KR20180108342A - Method, apparatus, and system for transmitting and receiving/decoding control channel in wireless communication system - Google Patents

Abstract

The present invention relates to a method of a base station (eNB) transmitting information on a slot configuration to a downlink control channel in a mobile communication system using dynamic time division multiple access. The method comprises the steps of: receiving a UE group common PDCCH or a common PDCCH including a slot format or slot configuration information; receiving a specific-terminal PDDCH including information equal to or less than the slot format or slot configuration information; and determining the slot format or slot configuration information and whether a user terminal can be operated through the received UE group common PDCCH or common PDCCH and the specific-terminal PDCCH.

Description

Technical Field [0001] The present invention relates to a method, apparatus, and system for transmitting and receiving a control channel of a wireless communication system,

The present invention relates to wireless communication systems, and more particularly, to a method and apparatus for transmitting and receiving control channels in a wireless communication system supporting time division multiple access.

3GPP LTE (-A) improves the spectral efficiency of the network so that carriers can provide more data and voice services at a given bandwidth. Therefore, 3GPP LTE (-A) is designed to meet the demand for high-speed data and media transmission in addition to high-capacity voice support. The advantage of LTE is that it can have low throughput with high throughput, low latency, FDD and TDD support on the same platform, improved end user experience and simple architecture.

For more efficient data processing, the dynamic TDD of 3GPP LTE (-A) may use a method of varying the number of OFDM symbols usable for uplink downlink according to the data traffic direction of users of the cell. For example, the base station can allocate a plurality of downlink OFDM symbols to a slot (or a subframe) when downlink traffic of a cell is larger than uplink traffic. Information about the slot configuration should be sent to the user terminals.

3GPP LTE (-A) defines uplink / downlink physical channels for physical layer signal transmission. For example, a physical uplink shared channel (PUSCH) which is a physical channel for transmitting data in the uplink, a physical uplink control channel (PUCCH) for transmitting a control signal, and a physical random access channel (PRACH) A physical downlink shared channel (PDSCH) for transmitting data in downlink, a physical control format indicator channel (PCFICH), a physical downlink control channel (PDCCH), a physical hybrid ARQ indicator channel (PHICH) ).

A downlink control channel (PDCCH / EPDCCH) of the channels is a channel for transmitting uplink / downlink scheduling assignment control information, uplink transmission power control information, and other control information to one or a plurality of terminals. Since there is a limitation on the resources that can be used for the PDCCH / EPDCCH that can be transmitted by the base station at one time, it is not possible to allocate different resources to each terminal, and the control information should be transmitted to any terminal by sharing resources. For example, in 3GPP LTE (-A), four Resource Elements (REs) are grouped together to form REGs (Resource Element Groups), nine CCEs (Control Channel Elements), and one or a plurality of CCEs And informs the UE of a resource, and a plurality of UEs can share the CCE. Here, the number of CCEs to be combined is called CCE coupling level, and the resource to which CCE is allocated according to the possible CCE coupling level is called a search space. The search space may include a common search space defined for each base station and a terminal-specific or UE-specific search space defined for each terminal. The UE performs decoding on the number of possible CCE combining cases in the search space and can determine whether it corresponds to its own PDCCH through a user equipment (UE) identifier included in the PDCCH.

A UE group common PDCCH or a common PDCCH that broadcasts the same information to a plurality of UEs in the DL control channel is allocated and transmitted in a common search space and a PDCCH capable of providing uplink or downlink scheduling information to specific UEs The common search space and the specific-terminal search space. The user terminal performs blind decoding on the common search space and the specific-terminal search space to obtain the downlink control channel information transmitted by the base station. The success or failure of the blind decoding and the method of confirming that the PDCCH is allocated to the UE can be known by viewing the RNTI value indicated in the CRC.

Disclosure of Invention Technical Problem [8] The present invention has been made in order to solve the problems of the related art as described above, and a method for informing a user terminal or a user terminal of a slot configuration whenever a base station changes its uplink downlink configuration.

The objects that can be achieved by the present invention are not limited to those specifically described herein.

According to a first technical aspect of the present invention, there is provided a method of transmitting information on a slot configuration in a wireless communication system using time division multiple access, PDCCH or common PDCCH for transmission; And a PDCCH for notifying information on a slot configuration or scheduling information of the UE to some information.

According to a second technical aspect of the present invention, there is provided a method of receiving information on a slot configuration of a user terminal in a wireless communication system using time division multiple access, blind decoding a common PDCCH or a common PDCCH; Blind decoding of a PDCCH including scheduling information of a specific UE when UE group common PDCCH or common PDCCH fails to receive; And obtaining a slot format or slot configuration information or some information from the specific-terminal PDCCH.

According to a third aspect of the present invention, there is provided a method of configuring slot format or slot configuration information in a PDCCH including scheduling information of a specific UE in a wireless communication system using time division multiple access, A method of repeatedly transmitting information on a slot configuration sent from the UE group common PDCCH or the common PDCCH as it is; How to send information about some slot configurations; A method of sending according to a default slot configuration; And a method of sending in accordance with the operation of the user terminal.

According to a fourth aspect of the present invention, there is provided a method for transmitting a slot format or slot configuration information in a PDCCH including scheduling information of a specific UE in a wireless communication system using a time division multiple access a method of allocating some bits of a group common PDCCH or a common PDCCH, and a method of generating a control information including a UE group common PDCCH or an RNTI according to a slot configuration when generating a common PDCCH.

It will be understood by those skilled in the art that various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the following detailed description of the invention, do.

According to the embodiment of the present invention, the user terminals can know the configuration of the slot used by the base station. Specifically, the base station transmits the information on the slot configuration to the UEs via the UE group common PDCCH or the common PDCCH, so that the UEs can know the configuration of the slot. Since the base station transmits information on the slot configuration or some information to the specific-terminal PDCCH, the terminal decoding the PDCCH can acquire information on the slot configuration or some information. Therefore, even if the user terminal that is assigned the specific-terminal PDCCH fails to receive the UE group common PDCCH or the common PDCCH, it can know the configuration of the slot and the user terminal operation, thereby enabling the uplink transmission or the downlink reception. Through this, the network transmission capacity can be increased.

1 shows an example of a radio frame structure used in a wireless communication system.
2 shows an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system.
3 is a view for explaining a physical channel used in a 3GPP system and a general signal transmission method using the same.
FIG. 4 illustrates a radio frame structure for transmission of a synchronization signal (SS).
5 is a diagram illustrating a structure of a downlink radio frame used in an LTE system.
6 illustrates a configuration of a cell specific common reference signal.
FIG. 7 shows an example of a UL subframe structure used in a wireless communication system.
8 is a conceptual diagram illustrating a carrier aggregation (CA) technique.
FIG. 9 is a diagram for explaining Single Carrier Communication and Multiple Carrier Communication. FIG.
10 is a diagram showing an example in which a cross carrier scheduling technique is applied.
11 is a diagram illustrating a deployment scenario of a UE and a BS in an LTE and LAA service environment.
12 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention.
13 is a diagram of a control region of a PDCCH for control channel transmission in LTE (-A).
Fig. 14- (a) is a diagram of a procedure for transmitting control information in LTE (-A).
FIG. 14- (b) is a diagram for CCE aggregation of PDCCH and multiplexing of PDCCH in LTE (-A).
FIG. 15 is a diagram showing a search space allocation by CCE aggregation for a common search space in the LTE (-A) and a UE specific (or terminal specific) search space.
16 is a diagram showing a slot configuration available in a time division multiple access.
17 is a diagram showing a case where a base station and a user terminal use different slot configurations in a time division multiple access.
18 is a block diagram illustrating a procedure for acquiring slot format or slot configuration information according to an embodiment of the present invention.
19 is a block diagram illustrating a procedure for receiving a PDCCH including a slot format or slot configuration information according to an embodiment of the present invention.
20 is a diagram showing a bandwidth change.
21 is a diagram illustrating a bandwidth change using a slot format or slot configuration information override according to an embodiment of the present invention.
22 is a block diagram illustrating a bandwidth change using a 1-bit slot format or slot configuration information override according to an embodiment of the present invention.

As used herein, terms used in the present invention are selected from general terms that are widely used in the present invention while taking into account the functions of the present invention. However, these terms may vary depending on the intention of a person skilled in the art, custom or the emergence of new technology. Also, in certain cases, there may be a term arbitrarily selected by the applicant, and in this case, the meaning thereof will be described in the description of the corresponding invention. Therefore, it is intended that the terminology used herein should be interpreted relative to the actual meaning of the term, rather than the nomenclature, and its content throughout the specification.

Throughout the specification, when a configuration is referred to as being "connected" to another configuration, it is not limited to the case where it is "directly connected," but also includes "electrically connected" do. Also, when an element is referred to as " including " a specific element, it is meant to include other elements, rather than excluding other elements, unless the context clearly dictates otherwise. In addition, the limitations of " above " or " below ", respectively, based on a specific threshold value may be appropriately replaced with "

FIG. 1 shows an example of a radio frame structure used in a wireless communication system.

Particularly, FIG. 1 (a) shows a frame structure for a frequency division duplex (FDD) used in a 3GPP LTE / LTE-A system and FIG. 1 Time division duplex (TDD) frame structure.

Referring to FIG. 1, a radio frame used in the 3GPP LTE / LTE-A system has a length of 10 ms (307200 Ts) and is composed of 10 equal sized subframes (SF). 10 subframes within one radio frame may be assigned respective numbers. Here, Ts represents the sampling time, and is represented by Ts = 1 / (2048 * 15 kHz). Each subframe is 1 ms long and consists of two slots. 20 slots in one radio frame can be sequentially numbered from 0 to 19. [ Each slot has a length of 0.5 ms. The time for transmitting one subframe is defined as a Transmission Time Interval (TTI). The time resource may be classified by a radio frame number (or a radio frame index), a subframe number (also referred to as a subframe number), a slot number (or a slot index), and the like.

The wireless frame may be configured differently according to the duplex mode. For example, in the FDD mode, since the downlink transmission and the uplink transmission are divided by frequency, the radio frame includes only one of the downlink subframe and the uplink subframe for a specific frequency band. In the TDD mode, since the downlink transmission and the uplink transmission are divided by time, the radio frame includes both the downlink subframe and the uplink subframe for a specific frequency band.

Table 1 illustrates the DL-UL configuration of subframes in a radio frame in TDD mode.

[Table 1]

In Table 1, D denotes a downlink subframe, U denotes an uplink subframe, and S denotes a special subframe. The specific subframe includes three fields of Downlink Pilot Time Slot (DwPTS), Guard Period (GP), and UpPTS (Uplink Pilot Time Slot). DwPTS is a time interval reserved for downlink transmission, and UpPTS is a time interval reserved for uplink transmission. Table 2 illustrates the configuration of the singular frames.

[Table 2]

2 illustrates an example of a downlink (DL) / uplink (UL) slot structure in a wireless communication system. In particular, Figure 2 shows the structure of the resource grid of the 3GPP LTE / LTE-A system. There is one resource grid per antenna port. Referring to FIG. 2, a slot includes a plurality of OFDM symbols in a time domain and a plurality of resource blocks (RB) in a frequency domain. The OFDM symbol also means one symbol period. Referring to FIG. 2, a signal transmitted in each slot may be expressed as a resource grid consisting of N ^{DL / UL} _RB * N ^RB _sc subcarriers and N ^{DL / UL} _symb OFDM symbols. have. Here, N ^DL _RB represents the number of resource blocks (RBs) in the downlink slot, and N ^UL _RB represents the number of _RBs in the UL slot. N ^DL _RB and N ^UL _RB depend on the DL transmission bandwidth and the UL transmission bandwidth, respectively. N ^DL _symb denotes the number of OFDM symbols in the downlink slot, and N ^UL _symb denotes the number of OFDM symbols in the UL slot. N ^RB _sc represents the number of subcarriers constituting one RB. The OFDM symbol may be referred to as an OFDM symbol, an SC-FDM (Single Carrier Frequency Division Multiplexing) symbol, or the like according to a multiple access scheme. The number of OFDM symbols included in one slot can be variously changed according to the channel bandwidth and the length of the cyclic prefix (CP). For example, in the case of a normal CP, one slot includes 7 OFDM symbols

In the case of an extended CP, one slot includes six OFDM symbols. Although FIG. 2 illustrates a subframe in which one slot is composed of seven OFDM symbols for convenience of description, embodiments of the present invention may be applied to subframes having a different number of OFDM symbols in a similar manner. Referring to FIG. 2, each OFDM symbol includes N ^{DL / UL} _RB * N ^RB _sc subcarriers in the frequency domain. The type of subcarrier may be a data subcarrier for data transmission, a reference signal subcarrier for transmission of a reference signal, a null subcarrier for a guard band or a direct current (DC) ≪ / RTI > The DC component is mapped to a carrier frequency (f ₀ ) in an OFDM signal generation process or a frequency up-conversion process. The carrier frequency is also referred to as the center frequency (f _c ).

One RB is defined as N ^{DL / UL} _symb consecutive OFDM symbols in the time domain (for example, seven), and N ^RB _scrambled (e.g., twelve) consecutive subcarriers in the frequency domain . For reference, a resource composed of one OFDM symbol and one subcarrier is referred to as a resource element (RE) or tone. Therefore, one RB consists of N ^{DL / UL} _symb * N ^RB _sc resource elements. Each resource element in the resource grid can be uniquely defined by an index pair (k, 1) in one slot. k is an index assigned from 0 to N ^{DL / UL} _RB * N ^RBsc -1 in the frequency domain, and 1 is an index assigned from 0 to N ^{DL / UL} _symb -1 in the time domain.

One RB is mapped to one physical resource block (PRB) and one virtual resource block (VRB). The PRB is defined as N ^{DL / UL} _symb (e.g., 7) consecutive OFDM symbols or SC-FDM symbols in the time domain, and N ^RB _scrambled (e.g., twelve) Is defined by the subcarrier. Therefore, one PRB consists of N ^{DL / UL} _symb * N ^RB _sc resource elements. Two RBs, one in each of two slots of the subframe occupying N ^RB _sc consecutive identical subcarriers in one subframe, are called a PRB pair. The two RBs constituting the PRB pair have the same PRB number (or PRB index).

In order for the UE to receive a signal from the eNB or to transmit a signal to the eNB, the time / frequency synchronization of the UE should be synchronized with the time / frequency synchronization of the eNB. since it can determine the time and frequency parameters necessary for the UE to perform the demodulation of the DL signal and the transmission of the UL signal at the correct time, as long as it is synchronized with the eNB.

3 is a view for explaining a physical channel used in a 3GPP system and a general signal transmission method using the same.

The terminal performs an initial cell search operation such as synchronizing with a base station when power is increased or newly enters a cell (S301). To this end, the terminal receives a primary synchronization channel (P-SCH) and a secondary synchronization channel (S-SCH) from a base station and synchronizes with the base station and acquires information such as a cell ID have. Then, the terminal can receive the physical broadcast channel from the base station and acquire the in-cell broadcast information. Meanwhile, the UE can receive the downlink reference signal (DL RS) in the initial cell search step to check the downlink channel state.

Upon completion of the initial cell search, the UE receives more detailed system information by receiving a Physical Downlink Control Channel (PDCCH) and a Physical Downlink Control Channel (PDSCH) according to the information on the PDCCH (S302).

On the other hand, if the base station is initially connected or there is no radio resource for signal transmission, the terminal can perform a random access procedure (RACH) on the base station (steps S303 to S306). To this end, the UE transmits a specific sequence through a Physical Random Access Channel (PRACH) (S303 and S305), and receives a response message for the preamble on the PDCCH and the corresponding PDSCH S304 and S306). In case of the contention-based RACH, a contention resolution procedure can be additionally performed.

The UE having performed the procedure described above transmits PDCCH / PDSCH reception (S307) and physical uplink shared channel (PUSCH) / physical uplink control channel Control Channel, PUCCH) (S308). In particular, the UE receives downlink control information (DCI) through the PDCCH. Here, the DCI includes control information such as resource allocation information for the UE, and formats are different according to the purpose of use.

Meanwhile, the control information that the UE transmits to the base station through the uplink or receives from the base station includes a downlink / uplink ACK / NACK signal, a channel quality indicator (CQI), a precoding matrix index (PMI) ) And the like. In the case of the 3GPP LTE system, the UE can transmit control information such as CQI / PMI / RI as described above through PUSCH and / or PUCCH.

FIG. 4 illustrates a radio frame structure for transmission of a synchronization signal (SS). In particular, FIG. 4 illustrates a radio frame structure for transmission of a synchronous signal and a PBCH in a frequency division duplex (FDD). FIG. 4A illustrates a radio frame in a normal CP (normal cyclic prefix) SS and PBCH. FIG. 4 (b) shows transmission positions of SS and PBCH in a radio frame configured with an extended CP.

The UE obtains time and frequency synchronization with the cell when it is powered on or newly connected to the cell, and performs cell search such as detecting the physical cell identity N ^cell _ID of the cell cell search procedure. To this end, the UE receives a synchronization signal, for example, a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the eNB, synchronizes with the eNB, , ID) can be obtained.

Referring to FIG. 4, the SS will be described in more detail as follows. SS is divided into PSS and SSS. PSS is used to obtain time domain synchronization and / or frequency domain synchronization such as OFDM symbol synchronization, slot synchronization, and the like. SSS is used for frame synchronization, cell group ID, and / or cell CP configuration Information). Referring to FIG. 4, the PSS and the SSS are transmitted in two OFDM symbols of each radio frame, respectively. In order to facilitate inter Radio Access Technology ("RAT") measurement, the SS considers 4.6 ms, which is the Global System for Mobile communication (GSM) frame length, in the first slot of subframe 0 and the first slot of subframe 5 Respectively. Specifically, the PSS is transmitted in the last OFDM symbol of the first slot of the subframe 0 and the last OFDM symbol of the first slot of the subframe 5, respectively, and the SSS is transmitted from the second OFDM symbol at the end of the first slot of the subframe 0, Lt; RTI ID = 0.0 > OFDM < / RTI > The boundary of the corresponding radio frame can be detected through the SSS. The PSS is transmitted in the last OFDM symbol of the slot and the SSS is transmitted in the OFDM symbol immediately before the PSS. SS's transmit diversity scheme uses only a single antenna port and is not defined in the standard. That is, a single antenna port transmission or a UE transparent transmission scheme (e.g., Precoding Vector Switching (PVS), Time Switched Diversity (TSTD), Cyclic Delay Diversity (CDD)) can be used for SS transmission diversity .

The SS can represent a total of 504 unique physical layer cell IDs through a combination of three PSSs and 168 SSs. In other words, the physical layer cell IDs are allocated to 168 physical-layer cell-identifier groups, each group including three unique identifiers, such that each physical-layer cell ID is part of only one physical-layer cell- . Thus, the physical layer cell ID _{^{N cell ID = 3N (1)}} ID + N (2) ID is a physical-layer cell - the range of 0 [identifier group to the 167 number N ⁽¹⁾ _ID and the physical-layer cell - a unique number N ⁽²⁾ _ID of 0 to 2 indicating the physical-layer identifier in the identifier group. The UE may detect the PSS to know one of the three unique physical-layer identifiers and may detect the SSS to identify one of the 168 physical layer cell IDs associated with the physical-layer identifier. A ZC (Zadoff-Chu) sequence of length 63 is defined in the frequency domain and used as the PSS.

Referring to FIG. 4, since the PSS is transmitted every 5 ms, the UE can detect that the corresponding subframe is one of the subframe 0 and the subframe 5 by detecting the PSS. However, I do not know what it is. Therefore, the UE can not recognize the boundary of the radio frame only by the PSS. That is, frame synchronization can not be obtained with only PSS. The UE detects an SSS transmitted twice in one radio frame but transmitted as a different sequence and detects the boundary of the radio frame.

5 is a diagram illustrating a control channel included in a control region of one subframe in a downlink radio frame.

Referring to FIG. 5, a subframe is composed of 14 OFDM symbols. According to the subframe setting, the first to third OFDM symbols are used as a control region and the remaining 13 to 11 OFDM symbols are used as a data region. In the figure, R1 to R4 represent a reference signal (RS) or pilot signal for antennas 0 to 3. The RS is fixed in a constant pattern in the subframe regardless of the control region and the data region. The control channel is allocated to a resource to which the RS is not allocated in the control region, and the traffic channel is also allocated to the resource to which the RS is not allocated in the data region. Control channels allocated to the control region include a Physical Control Format Indicator CHannel (PCFICH), a Physical Hybrid-ARQ Indicator CHannel (PHICH), and a Physical Downlink Control Channel (PDCCH).

The PCFICH informs the UE of the number of OFDM symbols used in the PDCCH for each subframe as a physical control format indicator channel. The PCFICH is located in the first OFDM symbol and is set prior to the PHICH and PDCCH. The PCFICH is composed of four REGs (Resource Element Groups), and each REG is distributed in the control area based on the cell ID (Cell IDentity). One REG is composed of four REs (Resource Elements). RE denotes a minimum physical resource defined by one subcarrier x one OFDM symbol. The PCFICH value indicates a value of 1 to 3 or 2 to 4 depending on the bandwidth and is modulated by Quadrature Phase Shift Keying (QPSK).

The PHICH is used as a physical HARQ (Hybrid Automatic Repeat and Request) indicator channel to carry HARQ ACK / NACK for uplink transmission. That is, the PHICH indicates a channel through which DL ACK / NACK information for UL HARQ is transmitted. The PHICH consists of one REG and is cell-specific scrambled. The ACK / NACK is indicated by 1 bit and is modulated by BPSK (Binary Phase Shift Keying). The modulated ACK / NACK is spread with a spreading factor (SF) = 2 or 4. A plurality of PHICHs mapped to the same resource constitute a PHICH group. The number of PHICHs multiplexed into the PHICH group is determined by the number of spreading codes. The PHICH (group) is repetitized three times to obtain the diversity gain in the frequency domain and / or the time domain.

The PDCCH is allocated to the first n OFDM symbols of the subframe as the physical downlink control channel. Here, n is an integer of 1 or more and is indicated by the PCFICH. The PDCCH consists of one or more CCEs. The PDCCH notifies each terminal or group of terminals of information related to resource allocation of a paging channel (PCH) and a downlink-shared channel (DL-SCH), an uplink scheduling grant, and HARQ information. A paging channel (PCH) and a downlink-shared channel (DLSCH) are transmitted on the PDSCH. Therefore, the BS and the MS generally transmit and receive data via the PDSCH, except for specific control information or specific service data.

PDSCH data is transmitted to a terminal (one or a plurality of terminals), and information on how the terminals receive and decode PDSCH data is included in the PDCCH and transmitted. For example, if a particular PDCCH is CRC masked with an RNTI (Radio Network Temporary Identity) of "A ", and a DCI format called " C" Assume that information on data to be transmitted using information (e.g., transport block size, modulation scheme, coding information, etc.) is transmitted through a specific subframe. In this case, the UE in the cell monitors the PDCCH using its RNTI information, and if there is more than one UE having the "A" RNTI, the UEs receive the PDCCH, B "and" C ".

FIG. 6 illustrates the configuration of a cell specific common reference signal. In particular, Figure 6 illustrates a CRS structure for a 3GPP LTE system supporting up to four antennas.

[Equation 1]

Where k is a subcarrier index, 1 is an OFDM symbol index, p is an antenna port number, and ^{Nmax and DL} _RB represent the largest downlink bandwidth configuration, expressed as an integer multiple of N ^RB _sc .

The variables v and v _shift define positions in the frequency domain for different RSs, and v is given by

&Quot; (2) "

Where n _s is the slot number in the radio frame and the cell specific frequency transition is given by:

&Quot; (3) "

Referring to FIG. 6 and Equations 1 and 2, the current 3GPP LTE / LTE-A standard defines a cell-specific CRS used for demodulation and channel measurement among the various RSs defined in the corresponding system, To be transmitted over the entire downlink band. Also, in the 3GPP LTE / LTE-A system, the cell-specific CRS is used for demodulation of the downlink data signal, and thus is transmitted every antenna port for downlink transmission.

Meanwhile, the cell-specific CRS can be used not only for channel state measurement and data demodulation, but also for tracking after the UE acquires time synchronization and frequency synchronization of a carrier used for communication with the UE, It is also used for tracking.

FIG. 7 shows an example of a UL subframe structure used in a wireless communication system.

Referring to FIG. 7, the UL subframe may be divided into a control domain and a data domain in the frequency domain. One or several physical uplink control channels (PUCCHs) may be assigned to the control region to carry uplink control information (UCI). One or several physical uplink shared channels (PUSCHs) may be allocated to the data area of the UL subframe to carry user data.

In the UL subframe, subcarriers far away from each other based on a DC (Direct Current) subcarrier are used as a control region. In other words, the subcarriers located at both ends of the UL transmission bandwidth are allocated for transmission of the UL control information. The DC subcarrier is a component that is left unused for signal transmission and is mapped to the carrier frequency f ₀ in the frequency up conversion process. In one subframe, the PUCCH for one UE is allocated to an RB pair belonging to resources operating at one carrier frequency, and RBs belonging to the RB pair occupy different subcarriers in two slots. The PUCCH allocated as described above is expressed as the RB pair allocated to the PUCCH is frequency hopped at the slot boundary. However, when frequency hopping is not applied, the RB pairs occupy the same subcarrier.

The PUCCH may be used to transmit the following control information.

- SR (Scheduling Request): Information used for requesting uplink UL-SCH resources. OOK (On-Off Keying) method.

- HARQ-ACK: A response to the PDCCH and / or a response to a downlink data packet (eg, codeword) on the PDSCH.

Indicates whether PDCCH or PDSCH has been successfully received. In response to a single downlink codeword, one bit of HARQACK is transmitted and two bits of HARQ-ACK are transmitted in response to two downlink codewords. The HARQ-ACK response includes positive ACK (simply ACK), negative ACK (NACK), DTX (Discontinuous Transmission) or NACK / DTX. Here, the term HARQ-ACK is mixed with HARQ ACK / NACK and ACK / NACK.

- CSI (Channel State Information): Feedback information for the downlink channel. Multiple Input Multiple Output (MIMO) -related feedback information includes RI (Rank Indicator) and PMI (Precoding Matrix Indicator).

Hereinafter, a carrier aggregation technique will be described. 8 is a conceptual diagram illustrating carrier aggregation.

Carrier aggregation is a technique in which a radio communication system uses a frequency block or a (logical sense) cell composed of uplink resources (or component carriers) and / or downlink resources (or component carriers) Which is used as a single large logical frequency band. Hereinafter, the term "component carrier" is used for the convenience of description.

Referring to FIG. 8, the total system bandwidth (System BW) has a bandwidth of 100 MHz as a logical bandwidth. The total system bandwidth includes five component carriers, each of which has a bandwidth of up to 20 MHz. A component carrier comprises one or more contiguous subcarriers physically contiguous. In FIG. 8, each of the component carriers is shown to have the same bandwidth, but this is merely an example, and each component carrier may have a different bandwidth. In addition, although each component carrier is shown as being adjacent to each other in the frequency domain, this figure is shown in a logical concept, wherein each component carrier may physically be adjacent to or spaced from one another.

The center frequency may use different common carriers for each component carrier or common for physically contiguous component carriers. For example, assuming that all of the component carriers are physically adjacent in FIG. 8, the center carrier A can be used. Further, assuming that the respective component carriers are not physically adjacent to each other, the center carrier A, the center carrier B, and the like can be used separately for each component carrier.

In this specification, the component carrier may correspond to the system band of the legacy system. By defining a component carrier based on a legacy system, it is possible to provide backward compatibility and system design in a wireless communication environment in which an evolved terminal and a legacy terminal coexist. In one example, if the LTE-A system supports carrier aggregation, each component carrier may correspond to the system band of the LTE system. In this case, the component carrier may have any of the following bandwidths: 1.25, 2.5, 5, 10, or 20 Mhz.

The frequency band used for communication with each terminal when the entire system band is expanded by carrier aggregation is defined in units of component carriers. Terminal A can use 100 MHz, which is the entire system band, and performs communication using all five component carriers. The terminals B1 to B5 can use only a 20 MHz bandwidth and perform communication using one component carrier. Terminals C ₁ and C ₂ can use a 40 MHz bandwidth and each communicate using two component carriers. The two component carriers may be logically / physically adjacent or non-contiguous. The terminal C ₁ shows a case in which two non-adjacent component carriers are used and the terminal C ₂ shows a case in which two adjacent component carriers are used.

In the LTE system, one downlink component carrier and one uplink component carrier are used, while in the LTE-A system, a plurality of component carriers can be used as shown in FIG. A combination of a downlink component carrier or a corresponding downlink component carrier and a corresponding uplink component carrier may be referred to as a cell and a corresponding relationship between a downlink component carrier and an uplink component carrier may be indicated through system information .

At this time, the scheme of scheduling the data channel by the control channel may be classified into a link carrier scheduling method and a cross carrier scheduling method.

More specifically, link carrier scheduling schedules data channels only through the particular component carrier, such as existing LTE systems that use a single component carrier, over a particular component carrier. That is, the downlink grant / uplink grant transmitted to the PDCCH region of the downlink component carrier of a specific component carrier (or specific cell) can be scheduled only for the PDSCH / PUSCH of the cell to which the corresponding downlink component carrier belongs. That is, the search space, which is an area for attempting to detect the downlink grant / uplink grant, exists in the PDCCH region of the cell where the PDSCH / PUSCH to be scheduled is located.

On the other hand, in the cross carrier scheduling, when a control channel transmitted through a primary component carrier (Primary CC) using a Carrier Indicator Field (CIF) is transmitted through the main component carrier or through another component carrier Schedules the channel. In other words, a monitored cell (Monitored Cell or Monitored CC) of the cross-carrier scheduling is set, and the downlink grant / uplink grant transmitted in the PDCCH region of the monitored cell is set to PDSCH / PUSCH of a cell set to be scheduled in the corresponding cell Scheduling. That is, a search area for a plurality of component carriers is present in a PDCCH area of a cell to be monitored. Among the plurality of cells, system information is transmitted, an initial access attempt is made, and the PCell is set by transmission of uplink control information. The PCell is a downlink main component carrier and an uplink main component carrier corresponding to the downlink main component carrier .

9 is a diagram for explaining single carrier communication and multiple carrier communication. Particularly, FIG. 9A shows a subframe structure of a single carrier and FIG. 9B shows a subframe structure of multiple carriers.

Referring to FIG. 9A, a general wireless communication system performs data transmission or reception (in a frequency division duplex (FDD) mode) through one DL band and one UL band corresponding thereto , A radio frame is divided into an uplink time unit and a downlink time unit in a time domain and data transmission or reception is performed through an uplink / downlink time unit (time division duplex , TDD) mode). However, in recent wireless communication systems, introduction of a carrier aggregation technique using a larger UL / DL bandwidth by collecting a plurality of UL and / or DL frequency blocks in order to use a wider frequency band is being discussed. Carrier aggregation is an orthogonal frequency division multiplexing (OFDM) scheme that performs DL or UL communication by putting a fundamental frequency band divided into a plurality of orthogonal subcarriers on one carrier frequency in that DL or UL communication is performed using a plurality of carrier frequencies division multiplexing system. Hereinafter, each of the carriers collected by carrier aggregation is referred to as a component carrier (CC). Referring to FIG. 9 (b), three 20 MHz CCs can be grouped into UL and DL, respectively, so that a bandwidth of 60 MHz can be supported. Each CC may be adjacent or non-adjacent to one another in the frequency domain. FIG. 9B shows a case where the bandwidth of the UL CC and the bandwidth of the DL CC are the same and symmetric, but the bandwidth of each CC can be determined independently. Asymmetric carrier aggregation in which the number of UL CCs is different from the number of DL CCs is also possible. A DL / UL CC specific to a particular UE may be referred to as a configured serving UL / DL CC in a particular UE.

The eNB may be used to communicate with the UE by activating some or all of the serving CCs configured in the UE, or by deactivating some CCs. The eNB can change the CC to be activated / deactivated, and can change the number of CCs to be activated / deactivated. When the eNB allocates a CC available for the UE in a cell-specific or UE-specific manner, at least one of the assigned CCs is used, as long as the CC allocation for the UE is not completely reconfigured or the UE does not perform a handover. One is not disabled. A CC that is not deactivated is referred to as a primary CC (PCC), and a CC that can be freely activated / deactivated by the eNB is called a secondary CC (SCC), unless it is a full reconfiguration of the CC assignment to the UE It is called. PCC and SCC may be distinguished based on control information. For example, specific control information may be set to be transmitted and received only via a specific CC, which may be referred to as PCC and the remaining CC (s) as SCC (s).

Meanwhile, 3GPP LTE (-A) uses the concept of a cell to manage radio resources. A cell is defined as a combination of DL resources and UL resources, that is, a combination of DL CC and UL CC. A cell may consist of DL resources alone, or a combination of DL resources and UL resources. If carrier aggregation is supported, the linkage between the carrier frequency of the DL resource (or DL CC) and the carrier frequency of the UL resource (or UL CC) . For example, a combination of a DL resource and a UL resource can be indicated by linkage of System Information Block Type 2 (SIB2). Here, the carrier frequency means a center frequency of each cell or CC. In the following,

a cell operating on a frequency is referred to as a primary cell or a PCC and a cell operating on a secondary frequency (or SCC) is referred to as a secondary cell (SCell) It is called. The carrier corresponding to PCell in the downlink is referred to as a downlink primary CC (DL PCC), and the carrier corresponding to PCell in the uplink is referred to as a UL primary CC (DL PCC). SCell refers to a cell that is configurable after a Radio Resource Control (RRC) connection is established and can be used to provide additional radio resources. Depending on the capabilities of the UE, a SCell may form together with the PCell a set of serving cells for the UE. The carrier corresponding to the SCell in the downlink is referred to as DL secondary CC (DL SCC), and the carrier corresponding to the SCell in the uplink is referred to as UL secondary CC (UL SCC)

do. For UEs that are in the RRC_CONNECTED state but no carrier aggregation is set or that do not support carrier aggregation, there is only one serving cell consisting of only PCell.

As previously mentioned, the term cell used in carrier aggregation is distinguished from the term cell, which refers to a geographical area in which a communication service is provided by a single eNB or a group of antennas. In order to distinguish between a cell designating a certain geographical area and a cell of carrier aggregation, a carrier aggregation cell is referred to as a CC and a cell in a geographical area is referred to as a cell. Quot;

In the existing LTE / LTE-A system, when multiple CCs are used together, it is assumed that the UL / DL frame time synchronization of the SCC coincides with the time synchronization of the PCC, assuming that the CCs that are not so far away in the frequency domain are clustered. However, there is a possibility that a plurality of CCs belonging to different frequency bands or spaced apart from each other in frequency, that is, a plurality of CCs having different propagation characteristics, may be gathered in the future. In this case, assuming that the time synchronization of the PCC and the time synchronization of the SCC are the same as in the conventional case, the synchronization of the DL / UL signal of the SCC may be seriously adversely affected.

Meanwhile, in the case of the LCT CC, among the radio resources operating in the LCT CC, radio resources available for transmission / reception of physical uplink / downlink channels and radio resources available for transmission / reception of physical uplink / The resources, as described above, are predetermined. In other words, the LCT CC is not configured to carry physical channels / signals through arbitrary time frequency in arbitrary time resources, but may be configured to transmit the physical channel / Signal should be configured to carry. For example, the physical downlink control channels may be configured only in the first OFDM symbol (s) of the OFDM symbols in the DL subframe, and the PDSCH may include the first OFDM symbol (s) that are likely to be mapped physical downlink control channels. Lt; / RTI > As another example, the CRS (s) corresponding to the antenna port (s) of the eNB are transmitted every subframe in the REs shown in Fig. 6 over the entire band regardless of the DL BW of the eNB. Accordingly, when the number of antenna ports of the eNB is 1, REs indicated by '0' in FIG. 6 are '0', '1', '2' and ' 3 'can not be used for other downlink signal transmission. In addition, there are various constraints on the composition of the LCT CC, and these constraints are greatly increased as the communication system develops. Some of these constraints arise because of the level of communication technology at the time the constraint is created, and there are some constraints that are unnecessary as communication technology develops, and constraints of existing and new technologies for the same purpose It may be present at the same time. As the constraints become so large, the constraints introduced for the development of the communication system are making the wireless resources of the CC ineffective. Therefore, the introduction of NCT CC, which can be constructed according to the simplified constraints rather than the existing constraints, is free from the constraints that are unnecessary according to the development of the communication technology. Since the NCT CC is not constructed according to the constraints of the existing system, it can not be recognized by the UE implemented according to the existing system. Hereinafter, UEs which are implemented according to the existing system and can not support NCT CC are called legacy UEs, and UEs implemented to support NCT CCs are called NCT UEs.

It is considered that NCT CC will be used as SCC in LTE-A system in the future. Since the NCT CC does not consider use by the legacy UE, the legacy UE does not need to perform cell search, cell selection, cell reselection, etc. in the NCT CC. If the NCT CC is not used as a PCC and the NCT CC is used only as an SCC, unnecessary constraints on the SCC can be reduced compared to an existing LCT CC that can be used as a PCC, enabling more efficient use of the CC. However, the time / frequency synchronization of the NCT CC may not coincide with the synchronization of the PCC. Even if the time / frequency synchronization of the NCT CC is obtained once, the time / frequency synchronization may be changed according to the change of the communication environment. An RS in which time synchronization and / or frequency synchronization can be used for tracking is required. An RS is also needed to allow the UE to detect the NCT CC in the neighbor cell search process. CRS can be used for purposes such as time / frequency synchronization of NCT CC and neighbor cell search using NCT CC. The CRS may be configured in the NCT CC in the same manner as in the existing LTE / LTE-A system shown in FIG. 6 and may have a smaller density in the time axis or frequency axis than the existing LTE / LTE- It may be configured in the NCT CC.

In the present invention, it is proposed that the CRS on the NCT CC is configured to have a lower density on the time axis than the CRS on the LCT CC of the existing LTE / LTE-A system. Accordingly, in the present invention, the NCT CC includes a constraint condition that the CRS is configured in the corresponding CC for every DL subframe, a constraint condition that the CRS is configured in the CC for each antenna port of the eNB, a predetermined number of OFDM It may not satisfy at least one of the constraint conditions that the symbol should be reserved for transmission of the control channel such as the PDCCH over the frequency band of the corresponding CC. For example, on the NCT CC, a CRS may be configured for every predetermined number (> 1) of subframes, not every subframe. Or, on the NCT CC, only the CRS for one antenna port (e.g., antenna port 0) can be configured regardless of the number of antenna ports of the eNB. The CRS of the present invention may not be used for data demodulation unlike the existing CRS shown in FIG. Therefore, instead of the existing CRS used for channel state measurement and demodulation, a tracking RS is newly defined for tracking of time synchronization and / or frequency synchronization, and the tracking RS is added to some subframes and / or some frequency resources on the NCT CC Lt; / RTI > Alternatively, the PDSCH may be configured in the leading OFDM symbols on the NCT CC, the PDCCH may be configured in the existing PDSCH region other than the initial OFDM symbols, or the PDCCH may be configured using some frequency resources. Hereinafter, unlike the existing LTE / LTE-A system, unlike the existing LTE / LTE-A system, the RSs transmitted in some subframes can be used in common by any UE regardless of the name, such as time synchronization and / or frequency synchronization of the NCT CC, RS (common RS, CRS).

10 is a diagram showing an example in which a cross carrier scheduling technique is applied. In particular, in FIG. 10, the number of allocated cells (or component carriers or component carriers) is three and the cross carrier scheduling technique is performed using CIF as described above. Here, it is assumed that the downlink cell # 0 is a downlink main component carrier (i.e., a primary cell, PCell) and the remaining component carriers # 1 and # 2 are subsidiary components (i.e., a secondary cell, SCell).

In the present invention, an effective management method of uplink resources for a main component carrier (primary component carrier, primary cell or PCell) or a subsidiary component carrier (secondary component carrier or secondary cell or SCell) during a carrier aggregation operation I suggest. Hereinafter, the case where the terminal operates by merging two component carriers is explained, but it is obvious that the present invention can also be applied to the case of merging three or more component carriers.

11 is a diagram illustrating a deployment scenario of a UE and a BS in an LTE and LAA service environment.

In the frequency band targeted by the LAA service environment, the wireless communication distance is not long due to the high frequency characteristics. In consideration of this, the deployment scenario between the terminal and the base station in the environment where the existing LTE-licensed service and the LAA service coexist is the overlay model shown on the left side of FIG. 11 and the overlay model shown in the right side of FIG. or a co-located model.

In the case of the overlay model shown in the left side of FIG. 11, the macro eNB performs wireless communication with the X terminal and the X 'terminal in the macro area 32 using a licensed carrier, and a plurality of RRHs and an X2 interface Lt; / RTI > Each RRH may perform wireless communication with an X terminal or an X 'terminal in a certain area 31 using an unlicensed carrier. In this case, there is no mutual interference between the macro eNB and the RRH. However, in order to use the LAA service as an auxiliary downlink channel of the LTE-licensed service through carrier aggregation, an X2 interface between the macro eNB and the RRH A fast data exchange should be made.

In the case of the co-located model shown on the right-hand side of FIG. 11, the pico / femto eNB can perform wireless communication with the Y terminal simultaneously using an authorized carrier and an unauthorized carrier. However, the use of the LTE service and the LAA service together is considered in the downlink data transmission. In this case, coverage for LTE service and coverage for LAA service may differ depending on frequency band, transmission power, and the like.

A terminal according to an embodiment of the present invention can be implemented by various types of wireless communication devices or computing devices that are guaranteed to be portable and mobility.

The base station according to the embodiment of the present invention controls and manages a cell (for example, a macro cell, a femtocell, a picocell, etc.) corresponding to a service area and transmits a signal, channel designation, channel monitoring, Can be performed.

12 is a block diagram showing the configuration of a terminal and a base station according to an embodiment of the present invention.

As shown, a terminal 100 according to an embodiment of the present invention may include a processor 110, a communication module 120, a memory 130, a user interface unit 140, and a display unit 150 have.

First, the processor 110 may execute various commands or programs, and may process data inside the terminal 100. [ In addition, the processor 100 can control the entire operation including each unit of the terminal 100, and can control data transmission / reception between the units.

Next, the communication module 120 may be an integrated module that performs wireless communication using a wireless communication network and wireless LAN connection using a wireless LAN. To this end, the communication module 120 may include a plurality of network interface cards such as the cellular communication interface cards 121 and 122 and the wireless LAN interface card 123, either internally or externally. 12, the communication module 120 is shown as an integrated integrated module, but each network interface card may be independently arranged according to the circuit configuration or use, unlike in FIG.

The cellular communication interface card 121 according to the first frequency band transmits and receives a radio signal with at least one of the base station 200, the external device, and the server using the mobile communication network, Band cellular communication service. Here, the wireless signal may include various types of data or information such as a voice call signal, a video call signal, or a text / multimedia message.

According to an embodiment of the present invention, the cellular communication interface card 121 by the first frequency band may include at least one NIC module using the LTE-Licensed frequency band. According to an embodiment of the present invention, at least one NIC module performs cellular communication with at least one of the base station 200, the external device, and the server independently in accordance with the cellular communication standard or protocol of the frequency band supported by the corresponding NIC module . The cellular communication interface card 121 may operate only one NIC module at a time or may operate a plurality of NIC modules at the same time according to the performance and requirements of the terminal 100. [

The cellular communication interface card 122 in the second frequency band transmits and receives a radio signal to and from a base station 200, an external device, and a server using a mobile communication network, Band cellular communication service. According to an embodiment of the present invention, the cellular communication interface card 122 by the second frequency band may include at least one NIC module using the LTE-Unlicensed frequency band. For example, the LTE-Unlicensed frequency band may be a band of 2.4 GHz or 5 GHz. According to an embodiment of the present invention, at least one NIC module performs cellular communication with at least one of the base station 200, the external device, and the server independently in accordance with the cellular communication standard or protocol of the frequency band supported by the corresponding NIC module . The cellular communication interface card 122 may operate only one NIC module at a time or may operate a plurality of NIC modules at the same time according to the performance and requirements of the terminal 100. [

The wireless LAN interface card 123 according to the second frequency band transmits and receives a radio signal to at least one of the base station 200, the external device, and the server through the wireless LAN connection, Band wireless LAN service. According to an embodiment of the present invention, the wireless LAN interface card 123 according to the second frequency band may include at least one NIC module using the wireless LAN frequency band. For example, the WLAN frequency band may be an unlicensed radio band such as a band of 2.4 GHz or 5 GHz. According to an embodiment of the present invention, at least one NIC module performs wireless communication with at least one of the base station 200, the external device, and the server independently in accordance with a wireless LAN standard or protocol of a frequency band supported by the corresponding NIC module . The wireless LAN interface card 123 may operate only one NIC module at a time or may operate a plurality of NIC modules at the same time according to the performance and requirements of the terminal 100. [

According to an embodiment of the present invention, the processor 110 transmits information on whether or not the wireless LAN communication service of the second frequency band is available through the cellular communication channel of the first frequency band with the base station 200, Information on the period of time. Here, the information on the predetermined period is information set for receiving the downlink data from the base station 200 through the cellular communication channel of the second frequency band.

In addition, according to an embodiment of the present invention, since the base station 200 supports a wireless LAN communication service, the processor 110 can receive a predetermined signal from the base station 200 through a wireless LAN communication channel of a second frequency band And receives the base station coexistence message including information on the period.

In addition, according to an embodiment of the present invention, the processor 110 may be configured to transmit, in response to the received base station coexistence message, The terminal transmits a terminal coexistence message including information on a predetermined period according to a standard or protocol specified in the wireless LAN communication service of the second frequency band.

Also, according to an embodiment of the present invention, the processor 110 receives downlink data from the base station 200 for a predetermined period through a cellular communication channel of a second frequency band.

Next, the memory 130 stores a control program used in the terminal 100 and various data corresponding thereto. The control program may include a predetermined program required for the terminal 100 to perform wireless communication with at least one of the base station 200, the external device, and the server.

Next, the user interface 140 includes various types of input / output means provided in the terminal 100. That is, the user interface 140 can receive user input using various input means, and the processor 110 can control the terminal 100 based on the received user input. In addition, the user interface 140 may perform output based on instructions of the processor 110 using various output means.

Next, the display unit 150 outputs various images on the display screen. The display unit 150 may output various display objects such as a content executed by the processor 110 or a user interface based on a control command of the processor 110. [

12, the base station 200 according to an exemplary embodiment of the present invention may include a processor 210, a communication module 220, and a memory 230. In addition,

First, the processor 210 may execute various commands or programs and may process data within the base station 200. In addition, the processor 210 can control the entire operation including each unit of the base station 200, and can control data transmission / reception between the units.

Next, the communication module 220 may be an integrated module for performing mobile communication using a mobile communication network and wireless LAN connection using a wireless LAN, such as the communication module 120 of the terminal 100 described above. To this end, the communication module 120 may include a plurality of network interface cards, such as the cellular communication interface cards 221 and 222 and the wireless LAN interface card 223, either internally or externally. 12, the communication module 220 is shown as an integrated integration module, but each network interface card may be independently arranged according to the circuit configuration or use, unlike in FIG.

The cellular communication interface card 221 according to the first frequency band transmits and receives a radio signal to at least one of the terminal 100, the external device, and the server using the mobile communication network, And provides cellular communication service by one frequency band. Here, the wireless signal may include various types of data or information such as a voice call signal, a video call signal, or a text / multimedia message.

According to an embodiment of the present invention, the cellular communication interface card 221 by the first frequency band may include at least one NIC module using the LTE-Licensed frequency band. According to an embodiment of the present invention, the at least one NIC module can perform cellular communication with at least one of the terminal 100, the external device, and the server independently according to the cellular communication standard or protocol of the frequency band supported by the corresponding NIC module. Can be performed. The cellular communication interface card 221 may operate only one NIC module at a time or may operate a plurality of NIC modules at the same time according to the performance and requirements of the base station 200.

The cellular communication interface card 222 according to the second frequency band transmits and receives a radio signal to at least one of the terminal 100, the external device, and the server using the mobile communication network, And provides a cellular communication service by two frequency bands. According to an embodiment of the present invention, the cellular communication interface card 222 by the second frequency band may include at least one NIC module using the LTE-Unlicensed frequency band. For example, the LTE-Unlicensed frequency band may be a band of 2.4 GHz or 5 GHz. According to an embodiment of the present invention, the at least one NIC module can perform cellular communication with at least one of the terminal 100, the external device, and the server independently according to the cellular communication standard or protocol of the frequency band supported by the corresponding NIC module. Can be performed. The cellular communication interface card 222 may operate only one NIC module at a time or may operate a plurality of NIC modules at the same time according to the performance and requirements of the base station 200. [

The wireless LAN interface card 223 according to the second frequency band transmits and receives a wireless signal to at least one of the terminal 100, the external device, and the server through the wireless LAN connection, 2 frequency band. According to an embodiment of the present invention, the wireless LAN interface card 223 according to the second frequency band may include at least one NIC module using the wireless LAN frequency band. For example, the WLAN frequency band may be an unlicensed radio band such as a band of 2.4 GHz or 5 GHz. According to an embodiment of the present invention, at least one NIC module independently communicates with at least one of the terminal 100, the external device, and the server in accordance with a wireless LAN standard or protocol of a frequency band supported by the corresponding NIC module Can be performed. The wireless LAN interface card 223 can operate only one NIC module at a time or operate a plurality of NIC modules at the same time according to the performance and requirements of the base station 200. [

According to an embodiment of the present invention, the processor 210 transmits information on whether or not the wireless LAN communication service of the second frequency band is available through the cellular communication channel of the first frequency band with the terminal 100, Information on the period of time. Here, the information on the predetermined period is information set for transmitting the downlink data to the terminal 100 through the cellular communication channel of the second frequency band.

In addition, according to an embodiment of the present invention, the processor 210 may be a peripheral terminal capable of communicating with the base station 200 through the terminal 100 and the wireless LAN communication service of the second frequency band, And transmits the base station coexistence message including information on a predetermined period according to a standard or protocol defined in the wireless LAN communication service to the terminal 100 for a predetermined period on the cellular communication channel of the second frequency band, .

In addition, according to an embodiment of the present invention, since the terminal 100 supports the wireless LAN communication service, the processor 210 transmits the base station coexistence message Lt; RTI ID = 0.0 > coexistence < / RTI > Here, the terminal coexistence message includes information on a predetermined period.

The terminal 100 and the base station 200 shown in FIG. 12 are block diagrams according to an embodiment of the present invention. Blocks that are separately displayed are logically distinguished from elements of a device. Thus, the elements of the device described above can be mounted as one chip or as a plurality of chips depending on the design of the device. In addition, in the embodiment of the present invention, some components of the terminal 100, such as the user interface 140 and the display unit 150, may be optionally provided in the terminal 100. In addition, in the embodiment of the present invention, the user interface 140, the display unit 150, and the like may be additionally provided to the base station 200 as needed.

FIG. 13 shows a control region in which a PDCCH is transmitted in an LTE (-A) system. The control resign may be composed of 1 to 3 OFDM symbols (s) and may extend to 4 OFDM symbols when the system BW is 1.4 MHz. The PDCCH of the control region can be transmitted over 1 to 3 OFDM symbols (s) according to the size of the control region. And the PDCCH may be transmitted over the frequency axis or time axis within the control region.

Fig. 14- (a) relates to a procedure for control information and control channel transmission in LTE (-A). Each control information is subjected to rate matching according to the amount of resources (s) used for PDCCH transmission after attaching CRC according to the RNTI value according to the purpose and tailed biting convolutional coding. The PDCCHs (s) to be transmitted in a given subframe are multiplexed with PDCCHs using the CCE-based PDCCH structure to map resources to be transmitted. The number of CCEs used for one PDCCH is defined as the aggregation level. In LTE (-A), 1, 2, 4, and 8 can be used. FIG. 14- (b) is a diagram of CCE aggregation and multiplexing of a PDCCH, and shows a type of a CCE aggregation level used for one PDCCH and a CCE (s) transmitted in the corresponding control region.

15 is a diagram for setting up a PDCCH search space in the LTE (-A) system. In order to transmit the PDCCH to the UE, at least one search space per UE may exist in the control region. In the present invention, the search space refers to all the time-space resource combinations to which the PDCCH of the UE can be transmitted, and includes a common search space common to all terminals of 3GPP LTE (-A) Specific or UE-specific search space to which a specific UE must search. The common search space is set to monitor a PDCCH that is set so that all terminals in a cell belonging to the same base station are commonly found. A specific terminal search space is defined as a PDCCH allocated to each terminal in search space positions However, the search space between the UEs may be partially overlapped due to the limited control region to which the PDCCH can be allocated.

For convenience of description of the present invention, a PDCCH scrambled with a group common RNTI (or common control RNTI, CC-RNTI) already known by the user terminals is transmitted as a UE group common PDCCH or a common PDCCH And describes a PDCCH scrambled with a specific UE RNTI that the UE has already known to be a specific UE PDCCH in order to transmit uplink scheduling information or downlink scheduling information to one specific UE. RNTIs, P-RNTIs, RA-RNTIs, TPC-RNTIs, etc. may be used as RNTIs used by one or more user terminals in LTE (-A). There may be C-RNTI, SPS C-RNTI, etc. in the specific-terminal RNTI.

16 is a diagram showing how one slot of a mobile communication system using TDD is configured. One slot may be composed of 7 OFDM symbols, and a gap (GP) of one OFDM symbol length may exist when the downlink-uplink is changed. In addition, one OFDM symbol may be used to convey DL control information. 16, it is possible to have eight slot configurations. The slot configuration 0 is a slot composed of downlink OFDM symbols. The slot configuration 1 is a slot composed of six downlink OFDM symbols and one GP. The slot configuration 2 is a slot composed of five downlink OFDM symbols, one GP, and one uplink OFDM symbol. The slot configuration 3 is a slot composed of four downlink OFDM symbols, one GP, and two uplink OFDM symbols. The slot configuration 4 is a slot composed of three OFDM symbols, one GP, and three uplink OFDM symbols. The slot configuration 5 is a slot composed of two OFDM symbols, one GP, and four uplink OFDM symbols. The slot configuration 6 is a slot composed of one OFDM symbol, one GP, and five uplink OFDM symbols. The slot configuration 7 is a slot composed of 7 uplink OFDM symbols.

Referring to FIGS. 15 and 16, the base station can change the slot format or slot configuration, and can transmit the changed slot format or slot configuration information to the UE group common PDCCH, the UE group common PDCCH, or the common PDCCH. The user terminal can find the slot format or slot configuration information from the UE group common PDCCH or the UE group common PDCCH or the common PDCCH transmitted from the base station and transmit / receive according to the slot format or slot configuration information found. The slot format or slot configuration information to be transmitted may convey the configuration of the current slot in which the UE group common PDCCH or the common PDCCH is transmitted. In addition, the slot format or slot configuration information to be transmitted may include not only the configuration of the current slot in which the common PDCCH is transmitted but also information on the configuration of the next slot (s) at a time, or the configuration of the current slot may have the same configuration Or transmit the configuration information of the current slot and the next slot. In this patent, for convenience of description, only the situation of transmitting the current slot configuration is handled, but the present invention can be used even in a situation where several future slot configurations can be transmitted at a time.

In an embodiment, to inform the slot configuration in FIG. 16, the UE group may be notified by including one of 8 DL / UL configurations in the UE group common PDCCH or the common PDCCH, It can be informed by including the time point at which the downlink ends. Since the downlink is ended in the seventh OFDM symbol, slot configuration 0 can be represented by 111, which is 3-bit information. Since the downlink is completed in the sixth OFDM symbol, slot configuration 1 can be represented by 110, which is 3-bit information. In the same manner, since the downlink is completed in the first OFDM symbol, the slot configuration 6 can be represented by 001, which is 3-bit information. Finally, since the slot configuration 7 has no downlink OFDM symbol, the 3-bit information, 000, can be represented. In order to inform the configuration of the slot, it is informed by including one of the 8 DL / UL configurations through the DCI transmitted through the UE specific PDCCH or the UE specific PDCCH rather than the common PDCCH or commom PDCCH, Or by including the point at which the downlink ends.

FIG. 17 shows a situation that may occur when a slot configuration used by a base station is different from a slot configuration used by a user terminal. 17, the actual slot format is the configuration of the slot actually used by the base station, and the UE decision is the configuration of the slot recognized by the terminal. As described above, the base station can transmit the UE group common PDCCH or the common PDCCH to notify the terminal (s) of the slot configuration. However, a specific user terminal may fail to receive the UE group common PDCCH or common PDCCH transmitted from the base station. When the UE fails to receive the UE group common PDCCH or the common PDCCH, the UE can not know whether the UE has transmitted the UE group common PDCCH or the common PDCCH to inform the changed slot configuration. Therefore, the terminal can operate with a slot configuration that the base station is expected to use. For example, the base station may inform a user terminal of a predetermined default slot configuration, and when the user terminal fails to receive the UE group common PDCCH or the common PDCCH, performs uplink transmission or downlink reception using the default slot configuration can do.

Referring to FIG. 17 (a), when the base station uses slot configuration 2 and the user terminal uses slot configuration 0, the user terminal scheduled for downlink determines that all slots are downlink OFDM symbols, Symbol is regarded as a downlink symbol and received. Accordingly, since the user terminal receives two OFDM symbols that are not allocated in the downlink, the probability of decoding failure increases and the user terminal wastes energy. In addition, if a LLR (Log Likelihood Ratio) value corresponding to two OFDM symbols not allocated to the downlink is stored in the soft buffer, performance deterioration may occur during retransmission. In addition to the above problem, resource consumption for downlink retransmission may occur. Referring to FIG. 17 (b), when the base station uses slot configuration 4 and the user terminal uses slot configuration 5, the user terminal scheduled in the uplink starts uplink transmission starting from the fourth OFDM symbol. According to the slot configuration of the base station, since the uplink transmission is performed from the 5th OFDM symbol, it is difficult for the base station to receive the uplink signal due to the uplink transmission of the erroneous user terminal. In addition, since the base station transmits an erroneous uplink signal to the GP to prevent downlink-uplink interference due to a transmission delay, interference may occur to neighboring user terminals that receive the downlink, degrading downlink reception performance.

In order to solve the above-described problem, if the UE does not successfully receive the slot format or the slot configuration information transmitted from the UE group common PDCCH or the common PDCCH, the UE transmits the scheduled uplink symbol It may not perform the downlink symbol, or may not receive the downlink symbol scheduled, or both the uplink transmission and the downlink reception. If the user does not receive the downlink symbol scheduled for the downlink, the base station can transmit information again through HARQ (Hybrid ARQ) retransmission. When the user does not transmit the uplink symbol scheduled in the uplink, the base station may transmit uplink scheduling information again so that the uplink transmission may be performed by the terminal. However, since the above-mentioned scheme does not use the resources allocated in the scheduled slots, resource waste occurs and an additional delay time occurs because a retransmission or re-scheduling scheme is required.

In another embodiment, the base station and the UE can define a default slot format to be used in advance, and upon successful reception of the slot format or slot configuration information transmitted on the UE group common PDCCH or the common PDCCH, And can perform uplink transmission or downlink reception according to the default slot format when it can not successfully receive the slot format or slot configuration information transmitted from the UE group common PDCCH or the common PDCCH.

In another embodiment, when the format of a slot or the configuration information of a slot is to be changed, the base station is set to transmit a UE group common PDCCH or a common PDCCH to a UE in a continuous slot or periodically with a UE group common PDCCH or a common PDCCH It is possible to resolve the ambiguity between the base station and the terminal with respect to the slot format and the configuration information of the terminal and the base station by transmitting the information continuously and periodically. When the UE continuously receives the UE group common PDCCH or the common PDCCH regarding the format of the slot or the change of the configuration information of the slot from the base station

- The base station can perform downlink transmission or uplink reception using the configuration information of the changed slot from the next slot of the slot continuously receiving the UE group common PDCCH or the common PDCCH, It is possible to perform downlink reception and uplink transmission in the terminal based on the configuration information.

- The base station performs the downlink transmission or the uplink reception using the changed slot configuration information from the start of the slot of the next period in which the UE group common PDCCH or the common PDCCH is continuously received in the periodic transmission interval set periodically And the UE can perform downlink reception and uplink transmission in the UE based on the configuration information of the changed slot.

- The base station can perform downlink transmission or uplink reception using the configuration information of the changed slot from the start of the slot continuously receiving the UE group common PDCCH or the common PDCCH, It is possible to perform downlink reception and uplink transmission in the terminal.

When receiving a UE group common PDCCH or common PDCCH related to the change of configuration information of a slot in two consecutive slots or slots of consecutive periods, when one is received and the other is not received, for example, 2) In case of receiving the UE group common PDCCH or common PDCCH in the slot of the previous slot and the UE group common PDCCH or the common PDCCH in the lag slot, PDCCH or the common PDCCH and in the trailing slot, the UE does not receive the common PDCCH or the common PDCCH, the UE can use the configuration information of the slot indicated in the common PDCCH or common PDCCH . 1) and 2), it is assumed that the terminal has failed in reception for changing the slot format and the slot configuration information from the base station, and the terminal does not perform the slot format and the slot configuration information change, And to perform scheduled downlink reception or uplink transmission using the slot configuration information. Or, in case of 1) and 2), a UE group common PDCCH or a common PDCCH related to the change of slot format or slot configuration information is continuously received from the base station based on the slot received the UE group common PDCCH or common PDCCH The downlink reception and the uplink transmission of the UE can be performed in the following three ways.

- The UE can perform downlink transmission or uplink reception using the configuration information of the changed slot from the next slot of the slot that has received the UE group common PDCCH or the common PDCCH, It is possible to perform downlink reception and uplink transmission in the terminal.

- The base station can perform the downlink transmission or the uplink reception using the changed slot configuration information from the beginning of the slot of the next cycle after receiving the UE group common PDCCH or the common PDCCH in the periodic transmission interval set periodically , The UE can perform downlink reception and uplink transmission in the UE based on the configuration information of the changed slot.

The base station can perform downlink transmission or uplink reception using the configuration information of the changed slot from the start of the slot in which the UE group common PDCCH or the common PDCCH is received, Thereby performing downlink reception and uplink transmission in the terminal.

On the PDCCH  How to Tell

18, a slot format or slot configuration information is added to a UE-specific PDCCH for a specific-terminal capable of transmitting scheduling information to a specific user terminal, with reference to FIG. 18 for solving the above- . A slot format or slot configuration information may be inserted and transmitted in order to transmit a slot format or slot configuration information together with downlink or uplink scheduling information to the specific-terminal PDCCH. 16, 3 bits can be considered as a bit size for informing a slot format composed of DL and UL. However, the format of the slot may not be limited to the configuration of only DL and UL, and DL, UL, the bit size may be determined depending on the slot format or the number of the slot configuration information even in this case because there may be a configuration of 'any', 'sidelink', 'blank' Referring to FIG. 18, the user terminal (s) that have successfully received the UE group common PDCCH or the common PDCCH through the CRC check of the UE group common PDCCH or the common PDCCH are informed of the slot format or slot configuration information (For example, 3-bit information) may not be used. If the user terminal that fails to receive the UE group common PDCCH or the common PDCCH through the CRC check of the UE group common PDCCH or the common PDCCH succeeds in CRC check of the specific-terminal PDCCH, the slot format or slot configuration information (For example, 3 bits), the uplink / downlink / GP configuration of the slot can be known, and uplink transmission and downlink reception can be performed based on the information. Also, a specific user terminal can know the slot configuration by receiving only the specific-terminal PDCCH without receiving the UE group common PDCCH or the common PDCCH.

In an exemplary embodiment of the present invention, a slot format or slot configuration information for transmitting information on a slot configuration in a specific-terminal PDCCH to which uplink or downlink scheduling information is transmitted may be a number of slot configurations ≪ / RTI > More specifically, the slot format or slot configuration information transmitted on the specific-terminal PDCCH may be the same as the slot configuration information transmitted on the UE group common PDCCH or the common PDCCH. 16, slot format or slot configuration information transmitted from the UE group common PDCCH or the common PDCCH and the slot format or slot configuration information transmitted from the specific-terminal PDCCH may be transmitted in the same manner . The slot format or slot configuration information transmitted in the specific-terminal PDCCH described above may be transmitted in a number less than the number of cases that can be transmitted in the UE group common PDCCH or the common PDCCH. For example, it is possible to transmit a specific 4 out of possible 8 slot configurations 0 to 7 by 2 bits.

In one embodiment of the present invention, a slot format or slot configuration information for transmitting information on a slot configuration in a specific-terminal PDCCH to which downlink scheduling information is transmitted can indicate the end of a downlink OFDM symbol in a slot. For example, when the base station uses slot configuration 5, it can inform that the downlink is transmitted up to the second OFDM symbol. A UE scheduled in the downlink can know the end point of the downlink OFDM symbol from the slot format or the slot configuration information (for example, 3 bits) and can receive the downlink using the information. Also, the UE scheduled in the uplink can know the end point of the downlink OFDM symbol from the slot format or the slot configuration information, and can know the start point of the uplink OFDM symbol according to the GP configuration.

In one embodiment of the present invention, a slot format or slot configuration information for transmitting information on a slot configuration in a specific-terminal PDCCH to which uplink scheduling information is transmitted may indicate a position where an uplink OFDM symbol starts in a slot . For example, when slot configuration 5 is used, it can be informed that the uplink transmission starts from the fourth OFDM symbol. A UE scheduled in the uplink can know the starting point of the uplink OFDM symbol from the slot format or slot configuration information, and can use the information for uplink transmission. Also, the UE scheduled in the downlink can know the starting point of the uplink OFDM symbol from the slot format or the slot configuration information, and can know the end point of the downlink OFDM symbol according to the GP configuration.

When the base station and the terminal know the default slot configuration, in one embodiment of the present invention, the slot format or slot configuration information described above can be informed by 1 bit whether the slot configuration used by the base station is the same as the default slot configuration . If the slot format or slot configuration information is 0, the slot configuration used by the base station is the same as the default slot configuration, and if the slot format or slot configuration information is 1, the slot configuration used by the base station is different from the default slot configuration. The user terminal can determine whether to perform an operation according to the information scheduled in the specific-terminal PDCCH according to the slot format or the slot configuration information. If the slot format or the slot configuration information is 0, the user terminal can transmit in the default slot configuration because the slot configuration used by the base station is the same as the default slot configuration. If the slot format or the slot configuration information is 1, the user terminal may not perform the scheduled uplink or downlink transmission because the slot configuration used by the base station is different from the default slot configuration.

When the base station and the terminal know the default slot configuration, in an embodiment of the present invention, the described slot format or slot configuration information may be determined according to the default slot configuration. For example, when the slot format for the slot configuration i in the default slot configuration and the slot configuration information for informing four different slot configurations in the specific-terminal PDCCH is 2 bits, 00 indicates the default slot format and the configuration information i as 01 is a different slot format and slot configuration information, i + j _1, 10 has a different slot format and slot configuration information, i + j _2, 11 may use a different slot format and slot configuration information i j + _3. In the above description, j ₁ , j ₂ , and j ₃ may be determined in advance by the base station according to the default slot format and configuration information to inform different slot formats and configuration information. That is, it informs four different slot format information, one of which can be set to be the same as the default slot format (bit 00). The user terminal can perform uplink transmission or downlink reception scheduled in the specific-terminal PDCCH using the default slot information, slot format or slot configuration information. As another example, it is possible to consider a method of specifying an increase or a decrease in the number of symbols of DL or UL, as opposed to informing slot format and slot configuration information. For example, if the default slot format is DL (a) / GP (1) / UP (6-a) ), The base station can have four options as a 1 increase / 2 increase / 1 decrease / a, and by transmitting these options in 2 bits, the DL / UL can be flexibly changed without changing the predetermined slot format and configuration information. A method of changing the number may be considered.

When the base station and the terminal know the default slot configuration, in an embodiment of the present invention, the described slot format or slot configuration information may be determined according to the operation of the user terminal informing on the specific-terminal PDCCH and the default slot configuration . For example, according to the scheduling information given to the UE, the UE can indicate whether it can receive the downlink or transmit the uplink in the default slot configuration. More specifically, when the 1-bit slot format or slot configuration information indicated in the specific-terminal PDCCH is set to 0, the terminal receives the downlink according to the scheduling information of the specific-terminal PDCCH on the assumption of the default slot configuration, When the 1-bit slot format or the slot configuration information is set to 1, the downlink is received regardless of the scheduling information of the specific-terminal PDCCH or the uplink transmission operation is performed.

Referring to FIG. 16, when the default slot configuration is 4 and the base station uses slot configuration 5, the uplink scheduled user terminal can transmit on the uplink using the 5th, 6th, and 7th OFDM symbols. In this case, the base station allocates the OFDM symbol 4 as the uplink, but the user terminal can use the GP. Accordingly, in this case, the 1-bit slot format or the slot configuration information is set to 0 to enable the UE to perform uplink transmission, and the base station can receive the uplink from the UE. However, when the default slot configuration is 4 and the base station uses slot configuration 3, the user scheduled in the uplink may not be able to transmit in the default slot configuration. Therefore, in this case, the 1-bit slot format or slot configuration information may be set to 1 so that the terminal does not perform transmission on the uplink. Referring to FIG. 16, when the default slot configuration is 4 and the base station uses slot configuration 3, the downlink-scheduled user terminal can receive the downlink using the second and third OFDM symbols. In this case, the BS allocates the fourth OFDM symbol as a downlink, but the MS can ignore the fourth OFDM symbol. Therefore, in this case, the 1-bit slot format or the slot configuration information is set to 0 so that the terminal performs reception on the downlink, and the terminal can receive the corresponding downlink from the base station. However, when the default slot configuration is 4 and the base station uses slot configuration 5, the downlink-scheduled user terminals may not be able to receive downlinks. In this case, the 1-bit slot format or slot configuration information may be set to 1 so that the terminal does not perform downlink reception.

When the base station and the terminal know the default slot configuration, in one embodiment of the present invention, the slot format or slot configuration information transmitted in each of the specific-terminal PDCCHs described above is an uplink transmission or a downlink transmission And the default slot configuration. More specifically, a user scheduled in the downlink notifies only the slot configuration when monitoring a section in which the downlink transmission should not be monitored in the default slot configuration, and a section in which the user scheduled in the uplink should not perform the uplink transmission in the default slot configuration Only the slot configuration is informed. For example, when the default slot configuration uses the slot configuration 4, only the information on the slot configurations 5, 6, and 7 is transmitted to the downlink user as slot format or slot configuration information, Lt; RTI ID = 0.0 > 2 < / RTI > In this scheme, the required slot format or slot configuration information size may vary according to the default slot configuration. In this scheme, the required slot format or slot configuration information size may vary depending on the uplink and downlink.

RNTI  How to use

In another embodiment of the present invention, a specific-terminal PDCCH may be scrambled with different RNTIs to inform the user terminal of the slot configuration. One or more RNTIs may be allocated to one user terminal to inform the slot configuration or a plurality of RNTIs may be generated using one allocated RNTI. For example, several RNTIs may be generated using interleavers of a predetermined pattern from one RNTI. It is also possible to generate several RNTIs using scrambles of a pattern determined from one RNTI. The patterns for generating the RNTI in the user terminal may be promised between the base station and the user terminal in advance. It is possible to inform the slot format and the slot configuration by detecting the specific-terminal PDCCH scrambled with an RNTI among different RNTIs.

The RNTI used as an embodiment of the present invention may be determined according to the slot configuration. Referring to FIG. 14 and FIG. 16, the BS scrambles and transmits a specific-UE PDCCH by selecting one of eight RNTIs according to the current slot configuration. In one embodiment, the RNTI used for the specific-terminal PDCCH scheduling the downlink may be determined according to the location where the downlink OFDM symbol ends. In one embodiment, the RNTI used for the PDCCH scheduling the uplink may be determined according to the position at which the uplink OFDM symbol starts. The RNTI used in one embodiment may be determined according to the default slot configuration. When the base station and the terminal know the default slot configuration, referring to FIG. 14 and FIG. 16, the RNTI can be determined according to the relative difference of the default slot configuration in the current slot configuration of the base station. For example, when it is the default slot configuration using the slot configuration i, and four RNTI, the first RNTI is the default slot configuration with a slot configuration i, the second RNTI is a slot configuration i + j _1, the third RNTI is a slot configuration i a j + _2, fourth RNTI may be used to inform the slot configuration i + j _3. In the above description, j ₁ , j ₂ , and j ₃ may be predetermined to indicate different slot configurations. That is, it informs four different slot format information, one of which can be set to be the same as the default slot format (bit 00). When the base station and the terminal know the default slot configuration, the RNTI used in the embodiment may be determined according to the operation of the user terminal informing the specific-terminal PDCCH and the default slot configuration. For example, when two RNTIs can be used, if a first RNTI is used, the UE performs a scheduled operation on a specific-terminal PDCCH assuming a default slot configuration, and performs a scheduled operation on a specific-terminal PDCCH using a second RNTI I can not. As another example, it is possible to consider a method of specifying an increase or a decrease in the number of symbols of DL or UL, as opposed to informing slot format and slot configuration information. For example, if the default slot format is DL (a) / GP (1) / UP (6-a) ), The base station can have four options as a 1 increase / 2 increase / 1 decrease / a, and by transmitting these options in 2 bits, the DL / UL can be flexibly changed without changing the predetermined slot format and configuration information. A method of changing the number may be considered.

19 is a block diagram of a receiver when informing a slot configuration using an RNTI. The receiver estimating and compensating for the channel using the DM-RS pattern; A QPSK demodulation step; Decoding a channel; Checking the CRC with all possible RNTIs; And determining the PDCCH decoding success based on the CRC check. The receiver checks the CRC using all RNTIs available to inform the slot configuration. At this time, if only one CRC is valid and all the remaining CRCs are invalid, the slot format or slot configuration information and the corresponding operation can be found from the RNTI that provided a valid CRC.

Slot format and slot configuration information Override

In the proposal of the present invention, the slot format and configuration information may be transmitted on the group common PDCCH or common PDCCH, on the specific-terminal PDCCH, or both. In one embodiment of the present invention, if the slot format and configuration information transmitted on the group common PDCCH or the common PDCCH and the slot format and configuration information transmitted on the specific-terminal PDCCH do not match, the user terminal gives priority to the specific-terminal PDCCH , The slot format and the configuration information transmitted from the group common PDCCH or the common PDCCH that has succeeded in reception can be discarded.

The energy consumed when users monitor the DL control channel is proportional to the bandwidth being monitored. In order to reduce the energy consumption, there may be a DL control channel and a user receiving data by reducing the monitoring bandwidth. In addition, there may be a user who can use the data channel by reducing the monitoring bandwidth to receive the DL control channel and changing the bandwidth and center frequency in the DL control information. Users with different DL control information reception bandwidth and data channel reception time will need time to settling the RF circuit. Therefore, the user may have OFDM symbols that can not be used between receiving the DL control information and receiving the data channel. In this case, when OFDM symbols that can not be used by the UEs performing data bandwidth adaptation are generated, the other UEs use the group common PDCCH and / or UE specific PDCCH DL control information allocated to the other UEs, May be considered. Referring to FIG. 20, when a bandwidth change signal is informed on a PDCCH of a first symbol, a system having a 15-kHz subcarrier spacing can not use 2 symbols when a 100-ms time is required for bandwidth change. Systems with spacing can not use 3 symbols.

In order to solve the above problem, the slot format and configuration information informed by the specific-terminal PDCCH described in the present invention can be used. Specifically, the slot configuration in the specific-terminal PDCCH 3 of the user terminal that adjusts the bandwidth can inform the slot format and the configuration information using the fifth OFDM symbol as the DL. UEs that want to schedule the second through fourth OFDM symbols without adjusting the bandwidth can inform the slot format and the configuration information using the OFDM symbol as DL in the second to fourth times in the specific-terminal PDCCH2. The UEs that want to schedule the second through fifth OFDM symbols without adjusting the bandwidth can inform the slot format and the configuration information using the second through fifth ODFM symbols in the specific-terminal PDCCH1 as the DL.

Referring to FIG. 21 as one embodiment, the slot format and the configuration information transmitted on the specific-terminal PDCCH may indicate a start symbol position of a DL data transmission and an end symbol position of a DL data transmission. Since the slot formats and the configuration information transmitted from the group common PDCCH or the common PDCCH are different from the slot format and the configuration information transmitted from the specific-terminal PDCCH, the user terminals can operate with the slot format and the configuration information transmitted from the specific- have.

As another embodiment, it is possible to inform the slot format and the configuration information transmitted on the PDCCH for the specific-terminal to indicate the start symbol position of the DL data transmission and the end symbol position of the DL data transmission or only the slot format and configuration information, May be generated by applying bandwidth adaptation to a specific UE by receiving the scheduling information in the corresponding DCI in the case of receiving the PDCCH for the specific UE regardless of whether the slot format and the configuration information are transmitted in the group common PDCCH or the common PDCCH The MS can receive the data transmission scheduled by the BS in the remaining OFDM symbol.

In another embodiment for solving the above-mentioned problem, when the specific-terminal PDCCH transmits 1-bit slot format and configuration information, the user terminal can be scheduled using 1-bit information. Referring to FIG. 22 and Table 3, a slot format and configuration information for allocating a DL to a symbol may be informed until a bandwidth change user terminal is allocated a DL in a group common PDCCH of a slot or a common PDCCH. The user changing the bandwidth of the user terminal may operate in a default slot configuration, ignoring the 1-bit slot format and the new slot configuration transmitted on the group common PDCCH or the common PDCCH if the configuration information is 1. That is, it can be transmitted through the fifth symbol. If the 1 bit slot format and the configuration information of the user who does not change the bandwidth of the user terminal are 1, the uplink transmission and the downlink reception can be performed in the default slot configuration only when the group common PDCCH or the common PDCCH fails to receive. If the 1-bit slot format and the configuration information of the user who does not change the bandwidth of the user terminal are 0, the uplink transmission and the downlink reception are not performed if the group common PDCCH or the common PDCCH fails to receive. If the 1-bit slot format and the configuration information of the user changing the bandwidth of the user terminal are 0, the bandwidth can be changed and the terminal can operate in the default slot configuration. For reference, the 1-bit BW adaptation in Table 3 indicates whether to perform the bandwidth change and can be transmitted in the DCI or implicitly by the user terminal. For reference, the 1-bit slot format indicator in Table 3 represents 1-bit slot format and configuration information informed by the specific-terminal PDCCH, and this information may be added to the DCI in an explicit manner, or may be transmitted implicitly using the RNTI . In the present embodiment, the 1-bit slot format and the configuration information are transmitted to the PDCCH for a specific terminal. However, in another embodiment, the slot format and the configuration information may be entirely or partially configured in the specific-terminal PDCCH The bit size may vary depending on the configuration to be transmitted, or even when notifying the start-start symbol position of the DL data transmission and the end symbol position of the DL data transmission not the slot format and the configuration information in the specific-terminal PDCCH The bit size may vary.

[Table 3]

While the methods and systems of the present invention have been described in connection with specific embodiments, some or all of those elements or operations may be implemented using a computer system having a general purpose hardware architecture.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

Claims (1)

Method and apparatus for transmitting and receiving data between a terminal and a base station

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