阅读说明：本技术 一种拥塞控制方法及车载终端 (Congestion control method and vehicle-mounted terminal ) 是由 许珺 周晶 严斌峰 栾帅 丁志东 于 2021-07-05 设计创作，主要内容包括：本发明提供一种拥塞控制方法及车载终端,所述方法包括：获取车联网直连通信频段上各子信道的使用情况；根据所述使用情况判断是否存在信道拥塞；若存在,则降低自身发射功率,并向车联网中的其他车载终端发送群体功率控制消息,以使所述其他车载终端接收到所述群体功率控制消息后降低各自的发射功率。该方法及车载终端能够解决相关技术中当区域内聚集大量车载终端时,未获得无线资源的车载终端因存在始终找不到满足自己发送基本安全信息所需的无线资源块,从而容易导致交通安全的问题。(The invention provides a congestion control method and a vehicle-mounted terminal, wherein the method comprises the following steps: acquiring the use condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles; judging whether channel congestion exists according to the using condition; if the group power control message exists, the transmitting power of the vehicle-mounted terminal is reduced, and the group power control message is sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals reduce the respective transmitting power after receiving the group power control message. The method and the vehicle-mounted terminal can solve the problem that traffic safety is easily caused because the vehicle-mounted terminal which does not obtain wireless resources can not always find the wireless resource block which meets the requirement of sending basic safety information by the vehicle-mounted terminal when a large number of vehicle-mounted terminals are gathered in an area in the related technology.)

1. A congestion control method applied to a first vehicle-mounted terminal, the method comprising:

acquiring the use condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles;

judging whether channel congestion exists according to the using condition;

if the group power control message exists, the transmitting power of the vehicle-mounted terminal is reduced, and the group power control message is sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals reduce the respective transmitting power after receiving the group power control message.

2. The congestion control method according to claim 1, wherein the obtaining of the use condition of each sub-channel on the direct communication frequency band in the internet of vehicles specifically comprises:

in a preset measurement period, the receiving power of each sub-channel on the direct connection communication frequency band of the Internet of vehicles is continuously measured to obtain the service condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles.

3. The congestion control method according to claim 1, wherein the determining whether there is channel congestion according to the usage condition specifically includes:

calculating a channel busy rate CBR according to the use condition;

judging whether the CBR is larger than a preset first threshold value or not;

if so, judging that channel congestion exists, otherwise, judging that the channel congestion does not exist.

4. The congestion control method according to claim 3, wherein the calculating a channel busy rate CBR according to the usage situation specifically includes:

acquiring the number of used sub-channels in a preset measurement period, wherein the used sub-channels are sub-channels with receiving power exceeding a preset second threshold;

acquiring the total number of all sub-channels in the preset measurement period;

and calculating the CBR, wherein the CBR is the ratio of the number of the used sub-channels in the preset measurement period to the total number of all the sub-channels in the preset measurement period.

5. The congestion control method according to claim 4, wherein the predetermined measurement period is a predetermined time period or a plurality of consecutive radio frames.

6. The congestion control method according to claim 1, wherein the reducing the self-transmission power specifically comprises:

and reducing the self-transmitting power by a preset proportion or a preset numerical value.

7. The congestion control method according to claim 1, wherein the method further comprises:

and if the channel congestion does not exist, increasing the self transmitting power by a preset proportion or a preset numerical value.

8. A vehicle-mounted terminal characterized by comprising:

the wireless resource sensing module is used for acquiring the use condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles;

the channel congestion judging module is connected with the wireless resource sensing module and used for judging whether channel congestion exists according to the use condition;

and the power control module is connected with the channel congestion judgment module and used for reducing the self transmitting power and sending group power control messages to other vehicle-mounted terminals in the vehicle network when the judgment result of the channel congestion judgment module is that the self transmitting power exists, so that the other vehicle-mounted terminals reduce the respective transmitting power after receiving the group power control messages.

9. The vehicle-mounted terminal according to claim 8, wherein the radio resource sensing module is specifically configured to continuously measure received power of each sub-channel in the direct-connected communication frequency band of the internet of vehicles in a preset measurement period, so as to obtain a use condition of each sub-channel in the direct-connected communication frequency band of the internet of vehicles.

10. An in-vehicle terminal comprising a memory and a processor, wherein the memory has stored therein a computer program, and the processor is configured to run the computer program to implement the congestion control method according to any one of claims 1 to 7.

Technical Field

The present invention relates to the field of network technologies, and in particular, to a congestion control method and a vehicle-mounted terminal.

Background

At present, the frequency band of 5905-5925 MHz allocated by no committee of China is totally 20MHz bandwidth used for V2X (Vehicle to electric) direct connection communication, including wireless communication links between Vehicle-mounted terminals and between a Vehicle and roadside equipment, and bandwidth resources are limited. Under the condition of no coverage of an operator base station, the wireless resource allocation of V2X direct communication is based on a "perception + reservation" mode, and each terminal estimates its available time-frequency resource blocks according to its perceived wireless resource usage, however, when a large number of vehicle-mounted terminals are gathered in a local area, the following problems may exist: the terminal always senses the use condition of the wireless resources, but cannot always find the wireless resource block required by the terminal to send information. According to the standard, each vehicle-mounted terminal periodically transmits basic safety messages including positions, speeds, accelerations, directions and the like for surrounding vehicles to receive and use for vehicle control, path planning, cooperative lane merging and the like, and if the messages of the vehicles cannot be transmitted to the outside, potential threats are formed on traffic safety.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a congestion control method and a vehicle-mounted terminal, aiming at the above-mentioned deficiencies of the prior art, so as to solve the problem that traffic safety is easily caused because a vehicle-mounted terminal that does not obtain wireless resources cannot always find a wireless resource block that meets the requirement of sending basic safety information by itself when a large number of vehicle-mounted terminals are aggregated in a region in the related art.

In a first aspect, an embodiment of the present invention provides a congestion control method, which is applied to a first vehicle-mounted terminal, and the method includes:

acquiring the use condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles;

judging whether channel congestion exists according to the using condition;

if the group power control message exists, the transmitting power of the vehicle-mounted terminal is reduced, and the group power control message is sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals reduce the respective transmitting power after receiving the group power control message.

Preferably, the obtaining of the use condition of each sub-channel on the direct communication frequency band of the internet of vehicles specifically includes:

in a preset measurement period, the receiving power of each sub-channel on the direct connection communication frequency band of the Internet of vehicles is continuously measured to obtain the service condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles.

Preferably, the determining whether there is channel congestion according to the usage includes:

calculating a channel busy rate CBR according to the use condition;

judging whether the CBR is larger than a preset first threshold value or not;

if so, judging that channel congestion exists, otherwise, judging that the channel congestion does not exist.

Preferably, the calculating of the channel busy rate CBR according to the usage includes:

acquiring the number of used sub-channels in a preset measurement period, wherein the used sub-channels are sub-channels with receiving power exceeding a preset second threshold;

acquiring the total number of all sub-channels in the preset measurement period;

and calculating the CBR, wherein the CBR is the ratio of the number of the used sub-channels in the preset measurement period to the total number of all the sub-channels in the preset measurement period.

Preferably, the preset measurement period is a preset time period or a plurality of continuous radio frames.

Preferably, the reducing of the self-transmitting power specifically includes:

and reducing the self-transmitting power by a preset proportion or a preset numerical value.

Preferably, the method further comprises:

and if the channel congestion does not exist, increasing the self transmitting power by a preset proportion or a preset numerical value.

In a second aspect, an embodiment of the present invention provides a vehicle-mounted terminal, including:

the wireless resource sensing module is used for acquiring the use condition of each sub-channel on the direct connection communication frequency band of the Internet of vehicles;

the channel congestion judging module is connected with the wireless resource sensing module and used for judging whether channel congestion exists according to the use condition;

and the power control module is connected with the channel congestion judgment module and used for reducing the self transmitting power and sending group power control messages to other vehicle-mounted terminals in the vehicle network when the judgment result of the channel congestion judgment module is that the self transmitting power exists, so that the other vehicle-mounted terminals reduce the respective transmitting power after receiving the group power control messages.

Preferably, the radio resource sensing module is specifically configured to continuously measure the received power of each sub-channel on the direct communication frequency band of the internet of vehicles in a preset measurement period, so as to obtain the use condition of each sub-channel on the direct communication frequency band of the internet of vehicles.

In a third aspect, an embodiment of the present invention provides an in-vehicle terminal, including a memory and a processor, where the memory stores a computer program, and the processor is configured to run the computer program to implement the congestion control method according to the first aspect.

According to the congestion control method and the vehicle-mounted terminal provided by the embodiment of the invention, the use condition of each sub-channel on the direct connection communication frequency band of the internet of vehicles is obtained, whether channel congestion exists is judged according to the use condition, and the self transmitting power is reduced when the channel congestion exists, so that the communication opportunity can be created for the vehicle-mounted terminal which is potential and does not obtain wireless resources, and the traffic safety is prevented from being influenced by the fact that the vehicle-mounted terminal cannot communicate for a long time. Meanwhile, in order to further improve the probability of obtaining wireless resources by a potential vehicle-mounted terminal and accelerate the timeliness of congestion control, group power control messages can be sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals correspondingly reduce respective transmitting power after receiving the group power control messages, and the problem that in the related art, when a large number of vehicle-mounted terminals are gathered in an area, the vehicle-mounted terminals which do not obtain the wireless resources cannot always find wireless resource blocks which meet the requirement of sending basic safety information, and therefore traffic safety is easily caused is solved.

Drawings

FIG. 1: is a flow chart of a congestion control method of embodiment 1 of the present invention;

FIG. 2: is a schematic structural diagram of a vehicle-mounted terminal according to embodiment 2 of the present invention;

FIG. 3: a schematic structural diagram of a vehicle-mounted terminal according to embodiment 3 of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following detailed description will be made with reference to the accompanying drawings.

It is to be understood that the specific embodiments and figures described herein are merely illustrative of the invention and are not limiting of the invention.

It is to be understood that the embodiments and features of the embodiments can be combined with each other without conflict.

It is to be understood that, for the convenience of description, only parts related to the present invention are shown in the drawings of the present invention, and parts not related to the present invention are not shown in the drawings.

It should be understood that each unit and module related in the embodiments of the present invention may correspond to only one physical structure, may also be composed of multiple physical structures, or multiple units and modules may also be integrated into one physical structure.

It will be understood that, without conflict, the functions, steps, etc. noted in the flowchart and block diagrams of the present invention may occur in an order different from that noted in the figures.

It is to be understood that the flowchart and block diagrams of the present invention illustrate the architecture, functionality, and operation of possible implementations of systems, apparatus, devices and methods according to various embodiments of the present invention. Each block in the flowchart or block diagrams may represent a unit, module, segment, code, which comprises executable instructions for implementing the specified function(s). Furthermore, each block or combination of blocks in the block diagrams and flowchart illustrations can be implemented by a hardware-based system that performs the specified functions or by a combination of hardware and computer instructions.

It is to be understood that the units and modules involved in the embodiments of the present invention may be implemented by software, and may also be implemented by hardware, for example, the units and modules may be located in a processor.

Example 1:

as shown in fig. 1, the present embodiment provides a congestion control method applied to a first vehicle-mounted terminal, where the method includes:

step S102: and obtaining the service conditions of all sub-channels on the direct connection communication frequency band of the Internet of vehicles.

In this embodiment, the first vehicle-mounted terminal may be a vehicle-mounted terminal in which any one of the vehicle networks has accessed the sub-channel in a "perception + reservation" manner, and perceives the power usage of the peripheral channel of the vehicle-mounted terminal by obtaining the usage of each sub-channel on the direct connection communication frequency band of the vehicle network, wherein the direct connection communication frequency band of the vehicle network is a frequency band of 5905-5925 MHz, and the direct connection communication frequency band of the vehicle network is divided into a plurality of sub-channels in advance.

In this embodiment, in order to sense and infer the possibility of congestion in time, the first vehicle-mounted terminal continuously measures the received power of each sub-channel on the direct-connected communication frequency band of the internet of vehicles, so as to obtain the use condition of each sub-channel on the direct-connected communication frequency band of the internet of vehicles.

Step S104: and judging whether channel congestion exists according to the use condition.

Specifically, the first vehicle-mounted terminal calculates a channel Busy rate CBR (channel Busy ratio) according to the use condition of each sub-channel, and determines whether the CBR is greater than a preset first threshold, if so, it is determined that channel congestion exists, and otherwise, it is determined that channel congestion does not exist.

In this embodiment, the channel busy rate CBR may be calculated according to the following formula: CBR is the number of subchannels used in the measurement period ÷ the total number of all subchannels in the measurement period. The measurement period may be preset, and may be set to a preset time period T0 or a plurality of consecutive radio frames. The used sub-channels are sub-channels with receiving power exceeding a preset second threshold P0, each vehicle-mounted terminal in the internet of vehicles, which has accessed into the sub-channels in a "sensing + reservation" manner, calculates CBR by itself, and determines whether the current channel is in a congestion state by itself, the first threshold CBR0 preset by each vehicle-mounted terminal, which has accessed into the sub-channels in a "sensing + reservation" manner, may be the same or different, and may be specifically set according to an actual situation, for example, a priority may be set in advance for each vehicle-mounted terminal according to the actual situation, the first threshold set with a high priority may be relatively high, and finally, the calculated CBR is compared with the first threshold CBR0, if the CBR is not greater than CBR0, it is determined that the vehicle-mounted terminal is not congested, and if the CBR is greater than CBR0, it is determined that the vehicle-mounted terminal is congested.

Step S106: if the group power control message exists, the self transmitting power is reduced, and the group power control message is sent to other vehicle terminals in the Internet of vehicles, so that the other vehicle terminals reduce the respective transmitting power after receiving the group power control message.

In this embodiment, when the first vehicle-mounted terminal determines that the channel is congested, in order to create a communication opportunity for a potential vehicle-mounted terminal that does not obtain a wireless resource and avoid that the vehicle-mounted terminal affects traffic safety due to long-term inability to communicate, the self-transmitting power may be reduced by reducing the self-transmitting power by a preset ratio or a preset value. For example, according to the percentage of the maximum transmission power, if the channel congestion is first determined to be reduced to 60%, the continuous congestion is reduced to 30%, and the like until the channel is turned off, thereby yielding the channel of the user, or according to a fixed step size, the channel congestion is gradually reduced, if the channel congestion is first determined to be reduced by 3dB, the continuous congestion is reduced by 3dB again, and the like until the channel is turned off, thereby yielding the channel of the user. It should be noted that, in practical applications, the power reduction method includes, but is not limited to, the above methods.

It should be noted that, in some extreme cases, in order to ensure that the potential in-vehicle terminal obtains the channel, the first in-vehicle terminal may also choose to turn off its transmit power, thereby yielding the channel. For example, when it is determined that the channel is very congested, some vehicle-mounted terminals with low priority may choose to turn off their own transmission power, thereby yielding the channel for the vehicle-mounted terminals with high potential priority.

In this embodiment, in order to further improve the probability of obtaining wireless resources by a potential vehicle-mounted terminal and speed up the timeliness of congestion control, the first vehicle-mounted terminal may send a group power control message to other vehicle-mounted terminals in the vehicle networking while reducing its own transmission power, so that the other vehicle-mounted terminals also correspondingly reduce their respective transmission powers after receiving the group power control message, that is, reduce their own transmission powers by a preset ratio or a preset value. It should be noted that, in the same area, different vehicle-mounted terminals may have different determination results for determining congestion, if one part of the vehicle-mounted terminals may determine a congestion state, and another part of the vehicle-mounted terminals may determine a non-congestion state, as long as any vehicle-mounted terminal in a certain area determines congestion, a group power control message may be broadcast, so that the surrounding vehicle-mounted terminals appropriately reduce their own transmission power according to their own conditions, or release the opportunity to access a sub-channel, thereby ensuring the timeliness and success rate of autonomous congestion control under rapidly changing road conditions, and further improving the probability of obtaining wireless resources by potential vehicle-mounted terminals.

In this embodiment, after each vehicle-mounted terminal in the internet of vehicles properly reduces its own transmission power, a potential vehicle-mounted terminal that does not access the wireless channel may access the sub-channel in a "sensing + reservation" manner, and send a basic security message including its own position, speed, acceleration, direction, and the like, thereby avoiding the problem of affecting traffic safety due to long-term inability to communicate. Meanwhile, when the vehicle-mounted terminal with the reduced transmitting power judges that the channel is not congested any more in the following process, the transmitting power of the vehicle-mounted terminal can be restored to 100%, or the current transmitting power of the vehicle-mounted terminal is maintained, or the transmitting power of the vehicle-mounted terminal is gradually increased by a preset proportion or a preset numerical value until the transmitting power of the vehicle-mounted terminal is restored to 100%.

According to the congestion control method provided by the embodiment, the use condition of each sub-channel on the direct connection communication frequency band of the internet of vehicles is obtained, whether channel congestion exists is judged according to the use condition, and the transmitting power of the congestion control method is reduced when the channel congestion exists, so that a communication opportunity can be created for a potential vehicle-mounted terminal which does not obtain wireless resources, and the traffic safety is prevented from being influenced by the fact that the vehicle-mounted terminal cannot communicate for a long time. Meanwhile, in order to further improve the probability of obtaining wireless resources by a potential vehicle-mounted terminal and accelerate the timeliness of congestion control, group power control messages can be sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals correspondingly reduce respective transmitting power after receiving the group power control messages, and the problem that in the related art, when a large number of vehicle-mounted terminals are gathered in an area, the vehicle-mounted terminals which do not obtain the wireless resources cannot always find wireless resource blocks which meet the requirement of sending basic safety information, and therefore traffic safety is easily caused is solved.

Example 2:

as shown in fig. 2, the present embodiment provides a vehicle terminal including:

the wireless resource sensing module 12 is used for acquiring the use condition of each sub-channel on the direct connection communication frequency band of the internet of vehicles;

the channel congestion judging module 14 is connected with the wireless resource sensing module 12 and used for judging whether channel congestion exists according to the use condition;

and the power control module 16 is connected with the channel congestion decision module 14, and is configured to reduce the own transmit power and send a group power control message to other vehicle-mounted terminals in the vehicle networking when the channel congestion decision module 14 determines that the group power control message exists, so that the other vehicle-mounted terminals reduce their transmit powers after receiving the group power control message.

Optionally, the radio resource sensing module 12 is specifically configured to continuously measure the received power of each sub-channel on the direct communication frequency band of the internet of vehicles in a preset measurement period, so as to obtain the use condition of each sub-channel on the direct communication frequency band of the internet of vehicles.

Optionally, the channel congestion determining module 14 may specifically include:

the CBR calculating unit is used for calculating a channel busy rate CBR according to the use condition;

and the CBR judging unit is used for judging whether the CBR is larger than a preset first threshold value or not, if so, judging that channel congestion exists, and otherwise, judging that the channel congestion does not exist.

Optionally, the CBR calculating unit specifically includes:

a first obtaining unit, configured to obtain the number of used sub-channels in a preset measurement period, where the used sub-channels are sub-channels whose received power exceeds a preset second threshold;

the second acquisition unit is used for acquiring the total number of all sub-channels in a preset measurement period;

and a CBR calculating unit, configured to calculate a CBR, where the CBR is a ratio of the number of used sub-channels in a preset measurement period to the total number of all sub-channels in the preset measurement period.

Optionally, the preset measurement period is a preset time period or a plurality of consecutive radio frames.

Optionally, the power control module 16 is specifically configured to, when the channel congestion decision module 14 determines that the group power control message exists, reduce the own transmit power by a preset ratio or a preset numerical value, and send the group power control message to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals reduce their transmit powers after receiving the group power control message.

Optionally, the power control module 16 is further configured to increase the self-transmitting power by a preset ratio or a preset numerical value if it is determined that there is no channel congestion.

Example 3:

as shown in fig. 3, the present embodiment provides a vehicle terminal including a memory 21 and a processor 22, the memory 21 having a computer program stored therein, and the processor 22 being configured to run the computer program to execute the congestion control method in embodiment 1.

The memory 21 is connected to the processor 22, the memory 21 may be a flash memory, a read-only memory or other memories, and the processor 22 may be a central processing unit or a single chip microcomputer.

The vehicle-mounted terminals provided in embodiments 2 to 3 can create a communication opportunity for a potential vehicle-mounted terminal that does not obtain wireless resources by acquiring the use condition of each sub-channel on the direct-connection communication frequency band of the internet of vehicles, determining whether channel congestion exists according to the use condition, and reducing the transmission power of the vehicle-mounted terminal when the channel congestion is determined to exist, thereby preventing the vehicle-mounted terminal from affecting traffic safety due to long-term communication failure. Meanwhile, in order to further improve the probability of obtaining wireless resources by a potential vehicle-mounted terminal and accelerate the timeliness of congestion control, group power control messages can be sent to other vehicle-mounted terminals in the vehicle networking, so that the other vehicle-mounted terminals correspondingly reduce respective transmitting power after receiving the group power control messages, and the problem that in the related art, when a large number of vehicle-mounted terminals are gathered in an area, the vehicle-mounted terminals which do not obtain the wireless resources cannot always find wireless resource blocks which meet the requirement of sending basic safety information, and therefore traffic safety is easily caused is solved.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.