KR101846976B1 - Multiple uplink-timing operating apparatus and operating method - Google Patents

Abstract

The present invention discloses a technology for setting (ensuring) sufficiently long GP in an LTE-TDD system to support larger cell radius, and allocating more resources to a downlink to improve a downlink transmission rate, through realizing a new technology for operating (synchronizing) two or more uplink transmission timings, which are multiple uplink transmission timings, on a terminal.

Description

[0001] MULTIPLE UPLINK-TIMING OPERATING APPARATUS AND OPERATING METHOD [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a technique for operating uplink transmission timing, and more particularly, to a base station operating (synchronizing) two or more uplink transmission timings, i.e., multiple uplink transmission timings, And to improve the downlink transmission rate.

1 shows a general frame structure of LTE-TDD. The LTE-TDD frame has a length of 10 ms, and each frame is composed of a half frame of 5 ms. Each half-frame consists of five sub-frames, and each sub-frame has a length of 1 ms. When a normal cyclic prefix (CP) is supported, each subframe is composed of 14 OFDM symbols.

In the LTE-TDD frame, there are seven types (configuration 0 to 6) DL / UL resource allocation structures having a 5 ms or 10 ms switching point period. In the case of configuration 1, as shown in FIG. 1 , A UL subframe U, a UL subframe U, and a DL subframe D in a 5 ms switching point period (half frame), a DL subframe D, a special subframe S, a UL subframe U, .

Here, the special subframe S internally includes a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS).

In the LTE-TDD, the structure of the special subframe S is defined as nine types (Format 0 to 8) according to the number of symbols constituting each of DwPTS, GP and UpPTS.

The DwPTS is used for downlink data transmission and may therefore be viewed as part of a DL subframe. The DwPTS can be configured from a minimum of 3 symbols to a maximum of 12 symbols.

UpPTS can be used for SRS (sounding reference signal) and random access for UL. The UpPTS may be composed of one or two symbols.

The GP is used to secure a guard period necessary for switching (changing) between the downlink and the uplink in the LTE-TDD frame, and should be set long enough to take account of propagation delay in the cell.

That is, the GP is closely related to the size of the LTE-TDD cell, and the longer the GP, the larger the cell can be supported. This GP is composed of the remaining symbols for which the DwPTS and the UpPTS are not set in the special subframe (S).

For example, in the case of Format 4, as shown in FIG. 1, the GP is set to one symbol except 12 symbols for which DwPTS is set in the special subframe S and one symbol for which UpPTS is set.

In order to support a larger cell radius in the LTE-TDD system, it is necessary to set the length of the GP in the special sub-frame S to be long as described above. However, if the GP is set to be long, most of the limited OFDM symbols (for example, 14) of the special subframe (S) must be configured by the GP.

However, on the data traffic characteristics of mobile communication services, downlink data transmission speed is more important than uplink data transmission speed. Therefore, in the frame structure of the LTE-TDD system, if the downlink transmission rate is increased by increasing the DwPTS utilization of the special subframe S, the system performance can be further increased.

However, in order to support a large cell in the frame structure of the current LTE-TDD system, the downlink transmission rate is lowered because the weight of the DwPTS of the special subframe S is lowered and the GP is increased to set the GP longer.

Accordingly, the present invention proposes a technique capable of improving the downlink transmission rate by allocating more resources to the downlink while supporting a larger cell radius by setting (securing) the GP in the LTE-TDD system sufficiently do.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technology for supporting a larger cell radius and improving a downlink transmission rate in an LTE-TDD system.

According to a first aspect of the present invention, there is provided an apparatus for operating multiple uplink timings comprising: a terminal group classifying unit for classifying a plurality of terminals into at least two terminal groups; A plurality of uplink synchronization units for performing synchronization to have different uplink transmission timings from each other in each terminal group; For each terminal group, the number of symbols used for uplink transmission in an uplink sub-frame of synchronized uplink transmission timing is reduced by a specific number to shorten an uplink transmission time by a time corresponding to the specific number, And allocates uplink resources such that time is used as a guard period for downlink / uplink change.

Preferably, the two or more terminal groups include a second terminal group synchronized with a second uplink transmission timing that is slower than a reference uplink transmission timing by a specific time, and a second terminal group synchronized with the second terminal group by a predetermined number of symbols And a first terminal group that is synchronized with the uplink transmission timing.

Advantageously, said specific time may be a time obtained by subtracting the UL to DL switching time required for uplink / downlink switching in said specified number of symbol times, or in said specified number of symbol times.

Preferably, the multiple uplink synchronization unit is configured to perform uplink transmission timing synchronization (RMA) on the basis of a timing command (Timing Advance) transmitted through Random Access with a UE or a MAC (Medium Access Control-CE) Can be performed.

Preferably, the control unit controls the first and second terminal groups so that the last certain number of symbols in the uplink sub-frame of the first and second uplink transmission timings synchronized with each other are not used for uplink transmission Can be set.

Preferably, the controller sets a last certain number of symbols in the uplink subframe to SRS (Sounding Reference Signal) transmission only, while setting the SRS transmission period to be as long as possible within a predetermined allowable range, The last certain number of symbols in the subframe can be prevented from being used for uplink transmission except when the SRS transmission period arrives.

Preferably, when the SRS transmission period set in the specific terminal group of either the first or second terminal group arrives, the control unit sets the last symbol in the uplink subframe at the time when the SRS transmission period arrives to SRS It is possible to allocate uplink resources to be used for transmission and set up the uplink subframes of other terminal groups that overlap with symbols transmitting SRS in the specific terminal group to not be used for uplink transmission.

Preferably, a frame of a structure including at least two uplink sub-frames between a special sub-frame having a guard time (GP) symbol and a downlink sub-frame is used, Allocating an uplink resource to use the last uplink subframe of at least two of the uplink subframes following the second uplink transmission timing in the frame for uplink transmission and to use uplink resources for uplink transmission in the last uplink subframe And the downlink subframe may be matched for the specific time.

Preferably, the control unit controls the uplink subframe of the immediately preceding one of the two or more uplink subframes corresponding to the first uplink transmission timing in the frame to be used for the uplink transmission for the first terminal group Link resources are allocated so that a symbol not used for uplink transmission in the immediately preceding uplink subframe and a last uplink subframe used by the second terminal group can be matched by the predetermined number of symbols.

Preferably, the control unit sets an uplink symbol after a protection time (GP) symbol in the special subframe so that it is not used for uplink transmission, and notifies the first terminal group of the special subframe guard time GP) symbol to a symbol immediately before an uplink sub-frame used for uplink transmission is used as a guard time (GP), and for the second terminal group, a guard time (GP) symbol in a special sub- The time up to the symbol immediately before the uplink sub-frame used for transmission can be used as the guard time GP.

Preferably, the control unit sets an uplink symbol after the guard time (GP) symbol in the special subframe to be dedicated to SRS transmission, so that the uplink symbol after the guard time (GP) symbol in the special subframe is up It can be prevented from being used for link transmission.

Preferably, the controller is further configured to determine, for each of the first and second terminal groups, an uplink subframe location used by the terminal group for uplink transmission in the frame, a minimum response waiting time for downlink transmission, Frame for a downlink sub-frame and a sub-frame for use in downlink transmission in a downlink sub-frame and a special sub-frame in the frame based on the minimum response waiting time, and for each of the first and second terminal groups, And allocate downlink resources to use the determined subframe among the special subframes for downlink transmission.

In order to achieve the above object, a multiple uplink timing operation method performed by a base station according to a second aspect of the present invention performs synchronization so as to have different uplink transmission timings for different terminal groups for two or more terminal groups Multiple uplink synchronization steps; And shortening the number of symbols used for uplink transmission in an uplink subframe of each synchronized uplink transmission timing by a specific number for each terminal group to shorten the uplink transmission time by a time corresponding to the specific number, And allocating the uplink resources such that the allocated time is used as a Guard Period for downlink / uplink change.

Preferably, the two or more terminal groups include a second terminal group synchronized with a second uplink transmission timing that is slower than a reference uplink transmission timing by a specific time, and a second terminal group synchronized with the second terminal group by a predetermined number of symbols And a first terminal group that is synchronized with the uplink transmission timing.

Advantageously, the scheduling step comprises, for the first and second terminal groups, the last certain number of symbols in the uplink sub-frame of the first and second uplink transmission timings, respectively, And a second setting step of setting the first setting step.

Preferably, in the first setting step, the last certain number of symbols in the uplink subframe are set to SRS (Sounding Reference Signal) dedicated transmission, but the SRS transmission period is set as long as possible within a predefined tolerance, The last certain number of symbols in the uplink subframe can be prevented from being used for uplink transmission except when the SRS transmission period arrives.

Preferably, when the SRS transmission period set in the specific terminal group of the first and second terminal groups arrives, the last symbol in the uplink subframe at the time when the SRS transmission period arrives is used for SRS transmission Allocating uplink resources and setting up the uplink subframes of the other terminal groups overlapping with the symbols transmitting the SRS in the specific terminal group to not be used for the uplink transmission.

Preferably, a frame of a structure including at least two uplink sub-frames between a special sub-frame having a guard time (GP) symbol and a downlink sub-frame is used, , Allocating uplink resources to use the last uplink subframe of two or more uplink subframes following the second uplink transmission timing in the frame for uplink transmission, and allocating uplink resources for uplink transmission in the last uplink subframe The unused symbol and the downlink subframe may be matched by the specific time.

Advantageously, the scheduling step comprises: for the first terminal group, to use uplink subframes immediately before the last of the two or more uplink subframes following the first uplink transmission timing in the frame for uplink transmission The uplink resources may be allocated such that the symbols not used for uplink transmission in the immediately preceding uplink subframe and the last uplink subframe used by the second terminal group are matched by the predetermined number of symbols.

Advantageously, the scheduling step includes a second setting step of setting uplink symbols after guard time (GP) symbols in the special subframe not to be used for uplink transmission, The time from the protection time (GP) symbol in the special subframe to the symbol immediately before the uplink subframe used in the uplink transmission is used as the protection time (GP), and the protection in the special subframe The time from the time (GP) symbol to the symbol immediately before the uplink sub-frame used for uplink transmission can be used as the guard time (GP).

According to the multi-uplink timing operating apparatus and the multi-uplink timing operating method of the present invention, a new technology for operating (synchronizing) two or more uplink transmission timings, i.e., multiple uplink transmission timings, In the TDD system, the GP is set long enough (secured) to support a larger cell radius, and more resources are allocated to the downlink, thereby improving the downlink transmission rate.

1 is an exemplary diagram showing a general frame structure of LTE-TDD.
2 is an exemplary diagram showing a communication system environment to which the present invention is applied.
3 is a block diagram illustrating the configuration of a multiple uplink timing operating apparatus (base station) according to a preferred embodiment of the present invention.
4 is an exemplary diagram illustrating a frame structure according to the multi-uplink timing operation technique proposed by the present invention.
5 is a diagram illustrating an example of a downlink / uplink minimum response waiting time for reference to downlink resource allocation for each terminal group in the present invention.
6 is an exemplary diagram illustrating an example of downlink / uplink resource allocation for each terminal group in a frame structure according to the multiple uplink timing operating technique proposed by the present invention.
FIG. 7 is a flowchart illustrating a control flow of a multi-uplink timing operation method according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

2 is an exemplary diagram showing a communication system environment to which the present invention is applied.

As shown in FIG. 2, the present invention provides a mobile communication system including a base station (BS) 100, a terminal (BS) 100, a base station 100, , 3, 4, 5, ...), that is, a mobile communication system.

In the communication system to which the present invention is applied, the downlink data transmission rate is more important than the uplink data transmission speed in the data traffic characteristic of the mobile communication service.

The communication system to which the present invention is applied uses an LTE-TDD communication scheme.

The LTE-TDD frame has a structure including a DL sub-frame and a UL sub-frame internally including a special sub-frame S composed of DwPTS, GP, and UpPTS.

Therefore, in the communication system (LTE-TDD system) to which the present invention is applied, if the downlink transmission rate is increased by increasing the utilization of the DwPTS of the special subframe S in the LTE-TDD frame structure, There will be.

On the other hand, the GP of the special sub-frame S is used to secure a guard period necessary for switching (changing) between the downlink and the uplink in the LTE-TDD frame.

The length of such a GP can be determined by various factors, and it should be set long enough to take into account propagation delays in the cell.

The reason for this is that a terminal located at a cell boundary is located at a position closer to the base station 100 than the terminal located close to the base station 100 so that a plurality of terminals 1, 2, 3, 4, 5, You need to start the transfer first. However, the UE at the cell boundary can not transmit data in the uplink until it completely receives the signal transmitted in the downlink.

Therefore, the GP not only secures the guard time required for DL-to-UL conversion in the terminal but also compensates for the round trip delay time (or radio propagation delay) in the cell.

Therefore, since the GP plays a role of securing the guard time and compensating the propagation delay time (or radio propagation delay) in the cell, it is possible to support a larger cell by setting GP sufficiently long.

In order to support a large cell in the frame structure of the existing LTE-TDD, it is necessary to lower the weight of the DwPTS of the special sub-frame (S) and to increase the GP weight to increase the GP, and in this case, the downlink transmission speed is lowered.

Accordingly, the present invention proposes a technique capable of improving the downlink transmission rate by allocating more resources to the downlink while supporting a larger cell radius by setting (securing) the GP in the LTE-TDD system sufficiently do.

More specifically, the present invention realizes a new technique (hereinafter, referred to as multiple uplink transmission timing operation method) for operating (synchronizing) two or more uplink transmission timings, i.e., multiple uplink transmission timings, In the TDD system, the GP is set long enough (secured) to support a larger cell radius, while allocating more resources to the downlink to improve the downlink transmission rate.

Hereinafter, a multiple uplink timing operation apparatus according to a preferred embodiment of the present invention will be described in more detail with reference to FIG.

That is, the multiple uplink timing operating apparatus of the present invention realizes the multi-uplink transmission timing operation scheme (technique) proposed in the present invention, and may correspond to the base station 100 in the communication system environment of FIG. 3 .

Therefore, for convenience of description, the multi-uplink timing operation apparatus of the present invention will be described with reference to the reference numeral of the base station 100. [

In addition, for convenience of explanation, a resource allocation structure (hereinafter, referred to as a resource allocation structure) including two or more uplink subframes (UL) between a special subframe S having a guard time (GP) symbol and a downlink subframe DL (configuration 1) is used, and the special sub-frame S at this time will be described by taking the case of Format 4 as an example.

3, the multiple uplink timing operating apparatus 100 according to the present invention includes a plurality of uplink terminal groups 1, 2, 3, 4, 5, A plurality of uplink synchronization units (120) for performing synchronization so as to have different uplink transmission timings from the other terminal groups, for each terminal group, The number of symbols used for uplink transmission in the uplink sub-frame of the transmission timing is reduced by a specified number to shorten the uplink transmission time by the time according to the specific number, and the reduced time is used for protection for downlink / And allocates uplink resources to be used as a guard period.

The terminal group classifying unit 110 includes a plurality of terminals 1 and 2 located in a plurality of terminals, i.e., cells of the base station 100 and using mobile communication services based on the uplink / downlink transmission with the base station 100 , 3, 4, 5, ...) are divided into two or more terminal groups.

At this time, in the present invention, there is no limitation on a method of dividing a plurality of terminals into terminal groups.

However, it is preferable that the terminal located at the cell boundary of the base station 100 belongs to a terminal group having a longer guard time (GP) based on a guard time (GP) used for each terminal group.

The terminal group classification time point is preferably a time point when the terminal first accesses the base station 100. [

Hereinafter, for the convenience of description, it is assumed that two terminal groups (first and second) as two or more terminal groups, terminals 1 and 3 are classified into a first terminal group, The second terminal group is divided into the second terminal group.

The multiple uplink synchronization unit 120 performs synchronization for each terminal group to have different uplink transmission timings from those of the other terminal groups.

That is, the multiple uplink synchronization unit 120 performs synchronization so as to have different uplink transmission timings for each of the first and second terminal groups.

Hereinafter, for convenience of explanation, the second terminal group is synchronized with the second uplink transmission timing, which is slower than the reference uplink transmission timing by a specific time, and the first terminal group is synchronized with the predetermined number of symbols It will be assumed that synchronization is performed at a slow first uplink transmission timing.

More specifically, the multiple uplink synchronization unit 120 may be configured to synchronize the uplink data with the uplink data based on a timing command (Timing Advance) transmitted through a random access (MAC) or a Medium Access Control-Control Element (MAC) And performs uplink transmission timing synchronization.

For example, the multiple uplink synchronization unit 120 may estimate the UL timing error in the random access (RA) process with the terminal 2 by referring to the terminal 2 belonging to the second terminal group, 2 to the second uplink transmission timing (4b in FIG. 4 or 6b in FIG. 6) that is slower than the reference uplink transmission timing by a specific time relative to the uplink transmission timing in the first uplink transmission.

The multiple uplink synchronization unit 120 transmits a random access response (RAR) message including a timing command TA to the terminal 2 during the random access (RA) process with the terminal 2, Link transmission timing synchronization can be performed.

The multi-uplink synchronization unit 120 transmits a timing command TA of the MAC CE, which adaptively adjusts the uplink transmission timing, in a connected mode of the terminal 2 after the random access (RA) 2 to the second uplink transmission timing (4b in FIG. 4 or 6b in FIG. 6) by the timing of the movement of the terminal 2 or the timing command TA during the random access (RA) Can be synchronized.

For example, the multiple uplink synchronization unit 120 can estimate the UL timing error in the random access (RA) process with the terminal 1 by referring to the terminal 1 belonging to the first terminal group, (4a in FIG. 4 or 6a in FIG. 6) slower by a certain number of symbols than the second terminal group (second uplink transmission timing) based on the uplink transmission timing of the first terminal group A timing command (TA) can be formed.

Accordingly, the multiple uplink synchronization unit 120 transmits the RAR message including the timing command TA constructed in the course of the random access (RA) with the terminal 1 to the terminal 1, Synchronization can be performed.

Then, the multiple uplink synchronization unit 120 transmits a timing command (TA) of the MAC CE adaptively adjusting the uplink transmission timing to the terminal 1 in the connection mode of the terminal 1 after the random access (RA) , The uplink transmission timing which can not be compensated by the timing command TA during the movement of the terminal 1 or during the random access (RA) can be synchronized with the first uplink transmission timing (4a in Fig. 4 or 6a in Fig. 6) .

Here, the second terminal group is synchronized by the present invention at a second uplink transmission timing that is slower than the reference uplink transmission timing by a specific time.

The particular time may be a certain number of symbol times or may be a time minus a UL to DL transition time required for uplink / downlink conversions in a certain number of symbol times.

FIG. 4 shows a frame structure according to an embodiment of the present invention when the specific time is a specific number of symbol times. At this time, if the frame structure of the group A shown in FIG. 4 corresponds to the first terminal group, the frame structure of the group B corresponds to the second terminal group.

For example, if a specific number is assumed to be one symbol, a certain number of symbol times will be the time of one symbol (e.g., 71.3542 mu s).

In this case, the second terminal group (Group B) has a second uplink transmission timing (4b, 2071.3542) which is slower than the reference uplink transmission timing (2000 占 퐏) by a specific time (= 1 symbol 71.3542 占 퐏) lt; / RTI >

On the other hand, the first terminal group is synchronized with the first uplink transmission timing which is slow by a certain number of symbols as compared with the second terminal group.

In this case, as shown in FIG. 4, the first terminal group (Group A) has a first uplink transmission timing (4a) slower than the second terminal group 4b by a specific number, that is, one symbol (= specific time 71.3542s) ), In other words, the first uplink transmission timing (4a, 2142.7083 μs), which is slower than the reference uplink transmission timing (2000 μs) by two symbols (= 142.7083 μs).

6 shows a frame structure according to an embodiment of the present invention in a case where a specific time is a time obtained by subtracting a UL to DL switching time required for uplink / downlink switching in a specific number of symbol times. At this time, if the frame system of Group A shown in FIG. 6 corresponds to the first terminal group, the frame system of Group B corresponds to the second terminal group.

For example, if a specific number is assumed to be one symbol, a certain number of symbol times will be the time of one symbol (e.g., 71.3542 mu s). Therefore, the specific time will be the time (51.0417 μs) minus the UL to DL switching time (20.3125 μs) required in the actual communication system environment at one symbol 71.3542 μs.

In this case, the second terminal group (Group B) is synchronized to the second uplink transmission timing (6b, 2051.0417 μs) slower than the reference uplink transmission timing (2000 μs) by a specific time (51.0417 μs) do.

On the other hand, the first terminal group is synchronized with the first uplink transmission timing which is slow by a certain number of symbols as compared with the second terminal group.

In this case, as shown in FIG. 6, the first terminal group (Group A) has the first uplink transmission timing (the first uplink transmission timing) slower than the second terminal group 6b by a specific number, that is, one symbol (= specific time 71.3542s) 6a), in other words, the first uplink transmission timing 6a, 2122.3959s, which is slow as the specific time (51.0417 占 퐏) and one symbol (= 71.3542 占 퐏) compared with the reference uplink transmission timing (2000 占 퐏).

As described above, in the present invention, as a basic configuration for improving the downlink transmission rate by allocating more resources to the downlink while setting (ensuring) the GP sufficiently long to support a larger cell radius, That is, multiple uplink transmission timings are operated (synchronized).

The control unit 130 reduces the number of symbols used for uplink transmission in the uplink subframe UL of the synchronized uplink transmission timing for each terminal group, i.e., the first and second terminal groups, The transmission time is shortened by the time corresponding to the specific number, and the uplink resource is allocated such that the shortened time is used as a guard period for the downlink / uplink change.

That is, in the present invention, an excess time (uplink transmission time reduction time) is created by operating (synchronizing) multiple uplink transmission timings for each terminal group, and this time is used as a guard period.

More specifically, the control unit 130 determines, for the first and second terminal groups, the last specific number (e.g., 1) in the uplink sub-frame (UL) of the first and second uplink transmission timings Are not used for uplink transmission.

That is, the control unit 130 sets, for the first terminal group, that the last one symbol in the uplink sub-frame (UL) of the first uplink transmission timing is not used for uplink transmission. Also, the control unit 130 sets the last one symbol in the uplink sub-frame (UL) of the second uplink transmission timing to not be used for the uplink transmission for the second terminal group.

In the LTE-TDD frame, the last one symbol in the uplink sub-frame (UL) may be used for SRS transmission for UL as well as UpPTS.

The control unit 130 sets the last one symbol in the uplink subframe UL to be dedicated to SRS transmission but sets the SRS transmission period as long as possible within a predetermined allowable range (for example, 320 ms) The last one symbol in the uplink sub-frame (UL) may not be used for uplink transmission other than the point in time when the SRS transmission period arrives.

In this case, since the terminals 1 and 3 belonging to the first terminal group are dedicated to SRS transmission in the last one symbol in the uplink sub-frame (UL) of the first uplink transmission timing synchronized under the control of the base station 100 The last one symbol in the uplink sub-frame (UL) will not be used for uplink transmission, since the SRS will also be transmitted intermittently because it will not transmit uplink data and the SRS transmission period comes at a very long time interval .

In addition, in the last one symbol in the uplink sub-frame (UL) of the second uplink transmission timing synchronized under the control of the base station 100, the terminals 2, 4, 5 belonging to the second terminal group are SRS transmission dedicated Because the SRS will not transmit uplink data and the SRS transmission period arrives at a very long time interval, the SRS will also transmit very intermittently, so that the last one symbol in the uplink subframe (UL) will be.

On the other hand, the situation in which the SRS is transmitted in the terminal group in which the SRS transmission period arrives will be described later in detail.

In addition, the control unit 130 sets uplink symbols, i.e., UpPTS symbols after guard time (GP) symbols in the special subframe S, for the first and second terminal groups, so that they are not used for uplink transmission.

Specifically, the control unit 130 sets the UpPTS symbol to dedicated SRS transmission in the special subframe S so that the UpPTS symbol in the special subframe S is not used for the uplink transmission.

In this case, since the terminals 12, 3, 4, and 5 belonging to the first and second terminal groups do not transmit uplink data because they are dedicated to SRS transmission in the UpPTS symbol in the special subframe S, The UpPTS symbol in the frame S will not be used for uplink transmission.

As described above, according to the present invention, since the last symbol of the UpPTS and the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission cutoff setting) (See FIGS. 4 and 6) of different uplink transmission timings can coexist without overlapping.

According to the present invention, by performing UL scheduling so that only uplink sub-frames (UL) that do not overlap with each other in a terminal group are used for uplink transmission, different uplink transmission timings Frame system (see FIGS. 4 and 6) can coexist without overlapping.

More specifically, the control unit 130 transmits, to the second terminal group, the last uplink sub-frame (UL) of two or more uplink sub-frames (UL) according to the second uplink transmission timing in the frame, And allocates uplink resources for use in transmission so that symbols not used for uplink transmission in the last uplink subframe (UL) and the downlink subframe DL coincide for a specific time.

Referring to FIG. 4, the control unit 130 determines the second uplink transmission timing (4b, 4b) between the special subframe (S) and the downlink subframe (DL) (UL), i.e., the second uplink sub-frame (UL), of the two uplink sub-frames (UL) according to the uplink sub-frame (2071.3542 μs).

In this case, each terminal 2, 4, 5 belonging to the second terminal group (Group B) will transmit the uplink data using the second uplink sub-frame (UL), and the second uplink transmission timing 4b, 2071.3542 the last one symbol of the second uplink subframe UL (14 symbols) is equal to the first one symbol of the downlink subframe DL (DL symbol) Will be matched.

However, according to the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), downlink data is normally transmitted in the downlink sub- Lt; / RTI >

On the other hand, the control unit 130 instructs the first terminal group to transmit the uplink sub-frame (UL) immediately before the last of two or more uplink sub-frames (UL) according to the first uplink transmission timing in the frame And allocates uplink resources so that a symbol not used for uplink transmission in the immediately preceding uplink subframe UL and a last uplink subframe UL used by the second terminal group are matched by a predetermined number of symbols do.

Referring to FIG. 4, the control unit 130 determines the first uplink transmission timing (4a, 4b) between the special subframe (S) and the downlink subframe (DL) for the first terminal group (UL), that is, the first uplink sub-frame (UL), of the two uplink sub-frames (UL) according to the uplink sub-frame (UL-2142.7083 μs).

In this case, each of the terminals 1 and 3 belonging to the first terminal group (Group A) will transmit the uplink data using the first uplink subframe (UL), and the first uplink transmission timing (4a, 2142.7083 μs) (71.3542 mu s) with respect to the second terminal group, the last one symbol of the first uplink subframe UL (14 symbols) is the same as that of the second uplink subframe UL used by the second terminal group It will match the first one symbol.

However, in the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), the second uplink sub- The uplink data may be transmitted.

4, the last one symbol of the second uplink sub-frame UL (14 symbols) used by the second terminal group (Group B) for uplink transmission is the first one of the downlink sub-frames DL The downlink sub-frame DL of the second terminal group (Group B) is continued to the uplink sub-frame (UL).

However, in the actual communication system environment, the UL to DL switching time of the terminal (20.3125 mu s) should be further considered.

This is an embodiment in which the UL to DL switching time (20.3125 mu s) is reflected in the embodiment of FIG. 6, i.e., the second uplink transmission timing of the second terminal group (Group B).

6, the control unit 130 sets the second uplink transmission timing (the first uplink transmission timing) between the special sub-frame S and the downlink sub-frame DL for the second terminal group (Group B) Allocates uplink resources to use the last uplink sub-frame (UL) of the two uplink sub-frames (UL) according to the uplink sub-frame (UL, 6b, 2051.0417 μs) for uplink transmission.

In this case, each terminal 2, 4, 5 belonging to the second terminal group (Group B) will transmit the uplink data using the second uplink sub-frame (UL), and the second uplink transmission timing 6b, 2051.0417 since the last one symbol of the second uplink sub-frame UL (14 symbols) is the same as the first one symbol of the downlink sub-frame (DL) at a specific time 51.0417 mu s).

However, according to the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), the UL downlink switching time (20.3125 mu s) Downlink data can be transmitted in the link sub-frame DL.

As shown in FIG. 6, each of the terminals 1 and 3 belonging to the first terminal group (Group A) will transmit the uplink data using the first uplink sub-frame (UL), and the first uplink transmission timing (14 symbols) of the first uplink subframe (UL) is slower than the second uplink subframe UL (14 symbols) because the first uplink subframe (6a, 2122.3958s) is slower than the second terminal group by one symbol (71.3542s) Lt; RTI ID = 0.0 > UL < / RTI >

However, in the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), the second uplink sub- The uplink data may be transmitted.

In addition, the controller 130 sets uplink symbols, that is, UpPTS symbols after the guard time (GP) symbol in the special subframe S, for the first and second terminal groups, so as not to be used for uplink transmission (Transmission interruption setting).

Accordingly, in the present invention, the uplink transmission time is shortened to the maximum through the transmission blocking setting for the last symbol of the UpPTS and the uplink sub-frame, and the uplink sub-frame use (UL scheduling) And this time is used as a guard period.

4, the time from the GP symbol in the special subframe S to the symbol immediately before the first uplink subframe (UL) used for uplink transmission for the first terminal group (Group A) GP). In other words, it can be seen that the time available for the first terminal group (Group A) to be acquired by the GP is extended up to 285.4166 μs.

4, the time from the GP symbol in the special subframe S to the symbol immediately before the second uplink subframe (UL) used for uplink transmission for the second terminal group (Group B) GP). In other words, in the case of the second terminal group (Group B), it can be seen that the time that can be secured by the GP is extremely long, at most 1000 μs or more.

Therefore, according to the present invention, the long guard time (GP) of the first terminal group (Group A), that is, the protection time (GP) of the terminals 1 and 3 in the first terminal group (Group A) It can be seen that the maximum cell radius that can be supported is determined.

In order to support a large cell in the frame structure of the existing LTE-TDD, it is inevitable to set the guard time (GP) to be long by lowering the weight of the DwPTS of the special subframe S and increasing the weight of the GP. In this case, do.

However, as described above, according to the present invention, by implementing a new technique for operating (synchronizing) multiple uplink transmission timings (hereinafter, referred to as a multi-uplink transmission timing operation scheme), the DwPTS specific weight of the special sub- It is possible to secure a sufficient protection time (GP) for the terminal to be sensed without lowering. Therefore, it is possible to improve the downlink transmission speed by allocating more resources to the downlink while supporting a larger cell radius do.

Hereinafter, a case will be described in which the SRS is transmitted in the terminal group that has arrived at the SRS transmission period.

When the SRS transmission period set in the specific terminal group of either the first terminal group or the second terminal group arrives, the control unit 130 transmits the last symbol in the uplink subframe (UL) at the time when the SRS transmission period arrives to the SRS transmission Lt; RTI ID = 0.0 > uplink < / RTI >

In addition, the controller 130 sets the uplink sub-frame (UL) of another terminal group that overlaps with the symbol for transmitting the SRS in the specific terminal group to not be used for the uplink transmission.

For example, it is assumed that the first terminal group of the first and second terminal groups is a specific terminal group arriving at an established SRS transmission period (for example, 320 ms).

The control unit 130 determines whether the SRS transmission period (for example, 320 ms) set in the first terminal group arrives, the last symbol in the first uplink subframe (UL) used for the uplink transmission at the time when the SRS transmission period arrives Lt; RTI ID = 0.0 > SRS < / RTI >

In this case, the UEs 1 and 3 belonging to the first UE group will transmit SRSs from the last symbol in the first uplink subframe (UL) that transmits the uplink data at the time when the SRS transmission period arrives.

At this time, the controller 130 sets the second uplink sub-frame (UL) of the second terminal group overlapping with the symbol for transmitting the SRS in the first terminal group to not be used for uplink transmission (transmission blocking setting).

This transmission interruption setting can be performed according to the determination of the base station 100, and can be solved when the base station 100 adjusts the UL scheduling for the second terminal group according to the transmission timing of the SRS.

If the SRS is transmitted using some frequency domain, uplink data is transmitted through a second uplink subframe allocated to the second terminal group in a frequency region other than the frequency domain in which the SRS is transmitted in the first terminal group It may be possible.

According to the present invention, since each of the terminals in the first and second terminal groups uses only the limited uplink sub-frame (UL), a downlink sub-frame (DL) is allocated to each terminal group You need to schedule it appropriately.

In this regard, Figure 5 is an exemplary diagram illustrating downlink / uplink minimum response latency (ACK / NACK).

5A shows a waiting time k for receiving a response (ACK / NACK) after the downlink (D) data transmission, assuming an LTE-TDD frame of a configuration 1 structure.

In the LTE-TDD system, the downlink (D) data is transmitted in consideration of the propagation delay and the data processing time between the base station and the terminal, and a response (ACK / NACK) may be included.

However, as shown in FIG. 5A, since the DL / UL resources are dispersed in the LTE-TDD system and thus the fourth subframe may be a downlink instead of an uplink, (ACK / NACK) is received (k = 7) in the eighth sub-frame (third uplink sub-frame) in the same frame and the second sub-frame (K = 6) in which the response (ACK / NACK) for the downlink (D) data transmitted in the 9th subframe (the fourth uplink subframe) It may wait for longer than 4 ms to receive / NACK.

Similarly, FIG. 5B shows a waiting time k for receiving an ACK / NACK response after uplink (U) data transmission assuming an LTE-TDD frame of a configuration 1 structure .

In the LTE-TDD system, in consideration of the propagation delay and the data processing time between the base station and the UE, uplink (U) data is transmitted, and a response (ACK / NACK) may be included.

However, as shown in (b) of FIG. 5, since the DL / UL resources are dispersed in the LTE-TDD system and thus the fourth subframe may be an uplink instead of a downlink, (K = 4) in the seventh sub-frame (second special sub-frame) in the same frame, and a response to the uplink (U) data transmitted in the fourth sub- (K = 6) in which the ACK / NACK is transmitted in the 10th subframe (fourth downlink subframe) in the same frame, the ACK / It may wait for longer than 4 ms for the reception of NACK.

Accordingly, the controller 130 determines, for each of the first and second terminal groups, the uplink subframe location used by the terminal group in the frame for the uplink transmission, the minimum response waiting time for the downlink transmission, and the minimum response time for the uplink transmission Based on the waiting time, a downlink sub-frame in a frame and a sub-frame to be used for downlink transmission among the special sub-frames are determined.

That is, in the case of the first terminal group, the controller 130 controls the uplink subframe position (the first uplink subframe based on half frame) used by the first terminal group for the uplink transmission, (DL) and special sub-frame (DL) based on the minimum response waiting time (after the fourth sub-frame (4ms)) and the minimum response waiting time for the uplink transmission Frame to be used for downlink transmission among frames S is determined.

Also, in the case of the second terminal group, the controller 130 determines whether the uplink subframe location (the second uplink subframe based on half frame) used by the second terminal group for the uplink transmission, (DL) and special sub-frame (DL) based on the minimum response waiting time (after the fourth sub-frame (4ms)) and the minimum response waiting time for the uplink transmission Frame to be used for downlink transmission among frames S is determined.

Accordingly, the control unit 130 determines the minimum response waiting time (after the fourth subframe (4 ms)) for the LTE-TDD frame and the two terminal group operation of the configuration 1 structure and the downlink transmission, Assuming a response wait time (after the fourth sub-frame (4 ms)), as shown in FIGS. 4 and 6, the first and second sub-frames (first downlink sub-frame DL and first (The special sub-frame S), and determine the fifth sub-frame (second downlink sub-frame DL) in the second terminal group (Group B).

In this case, for each of the first and second terminal groups, the control unit 130 determines the first and second sub-frames for the intra-frame downlink sub-frame and the predetermined sub-frame among the special sub-frames, Allocates downlink resources for use in the downlink transmission (first downlink subframe DL and first special subframe S) and allocates downlink resources for the second terminal group (Group B) in the fifth subframe Link sub-frame DL) to be used for downlink transmission, thereby performing DL scheduling.

As described above, the multi-uplink timing operating apparatus (base station) of the present invention realizes a new technology for operating (synchronizing) two or more uplink transmission timings, i.e., multiple uplink transmission timings, In the TDD system, the GP is set long enough (secured) to support a larger cell radius, and more resources can be allocated to the downlink to improve the downlink transmission rate.

Hereinafter, a method of operating multiple uplink timings according to a preferred embodiment of the present invention will be described in detail with reference to FIG.

For convenience of description, reference will be made to base station 100 to be consistent with the preceding description as a multiple uplink timing operating device.

The multiple uplink timing operation method of the base station 100 according to the present invention is a method for operating a multiple uplink timing in a mobile communication system based on uplink / downlink transmission with a base station 100, The plurality of terminals (1, 2, 3, 4, 5, ...) to be used are classified into two or more terminal groups (S100).

Hereinafter, for convenience of explanation, it is assumed that two terminal groups (first and second) as two or more terminal groups, terminals 1 and 3 are classified into a first terminal group, Terminal group is divided into terminal groups.

The multiple uplink timing operation method of the base station 100 according to the present invention performs synchronization so as to have different uplink transmission timings for each of the first and second terminal groups (S110).

At this time, the multi-uplink timing operation method of the base station 100 according to the present invention may include a timing command (Timing Advance) transmitted through a random access (Random Access) or MAC (Medium Access Control-Control Element) , It is possible to perform uplink transmission timing synchronization.

For example, the multiple uplink timing operating method of the base station 100 according to the present invention can estimate the UL timing error in the random access (RA) process with the terminal 2 by referring to the terminal 2 belonging to the second terminal group (4b in Fig. 4 or 6b in Fig. 6) slowing the uplink transmission timing of the terminal 2 by a specific time relative to the reference uplink transmission timing based on the estimation result ).

Accordingly, in the multiple uplink timing operation method of the base station 100 according to the present invention, a random access response (RAR) message including a timing command TA constructed in the course of a random access (RA) Thereby performing uplink transmission timing synchronization with the terminal 2. [

The multi-uplink timing operation method of the base station 100 according to the present invention is a method of operating a multiple-uplink timing operation in a connection mode of the UE 2 after random access (RA) ) To the terminal 2 so that the uplink transmission timing which can not be compensated by the timing command TA during the movement of the terminal 2 or during the random access (RA) is called the second uplink transmission timing (4b in Fig. 4, 6b.

For example, the multi-uplink timing operation method of the base station 100 according to the present invention refers to the terminal 1 belonging to the first terminal group, and estimates the UL timing error in the random access (RA) , And based on the estimation result, the uplink transmission timing of the terminal 1 is compared with the first uplink transmission timing (4a or 4a in Fig. 4) which is slower by a certain number of symbols than the second terminal group (the second uplink transmission timing) 6a of FIG. 6).

Accordingly, the multiple uplink timing operation method of the base station 100 according to the present invention transmits a RAR message including the timing command TA constructed in the course of the random access (RA) with the terminal 1 to the terminal 1, Lt; RTI ID = 0.0 > 1 < / RTI >

The multi-uplink timing operation method of the base station 100 according to the present invention further includes a timing command (TA) of the MAC CE adaptively adjusting the uplink transmission timing in the connection mode of the UE 1 after the random access (RA) ) To the terminal 1 so that the uplink transmission timing which can not be compensated by the timing command TA during the movement of the terminal 1 or during the random access (RA) is called the first uplink transmission timing (4a in Fig. 4, 6a.

Here, the second terminal group is synchronized by the present invention at a second uplink transmission timing that is slower than the reference uplink transmission timing by a specific time.

At this time, the specific time may be a specific number, for example, one symbol time (FIG. 4) or a specific number, i.e., a time obtained by subtracting the UL to DL switching time required for uplink / ).

Hereinafter, for convenience of explanation, FIG. 4 will be described.

That is, the second terminal group (Group B) has the second uplink transmission timing (4b, 2071.3542) which is slower than the reference uplink transmission timing (2000 占 퐏) by a specific time (= 1 symbol 71.3542 占 퐏) lt; / RTI >

As shown in FIG. 4, the first terminal group (Group A) has a first uplink transmission timing (4a) that is slower than the second terminal group 4b by a specific number, that is, one symbol (= specific time 71.3542s) ), In other words, the first uplink transmission timing (4a, 2142.7083 μs), which is slower than the reference uplink transmission timing (2000 μs) by two symbols (= 142.7083 μs).

The multiple uplink timing operation method of the base station 100 according to the present invention is characterized in that for the first and second terminal groups, the uplink sub-frame (UL) of the first and second uplink transmission timings, (E.g., 1) symbols are not used for uplink transmission (transmission cutoff setting, S120).

In more detail, the multi-uplink timing operation method of the base station 100 according to the present invention sets up the last one symbol in the uplink sub-frame UL to be dedicated to SRS transmission, The last one symbol in the uplink subframe UL may not be used for the uplink transmission at the time when the SRS transmission period comes, in a manner of setting the maximum length (e.g., 320 ms) (S120).

In this case, since the terminals 1 and 3 belonging to the first terminal group are dedicated to SRS transmission in the last one symbol in the uplink sub-frame (UL) of the first uplink transmission timing synchronized under the control of the base station 100 The last one symbol in the uplink sub-frame (UL) will not be used for uplink transmission, since the SRS will also be transmitted intermittently because it will not transmit uplink data and the SRS transmission period comes at a very long time interval .

In addition, in the last one symbol in the uplink sub-frame (UL) of the second uplink transmission timing synchronized under the control of the base station 100, the terminals 2, 4 and 5 belonging to the second terminal group transmit the SRS transmission- Because the SRS will not transmit uplink data and the SRS transmission period arrives at a very long time interval, the SRS will also transmit very intermittently, so that the last one symbol in the uplink subframe (UL) will be.

In addition, the multiple uplink timing operation method of the base station 100 according to the present invention is characterized in that, for the first and second terminal groups, an uplink symbol after the guard time (GP) symbol in the special subframe S, Is set not to be used for uplink transmission (transmission interruption setting, S130).

More specifically, the multi-uplink timing operation method of the base station 100 according to the present invention sets UpPTS symbols for dedicated SRS transmission in a special subframe S, It can be prevented from being used for link transmission.

In this case, since the terminals 12, 3, 4, and 5 belonging to the first and second terminal groups do not transmit uplink data because they are dedicated to SRS transmission in the UpPTS symbol in the special subframe S, The UpPTS symbol in the frame S will not be used for uplink transmission.

As described above, in the multi-uplink timing operation method of the base station 100 according to the present invention, by setting the last symbol of the UpPTS and the uplink sub-frame (UL) not to be used for uplink transmission , And the frame structure of different uplink transmission timings due to the operation (synchronization) of multiple uplink transmission timings can coexist without overlapping.

In the multiple uplink timing operation method of the base station 100 according to the present invention, UL scheduling is performed so that only uplink subframes (UL) that do not overlap with each terminal group are used for uplink transmission (S140) The frame structure of different uplink transmission timings according to the operation (synchronization) of the transmission timing can coexist without overlap.

More specifically, the method of operating multiple uplink timings of the base station 100 according to the present invention is a method for operating multiple uplink sub-frames (UL) in a frame according to a second uplink transmission timing in a frame Allocate uplink resources to use the last uplink subframe (UL) for uplink transmission so that the symbols not used for uplink transmission and the downlink subframe (DL) in the last uplink subframe (UL) .

Referring to FIG. 4, a method for operating multiple uplink timings of the base station 100 according to the present invention is characterized in that for a second terminal group (Group B), a special sub-frame (S) and a downlink sub- (UL) of the two uplink sub-frames (UL) following the second uplink transmission timing (4b, 2071.3542 占 퐏) between the uplink sub-frame And allocates uplink resources.

In this case, each terminal 2, 4, 5 belonging to the second terminal group (Group B) will transmit the uplink data using the second uplink sub-frame (UL), and the second uplink transmission timing 4b, 2071.3542 the last one symbol of the second uplink subframe UL (14 symbols) is equal to the first one symbol of the downlink subframe DL (DL symbol) Will be matched.

However, according to the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), downlink data is normally transmitted in the downlink sub- Lt; / RTI >

Meanwhile, the multi-uplink timing operation method of the base station 100 according to the present invention is a method for operating multiple uplink timings of a first UE group, in which the uplink immediately before the last uplink sub-frame UL of two or more uplink sub- The uplink resource is allocated to use the link sub-frame (UL) for uplink transmission, and a symbol not used for uplink transmission in the immediately preceding uplink sub-frame (UL) (UL) are matched by a certain number of symbols.

Referring to FIG. 4, a method for operating multiple uplink timings of the base station 100 according to the present invention is characterized in that for a first terminal group (Group A), a special sub-frame (S) and a downlink sub-frame (DL) (UL), that is, the first uplink sub-frame (UL) of the two uplink sub-frames (UL) according to the first uplink transmission timing (4a, 2142.7083 占 퐏) To allocate uplink resources.

In this case, each of the terminals 1 and 3 belonging to the first terminal group (Group A) will transmit the uplink data using the first uplink subframe (UL), and the first uplink transmission timing (4a, 2142.7083 μs) (71.3542 mu s) with respect to the second terminal group, the last one symbol of the first uplink subframe UL (14 symbols) is the same as that of the second uplink subframe UL used by the second terminal group It will match the first one symbol.

However, in the present invention, since the last one symbol of the uplink sub-frame (UL) is set not to be used for uplink transmission (transmission interruption setting), the second uplink sub- The uplink data may be transmitted.

In the multiple uplink timing operation method of the base station 100 according to the present invention, in step S130, the UpPTS symbol in the special subframe S is set not to be used for uplink transmission (transmission blocking setting).

Accordingly, in the present invention, the uplink transmission time is shortened to the maximum through the transmission blocking setting for the last symbol of the UpPTS and the uplink sub-frame, and the uplink sub-frame use (UL scheduling) And this time is used as a guard period.

4, the time from the GP symbol in the special subframe S to the symbol immediately before the first uplink subframe (UL) used for uplink transmission for the first terminal group (Group A) GP). In other words, it can be seen that the time available for the first terminal group (Group A) to be acquired by the GP is extended up to 285.4166 μs.

4, the time from the GP symbol in the special subframe S to the symbol immediately before the second uplink subframe (UL) used for uplink transmission for the second terminal group (Group B) GP). In other words, in the case of the second terminal group (Group B), it can be seen that the time that can be secured by the GP is extremely long, at most 1000 μs or more.

Therefore, according to the present invention, the long guard time (GP) of the first terminal group (Group A), that is, the protection time (GP) of the terminals 1 and 3 in the first terminal group (Group A) It can be seen that the maximum cell radius that can be supported is determined.

In order to support a large cell in the frame structure of the existing LTE-TDD, it is inevitable to set the guard time (GP) to be long by lowering the weight of the DwPTS of the special subframe S and increasing the weight of the GP. In this case, do.

However, as described above, according to the present invention, by implementing a new technique for operating (synchronizing) multiple uplink transmission timings (hereinafter, referred to as a multi-uplink transmission timing operation scheme), the DwPTS specific weight of the special sub- It is possible to secure a sufficient protection time (GP) for the terminal to be sensed without lowering, so that it is possible to allocate more resources to the downlink and improve the downlink transmission speed while supporting a larger cell radius.

According to the present invention, since each of the terminals in the first and second terminal groups uses only the limited uplink sub-frame (UL), a downlink sub-frame (DL) is allocated to each terminal group You need to schedule it appropriately.

In this regard, the multiple uplink timing operation method of the base station 100 according to the present invention schedules a downlink subframe (DL) to each terminal group considering ACK / NACK transmission for each of the first and second terminal groups (S150).

In more detail, the multiple uplink timing operation method of the base station 100 according to the present invention may include, for each of the first and second terminal groups, an uplink subframe location used by the terminal group for uplink transmission in a frame, In step S150, a downlink sub-frame in a frame and a sub-frame to be used for downlink transmission in a special sub-frame are determined based on a minimum response waiting time and a minimum response waiting time for uplink transmission.

That is, in the case of the first terminal group, the multiple uplink timing operation method of the base station 100 according to the present invention is a method in which the uplink subframe position (the first half frame reference) Based on the minimum response waiting time for the downlink transmission (after the fourth sub-frame (4 ms)) and the minimum response waiting time for the uplink transmission (after the fourth sub-frame (4 ms) The sub-frame to be used for the downlink transmission among the downlink sub-frame DL and the special sub-frame S is determined.

Also, in the case of the second terminal group, the method of operating the multiple uplink timing of the base station 100 according to the present invention is a method in which the uplink subframe location (the second half frame basis) Based on the minimum response waiting time for the downlink transmission (after the fourth sub-frame (4 ms)) and the minimum response waiting time for the uplink transmission (after the fourth sub-frame (4 ms) The sub-frame to be used for the downlink transmission among the downlink sub-frame DL and the special sub-frame S is determined.

Accordingly, the multi-uplink timing operation method of the base station 100 according to the present invention can be applied to an LTE-TDD frame having a configuration 1 structure, two terminal group operations, and a minimum response waiting time for a downlink transmission 4 ms) and a minimum response waiting time for uplink transmission (after the fourth subframe (4 ms)), the first and second subframes (first down Link sub-frame DL and the first special sub-frame S) and determine the fifth sub-frame (second downlink sub-frame DL) in the second terminal group (Group B).

In this case, the multi-uplink timing operation method of the base station 100 according to the present invention is a method for operating the multiple uplink timing of the base station 100 according to the present invention, for each of the first and second terminal groups, Allocates downlink resources to use the first and second subframes (the first downlink subframe DL and the first special subframe S) for downlink transmission for the group A, B), DL scheduling can be performed by allocating downlink resources to use the fifth sub-frame (second downlink sub-frame DL) for downlink transmission.

Hereinafter, a case will be described in which the SRS is transmitted in the terminal group that has arrived at the SRS transmission period.

The multiple uplink timing operation method of the base station 100 according to the present invention is a method in which when an SRS transmission period set in a specific terminal group of any one of the first and second terminal groups arrives (S160 Yes) Uplink resources are allocated to use the last symbol in the uplink sub-frame (UL) of the time point for SRS transmission (S170).

In addition, in the multiple uplink timing operation method of the base station 100 according to the present invention, the uplink subframe (UL) of another terminal group overlapping with a symbol transmitting a SRS in a specific terminal group is set to not be used for uplink transmission (S170).

For example, it is assumed that the first terminal group of the first and second terminal groups is a specific terminal group arriving at an established SRS transmission period (for example, 320 ms).

The multiple uplink timing operation method of the base station 100 according to the present invention is a method in which the SRS transmission period (for example, 320 ms) set in the first terminal group arrives and is used for the uplink transmission at the time when the SRS transmission period arrives And allocates uplink resources to use the last symbol in the first uplink sub-frame (UL) for SRS transmission.

In this case, the UEs 1 and 3 belonging to the first UE group will transmit SRSs from the last symbol in the first uplink subframe (UL) that transmits the uplink data at the time when the SRS transmission period arrives.

In this case, in the multiple uplink timing operation method of the base station 100 according to the present invention, a second uplink sub-frame (UL) of a second terminal group overlapping a symbol for transmitting SRS in the first terminal group is used for uplink transmission (Transmission blocking setting).

This transmission interruption setting can be performed according to the determination of the base station 100, and can be solved when the base station 100 adjusts the UL scheduling for the second terminal group according to the transmission timing of the SRS.

As described above, the multi-uplink timing operation method of the present invention can be applied to an LTE-TDD system by implementing a new technique of operating (synchronizing) two or more uplink transmission timings, i.e., multiple uplink transmission timings, It is possible to allocate more resources to the downlink to improve the downlink transmission rate while supporting a larger cell radius by setting (ensuring) the GP sufficiently long.

The multiple uplink timing operation method according to an exemplary embodiment of the present invention may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

According to the multi-uplink timing operating apparatus and the multi-uplink timing operating method according to the present invention, the GP is set long enough (secured) to support a larger cell radius, and more resources are allocated to the downlink, It is not only the use of the related technology but also the possibility of commercialization or operation of the applied device is sufficient and it is practically possible to carry out clearly, Invention.

1, 2, 3,
100: multiple uplink timing operating device (base station)
110: terminal group classifying unit 120: multiple uplink synchronizing unit
130:

Claims (20)

delete A multiple uplink timing operating device,
A terminal group classifying unit for classifying a plurality of terminals into two or more terminal groups;
A plurality of uplink synchronization units for performing synchronization to have different uplink transmission timings from each other in each terminal group;
And a controller for allocating uplink resources so that the number of symbols used for uplink transmission in the uplink subframe of each synchronized uplink transmission timing is decreased for each terminal group,
Wherein the two or more terminal groups comprise:
A second terminal group synchronized with a second uplink transmission timing that is slower than the reference uplink transmission timing by a specific time,
And a first terminal group synchronized with a first uplink transmission timing that is slower than a predetermined number of symbols by the second terminal group. 3. The method of claim 2,
The specific time is,
Wherein the predetermined number of symbol times is a time obtained by subtracting the UL to DL switching time required for the uplink / downlink switching in the specific number of symbol times or the specified number of symbol times. delete 3. The method of claim 2,
Wherein,
And sets the last certain number of symbols in the uplink sub-frame of the first and second uplink transmission timings, which are synchronized with each other, to be used for the uplink transmission for the first and second terminal groups, Link Timing Operator. 6. The method of claim 5,
Wherein,
The SRS transmission period is set to be as long as possible within a predefined tolerance range,
And the last certain number of symbols in the uplink subframe are not used for uplink transmission except when the SRS transmission period arrives. The method according to claim 6,
Wherein,
When an SRS transmission period set in a specific terminal group of the first and second terminal groups arrives, an uplink resource is allocated to use the last symbol in the uplink subframe at the time when the SRS transmission period arrives for SRS transmission Quot;
And sets up the uplink subframe of another terminal group that overlaps with the symbol for transmitting SRS in the specific terminal group to not be used for uplink transmission. 6. The method of claim 5,
A frame of a structure including at least two uplink sub-frames between a special sub-frame having a guard time (GP) symbol and a downlink sub-frame,
Wherein,
Allocating an uplink resource to the second terminal group so as to use the last uplink subframe of two or more uplink subframes following the second uplink transmission timing in the frame for uplink transmission, Wherein a symbol not used for uplink transmission and a downlink subframe in the subframe are matched for the specific time. 9. The method of claim 8,
Wherein,
Allocating an uplink resource to the first terminal group to use an uplink subframe immediately before the last of two or more uplink subframes following the first uplink transmission timing in the frame for uplink transmission, Wherein a symbol not used for uplink transmission in the immediately preceding uplink subframe and a last uplink subframe used by the second terminal group coincide with each other by the predetermined number of symbols. 10. The method of claim 9,
Wherein,
The uplink symbol after the guard time (GP) symbol in the special subframe is not used for uplink transmission,
A time from a guard time (GP) symbol in the special subframe to a symbol immediately before the uplink subframe used in uplink transmission is used as the guard time (GP) for the first terminal group,
And a time from a protection time (GP) symbol in the special subframe to a symbol immediately before the uplink subframe used for uplink transmission is used as the protection time (GP) for the second terminal group. Timing operating device. 11. The method according to claim 8 or 10,
Wherein,
The uplink symbol after the guard time (GP) symbol in the special subframe is dedicated to SRS transmission so that the uplink symbol after the guard time (GP) symbol in the special subframe is not used for uplink transmission Wherein the timing controller is configured to: 11. The method of claim 10,
Wherein,
For each of the first and second terminal groups, an uplink sub-frame position used by the terminal group in uplink transmission in the frame, a minimum response wait time for downlink transmission, and a minimum response wait time for uplink transmission, A sub-frame to be used for downlink transmission in the downlink sub-frame and the special sub-frame in the frame,
And allocates downlink resources for use in the downlink transmission for the determined subframe among the in-frame downlink subframe and the special subframe for each of the first and second terminal groups. Device. delete In a multiple uplink timing operating method performed by a base station,
A multiple uplink synchronization step for performing synchronization so as to have different uplink transmission timings from the other terminal groups for each of two or more terminal groups; And
And a scheduling step of allocating uplink resources for each terminal group so that the number of symbols used for uplink transmission in an uplink sub-frame of each synchronized uplink transmission timing is reduced,
Wherein the two or more terminal groups comprise:
A second terminal group synchronized with a second uplink transmission timing that is slower than the reference uplink transmission timing by a specific time,
And a first terminal group synchronized with a first uplink transmission timing that is slower than a predetermined number of symbols by the second terminal group. 15. The method of claim 14,
Wherein the scheduling step comprises:
And a first setting step of setting, for the first and second terminal groups, the last certain number of symbols in the uplink sub-frame of the first and second uplink transmission timings synchronized, so that they are not used for uplink transmission Wherein the timing of the uplink timing operation is one of the following: 16. The method of claim 15,
Wherein the first setting step comprises:
The SRS transmission period is set to be as long as possible within a predefined tolerance range,
Wherein the last certain number of symbols in the uplink subframe are not used for uplink transmission except when the SRS transmission period arrives. 17. The method of claim 16,
When an SRS transmission period set in a specific terminal group of the first and second terminal groups arrives, an uplink resource is allocated to use the last symbol in the uplink subframe at the time when the SRS transmission period arrives for SRS transmission Quot;
Further comprising setting an uplink subframe of another terminal group that overlaps with a symbol transmitting the SRS in the specific terminal group not to be used for uplink transmission. 16. The method of claim 15,
A frame of a structure including at least two uplink sub-frames between a special sub-frame having a guard time (GP) symbol and a downlink sub-frame,
Wherein the scheduling step comprises:
Allocating an uplink resource to the second terminal group so as to use the last uplink subframe of two or more uplink subframes following the second uplink transmission timing in the frame for uplink transmission, Wherein a symbol not used for uplink transmission in a subframe and a downlink subframe are matched for the specific time. 19. The method of claim 18,
Wherein the scheduling step comprises:
Allocating an uplink resource to the first terminal group to use an uplink subframe immediately before the last of two or more uplink subframes following the first uplink transmission timing in the frame for uplink transmission, Wherein a symbol not used for uplink transmission in the immediately preceding uplink subframe and a last uplink subframe used by the second terminal group are matched by the predetermined number of symbols. 20. The method of claim 19,
Wherein the scheduling step comprises:
And a second setting step of setting an uplink symbol after a guard time (GP) symbol in the special subframe to not be used for uplink transmission,
A time from a guard time (GP) symbol in the special subframe to a symbol immediately before the uplink subframe used in uplink transmission is used as the guard time (GP) for the first terminal group,
And a time from a protection time (GP) symbol in the special subframe to a symbol immediately before the uplink subframe used for uplink transmission is used as the protection time (GP) for the second terminal group. Timing operating method.

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