KR20100080316A - Communication apparatus and method using a frame structure - Google Patents

Abstract

PURPOSE: A data transceiving method and a device thereof are provided to prevent the rise of complexity. CONSTITUTION: A transceiver(1001) transmits and receives data through a down link and an uplink. A controller(1003) sets a data frame and controls the transceiver through a preset data frame. The data frame comprises a sub-frame in which data symbols of n number are included.

Description

Method and apparatus for transmitting / receiving data using data frame {COMMUNICATION APPARATUS AND METHOD USING A FRAME STRUCTURE}

The present invention relates to a common frame structure applicable to various bandwidths, and a method and apparatus for transmitting and receiving data using the same.

Due to the development of communication technology, the services provided by the mobile communication system have been gradually developed in various ways such as not only voice communication service but also packet data transmission / reception service and multimedia broadcasting service for transmitting a large amount of data.

Third generation communication services such as WCDMA, which are currently in service, can transmit and receive not only voice but also large amounts of data at high data rates. Furthermore, in consideration of the rapid increase in data traffic in the future, an evolving network having a wider bandwidth can be used. In order to make this, standardization works such as Long-Term Evolution Network (LTE) and IEEE802.16m are actively in progress.

In particular, IEEE 802.16m, which is actively working on standardization, aims to develop a standard that satisfies IMT-Advanced system requirements while maintaining interoperability with existing 802.16 standard-based terminal and base station equipment.

The evolved IMT-Advanced communication system is a broadband wireless access communication system, which has a wide service area and can support a high transmission speed. The broadband wireless access communication system as described above includes Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Frequency Division in order to support a broadband transmission network in a physical channel. A multiplexing access (hereinafter referred to as 'OFDMA') scheme is used, and the OFDM / OFDMA scheme enables high-speed data communication by transmitting and receiving physical channel signals using a plurality of subcarriers.

FIG. 1 is a diagram schematically illustrating uplink (UL) and downlink (DL) frame structures of a broadband wireless access communication system using an OFDM / OFDMA scheme.

Referring to FIG. 1, the uplink and downlink frame structures include a preamble (101) region, a frame control header (FCH) region, a DL / UL MAP 103, 104 control signal region, and a plurality of data. It consists of a burst area.

A preamble sequence, which is a synchronization signal for obtaining mutual synchronization between the base station and the UE, is transmitted through the preamble 101 region, and channel allocation information related to the DL-MAP 103 is transmitted through the FCH 102 region. Channel code information is provided, and channel allocation information of data bursts in downlink and uplink is provided through the DL / UL-MAP 103 and 104 region. In addition, a guard time (guard time) is inserted between the downlink frame and the uplink frame, and the TTG (transmit / receive transition gap) is a guard interval between the downlink burst and the continuous uplink burst, A receive / transmit transition gap (RTG) corresponds to a guard interval between an uplink burst and a continuous downlink burst.

On the other hand, the IMT-Advanced system requires the system to support various bandwidths.In particular, IEEE802.16m, which is currently being standardized, uses 5 MHz, 7 MHz, 8.75 MHz, 10 MHz and 20 MHz as the bandwidth of the system channel. It is defined. However, in the current IMT-Advanced system, a specific frame structure is not defined, and in particular, in the case of IEEE802.16m, if the frame is individually designed for each bandwidth, the complexity of the system increases. Furthermore, even when the lengths of the CPs of the frame are variously configured, the frame structure is different. However, when a frame structure having a different CP length is simultaneously used in one communication system, interference between adjacent cells occurs. Occurs.

The present invention is to solve the above problems, to provide a frame structure that can be commonly applied to various bandwidths required by the system and a method and apparatus for transmitting and receiving data through the frame structure.

A data transmission and reception method according to an embodiment of the present invention for achieving the above object, in the data transmission method in an Orthogonal Frequency Division Multiplexing Access (OFDMA) communication system of a time division duplex (TDD) method, Setting a data frame including a sub-frame of the data frame; and transmitting and receiving data through the set data frame, wherein the cyclic prefix CP of the data frame is a valid OFDM symbol. 1/16 of the length, the bandwidth of the transmission channel is 7MHz, characterized in that the data frame is configured such that the maximum number of sub-frame consisting of six data symbol units.

Preferably, the ratio of the number of downlink and uplink subframes of the data frame is K: J, the number of data symbols allocated to the downlink is 6 * K-1, and the data symbols assigned to the uplink The number is 6 * J, and one data symbol is allocated to a transmit / receive transition gap (TGT), and the last subframe of the downlink is configured by 5 symbol units.

Also preferably, the ratio of the number of the downlink and uplink subframes of the data frame is 5: 1, and the first subframe to the fourth subframe and the uplink subframe of the downlink are all The subframe is composed of 6 symbol units, and the fifth subframe of the downlink is configured of a subframe of 5 symbol units.

In the data transmission and reception method according to an embodiment of the present invention for achieving the above object, in the data transmission method in an Orthogonal Frequency Division Multiplexing Access (OFDMA) communication system of the frequency division duplex (FDD) method, Setting a data frame including a plurality of subframes, and transmitting and receiving data through the set data frame, wherein the cyclic prefix CP of the data frame is 1 / time of an effective OFDM symbol length. 16, the bandwidth of the transmission channel is 7MHz, and the data frame is characterized by consisting of only six sub-frame (sub-frame) of six data symbols.

Data transmission and reception apparatus according to an embodiment of the present invention for achieving the above object, a transceiver for transmitting and receiving data through the downlink and uplink, and at least one sub-frame consisting of n data symbols (sub-frame) And a controller configured to control the transceiver to transmit and receive data through the set data frame, wherein the controller is configured to maximize the number of sub-frames. The data frame is configured.

Preferably, in the apparatus, the cyclic prefix CP of the data frame is 1/16 of an effective OFDM symbol length, a bandwidth of a transmission channel is 7 MHz, and the data symbol unit n of the subframe is 6 do.

According to the present invention, by proposing a frame structure that can be commonly applied in a system that requires support of various bandwidths, there is an effect that can prevent the problem of increasing the complexity of the system.

In addition, according to the present invention, it is possible to prevent interference between DL and UL of frames having different CP lengths in a TDD data frame, and an FDD frame having commonality with the TDD frame structure is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or similar components will be given the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. In addition, in describing the present invention, when it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, it should be noted that the accompanying drawings are only for easily understanding the spirit of the present invention and should not be construed as limiting the spirit of the present invention by the accompanying drawings.

Hereinafter, the term terminal is used, but the terminal may be referred to as a subscriber station (SS), a user equipment (UE), a mobile equipment (ME), or a mobile station (MS). The terminal may be a portable device having a communication function, such as a mobile phone, a PDA, a smart phone, a notebook computer, or a non-portable device such as a PC or a vehicle-mounted device.

2 is a diagram schematically showing an OFDM / OFDMA symbol structure used in the present invention.

In OFDM / OFDMA, the guard interval is not used in a certain part in front of each symbol in consideration of the influence of inter symbol interference (ISI) caused by the reflected wave.As shown, a part of the rear part of the symbol is guard interval interval. Copy it and insert it. As described above, the front part of the symbol inserted in the Guard Interval is called a cyclic prefix (CP).

If the total length of one OFDM symbol is Ts and the length of CP is Tg, the effective OFDM symbol length is Tb except the length Tg of CP from the total OFDM symbol length Ts.

The frame structure including the OFDM / OFDMA symbols may be determined according to the frame parameters shown in Table 1 below, and the frame size and the number of subframes and symbols.

Nominal Channel Bandwidth (MHz) 5 7 8.75 10 20 Over-sampling factor 28/25 8/7 8/7 28/25 28/25 Sampling Frequency (MHz) 5.6 8 10 11.2 22.4 FFT size 512 1024 1024 1024 2048 Sub-Carrier Spacing (KHz) 10.937500 7.812500 9.765625 10.937500 10.937500 Useful symbol Time Ts (μs) 91.429 128 102.4 91.429 91.429 Cyclic Prefix (CP)
T _g = 1/8 T _u Symbol Time T _s (μs) 102.857 144 115.2 102.857 102.857 FDD Number of OFDM symbols per Frame 48 34 43 48 48 Idle time (μs) 62.857 104 46.40 62.857 62.857 TDD Number of OFDM symbols per Frame 47 33 42 47 47 TTG + RTG (μs) 165.714 248 161.6 165.714 165.714 Cyclic Prefix (CP)
T _g = 1/16 T _u Symbol Time T _s (μs) 97.143 136 108.8 97.143 97.143 FDD Number of OFDM symbols per Frame 51 36 45 51 51 Idle time (μs) 45.71 104 104 45.71 45.71 TDD Number of OFDM symbols per Frame 50 35 44 50 50 TTG + RTG (μs) 142.853 240 212.8 142.853 142.853 Cyclic Prefix (CP)
T _g = 1/4 T _u Symbol Time T _s (μs) 114.286 160 128 114.286 114.286 FDD Number of OFDM symbols per Frame 43 31 39 43 43 Idle time (μs) 85.694 40 8 85.694 85.694 TDD Number of OFDM symbols per Frame 42 30 38 42 42 TTG + RTG (μs) 199.98 200 136 199.98 199.98

Referring to Table 1, when the transmission channel band and the CP length of the system are determined, the number of OFDM symbols and other necessary parameters for frame design can be determined.

Hereinafter, the frame structure will be described in detail with reference to the accompanying drawings.

3 is a diagram schematically illustrating a high level frame structure according to an embodiment of the present invention.

As shown in the figure, the frame structure applied to the system of the present invention has a frame of 5 ms units as a basic component, and the frame may be defined as an interval between preambles as one basic transmission unit.

The frame may include a plurality of transmission time intervals (TTIs) having different sizes. The TTI is a basic unit of scheduling performed in a medium access control (MAC) layer, and the TTI is called a radio resource allocation unit. can do.

The frame includes at least one subframe, and the size of the subframe is determined in symbol units. In the present invention, subframes are defined as four types of Type-1, Type-2, Type-3, and Type-4 according to the bandwidth and CP length of the system. The Type-1 subframe consists of six OFDM symbols, the Type-2 subframe consists of seven OFDM symbols, the Type-3 subframe consists of five OFDM symbols, and the Type-4 subframe consists of nine It consists of an OFDM symbol.

As shown, a super frame including a plurality of the frames is configured, and the super frame may be configured, for example, in units of 20 ms. When the super frame is configured, system configuration information and broadcast information for initial fast cell selection and low latency service are set as a transmission unit, and generally two to six frames are set as one transmission unit. It consists of super frames. In addition, each 5ms frame consists of a plurality of sub-frames, and each subframe consists of a plurality of OFDM / OFDMA symbols. Each super frame includes one super frame header (SFH) including a broadcast channel, and the SFH is located in the first downlink (DL) subframe of the corresponding super frame.

The frame structure may be designed according to a bandwidth, a duplex scheme, a CP length, and the like of a system channel.

4 is a diagram schematically illustrating a frame structure of an FDD scheme according to an embodiment of the present invention.

In the FDD mode, downlink and uplink transmissions are distinguished in the frequency domain, and all subframes in each frame are capable of both downlink and uplink transmissions. A UE in FDD mode may receive a data burst in any downlink subframe while simultaneously accessing an uplink subframe.

4 defines a frame structure in the FDD mode when the channel bandwidths are 5, 10 and 20 MHz and the CP length is 1/8 Tb. A 20 ms superframe includes four 5 ms frames (F0, F1, F2, F3). One frame F2 includes eight subframes SF0, SF1, SF2, SF3, SF4, SF5, SF6, SF7 having a length of 0.617 ms and an idle time interval of 62.86 μs. In addition, the subframe includes a Type-2 subframe including seven OFDM symbols S0, S1, S2, S3, S4, S5, and S6.

5 is a diagram schematically illustrating a frame structure of a TDD scheme according to an embodiment of the present invention.

In the TDD mode, downlink and uplink transmissions are distinguished in the time domain, and after downlink transmission time intervals, uplink transmission time intervals are allocated to transmit and receive data through downlink and uplink.

FIG. 5 defines a TDD mode frame structure in the case of channel bandwidths of 5, 10, and 20 MHz and CP length of 1/8 Tb, as in FIG. 4, and a 20 ms superframe includes four 5 ms frames (F0, F1, F2, One frame F2 includes eight subframes (SF0, SF1, SF2, SF3, SF4, SF5, SF6, SF7) having a length of 0.617 ms and an idle time interval of 62.86 μs. The frame F2 is composed of consecutive D downlink frames and consecutive U uplink frames determined according to a ratio (D: U) of DL and UL, and a ratio of DL and UL is 5: 3. In this case, five subframes SF0, SF1, SF2, SF3, SF4 are configured as downlink frames, and three subframes SF5, SF6, SF7 are configured as uplink frames. One idle symbol for distinguishing the DL and the UL is inserted between the last downlink subframe SF4 and the first uplink subframe SF5 to inform that the switch is switched from the DL to the UL. As such, the gap inserted between the downlink and the uplink is called a TTG (transmit transition gap), and the gap inserted between the uplink and the downlink is called a receive transition gap (RTG). And uplink transmission can be distinguished.

As shown in FIG. 5, the last downlink subframe SF4 is composed of five OFDM symbols and one last Idle symbol S5, and the Idle symbol S5 is a TTG (transmit / receive transition gap).

6 illustrates a TDD and FDD frame structure according to another embodiment of the present invention.

In the frame structure shown in FIG. 6, the CP length is 1 / 16Tb, and the transmission channel bandwidths are assumed to be 5, 10, and 20 MHz. In the case of a TDD frame, the ratio of DL and UL is 5: 3 and the length of the TDD / FDD frame is basically 5ms. The total number of OFDM symbols in one frame (TDD frame, FDD frame) is 48, and one frame is composed of a total of eight subframes. Accordingly, unlike the embodiments of FIGS. 4 and 5 described above, the subframes cannot be configured in the same type, and the Type-1 subframe 610 having 6 OFDM symbols and the Type- having 7 OFDM symbols Two subframes 620 are configured in two forms.

The Type-1 subframe 610 consists of six OFDM symbols and has a length of 0.583 ms, and the Type-2 subframe 620 consists of seven OFDM symbols and has a length of 0.680 ms. The TDD Frame and the FDD Frame have the same size and subprime configuration, but in the case of the TDD Frame, since the TTG is required between the DL and the UL, the last symbol of the fifth subframe SF4 is composed of the Idle symbol 611. .

As described above, when the channel bandwidth is 5, 10, and 20 MHz, the frame structure is designed such that a Type-1 subframe composed of 6 symbol units is configured as the basic subframe, and the basic subframe (Type-1 subframe) The frame is configured to be the maximum number in this one frame. In this way, the frame is configured to have the maximum number of basic subframes. Since the minimum size of the TTI, which is a basic unit when transmitting and receiving data using the frame between the transmitting and receiving terminals, is a subframe, a pilot and a resource block (PHY) of the physical layer (PHY) resource block) has the advantage of bringing the same configuration and design as possible.

Hereinafter, when the channel bandwidth is 7MHz and the CP length is 1 / 8Tb and when the CP length is 1 / 16Tb, the TDD frame structure will be described with reference to related drawings.

7 illustrates a TDD frame structure according to an embodiment of the present invention.

Referring to Table 1, when the frame transmission channel bandwidth is 7 MHz, the number of OFDM symbols available for 1 / 8Tb CP length is 34, and the number of OFDM symbols available for 1 / 16Tb CP length is 36.

In the basic frame structure in the 5, 10, and 20 MHz channel transmission bands described above, the Type-1 subframe size composed of 6 symbol units is used as the basic subframe. We propose a structure that uses a Type-1 subframe composed of symbol units as a basic subframe to the maximum.

First, a TDD frame 710 having a CP length of 1 / 8Tb has a DL / UL ratio of 4: 2. In the TDD mode, the first subframe is composed of six symbols in consideration of the fact that the first subframe is used for SFH. Composed of one subframe (SF0), the second and third subframes (SF1, SF2) is composed of a Type-3 subframe consisting of five symbols, the fourth DL subframe (SF3) is a Type-1 subframe By taking the structure of, but assigning the last one symbol as a TTG symbol between DL and UL, the fourth subframe is eventually converted to a Type-3 subframe of 5 symbol units. The UL subframes SF4 and SF5 are all composed of Type-1 subframes having 6 symbol units. Through the above structure, the frame can be basically configured so that the basic subframe composed of six symbol units is maximum, thus forming a frame having commonality with the frame structure in the other channel transmission band even in the 7 MHz channel transmission band. It can transmit and receive data through this.

As described above, in the TDD frame 720 having a CP length of 1 / 16Tb, the basic subframe is composed of 6 symbol units of Type-1, and the frame is configured such that the basic subframe is maximum. Accordingly, as shown, except for the last subframe SF3 of the DL, all are configured as Type-1 subframes of 6 symbols. Since the last subframe SF3 of the DL allocates one symbol for TTG, it consists of Type-3 subframes of five symbols.

In addition, as described above, mutual interference occurs in consideration of an environment in which a TDD frame 710 structure having a CP length of 1/8 Tb and a frame 720 structure having a CP length of 1/16 Tb coexist. To avoid this, the TDD frame structure should be designed so that DL and UL boundaries between TDD frames 710 and 720 having different CP lengths do not overlap each other.

In the case of a TDD frame 720 having a CP length of 1/16 Tb, in order to prevent interference from occurring at the DL / UL boundary point of the 1/8 Tb TDD frame, 6 * k-1 OFDM symbols are used on the DL side. 6 * j OFDM symbols are also allocated to the side. In the example shown, k = 4 and j = 2. In addition, referring to the comparison of the two frames of FIG. 7, it can be seen that the boundary points of the DL and the UL do not overlap.

Comparing the two frames 710 and 720 based on the number of symbols allocated, the number of symbols in the TDD frame 710 of 1/8 Tb is 34 (21 DLs, 1 TTG, and 12 ULs). The number of symbols in the frame 720 of 1 / 16Tb is 36 (DL: 6 * k-1 = 23, TTG: 1, UL: 6 * j = 12). Therefore, when designing the TDD frame 720 at 1/16 Tb based on the TDD frame 710 of 1/8 Tb, two OFDM symbols remaining compared to the number of symbols of the 1/8 Tb TDD frame 710 are determined. If two subframes SF1 and SF2 of 5 symbols are allocated, one data frame 720 includes 6 Type-1 subframes of 6 symbols. As described above, the last symbol of the DL is allocated for TTG.

8 is a diagram illustrating a TDD frame structure according to another embodiment of the present invention, and corresponds to an embodiment in which a DL / UL ratio is 5: 1.

Looking at the TDD frame 810 having a CP length of 1 / 8Tb, since the total number of symbols is 34, four Type-1 subframes consisting of six symbol units and four Type-3 subframes consisting of five symbol units are described. When two subframes are configured, the basic subframe composed of six symbol units can be configured to be the maximum, and thus, the frame can be designed to have commonality with the frame structure in other channel transmission bands even in the 7 MHz channel transmission bands. . In the TDD mode, the first subframe is preferably configured as a Type-1 subframe SF0 consisting of 6 symbols in consideration of being used for the SFH (Super Frame Header). In addition, since the last one symbol of the DL is allocated as a TTG symbol between the DL and the UL, the last subframe of the DL is configured as a Type-1 subframe composed of six symbol units, and the last one symbol is referred to as a TTG. When assigned, the Type-1 subframe is converted into a Type-3 subframe SF4 composed of 5 symbol units.

As described above with reference to FIG. 7, the TDD frame 820 having a CP length of 1 / 16Tb is a Type-1 subframe in which the basic subframe is composed of 6 symbol units, and the basic subframe is maximum. Configure the frame so that Accordingly, as shown, except for the last subframe SF4 of the DL, all are configured as a basic subframe of 6 symbols. Since the last subframe SF4 of the DL allocates one symbol for TTG, it consists of Type-3 subframes of five symbols.

In addition, as described above, mutual interference occurs in consideration of an environment in which a TDD frame 810 structure having a CP length of 1/8 Tb and a frame 820 structure having a CP length of 1/16 Tb coexist. To avoid this, the TDD frame structure must be designed so that DL and UL boundaries between the TDD frames 810 and 820 do not overlap each other.

As shown, in the case of a TDD frame 820 having a CP length of 1/16 Tb, in order to prevent interference from occurring at the DL / UL boundary point of the 1/8 Tb TDD frame, 6 * k-1 The OFDM symbol is also allocated 6 * j OFDM symbols on the UL side. In the example shown, k = 5 and j = 1.

9 illustrates an FDD frame structure according to an embodiment of the present invention.

In this embodiment, the FDD frame is designed to have commonality with the TDD structure.

That is, since TTG is not required in the FDD, all sixty symbols can be used to configure six Type-1 subframes consisting of six symbols. Therefore, since 6 sub-frames are used to the maximum, the PHY structure and the MAC structure defined in the existing 5, 10, and 20 MHz bands can be recycled, and the system complexity can be reduced.

10 is a block diagram showing a data transmission and reception apparatus according to an embodiment of the present invention.

The apparatus includes a transceiver 1001 for transmitting and receiving data through downlink and uplink, and a controller 1003.

The controller 1003 sets a data frame including at least one subframe composed of n data symbols, and controls the transceiver 1001 to transmit and receive data through the set data frame. do.

In addition, the controller 1003 configures a maximum number of subframes composed of n symbol units in configuring a data frame.

Preferably, the data frame is configured such that a basic sub-frame consisting of six data symbols is maximum, and a specific frame is formed by referring to the bandwidth of the transmission channel and the system parameters of Table 1 above.

The method according to the invention described thus far can be implemented in software, hardware, or a combination thereof. For example, the method according to the present invention may be stored in a storage medium (eg, terminal internal memory, flash memory, hard disk, etc.) and executed by a processor (eg, terminal internal microprocessor). It may be implemented as codes or instructions within a software program that can be.

In the above described exemplary embodiments of the present invention by way of example, but the scope of the present invention is not limited only to these specific embodiments, the present invention is in various forms within the scope of the spirit and claims of the present invention Can be modified, changed, or improved.

1 is a view schematically showing an uplink and downlink frame structure of a broadband wireless access communication system

2 is a diagram schematically showing an OFDM / OFDMA symbol structure used in the present invention.

3 is a schematic illustration of a high level frame structure in accordance with the present invention;

4 schematically illustrates a frame structure of an FDD scheme according to an embodiment of the present invention.

5 schematically illustrates a frame structure of a TDD scheme according to an embodiment of the present invention.

6 illustrates a TDD and FDD frame structure according to another embodiment of the present invention.

7 illustrates a TDD frame structure according to another embodiment of the present invention.

8 illustrates a TDD frame structure according to another embodiment of the present invention.

9 illustrates an FDD frame structure according to another embodiment of the present invention.

10 is a block diagram showing an apparatus for transmitting and receiving data according to an embodiment of the present invention.

Claims (7)

A data transmission method in an Orthogonal Frequency Division Multiplexing Access (OFDMA) communication system using a time division duplex (TDD) method, Setting a data frame including a plurality of sub-frames, and And transmitting and receiving data through the set data frame, The cyclic prefix CP of the data frame is 1/16 of an effective OFDM symbol length, and a bandwidth of a transmission channel is 7 MHz. The data frame is a data transmission and reception method, characterized in that configured to the maximum number of sub-frame consisting of six data symbol units. 3. The method of claim 2, The ratio of the number of downlink and uplink subframes of the data frame is K: J, The number of data symbols allocated to the downlink is 6 * K-1, The number of data symbols allocated to the uplink is 6 * J, The one data symbol is allocated in a transmit / receive transition gap (TGT), and the last subframe of the downlink is configured in units of five symbols. 3. The method of claim 2, The ratio of the number of the downlink and uplink subframes of the data frame is 5: 1, The first subframe to the fourth subframe of the downlink and the subframe of the uplink are all composed of subframes of 6 symbol units, and the fifth subframe of the downlink is a subframe of 5 symbol units Data transmission and reception method, characterized in that consisting of. A data transmission method in an Orthogonal Frequency Division Multiplexing Access (OFDMA) communication system using a frequency division duplex (FDD) method, Establishing a data frame including a plurality of subframes, and And transmitting and receiving data through the set data frame, The cyclic prefix CP of the data frame is 1/16 of an effective OFDM symbol length, and a bandwidth of a transmission channel is 7 MHz. The data frame is a data transmission and reception method, characterized in that consisting of only six sub-frames (sub-frame) consisting of six data symbol units. In the data transmission and reception apparatus, A transceiver for transmitting and receiving data through downlink and uplink, and A controller configured to set a data frame including at least one sub-frame consisting of n data symbols, and control the transceiver to transmit and receive data through the set data frame, And the controller configures the data frame such that the number of sub-frames is maximum. The method of claim 5, wherein the data frame, The cyclic prefix (CP) is 1/16 of the effective OFDM symbol length, The transmission channel has a bandwidth of 7 MHz. And a data symbol unit n of the subframe is six. The method of claim 5, The apparatus for transmitting and receiving data supports Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiplexing Access (OFDMA), and the downlink and uplink are time division duplex (TDD) or mutually divided by time. Device for transmitting and receiving data, characterized in that it is Frequency Division Duplex (FDD).

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