CN111800885A - Channel contention method and equipment for multi-terminal access - Google Patents

Abstract

The invention discloses a channel contention method and equipment for multi-terminal access, wherein the method comprises the steps of receiving a second RTS frame sent by a second terminal if a base station receives a first RTS frame sent by a first terminal and the base station and the first terminal are carrying out ith data transmission; wherein i is a positive integer greater than or equal to 1; if the ith data transmission between the base station and the first terminal is finished, sending a first ACK frame to the second terminal; the first ACK frame is used for representing that the base station distributes a channel to the second terminal; if the base station and the first terminal perform data transmission for the (i + 1) th time, receiving first data sent by the second terminal; the base station is realized in a mode of allocating channels by polling, two terminals are allowed to simultaneously send and receive data in a mode of not interfering with each other, and the network throughput performance of the cell communication system is improved.

Description

A channel contention method and device for multi-terminal access

technical field

The present invention relates to, but is not limited to, the field of communications, and in particular, to a method and device for channel contention for multi-terminal access.

Background technique

In traditional wireless communication, due to the strong self-interference phenomenon of the signal between the transmitter and the receiver, researchers generally believe that the communication stations cannot simultaneously receive and transmit signals on the same frequency band. With the advancement of self-interference cancellation technology, communication stations can simultaneously transmit and receive signals on the same frequency band. At present, co-frequency simultaneous transmission technology is considered to be an effective technology to improve spectral efficiency. However, the related art cannot solve the problem of channel contention that occurs when multiple terminals perform data interaction with the base station through random access.

SUMMARY OF THE INVENTION

In view of this, embodiments of the present invention provide a channel contention method and device for multi-terminal access, which solves the problem of channel contention in the related art when multi-terminals exchange information with a base station through random access.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

A channel contention method for multi-terminal access, the method is applied to a base station, and the method includes:

If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the second RTS frame sent by the second terminal; wherein the i is a positive integer greater than or equal to 1;

If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal; wherein, the first ACK frame is used to indicate that the base station allocates a channel to the second terminal;

If the base station performs the i+1th data transmission with the first terminal, the first data sent by the second terminal is received.

Optionally, the method further includes:

If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the third RTS frame sent by the third terminal;

Correspondingly, if the i-th data transmission between the base station and the first terminal has been completed, sending the first ACK frame to the second terminal includes:

If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal and the third terminal;

Correspondingly, the receiving the first data sent by the second terminal if the base station performs the i+1th data transmission with the first terminal includes:

Obtain the reception time of the second RTS frame and the reception time of the third RTS frame;

If the receiving time of the second RTS frame is earlier than the receiving time of the third RTS frame, sending a first ACK frame to the second terminal;

If the base station performs the i+1th data transmission with the first terminal, the first data sent by the second terminal is received.

Optionally, after receiving the first data sent by the second terminal if the base station and the first terminal perform the i+1th data transmission, the method further includes:

sending a first CTS frame to the third terminal; wherein the first CTS frame is used to represent that the base station allocates a channel to the third terminal;

If the base station performs the i+2th data transmission with the first terminal, the second data sent by the third terminal is received.

Optionally, after receiving the second data sent by the third terminal if the base station and the first terminal perform the i+2th data transmission, the method further includes:

If the base station receives the third RTS frame sent by the target terminal, it sends a second CTS frame to the target terminal; wherein, the second CTS frame is used to indicate that the base station has successfully received the second data; The target terminal includes the second terminal, the third terminal or the fourth terminal, and the fourth terminal is different from the first terminal, the second terminal and the third terminal.

Optionally, the method further includes:

If the base station does not receive the third RTS frame, it sends a second ACK frame to the third terminal, wherein the second ACK frame is used to indicate that the base station has successfully received the second data.

A channel contention method for multi-terminal access, the method is applied to a second terminal, and the method includes:

If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, the second RTS frame is sent to the base station after waiting for the first time period; wherein , the i is a positive integer greater than or equal to 1;

receiving the first ACK frame fed back by the base station for the second RTS frame; wherein, the first ACK frame is used to represent that the base station allocates a channel to the second terminal;

If the base station and the first terminal perform the i+1th data transmission, send the first data to the base station based on the first ACK frame.

Optionally, if the base station and the first terminal perform the i+1th data transmission, sending the first data to the base station based on the first ACK frame, including:

If after receiving the third RTS frame sent by the base station to the first terminal and waiting for a second time period, the base station and the first terminal perform the i+1th data transmission, based on the first ACK frame, and send the first data to the base station.

A channel contention method for multi-terminal access, the method is applied to a third terminal, and the method includes:

If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, after waiting for a third time period, a fourth RTS frame is sent to the base station; wherein , the third duration is greater than the first duration; the i is a positive integer greater than or equal to 1;

receiving the first CTS frame fed back by the base station for the fourth RTS frame; wherein the first CTS frame is used to represent that the base station allocates a channel to the third terminal;

If the base station and the first terminal perform the i+2th data transmission, send second data to the base station based on the first CTS frame.

Optionally, if the base station and the first terminal perform the i+2th data transmission, send second data to the base station based on the first CTS frame, including:

If after receiving the fifth RTS frame sent by the base station to the first terminal and waiting for a fourth time period, the base station and the first terminal perform the i+2th data transmission, based on the first CTS frame, and send the second data to the base station.

Optionally, if after receiving the fifth RTS frame sent by the base station to the first terminal and waiting for a fourth time period, and the base station and the first terminal perform the i+2th data transmission, After sending the second data to the base station based on the first CTS frame, the method further includes:

A second CTS frame is received to indicate that the base station has successfully received the second data; or, a second ACK frame is received to indicate that the base station has successfully received the second data.

In the channel contention method for multi-terminal access provided by the embodiment of the present invention, if the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, the second terminal receives the The second RTS frame sent; wherein, i is a positive integer greater than or equal to 1; if the i-th data transmission between the base station and the first terminal has been completed, the first ACK frame is sent to the second terminal; wherein, the first ACK The frame is used to indicate that the base station allocates the channel to the second terminal; if the base station and the first terminal perform the i+1th data transmission, the first data sent by the second terminal is received; that is, the base station and the first terminal are in the process of During the i-th data transmission, if the base station receives the second RTS frame sent by other terminals such as the second terminal, the base station will send the second terminal to the second terminal after the data transmission between itself and the first terminal is completed. Give the first ACK frame to the second terminal, so that after the second terminal receives the first ACK frame, when the base station and the first terminal perform the i+1th data transmission, send the first ACK frame to be transmitted to the base station through another channel data, and then the base station receives the first data. In this way, the base station uses a polling method for scheduling, which avoids channel contention during random access by multiple terminals, and solves the problem of data interaction between multiple terminals and the base station through random access in the related art. The problem of channel contention occurs when the base station allocates channels by polling, allowing two terminals to transmit and receive data at the same time without interfering with each other, which can fully improve the network throughput performance of the cell-based communication system.

Description of drawings

FIG. 1 is a schematic flowchart of a channel contention method for multi-terminal access provided by the implementation of the present invention;

2 is a schematic flowchart of another channel contention method for multi-terminal access provided by an embodiment of the present invention;

3 is a schematic flowchart of another method for channel contention for multi-terminal access provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a communication scenario for random access of multiple terminals according to an embodiment of the present invention;

FIG. 5 is a control sequence diagram for random access of multiple terminals according to an embodiment of the present invention;

6 is a schematic flowchart of a channel contention method for multi-terminal access provided by another implementation of the present invention;

7 is a schematic flowchart of another channel contention method for multi-terminal access provided by another implementation of the present invention;

FIG. 8 is a schematic structural diagram of a base station provided by an implementation of the present invention;

FIG. 9 is a schematic structural diagram of a second terminal provided by the implementation of the present invention;

FIG. 10 is a schematic structural diagram of a third terminal provided by the implementation of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Here, the background of channel contention is briefly explained. In the related art, in the future wireless network communication, the simultaneous co-frequency transmission technology can greatly improve the spectral efficiency of the system. In traditional wireless communication, due to the strong self-interference phenomenon of the signal between the transmitter and the receiver, researchers generally believe that communication sites (such as base stations, mobile terminals and other equipment) cannot receive and transmit on the same frequency band at the same time. Signal. With the advancement of self-interference cancellation technology, communication stations can apply In-band Full-Duplex (IBFD) to simultaneously transmit and receive signals on the same frequency band. The duplex (Full-Duplex, FD) technology has gradually matured. To realize the application of IBFD between wireless communication multi-sites, it is necessary to improve the Media Access Control (MAC) layer control method and verify that the IBFD transmission is correct. Impact on system throughput performance.

In the related art, a scheme of using the existing wireless local area network MAC control frame for full-duplex transmission is proposed, which includes the detection process of the full-duplex communication capability. send. But this solution cannot solve the problem of multi-site detection and channel contention.

Aiming at the channel contention and other problems, the embodiment of the present invention solves the channel contention problem through the designed channel access and channel contention method for multi-site access, and introduces an interactive control method of random backoff, which is also applicable to wireless half-dual Therefore, the compatibility of wireless full-duplex communication and half-duplex communication is considered. The base station allocates channels by means of polling, so as to improve the utilization rate of the channels.

As the problems on the physical layer are gradually improved, many studies on the full-duplex MAC layer have been carried out one after another. In the related art, an improved MAC layer protocol is proposed, which allows some interfering nodes to make full use of the channel by finding a suitable rate. This protocol ensures that the channel access time can be shared fairly among all nodes, but cannot solve the problem of full-duplex and half-duplex. To solve the compatibility problem between duplexes, the method provided by the embodiment of the present invention can solve the compatibility problem between full duplex and half duplex.

In the related art, a new request-to-send/full-duplex-clear-to-send (RTS/FCTS) mechanism is proposed on the basis of the MAC layer protocol, which can support wireless full-duplex network communication of bidirectional and non-bidirectional links. The method does not involve the control of multi-point access and channel contention resolution, and the channel contention method for multi-terminal access proposed in the embodiment of the present invention realizes the solution of the channel contention problem of multi-point access.

In the related art, a scheme of using the existing wireless local area network MAC control frame for full-duplex transmission is proposed, which includes the detection process of the full-duplex communication capability. send. But this solution cannot solve the problem of multi-site detection and channel contention.

The channel contention method for multi-terminal access provided by the embodiment of the present invention solves the problem of channel contention and conflict during multi-terminal access in cell-based IBFD communication. The conflict of single-terminal access is relatively small, but The conflicts involved in multi-terminal access are more complicated.

Before further describing the embodiments of the present invention in detail, the terms and terms involved in the embodiments of the present invention are described. The terms and terms involved in the embodiments of the present invention are applicable to the following explanations.

1) RTS frame, request to send frame.

2) a CTS frame, used to reply to an RTS frame; in the embodiment of the present invention, the CTS frame may include a first CTS frame and a second CTS frame, wherein the first CTS frame is used to represent that the base station allocates a channel to the third terminal, The second CTS frame is used to indicate that if the target terminal contends for the channel, it informs the target terminal that the base station has successfully received the second data.

3) ACK frame, an affirmative acknowledgment frame required for data transmission; in this embodiment of the present invention, the ACK frame may include a first ACK frame and a second ACK frame, where the first ACK frame is used to indicate that the base station allocates a channel to the first ACK frame. For the second terminal, the second ACK frame is used to inform the third terminal that the transmission of the second data ends if there is no target terminal contending for the channel.

4) IBFD in-band full duplex, wireless communication allows nodes to transmit and receive simultaneously on the same frequency band.

Based on the foregoing content, an embodiment of the present invention provides a channel contention method for multi-terminal access. Referring to FIG. 1 , the method includes the following steps:

Step 101: If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the second RTS frame sent by the second terminal.

Among them, i is a positive integer greater than or equal to 1.

In the embodiment of the present invention, if the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal occupy the first channel of IBFD communication to perform the i-th data transmission, and the second terminal performs random access, The second RTS frame is sent to the base station, and then the base station receives the second RTS frame sent by the second terminal. That is, the premise of the access of the second terminal is that the second terminal only receives the handshake signal between the base station and the first terminal, and does not receive the response signal of the first terminal. Here, the handshake signal includes an RTS frame and a CTS frame, and the response signal is used to represent a signal that the i-th data transmission between the base station and the first terminal has been completed. In the embodiment of the present invention, after the second terminal sends the first RTS frame to the base station as an access request, there is still subsequent data transmission between the base station and the first terminal.

Step 102: If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal.

The first ACK frame is used to represent that the base station allocates the channel to the second terminal.

In this embodiment of the present invention, if the base station determines that the i-th data transmission between itself and the first terminal has been completed, the base station sends the first ACK frame to the second terminal. At this time, the base station allocates the second channel of the IBFD communication to the second terminal.

Step 103: If the base station and the first terminal perform the i+1th data transmission, the base station receives the first data sent by the second terminal.

In the embodiment of the present invention, after the base station allocates the second channel to the second terminal, when the base station and the first terminal perform the i+1th data transmission, the base station receives the first data sent by the second terminal.

In the channel contention method for multi-terminal access provided by the embodiment of the present invention, if the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, the second terminal receives the The second RTS frame sent; wherein, i is a positive integer greater than or equal to 1; if the i-th data transmission between the base station and the first terminal has been completed, the first ACK frame is sent to the second terminal; wherein, the first ACK The frame is used to indicate that the base station allocates the channel to the second terminal; if the base station and the first terminal perform the i+1th data transmission, the first data sent by the second terminal is received; that is, the base station and the first terminal are in the process of During the i-th data transmission, if the base station receives the second RTS frame sent by other terminals such as the second terminal, the base station will send the second terminal to the second terminal after the data transmission between itself and the first terminal is completed. Give the first ACK frame to the second terminal, so that after the second terminal receives the first ACK frame, when the base station and the first terminal perform the i+1th data transmission, send the first ACK frame to be transmitted to the base station through another channel data, and then the base station receives the first data. In this way, the base station uses a polling method for scheduling, which avoids channel contention during random access by multiple terminals, and solves the problem of data interaction between multiple terminals and the base station through random access in the related art. The problem of channel contention occurs when the base station allocates channels by polling, allowing two terminals to transmit and receive data at the same time without interfering with each other, which can fully improve the network throughput performance of the cell-based communication system.

Based on the foregoing embodiments, an embodiment of the present invention provides a channel contention method for multi-terminal access. Referring to FIG. 2 , the method includes the following steps:

Step 201: If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are conducting the i-th data transmission, the base station receives the second RTS frame sent by the second terminal, and the base station receives the data sent by the third terminal. The third RTS frame.

Among them, i is a positive integer greater than or equal to 1.

In this embodiment of the present invention, if the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal occupy the first channel of IBFD communication to perform the i-th data transmission, the second terminal and the third terminal perform random Access, send the second RTS frame and the third RTS frame to the base station; then, the base station receives the second RTS frame sent by the second terminal and the third RTS frame sent by the third terminal. That is to say, the premise of the access of the second terminal and the third terminal is that both the second terminal and the third terminal only receive the handshake signal between the base station and the first terminal, and do not receive the response signal from the first terminal. Here, the handshake signal includes an RTS frame and a CTS frame, and the response signal is used to represent a signal that the i-th data transmission between the base station and the first terminal has been completed. In this embodiment of the present invention, after the second terminal and the third terminal send the first RTS frame to the base station as an access request, there is still subsequent data transmission between the base station and the first terminal.

Step 202: If the i-th data transmission between the base station and the first terminal is completed, the base station sends the first ACK frame to the second terminal and the third terminal.

In this embodiment of the present invention, if the base station determines that the i-th data transmission between itself and the first terminal has been completed, the base station sends the first ACK frame to the second terminal and the third terminal. At this time, the first ACK frame is used to instruct the base station of the second terminal and the third terminal to allocate the second channel of the IBFD communication to the second terminal.

Step 203: The base station acquires the reception time of the second RTS frame and the reception time of the third RTS frame.

In the embodiment of the present invention, the base station obtains the receiving time of itself receiving the second RTS frame and the receiving time of receiving the third RTS frame, and sets the time between the multi-terminals based on the receiving time of the second RTS frame and the receiving time of the third RTS frame. priority relationship. Of course, in this embodiment of the present invention, the base station may also obtain the sending time of the second RTS frame sent by the second terminal and the sending time of the third RTS frame sent by the third terminal; and based on the sending time of the second RTS frame and the third RTS frame The transmission time of the frame sets the priority relationship between multiple terminals.

Step 204: If the receiving time of the second RTS frame is earlier than the receiving time of the third RTS frame, the base station sends the first ACK frame to the second terminal.

In this embodiment of the present invention, if the base station determines that the reception time of the second RTS frame is earlier than the reception time of the third RTS frame, the base station determines that the priority of the second terminal is higher than the priority of the third terminal, and sends a message to the second terminal. The first ACK frame. The first ACK frame is used to represent that the base station allocates the second channel to the second terminal.

Step 205: If the base station and the first terminal perform the i+1th data transmission, the base station receives the first data sent by the second terminal.

In this embodiment of the present invention, during the next data transmission process between the base station and the first terminal, the first data transmission is implemented between the base station and the second terminal through a second channel.

Step 206, the base station sends the first CTS frame to the third terminal.

Wherein, the first CTS frame is used to represent that the base station allocates the channel to the third terminal.

In the embodiment of the present invention, after the transmission of the first data between the base station and the second terminal is completed, the base station sends the first CTS frame to the third terminal, which is used to inform the third terminal to allocate the second channel to the third terminal at this time. Three terminals.

Step 207: If the base station and the first terminal perform the i+2th data transmission, the base station receives the second data sent by the third terminal.

In the embodiment of the present invention, during the next data transmission process between the base station and the first terminal, the second data transmission is implemented between the base station and the third terminal through the second channel.

Step 208: If the base station receives the third RTS frame sent by the target terminal, the base station sends the second CTS frame to the target terminal.

The second CTS frame is used to indicate that the base station has successfully received the second data; the target terminal includes the second terminal, the third terminal or the fourth terminal, and the fourth terminal is different from the first terminal, the second terminal and the third terminal .

In the embodiment of the present invention, after the transmission of the first data between the base station and the second terminal is completed, if the base station receives the third RTS frame sent by the target terminal, the base station sends the second CTS frame to the target terminal to inform the target terminal The terminal now allocates the second channel to the target terminal.

Step 209: If the base station does not receive the third RTS frame, the base station sends the second ACK frame to the third terminal.

The second ACK frame is used to indicate that the base station has successfully received the second data.

In the embodiment of the present invention, after the transmission of the first data between the base station and the second terminal is completed, if the base station does not receive the third RTS frame sent by the target terminal, the base station sends the second ACK frame to the third terminal for use in Notify the third terminal that the transmission of the second data is over.

It should be noted that, for the description of the same steps and the same content in this embodiment as in other embodiments, reference may be made to the descriptions in other embodiments, and details are not repeated here.

Based on the foregoing embodiments, a channel contention method for multi-terminal access provided by an embodiment of the present invention is further described. Referring to FIG. 3 , the method includes the following steps:

Here, it should be noted that, in the embodiment of the present invention, the method for resolving channel contention for multi-terminal random access in cell-based IBFD is mainly divided into two parts: multi-terminal random access control and base station polling scheduling.

The multi-terminal access process is shown in Figure 4. The base station (the base station corresponds to the node 0 in Figure 4) and the terminal 1 (the terminal 1 corresponds to the node 1 in Figure 4) occupy the first channel of IBFD communication, and the terminal 2 (the terminal 2 Corresponding to node 2 in FIG. 4 ) and terminal 3 (terminal 3 corresponding to node 3 in FIG. 4 ) perform random access at the same time. The premise of access is that the terminal 2 only receives the handshake signal between the base station and the terminal 1, and does not receive the response signal from the terminal 1. After the access request is sent, there is still data transmission between the base station and the terminal 1 subsequently. If the terminal 2 needs to send data to the base station, it needs to be done in the next data transmission process between the base station and the terminal 1, and the terminal 3 needs to be in the next data transmission process between the base station and the terminal 1. Schedule by query.

FIG. 5 is used to understand a communication scenario of multi-terminal access in the embodiment of the present invention. 51 points to node 0, which is the base station, 52 points to node 1, which is terminal 1 (terminal 1 is also called the first terminal). Both node 0 and node 1 correspond to the same time axis; the base station continuously sends data to node 1. In this communication scenario, 53 points to node 2, which is terminal 2 (terminal 2 is also called the second terminal) and 54 points to node 3, which is terminal 3 (terminal 3 is also called the third terminal), so that node 2 and node 3 need data. Taking sending to node 0 as an example, the random access control process is first performed according to FIG. 5 .

FIG. 5 is a sequence diagram of random access control of multiple terminals in an embodiment of the present invention. According to the channel contention method for multi-terminal access proposed by the embodiment of the present invention, the specific steps for nodes 2 and 3 to participate in communication are as follows:

Step 1: As shown in Figure 5, node 0 communicates with node 1, and node 2 and node 3 have data to send to node 0, so node 2 and node 3 use random back-off methods to back off W and W ₁ respectively. 0 sends control information for requesting access, which corresponds to the process indicated by 55 in FIG. 5 . Back-off duration W=W _min +mT _RTS , W ₁ =W _min +nT _RTS , where W _min represents the shortest back-off time of the terminal during the access process, T _RTS represents the transmission delay of RTS, m and n represent random points selection.

Step 2: Node 2 preferentially sends RTS to node 0, so node 0 prioritizes scheduling and assigning channels to node 1. After node 2 receives the ACK feedback from node 0, it waits for the next RTS handshake signal sent by node 0 to node 1, node 2 After waiting for M time, data is sent to node 0, which corresponds to the process indicated by 56 in FIG. 5 . The reference value of the waiting time is: M=W _min =2×SIFS+T _CTS , where W _min represents the shortest back-off time of the terminal during the access process, SIFS represents the minimum inter-frame interval, and T _CTS represents the transmission delay of the CTS;

Step 3: Node 3 also sends the access request information to Node 0 in the process indicated by 55 in FIG. 5 . After the node 2 finishes sending the data, the node 0 preferentially schedules and allocates the channel to the node 3 during the next data transmission with the node 1. After receiving the RTS reply from node 0, node 3 backs off for M duration, occupies the channel and sends data to node 0, corresponding to the process indicated by 57 in FIG. 5 .

Combined with the above content, the operations performed by the base station during the channel contention process of multi-terminal access are briefly described:

Step 301, the base station receives the RTS frame sent by the first terminal, and the base station and the first terminal are performing data transmission.

Step 302, the base station listens to the RTS frames sent by other terminals except the first terminal. If the RTS frame sent by the other terminal is detected, the next step is performed.

Step 303: The base station sends an ACK frame to the second terminal with a high priority according to the priorities of other terminals, and then performs the next step. Here, the other terminals include the second terminal.

Step 304: The base station determines whether the data DATA of the second terminal is received. If the data DATA of the second terminal is received, proceed to the next step; otherwise, jump to step 302, and continue to monitor the RTS frames of other terminals.

In this embodiment of the present invention, it can be understood that the priorities of multiple terminals may be set based on the time point when each terminal sends an RTS frame as control information for requesting access and the number of times the terminal occupies a channel to send data. For example, the priority of the terminal may be performed in a first-come-first-served manner, and the priority of the terminal that has been served, that is, occupies the channel and transmits data, is reduced.

Step 305: After receiving the data of the second terminal, the base station determines whether there is a third terminal with a low priority that continues to contend for the channel.

Further, if there is a low-priority terminal contending for a channel, step 306 is executed, and the base station sends a CTS to the low-priority terminal to allow the low-priority terminal to send data.

Further, if there is no low-priority terminal contending for the channel, step 307 is performed, and an ACK is sent to the high-priority terminal to confirm the data.

It can be seen that multiple terminals use random backoff to contend for channels with the base station, and the base station uses a polling manner to allocate channels when receiving multiple access requests. The process design can avoid the invalid occupation of the full-duplex transmission resources of the base station by multiple terminals, thereby improving the utilization rate of the channel and the throughput performance of the system.

It can be seen from the above that for cell-based IBFD wireless communication, the base station sends data to the first terminal along the first channel; the second terminal and the third terminal send request information for accessing the second channel to the base station, and the two terminals use random backoff. The access request information is sent by the second terminal, and if the base station is in the data transmission phase and has the IBFD communication capability, the base station first receives the request information from the second terminal and then sends the access request information. Set the second terminal to be a high-priority terminal, and set the third terminal to be a low-priority terminal; then, in the next data transmission process with the first terminal, the base station schedules the second terminal to send data; finally, the second terminal After the data is sent, the base station schedules the third terminal to send data during the next data transmission process of the first terminal. In cell-based communication, multiple terminals send request information to the base station at the same time for channel contention, the terminal uses random backoff to send access request control information, and the base station uses round-robin scheduling to allocate channels, thereby reducing the number of Terminal control information and collision probability of data transmission. The present invention can be effectively applied to the cell-based IBFD wireless communication, fully utilizes the advantage of IBFD to transmit data at the same frequency at the same time, and improves the throughput performance of the wireless communication system.

Based on the foregoing embodiments, an embodiment of the present invention provides a channel contention method for multi-terminal access. Referring to FIG. 6 , the method includes the following steps:

Step 401: If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, the second terminal sends the second RTS frame to the base station after waiting for the first time period.

Among them, i is a positive integer greater than or equal to 1. Here, the first duration can be represented by W, W=W _min +mT _RTS ; wherein, W _min represents the shortest backoff time of the terminal in the access process, T _RTS represents the transmission delay of RTS, and m represents the selection of random points .

Step 402: The second terminal receives the first ACK frame fed back by the base station for the second RTS frame.

The first ACK frame is used to represent that the base station allocates the channel to the second terminal.

In the embodiment of the present invention, based on the first ACK frame, the second terminal confirms that the base station allocates the second channel to itself to realize data transmission.

Step 403: If the base station and the first terminal perform the i+1th data transmission, the second terminal sends the first data to the base station based on the first ACK frame.

In this embodiment of the present invention, in step 403, if the base station and the first terminal perform the i+1th data transmission, send the first data to the base station based on the first ACK frame, including: if the third data transmission sent by the base station to the first terminal is received After the RTS frame and waiting for the second time period, the base station and the first terminal perform the i+1th data transmission, and send the first data to the base station based on the first ACK frame. That is to say, after the second terminal receives the third RTS frame sent by the base station to the first terminal and waits for the second time period, in the process of performing the i+1th data transmission between the first terminal and the base station, the second terminal sends the data to the base station. Send the first data. Here, the second duration is represented by M, M=W _min =2×SIFS+T _CTS ; wherein, W _min represents the shortest back-off time of the terminal in the access process, SIFS represents the minimum inter-frame interval, and T _CTS represents the transmission delay of CTS .

It should be noted that, for the description of the same steps and the same content in this embodiment as in other embodiments, reference may be made to the descriptions in other embodiments, and details are not repeated here.

Based on the foregoing embodiments, an embodiment of the present invention provides a channel contention method for multi-terminal access. Referring to FIG. 7 , the method includes the following steps:

Step 501: If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, the third terminal sends a fourth RTS frame to the base station after waiting for a third time period.

The third duration is greater than the first duration, and i is a positive integer greater than or equal to 1.

Here, the third duration can be represented by W ₁ , W ₁ =W _min +nT _RTS ; wherein, W _min represents the shortest back-off time of the terminal during the access process, T _RTS represents the transmission delay of the RTS, and n represents the random point selection.

Step 502: The third terminal receives the first CTS frame fed back by the base station for the fourth RTS frame.

Wherein, the first CTS frame is used to represent that the base station allocates the channel to the third terminal.

In the embodiment of the present invention, based on the first CTS frame, the third terminal confirms that the base station has allocated the second channel to itself to realize data transmission.

Step 503: If the base station and the first terminal perform the i+2th data transmission, the third terminal sends the second data to the base station based on the first CTS frame.

In this embodiment of the present invention, in step 503, if the base station and the first terminal perform the i+2th data transmission, send the second data to the base station based on the first CTS frame, including: if the fifth data transmission sent by the base station to the first terminal is received After the RTS frame and waiting for the fourth time period, the base station and the first terminal perform the i+2 th data transmission, and based on the first CTS frame, the second data is sent to the base station. That is to say, after the third terminal receives the fifth RTS frame sent by the base station to the first terminal and waits for the fourth time period, in the process of performing the i+2th data transmission between the first terminal and the base station, the third terminal sends the data to the base station. Send second data. Here, the fourth duration can also be represented by M, M=W _min =2×SIFS+T _CTS ; wherein, W _min represents the shortest back-off time of the terminal in the access process, SIFS represents the minimum inter-frame interval, and T _CTS represents the transmission of CTS time delay.

Step 504: The third terminal receives a second CTS frame indicating that the base station has successfully received the second data; or, the third terminal receives a second ACK frame indicating that the base station has successfully received the second data.

In this embodiment of the present invention, if there is a low-priority terminal contending for the channel relative to the third terminal, the third terminal receives the second CTS frame indicating that the base station has successfully received the second data. In this scenario, The second CTS frame has a similar function to the first CTS frame, that is, the base station sends the second CTS frame to the low-priority terminal to inform the low-priority terminal that a channel is allocated to it.

If there is no low-priority terminal contending for the channel, the third terminal receives a second ACK frame indicating that the base station has successfully received the second data.

Based on the above content, it can be seen that the channel contention method for multi-terminal access provided by the embodiment of the present invention can achieve the following beneficial effects:

(1) Provide a channel contention solution method for random access of multi-terminal IBFD in a cell system. Multi-terminal monitors the IBFD wireless communication capability of the base station by means of random backoff. The base station allocates channels by polling, allowing two Each terminal simultaneously transmits and receives data in a way that does not interfere with each other, which can fully improve the network throughput performance of the cell-based communication system.

(2) After the cell-based IBFD multi-terminal is accessed, the control method of the interaction between the control frame and the data frame effectively solves the problem of channel conflict.

(3) The cell-based IBFD access control method is not only suitable for full-duplex communication, but also compatible with half-duplex communication, thereby effectively improving the network throughput performance of the communication system.

(4) Compared with the single-terminal probe access, the situation is more complicated for the cell-based IBFD multi-terminal probe access, and the method provided by the embodiment of the invention can effectively solve the problem of collision of transmission frames.

(5) The method provided by the embodiment of the present invention can solve the problem of contention of channel resources by multiple terminals in a cell-based networking.

(6) The method provided by the embodiment of the present invention can solve the problem of conflict between control frames (control frames such as ACK frames) and data frames interacted between different terminals and base stations on the same channel.

(7) The method provided by the embodiment of the present invention can use the active polling method of the base station to perform channel allocation to the priorities of multiple terminals.

(8) The method provided by the embodiment of the present invention considers the compatibility between IBFD communication and traditional half-duplex communication.

(9) The method provided by the embodiment of the present invention is aimed at multi-terminal detection access, rather than single-terminal detection access, and can solve the conflict problem of multi-terminal detection access.

It should be noted that, for the description of the same steps and the same content in this embodiment as in other embodiments, reference may be made to the descriptions in other embodiments, and details are not repeated here.

Based on the foregoing embodiments, an embodiment of the present invention provides a base station 7, and the base station 7 can be applied to a channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 1-2, with reference to the method shown in FIG. 8 , the base station 7 includes: a first processor 71, a first memory 72 and a first communication bus 73, wherein:

The first communication bus 73 is used to realize the communication connection between the first processor 71 and the first memory 72;

The first processor 71 is configured to execute the channel contention program for multi-terminal access in the first memory 72, so as to realize the following steps:

If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are conducting the i-th data transmission, receive the second RTS frame sent by the second terminal; wherein, i is a positive integer greater than or equal to 1;

If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal; wherein, the first ACK frame is used to indicate that the base station allocates a channel to the second terminal;

If the base station and the first terminal perform the i+1th data transmission, the first data sent by the second terminal is received.

In other embodiments of the present invention, the first processor 71 is configured to execute the channel contention program for multi-terminal access in the first memory 72, and may implement the following steps:

If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the third RTS frame sent by the third terminal;

Correspondingly, if the i-th data transmission between the base station and the first terminal has been completed, the first ACK frame is sent to the second terminal, including:

If the i-th data transmission between the base station and the first terminal has been completed, send the first ACK frame to the second terminal and the third terminal;

Correspondingly, if the base station performs the i+1th data transmission with the first terminal, and receives the first data sent by the second terminal, including:

Obtain the reception time of the second RTS frame and the reception time of the third RTS frame;

If the reception time of the second RTS frame is earlier than the reception time of the third RTS frame, send the first ACK frame to the second terminal;

If the base station and the first terminal perform the i+1th data transmission, the first data sent by the second terminal is received.

In other embodiments of the present invention, the first processor 71 is configured to execute the channel contention procedure for multi-terminal access in the first memory 72, so as to realize the following steps:

sending the first CTS frame to the third terminal; wherein, the first CTS frame is used to represent that the base station allocates the channel to the third terminal;

If the base station and the first terminal perform the i+2th data transmission, the second data sent by the third terminal is received.

In other embodiments of the present invention, the first processor 71 is configured to execute the channel contention procedure for multi-terminal access in the first memory 72, so as to realize the following steps:

If the base station receives the third RTS frame sent by the target terminal, it sends the second CTS frame to the target terminal; wherein, the second CTS frame is used to indicate that the base station has successfully received the second data; the target terminal includes the second terminal, the third terminal Or a fourth terminal, where the fourth terminal is different from the first terminal, the second terminal and the third terminal.

In other embodiments of the present invention, the first processor 71 is configured to execute the channel contention procedure for multi-terminal access in the first memory 72, so as to realize the following steps:

If the base station does not receive the third RTS frame, it sends a second ACK frame to the third terminal, wherein the second ACK frame is used to indicate that the base station has successfully received the second data.

It should be noted that, for the specific implementation process of the steps executed by the processor in this embodiment, reference may be made to the implementation process in the channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 1-2 , which is not repeated here. Repeat.

Based on the foregoing embodiments, an embodiment of the present invention provides a second terminal 8, which can be applied to a channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 6 , with reference to FIG. 9 . As shown, the second terminal 8 includes: a second processor 81, a second memory 82 and a second communication bus 83, wherein:

The second communication bus 83 is used to realize the communication connection between the second processor 81 and the second memory 82;

The second processor 81 is configured to execute the channel contention program for multi-terminal access in the second memory 82, so as to realize the following steps:

If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are conducting the i-th data transmission, after waiting for the first time period, the second RTS frame is sent to the base station; wherein, i is greater than or equal to 1 positive integer of ;

receiving the first ACK frame fed back by the base station for the second RTS frame; wherein the first ACK frame is used to represent that the base station allocates a channel to the second terminal;

If the base station and the first terminal perform the i+1th data transmission, the first data is sent to the base station based on the first ACK frame.

In this embodiment of the present invention, the second processor 81 is configured to execute a channel contention program for multi-terminal access in the second memory 82, so as to implement the following steps:

If the third RTS frame sent by the base station to the first terminal is received and after waiting for the second duration, and the base station and the first terminal perform the i+1th data transmission, the first data is sent to the base station based on the first ACK frame.

It should be noted that, for the specific implementation process of the steps executed by the processor in this embodiment, reference may be made to the implementation process in the channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 6 , and details are not repeated here.

Based on the foregoing embodiments, an embodiment of the present invention provides a third terminal 9, and the third terminal 9 can be applied to a channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 7 , referring to FIG. 10 . As shown, the third terminal 9 includes: a third processor 91, a third memory 92 and a third communication bus 93, wherein:

The third communication bus 93 is used to realize the communication connection between the third processor 91 and the third memory 92;

The third processor 91 is configured to execute the channel contention procedure for multi-terminal access in the third memory 92, so as to realize the following steps:

If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are conducting the i-th data transmission, after waiting for the third time period, the fourth RTS frame is sent to the base station; a duration; i is a positive integer greater than or equal to 1;

receiving the first CTS frame fed back by the base station for the fourth RTS frame; wherein the first CTS frame is used to represent that the base station allocates the channel to the third terminal;

If the base station and the first terminal perform the i+2th data transmission, the second data is sent to the base station based on the first CTS frame.

In this embodiment of the present invention, the third processor 91 is configured to execute a channel contention program for multi-terminal access in the third memory 92, so as to implement the following steps:

If the fifth RTS frame sent by the base station to the first terminal is received and after waiting for the fourth time period, and the base station and the first terminal perform the i+2th data transmission, the second data is sent to the base station based on the first CTS frame.

In this embodiment of the present invention, the third processor 91 is configured to execute a channel contention program for multi-terminal access in the third memory 92, so as to implement the following steps:

A second CTS frame is received to indicate that the base station has successfully received the second data; or, a second ACK frame is received to indicate that the base station has successfully received the second data.

It should be noted that, for the specific implementation process of the steps executed by the processor in this embodiment, reference may be made to the implementation process in the channel contention method for multi-terminal access provided by the embodiment corresponding to FIG. 7 , which will not be repeated here.

Based on the foregoing embodiments, embodiments of the present invention provide a computer-readable storage medium, where the computer-readable storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to The steps of implementing the channel contention method for multi-terminal access provided by the embodiments corresponding to FIG. 1-2 or 6 or 7 are implemented.

It should be noted that the above-mentioned computer-readable storage medium may be a read-only memory (Read Only Memory, ROM), a programmable read-only memory (Programmable Read-Only Memory, PROM), an erasable programmable read-only memory (Erasable Programmable read only memory, ROM) Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Magnetic Random Access Memory (FRAM), Flash Memory (Flash Memory) , magnetic surface memory, optical disk, or memory such as Compact Disc Read-Only Memory (CD-ROM); it can also be a variety of electronic devices including one or any combination of the above memories, such as mobile phones, computers, tablet devices, personal digital assistants, etc.

It should be noted that, herein, the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements, It also includes other elements not expressly listed or inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

The above-mentioned serial numbers of the embodiments of the present invention are only for description, and do not represent the advantages or disadvantages of the embodiments.

From the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus a necessary general hardware platform, and of course hardware can also be used, but in many cases the former is better implementation. Based on this understanding, the technical solutions of the present invention can be embodied in the form of software products in essence or the parts that make contributions to the prior art, and the computer software products are stored in a storage medium (such as ROM/RAM, magnetic disk, CD-ROM), including several instructions to make a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flows of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

The above are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields , are similarly included in the scope of patent protection of the present invention.

Claims (13)

1. A channel contention method for multi-terminal access, wherein the method is applied to a base station, and the method comprises: If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the second RTS frame sent by the second terminal; wherein the i is a positive integer greater than or equal to 1; If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal; wherein, the first ACK frame is used to indicate that the base station allocates a channel to the second terminal; If the base station performs the i+1th data transmission with the first terminal, the first data sent by the second terminal is received. 2. The method according to claim 1, wherein the method further comprises: If the base station receives the first RTS frame sent by the first terminal, and the base station and the first terminal are performing the i-th data transmission, receive the third RTS frame sent by the third terminal; Correspondingly, if the i-th data transmission between the base station and the first terminal has been completed, sending the first ACK frame to the second terminal includes: If the i-th data transmission between the base station and the first terminal has been completed, send a first ACK frame to the second terminal and the third terminal; Correspondingly, the receiving the first data sent by the second terminal if the base station performs the i+1th data transmission with the first terminal includes: Obtain the reception time of the second RTS frame and the reception time of the third RTS frame; If the receiving time of the second RTS frame is earlier than the receiving time of the third RTS frame, sending a first ACK frame to the second terminal; If the base station performs the i+1th data transmission with the first terminal, the first data sent by the second terminal is received. 3. The method according to claim 2, wherein, after receiving the first data sent by the second terminal after the base station and the first terminal perform the i+1th data transmission, the The method also includes: sending a first CTS frame to the third terminal; wherein the first CTS frame is used to represent that the base station allocates a channel to the third terminal; If the base station performs the i+2th data transmission with the first terminal, the second data sent by the third terminal is received. 4. The method according to claim 3, wherein after receiving the second data sent by the third terminal after the base station and the first terminal perform the i+2th data transmission, the The method also includes: If the base station receives the third RTS frame sent by the target terminal, it sends a second CTS frame to the target terminal; wherein, the second CTS frame is used to indicate that the base station has successfully received the second data; The target terminal includes the second terminal, the third terminal or the fourth terminal, and the fourth terminal is different from the first terminal, the second terminal and the third terminal. 5. The method according to claim 4, wherein the method further comprises: If the base station does not receive the third RTS frame, it sends a second ACK frame to the third terminal, wherein the second ACK frame is used to indicate that the base station has successfully received the second data. 6. A channel contention method for multi-terminal access, wherein the method is applied to a second terminal, and the method comprises: If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, the second RTS frame is sent to the base station after waiting for the first time period; wherein , the i is a positive integer greater than or equal to 1; receiving the first ACK frame fed back by the base station for the second RTS frame; wherein, the first ACK frame is used to represent that the base station allocates a channel to the second terminal; If the base station and the first terminal perform the i+1th data transmission, send the first data to the base station based on the first ACK frame. 7 . The method according to claim 6 , wherein, if the base station and the first terminal perform the i+1th data transmission, send the first ACK frame to the base station based on the first ACK frame. 8 . 1 data, including: If after receiving the third RTS frame sent by the base station to the first terminal and waiting for a second time period, the base station and the first terminal perform the i+1th data transmission, based on the first ACK frame, and send the first data to the base station. 8. A channel contention method for multi-terminal access, wherein the method is applied to a third terminal, and the method comprises: If the first RTS frame sent by the first terminal to the base station is received, and the first terminal and the base station are performing the i-th data transmission, after waiting for a third time period, a fourth RTS frame is sent to the base station; wherein , the third duration is greater than the first duration; the i is a positive integer greater than or equal to 1; receiving the first CTS frame fed back by the base station for the fourth RTS frame; wherein the first CTS frame is used to represent that the base station allocates a channel to the third terminal; If the base station and the first terminal perform the i+2th data transmission, send second data to the base station based on the first CTS frame. 9 . The method according to claim 8 , wherein, if the base station and the first terminal perform the i+2th data transmission, based on the first CTS frame, send the th Two data, including: If after receiving the fifth RTS frame sent by the base station to the first terminal and waiting for a fourth time period, the base station and the first terminal perform the i+2th data transmission, based on the first CTS frame, and send the second data to the base station. 10 . The method according to claim 9 , wherein, after receiving a fifth RTS frame sent by the base station to the first terminal and waiting for a fourth time period, the base station and the first terminal After a terminal performs the i+2th data transmission and sends the second data to the base station based on the first CTS frame, the method further includes: A second CTS frame is received to indicate that the base station has successfully received the second data; or, a second ACK frame is received to indicate that the base station has successfully received the second data. 11. A base station, characterized in that the base station comprises: a first processor, a first memory and a first communication bus; The first communication bus is used to realize the communication connection between the first processor and the first memory; The first processor is configured to execute the channel contention program for multi-terminal access in the first memory, so as to implement the steps of the channel contention method for multi-terminal access according to any one of claims 1 to 5. 12. A second terminal, characterized in that the second terminal comprises: a second processor, a second memory and a second communication bus; The second communication bus is used to realize the communication connection between the second processor and the second memory; The second processor is configured to execute the channel contention program for multi-terminal access in the second memory, so as to implement the steps of the channel contention method for multi-terminal access according to any one of claims 6 to 7. 13. A third terminal, characterized in that the third terminal comprises: a third processor, a third memory and a third communication bus; The third communication bus is used to realize the communication connection between the third processor and the third memory; The third processor is configured to execute the channel contention program for multi-terminal access in the third memory, so as to implement the steps of the channel contention method for multi-terminal access according to any one of claims 8 to 10.

Images