KR20160121781A - Method and apparatus for allocating uplink resources - Google Patents

Abstract

Provided is a method and an apparatus. The method incudes allowing terminals to transmit an uplink grant (UL Grant) for an unlicensed component carrier (UCC), and allocating an UL grant. The UL grant for the first terminal among terminals includes resource allocation information considering the transmission point of the uplink data of a second terminal among the terminals. So, the uplink resource of an unlicensed band considering the data transmission of the terminal can be allocated.

Description

[0001] The present invention relates to a method and apparatus for allocating uplink resources,

The present invention relates to an apparatus and method for allocating uplink resources for transmission of uplink data.

As the number of Internet users increases through mobile communication systems, mobile communication providers are seeking an efficient way to increase the capacity of a mobile communication system. The most efficient and intuitive way is to increase the bandwidth by securing additional license band frequencies for mobile communication systems. Mobile operators can efficiently provide mobile communication services through the exclusive use of the licensed band frequencies secured, but the cost of licensing and use of the frequencies is high and the licensed band frequencies allocated for mobile communication systems are limited Is a disadvantage. Therefore, the frequency of license-exempted band frequencies, television whitespace (TVWS), or licensed / license-exempted bands shared by mobile telecommunication carriers (hereinafter referred to as "license-exempt band") , And licensed band frequencies are under consideration for providing mobile communication services.

A communication system using the frequency of the license-exempt band has the following limitations.

First, the transmit power of the signal is limited to minimize the impact on other systems sharing the license-exempt band. Therefore, unlike the licensed band system, when the licensed band system and the license-exempted band system are installed in the same place, a coverage hole may occur in the unlicensed band system.

In addition, the license-exempt band frequencies should be used discontinuously or opportunistically for fair coexistence with adjacent license-exempt band systems. Therefore, the transmission reliability of the control channel and common channel used in the mobile communication system can be lowered. And, the frequency regulation of the license-exempt band must be observed.

For example, a system using a license-exempt band can perform a clear channel assessment (CCA) for data transmission, search for a channel in the frequency dimension, and determine whether to use the channel according to the result of the CCA However, even if a specific device occupies the channel according to the result of the CCA, the channel occupation time may be restricted according to the frequency regulation. In addition, it can not occupy the channel beyond the maximum channel occupation time, and the CCA must additionally be performed to re-occupy the channel.

Due to the limitations of such license-exempt systems, scenarios in which license-exempt bands complement each other are considered, rather than standalone systems, which use only license-exempt bands. In such a scenario, reliable control functions such as terminal control and mobility management are performed in the licensed band, and the traffic functions such as wireless transmission rate increase and wireless traffic load balancing can be supplemented by the license-exempt band.

That is, a system or a carrier operating in a licensed band performs control and traffic functions, and a system or carrier operating at an unlicensed band frequency performs a traffic function. This operation can be implemented through Carrier Aggregation (CA) technology. For example, in the CA configuration of the 3GPP LTE, the TDD carrier of the license-exempt band in which both the CA and the uplink / downlink between the FDD carrier in the license-granting band and the carrier in the license band (i.e. LTE) CA between carriers.

The cellular system using the license-exempt band has an advantage in that it can provide a mobile communication service with guaranteed quality of service by utilizing low-cost, rich frequency resources and advanced interference control technology. However, new coexistence techniques and interference control techniques are needed to comply with the various regulations of the license-exempt band and to coexist with other license-exempt band systems and to secure these advantages. In particular, devices operated in a license-exempt band occupy / use a channel, and when the carrier aggregation method is applied, there is a need for a carrier aggregation technique and a method of operation that take into consideration the characteristics of a license band and a license-exempt band. In addition, a reliable wireless transmission service based on the existing cellular system should be provided in order to reflect restrictions (characteristics) for operating the device in the license-exempted band.

One embodiment provides a method for allocating uplink resources of a license-exempt band in consideration of data transmission of a plurality of terminals.

Another embodiment provides an apparatus for allocating uplink resources of a license-exempt band in consideration of data transmission of a plurality of terminals.

According to one embodiment, a method of allocating resources for uplink data is provided. The resource allocation method includes transmitting an uplink grant (UL grant) to a plurality of terminals to a unlicensed component carrier (UCC) The uplink grant includes resource allocation information in which the transmission time of uplink data of the second terminal among the plurality of terminals is considered.

In the resource allocation method, the uplink grant for the first terminal includes resource allocation information for allowing the first terminal to perform a clear channel assessment (CCA) after the second terminal transmits uplink data .

In the resource allocation method, the uplink grant for the first terminal may include resource allocation information for allowing the first terminal to transmit uplink data after the second terminal transmits the uplink data.

The step of transmitting in the resource allocation method may include transmitting an uplink grant to a plurality of terminals through a licensed component carrier (LCC).

The resource allocation method may further include performing a clear channel assessment (CCA) in a license-exempt band before a transmitting step, and the transmitting step may include the steps of: , And transmitting the uplink grant to the plurality of terminals through the UCC.

In the resource allocation method, the uplink grant may include resource allocation information for transmitting uplink data through a channel of a license-exempted band occupied through the CCA.

The resource allocation method may further include transmitting a special signal for preventing another device from occupying the channel when occupying the channel of the license-exempt band through the CCA.

In the resource allocation method, the uplink grant includes a Physical Uplink Shared Channel (PUSCH) format defined by a transmission time point and a transmission end point of an uplink grant in units of subframes, slots, or symbols .

According to another embodiment, a method for transmitting uplink data is provided. The uplink data transmission method includes: receiving an uplink grant (UL grant) for a unlicensed component carrier (UCC) to a plurality of terminals; Performing a clear channel assessment (CCA) in a previous subframe of a subframe for uplink data, as indicated by the uplink grant; And if the channel is occupied by the CCA, transmitting the uplink data through the UCC.

The step of transmitting in the uplink data transmission method may include transmitting a special signal such that the channel occupied by the CCA can not be used by another device.

In the uplink data transmission method, when resources for uplink data are allocated consecutively according to the uplink grant, uplink data is transmitted without the CCA even in the next subframe of the subframe in which the uplink data is transmitted .

The step of performing the CCA in the uplink data transmission method comprises: randomly selecting a slot for performing the CCA among the slots included in the previous subframe; And performing the CCA at the selected slot.

The step of transmitting in the uplink data transmission method may include transmitting uplink data through some symbols or slots included in a subframe for uplink data.

The uplink data transmission method may further include a step of not transmitting uplink data upon receiving a special signal from a base station or another terminal.

According to yet another embodiment, there is provided a computer program product comprising at least one processor, a memory, and a wireless communication unit, wherein at least one processor executes at least one program stored in a memory to provide a plurality of terminals with a Unlicensed Component Carrier And transmitting an uplink grant (UL Grant) to the UCC of the plurality of UEs, wherein the uplink grant to the first UE among the plurality of UEs includes a step of transmitting uplink data A base station is provided, the base station including resource allocation information in which a time point is considered.

The uplink grant for the first terminal in the BS may include resource allocation information for allowing the first terminal to perform a clear channel assessment (CCA) after the second terminal transmits the uplink data .

The uplink grant for the first MS in the BS may include resource allocation information for allowing the first MS to transmit the uplink data after the second MS transmits the uplink data.

At least one processor in the base station may perform a step of transmitting the uplink grant to a plurality of terminals through a licensed component carrier (LCC) when performing the transmitting.

Wherein at least one processor at the base station further performs performing a clear channel assessment (CCA) in an unlicensed band before performing the transmitting step, and wherein the at least one processor is further configured to: When the channel is occupied by the license-exempt band through the CCA, it can perform the step of transmitting the uplink grant to the plurality of terminals through the UCC.

The at least one processor in the base station executes at least one program stored in the memory to further transmit a special signal for preventing the other apparatus from occupying the channel when occupying the channel of the license-exempt band through the CCA can do.

When uplink data is transmitted through the license-exempt band, the base station or the terminal can efficiently occupy the resources of the license-exempt band by performing the CCA efficiently.

1A and 1B are conceptual diagrams illustrating a method for allocating an uplink resource of a license-exempt band in a license band in cross-carrier scheduling.
FIGs. 2A and 2B are conceptual diagrams illustrating a method of allocating an uplink resource of a license-exempt band in self-scheduling.
3A to 3C are layout diagrams showing a mobile communication system in which a UCC is set and operated.
4A and 4B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to an embodiment does not overlap with each other.
5A and 5B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to another embodiment does not overlap with each other.
6A and 6B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to another embodiment does not overlap with each other.
FIGS. 7A and 7B are conceptual diagrams illustrating a method of allocating uplink resources so that a plurality of terminals transmit data at the same time according to an embodiment of the present invention.
8A and 8B are conceptual diagrams illustrating a method of allocating uplink resources to transmit data simultaneously by a plurality of terminals according to another embodiment.
9A and 9B are conceptual diagrams illustrating a method of allocating uplink resources to a UE through CCA of a base station according to an embodiment of the present invention.
10A and 10B are conceptual diagrams illustrating a method of allocating uplink resources to a UE through a CCA of a base station according to another embodiment.
11A and 11B are conceptual diagrams illustrating a method in which a UE transmits data after resource reservation / occupancy failure of a base station according to an embodiment.
12A and 12B are conceptual diagrams illustrating a method of allocating uplink resources so that data transmission of a UE does not overlap with a CCA time point of a base station according to an exemplary embodiment.
13A and 13B are diagrams illustrating a method of scheduling a base station to duplicate uplink resources to a plurality of terminals according to an embodiment of the present invention.
14A and 14B are diagrams illustrating a method of scheduling an uplink resource to be duplicated to a plurality of UEs by another Node B in another embodiment.
15A and 15B are diagrams illustrating cross-carrier scheduling for uplink multiplexing according to an embodiment.
16A and 16B are diagrams illustrating self-scheduling for uplink multiplexing according to an embodiment.
17A and 17B are diagrams illustrating a data transmission method after UL Grant through self-scheduling according to an embodiment.
18 is a diagram illustrating a PUSCH format according to an embodiment of the present invention.
19 is a diagram illustrating a PUSCH format according to another embodiment of the UL Grant.
20 is a diagram illustrating cross carrier scheduling in which the CCA according to an embodiment is an FBE scheme.
FIG. 21 is a diagram illustrating cross carrier scheduling in which the CCA according to an embodiment is an LBE scheme.
22 is a diagram illustrating self-scheduling in which the CCA according to an embodiment is an FBE scheme.
23 is a diagram illustrating self-scheduling in which the CCA according to an embodiment is an LBE scheme.
FIG. 24 is a diagram illustrating a method in which a CCA is performed once when the CCA according to an embodiment is the FBE scheme, and a channel is occupied through self-scheduling.
FIG. 25 is a diagram illustrating a method in which a CCA is performed once when a CCA according to an embodiment is an LBE scheme, and a channel is occupied through self-scheduling.
26 is a diagram illustrating a possible uplink / downlink subframe structure according to an embodiment.
FIG. 27 is a diagram illustrating a transmission time point of uplink data in an uplink / downlink subframe configuration according to FIG. 26; FIG.
28 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment.
FIG. 29 is a diagram illustrating a transmission time point of uplink data in an uplink / downlink subframe configuration according to FIG.
30 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment.
31 is a diagram illustrating a transmission time point of uplink data in the uplink / downlink subframe configuration according to FIG.
32 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment.
FIG. 33 is a diagram showing a transmission time point of uplink data in an uplink / downlink subframe configuration according to FIG. 32; FIG.
34 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment.
FIG. 35 is a diagram illustrating a transmission time point of uplink data in an uplink / downlink subframe configuration according to FIG.
36 is a diagram illustrating a method of performing self-scheduling based on a frame configuration occupied by uplink and downlink at the same rate according to an embodiment.
FIG. 37 is a diagram illustrating a method for performing self-scheduling based on a frame configuration in which uplink and downlink are occupied at the same rate according to another embodiment.
38 is a diagram illustrating a method of allocating resources to a plurality of terminals according to an embodiment.
39 is a diagram illustrating a method of allocating resources to a plurality of terminals by cross carrier scheduling when the CCA according to an embodiment is an FBE scheme.
40 is a diagram illustrating a method of allocating resources to a plurality of terminals by cross carrier scheduling when the CCA according to an embodiment is an LBE scheme.
41 is a diagram illustrating a method of allocating resources to a plurality of terminals by self-scheduling when the CCA according to an embodiment is an FBE scheme.
42 is a diagram illustrating a method of allocating resources to a plurality of terminals by self-scheduling when the CCA according to an embodiment is an LBE scheme.
FIGS. 43 and 44 are diagrams illustrating a data transmission method of a terminal when a base station occupies both uplink and downlink channels simultaneously according to an embodiment.
45 and 46 are diagrams illustrating a data transmission method of a terminal when a base station according to another embodiment simultaneously occupies uplink / downlink channels.
47 and 48 are partial sub-frames of method 1 according to one embodiment.
49 and 50 are partial sub-frames of method 2 according to one embodiment.
51 and 52 are partial sub-frames of Method 3 according to one embodiment.
53 is a diagram illustrating a partial sub-frame of method 4 according to an embodiment.
54 is a diagram illustrating a partial sub-frame of method 5 according to one embodiment.
55 and 56 are partial sub-frames of method 1 according to another embodiment.
57 and 58 are partial sub-frames of Method 2 according to another embodiment.
59 and 60 are partial subframes of method 3 according to another embodiment.
61 and 62 are partial subframes of method 4 according to another embodiment.
63 is a block diagram illustrating a wireless communication system according to an embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present disclosure can be embodied in various different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention in the drawings, parts not related to the description are omitted, and like reference numerals are given to similar parts throughout the specification.

Throughout the specification, a terminal is referred to as a mobile station (MS), a mobile terminal (MT), an advanced mobile station (AMS), a high reliability mobile station A subscriber station (SS), a portable subscriber station (PSS), an access terminal (AT), a user equipment (UE), a machine type communication device MTC device and the like and may include all or some functions of MT, MS, AMS, HR-MS, SS, PSS, AT, UE,

Also, a base station (BS) is an advanced base station (ABS), a high reliability base station (HR-BS), a node B, an evolved node B, eNodeB), an access point (AP), a radio access station (RAS), a base transceiver station (BTS), a mobile multihop relay (MMR) (RS), a relay node (RN) serving as a base station, an advanced relay station (ARS) serving as a base station, a high reliability relay station (HR) (BS), a home Node B (HNB), a home eNodeB (HeNB), a pico BS, a macro BS, a micro BS ), Etc., and all or all of ABS, Node B, eNodeB, AP, RAS, BTS, MMR-BS, RS, RN, ARS, HR- And may include negative functionality.

FIGS. 1A and 1B are conceptual diagrams illustrating a method of allocating an uplink resource in a license-exempt band in cross-carrier scheduling, and FIGS. 2A and 2B are conceptual diagrams illustrating a method of allocating an uplink resource in a license-exempt band in self-scheduling.

1A and 1B are conceptual diagrams illustrating a method of allocating a license-based bandwidth for a frame-based equipment (FBE). FIGS. 1B and 2B illustrate a method of allocating a license-based bandwidth for a load- Fig. FBE and LBE are channel access methods defined in ETSI EN301.893 and 3GPP TR36.889 standards. The basic operation is based on the method specified in the specification, and in one embodiment, the channel occupation time is assumed to be 4 ms. Cross-carrier scheduling is a scheduling scheme in which a base station transmits a UL Grant for a unlicensed component carrier (UCC) to a UE through a licensed component carrier (LCC). And, the self-scheduling is a scheduling scheme in which a base station transmits a UL Grant for a UCC to the UE through the same UCC.

Referring to FIGS. 1A and 1B, a BS allocates resources (UL Grant) to a UE through cross-carrier scheduling. UE2 and UE4 are scheduled to transmit UL Grant in a PCell (primary cell) and transmit data to a base station at a time point after four subframes (FDD reference). At this time, if the PCell operates in TDD, the uplink scheduling time of the UE may be 4 to 7 subframes according to UL / DL (uplink / downlink) configuration. However, when UE2 and UE4 perform CCA for transmitting data at the scheduled time, if UE1 already occupies the channel, UE2 determines that the channel is occupied (or used) as a result of CCA Data can not be transmitted at the scheduled time. At this time, the other terminal may be a base station or another device operating in a license-exempt band such as WiFi. Similar problems can also occur in FIGS. 2A and 2B, which also illustrate the case of self-scheduling.

3A to 3C are layout diagrams showing a mobile communication system in which a UCC is set and operated.

Referring to FIG. 3A, an indoor and an outdoor low power cell in which an LCC and a UCC are operated in one cell are shown. In each case, the PCell may be a macro cell, and the secondary cell may be co-located or non-co-located with the PCell.

Referring to FIG. 3B, PCell in which LCC is operated and SCell in which LCC and UCC are operated (low power) are shown. Each SCell operating LCC and UCC can be deployed indoors and outdoors. The PCell may be a macro cell or a small cell, and the SCell in which the LCC is operated and the SCell in which the UCC is operated may be co-located with each other or non-co-located.

Referring to FIG. 3C, there is shown a PCell in which the LCC is operated and a (low power) SCell in which the UCC is operated. The SCell in which the UCC is operated can be placed indoors or outdoors, and the PCell in which the LCC is operated can be a macrocell or a small cell.

Hereinafter, an uplink resource scheduling method in the case where the UE performs CCA before data transmission will be described.

4A and 4B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to an embodiment does not overlap with each other.

4A and 4B, the uplink resource is allocated by the cross carrier scheduling. In order for the UE to transmit the uplink data using the resource allocated by the base station, the UE performs the CCA and can allocate resources (i.e., If the state is idle, the data can be transmitted.

Referring to FIG. 4A (FBE), the UE 2 is allocated an uplink resource so that the UE 2 does not perform the CCA for data transmission at the time of transmitting the data. Therefore, it is possible to prevent the CCA performance and the channel occupation by the UE 1 from being occupied during the CCA of the UE 2. Referring to FIG. 4B (LBE), the UE 4 can perform a CCA (or an extended CCA (Ext-CCA)) at a time point that is independent of the data transmission time of the UE 3. [ Since the uplink resources are continuously allocated to the UE 4 by the cross carrier scheduling, the UE 4 can continuously transmit data through one CCA operation without performing additional CCA.

5A and 5B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to another embodiment does not overlap with each other.

5A and 5B, an uplink resource is allocated by self-scheduling, and a base station performs a CCA to use a channel for allocating resources to the UE.

Referring to FIG. 5A (FBE), since the base station performs the CCA at a fixed location (idle period), the uplink resource must be allocated to the UE considering the time when the UE transmits data. In FIG. 5A, the UE 1 performs the CCA in the next subframe of the subframe where the uplink data transmission (UL data Tx) of the UE 2 occurs. Meanwhile, referring to FIG. 5B (LBE), a base station can relatively determine a CCA execution time when data transmission of a terminal is required. Therefore, the BS can flexibly adjust the channel occupancy time so that the UE can reuse the channel occupied by the UE before performing the CCA. Also, when resources are continuously allocated to a terminal, the terminal can transmit data using resources through one CCA operation.

6A and 6B are conceptual diagrams illustrating a method of allocating uplink resources so that uplink scheduling of a plurality of UEs according to another embodiment does not overlap with each other.

6A and 6B, the BS allocates the uplink resource by self-scheduling and performs the CCA to use the channel for allocating resources to the UE.

Referring to FIG. 6A (FBE), the base station allocates resources to the UE by adjusting the COT, and the UE performs the CCA before transmitting the data through the allocated resources. In this case, among the channel occupancy time (COT) of the base station of FIG. 5A and FIG. 5B, the first subframe of FIG. 5A may also be allocated an uplink resource by transmitting an UL grant. In FIG. 6B (LBE), the COT adjustment method of the base station of FIG. 6A (for example, according to this method, if the UL Grant is transmitted in the first subframe, the COT is terminated before the uplink data is transmitted through the allocated resource ) Can be applied.

Referring to FIG. 6B, since the CCA execution time is not fixed compared to the FBE and the CCA slot for the CCA can be randomly selected in the case of the Ext-CCA, the end point of the CCA is the transmission unit For example, the time of a subframe in the case of LTE). In the present invention, a special signal can be transmitted until data is transmitted to solve this problem. The special signal is indicated as 'RSV (reservation)' in FIG. The special signal may be similar to the signal transmitted by the base station during channel access / occupancy for downlink data transmission. For example, when a terminal performs a CCA (eg, WiFi, another base station (eNB), another terminal) operating in a license-exempt band to transmit data from a resource allocated by a base station for uplink data transmission A special signal can then be used to prevent access to / occupying the channel. The special signal shown in FIG. 6B may be used for LBE when resources are allocated through cross-carrier scheduling, or may also be used for FBEs.

FIGS. 7A and 7B are conceptual diagrams illustrating a method of allocating uplink resources so that a plurality of terminals transmit data at the same time according to an embodiment. FIG. 8A and FIG. FIG. 2 is a conceptual diagram illustrating a method of allocating upstream resources to a mobile station.

7A and 7B, uplink resources are allocated through cross-carrier scheduling, and uplink resources are allocated through self-scheduling in FIGS. 8A and 8B.

First, referring to FIGS. 7A and 8A to which the FBE is applied, the CCA execution time and the CCA execution time (interval) of a plurality of terminals to simultaneously transmit data can be set to be the same. Therefore, a plurality of terminals performing the CCA at the same time acquire the same CCA result (busy or idle) and perform data transmission at the same time when the channel is idle so that multiplexing between a plurality of terminals is implemented .

In FIGS. 7B and 8B, in which LBE is applied, the CCA execution time and the CCA execution time (interval) are set to the same for each terminal, so that the access / occupancy time of the channel of each terminal is applied equally

As described above, in the case of the LBE, the CCA execution time is not fixed as compared with the FBE. In the case of the Ext-CCA, since the CCA slot for the CCA execution can be randomly selected, And the RSV to which the special signal is transmitted may be used until the transmission of the data. The special signal may be similar to the signal transmitted at the base station for channel access / occupancy for downlink data transmission. For example, when a terminal performs a CCA (eg, WiFi, another base station (eNB), another terminal) operating in a license-exempt band to transmit data from a resource allocated by a base station for uplink data transmission A special signal can then be used to prevent access to / occupying the channel. The special signals of Figures 7b and 8b can be used in the FBE as well as in the LBE (i.e., similar or identical).

A plurality of terminals perform CCA and transmit data at the same time. The base station performs scheduling for data transmission of the terminal to the terminal, and after the terminal performs CCA before data transmission, reserves or reserves uplink resources. The terminal can also be applied to the data transmission method, which will be described in detail below with reference to FIG. 13 through FIG.

FIGS. 9A and 9B are conceptual diagrams illustrating a method of allocating uplink resources to a UE through a CCA of a base station according to an embodiment of the present invention. FIGS. 10A and 10B illustrate an uplink resource Is assigned.

According to the method shown in FIGS. 9A, 9B, 10A, and 10B, since the BS performs the CCA for data transmission on behalf of the UE, when a plurality of UEs performs the CCA It is possible to reduce the overhead that may occur.

However, in this case, after the CCA of the base station, the UE may not know whether the channel is occupied or not. For this purpose, the terminal can suppress the channel access / occupation of another apparatus by transmitting a special signal to another apparatus, such as the RSV of the LBE described above, that the channel occupies the channel at the time of data transmission. The special signal can be applied to the FBE CCA in the same or similar manner.

On the other hand, if the base station determines that the channel is occupied as a result of performing the CCA, the base station can inform the terminal through the license band that the resource reservation fails.

11A and 11B are conceptual diagrams illustrating a method in which a UE transmits data after resource reservation / occupancy failure of a base station according to an embodiment.

If there is no indication of the resource reservation failure of the base station or if the indication is omitted and the terminal does not know the resource reservation failure, the terminal can transmit data using the allocated resources irrespective of the CCA performance result. If it is determined that the channel is available and occupied as a result of the CCA of the base station, the terminal receives the special signal transmitted from the base station, determines that the channel can be occupied, and transmits data through the allocated resource. Alternatively, the base station may inform the terminal of the success or failure of the resource reservation through the license band. Referring to FIGS. 11A and 11B, the BS succeeds in occupying the channel as a result of the CCA for the first time, and then for each COT, each MS skips CCA and transmits data. However, the base station fails to occupy the channel as a result of the next CCA, but each terminal can transmit data from the allocated resource without recognizing the occupation failure of the channel (i.e., regardless of the occupation result).

12A and 12B are conceptual diagrams illustrating a method of allocating an uplink resource so that the CCA time of the base station and the data transmission time of the UE do not overlap.

Referring to FIG. 10A, since the uplink transmission of UE1 is scheduled at the time of performing the second and fourth CCA (additional CCA) of the base station, UE1 can not transmit data at that time. Also, referring to FIG. 10B, since the uplink transmission of UE3 is scheduled at the time of performing the fourth CCA of the base station, UE3 can not transmit data at that time.

12A and 12B, when the uplink data transmission of the UE is scheduled at a time when the COT of the base station is limited and additional CCA is required according to the frequency regulation, the CCA time of the base station and the data of the UE Resources may be allocated so that transmission times do not overlap each other. That is, the UL grant transmitted from the base station to the UE after the initial CCA execution may include resource allocation information for scheduling uplink data of each UE at a time point after the CCA of the base station.

13A and 13B are diagrams illustrating a method of scheduling uplink resources to a plurality of UEs at the same time according to an embodiment of the present invention. FIGS. 14A and 14B illustrate a method of scheduling uplink resources At the same point in time.

13A and 13B, uplink resources are allocated to a plurality of terminals through cross carrier scheduling, and uplink resources are allocated to a plurality of terminals through self-scheduling in FIGS. 14A and 14B.

13A, 13B, 14A, and 14B, since the BS reserves resources for occupying / using the channel through the CCA, the BS assigns resources to two or more UEs at the same time, .

In this case, when the BS occupies / uses the channel after the CCA, the BS can notify the MS that has received the UL Grant for data transmission that the channel is occupied by transmitting a special signal. Then, the terminal can transmit data through the resources allocated by the UL Grant. This "CCA + RSV (reservation)" can be made in every uplink data transmission unit (for example, in subframe units) and several data transmission units can be reserved. At this time, even if the data transmission point of the terminal is allocated, for example, by two or three data transmission units through the special signal transmitted after the CCA, the terminal can transmit data (omitted) without performing additional CCA have. If a special signal is not transmitted, the terminal receiving the UL Grant determines that the channel is occupied by another device and does not transmit data from the resource allocated by the UL Grant.

On the other hand, a special signal can be detected through " energy detection ", or "signal detection" Such a special signal can be similarly applied even when uplink resources are allocated through self-scheduling of a base station. Unlike the downlink data, a special signal for the uplink data can be newly defined. In this case, a newly defined special signal can be applied for downlink data reception and uplink data transmission of the terminal. Or a period during which downlink data and uplink data are transmitted. When a special signal is transmitted in a predetermined period, the terminal can determine whether to use the channel through a special signal and occupy / use the channel. Also, the special signal may be defined in a physical control channel or a physical control channel indicating information used for resource allocation, such as a PDCCH defined in LTE, in the same or similar form as information indicating resource allocation May be defined.

Hereinafter, a method in which a plurality of terminals simultaneously transmit data in a license-exempt band will be described.

In order to allocate resources for data transmission to a plurality of terminals, a base station may allocate resources to each terminal or allocate resources to a plurality of terminals collectively at a time. When a base station allocates resources to a plurality of terminals all at once, a parameter and a parameter value for performing CCA can be applied to a plurality of terminals equally. The method of allocating resources is described on the basis of the 3GPP LTE system, but can be applied to other radio access systems.

The operations of the base station and the terminal for performing the CCA and transmitting data are as follows.

According to one embodiment, when a base station allocates resources (UL Grant) to a terminal using a PDCCH, the base station can additionally transmit parameter values (set values) for performing CCAs. At this time, the set value for performing the CCA may be included in the PDCCH, or may be delivered in an upper layer such as the RRC layer (i.e., RRC level signaling) or may be transmitted through a MAC control element And a predefined set value for performing the CCA may be used between the base station and the terminal. According to one embodiment, a set value for performing CCA may be selected at a time of CCA execution, a CCA slot (for example, in the case of LBE, randomly selected from 1 to q to perform Ext-CCA) And may be a value for performing CCA in case of FBE), and a fixed frame period for FBE operation in case of a UE set as FBE. At this time, the fixed frame interval is always applied with the same value, or a predetermined or predefined value may be used. If a setting value for performing CCA is not received from the base station, the terminal may arbitrarily select a setting value for performing the CCA, or may select a setting value for performing the CCA according to the method defined in the regulation of the license-exempt band , Or the setting value previously received from the base station can be maintained as it is. In addition, if a CCA slot value where a count down is determined to be "busy" by judging a previous CCA channel as a result of the previous CCA exists and the channel is again "busy" (or occupied) as a result of the next CCA, The UE can reuse the CCA slot value freezed in the next CCA operation and send the channel while counting down the CCA slot value again.

According to another embodiment, in order to transmit a physical uplink shared channel (PUSCH) (i.e., UL data), a terminal receiving the UL grant instructs to transmit a special signal to the terminal before the transmission of the PUSCH .

The special signal transmission indication may be included in the PDCCH, or may be separately transmitted when there is a time before the PUSCH transmission after the CCA is performed. Otherwise, the base station does not transmit the special signal. When a BS occupies resources for a UE and uses resources for the UE, the BS performs a CCA and transmits UL GRANT if the channel can occupy the UE.

The special signal may be instructed to be transmitted to each terminal in the UL Grant, or may be indicated to be included in the PDCCH to be transmitted only to a specific terminal (for example, a terminal performing the CCA) or some terminals.

In another embodiment, except for the resources for data transmission (PUSCH), the setting values of the CCA execution time, the CCA slot, and the like may be transmitted with the same value. In this case, the terminal is instructed to simultaneously transmit data. The CCA timing may be set at a time immediately after the downlink data transmission of the base station (subframe unit, slot unit, symbol unit, or the like), or at the start time of a specific subframe, For example, starting position of a slot, a specific symbol in a subframe). Similarly, the CCA end point can be set to the end time of a specific subframe or slot, a specific symbol, and the like. A special signal is set to be transmitted from the CCA execution point to the CCA end point so as to prevent another device from accessing the channel or occupying the channel during the time from the CCA execution point to the CCA execution end point, .

The terminal receiving the UL grant from the base station performs the CCA at a later set time using resources allocated by the UL Grant. In this case, the CCA performance can be based on the CCA value set for transmitting the data. For the 'set time' below, PCell (FDD standard) transmits UL Grant and explains with reference to after 4 subframes. The 'set time' may vary according to the UL / DL configuration (for example, 4 to 7 subframes) in TDD, and the basic timing specified in 3GPP TS36.211, 36.212, 36.213, etc. may be applied. If it is determined that the channel is "busy or occupied" as a result of the CCA of the terminal, the terminal can notify the base station of the occupation of the channel through the license band without transmitting data.

However, if it is determined that the channel is idle as a result of the CCA, the UE transmits data. If channel access / occupancy is possible, the terminal transmits a special signal if necessary, and transmits the PUSCH through the allocated resource.

The UE performs the CCA before each data transmission and can determine whether the data is transmitted through a special signal at a specific time point (for example, at the beginning of the UL section) instead of occupying the channel, or transmit data according to the transmission unit . At this time, the base station may transmit the special signal or may be transmitted by the terminal performing the CCA. The special signal may be used to determine that the CCA result channel is available, or may be used to match a transmission unit (e.g., a subframe boundary) for data transmission.

The operation of the base station and the terminal for transmitting and receiving the special signal is as follows.

The special signal according to one embodiment may be transmitted by the base station or the terminal. When a base station attempts resource reservation through CCA for data transmission of a terminal, the base station can transmit a special signal to the base station. Or a special signal may be transmitted from the terminal performing the CCA for data transmission.

The determination as to whether or not the channel is occupied by the special signal and the operation according to the determination can be performed as follows.

The subject (base station or terminal) performing the CCA transmits a special signal when it is determined that the CCA result channel can be occupied. At this time, if it is determined that the channel is already occupied by another device as a result of the CCA, the BS or the UE does not transmit the special signal because the channel can not be occupied / used.

A terminal that has transmitted a special signal can transmit data using resources allocated from a base station.

The base station that has transmitted the special signal can prepare (expect) the reception of data from the terminal to which resources are allocated through the UL Grant.

When a terminal receives a special signal from a base station or another terminal, the terminal transmits data using resources allocated by the base station.

In this case, the special signal includes a physical downlink control channel (PDCCH), a physical random access channel (PRACH), a sounding reference signal (SRS) ), A physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), or an uplink dedicated demodulation reference signal (DMRS) (E.g., "111 ... 111 "," 101010 ... ", etc.) that can be repeatedly transmitted over some or all or all bands.

The resource for transmission of the special signal may be all the subcarriers of the entire band used for the uplink, or may be transmitted only on the same subcarrier as the resource region allocated for the uplink data transmission, The resource area for transmission may be allocated by a base station, a preset resource area may be used, or may be set / indicated via a signal of an upper RRC level or via a MAC CE or the like.

FIGS. 15A and 15B are cross-carrier scheduling for uplink multiplexing according to an embodiment of the present invention, and FIGS. 16A and 16B illustrate self-scheduling for uplink multiplexing according to an embodiment.

As described above, when a plurality of terminals perform a CCA at the same time, each terminal performs a CCA based on the same CCA-related setting value at the same time, and transmits a special signal when the channel is occupied as a result of the CCA have. At this time, the terminal (UE2 or UE3 in FIGS. 15A, 15B, 16A and 16B) that has received the special signal for a predetermined time (for example, within Max COT) omits CCA for data transmission, Can be transmitted. The data at the time when the Max COT expires is scheduled in consideration of the case where the base station allocates resources, so that the frequency regulation can be observed. The data transmission format according to the frequency regulation is described in detail below.

Meanwhile, in FIGs. 13A and 16B, a terminal that has not received a special signal can perform a CCA by itself to transmit data, and then transmit a special signal. In order to provide services of two or more terminals, the same CCA-related information (for example, CCA time, CCA time slot, etc.) is provided to the terminal attempting data transmission at the same time, Can be set.

17A and 17B are diagrams illustrating a data transmission method after UL Grant reception through self-scheduling according to an embodiment.

As described above, at a specific point in time after receiving the UL Grant transmitted from the base station, the terminal transmits data from the allocated resource. At this time, a specific time point is a time point after 4 subframes after the UL Grant is transmitted in the PCell (FDD basis) or 4 ~ 7 subframes after the UL / DL configuration in TDD. However, due to frequency regulation for license-exempt band operation, the terminal may not be able to transmit data in a particular subframe. Therefore, according to one embodiment, a start / end point of a PUSCH in a subframe unit can be determined to be an arbitrary point in a subframe (fractional transmission; unit transmission shorter than a subframe unit). At this time, an arbitrary point in the subframe may be a start / end point of the slot or a specific symbol. In this case, the terminal can transmit data at a time point allocated to the UL Grant, irrespective of the frequency regulation of the license-exempt band. For example, referring to FIG. 17A, the UE 2 can not occupy all of the subframes allocated to the UL Grant. However, by terminating the data transmission in the slot or symbol in the corresponding subframe, the UE 2 can transmit the uplink data . In FIGS. 17A and 17B, a case where resource of a license-exempt band is allocated through self-scheduling has been described as an example, but also applicable to the case of cross-carrier scheduling.

FIG. 18 illustrates a PUSCH format according to an embodiment of the present invention. FIG. 19 illustrates a PUSCH format according to another embodiment of the present invention. Referring to FIG.

The UE can transmit the PUSCH at a specific point in time after receiving the UL Grant according to the format shown in FIG. Referring to FIG. 18, the PUSCH format defines a transmission time point and a transmission end point of uplink data in a slot unit, a subframe unit, or a specific time point (i.e., symbol unit) in a specific subframe. At this time, RSV (reserved) is a special signal and may be omitted in some cases. In the formats (e) to (h) of FIG. 18, the subframe i-1 may or may not be used as downlink data. Although the downlink data is shown in the format (a) to (d) of FIG. 18, it may not be used as downlink data.

Format (a) to (h) of FIG. 18 is a format that can be applied when the terminal performs CCA and transmits data. The formats (i) to (o) of FIG. 18 are formats that can be applied when a base station reserves resources. Even if a base station reserves resources, the terminal applies (a) to (h) . In the format (a) to (d) of FIG. 18, if the UE receives the UL Grant in the subframe i, it can transmit the uplink data in the subframe i + k (e.g., k = 4). The HARQ timing of the HARQ ACK / NACK for the case where the PUSCH is transmitted over two subframes as in the formats (h), (l), (m) and (o) (For example, the second (back) or the first).

Referring to FIG. 19, a UE receiving a UL Grant in a subframe m-4 can perform transmission after performing a CCA in a subframe m. Alternatively, when a UL Grant is transmitted to the UE in the subframe m, the UE can transmit data in a format of (a) to (o) to the subframe m + 4 in response to the UL Grant.

The formats (a) to (d) of FIG. 18 and FIG. 19 can be applied similarly to a special subframe according to the TDD frame format defined in the 3GPP LTE standard, CCA may be performed in some or all of the intervals set for the uplink pilot time slot (UpPTS) or SRS transmission, or in the first subframe after the special subframe.

Hereinafter, a method of adjusting the transmission time point of uplink data after UL grant reception will be described.

In order to operate according to the frequency regulation of the license-exempt band, the UE can set an arbitrary point in the subframe as the start / end point of the PUSCH, not in units of subframes at the time of allocation after UL grant reception. According to another embodiment, the base station can adjust the transmission time point of the uplink data to provide a service to the terminal.

In order to provide a service to the UE by adjusting the transmission time point of the UL data, the BS expects an uplink data reception time after UL Grant transmission in the sub-frame n, considering only the time actually occupied by the channel, The uplink data transmission time point after UL Grant reception in frame n can be determined and can be calculated according to the following equation (1).

In Equation (1), k is the UL grant transmitted from the base station defined in 3GPP and the transmission time point of the uplink data transmitted after the time point when the UE received (subframe n) (i.e., subframe n + k). k may be 4 to 7 (subframe) according to the UL / DL configuration when PCell is FDD and 4 (subframe) when PCell is TDD. T _inter-tx is the time (in subframe) from the subframe that received the UL grant to the uplink subframe occupied / available through the CCA.

FIG. 20 is a diagram illustrating cross-carrier scheduling in which a CCA according to an embodiment is an FBE scheme, FIG. 21 is a diagram illustrating cross-carrier scheduling in which a CCA according to an embodiment is an LBE scheme, FIG. CCA is an FBE scheme, and FIG. 23 is a diagram illustrating self-scheduling in which CCA according to an embodiment is an LBE scheme.

In Figs. 20 to 23, k is assumed to be 4, and in the case of TDD, k can be applied from 4 to 7. When the UE needs to generate and transmit uplink data, it can perform CCA and occupy the channel and transmit data.

20 and 21, in the case of uplink cross-carrier scheduling, resources are allocated through a license band, the terminal generates a virtual frame from the time when the UL Grant is received, Frame n) before the k (= 4) th sub-frame. If the channel occupies the channel after the CCA, the UE transmits the data at time n + k when the time when the data can be transmitted is less than or equal to k. However, if CCA is not occupied as a result of the CCA and the channel is occupied after CCA is additionally performed, since T _inter-tx becomes longer than k, the UE skips T _inter-tx , The time occupied by the channel is regarded as the uplink sub-frame, and the uplink data is transmitted. In this case, since the uplink resource is allocated by the cross carrier scheduling, when the UE receives the UL grant from the base station during the transmission of the uplink data, the terminal can generate a virtual frame from the received UL grant and transmit the data.

Referring to FIG. 22 and FIG. 23, in the case of UL self-scheduling, a base station performs a CCA for allocating resources through a UL grant and a CCA for transmitting uplink data. The virtual frame is generated from the resource allocation time point (UL grant reception point). When the channel is occupied up to the time point (n + k time point less than or equal to k) at which the CCA result data can be transmitted, the UE transmits the uplink data at the data transmission time point (n + k time point). However, if the channel is not occupied by the CCA and the channel is occupied after the CCA is further performed, since T _inter-tx becomes longer than k, the UE determines T _inter-tx at the time of data transmission (n + k) It considers only the channel occupation time after receiving the UL grant to be a subframe, and then transmits uplink data

Referring to FIG. 22 and FIG. 23, in the uplink data transmission through the uplink cross carrier scheduling and the self scheduling, the base station performs the CCA to transmit the UL Grant. In this case, the base station can include information related to 'RSV' transmitted after the CCA so that the channel occupation / use for UL grant transmission and the channel occupation / use for uplink data transmission can be distinguished. At this time, "RSV" may be used for time alignment (subframe boundary alignment) for data transmission after the additional CCA and for other devices (e.g., WiFi device, (ENB, UE, etc.). In this case, "RSV" includes a part or all of information for time / channel synchronization for data transmission, .

Referring to FIGS. 20 and 22, when the CCA of the FBE scheme is performed, the CCA for data transmission is performed in an idle period given constantly. Referring to FIG. 21 and FIG. 23, when the CCA of the LBE scheme is performed, the CCA for data transmission is performed before (immediately before) k time points for data transmission after UL grant reception.

If the UE receives a new UL Grant from the base station while the additional CCA is being performed, or if a predetermined time has elapsed or when the CCA can not transmit the uplink data at the time point n + k, the UE does not perform data transmission, Uplink data can be transmitted by UL Grant. Also, when the base station occupies resources for downlink data transmission at n + k time through the CCA, the UE transmits uplink data at n + k time point regardless of the UL grant transmitted from the base station at time n I can not.

FIG. 24 is a diagram illustrating a method in which a CCA is performed once when the CCA according to an embodiment is FBE scheme and occupies a channel through self-scheduling, FIG. 25 is a diagram illustrating a method in which a CCA FIG. 4 is a diagram illustrating a method in which a channel is occupied through self-scheduling once.

Referring to FIG. 24, when the CCA of the FBE scheme is performed, if the channel is not occupied by the terminal or the base station, the base station or the terminal waits until the next idle period and then performs CCA again. Referring to FIG. 25, when the CCA of the LBE scheme is performed, if the BS or the UE can not occupy the channel as a result of the CCA, the UE can immediately perform additional CCA to occupy the channel. The base station and the terminal commonly use the FBE scheme and the LBE scheme to generate a virtual subframe from the transmission / reception time of the UL grant, and generate a UL subframe in the kth subframe after the UL Grant reception subframe in the virtual subframe, . That is, since the DL / UL data can be transmitted through one CCA (resource allocation CCA), the UE may not further perform CCA for data transmission.

As described above, since the CCA is performed for upstream data transmission and the upstream data is transmitted due to the restriction of COT, the transmission time k of data after receiving UL grant may not be corrected.

FIG. 26 is a diagram illustrating a possible uplink / downlink subframe structure according to an embodiment, and FIG. 27 is a diagram illustrating a transmission time point of uplink data in an uplink / downlink subframe configuration according to FIG.

Referring to FIG. 26, a possible uplink / downlink subframe structure of a virtual frame generated from the UL Grant transmission / reception time is shown, and the COT after the CCA is 4ms. FIG. 27 shows a transmission time point of uplink data according to the subframe configuration shown in FIG. 26, and a time point at which uplink data is transmitted based on the current subframe is indicated in units of 1 ms. The transmission time point of the uplink data shown in FIG. 27 may be expressed by Equation (1). At this time, one subframe structure of the subframe structure shown in FIG. 26 can be applied to each CCA.

FIG. 28 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment, and FIG. 29 is a diagram illustrating transmission time points of uplink data in an uplink / downlink subframe configuration according to FIG.

Referring to FIG. 28, in order to transmit uplink data at a certain time point (for example, k = 4) after a subframe in which the UL Grant is received, a subframe configuration after the second CCA is determined depending on the first frame structure . For example, if the UL subframe of the first frame spans the last two subframes (No. 1), the first two subframes of the second subframe are composed of UL, and the remaining two subframes are denoted by DL In this case, the transmission time point of the uplink data can be guaranteed.

FIG. 30 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment, and FIG. 31 is a diagram illustrating transmission time points of uplink data in the uplink / downlink subframe configuration according to FIG.

Referring to FIG. 30, when the COT is 10 ms, the uplink / downlink subframe configuration according to another embodiment is similar to the TDD frame configuration defined in 3GPP. That is, a method of generating a virtual sub-frame by virtually connecting a frame configured for each CCA and transmitting the UL sub-frame for the first time at 4 ms after the sub-frame in which the UL Grant is received in the generated virtual sub- A new frame structure can be added. Therefore, the transmission time point of the uplink data is defined as shown in FIG. At this time, in the case of a subframe including both downlink and uplink, uplink data may not be transmitted and uplink data may be transmitted in the next UL subframe. That is, similar to the TDD frame configuration, except that all subframes are UL or DL (frame configuration No. 10), the same frame configuration can be specified for each CCA.

FIG. 32 is a diagram illustrating a possible uplink / downlink subframe structure according to still another embodiment. FIG. 33 is a diagram illustrating a transmission time point of uplink data in the uplink / downlink subframe configuration according to FIG. 32, FIG. 35 is a diagram illustrating a possible uplink / downlink subframe structure according to another embodiment, and FIG. 35 is a diagram illustrating a transmission time point of uplink data in the uplink / downlink subframe configuration according to FIG.

32 and 34, each frame structure repeatedly occupies DL / UL by 4 ms, FIG. 32 shows a case in which the channel occupation time is 4 ms, and FIG. 34 shows a case in which the channel occupation time is 10 ms . Referring to FIG. 33 and FIG. 35, the transmission time point of the uplink data after the subframe in which the UL Grant is received according to each frame configuration is fixed to k (= 4) in the virtually generated frame.

FIG. 36 is a diagram illustrating a method of performing self-scheduling based on a frame configuration occupied by the uplink and the downlink at the same rate according to one embodiment. FIG. 37 illustrates a method of performing self- FIG. 2 is a diagram illustrating a method of performing self-scheduling based on a frame configuration occupied by a ratio.

In FIG. 36, CCA is performed according to the FBE scheme, and in FIG. 37, CCA can be performed according to the LBE scheme. 36 and 37, the frame configuration occupies DL and UL at the same ratio (1: 1) when the channel occupation time is 4 ms, and the up / down subframes are occupied by 4 ms each . Referring to FIG. 36 and FIG. 37, information for identifying a consecutive frame constituting a virtual frame, such as when a specific frame starts with a DL sub-frame after the CCA and starts with a UL sub-frame after the next CCA , And may be included in a reservation signal transmitted after the CCA. For example, the reservation signal may include information about the first or second portion of the virtual frame, such as whether the frame begins with a DL subframe or a UL subframe. A reservation signal including information for distinguishing consecutive frames constituting a virtual frame can be applied even when the channel occupation time is not 4 ms (for example, 10 ms). In addition, the configuration of the second frame may be determined according to the configuration of the last four subframes of the first frame. For example, if the last subframe of the first frame is "DL, DL, DL (or DL + UL), UL", the beginning of the second frame may be configured as "UL, UL, UL, have. Further, the frame may be configured so that the M: N ratio (M? N) (for example, M DL subframes, N UL subframes) is repeatedly occupied.

The information for adjusting the transmission time of data after UL grant reception as described above may be included in a reservation signal (or an initial signal, preamble, etc.) transmitted before data is transmitted after the CCA, . Alternatively, it may be delivered (RRC level signaling) at an upper layer, delivered using a MAC CE or the like, or a predefined value may be used. At this time, the index (i.e., configuration number (configuration #)) generated by the indexing of the frame configuration is set in advance in the terminal, so that the data can be transmitted and received between the base station and the terminal according to the correct rule.

A method of adjusting the transmission time point of uplink data after UL grant reception (subframe n) in order to provide services to a plurality of terminals will be described below.

38 is a diagram illustrating a method of allocating resources to a plurality of terminals according to an embodiment.

For example, when UE1 performs CCA to transmit uplink data in subframe n + k, the channel is "busy ", and then uplink data is transmitted in subframe n + k + m The UE 1 transmits the uplink data in the subframe n + k + m, if the channel is "idle " as a result of additionally performing the CCA. However, if UE2 also performs CCA to transmit data in subframe n + k + m, UE1 and UE2 can simultaneously determine that the channel is "idle ", so that uplink data is transmitted from UE1 and UE2 The base station can not correctly receive the uplink data because it is transmitted to the base station. In order to solve this problem, 1) if uplink data is transmitted from a plurality of terminals to the same resource, the base station transmits a new UL Grant to a plurality of terminals to induce retransmission of uplink data, or 2) It is possible to prevent the uplink data from being transmitted at the same time. Or 3) the base station does not allocate the same resource on the frequency axis to a plurality of terminals during COT so as to be able to receive uplink data transmitted from a plurality of terminals, or 4) transmit uplink data It is possible to set the terminal not to transmit the uplink data in the subframe n + k if the channel is "busy " as a result of performing the CCA for transmitting the subframe n + k. At this time, if the CCA for transmitting the uplink data in the subframe n fails to occupy the channel and the uplink data transmission can not be performed, then the subframe (e.g., the subframe n + k + m ) May be included in the UL Grant, transmitted through the upper layer (RRC level signaling), or transmitted using MAC CE or the like, and may be transmitted in advance The set value may be used.

FIG. 39 is a diagram illustrating a method of allocating resources to a plurality of terminals by cross carrier scheduling when the CCA according to an embodiment is an FBE scheme. FIG. 40 is a flowchart illustrating a method of allocating resources to a plurality of terminals by cross- To a plurality of terminals.

In one embodiment, a method for transmitting the special signal and a method for adjusting the transmission time point of uplink data may be combined to provide services to a plurality of terminals.

39 and 40, when the base station allocates uplink resources (UL Grant) through the license band, the UEs (UE1 and UE3) receiving the UL Grant perform the CCA for uplink data transmission in the corresponding license- And occupies the channel. UE1 and UE3 transmit "RSV" when they occupy the channel through the CCA, and the base station which receives the uplink data (UL data Tx1 and UL data Tx2 ') "RSV" from the resource allocated through the UL Grant UL Grant The uplink data from the receiving terminal is expected and received. At this time, even if the base station does not receive the "RSV ", the base station can expect the uplink data and prepare to receive the uplink data. That is, even if "RSV" is not received, it is determined that the channel is "idle ", and the reception of the uplink data is ready. However, if "RSV" is not received for efficient data reception, it is determined that the channel is "busy" (i.e., the channel is occupied / used by another device), and the uplink data It may not be ready to receive. Referring to FIG. 39, in the case of the FBE, defer reception until the next idle period and expect to receive the "RSV " again. Referring to FIG. 40, in the case of LBE, it is possible to expect "RSV" continuously or to receive uplink data for a predetermined time or more.

Referring to FIG. 39, UE2 expects and prepares to receive "RSV " in a given idle period. If the UE 2 does not receive the "RSV " and determines that the channel is" idle ", the UE 2 occupies the channel and tries to transmit the uplink data using the allocated resources. The UE 2 blocks a channel to prevent channel occupation / use of another device until the uplink data (UL data Tx 2) is transmitted using the allocated resources. If UE2 does not receive the "RSV" and determines that the channel is "busy", UE2 does not transmit uplink data (UL data transmission (4)) and defer transmission until the next idle period.

Referring to FIG. 40, the UE 4 expects to receive the "RSV " after receiving the UL Grant and prepares to receive the" RSV ". As a result, similarly to the case of the FBE in FIG. 39, when the UE 4 does not receive the "RSV" and determines that the channel is "idle", the UE 4 occupies the channel and tries to transmit the uplink data through the allocated resource. At this time, the UE 4 blocks the channel so that another UE can not occupy / use the channel until the uplink data is transmitted using the allocated resources. On the other hand, when the UE 4 determines that the channel is "busy" because it can not receive the "RSV", the UE 4 delays the transmission of the RSV without transmitting the uplink data, After the subframe, until the next UL Grant reception, or during the instructed time). The base station informs the UE 4 of the time at which the transmission of the "RSV " is expected to be transmitted to the UE 3 at the time of transmitting the UL Grant, or transmits the UL Grant to the UE 4 so that the UE can expect / You can tell.

Then, the base station and the terminal judge that a frame for uplink data starts from the transmission / reception time of "RSV ", and generate a virtual frame and then adjust the transmission time point of the uplink data after UL grant reception. It can transmit and receive.

FIG. 41 is a diagram illustrating a method of allocating resources to a plurality of terminals by the self-scheduling when the CCA according to an embodiment is the FBE scheme. FIG. 42 illustrates a method of allocating resources by self-scheduling when the CCA according to an embodiment is the LBE scheme FIG. 8 is a diagram illustrating a method of allocating resources to a plurality of terminals.

Referring to FIG. 41 and FIG. 42, when a UL self-scheduling is applied, a base station allocates resources by performing CCA to occupy / use a channel and transmit UL grant. The UE attempts to transmit uplink data using the allocated resources. As described above, the terminal may transmit data using a channel occupied by the base station, or the terminal itself may occupy the channel and transmit data, as shown in FIG. 41 and FIG. At this time, the other terminals UE2 and UE4 can transmit data using "RSV" (i.e., receiving "RSV" instead of CCA).

FIGS. 43 and 44 are diagrams illustrating a data transmission method of a terminal when a base station occupies both uplink and downlink channels simultaneously according to an embodiment.

Referring to FIG. 43, the base station performs the CCA based on the FBE. Referring to FIG. 44, the base station performs the CCA based on the LBE, and each of the terminals UE1 to UE4 does not perform the CCA, RSV "to transmit the uplink data. At this time, the channel occupied by the base station is operated by a frame configuration, and the base station occupies a channel for transmission of uplink data (at the same time) in the channel occupation process for transmission of downlink data. In this case, the UE can transmit the uplink data from the resource allocated through the UL Grant to the Node B at the time of uplink data transmission of the virtual frame generated after the BS occupies the channel.

45 and 46 are diagrams illustrating a data transmission method of a terminal when a base station according to another embodiment simultaneously occupies uplink / downlink channels.

Referring to FIG. 45, the base station performs the CCA based on the FBE. Referring to FIG. 46, the base station performs the LBE-based CCA, and each terminal performs the RSV To transmit the uplink data. At this time, the base station applies a new frame configuration in another channel according to the frame configuration of the previously occupied channel, and the newly transmitted "RSV" includes an instruction to inform that a new frame configuration is applied unlike the previous information of "RSV" . Alternatively, the terminal may determine a frame configuration to be newly applied based on the previous frame configuration. Alternatively, the frame configuration information may be included in the PDCCH instead of being included in the "RSV ". Alternatively, the frame configuration information may be delivered (RRC level signaling) Alternatively, a predefined value may be used as the frame configuration information. At this time, the index (i.e., configuration number (configuration #)) generated by the indexing of the frame configuration is transmitted to the terminal in advance, so that data can be transmitted and received between the base station and the terminal according to the correct rule.

Hereinafter, the structure of a subframe that varies depending on a transmission format of data will be described in detail.

In order to transmit the uplink data, a part of the uplink data is used as a demodulated RS (DM-RS). However, as described above, a subframe (1 to N _Symb ^UL ) composed of only some symbols of a subframe (for example, a single carrier-frequency division multiple access (SC-FDMA) symbol) Hereinafter, referred to as "partial sub-frame"), the DM-RS must be changed.

First, in case of the partial sub-frame, if the number of symbols of the uplink sub-frame satisfies Equation (2) below, DM-RS is not included.

According to one embodiment, the DM-RS may be configured on a slot-by-slot basis. One resource block (RB) used for transmitting uplink data is a slot unit and is composed of a resource element (RE) index (k, l). In this case, k is the index (frequency-domain index) in the frequency domain, l is an index (time-domain index) in the time domain, N _Symb has a ^UL symbol number.

47 to 54 are diagrams illustrating a DM-RS in a partial sub-frame according to an embodiment.

In Figs. 47 to 54, a bold line indicates a partial sub-frame, and a hatched portion indicates DM-RS. Time method will be described below, is to have a symbol number of the section between the sub-frame is N _Symb ^UL more than or has the symbol ^{_{number, N Symb UL ~ 2 × N}} Symb UL, applied to the case constituting the DM-RS in slot units . If the CP is a normal CP, the number of symbols included in one slot is 7, and the symbol in which the DM-RS is located is the 4th (l = 3) symbol. When the CP is an extended CP, the number of symbols included in one slot is 6, and the symbol in which the DM-RS is located is the third (l = 2) symbol. However, in the case of the partial sub-frame, since DM is not guaranteed to be 3 or 2, the DM-RS can be located in the partial sub-frame according to the following method.

Method 1: The method (n = 0, 1, 2, ..., N _Symb ^UL -1) in which the DM-RS is included in the symbol with l = n.

47 and 48 are partial sub-frames of method 1 according to one embodiment. In Figures 47 and 48, n is 3, N _Symb ^UL is 7, and N _Symb ^{partial UL} of (a) - (g) are 7, 6, 5, 4, 3, 2, 1 in order.

인 심볼에 포함되는 방법.Method 2: DM-RS

Lt; / RTI > symbol.

49 and 50 are partial sub-frames of method 2 according to one embodiment. 49 and 50, N _Symb ^UL is 7 and N _Symb ^{partial UL} of (a) - (g) are 7, 6, 5, 4, 3, 2, 1 in order.

인 심볼에 포함되는 방법.Method 3: DM-RS

Lt; / RTI > symbol.

51 and 52 are partial sub-frames of Method 3 according to one embodiment. 51 and 52, N _Symb ^UL is 7, and N _Symb ^{partial UL} of (a) - (g) are 7, 6, 5, 4, 3, 2, 1 in order.

인 심볼에 포함되는 방법(n=0, 1, 2, ..., N_Symb ^UL-1).Method 4: DM-RS

(N = 0, 1, 2, ..., N _Symb ^UL -1).

53 is a diagram illustrating a partial sub-frame of method 4 according to an embodiment. 53, n is 3, N _Symb ^UL is 7, and N _Symb ^{partial UL} of (a) - (g) are 7, 6, 5, 4, 3, 2, 1 in order.

인 심볼에 포함되는 방법(n=0, 1, 2, ..., N_Symb ^UL-1).Method 5: DM-RS

(N = 0, 1, 2, ..., N _Symb ^UL -1).

54 is a diagram illustrating a partial sub-frame of method 5 according to one embodiment. 54, n is 3, N _Symb ^UL is 7, and N _Symb ^{partial UL} of (a) - (g) are 7, 6, 5, 4, 3, 2, 1 in order.

When the number of symbols included in the partial subframe is less than m (N _symb ^{partial UL} < m) (where m = 1, 2, ..., N _Symb ^{UL - 1} ), the DM-RS may not be included in the partial sub-frame.

According to another embodiment, the DM-RS may be configured in units of a transmission time interval (TTI). (However, if the number of symbols included in the partial subframe is less than N _Symb ^UL , Lt; / RTI &gt; slot). The number of symbols included in the partial sub-frame ^{_{N Symb UL ~ 2 × N Symb}} UL individual case, in total number of symbols ^{_{(N Symb UL ~ 2 × N}} Symb UL) unit (that is, in TTI units) DM-RS is .

Method 1: A DM-RS is not placed in a slot (partial slot) with fewer symbols than a normal slot.

55 and 56 are partial sub-frames of method 1 according to another embodiment.

Method 2: When the partial subframe includes a "slot + partial slot ", the DM-RS is included in a symbol of a fixed position in the slot (e.g., n = 3 if l = n).

57 and 58 are partial sub-frames of Method 2 according to another embodiment. In Figures 57 and 58, n is 3, N _Symb ^UL is 7, and N _Symb ^{partial UL} of (a) through (g) are N _Symb ^UL +7, N _Symb ^UL +6, N _Symb ^UL + 5, N _Symb ^UL + 4, N _Symb ^UL + 3, N _Symb ^UL + 2, N _Symb ^UL + 1. Referring to FIGS. 57 and 58, the DM-RS is fixedly placed at symbol # 3 in the slot, and thus the left slot of subframes (e), (f), and (g) the DM-RS is not arranged in the right slot of (e), (f), and (g).

인 심볼에 포함되는 방법.Method 3: DM-RS =

Lt; / RTI &gt; symbol.

59 and 60 are partial subframes of method 3 according to another embodiment. In Figure 59 and Figure 60, N _Symb ^UL is 7, (a) to (g) in N _Symb ^{partial UL} is N _Symb ^UL +7, +6 in the order N _Symb ^UL, N _Symb ^UL +5, N _Symb ^UL +4, N _Symb ^UL + 3, N _Symb + ^UL + 2, N _Symb ^UL + 1.

인 심볼에 포함되는 방법.Method 4: DM-RS is l =

Lt; / RTI &gt; symbol.

61 and 62 are partial subframes of method 4 according to another embodiment. In Figure 61 and Figure 62, N _Symb ^UL is 7, (a) to (g) in N _Symb ^{partial UL} is N _Symb ^UL +7, +6 in the order N _Symb ^UL, N _Symb ^UL +5, N _Symb ^UL +4, N _Symb ^UL + 3, N _Symb + ^UL + 2, N _Symb ^UL + 1.

Method 5: When the number of DM-RSs to be transmitted in the total TTI is N, the symbols included in the entire TTI are divided into N equals, and the DM-RS is included in each of N equally divided portions.

63 is a block diagram illustrating a wireless communication system according to an embodiment.

Referring to FIG. 63, a wireless communication system according to an embodiment includes a base station 6310 and a terminal 6320.

The base station 6310 includes a processor 6311, a memory 6312, and a radio frequency unit (RF unit) 6313. The memory 6312 may be coupled to the processor 6311 to store various information for driving the processor 6311 or at least one program to be executed by the processor 6311. [ The wireless communication unit 6313 is connected to the processor 6311 to transmit and receive wireless signals. The processor 6311 may implement the functions, processes, or methods proposed in the embodiments of the present disclosure. At this point, in the wireless communication system according to the embodiment of the present invention, the wireless interface protocol layer can be implemented by the processor 6311. The operation of the base station 6310 according to one embodiment may be implemented by the processor 6311. [

The terminal 6320 includes a processor 6321, a memory 6322, and a wireless communication unit 6323. The memory 6322 may be coupled to the processor 6321 to store various information for driving the processor 6321 or at least one program to be executed by the processor 6321. [ The wireless communication unit 6323 is connected to the processor 6321 to transmit and receive wireless signals. The processor 6321 may implement the functions, steps, or methods suggested in the embodiments of the present disclosure. At this time, in the wireless communication system according to the embodiment of the present invention, the wireless interface protocol layer can be implemented by the processor 6321. The operation of the terminal 6320 according to one embodiment may be implemented by the processor 6321. [

In an embodiment of the present disclosure, the memory may be located inside or outside the processor, and the memory may be connected to the processor through various means already known. The memory may be any type of volatile or nonvolatile storage medium, e.g., the memory may include read-only memory (ROM) or random access memory (RAM).

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, It belongs to the scope of right.

Claims (20)

A method for allocating resources for uplink data,
Transmitting an uplink grant (UL Grant) to a plurality of terminals to a unlicensed component carrier (UCC)
Lt; / RTI &gt;
Wherein the uplink grant to the first one of the plurality of terminals includes resource allocation information that considers the transmission time of the uplink data of the second one of the plurality of terminals. The method of claim 1,
The uplink grant for the first terminal includes the resource allocation information for allowing the first terminal to perform a clear channel assessment (CCA) after the second terminal transmits the uplink data. , Resource allocation method. The method of claim 1,
Wherein the uplink grant for the first terminal includes the resource allocation information for allowing the first terminal to transmit the uplink data after the second terminal transmits the uplink data. The method of claim 1,
Wherein the transmitting comprises:
Transmitting the uplink grant to the plurality of terminals via a licensed component carrier (LCC)
/ RTI &gt; The method of claim 1,
Before the transmitting step,
Performing a clear channel assessment (CCA) in the license-exempt zone
Further comprising:
Wherein the transmitting comprises:
Transmitting the uplink grant to the plurality of terminals through the UCC when the channel of the license-exempt band is occupied through the CCA;
/ RTI &gt; The method of claim 5,
Wherein the uplink grant includes the resource allocation information for transmitting the uplink data through a channel of the license-exempt band occupied through the CCA. The method of claim 5,
Further comprising the step of transmitting a special signal to prevent other devices from occupying the channel when occupying the channel of the license-exempt band through the CCA. The method of claim 1,
Wherein the uplink grant includes a physical uplink shared channel (PUSCH) format in which a transmission time point and a transmission end point of the uplink grant are defined in units of subframes, slots, or symbols. Way. A method for transmitting uplink data,
Receiving an uplink grant (UL Grant) for a unlicensed component carrier (UCC) from a base station;
Performing a clear channel assessment (CCA) in a previous subframe of a subframe for the uplink data, as indicated by the uplink grant; And
When the channel is occupied by the CCA, transmitting the uplink data through the UCC
And transmitting the uplink data. The method of claim 9,
Wherein the transmitting comprises:
Transmitting a special signal such that the channel occupied by the CCA can not be used by another device
And transmitting the uplink data. The method of claim 9,
Wherein the transmitting comprises:
If the resource for the uplink data is allocated consecutively according to the uplink grant, transmitting the uplink data without the CCA in the next subframe of the subframe in which the uplink data is transmitted
And transmitting the uplink data. The method of claim 9,
The step of performing the CCA comprises:
Randomly selecting a slot for performing the CCA among the slots included in the previous subframe; And
And performing the CCA in the selected slot. The method of claim 9,
Wherein the transmitting comprises:
Transmitting the uplink data through some symbols or slots included in a subframe for the uplink data
And transmitting the uplink data. 11. The method of claim 10,
Upon receiving the special signal from the base station or another terminal, not transmitting the uplink data
And transmitting the uplink data. At least one processor,
Memory, and
Wireless communication section
Lt; / RTI &gt;
The at least one processor executing at least one program stored in the memory,
Transmitting an uplink grant (UL Grant) to a plurality of terminals to a unlicensed component carrier (UCC)
Lt; / RTI &gt;
Wherein the uplink grant to the first one of the plurality of terminals includes resource allocation information that considers the transmission time of uplink data of the second one of the plurality of terminals. 16. The method of claim 15,
Wherein the uplink grant to the first terminal includes resource allocation information for allowing the first terminal to perform a clear channel assessment (CCA) after the second terminal transmits uplink data, Base station. 16. The method of claim 15,
Wherein the uplink grant for the first terminal includes the resource allocation information for allowing the first terminal to transmit the uplink data after the second terminal transmits the uplink data. 16. The method of claim 15,
Wherein the at least one processor, when performing the transmitting,
Transmitting the uplink grant to the plurality of terminals via a licensed component carrier (LCC)
. 16. The method of claim 15,
Wherein the at least one processor, prior to performing the transmitting,
Performing a clear channel assessment (CCA) in the license-exempt zone
Lt; / RTI &gt;
Wherein the at least one processor, when performing the transmitting,
Transmitting the uplink grant to the plurality of terminals through the UCC when the channel of the license-exempt band is occupied through the CCA;
. 16. The method of claim 15,
The at least one processor executing at least one program stored in the memory,
Transmitting a special signal for preventing another device from occupying the channel when occupying the channel of the license-exempt band through the CCA;
The base station further comprising:

Images