong robustness.

[0047] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings.

[0048] The present invention provides a dynamic bit allocation method for a multi-carrier communication system, which is applied to the optimal bit allocation problem of a multi-carrier communication system in a low-voltage power Internet of Things, and combines Figures 1 to 3 In this embodiment, the dynamic bit allocation method for the multi-carrier communication system includes the following steps:

[0049] S10. The network node periodically broadcasts and sends a channel evaluation message, and listens for channel evaluation messages sent by other surrounding nodes.

[0050] Specifically, in this embodiment, within a channel evaluation period of [1, 15] seconds, the network node broadcasts and sends at least 1 channel evaluation message to the network. The channel evaluation message consists of [5, 15] known and repeated data symbols, and the signal energy of each subcarrier within the data symbol is consistent with the modulation method.

[0051] S20. The network node updates its own channel state information in real time according to the channel evaluation messages sent by other nodes collected.

[0052] Specifically, in this embodiment, when the network node receives a channel evaluation message sent by other nodes in the network, it updates the channel state information CSI according to the following formula n :

[0053]

[0054] where N represents the number of subcarriers in the multi-carrier communication system; n represents the subcarrier number in the multi-carrier communication system, and the value range is [1, N]; CSI n represents the channel state information of the subcarrier numbered n; represents the total energy of the subcarrier numbered n calculated in the received channel evaluation message; represents the signal energy of the subcarrier numbered n known in the channel evaluation message.

[0055] Specifically, in this embodiment, for example, when the network node receives a channel evaluation message currently sent by other nodes, and calculates that the total energy of the subcarrier numbered n in the message is 101 mW, and the signal energy is 90 mW, then it can be calculated as follows:

[0056]

[0057] S30. When the network node needs to send data, it calculates the initial value of bit allocation according to its own channel state information.

[0058] Specifically, in this embodiment, step S30 is processed using the following process:

[0059] S301. The network node calculates the average CSI according to the channel state information statistically obtained in step S20 using the following formula mean :

[0060]

[0061] where N represents the number of subcarriers in the multi-carrier communication system; n represents the subcarrier number in the multi-carrier communication system; CSI n represents the channel state information of the subcarrier numbered n.

[0062] In this embodiment, for example, the multi-carrier communication system has 4 subcarriers, and their CSIs are {4.26, 7.84, 9.13, 11.67}, then CSI mean is calculated as follows:

[0063]

[0064] S302. The network node calculates the channel state threshold CSI corresponding to the bit allocation according to the following formula thr :

[0065]

[0066] where represents the lower boundary of the channel state threshold; represents the upper boundary of the channel state threshold; CSI min represents the minimum value of the channel state information of each subcarrier, and CSI max represents the maximum value of the channel state information of each subcarrier.

[0067] Specifically, in this embodiment, for example, in the multi-carrier communication system of step S301, its and are calculated as follows respectively:

[0068]

[0069] S303. The network node performs initial bit allocation for each subcarrier according to the channel state threshold determined in step S302 and the channel state information of each subcarrier using the following formula:

[0070]

[0071] where R n represents the initial number of bits allocated to the subcarrier numbered n.

[0072] Specifically, in this embodiment, for example, in the multi-carrier communication system of step S302, and are calculated as follows respectively:

[0073]

[0074] S40. The network node compares the difference between the transmitted data volume and the initial value of bit allocation, and dynamically adjusts the bit allocation value until the transmission requirement is met.

[0075] Specifically, in this embodiment, the specific process of step S40 is as follows:

[0076] S401. The network node calculates the initial total allocated number of bits R according to the initial values of subcarrier bit allocation calculated in step S303 total :

[0077]

[0078] Specifically, in this embodiment, for example, for the multi-carrier communication system and its initial values of bit allocation in step S303, calculate R total as follows:

[0079] R total = 1 + 2 + 3 + 4 = 10.

[0080] S402. The network node adjusts the initial bit allocation according to the total number of bits R to be transmitted target and the initial total allocated number of bits R total as follows:

[0081] If R total > R target , then find the subcarrier with the smallest CSI n and R n > 0, and adjust R n = R n - 1, so that R total = R total - 1;

[0082] If R total < R target , then find the subcarrier with the largest CSI n and R n < 4 subcarriers, and adjust R n = R n + 1, so that R total = R total + 1.

[0083] Specifically, in this embodiment, for example, for the multi-carrier communication system and its initial values of bit allocation in step S303, if the total number of bits R to be transmitted target = 9, then adjust the 1st subcarrier with the smallest CSI and allocated 1 bit of information, so that the number of allocated subcarriers is reduced by 1. After completion, the total allocated number of bits R total= 9. If the total number of bits to be transmitted is R target = 11, then the sub - carrier No. 4 with the largest CSI and allocated 4 - bit information is adjusted to increase the number of allocated sub - carriers by 1. After completion, the total number of allocated bits R total = 11.

[0084] S403. Repeat step S402 until the bit allocation of the network node satisfies R total = R target , and the dynamic bit allocation is completed.

[0085] Specifically, in this embodiment, for example, the multi - carrier communication system and its initial bit allocation in step S303, after the dynamic allocation process in step S402, it has satisfied R total = R target , then the dynamic bit allocation ends.

[0086] Furthermore, in order to reflect the practicability and effectiveness of the dynamic bit allocation method for the multi - carrier communication system provided in the embodiments of the present invention, engineers built a test and simulation platform for dynamic bit allocation of the multi - carrier communication system in the low - voltage power Internet of Things. The test and simulation platform uses 512 sub - carriers, and the channel model is a standard AWGN (additive white Gaussian noise) channel. During the simulation process, the signal transmission power is kept constant, and the performance of the dynamic bit allocation method in different communication environments is tested by continuously increasing the channel white noise power. The test results are as shown in Figure 2 and Figure 3 . The above - mentioned test results show that the method of the present invention effectively reduces the computational complexity of the optimal bit allocation, avoids the occurrence of network oscillations, and ensures the high quality of data transmission and the high utilization rate of spectrum resources.

[0087] The embodiments of the present invention also provide a computer - readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements any one of the methods in this embodiment.

[0088] The embodiments of the present invention also provide an electronic terminal, including: a processor and a memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the terminal executes any one of the methods in this embodiment.

[0089] For the computer - readable storage medium in this embodiment, those of ordinary skill in the art can understand that all or part of the steps to implement the above - mentioned method embodiments can be completed by hardware related to the computer program. The foregoing computer program can be stored in a computer - readable storage medium. When the program is executed, it executes the steps including the above - mentioned method embodiments; and the foregoing storage medium includes: various media such as ROM, RAM, magnetic disk, or optical disk that can store program codes.

[0090] The electronic terminal provided in this embodiment includes a processor, a memory, a transceiver, and a communication interface. The memory and the communication interface are connected to the processor and the transceiver to complete communication therebetween. The memory is used to store computer programs, the communication interface is used for communication, and the processor and the transceiver are used to run the computer programs to enable the electronic terminal to execute each step of the above method.

[0091] Compared with the prior art, for the multi-carrier communication system dynamic bit allocation method, medium, and terminal described in the above embodiments, the traditional static resource allocation scheme cannot dynamically adjust according to the real-time channel state of sub-carriers, resulting in waste or overload of spectrum resources of some sub-carriers; and when there is deep channel fading or burst noise interference, the bit error rate is likely to surge, making it difficult to meet the requirements of high-reliability services such as real-time monitoring and demand response in smart grids. The process of the present invention is simple and convenient to operate. Through a specially designed mechanism for the network node to collect channel state information, supplemented by a specially designed dynamic adjustment bit allocation process and conditions, the computational complexity of the optimal bit allocation is effectively reduced, the occurrence of network oscillation is avoided, the high quality of data transmission and the high utilization rate of spectrum resources are ensured, and the robustness of the dynamic bit allocation is also improved.

[0092] Obviously, the embodiments described above are only the preferred embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are given in the drawings, but the patent scope of the present invention is not limited. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing specific embodiments, or perform equivalent replacement on some of the technical features. Any equivalent structure directly or indirectly using the content of the specification and drawings of the present invention in other related technical fields shall be similarly within the scope of the patent protection of the present invention.

Claims

1. A dynamic bit allocation method for a multi-carrier communication system, characterized in that: The following steps are involved: S10, the network node periodically broadcasts and sends a channel assessment message, and monitors the channel assessment messages sent by other surrounding nodes; S20, the network node updates its own channel state information in real time according to the collected channel assessment messages sent by other nodes; S30, when the network node needs to send data, it calculates the initial value of bit allocation according to its own channel state information; S40: The network node compares the difference between the amount of transmitted data and the initial value of bit allocation, and dynamically adjusts the bit allocation value until the transmission requirement is met.

2. A method for dynamic bit allocation in a multi-carrier communication system according to claim 1, characterized in that: In step S20, the network node receives a channel assessment message sent by other nodes in the network and updates the channel state information CSI according to the following formula: n : Where N represents the number of subcarriers in the multicarrier communication system; n represents the subcarrier number in the multicarrier communication system, and its value range is [1, N]; CSI n Indicates the channel status information of the subcarrier numbered n; Indicates the total energy of the subcarrier numbered n calculated in the received channel assessment message; Indicates the signal energy of the subcarrier with a known number of n in the channel assessment message.

3. A method for dynamic bit allocation in a multi-carrier communication system according to claim 2, characterized in that: The specific steps of step S30 are as follows: S301: The network node calculates the average CSI according to the channel state information counted in step S20 using the following formula: mean : Where N represents the number of subcarriers in the multicarrier communication system; n represents the subcarrier number in the multicarrier communication system; CSI n Indicates the channel status information of the subcarrier numbered n; S302: The network node calculates the channel state threshold CSI corresponding to the bit allocation according to the following formula: thr : in, Indicates the lower boundary of the channel state threshold; Indicates the upper limit of the channel status threshold; CSI min Indicates the minimum value of the channel state information of each subcarrier, CSI max Indicates the maximum value of the channel state information of each subcarrier; S303: The network node performs initial bit allocation for each subcarrier according to the channel state threshold determined in step S302 and the channel state information of each subcarrier according to the following formula: Among them, R n Indicates the initial number of bits allocated to the subcarrier numbered n.

4. A method for dynamic bit allocation in a multi-carrier communication system according to claim 3, characterized in that: In step S40, the bit allocation value is dynamically adjusted according to the following formula: S401: The network node calculates the initial total number of allocated bits R according to the initial value of bit allocation of each subcarrier calculated in step S303. total : S402: The network node sends a total number of bits R target The total number of allocated bits R total , adjust the initial bit allocation as follows: If R total >R target , then find CSI n Minimum and R n >0 subcarrier, adjust R n =R n -1, making R total =R total -1; If R total <R target , then find CSI n Maximum and R n <4 subcarriers, adjust R n =R n +1, making R total =R total +1; S403, repeat step S402 until the bit allocation of the network node satisfies R total =R target , completing dynamic bit allocation.

5. A method for dynamic bit allocation in a multi-carrier communication system according to claim 1, characterized in that: In the step S10, within a channel assessment cycle of [1,15] seconds, the network node broadcasts a channel assessment message to the network at least once.

6. A method for dynamic bit allocation in a multi-carrier communication system according to claim 1, characterized in that: In step S10, the channel assessment message is composed of [5, 15] known and repeated data symbols, and the signal energy of each subcarrier in the data symbol is consistent with the modulation mode.

7. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

8. An electronic terminal, characterized in that: include: Processor and memory; The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the terminal executes the method according to any one of claims 1 to 6.

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