CN105491671B - A kind of multiple terminals uplink dispatch method and the network system based on license supplementary access - Google Patents

Abstract

The embodiment of the present invention discloses a multi-terminal uplink scheduling method and a network system based on grant-assisted access. The first OFDM symbol in the first subframe of the data frame to be transmitted uplink The cyclic prefix and the cyclic prefix of the last OFDM symbol of the subframe currently being transmitted are shortened, so that the terminal that is currently transmitting uplink data is prevented from communicating with other terminals within the time corresponding to the shortened cyclic prefix. Interference is caused by idle channel assessment and detection, and in the absence of other interference sources, other terminals can perform uplink data transmission without waiting for the subframe pre-configured by the base station to perform channel state detection, thereby reducing delay and improving scheduling Flexibility improves channel resource utilization.

Description

A multi-terminal uplink scheduling method and network system based on grant-assisted access

technical field

The invention relates to the field of communication technology, in particular to a multi-terminal uplink scheduling method and a network system based on permission-assisted access.

Background technique

Different spectrums of wireless electromagnetic waves are divided for use by GSM (Global System for Mobile Communication, Global System for Mobile Communications), LTE, digital trunking, radio and television, etc. Each country will divide it for each operator in the country according to its own resources Spectrum, this part of the spectrum is called the licensed spectrum, and the rest of the spectrum that has not been used or approved for public use is the unlicensed spectrum.

At present, in order to make full use of unlicensed spectrum resources to expand the LTE network based on the LAA (License Assisted Access, License Assisted Access) technology, there are two methods for uplink scheduling of multiple terminals.

The first method is: the base station independently schedules all terminals in the system, sends an authorization for each terminal, and the terminal determines the time for channel state detection by itself according to the authorization. For each terminal, when it detects that the channel state is idle, the terminal can perform uplink transmission; otherwise, the base station will fail to perform this scheduling, and the terminal cannot perform uplink transmission. The new authorization determines the time for itself to perform channel state detection, and so on).

The second way is: in a radio frame, the base station pre-configures a series of subframes, and only in these subframes, all terminals in the system can perform channel state detection. For each terminal, when it detects that the channel state is idle, the terminal can perform uplink transmission; otherwise, it can only wait until the next subframe where channel state detection can be performed to perform channel state detection, that is, the base station schedules the terminal again in the next A subframe capable of performing channel state detection performs channel state detection.

However, the above-mentioned first method is used to perform uplink scheduling for multiple terminals, and the terminals to be uplink data transmission perform channel state detection before uplink transmission. The data transmission frequency of the terminal is different from the data transmission frequency of the terminal currently transmitting the uplink data. The terminal waiting for the uplink data transmission will also detect that the channel status is not idle, and cannot upload data frames, and the channel resource utilization rate is low. Low.

Apply the second method above to perform uplink scheduling for multiple terminals. The base station pre-configures a series of subframes, and the terminal can only perform channel state detection in these subframes, that is, the terminal to be uplink transmission can only perform channel state detection at a specific moment. detection for uplink transmission. Therefore, when the terminal does not have data to transmit in these pre-configured subframes, it can only perform channel state detection until the next subframe that can perform channel state detection, or when a certain terminal can perform channel state detection. When it is detected that the channel state is not idle in a subframe, the channel state detection can only be performed after the next subframe in which the channel state detection can be performed, resulting in an increase in the time delay.

Contents of the invention

The purpose of the embodiments of the present invention is to provide a multi-terminal uplink scheduling method and a network system based on grant-assisted access, so as to reduce time delay, improve channel resource utilization and reduce channel resource waste.

In order to achieve the above purpose, the embodiment of the present invention discloses a multi-terminal uplink scheduling method, which is applied to a network system based on grant-assisted access. The network system includes N terminals and a base station, wherein the N terminals share a The channel performs data communication with the base station, each of the N terminals obtains in advance an authorization from the base station for uploading data frames of the terminal, and the authorization includes an upload data frequency for the terminal to upload data frames, Each terminal in the N terminals determines the start uploading time of the data frame uploaded by itself according to the received authorization license;

The method can include:

After each of the N terminals establishes a data communication connection with the base station, the base station sends a first scheduling instruction to the terminal through a radio resource control protocol, and the first scheduling instruction includes shortening the waiting period of the terminal. Information about the cyclic prefix of the first OFDM symbol in the first subframe of the data frame for uplink data transmission and the cyclic prefix of the last OFDM symbol in all subframes ;

According to the first scheduling instruction, the terminal shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted by the terminal, so that the The transmission duration of the first subframe is reduced by T1 duration;

According to the first scheduling instruction, the terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by the terminal, so that the first The transmission duration of the subframe is further reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration, wherein the T2 duration is greater than the preset first duration, and the T1 duration is the same as the T1 duration The sum of the above T2 durations is greater than the preset second duration;

When there is an upload start time corresponding to the terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shortening the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted is equal to that of the terminal Within the duration of T1 corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted, the terminal performs idle channel assessment detection on the channel, and determines that it is waiting for transmitted data frames;

The terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the terminal upload data frame included in the authorization license.

The embodiment of the present invention also discloses a multi-terminal uplink scheduling method, which is applied to a network based on permission-assisted access technology. The network includes N terminals and a base station, wherein the N terminals share a channel with the base station For data communication, each of the N terminals obtains in advance an authorization from the base station for uploading data frames of the terminal, the authorization includes the upload data frequency of the terminal to upload data frames, and the N terminals Each terminal in the system determines the start uploading time of its own uploaded data frame according to the received authorization license;

The method can include:

When the base station determines that there is an upload start time in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted according to the start upload time of each terminal, determine the x number of data frames currently being transmitted. A terminal and y terminals to be used for uplink data transmission, wherein the y terminals are terminals corresponding to the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted;

The base station sends a second scheduling instruction to each of the x terminals in a dynamic uplink grant manner, and the second scheduling instruction includes shortening the last orthogonal frequency of the subframe that the terminal is currently transmitting. information on the cyclic prefix of the demultiplexed symbols;

The base station sends a third scheduling instruction to each of the y terminals in a dynamic uplink grant mode, and the third scheduling instruction includes shortening the first subframe of the data frame to be transmitted by the terminal Information about the cyclic prefix of the first OFDM symbol;

Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the subframe The transmission duration is reduced by T3 duration, wherein the T3 duration is greater than the preset third duration;

Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that The transmission duration of the subframe is reduced by T4 duration, wherein the sum of the T3 duration and the T4 duration is greater than a preset fourth duration;

Each of the y terminals performs idle channel assessment detection on the channel within the T3 time period and the T4 time period, and determines its own data frame to be transmitted;

Each of the y terminals transmits its own determined data frame to be transmitted according to the data upload frequency of the terminal uploading data frame included in the authorization license.

The embodiment of the present invention also discloses a permission-based assisted access network system, which may include: N terminals and a base station, wherein the N terminals share a channel for data communication with the base station;

The base station sends an authorization license for uploading data frames to each of the N terminals in advance, and the authorization license includes an upload data frequency of the terminal uploading data frames;

Each terminal in the N terminals obtains the authorization license sent by the base station for uploading data frames by its own terminal, and determines the start uploading time of its own upload data frame according to the received authorization license;

The base station sends a first scheduling instruction to each of the N terminals through a radio resource control protocol, and the first scheduling instruction includes shortening the first subframe of a data frame to be transmitted by the terminal for uplink data transmission Information about the cyclic prefix of the first OFDM symbol and the cyclic prefix of the last OFDM symbol of all subframes;

The first terminal that receives the first scheduling instruction sent by the base station, according to the first scheduling instruction, shortens the first orthogonal frequency division of the first subframe of the data frame to be transmitted by its own terminal to perform uplink data transmission. Multiplexing the cyclic prefix of the symbol, so that the transmission duration of the first subframe is reduced by T1 duration;

According to the first scheduling instruction, the first terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by its own terminal, so that the first The transmission duration of subframes is reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration, wherein the T2 duration is greater than the preset first duration, and the T1 duration is the same as The sum of the T2 durations is greater than the preset second duration;

When there is an upload start time corresponding to the first terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shorten the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted and Within the duration of T1 corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted shortened by the first terminal, the first terminal performs Idle channel assessment and detection, and determine the data frame to be transmitted;

The first terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the first terminal upload data frame included in the authorization.

The embodiment of the present invention also discloses a permission-based assisted access network system, which may include: N terminals and a base station, wherein the N terminals share a channel for data communication with the base station;

The base station sends an authorization license for uploading data frames to each of the N terminals in advance, and the authorization license includes an upload data frequency of the terminal uploading data frames;

Each terminal in the N terminals obtains the authorization license sent by the base station for uploading data frames by its own terminal, and determines the start uploading time of its own upload data frame according to the received authorization license;

When the base station determines that there is an upload start time in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted according to the start upload time of each terminal, determine the x number of data frames currently being transmitted. A terminal and y terminals to be used for uplink data transmission, wherein the y terminals are terminals corresponding to the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted;

The base station sends a second scheduling instruction to each of the x terminals in a dynamic uplink grant manner, and the second scheduling instruction includes shortening the last orthogonal frequency of the subframe that the terminal is currently transmitting. information on the cyclic prefix of the demultiplexed symbols;

The base station sends a third scheduling instruction to each of the y terminals in a dynamic uplink grant mode, and the third scheduling instruction includes shortening the first subframe of the data frame to be transmitted by the terminal Information about the cyclic prefix of the first OFDM symbol;

Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the subframe The transmission duration is reduced by T3 duration, wherein the T3 duration is greater than the preset third duration;

Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that The transmission duration of the subframe is reduced by T4 duration, wherein the sum of the T3 duration and the T4 duration is greater than a preset fourth duration;

Each of the y terminals performs idle channel assessment detection on the channel within the T3 time period and the T4 time period, and determines its own data frame to be transmitted;

Each of the y terminals transmits the determined data frame to be transmitted by itself according to the data upload frequency of the terminal uploading the data frame included in the authorization.

It can be seen from the above scheme that in this embodiment, the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted uplink data and the cyclic prefix of the subframe currently being transmitted The cyclic prefix of the last OFDM symbol is shortened, so as to prevent the terminal that is currently transmitting uplink data from interfering with other terminals in idle channel assessment and detection during the time corresponding to the shortened cyclic prefix, and In the absence of interference from other sources of interference, other terminals can perform uplink data transmission without waiting for the subframe pre-configured by the base station to perform channel state detection, thereby reducing delay, improving scheduling flexibility, and improving channel resource utilization.

Of course, implementing any product or method of the present invention does not necessarily need to achieve all the above-mentioned advantages at the same time.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic flowchart of a first kind of flow of a multi-terminal uplink scheduling method provided by an embodiment of the present invention;

FIG. 2 is a schematic flowchart of a second multi-terminal uplink scheduling method provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a first type of terminal transmission data frame provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a second type of terminal transmission data frame provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a permission-based assisted access network system provided by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In order to solve the problems in the prior art, an embodiment of the present invention provides a multi-terminal uplink scheduling method and a network system based on grant-assisted access. A multi-terminal uplink scheduling method provided by an embodiment of the present invention will firstly be described in detail below.

It should be noted that the multi-terminal uplink scheduling method provided by the embodiment of the present invention is preferably applicable to a network system based on grant-assisted access. In practical applications, the network system may be an LTE network system. The network system is shown in FIG. 5 . FIG. 5 is a schematic structural diagram of a permission-based assisted access network system provided by an embodiment of the present invention.

The network system may include N terminals and a base station, wherein the N terminals are respectively terminal 1, terminal 2, terminal 3 ... terminal N, and the N terminals share a channel for data communication with the base station, Each of the N terminals obtains in advance an authorization from the base station for uploading data frames of the terminal, the authorization includes an upload data frequency for the terminal to upload data frames, and each of the N terminals According to the received authorization, the terminal determines the start uploading time of the data frame uploaded by itself.

It should be noted that the terminal can perform uplink data transmission only under the condition of obtaining authorization from the base station.

FIG. 1 is a schematic flowchart of a first multi-terminal uplink scheduling method provided by an embodiment of the present invention, which may include:

S101: After each of the N terminals establishes a data communication connection with the base station, the base station sends a first scheduling instruction to the terminal through the radio resource control protocol, and the first scheduling instruction includes shortening the data to be transmitted by the terminal for uplink data Information about the cyclic prefix of the first OFDM symbol in the first subframe of the frame and the cyclic prefix of the last OFDM symbol in all subframes.

Specifically, the above radio resource control protocol may be RRC (Radio Resource Control), the Orthogonal Frequency Division Multiplexing symbol is OFDM (Orthogonal Frequency Division Multiplexing) symbol, the cyclic prefix is CP (Cyclic Prefix), and the duration of one subframe is 1 millisecond.

There are two ways in which the base station sends the first scheduling instruction to the terminal through the radio resource control protocol. The first type: After the terminal establishes a data communication connection with the base station for the first time, the base station sends the first scheduling instruction to the terminal. When the terminal needs to re-establish a data communication connection with the base station due to network failure, the base station no longer sends the first scheduling instruction to the terminal. . The second type: whenever the terminal establishes a data communication connection with the base station, the base station sends the first scheduling instruction to the terminal.

S102: According to the first scheduling instruction, the terminal shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted by the terminal, so that the first subframe The frame transmission duration is reduced by T1 duration.

S103: According to the first scheduling instruction, the terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by the terminal, so that the transmission of the first subframe The duration is further reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration.

Wherein, the T2 duration is greater than a preset first duration, and the sum of the T1 duration and the T2 duration is greater than a preset second duration.

In practical applications, the preset first duration may be 4 microseconds, and the second preset duration may be 9 microseconds.

S104: When there is an upload start time corresponding to the terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shorten the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted to match the Within the T1 duration corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted shortened by the terminal, the terminal performs idle channel assessment detection on the channel, and determines that it is waiting for The transmitted data frame.

S105: The terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the terminal upload data frame included in the authorization.

In the following, two terminals are taken as examples for description.

As shown in FIG. 3 , it is assumed that the start uploading time of the self-uploaded data frame determined by the terminal 1 is subframe #n+1, and the start uploading time of the self-uploaded data frame determined by the terminal 2 is subframe #n+2.

The base station sends the first scheduling instruction to the terminal 1 and the terminal 2 through RRC static configuration, and the first scheduling instruction includes shortening the first OFDM symbol of the first subframe of the data frame to be transmitted by the terminal. CP and the information of the CP of the last OFDM symbol of all subframes.

According to the first scheduling instruction sent by the base station, the terminal 1 and the terminal 2 respectively shorten the CP of the first OFDM symbol in the first subframe of the data frame to be transmitted by the terminal itself (that is, the T1 part in FIG. 3 ), and the CP of the last OFDM symbol of all subframes of the data frame to be transmitted for uplink data (that is, the T2 part in Figure 3), so that the transmission duration of the first subframe is reduced by T1+T2 duration, except for the first The transmission duration of other subframes other than the subframe is reduced by the T2 duration, as shown in the shaded part in FIG. 3 , and the shaded part is the duration vacated by shortening the CP.

Assume that the current moment is subframe #n+1, terminal 1 is transmitting uplink data, and in the next subframe #n+2, terminal 2 needs to transmit uplink data. That is, there is an upload start time corresponding to terminal 2 in the time period corresponding to the next subframe #n+2 of subframe #n+1 of the data frame currently being transmitted. In this case, terminal 2 is in the subframe #n+1 performs a clear channel assessment (CCA, Channel Clear Assessment) detection on the channel during the T2 period vacated, because at this time it will not be interfered by terminal 1, and in the absence of interference from other sources of interference, the clear channel assessment The detection can pass, and the terminal 2 can perform uplink data transmission, which increases the probability of the terminal 2 performing uplink data transmission. In addition, the terminal 2 can also determine the data frame to be transmitted by itself within the T2 duration vacated by the subframe #n+1 and the T1 duration vacated by the subframe #n+2. Determining the data frame to be transmitted by itself may include preparing for the transmission of the data frame, which is a prior art, and will not be repeated here.

The terminal 2 transmits the determined data frame to be transmitted according to the uploading data frequency of the terminal 2 uploading the data frame included in the authorization license for the terminal 2 after the T1 duration vacated by the subframe #n+2.

In practical applications, the design criterion of the CP in the LTE system is to be greater than the maximum multipath delay in the propagation environment. After comparison, it is found that the CP length in the LTE system is an order of magnitude larger than that in WLAN. This is because LTE has to consider the application of outdoor macro cells, while WLAN only considers hotspot coverage. The CP of 0.4 microseconds in the LTE system can already support 800* 10^(-9)*3*10^8=240 meters of multipath transmission path difference, which is far greater than the possible multipath path difference in the actual indoor propagation environment, so IEEE further proposes to shorten the CP to 0.4 microseconds, Its corresponding multi-path path difference of 120 meters is still sufficient in most indoor scenes. That is to say, only 0.4 microseconds in the normal CP in the LTE system is necessary. Therefore, it is entirely possible to free up the duration of T1 and/or T2 by shortening the CP.

It should be noted that, the foregoing description using the terminal 1 and the terminal 2 as examples is only a specific example of the present invention, and does not constitute a limitation of the present invention.

Applying the embodiment shown in Figure 1 of the present invention, the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted uplink data and the last cyclic prefix of the subframe currently being transmitted The cyclic prefix of the OFDM symbol is shortened, so that the terminal currently transmitting uplink data is prevented from interfering with other terminals in idle channel assessment and detection during the time corresponding to the shortened cyclic prefix, and when there are no other In the case of interference from interference sources, other terminals can perform uplink data transmission without waiting for the subframe pre-configured by the base station to perform channel state detection, thereby reducing delay and improving scheduling flexibility. At the same time, multiple terminals can Uplink data transmission is performed at the same time, which reduces the waste of channel resources and improves the utilization rate of channel resources. In addition, through RRC static configuration, the interaction between the base station and the terminal is simple and easy to implement.

FIG. 2 is a schematic flowchart of a second multi-terminal uplink scheduling method provided by an embodiment of the present invention, which may include:

S201: The base station judges that there is an upload start time in the time period corresponding to the next subframe of the subframe of the currently transmitting data frame according to the start upload time of each terminal, and determines x number of uplink data transmissions currently in progress The terminal and the y terminals to be uplink data transmission, the y terminals are the terminals corresponding to the upload start time existing in the time period corresponding to the next subframe of the subframe of the currently transmitting data frame.

S202: The base station sends a second scheduling instruction to each of the x terminals through a dynamic uplink grant method, and the second scheduling instruction includes shortening the last OFDM of the subframe that the terminal is currently transmitting. Information with symbolic cyclic prefixes.

Specifically, the foregoing dynamic uplink grant manner may be a dynamic configuration manner of UL (UpLink) grant.

S203: The base station sends a third scheduling instruction to each of the y terminals through a dynamic uplink grant method, and the third scheduling instruction includes shortening the first regular number of the first subframe of the data frame to be transmitted by the terminal. Cyclic prefix information of the cross frequency division multiplexed symbol.

S204: Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the transmission duration of the subframe Reduce T3 duration.

Wherein, the T3 duration is greater than the preset third duration. Specifically, the preset third duration may be 4 microseconds.

S205: Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that the subframe The frame transmission duration is reduced by T4 duration.

Wherein, the sum of the T3 duration and the T4 duration is greater than a preset fourth duration. Specifically, the fourth preset duration may be 9 microseconds.

S206: Each of the y terminals performs idle channel assessment detection on the channel within the time duration T3 and T4, and determines the data frame to be transmitted by itself.

S207: Each of the y terminals transmits the determined data frame to be transmitted according to the uploading data frequency of the terminal's uploading data frame included in the authorization license.

As shown in FIG. 4 , it is assumed that the start uploading time of the self-uploaded data frame determined by terminal 1 is subframe #n+1, and the start uploading time of self-uploaded data frame determined by terminal 2 is subframe #n+2.

Assuming that the current moment is subframe #n+1, terminal 1 is transmitting uplink data, and in the next subframe #n+2, terminal 2 needs to transmit uplink data. The base station judges the next subframe #n of the subframe #n+1 of the data frame currently being transmitted according to the subframe #n+1 of the upload start time of terminal 1 and the subframe #n+2 of the upload start time of terminal 2 In the time period corresponding to +2, there is an upload start time of terminal 2, and x terminals currently transmitting uplink data and y terminals waiting to transmit uplink data are determined. To simplify the description, in this embodiment, assuming that both x and y are 1, the terminal currently transmitting uplink data is only terminal 1, and there is Terminal 2 is the only terminal corresponding to the start uploading time of .

The base station sends the second scheduling instruction to the terminal 1 through the dynamic configuration mode of the UL grant, and the second scheduling instruction includes the information of shortening the CP of the last OFDM symbol of the subframe that the terminal 1 is currently transmitting.

The base station sends the third scheduling instruction to the terminal 2 through the dynamic configuration mode of the UL grant, and the third scheduling instruction includes shortening the information of the CP of the first OFDM symbol of the first subframe of the data frame to be transmitted by the terminal 2.

According to the second scheduling instruction, terminal 1 shortens the CP of the last OFDM symbol in the subframe (subframe #n+1) of the data frame it is currently transmitting, so that the transmission duration of terminal 1 in subframe #n+1 is reduced by T3 duration.

According to the third scheduling instruction, the terminal 2 shortens the CP of the first OFDM symbol in the first subframe of the data frame to be transmitted, so that the transmission duration of the terminal 2 in the subframe #n+2 is reduced by T4.

As shown in the shaded part in Figure 4, the shaded part is the duration vacated by shortening the CP. Therefore, terminal 2 performs CCA detection on the channel within the vacant T3 duration, and will not be interfered by terminal 1, and in the absence of interference from other interference sources, CCA detection can pass, and terminal 2 can perform uplink data transmission , which increases the probability that terminal 2 performs uplink data transmission. In addition, the terminal 2 can also determine the data frame to be transmitted by itself within the vacant time length of T3 and T4, and the determination of the data frame to be transmitted by itself can include the preparation work for transmitting the data frame, which is a prior art. I won't go into details here.

After the vacant duration of T3 and T4, the terminal 2 transmits the determined data frame to be transmitted according to the upload data frequency of the terminal 2 uploading data frames included in the authorization license for the terminal 2.

In practical applications, the design criterion of the CP in the LTE system is to be greater than the maximum multipath delay in the propagation environment. After comparison, it is found that the CP length in the LTE system is an order of magnitude larger than that in WLAN. This is because LTE has to consider the application of outdoor macro cells, while WLAN only considers hotspot coverage. The CP of 0.4 microseconds in the LTE system can already support 800* 10^(-9)*3*10^8=240 meters of multipath transmission path difference, which is far greater than the possible multipath path difference in the actual indoor propagation environment, so IEEE further proposes to shorten the CP to 0.4 microseconds, Its corresponding multi-path path difference of 120 meters is still sufficient in most indoor scenes. That is to say, only 0.4 microseconds in the normal CP in the LTE system is necessary. Therefore, it is entirely possible to free up the duration of T3 and/or T4 by shortening the CP.

It should be noted that, the foregoing description is made by taking both x and y as 1, terminal 1 and terminal 2 as an example, which is only a specific example of the present invention, and does not constitute a limitation of the present invention.

Applying the embodiment shown in Figure 2 of the present invention, the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted uplink data and the last cyclic prefix of the subframe currently being transmitted The cyclic prefix of the OFDM symbol is shortened, so that the terminal currently transmitting uplink data is prevented from interfering with other terminals in idle channel assessment and detection during the time corresponding to the shortened cyclic prefix, and when there are no other In the case of interference from interference sources, other terminals can perform uplink data transmission without waiting for the subframe pre-configured by the base station to perform channel state detection, thereby reducing delay and improving scheduling flexibility. At the same time, multiple terminals can Uplink data transmission is performed at the same time, which reduces the waste of channel resources and improves the utilization rate of channel resources. In addition, through the dynamic configuration of UL grant, the base station notifies the terminal to shorten the CP only when necessary, which reduces the risk of the channel being occupied by other systems.

Corresponding to the foregoing method embodiments, the embodiments of the present invention further provide a network system for assisting access based on permission.

Fig. 5 is a schematic structural diagram of a permission-based assisted access network system provided by an embodiment of the present invention, which may include:

N terminals and a base station, wherein the N terminals are respectively terminal 1, terminal 2, terminal 3...terminal N, and the N terminals share a channel for data communication with the base station.

The base station sends an authorization license for uploading data frames to each of the N terminals in advance, and the authorization license includes an upload data frequency of the terminal uploading data frames;

Each of the N terminals obtains the authorization for uploading data frames sent by the base station for its own terminal, and determines the uploading time of its own data frame according to the received authorization.

In an embodiment shown in FIG. 5 , the base station sends a first scheduling instruction to each of the N terminals through a radio resource control protocol, and the first scheduling instruction includes shortening the number of uplinks to be performed by the terminal. Information about the cyclic prefix of the first OFDM symbol in the first subframe of the data transmission frame and the cyclic prefix of the last OFDM symbol in all subframes;

The first terminal that receives the first scheduling instruction sent by the base station, according to the first scheduling instruction, shortens the first orthogonal frequency division of the first subframe of the data frame to be transmitted by its own terminal to perform uplink data transmission. Multiplexing the cyclic prefix of the symbol, so that the transmission duration of the first subframe is reduced by T1 duration;

According to the first scheduling instruction, the first terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by its own terminal, so that the first The transmission duration of subframes is reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration, wherein the T2 duration is greater than the preset first duration, and the T1 duration is the same as The sum of the T2 durations is greater than the preset second duration;

When there is an upload start time corresponding to the first terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shorten the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted and Within the duration of T1 corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted shortened by the first terminal, the first terminal performs Idle channel assessment and detection, and determine the data frame to be transmitted;

The first terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the first terminal upload data frame included in the authorization.

Specifically, the preset first duration may be 4 microseconds, and the second preset duration may be 9 microseconds.

In another embodiment shown in FIG. 5 , the base station determines that there is an upload start time in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted according to the start upload time of each terminal. When , determine x terminals that are currently transmitting uplink data and y terminals that are to be transmitted uplink data, and the y terminals are present in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted The terminal corresponding to the upload start time;

The base station sends a second scheduling instruction to each of the x terminals in a dynamic uplink grant manner, and the second scheduling instruction includes shortening the last orthogonal frequency of the subframe that the terminal is currently transmitting. information on the cyclic prefix of the demultiplexed symbols;

The base station sends a third scheduling instruction to each of the y terminals in a dynamic uplink grant mode, and the third scheduling instruction includes shortening the first subframe of the data frame to be transmitted by the terminal Information about the cyclic prefix of the first OFDM symbol;

Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the subframe The transmission duration is reduced by T3 duration, wherein the T3 duration is greater than the preset third duration;

Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that The transmission duration of the subframe is reduced by T4 duration, wherein the sum of the T3 duration and the T4 duration is greater than a preset fourth duration;

Each of the y terminals performs idle channel assessment detection on the channel within the T3 time period and the T4 time period, and determines its own data frame to be transmitted;

Each of the y terminals transmits the determined data frame to be transmitted by itself according to the data upload frequency of the terminal uploading the data frame included in the authorization.

Specifically, the preset third duration may be 4 microseconds, and the fourth preset duration may be 9 microseconds.

Applying the embodiment shown in Figure 5 of the present invention, the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted uplink data and the last cyclic prefix of the subframe currently being transmitted The cyclic prefix of the OFDM symbol is shortened, so that the terminal currently transmitting uplink data is prevented from interfering with other terminals in idle channel assessment and detection during the time corresponding to the shortened cyclic prefix, and when there are no other In the case of interference from interference sources, other terminals can perform uplink data transmission without waiting for the subframe pre-configured by the base station to perform channel state detection, thereby reducing delay and improving scheduling flexibility. At the same time, multiple terminals can Uplink data transmission is performed at the same time, which reduces the waste of channel resources and improves the utilization rate of channel resources. When the CP is shortened by RRC static configuration, the interaction between the base station and the terminal is simple and easy to implement; when the CP is shortened by the dynamic configuration of UL grant, the base station notifies the terminal to carry out the CP only when necessary. The shortening of CP reduces the risk that the channel is occupied by other systems.

It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. any such actual relationship or order exists between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Each embodiment in this specification is described in a related manner, the same and similar parts of each embodiment can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for relevant parts, refer to part of the description of the method embodiment.

Those of ordinary skill in the art can understand that all or part of the steps in the implementation of the above method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, referred to herein as Storage media, such as: ROM/RAM, disk, CD, etc.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present invention are included in the protection scope of the present invention.

Claims (4)

1. A multi-terminal uplink scheduling method, characterized in that it is applied to a network system based on permission-assisted access, and the network system includes N terminals and a base station, wherein the N terminals share a channel with the base station For data communication, each of the N terminals obtains in advance an authorization from the base station for uploading data frames of the terminal, the authorization includes the upload data frequency of the terminal to upload data frames, and the N terminals Each terminal in the system determines the start uploading time of its own uploaded data frame according to the received authorization license; The methods include: After each of the N terminals establishes a data communication connection with the base station, the base station sends a first scheduling instruction to the terminal through a radio resource control protocol, and the first scheduling instruction includes shortening the waiting period of the terminal. Information about the cyclic prefix of the first OFDM symbol in the first subframe of the data frame for uplink data transmission and the cyclic prefix of the last OFDM symbol in all subframes ; According to the first scheduling instruction, the terminal shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted by the terminal, so that the The transmission duration of the first subframe is reduced by T1 duration; According to the first scheduling instruction, the terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by the terminal, so that the first The transmission duration of the subframe is further reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration, wherein the T2 duration is greater than the preset first duration, and the T1 duration is the same as the T1 duration The sum of the above T2 durations is greater than the preset second duration; When there is an upload start time corresponding to the terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shortening the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted is equal to that of the terminal Within the duration of T1 corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted, the terminal performs idle channel assessment detection on the channel, and determines that it is waiting for transmitted data frames; The terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the terminal upload data frame included in the authorization license. 2. A multi-terminal uplink scheduling method, characterized in that it is applied to a network based on grant-assisted access technology, and the network includes N terminals and a base station, wherein the N terminals share a channel with the base station For data communication, each of the N terminals obtains in advance an authorization from the base station for uploading data frames of the terminal, and the authorization includes the upload data frequency of the terminal to upload data frames, among the N terminals Each terminal of the system determines the start uploading time of its own uploaded data frame according to the received authorization license; The methods include: When the base station determines that there is an upload start time in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted according to the start upload time of each terminal, determine the x number of data frames currently being transmitted. A terminal and y terminals to be used for uplink data transmission, wherein the y terminals are terminals corresponding to the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted; The base station sends a second scheduling instruction to each of the x terminals in a dynamic uplink grant manner, and the second scheduling instruction includes shortening the last orthogonal frequency of the subframe that the terminal is currently transmitting. information on the cyclic prefix of the demultiplexed symbols; The base station sends a third scheduling instruction to each of the y terminals in a dynamic uplink grant mode, and the third scheduling instruction includes shortening the first subframe of the data frame to be transmitted by the terminal Information about the cyclic prefix of the first OFDM symbol; Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the subframe The transmission duration is reduced by T3 duration, wherein the T3 duration is greater than the preset third duration; Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that The transmission duration of the subframe is reduced by T4 duration, wherein the sum of the T3 duration and the T4 duration is greater than a preset fourth duration; Each of the y terminals performs idle channel assessment detection on the channel within the T3 time period and the T4 time period, and determines its own data frame to be transmitted; Each of the y terminals transmits its own determined data frame to be transmitted according to the data upload frequency of the terminal uploading data frame included in the authorization license. 3. A network system based on permission-assisted access, characterized in that it comprises: N terminals and a base station, wherein the N terminals share a channel for data communication with the base station; The base station sends an authorization license for uploading data frames to each of the N terminals in advance, and the authorization license includes an upload data frequency of the terminal uploading data frames; Each terminal in the N terminals obtains the authorization license sent by the base station for uploading data frames by its own terminal, and determines the start uploading time of its own upload data frame according to the received authorization license; The base station sends a first scheduling instruction to each of the N terminals through a radio resource control protocol, and the first scheduling instruction includes shortening the first subframe of a data frame to be transmitted by the terminal for uplink data transmission Information about the cyclic prefix of the first OFDM symbol and the cyclic prefix of the last OFDM symbol of all subframes; The first terminal that receives the first scheduling instruction sent by the base station, according to the first scheduling instruction, shortens the first orthogonal frequency division of the first subframe of the data frame to be transmitted by its own terminal to perform uplink data transmission. Multiplexing the cyclic prefix of the symbol, so that the transmission duration of the first subframe is reduced by T1 duration; According to the first scheduling instruction, the first terminal shortens the cyclic prefix of the last OFDM symbol in all subframes of the data frame to be transmitted by its own terminal, so that the first The transmission duration of subframes is reduced by T2 duration, and the transmission duration of other subframes except the first subframe is reduced by T2 duration, wherein the T2 duration is greater than the preset first duration, and the T1 duration is the same as The sum of the T2 durations is greater than the preset second duration; When there is an upload start time corresponding to the first terminal in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted, shorten the T2 duration corresponding to the cyclic prefix of the subframe currently being transmitted and Within the duration of T1 corresponding to the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted shortened by the first terminal, the first terminal performs Idle channel assessment and detection, and determine the data frame to be transmitted; The first terminal transmits the determined data frame to be transmitted by itself according to the upload data frequency of the first terminal upload data frame included in the authorization. 4. A network system based on permission-assisted access, characterized in that it comprises: N terminals and a base station, wherein the N terminals share a channel for data communication with the base station; The base station sends an authorization license for uploading data frames to each of the N terminals in advance, and the authorization license includes an upload data frequency of the terminal uploading data frames; Each terminal in the N terminals obtains the authorization license sent by the base station for uploading data frames by its own terminal, and determines the start uploading time of its own upload data frame according to the received authorization license; When the base station determines that there is an upload start time in the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted according to the start upload time of each terminal, determine the x number of data frames currently being transmitted. A terminal and y terminals to be used for uplink data transmission, wherein the y terminals are terminals corresponding to the time period corresponding to the next subframe of the subframe of the data frame currently being transmitted; The base station sends a second scheduling instruction to each of the x terminals in a dynamic uplink grant manner, and the second scheduling instruction includes shortening the last orthogonal frequency of the subframe that the terminal is currently transmitting. information on the cyclic prefix of the demultiplexed symbols; The base station sends a third scheduling instruction to each of the y terminals in a dynamic uplink grant mode, and the third scheduling instruction includes shortening the first subframe of the data frame to be transmitted by the terminal Information about the cyclic prefix of the first OFDM symbol; Each of the x terminals, according to the second scheduling instruction, shortens the cyclic prefix of the last OFDM symbol in the subframe of the data frame currently transmitted by itself, so that the subframe of the subframe The transmission duration is reduced by T3 duration, wherein the T3 duration is greater than the preset third duration; Each of the y terminals shortens the cyclic prefix of the first OFDM symbol in the first subframe of the data frame to be transmitted according to the third scheduling instruction, so that The transmission duration of the subframe is reduced by T4 duration, wherein the sum of the T3 duration and the T4 duration is greater than a preset fourth duration; Each of the y terminals performs idle channel assessment detection on the channel within the T3 time period and the T4 time period, and determines its own data frame to be transmitted; Each of the y terminals transmits the determined data frame to be transmitted by itself according to the data upload frequency of the terminal uploading the data frame included in the authorization.