KR101539802B1 - Method of communication using frame - Google Patents

Abstract

A method and apparatus are provided for a terminal to communicate with a base station. A method according to an embodiment includes exchanging frames of data with a base station. Wherein the frame of data comprises: a) a plurality of first subframes each comprising a first number of orthogonal frequency division multiple access (OFDMA) symbols, and b) a second number of OFDMA symbols And a plurality of second sub-frames including the second sub-frame.

Description

[0001] METHOD OF COMMUNICATION USING FRAME [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless communication, and more particularly, to a communication method using a frame in a wireless communication system.

The Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard provides techniques and protocols for supporting broadband wireless access. Standardization progressed from 1999 and IEEE 802.16-2001 was approved in 2001. This is based on a single carrier physical layer called 'WirelessMAN-SC'. In the IEEE 802.16a standard approved in 2003, 'WirelessMAN-OFDM' and 'WirelessMAN-OFDMA' were added in addition to 'WirelessMAN-SC' in the physical layer. The IEEE 802.16-2004 standard was revised in 2004 after the IEEE 802.16a standard was completed. IEEE 802.16-2004 / Cor1 (hereinafter referred to as IEEE 802.16e) was completed in 2005 in the form of 'corrigendum' to correct bugs and errors in the IEEE 802.16-2004 standard.

Currently, standardization of IEEE 802.16m, which is a new technical standard based on IEEE 802.16e, is underway. IEEE 802.16m, which is a newly developed technical standard, should be designed to support IEEE 802.16e. That is, it should be constructed so as to efficiently cover the existing technology of the newly designed system (IEEE 802.16m) (IEEE 802.16e). This is called Backward Compatibility. The following are some of the considerations in designing IEEE 802.16m.

First, the terminal of the new technology should operate with the same performance as the base station and the terminal of the existing technology. Hereinafter, a system (terminal or base station) adopting a new technology will be referred to as a new system, and a system employing existing technologies will be referred to as a legacy system. Second, the new system and the legacy system must operate on the same radio frequency (RF) carrier and the same bandwidth. Third, the new BS must support the case where the new MS and the legacy MS coexist on the same RF carrier, and the performance of the whole system should be improved by the ratio of the new MS. Fourth, the new base station should support the handover of the legacy terminal and the handover of the new terminal according to the handover performance between the legacy base stations. Fifth, the new base station must support the new terminal and support the legacy terminal, and the legacy base station should be able to support it at the level provided to the legacy terminal.

The new base station schedules radio resources for a legacy terminal or a new terminal within a bandwidth that can be supported by the new base station. The scheduling of the radio resources may be performed in a logical frame consisting of a plurality of OFDM symbols in a time domain and a plurality of subchannels in a frequency domain. Accordingly, studies on a frame structure capable of satisfying the backwardness of the IEEE 802.16e system in the IEEE 802.16m system are underway.

In particular, when a frame structure according to a time division duplexing (TDD) scheme having a different CP (Cyclic Prefix) length coexists in an adjacent cell, there is a possibility that boundary points of the downlink and the uplink overlap each other and interference occurs. Therefore, it is necessary to design a TDD frame structure so that interference does not occur between TDD frame structures coexisting in adjacent cells.

In addition, the system profile based on the conventional IEEE 802.16 standard supports only a TDD (Time Division Duplexing) scheme, but also supports an FDD (Frequency Division Duplexing) scheme in which uplink and downlink transmissions are simultaneously performed in different frequency bands There is an attempt. Therefore, it is necessary to design an FDD frame structure having a commonality with the TDD frame structure for convenience of system design and hardware sharing.

SUMMARY OF THE INVENTION The present invention provides a TDD frame having CPs of various lengths for mitigating interference between an uplink and a downlink transmission.

According to another aspect of the present invention, there is provided a method of transmitting an FDD frame having commonality with the TDD frame.

In one aspect of the invention, a method is provided for a terminal to communicate with a base station. The method includes exchanging frames of data with a base station, the frames of data comprising: a) a plurality of first subframes each comprising a first number of orthogonal frequency division multiple access (OFDMA) symbols; b) And a plurality of second subframes each of which includes a second number of OFDMA symbols different from the first number.

The step of exchanging a frame of data with the base station may include at least one of transmitting a frame of the data to the base station and receiving a frame of the data to the base station.

The step of exchanging frames of data with the base station may include decomposing the frames into data stored in a data buffer in the terminal.

The number of the first plurality of subframes and the number of the plurality of second subframes may be predetermined or may be determined based on an instruction received from the base station.

The frame may have a cyclic prefix (CP) length of 1/16 Tu (useful symbol time).

The first number of OFDMA symbols may be 7 symbols and the second number of OFDMA symbols may be 6 symbols.

The exchanging may perform time division duplexing (TDD) of the frame with another frame.

The plurality of first sub-frames may include two first sub-frames, and the plurality of second sub-frames may include six second sub-frames.

One of the six second subframes may include an idle symbol.

The frame may include the six second sub-frames following one first sub-frame and another second sub-frame following the six second sub-frames.

And the 4 < th > second subframe among the 6 second subframes may include idle symbols.

The idle symbol may be a sixth symbol of the fourth subframe.

The frame may include a plurality of downlink subframes and a subsequent plurality of uplink subframes.

Wherein the plurality of downlink subframes include at least one of the plurality of first subframes and the plurality of second subframes, and the plurality of uplink subframes include at least one of the plurality of first subframes And at least one of the remaining one and the plurality of second sub-frames.

The ratio of the plurality of downlink subframes to the plurality of uplink subframes may be one of 4: 4, 6: 2, 7: 1, and 5: 3.

The frame may include a transmit / receive transition gap (TTG) between the plurality of downlink subframes and the plurality of uplink subframes.

The exchanging may perform frequency division duplexing (FDD) of the frame with another frame.

The plurality of first sub-frames may include three first sub-frames, and the plurality of second sub-frames may include five second sub-frames.

The frame may include a first first sub-frame, three second sub-frames, a second second sub-frame, two second sub-frames, and a third third sub-frame in that order.

In another aspect of the present invention, a terminal for communicating with a base station is provided. And a processor coupled to the display and the transceiver for exchanging frames of data with a base station, the frame of data comprising: a) a first number of orthogonal frequency division multiple (OFDMA) access symbols, and b) a plurality of second sub-frames, each of the second sub-frames including a second number of OFDMA symbols different from the first number.

1 is a block diagram illustrating a wireless communication system.
Fig. 2 shows an example of a frame structure.
Figure 3 shows an example of a frame hierarchy.
FIG. 4 shows an example of a conventional TDD frame structure with a CP length of 1 / 8Tu when the DL / UL ratio is 4: 4.
FIG. 5 shows an example of a conventional TDD frame structure having a CP length of 1 / 8Tu when the DL / UL ratio is 5: 3.
6 shows an example of a conventional TDD frame structure in which the CP length is 1 / 8Tu when the DL / UL ratio is 6: 2.
7 shows an example of a conventional TDD frame structure in which the CP length is 1 / 8Tu when the DL / UL ratio is 7: 1.
8 shows an example of a conventional FDD frame structure having a CP length of 1 / 8Tu.
9 is a diagram illustrating a TDD frame structure in which the CP length is 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an exemplary embodiment of the present invention when the DL / UL ratio is 4: 4 .
10 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an embodiment of the present invention when the DL / UL ratio is 5: 3 .
11 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an exemplary embodiment of the present invention when the DL / UL ratio is 6: 2 .
12 is a diagram illustrating a TDD frame structure having a CP length of 1/4 Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an exemplary embodiment of the present invention when the DL / UL ratio is 7: 1 .
13 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention.
FIG. 14 is a diagram illustrating a TDD frame having a basic sub-frame composed of SFT-2 subframes having a CP length of 1/4 Tu and an FDD frame having a commonality with the TDD frame according to an embodiment of the present invention.
15 is a diagram illustrating a TDD frame structure having a CP length of 1 / 16Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention.
16 is a diagram illustrating a TDD frame structure having a CP length of 1 / 32Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention.
17 is a block diagram showing a radio communication apparatus.

1 is a block diagram illustrating a wireless communication system. Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, and the like.

Referring to FIG. 1, a wireless communication system includes a user equipment (UE) 10 and a base station (BS) 20. The terminal 10 may be fixed or mobile and may be called by other terms such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a wireless device, The base station 20 generally refers to a fixed station that communicates with the terminal 10 and may be referred to by other terms such as a Node B, a Base Transceiver System (BTS), and an Access Point. One base station 20 may have more than one cell.

Hereinafter, downlink (DL) means communication from the base station 20 to the terminal 10, and uplink (UL) means communication from the terminal 10 to the base station 20. In the downlink, the transmitter may be part of the base station 20, and the receiver may be part of the terminal 10. [ In the uplink, the transmitter may be part of the terminal 10, and the receiver may be part of the base station 20.

The wireless communication system may be an Orthogonal Frequency Division Multiplexing (OFDM) / Orthogonal Frequency Division Multiple Access (OFDMA) based system. OFDM uses multiple orthogonal subcarriers. OFDM uses the orthogonality property between IFFT (Inverse Fast Fourier Transform) and FFT (Fast Fourier Transform). In the transmitter, data is transmitted by performing IFFT. The receiver performs an FFT on the received signal to recover the original data. The transmitter uses an IFFT to combine multiple subcarriers, and the receiver uses a corresponding FFT to separate multiple subcarriers.

Fig. 2 shows an example of a frame structure. A frame is a data sequence for a fixed time that is used by a physical specification. Refer to Section 8.4.4.2 of the IEEE Standard 802.16-2004 "Part 16: Air Interface for Fixed Broadband Wireless Access Systems".

Referring to FIG. 2, a frame includes a downlink (DL) frame and an uplink (UL) frame. Time Division Duplex (TDD) is a scheme in which uplink and downlink transmissions share the same frequency but occur at different times. The DL frame is temporally ahead of the UL frame. The DL frame starts in the order of a preamble, a frame control header (FCH), a downlink (DL) -MAP, an uplink (UL) -MAP, and a burst area. A guard time for distinguishing the UL frame from the DL frame is inserted in the middle part of the frame (between the DL frame and the UL frame) and the last part (after the UL frame). The transmit / receive transition gap (TTG) is the gap between the downlink burst and the subsequent uplink burst. A receive / transmit transition gap (RTG) is a gap between an uplink burst and a subsequent downlink burst.

The preamble is used for initial synchronization, cell search, frequency offset, and channel estimation between the base station and the terminal. The FCH includes the length of the DL-MAP message and the coding scheme information of the DL-MAP.

The DL-MAP is an area to which the DL-MAP message is transmitted. The DL-MAP message defines a downlink channel connection. The DL-MAP message includes a configuration change count of DCD (Downlink Channel Descriptor) and a base station ID. DCD describes a downlink burst profile applied to the current map. The downlink burst profile refers to the characteristics of the downlink physical channel, and DCD is periodically transmitted by the base station through the DCD message.

The UL-MAP is an area in which a UL-MAP message is transmitted. The UL-MAP message defines the uplink channel connection. The UL-MAP message includes a configuration change count of a UCD (Uplink Channel Descriptor), and an effective start time of UL allocation defined by UL-MAP. The UCD describes an Uplink Burst Profile. The uplink burst profile refers to the characteristics of the uplink physical channel, and the UCD is periodically transmitted by the base station through the UCD message.

Figure 3 shows an example of a frame hierarchy.

Referring to FIG. 3, each superframe is divided into four radio frames (hereinafter referred to as frames) having the same size. The superframe may include a superframe header. The superframe header can be assigned to the first frame among the plurality of frames constituting the superframe. A common control channel may be assigned to the superframe header. The common control channel is used to transmit control information that all terminals can commonly use, such as information on frames constituting a super frame or system information. System information is essential information that a terminal needs to know in order to communicate with a base station, and the base station periodically transmits system information. The system information can be periodically transmitted every 20 to 40 ms, and the size of the super frame can be determined by reflecting the transmission period of the system information. In FIG. 3, the size of each super frame is 20 ms, and the size of each frame is 5 ms. However, the present invention is not limited thereto.

One frame is composed of 8 subframes. One subframe may be allocated for uplink or downlink transmission. Each subframe for downlink transmission may include a signal for resource allocation. The subframe may comprise, for example, six OFDM symbols. This is an example only and not a limitation.

Hereinafter, a TDD frame structure and an FDD frame structure satisfying the backwardness to a legacy system will be described. Here, a TDD (Time Division Duplexing) frame refers to a frame that uses the entire frequency band as the uplink or downlink, and distinguishes the uplink and the downlink in the time domain. The FDD (Frequency Division Duplexing) frame means that uplink transmission and downlink transmission occupy different frequency bands and are performed at the same time. A frame satisfying the backwardness to the legacy system is called a dual frame. The dual frame includes a resource area that supports a legacy system and a resource area that supports a new / evolved system. The legacy system means an IEEE 802.16e system, and the new system can mean IEEE 802.16m. The term used in the frame structure of IEEE 802.16e described in FIG. 2 may be defined and used in the same frame structure of the IEEE 802.16m, and may be partially changed.

Table 1 below shows frame parameters.

Transmission Bandwidth (MHz) 5 10 20 Over Sampling Factor 28/25 Sampling Frequency (MHz) 5.6 11.2 22.4 FFT Size 512 1024 2048 Subcarrier Spacing (KHz) 10.94 OFDM Symbol Time, Tu (μs) 91.4 Cyclic Prefix (CP) Ts (μs) OFDM Symbols per Frame Idle Time (μs) no legacy support Tg = 1 / 4Tu 91.4 + 22.85 = 114.25 43 87.25 legacy support Tg = 1 / 8Tu 91.4 + 11.42 = 102.82 48 64.64 no legacy support Tg = 1 / 16Tu 91.4 + 5.71 = 97.11 51 47.39 no legacy support Tg = 1 / 32Tu 91.4 + 2.86 = 94.26 53 4.22

In order to satisfy the backwardness of the frame of the IEEE 802.16e which is the legacy system, the transmission bandwidth, the sampling bandwidth, the FFT size, the subcarrier interval, and the like of the new system can follow the frame parameter of IEEE 802.16e. Also, the CP length is set to 1 / 8Tu, and 48 OFDM symbols are included in one frame, so that the present invention can be applied in a legacy support mode for supporting IEEE 802.16e. In Legacy Support Disabled Mode, the length of a new CP may be set to 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu, so that 43, 51, or 53 OFDM symbols May be included. For example, when one subframe is composed of six OFDM symbols, a frame having a length of 1/4 Tu is divided into 7 subframes and one residual OFDM symbol, and a frame having a length of 1/16 Tu is divided into 8 frames A subframe, three residual OFDM symbols, and a frame with a length of CP of 1 / 32Tu may be composed of 8 subframes and 5 residual OFDM symbols.

Here, CP is a copy of the final Tg, which is a useful symbol period, and can be expressed as a ratio to a useful symbol time (Tu).

Table 2 below shows the lengths of TTG and RTG in the TDD structure of the IEEE 802.16e standard. Hereinafter, the TTG may be expressed by terms such as a switching point or an idle frame. This is an example only and not a limitation. The switching point of the new system may be longer or shorter than the IEEE 802.16e standard.

Bandwidth 5M 10M 8.75M 7M 14M PS (ns) (= 4 / Fs) 714.286 357.142 400 500 250 TTG (μs) 148PS = 105.71 296PS = 105.71 218PS = 87.2 376PS = 188 752PS = 188 RTG (μs) 84PS = 60.00 168PS = 60.00 186PS = 74.4 120PS = 60 240PS = 60 TTG: RTG 1.76: 1 1.76: 1 1.17: 1 3.13: 1 3.13: 1

FIG. 5 illustrates a case where the DL / UL ratio is 5: 3, FIG. 6 illustrates the case where the DL / UL ratio is 6: 2, and FIG. 7 shows an example of a TDD frame structure in which the CP length is 1 / 8Tu when the DL / UL ratio is 7: 1.

Referring to FIGS. 4 to 7, a new TDD frame satisfying the backwardness is based on the existing TDD frame structure, the values of Table 1 and Table 2 above. That is, the new TDD frame has a length of 5 ms, the CP length is 1 / 8Tu, has a bandwidth of 10 MHz, and includes 48 OFDM symbols. In addition, basic control information such as preamble, FCH, and MAP can be defined according to the IEEE 802.16e standard. And TTG and RTG sizes as shown in Table 2 above.

4 to 7, one TDD frame is composed of 8 subframes. Here, a subframe is a basic unit of data allocation and scheduling, and is generally composed of six OFDM symbols. This is a value determined considering the bandwidth and pilot allocation pattern on the time axis when considering the size of the data and the characteristics of the radio channel allocated through encoding and modulation of the MAC and PHY. If one subframe is composed of 6 OFDM symbols, the DL / UL ratio can be efficiently set, and the number of OFDM symbols in the UL section can be adjusted to a multiple of 3 in a dual frame, . However, the number of OFDM symbols constituting one subframe is not limited to this.

A transmit / receive transition gap (TTG) is located between the DL region and the UL region, and a receive / transmit transition gap (RTG) is located between the UL region and the following frame. The TTG or RTG may include an idle time depending on the size of the CP to prevent intersymbol interference.

4, DL to 2364.86 μs including 23 OFDM symbols having a CP length of 1 / 8Tu from the start point of the frame is set as a DL interval, and idle time is set to 2364.86 μs from the TTG interval of Table 2 Up to a point of 2472.32 μs including a 107.46 μs section corresponding to a portion of time is set to a TTG section and a UL section is set up to 4940 μs including 24 OFDM symbols having a CP length of 1 / 8Tu from a point of 2472.32 μs, The RTG section is set from the point of 4940 μs to the end point of the frame including the 60 μs section corresponding to the RTG section of Table 2.

Referring to FIG. 5, a DL interval is set up to 2981.78 μs including 29 OFDM symbols having a CP length of 1 / 8Tu from the start point of the frame, and a TTG interval and a part of idle time , The TTG interval is set up to 3089.24 μs including the 107.46 μs interval, and the UL interval from the 3089.24 μs to the 4940 μs including 18 OFDM symbols having a CP length of 1 / 8Tu is set to the UL interval, The RTG section is set up to the last point of the frame including the 60-μs section corresponding to the RTG section of Table 2.

Referring to FIG. 6, the DL interval is set up to 3598.7 μs including 35 OFDM symbols having a CP length of 1/8 Tu from the start point of the frame, and from the point of 3598.7 μs to the TTG interval of Table 2 and a part of the idle time The TTG interval is set to 3706.16 μs including the 107.46 μs interval, and the UL interval is set to 4940 μs including 12 OFDM symbols having a CP length of 1 / 8Tu from the 3706.16 μs interval. The RTG section is set up to the last point of the frame including the 60-μs section corresponding to the RTG section of Table 2.

Referring to FIG. 7, a DL interval is set up to a point of 4215.62 μs including 41 OFDM symbols having a CP length of 1 / 8Tu from the start point of the frame, and a TTG interval and a part of idle time The TTG interval is set to 4323.08 μs including the 107.46 μs interval, and the UL interval from the 4323.08 μs to the 4940 μs including 6 OFDM symbols having a CP length of 1 / 8Tu is set to the UL interval, The RTG section is set up to the last point of the frame including the 60-μs section corresponding to the RTG section of Table 2.

In FIGS. 4 to 7, the RTG is set to 60.0 μs, the idle time is set to TTG, and the TTG is set to 107.46 μs. However, the TTG is set to 105.71 μs and the idle time is set to RTG And the RTG may be configured as 61.77 μs.

8 shows an example of an FDD frame structure having a CP length of 1/8 Tu.

Referring to FIG. 8, when the total length of a frame is 5 ms, 48 OFDM symbols are included in one frame. One frame is composed of 8 subframes, and one subframe is composed of 6 OFDM symbols. The idle time at the end of the frame is 64.64 μs as shown in Table 1 above.

FIGS. 4 to 8 show a TDD and FDD frame structure having a CP length of 1/8 Tu. However, when TDD frame structures having different CP length coexist in adjacent cells, mutual interference may occur due to mis-alignment of DL and UL transmissions. The present invention provides a TDD frame structure having CP lengths of various lengths, which do not cause mutual interference with a TDD frame having a CP length of 1 / 8Tu, and an FDD frame structure having commonality with the TDD frame.

≪ Frame structure for overlapping switching points between frames having different CP lengths >

9 is a diagram illustrating a TDD frame structure having a CP length of 1/4 Tu, 1 / 16Tu, or 1 / 32Tu according to an exemplary embodiment of the present invention when the DL / UL ratio is 4: 4.

Referring to FIG. 9, a reference frame has an existing structure as shown in FIG. 4, and has a total frame length of 5 ms and a CP length of 1/8 Tu, and is composed of 8 subframes.

The first TDD frame structure of this embodiment has a CP length of 1/4 Tu. The total length of the frame is 5 ms, the DL interval is set up to 2399.25 μs including 21 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set up to 2540.75 μs including 141.5 μs, which corresponds to a portion of 141.5 μs. The UL interval is set to 4940 μs including 21 OFDM symbols having a CP length of 1/4 Tu from 2540.75 μs, To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of five OFDM symbols, one residual OFDM symbol is further allocated to the DL interval, one remaining OFDM symbol is further allocated to the UL interval, and the remaining one remaining OFDM symbol is allocated to the TTG RTG section. That is, the last DL subframe consists of 6 OFDM symbols in the FDD, and the last OFDM symbol of this subframe is punctured and converted into a subframe of 5 OFDM symbols in the TDD due to the TTG interval. In the first TDD frame structure of FIG. 9, the first subframe of the DL interval and the last subframe of the UL interval are composed of six OFDM symbols, but any subframe belonging to the DL interval may be replaced by six OFDM symbols, and may be composed of six OFDM symbols instead of any one of the last frames belonging to the UL section. Also, the DL section is composed of a plurality of subframes including five OFDM symbols and another independent OFDM symbol, and the UL section is composed of a plurality of subframes including five OFDM symbols and another independent OFDM symbol You may. The configuration of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

The second TDD frame structure of this embodiment has a CP length of 1/16 Tu. The total length of the frame is 5 ms, the DL interval is set to 2427.8 μs including 25 OFDM symbols having a CP length of 1/16 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 2511.6 μs including 84.5 μs, which corresponds to a portion of the time. The UL interval is set to 4940 μs including 25 OFDM symbols having a CP length of 1 / 16Tu from 2511.6 μs, To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, three remaining OFDM symbols remain, one OFDM symbol of the three remaining OFDM symbols is further allocated to the DL section, and one OFDM symbol is further allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. That is, the last DL subframe is composed of 7 OFDM symbols in FDD, and the last OFDM symbol of this subframe is punctured and converted into a subframe of 6 OFDM symbols in TDD due to the TTG interval. In the second TDD frame structure of FIG. 9, the first subframe of the DL section is composed of 7 OFDM symbols, and the last subframe of the UL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first frame, and 7 OFDM symbols may be configured instead of any one of the last frames belonging to the UL section. Also, the DL section is composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol, and the UL section is composed of a plurality of subframes each consisting of six OFDM symbols and another independent OFDM symbol You may. The configuration of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

The third TDD frame structure of this embodiment has a CP length of 1/32 Tu. The total length of the frame is 5 ms, the DL interval is set to 2450.76 μs including 26 OFDM symbols having a CP length of 1 / 32Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set up to 2583.5 μs including 132.42 μs, which corresponds to a part of the time. The UL interval is set to 4940 μs including 25 OFDM symbols having a CP length of 1 / 32Tu from 2583.5 μs. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, five remaining OFDM symbols remain, two OFDM symbols of five remaining OFDM symbols are allocated to the DL section, and one OFDM symbol is further allocated to the UL section And the remaining two OFDM symbols are further allocated to the TTG and RTG periods. In the third TDD frame structure of FIG. 9, the first subframe and the last subframe of the DL section are composed of 7 OFDM symbols, and the last subframe of the UL section is composed of 7 OFDM symbols. However, two of the subframes belonging to the DL section are composed of 7 OFDM symbols instead of the first and last subframes, and one of the subframes belonging to the UL section is composed of 7 OFDM symbols instead of the last UL subframe . In addition, the DL section is composed of a plurality of sub-frames composed of six OFDM symbols and the remaining two independent OFDM symbols, and the UL section is composed of a plurality of sub-frames composed of six OFDM symbols and another independent OFDM symbol You may. The configuration of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

As shown in FIG. 9, when a TDD frame is formed, mutual interference does not occur even when a frame structure having different CP length coexists in adjacent cells. That is, the UL interval of a frame having a CP length of 1 / 8Tu and the UL interval of a frame having a CP length of 1 / 4Tu, 1 / 16Tu or 1 / 32Tu, The DL sections of a frame having a CP length of 1/4 Tu, 1/16 Tu or 1 / 32Tu are not overlapped, and mutual interference does not occur.

10 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an embodiment of the present invention when the DL / UL ratio is 5: 3 .

Referring to FIG. 10, a reference frame has an existing structure as shown in FIG. 5, and has a total frame length of 5 ms and a CP length of 1 / 8Tu, and is composed of 8 subframes.

The first TDD frame structure of this embodiment has a CP length of 1/4 Tu. The total length of the frame is 5 ms, the DL interval is set up to 2856.25 μs including 25 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG section is set up to 2997.75 μs including the 141.5 μs section, which is equivalent to a part, and the UL section is set to the 4940 μs section including 17 OFDM symbols having a CP length of 1/4 Tu from the 2997.75 μs section, To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, one residual OFDM symbol is further allocated to the DL section, the first subframe of the UL section is composed of five OFDM symbols, and the first One OFDM symbol located in front of the subframe is punctured. In the first TDD frame structure of FIG. 10, the first subframe of the DL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first subframe. Also, the DL section may be composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol. Such a subframe structure is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

As another example, in a TDD frame structure with a CP length of 1 / 4Tu, if one subframe is composed of five OFDM symbols, one remaining OFDM symbol is further allocated to the DL section, and one remaining OFDM symbol is allocated to the UL section And the remaining one remaining OFDM symbol may be allocated to the TTG period. This structure is the same as the case of 1/4 Tu described in FIG. 9 in which the DU / UL ratio is expressed as 4: 4.

The second TDD frame structure of this embodiment has a CP length of 1/16 Tu. The total length of the frame is 5 ms, the DL interval is set to 3010.41 μs including 31 OFDM symbols having a CP length of 1/16 Tu from the start point of the frame, and the TTG interval and the idle time of Table 2 are set to 3010.41 μs The TTG interval is set to 3094.91 μs including 84.5 μs, which corresponds to a portion of the time, and the UL interval is set to 4940 μs including 19 OFDM symbols having a CP length of 1 / 16Tu from 3094.91 μs. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, three remaining OFDM symbols remain, one OFDM symbol of the three remaining OFDM symbols is further allocated to the DL section, and one OFDM symbol is further allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. That is, the last DL subframe is composed of 7 OFDM symbols in FDD, and the last OFDM symbol of this subframe is punctured and converted into a subframe of 6 OFDM symbols in TDD due to the TTG interval. In the second TDD frame structure of FIG. 10, the first subframe of the DL section is composed of 7 OFDM symbols, and the last subframe of the UL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first subframe, and one subframe belonging to the UL section may be composed of 7 OFDM symbols instead of the last subframe. Also, the DL section is composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol, and the UL section is composed of a plurality of subframes each consisting of six OFDM symbols and another independent OFDM symbol You may. The remaining one OFDM symbol may be a subframe consisting of six OFDM symbols or a symbol (seventh or last symbol) of a subframe composed of seven OFDM symbols. Such a subframe structure is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

The third TDD frame structure of this embodiment has a CP length of 1/32 Tu. The total length of the frame is 5 ms, the DL interval is set to 3016.32 μs including 32 OFDM symbols having a CP length of 1 / 32Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set up to 3054.80 μs including the 38.48 μs interval, and the UL interval is set to 4940 μs including 20 OFDM symbols having a CP length of 1 / 32Tu from the 3054.80 μs interval. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, five remaining OFDM symbols remain, two OFDM symbols of the five remaining OFDM symbols are allocated to the DL section, and two OFDM symbols are allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. In the third TDD frame structure of FIG. 10, the first subframe and the last subframe of the DL section are composed of seven OFDM symbols, and the first subframe and the last subframe of the UL section are composed of seven OFDM symbols have. However, two of the subframes belonging to the DL section are composed of 7 OFDM symbols instead of the first and last DL subframes, and two of the subframes belonging to the UL section are composed of 7 OFDM symbols instead of the first and last UL subframes . The DL section is composed of a plurality of subframes each consisting of six OFDM symbols and the remaining two independent OFDM symbols, and the UL section is composed of a plurality of subframes each consisting of six OFDM symbols and two independent OFDM symbols You may. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

If the TTG interval is longer than 38.48 μs, one of the additional OFDM symbols allocated to the DL interval or the UL interval may be further allocated for the TTG interval. For example, one of the OFDM symbols that have been additionally allocated to the UL section may be further allocated for the TTG section, and the TTG section may be set to 132.74 μs.

When a TDD frame is formed as shown in FIG. 10, mutual interference does not occur even when a frame structure having different CP length coexists in adjacent cells. That is, the UL interval of a frame having a CP length of 1 / 8Tu and the UL interval of a frame having a CP length of 1 / 4Tu, 1 / 16Tu or 1 / 32Tu, The DL sections of a frame having a CP length of 1/4 Tu, 1/16 Tu or 1 / 32Tu are not overlapped, and mutual interference does not occur.

11 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an exemplary embodiment of the present invention when the DL / UL ratio is 6: 2 .

Referring to FIG. 11, a reference frame has a total frame length of 5 ms and a CP length of 1/8 Tu, as in the conventional structure of FIG. 6, and consists of 8 subframes.

The first TDD frame structure of this embodiment has a CP length of 1/4 Tu. The total length of the frame is 5ms, the DL interval is set up to 3541.8 μs including 31 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 3683.25 microseconds including 141.45 microseconds, which corresponds to a portion of 141.45 microseconds, and the UL interval is set to 4940 microseconds including 11 OFDM symbols having a CP length of 1/4 Tu from 3683.25 microseconds. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, one residual OFDM symbol is further allocated to the DL interval, the first subframe of the UL interval is composed of five OFDM symbols, and the first subframe of the UL interval And puncturing one OFDM symbol located in front of the OFDM symbol. In the first TDD frame structure of FIG. 11, the first subframe of the DL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first subframe. Also, the DL section may be composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the uplink section may be composed of an arbitrary number of OFDM symbols, and the subframes may have different sizes .

As another example, in a TDD frame structure with a CP length of 1 / 4Tu, if one subframe is composed of five OFDM symbols, one remaining OFDM symbol is further allocated to the DL section, and one remaining OFDM symbol is allocated to the UL section And the remaining one remaining OFDM symbol may be allocated to the TTG period. This structure is the same as the case of 1/4 Tu described in FIG. 9 in which the DU / UL ratio is expressed as 4: 4.

The second TDD frame structure of this embodiment has a CP length of 1/16 Tu. The total length of the frame is 5 ms, the DL interval is set up to 3593.07 μs including 37 OFDM symbols having a CP length of 1/16 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 3677.57 μs including 84.5 μs, which corresponds to a portion, and is set to the UL interval from the point of 3677.57 μs to 4940 μs including 13 OFDM symbols having a CP length of 1 / 16Tu. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, three remaining OFDM symbols remain, one OFDM symbol of the three remaining OFDM symbols is further allocated to the DL section, and one OFDM symbol is further allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. That is, the last DL subframe is composed of 7 OFDM symbols in FDD, and the last OFDM symbol of this subframe is punctured and converted into a subframe of 6 OFDM symbols in TDD due to the TTG interval. In the second TDD frame structure of FIG. 11, the first subframe of the DL section is composed of 7 OFDM symbols, and the last subframe of the UL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of seven OFDM symbols instead of the first subframe, and one subframe belonging to the UL section may be composed of seven OFDM symbols instead of the last subframe. Also, the DL section is composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol, and the UL section is composed of a plurality of subframes each consisting of six OFDM symbols and another independent OFDM symbol You may. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and each subframe may have a different size.

The third TDD frame structure of this embodiment has a CP length of 1/32 Tu. The total length of the frame is 5 ms, the DL section is set to 3581.88 μs including 38 OFDM symbols having a CP length of 1 / 32Tu from the start point of the frame, and the TTG section and the idle time The TTG interval is set to 3620.36 μs including 38.48 μs which corresponds to a part of the time, and the UL interval is set to 4940 μs including 14 OFDM symbols having a CP length of 1 / 32Tu from the 3620.36 μs. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, five remaining OFDM symbols remain, two OFDM symbols of the five remaining OFDM symbols are allocated to the DL section, and two OFDM symbols are allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. In the third TDD frame structure of FIG. 11, the first subframe and the last subframe of the DL section are composed of 7 OFDM symbols. However, any two subframes belonging to the DL section may be composed of 7 OFDM symbols instead of the first and last subframes. The DL section is composed of a plurality of subframes each consisting of six OFDM symbols and the remaining two independent OFDM symbols, and the UL section is composed of a plurality of subframes each consisting of six OFDM symbols and two independent OFDM symbols You may. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and each subframe may have a different size.

Also, if the TTG interval requires a longer interval than 38.48 [mu] s, one of the OFDM symbols that was additionally allocated to the DL interval or the UL interval may be further allocated for the TTG interval. For example, one of the OFDM symbols that have been additionally allocated to the UL section may be further allocated for the TTG section, and the TTG section may be set to 132.74 μs.

When the TDD frame is configured as shown in FIG. 11, mutual interference does not occur even when a frame structure having different CP length coexists in adjacent cells. That is, the UL interval of a frame having a CP length of 1 / 8Tu and the UL interval of a frame having a CP length of 1 / 4Tu, 1 / 16Tu or 1 / 32Tu, The DL sections of a frame having a CP length of 1/4 Tu, 1/16 Tu or 1 / 32Tu are not overlapped, and mutual interference does not occur.

12 is a diagram illustrating a TDD frame structure having a CP length of 1/4 Tu, 1 / 16Tu, or 1 / 32Tu in comparison with a 1 / 8Tu CP length according to an embodiment of the present invention when the DL / UL ratio is 7: 1 .

Referring to FIG. 12, the reference frame has a total frame length of 5 ms and a CP length of 1/8 Tu, as in the conventional structure of FIG. 7, and consists of 8 subframes.

The first TDD frame structure of this embodiment has a CP length of 1/4 Tu. The total length of the frame is 5 ms, the DL interval is set to 4227.25 μs including 37 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 4368.75 μs including 141.5 μs, which corresponds to a portion of 141.5 μs, and the UL interval is set to 4940 μs including 5 OFDM symbols having a CP length of 1 / 4Tu from 4368.75 μs. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, one residual OFDM symbol is further allocated to the DL section, the first subframe of the UL section is composed of five OFDM symbols, and the first One OFDM symbol located in front of the subframe is punctured. In the first TDD frame structure of FIG. 12, the first subframe of the DL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first subframe. Also, the DL section may be composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

As another example, in a TDD frame structure with a CP length of 1 / 4Tu, if one subframe is composed of five OFDM symbols, one remaining OFDM symbol is further allocated to the DL section, and one remaining OFDM symbol is allocated to the UL section And the remaining one remaining OFDM symbol may be allocated to the TTG and RTG periods. This structure is the same as the case of 1/4 Tu described in FIG. 9 in which the DU / UL ratio is expressed as 4: 4.

The second TDD frame structure of this embodiment has a CP length of 1/16 Tu. The total length of the frame is 5 ms, the DL interval is set up to 4175.73 μs including 43 OFDM symbols having a CP length of 1/16 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set up to 4260.23μs including 84.5μs corresponding to a portion, and the UL interval is set up to 4940μs including 7 OFDM symbols having a CP length of 1 / 16Tu from 4260.23μs, and the UL interval is set to 4940μs To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of a plurality of OFDM symbols, three remaining OFDM symbols remain, one OFDM symbol of the three remaining OFDM symbols is further allocated to the DL section, and one OFDM symbol is further allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. That is, the last DL subframe is composed of 7 OFDM symbols in FDD, and the last OFDM symbol of this subframe is punctured and converted into a subframe of 6 OFDM symbols in TDD due to the TTG interval. In the second TDD frame structure of FIG. 12, the first subframe of the DL section is composed of 7 OFDM symbols. However, one subframe belonging to the DL section may be composed of 7 OFDM symbols instead of the first subframe. Also, the DL section may be composed of a plurality of subframes including six OFDM symbols and another independent OFDM symbol. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of arbitrary OFDM symbols, and the subframes may have different sizes.

The third TDD frame structure of this embodiment has a CP length of 1/32 Tu. The total length of the frame is 5ms and the DL section up to 4241.7 μs including 45 OFDM symbols having a CP length of 1 / 32Tu from the start point of the frame is set as the DL section and the TTG section and the idle time The TTG interval is set to 4280.18μs including the 38.48μs interval, and the UL interval is set to 4940μs including 7 OFDM symbols having a CP length of 1 / 32Tu from the 4280.18μs interval. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval. Therefore, if one subframe is composed of six OFDM symbols, five remaining OFDM symbols remain, three OFDM symbols of the five remaining OFDM symbols are further allocated to the DL section, and one OFDM symbol is allocated to the UL section And the remaining one OFDM symbol is further allocated to the TTG and RTG periods. In the third TDD frame structure of FIG. 12, the first sub-frame of the DL interval and the sixth and seventh sub-frames are composed of 7 OFDM symbols. However, any three subframes belonging to the DL section may be composed of seven OFDM symbols instead of the three subframes. In addition, the DL section may be composed of a plurality of sub-frames of six OFDM symbols and the remaining three independent OFDM symbols, and the UL section may be composed of a sub-frame of six OFDM symbols and another independent OFDM symbol have. The structure of such a subframe is merely an example. That is, the subframes belonging to the DL section may be composed of an arbitrary number of OFDM symbols, the subframes belonging to the UL section may be composed of any number of OFDM symbols, and the subframes may have different sizes.

Also, if the TTG interval requires a longer interval than 38.48 [mu] s, one of the OFDM symbols that was additionally allocated to the DL interval or the UL interval may be further allocated for the TTG interval. For example, one of the OFDM symbols that have been additionally allocated to the UL section may be further allocated for the TTG section, and the TTG section may be set to 132.74 μs.

When the TDD frame is configured as shown in FIG. 12, mutual interference does not occur even when a frame structure having different CP length coexists in adjacent cells. That is, the UL interval of a frame having a CP length of 1 / 8Tu and the UL interval of a frame having a CP length of 1 / 4Tu, 1 / 16Tu or 1 / 32Tu, The DL sections of a frame having a CP length of 1/4 Tu, 1/16 Tu or 1 / 32Tu are not overlapped, and mutual interference does not occur.

Table 3 below summarizes the features shown in FIG. 9, showing a frame structure according to an embodiment of the present invention that coexist with existing frame structures and have different CP lengths.

Parameters Values or Features DL / UL Ratio with a CP of 1 / 8Tu 4: 4 5: 3 6: 2 7: 1 4: 4 5: 3 6: 2 7: 1 4: 4 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 4Tu 1 / 16Tu 1 / 32Tu Total No.of Symbols per 5ms Frame (Nsym) 43 51 53 No.of Residue Symbols (= Nsym mod 6) One
(In case of Nsym mod 5, 3 Residue Symbols) 3 5 Positions of Residue Symbols One in DL
(In case of Nsym mod 5, One in DL, One in UL and One in TTG) One in DL, One in UL, and One in TTG Two in DL, Two in UL, and One in TTG
(+) In case of 7: 1, Three in DL, One in UL, and One in TTG
(+) In case of 4: 4,
Two in DL, One in UL, and Two in TTG No.of Punctured Symbols in Regular Subframes One
(In case of Nsym mod 5, 0 Punctured Symbol) 0 0 Size of DL (μs) 2399.25
(Nsym mod 5)
2856.25 3541.8 4227.25 2427.8 3010.41 3593.07 4175.73 2450.76 3016.32 3581.88
4241.7 Size of UL (μs) 2399.25
(Nsym mod 5)
1942.25
1256.75 571.25 2428.4 1845.09 1262.43 679.77 2356.5 1885.2 1319.64 659.82 No.of Regular Subframes 5
(In case of Nsym mod 5, 6 Regular Subframes) 6 4 Size of Irregular Subframes (*) 5 and 7 OFDM Symbols
(In case of Nsym mod 5, 6 OFDM symbols) 7 OFDM Symbols 7 OFDM Symbols No.of Irregular Subframes (*) 2 2 4

In the TDD frame structure with a DL / UL ratio of 4: 4 and a CP length of 1/4 Tu in Table 3, it is assumed that one subframe is composed of five OFDM symbols. In the TDD frame structure of 1 / 32Tu, TTG One OFDM symbol is further allocated to the interval. In addition, in the TDD frame structure with a DL / UL ratio of 7: 1 and a CP length of 1 / 32Tu, only one subframe is allocated for the DL interval, so that the remaining OFDM symbols are further allocated to the UL interval. In Table 3, the last two lines with the (*) mark differ depending on how many OFDM symbols one subframe is basically composed. When the configuration of Table 3 is applied to the system, one symbol may be further punctured in the DL section or the UL section, if necessary.

≪ Subframe type according to the number of OFDM symbols included in the subframe >

FIGS. 13 to 16 are diagrams illustrating the following: 1) a TDD frame structure of FIGS. 9 to 12 coexisting with a TDD frame structure having a CP length of 1/8 Tu in an adjacent cell and having a different CP length; and 2) Gt; FDD < / RTI > A TDD frame and an FDD frame having a CP length of 1/4 Tu, 1 / 16Tu, or 1 / 32Tu are composed of three types of subframes.

Hereinafter, a subframe type consisting of six OFDM symbols is referred to as SFT-1 (Subframe Type-1), a subframe type composed of five OFDM symbols is referred to as SFT-2, a subframe type composed of seven OFDM symbols is referred to as SFT-3 . Here, the SFT-3 type subframe has one OFDM symbol added to the SFT-1 type subframe, and the position where the one OFDM symbol is added is before, after, or after the SFT-1 type subframe. It can be any intermediate position. The added one OFDM symbol may be used for control information such as a preamble or a sounding, or may be used for data.

13 is a diagram illustrating a TDD frame structure having a CP length of 1 / 4Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention. 13, all the remaining subframes except the SFT-2 and SFT-3 type subframes are SFT-1 type subframes.

Referring to FIG. 13, in the first TDD frame structure of the present embodiment, the DL / UL ratio is 4: 3 and the CP length is 1 / 4Tu. The total length of the frame is 5 ms, the DL interval is set up to 2856.25 μs including 25 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG section is set up to 2997.75 μs including the 141.5 μs section, which is equivalent to a part, and the UL section is set to the 4940 μs section including 17 OFDM symbols having a CP length of 1/4 Tu from the 2997.75 μs section, To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval.

Therefore, the DL section is composed of three SFT-1 subframes and one SFT-3 subframe, and the UL section is composed of two SFT-1 subframes and one SFT-2 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the second TDD frame structure of this embodiment, the DL / UL ratio is 5: 2 and the CP length is 1 / 4Tu. The total length of the frame is 5ms, the DL interval is set up to 3541.8 μs including 31 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 3683.25 microseconds including 141.45 microseconds, which corresponds to a portion of 141.45 microseconds, and the UL interval is set to 4940 microseconds including 11 OFDM symbols having a CP length of 1/4 Tu from 3683.25 microseconds. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval.

Therefore, the DL section is composed of four SFT-1 subframes and one SFT-3 subframe, and the UL section is composed of one SFT-1 subframe and one SFT-2 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the third TDD frame structure of this embodiment, the DL / UL ratio is 6: 1 and the CP length is 1/4 Tu. The total length of the frame is 5 ms, the DL interval is set to 4227.25 μs including 37 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set to 4368.75 μs including 141.5 μs, which corresponds to a portion of 141.5 μs, and the UL interval is set to 4940 μs including 5 OFDM symbols having a CP length of 1 / 4Tu from 4368.75 μs. To the end point of the frame including the 60-μs interval corresponding to the RTG interval of Table 2 is set as the RTG interval. Each point can be changed according to the TTG interval and the RTG interval.

Therefore, the DL section is composed of five SFT-1 subframes and one SFT-3 subframe, and the UL section is composed of one SFT-2 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

When a TDD frame is configured as described above, a frame structure having a CP length of 1 / 8Tu and a DL / UL switching section coincide with each other, and even when a system having a CP length of 1 / 8Tu exists in an adjacent cell, Interference between link transmissions can be minimized.

Regardless of the DL / UL ratio, the DL interval includes one SFT-3 type subframe. In FIG. 13, the first subframe # 1 of the DL section is composed of SFT-3 type subframes, but this is only an example. That is, if the DL / UL ratio is 4: 3, the SFT-3 type subframe may be located in one of # 1, # 2, # 3 and # 4, and DL / UL ratio is 5: The SFT-3 type subframe may be located at one of # 1, # 2, # 3, # 4 and # 5. If the DL / UL ratio is 6: 1, May be located at one of the positions # 1, # 2, # 3, # 4, # 5, and # 6.

Also, regardless of the DL / UL ratio, the UL interval includes one SFT-2 type subframe. In FIG. 13, the first subframe of the UL section is composed of SFT-2 type subframes, but this is merely an example. That is, if the DL / UL ratio is 4: 3, the SFT-2 type subframe may be located in one of # 5, # 6 and # 7. If the DL / UL ratio is 5: 2, The 2-type subframe may be located in one of # 6 and # 7, and the SFT-2 type subframe may be located at # 7 when the DL / UL ratio is 6: 1.

Next, the FDD frame structure includes a pivot subframe. The pivot subframe is a subframe at a position corresponding to the TTG section of the TDD frame in order to maintain commonality with the TDD frame. When the CP length is 1 / 4Tu, the pivot subframe is a SFT-1 type subframe. When the DL / UL ratio is 4: 3, since the TTG section in the TDD frame is located between # 4 and # 5, the pivot subframe in the FDD frame can be located at # 5. When the DL / UL ratio is 5: 2, since the TTG section in the TDD frame is located between # 5 and # 6, the pivot subframe in the FDD frame can be located at # 6. Also, when the DL / UL ratio is 6: 1, the TTG section in the TDD frame is located between # 6 and # 7, so that the pivot subframe in the FDD frame can be located at # 7. In order to maintain commonality with the TDD frame, one SFT-3 type subframe is positioned at a position prior to the pivot subframe. That is, if the DL / UL ratio is 4: 3, the SFT-3 type subframe may be located in one of # 1, # 2, # 3 and # 4, and DL / UL ratio is 5: The SFT-3 type subframe may be located at one of # 1, # 2, # 3, # 4 and # 5. If the DL / UL ratio is 6: 1, May be located at one of the positions # 1, # 2, # 3, # 4, # 5, and # 6.

13, the pivot subframe is located in subframes # 5, # 6 and # 7, but this is only an example. Other FDD frames with pivot subframes in different locations can be considered equally.

FIG. 13 shows a TDD frame structure having a CP length of 1/4 Tu, in which a basic subframe is composed of SFT-1 type subframes. However, it is also possible to construct the basic subframe into SFT-2 type subframes.

FIG. 14 is a diagram illustrating a TDD frame having a basic sub-frame composed of SFT-2 subframes having a CP length of 1/4 Tu and an FDD frame having a commonality with the TDD frame according to an embodiment of the present invention. 14, the remaining subframes except the SFT-1 type subframe are SFT-2 type subframes.

Referring to FIG. 14, in the first TDD frame structure of the present embodiment, the DL / UL ratio is 4: 4 and the CP length is 1 / 4Tu, and the basic subframe is the SFT-2 type subframe. This structure is the same as the TDD frame structure in which the CP length in Fig. 9 is 1 / 4Tu. Therefore, the DL section is composed of one SFT-1 subframe and three SFT-2 subframes, and the UL section is composed of one SFT-1 subframe and three SFT-2 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the second TDD frame structure of the present embodiment, the DL / UL ratio is 5: 3, the CP length is 1 / 4Tu, and the basic subframe is the SFT-2 type subframe. The total length of the frame is 5 ms, the DL interval is set up to 2970.5 μs including 26 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time The TTG interval is set up to 3112μs including 141.5μs, which corresponds to a portion of 141.5μs, and the UL interval is set to 4940μs including 16 OFDM symbols having a CP length of 1/4Tu from 3112μs. The RTG section is set up to the last point of the frame including the 60 占 퐏 interval corresponding to the RTG interval of 2. Each point can be changed according to the TTG interval and the RTG interval.

Therefore, the DL section is composed of one SFT-1 subframe and four SFT-2 subframes, and the UL section is composed of one SFT-1 subframe and two SFT-2 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the third TDD frame structure of this embodiment, the DL / UL ratio is 6: 2, the CP length is 1 / 4Tu, and the basic subframe is a SFT-2 type subframe. This structure is the same as the frame structure with the CP length of 1/4 Tu in Fig. Therefore, the DL section is composed of one SFT-1 subframe and five SFT-2 subframes, and the UL section is composed of one SFT-1 subframe and one SFT-2 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the fourth TDD frame structure of this embodiment, the DL / UL ratio is 7: 1 and the CP length is 1 / 4Tu, and the basic subframe is the SFT-2 type subframe. The total length of the frame is 5 ms, the DL interval is set up to 4113 μs including 36 OFDM symbols having a CP length of 1/4 Tu from the start point of the frame, and the TTG interval and the idle time of Table 2 are set to 4113 μs The TTG interval is set to 4254.5 μs including the corresponding 141.5 μs interval, the UL interval is set to 4940 μs including 6 OFDM symbols having a CP length of 1 / 4Tu from 4254.5 μs, The RTG section is set up to the last point of the frame including the 60 占 퐏 interval corresponding to the RTG interval of 2. Each point can be changed according to the TTG interval and the RTG interval.

Therefore, the DL section is composed of one SFT-1 subframe and six SFT-2 subframes, and the UL section is composed of one SFT-1 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

When a TDD frame is configured as described above, a frame structure having a CP length of 1 / 8Tu and a DL / UL switching section coincide with each other, and even when a system having a CP length of 1 / 8Tu exists in an adjacent cell, Interference between link transmissions can be minimized.

If the basic subframe is composed of SFT-2 type subframes, the DL section includes one SFT-1 type subframe regardless of the DL / UL ratio. When the DL / UL ratio is 4: 4, the SFT-1 type subframe may be located in one of # 1, # 2, # 3 and # 1 type subframe may be located in one of # 1, # 2, # 3, # 4 and # 5. When the DL / UL ratio is 6: 2, the SFT- # 1, # 2, # 3, # 4, # 5 and # 6 and the DL / UL ratio is 7: # 3, # 4, # 5, # 6, and # 7.

If the basic subframe is composed of SFT-2 type subframes, the UL interval includes one SFT-1 type subframe regardless of the DL / UL ratio. When the DL / UL ratio is 4: 4, the SFT-1 type subframe may be located in one of # 5, # 6, # 7 and # 8. If the DL / UL ratio is 5: -1 type subframe may be located in one of # 6, # 7, and # 8. When the DL / UL ratio is 6: 2, the SFT-1 type subframe is one of # 7 and # 8 And if the DL / UL ratio is 7: 1, the SFT-1 type subframe may be located at # 8.

Next, if the CP length is 1 / 4Tu and the basic subframe is an SFT-2 subframe, the pivot subframe may be located at a position corresponding to the TTG duration of the TDD frame. Here, the pivot subframe is the SFT-1 type subframe. When the DL / UL ratio is 4: 4, the TTG section in the TTD frame is located between # 4 and # 5, so that the pivot subframe in the FDD frame can be located at # 4 or # 5. When the DL / UL ratio is 5: 3, the TTG section in the TDD frame is located between # 5 and # 6, so that the pivot subframe in the FDD frame can be located at # 5 or # 6. When the DL / UL ratio is 6: 2, since the TTG section in the TDD frame is located between # 6 and # 7, the pivot subframe in the FDD frame can be located at # 6 or # 7. Also, when the DL / UL ratio is 7: 1, the TTG section in the TDD frame is located between # 7 and # 8, so that the pivot subframe in the FDD frame can be located at # 7 or # 8. However, since the UL section includes one SFT-1 type subframe, the position of the pivot subframe is preferably # 7 when the DL / UL ratio is 7: 1.

In order to maintain commonality with the TDD frame, one SFT-1 type subframe is positioned before the pivot subframe, and one SFT-1 type subframe is positioned after the pivot subframe. That is, when the DL / UL ratio is 4: 4, the subframe of the SFT-1 type excluding the pivot subframe is located at one of # 1, # 2 and # 3 and # 5 # 6, # 7 and # 8, or one of # 1, # 2, # 3 and # 4 and # 6, # 7 and # 8 can be located in one place. When the DL / UL ratio is 5: 3, the subframe of the SFT-1 type excluding the pivot subframe is located at one of # 1, # 2, # 3, and # 4 and # 6, # 7 and # 8, or when one of the pivot subframes is located at # 6, one of # 1, # 2, # 3, # 4 and # It can be located in one place. When the DL / UL ratio is 6: 2, the subframe of the SFT-1 type excluding the pivot subframe is one of # 1, # 2, # 3, # 4, and # 5 Frame and one position in # 7 and # 8, or one of # 1, # 2, # 3, # 4, # 5 and # Can be located. When the DL / UL ratio is 7: 1, the subframe of the SFT-1 type except for the pivot subframe is # 1, # 2, # 3, # 4, # 5 or # 6 Can be placed in one of the two positions # 1, # 2, # 3, # 4, # 5, # 6, and # 7 if the pivot subframe is located at # 8. have.

14, the pivot subframe is located in subframes # 5, # 6, # 7 and # 8, but this is only an example. Other FDD frames with pivot subframes in different locations can be considered equally.

15 is a diagram illustrating a TDD frame structure having a CP length of 1 / 16Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention. 15, the remaining subframes except the SFT-3 type subframe are SFT-1 type subframes.

Referring to FIG. 15, in the first TDD frame structure of the present embodiment, the DL / UL ratio is 4: 4 and the CP length is 1 / 16Tu. This structure is the same as the frame structure in which the CP length of FIG. 9 is 1 / 16Tu. Therefore, the DL section is composed of one SFT-3 subframe and three SFT-1 subframes, and the UL section is composed of one SFT-3 subframe and three SFT-1 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the second TDD frame structure of this embodiment, the DL / UL ratio is 5: 3 and the CP length is 1/16 Tu. This structure is the same as the frame structure with the CP length of 1 / 16Tu in Fig. Therefore, the DL section is composed of one SFT-3 subframe and four SFT-1 subframes, and the UL section is composed of one SFT-3 subframe and two SFT-1 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the third TDD frame structure of this embodiment, the DL / UL ratio is 6: 2 and the CP length is 1/16 Tu. This structure is the same as the frame structure with the CP length of 1 / 16Tu in Fig. Therefore, the DL section is composed of one SFT-3 subframe and five SFT-1 subframes, and the UL section is composed of one SFT-3 subframe and one SFT-1 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the fourth TDD frame structure of this embodiment, the DL / UL ratio is 7: 1 and the CP length is 1/16 Tu. This structure is the same as the frame structure in which the CP length is 1 / 16Tu in Fig.

Therefore, the DL section is composed of one SFT-3 subframe and six SFT-1 subframes, and the UL section is composed of one SFT-3 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

When a TDD frame is configured as described above, a frame structure having a CP length of 1 / 8Tu and a DL / UL switching section coincide with each other, and even when a system having a CP length of 1 / 8Tu exists in an adjacent cell, Interference between link transmissions can be minimized.

Regardless of the DL / UL ratio, the DL interval includes one SFT-3 type subframe. In FIG. 15, the first subframe # 1 of the DL section is composed of SFT-3 type subframes, but this is merely an example. That is, when the DL / UL ratio is 4: 4, the SFT-3 type subframe may be located in one of # 1, # 2, # 3 and # 4, and DL / UL ratio is 5: The SFT-3 type subframe may be located in one of # 1, # 2, # 3, # 4 and # 5. If the DL / UL ratio is 6: 2, The SFT-3 type subframe may be located at any one of # 1, # 2, # 3, # 4, # 5 and # 6, 2, # 3, # 4, # 5, # 6, and # 7.

Also, regardless of the DL / UL ratio, the UL section includes one SFT-3 type subframe. In FIG. 15, the last subframe # 8 of the UL section is composed of SFT-3 type subframes, but this is only an example. That is, when the DL / UL ratio is 4: 4, the SFT-3 type subframe may be located in one of # 5, # 6, # 7 and # 8, and DL / UL ratio is 5: The SFT-3 type subframe may be located in one of # 6, # 7 and # 8. If the DL / UL ratio is 6: 2, the SFT-3 type subframe is # 7 and # 8 And if the DL / UL ratio is 7: 1, the SFT-3 type subframe may be located at # 8.

Next, referring to the FDD frame structure, the FDD frame includes one pivot subframe. As shown in FIG. 15, the pivot subframe may be a SFT-3 type subframe. Also, the pivot subframe may be located at a position corresponding to the TTG section of the TDD frame. That is, when the DL / UL ratio is 4: 4, since the TTG section in the TDD frame is located between # 4 and # 5, the pivot subframe in the FDD frame can be located at # 4 or # 5. When the DL / UL ratio is 5: 3, the TTG section in the TDD frame is located between # 5 and # 6, so that the pivot subframe in the FDD frame can be located at # 5 or # 6. Also, when the DL / UL ratio is 6: 2, since the TTG section in the TDD frame is located between # 6 and # 7, the pivot subframe in the FDD frame can be located at # 6 or # 7. Also, when the DL / UL ratio is 7: 1, the TTG section in the TDD frame is located between # 7 and # 8, so that the pivot subframe in the FDD frame can be located at # 7 or # 8. However, since the UL section includes one SFT-3 type subframe, the position of the pivot subframe is preferably # 7 when the DL / UL ratio is 7: 1.

 In order to maintain commonality with the TDD frame, one SFT-3 type subframe is positioned before the pivot subframe, and one SFT-3 type subframe is positioned after the pivot subframe. That is, when the DL / UL ratio is 4: 4, the subframe of the SFT-3 type except for the pivot subframe is one of # 1, # 2 and # 3 and # 5 # 6, # 7 and # 8, or one of # 1, # 2, # 3 and # 4 and # 6, # 7 and # 8 can be located in one place. When the DL / UL ratio is 5: 3, the SFT-3 type subframe excluding the pivot subframe is located at one of # 1, # 2, # 3 and # 4 (Preferably # 8) of # 6, # 7 and # 8 or # 1, # 2, # 3 and # 4 when the pivot subframe is located at # 6 And # 5, and one of # 7 and # 8. When the DL / UL ratio is 6: 2, the subframe of the SFT-3 type excluding the pivot subframe is one of # 1, # 2, # 3, # 4, and # 5 Position in # 7 and # 8, or one of # 1, # 2, # 3, # 4, # 5, and # 6 and # 8 if the pivot subframe is located at # 7 can do. When the DL / UL ratio is 7: 1, the subframe of the SFT-3 type excluding the pivot subframe is # 1, # 2, # 3, # 4, # 5 and # 6 And can be located at # 8.

In Fig. 15, the pivot subframe is located in subframe # 4, # 5, # 6, and # 7, but this is only an example. Other FDD frames with pivot subframes in different locations can be considered equally.

16 is a diagram illustrating a TDD frame structure having a CP length of 1 / 32Tu and an FDD frame structure having a commonality with the TDD frame structure according to an embodiment of the present invention. 16, the remaining subframes except the SFT-3 type subframe are SFT-1 type subframes.

Referring to FIG. 16, in the first TDD frame structure of the present embodiment, the DL / UL ratio is 4: 4 and the CP length is 1 / 32Tu. The total length of the frame is 5 ms, the DL interval is set to 2450.76 μs including 26 OFDM symbols having a CP length of 1 / 32Tu from the start point of the frame, and a part of the TTG interval idle time of Table 2 from 2450.76 μs The TTG interval is set to 2489.24 μs including the 38.48 μs interval including the 38.48 μs interval, and the UL interval is set to 4940 μs including 26 OFDM symbols having a CP length of 1 / 32Tu from 2489.24 μs. The RTG section is set up to the last point of the frame including the 60-μs section corresponding to the RTG section of Table 2.

Therefore, the DL section is composed of two SFT-3 subframes and two SFT-1 subframes, and the UL section is composed of two SFT-3 subframes and two SFT-1 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the second TDD frame structure of this embodiment, the DL / UL ratio is 5: 3 and the CP length is 1/32 Tu. This structure is the same as the frame structure with the CP length of 1 / 32Tu in Fig. Accordingly, the DL section is composed of two SFT-3 subframes and three SFT-1 subframes, and the UL section is composed of two SFT-3 subframes and one SFT-1 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the third TDD frame structure of this embodiment, the DL / UL ratio is 6: 2 and the CP length is 1 / 32Tu. This structure is the same as the frame structure with the CP length of 1 / 32Tu in Fig. Therefore, the DL section is composed of two SFT-3 subframes and the four SFT-1 subframes, and the UL section is composed of two SFT-3 subframes. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

In the fourth TDD frame structure of this embodiment, the DL / UL ratio is 7: 1 and the CP length is 1 / 32Tu. This structure is the same as the frame structure with the CP length of 1 / 32Tu in Fig. Therefore, the DL section is composed of three SFT-3 subframes and four SFT-1 subframes, and the UL section is composed of one SFT-3 subframe. Here, there is no restriction on the arrangement of the subframe types in the UL section and the DL section.

When a TDD frame is configured as described above, a frame structure having a CP length of 1 / 8Tu and a DL / UL switching section coincide with each other, and even when a system having a CP length of 1 / 8Tu exists in an adjacent cell, Interference between link transmissions can be minimized.

The DL section includes a plurality of SFT-3 type subframes. When the DL / UL ratio is 4: 4, the SFT-3 type subframe may be located in two places among # 1, # 2, # 3, and # 4. If the DL / UL ratio is 5: 3 The SFT-3 type subframe may be located in two places among # 1, # 2, # 3, # 4 and # 5. When the DL / UL ratio is 6: 2, # 1, # 2, # 3, # 4, # 5 and # 6. When the DL / UL ratio is 7: 1, the SFT- , # 3, # 4, # 5, # 6, and # 7.

Also, the UL section includes a plurality of SFT-3 type subframes. When the DL / UL ratio is 4: 4, the SFT-3 type subframe may be located in two places among # 5, # 6, # 7 or # 8. If the DL / UL ratio is 5: 3, 3 type subframe may be located in two places among # 6, # 7, or # 8. When the DL / UL ratio is 6: 2, the SFT-3 type subframe is located in # 7 and # 8 If the DL / UL ratio is 7: 1, the SFT-3 type subframe may be located at # 8.

However, if the TTG interval requires a longer interval than 38.48 μs, two OFDM symbols can be allocated in the TTG interval. For example, one of the OFDM symbols in the UL section may be further allocated for the TTG section, and the TTG section may be set to 132.74 占 퐏. Here, when the DL / UL ratio is 4: 4, the SFT-3 type subframe has two digits of # 1, # 2, # 3 and # 4 and one of # 5, # 6, # 7 and # 8 Subframes in the form of SFT-3 may have two digits # 1, # 2, # 3, # 4 and # 5 and # 6, # 7 and # # 8, and if the DL / UL ratio is 6: 2, the subframe of the SFT-3 type is allocated to one of # 1, # 2, # 3, # 4, # 5 and # 6 Position and # 7 and # 8. When the DL / UL ratio is 7: 1, the subframe of the SFT-3 type can be located in two places among # 1, # 2, # 3, # 4, # 5, # 6 and # 7, .

Next, referring to the FDD frame structure, the FDD frame includes one pivot subframe. As shown in FIG. 16, the pivot subframe may be a SFT-3 type subframe. Also, the pivot subframe may be located at a position corresponding to the TTG section of the TDD frame. That is, when the DL / UL ratio is 4: 4, since the TTG section in the TDD frame is located between # 4 and # 5, the pivot subframe in the FDD frame can be located at # 4 or # 5. Also, when the DL / UL ratio is 5: 3, the TTG section in the TDD frame is located between # 5 and # 6, so that the pivot subframe in the FDD frame can be located at # 5 or # 6. Also, when the DL / UL ratio is 6: 2, since the TTG section in the TDD frame is located between # 6 and # 7, the pivot subframe in the FDD frame can be located at # 6 or # 7. However, since the UL section includes two SFT-3 type subframes, the position of the pivot subframe is preferably # 6. Also, when the DL / UL ratio is 7: 1, the TTG section in the TDD frame is located between # 7 and # 8, so that the pivot subframe in the FDD frame can be located at # 7 or # 8. However, since the UL section includes one SFT-3 type subframe, the position of the pivot subframe is preferably # 7.

 In order to maintain commonality with the TDD frame, two SFT-3 type subframes are positioned before the pivot subframe, and two SFT-3 type subframes are positioned behind the pivot subframe. That is, when the DL / UL ratio is 4: 4, the SFT-3 type subframe except for the pivot subframe has two digits of # 1, # 2, and # 3 and # # 2, # 3, and # 4, and # 6 and # 7, if the pivot subframe is located at # 5, # 6, # 7, And # 8. If the DL / UL ratio is 5: 3, the subframe of the SFT-3 type excluding the pivot subframe is # 1 and # 2 when the pivot subframe is located at # 5. # 2, # 3, and # 4 when the pivot subframe is located at # 2, # 3, and # 4 and # 2, # 7, # 5 and # 7 and # 8, and if the DL / UL ratio is 6: 2, the subframe of the SFT-3 type except for the pivot subframe is located in the pivot subframe # 6 In case # 1, # 2, # 3, # 4 and # 5 And # 8 are located at # 7 and # 8, or when the pivot subframe is located at # 7, the three digits of # 1, # 2, # 3, # 4, # 5, The subframes of the SFT-3 type except for the pivot subframe are # 1, # 2, # 3, # 4, and # 4 when the pivot subframe is located at # 7, when the DL / UL ratio is 7: Four of # 1, # 2, # 3, # 4, # 5, # 6, and # 7 are located at # 8 in # 5 and # 6 and at # 8 if the pivot subframe is located at # Can be located.

In Figure 16, the pivot subframe is located in subframe # 4, # 5, # 6, and # 7, but this is only an example. Other FDD frames with pivot subframes in different locations can be considered equally.

As shown in FIGS. 13 to 16, when a TDD frame structure is constructed, mutual interference does not occur even when a frame structure having different CP length coexists in adjacent cells. That is, the UL interval of a frame having a CP length of 1 / 8Tu and the UL interval of a frame having a CP length of 1 / 4Tu, 1 / 16Tu or 1 / 32Tu, The DL sections of a frame having a CP length of 1/4 Tu, 1/16 Tu or 1 / 32Tu are not overlapped, and mutual interference does not occur.

13 to 16, since the FDD frame structure has a commonality with the TDD frame, it is possible to reuse related communication algorithms such as an algorithm used in the TDD system or a resource allocation method in the FDD system have.

The following Table 4 summarizes the features of FIGS. 13 to 16 and shows the characteristics of the TDD frame structure according to an embodiment of the present invention.

Parameters Values or Features DL / UL Ratio with a CP of 1 / 8Tu 5: 3 6: 2 7: 1 4: 4 5: 3 6: 2 7: 1 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 4Tu 1 / 16Tu 1 / 32Tu TDD No.of SFT-1 Subframes 5 6 4 No.of SFT-2 and SFT-3 2 2 4 Positions of SFT-1 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes
Any position that avoids the positions of SFT-2 and SFT-3 Subframes
Positions of SFT-2 Subframes # 5 # 6 # 7 N / A N / A N / A N / A N / A N / A N / A Positions of SFT-3 Subframes One among # 1, # 2, # 3
and # 4 One
among
#One,
#2,
# 3,
#4
and
# 5 One
among
#One,
#2,
# 3,
# 4, # 5
and
# 6 One among # 1, # 2, # 3 and # 4 + One among # 5, # 6, # 7 and # 8
One among among
#One,
#2,
# 3,
#4
and
# 5
+
One among # 6, # 7 and # 8 One among among
#One,
#2,
# 3,
#4,
# 5
and
# 6
+
One among # 7 and # 8 One among among
#One,
#2,
# 3,
# 4, # 5, # 6
and
# 7
+
#8
Two among # 1, # 2, # 3, # 4 and # 5
+
Two among # 6, # 7 and # 8 Two among # 1, # 2, # 3, # 4, # 5 and # 6
+
# 7 and # 8 Two among # 1, # 2, # 3, # 4, # 5, # 6 and # 7
+
#8

The following Table 5 summarizes the features of FIGS. 13 to 16 and shows the characteristics of the TDD frame when the CP length is 1 / 4Tu and the basic subframe is composed of SFT-2 type subframes according to an embodiment of the present invention. .

Parameters Value or Features DL / UL Ratio with a CP of 1/8 4: 4 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 4Tu No.of SFT-1
Subframes 2 No.of SFT-2 and SFT-3 Subframes 6 Positions of SFT-1 Subframes One among # 1, # 2, # 3 and # 4 + One among # 5, # 6, # 7 and # 8 One among # 1, # 2, # 3, # 4 and # 5 + One among # 6, # 7 and # 8 One among # 1, # 2, # 3, # 4, # 5 and # 6 + One among # 7 and # 8 One among # 1, # 2, # 3, # 4, # 5, # 6 and # 7 + # 8 Positions of SFT-2 Subframes EAny position that avoids the positions of SFT-1 and SFT-3 Subframes Positions of SFT-3 Subframes N / A

Table 6 below summarizes the features of FIGS. 13 to 16, and shows the characteristics of a TDD frame when a CP length is 1 / 32Tu and two OFDM symbols are allocated in a TTG interval according to an embodiment of the present invention.

Parameters Values or Features DL / UL Ratio with a CP of 1/8 4: 4 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 32Tu No.of SFT-1
Subframes 5 No.of SFT-2 and SFT-3 Subframes 3 Positions of
SFT-1 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes Positions of
SFT-2 Subframes N / A Positions of SFT-3 Subframes Two among # 1, # 2, # 3 and # 4 + One among # 5, # 6, # 7 and # 8 Two among # 1, # 2, # 3, # 4 and # 5 + One among # 6, # 7 and # 8 Two among # 1, # 2, # 3, # 4, # 5 and # 6 + One among # 7 and # 8 Two among # 1, # 2, # 3, # 4, # 5, # 6 and # 7 + # 8

Table 7 below summarizes the features of FIGS. 13 to 16 and is a table summarizing the features of the FDD frame structure according to an embodiment of the present invention.

Parameters Values or Features DL / UL Ratio with a CP of 1 / 8Tu 5: 3 6: 2 7: 1 4: 4 5: 3 6: 2 7: 1 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 4Tu
1 / 16Tu 1 / 32Tu FDD No.of SFT-1 Subframes 6 5 3 No.of SFT-2 and SFT-3 One 3 4 Type of Pivot Subframes SFT-1 SFT-3 SFT-3 Positions of Pivot Subframe (Option 1) # 5 # 6 # 7 #4 # 5 # 6 # 7
# 5 # 6 # 7 Positions of Pivot Subframe (Option 2) # 5 # 6 # 7 # 6 Positions of SFT-1 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes Except the positions of SFT-2 and SFT-3 Subframes Except the positions of SFT-2 and SFT-3 Subframes Positions of SFT-2 Subframes N / A N / A N / A N / A N / A N / A N / A N / A N / A N / A Positions of SFT-3 Subframes for Option 1 One among # 1, # 2, # 3 and # 4 One among # 1, # 2, # 3, # 4 and # 5 One among # 1, # 2, # 3, # 4, # 5 and # 6 One among # 1, # 2 and # 3 + One among # 5, # 6, # 7 and # 8 One among # 1, # 2, # 3, and # 4 + One among # 6, # 7 and # 8 One among # 1, # 2, # 3, # 4 and # 5 + One among # 7 and # 8 One among # 1, # 2, # 3, # 4, # 5 and # 6 + # 8 Two among # 1, # 2, # 3 and # 4 + Two among # 6, # 7 and # 8 Two among # 1, # 2, # 3, # 4 and # 5 +
# 7 and # 8 Three among # 1, # 2, # 3, # 4, # 5 and # 6 + # 8 Positions of SFT-3 Subframes for Option 2 Same as Option 1 Same as Option 1 Same as Option 1 One among # 1, # 2, # 3 and # 4 + One among # 6, # 7 and # 8 One among # 1, # 2, # 3, # 4 and # 5 + One among # 7 and # 8 One among # 1, # 2, # 3, # 4, # 5 and # 6 + # 8 Same as Option 1 Two among # 1, # 2, # 3, # 4 and # 5 +
# 7 and # 8 Same as Option 1 Same as Option 1

The following Table 8 summarizes the additional features of FIGS. 13 to 16, and shows the FDD frame when the CP length is 1/4 Tu and the basic subframe is composed of SFT-2 type subframes according to an embodiment of the present invention. .

Parameters Values or Features DL / UL Ratio with a CP of 1/8 Tu 4: 4 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 4Tu No.of SFT-1 Subframes 3 No.of SFT-2 and SFT-3 Subframes 5 Type of Pivot Subframe SFT-1 Positions of Pivot Subframes (Option 1) #4 # 5 # 6 # 7 Positions of Pivot Subframes (Option 2) # 5 # 6 # 7 Positions of SFT-1 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes Positions of SFT-2 Subframes (Option 1) Two among # 1, # 2 and # 3 + Three among # 5, # 6, # 7 and # 8 Three among # 1, # 2, # 3 and # 4 + Two among # 6, # 7 and # 8 Four among # 1, # 2, # 3, # 4 amd # 5 + One among # 7 and # 8 Five among # 1, # 2, # 3, # 4, # 5 and # 6 Positions of SFT-2 Subframes (Option 2) Three among # 1, # 2, # 3 and # 4 + Two among # 6, # 7 and # 8 Four among # 1, # 2, # 3, # 4 and # 5 + One among # 7 and # 8 Five among # 1, # 2, # 3, # 4, # 5 and # 6 Positions of SFT-3 Subframes N / A N / A
N / A
N / A

The following Table 9 summarizes the additional features of FIGS. 13 to 16, and summarizes the characteristics of the FDD frame when the CP length is 1 / 32Tu and two OFDM symbols are allocated in the TTG interval according to an embodiment of the present invention Table.

Parameters Values or Features DL / UL Ratio with a CP of 1/8 Tu 4: 4 5: 3 6: 2 7: 1 CP lengths (μs) 1 / 32Tu No.of SFT-1 Subframes 4 No.of SFT-2 and SFT-3 Subframes 4 Type of Pivot Subframe SFT-3 Positions of Pivot Subframes (Option 1) # 5 # 6 # 7 #8
Positions of Pivot Subframes (Option 2) Positions of SFT-1 Subframes Any position that avoids the positions of SFT-2 and SFT-3 Subframes Positions of SFT-2 Subframes N / A Positions of SFT-3 Subframes (Option 1) Two among # 1, # 2, # 3 and # 4 + One among # 6, # 7 and # 8 Two among # 1, # 2, # 3, # 4 and # 5 + One among # 7 and # 8 Two among # 1, # 2, # 3, # 4, # 5 and # 6 + # 8 Three among # 1, # 2, # 3, # 4, # 5, # 6 and # 7 Positions of SFT-3 Subframes (Option 2) Same as Option 1 Same as Option 1 Same as Option 1 Same as Option 1

17 is a block diagram showing a radio communication apparatus used in the above-described embodiment. The wireless device 50 may be part of a terminal. The wireless device 50 includes a processor 51, a memory 52, an RF unit 53, a display unit 54, and a user interface unit 55. The processor 51 sets at least one subframe in the frame. The frame can be configured in the manner described above. The memory 52 is connected to the processor 51 and stores various information for setting the subframe in the frame. The display unit 54 displays various information of the terminal and can use well known elements such as a liquid crystal display (LCD) and an organic light emitting diode (OLED). The user interface unit 55 may be a combination of a well-known user interface such as a keypad or a touch screen. The RF unit 53 is connected to the processor and transmits and / or receives subframes within the frame.

According to the present invention, when frame structures having various CP lengths supporting the IEEE 802.16m format coexist in adjacent cells, mutual interference during data transmission can be mitigated.

In addition, an FDD frame structure having commonality with the TDD frame can be provided, and related communication algorithms such as an algorithm used in the TDD system and a resource allocation method can be reused in the FDD system.

The present invention may be implemented in hardware, software, or a combination thereof. (DSP), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, a microprocessor, and the like, which are designed to perform the above- , Other electronic units, or a combination thereof. In software implementation, it may be implemented as a module that performs the above-described functions. The software may be stored in a memory unit and executed by a processor. The memory unit or processor may employ various means well known to those skilled in the art.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. It will be understood that various modifications and changes may be made without departing from the spirit and scope of the invention. Accordingly, modifications of the embodiments of the present invention will not depart from the scope of the present invention.

Claims (15)

A method for a terminal to communicate with a base station,
Transmitting and receiving signals to and from the base station based on a base station and a frame,
The frame includes a plurality of first sub-frames, each of which includes seven orthogonal frequency division multiple access (OFDMA) symbols, and a plurality of second sub-frames, each of which includes six OFDMA symbols,
Wherein the frame is a time division duplexing (TDD) frame,
Wherein the frame comprises two first type subframes and six second type subframes,
The fourth type second subframe among the six second type subframes includes idle symbols,
And at least five of the six second type subframes are disposed between the two first type subframes. The method of claim 1, wherein the two first type subframes and the six second type subframes are divided into a plurality of uplink subframes and a plurality of downlink subframes. The method of claim 2, wherein the ratio of the plurality of uplink subframes to the plurality of downlink subframes is one of 4: 4, 6: 2, 7: 1, and 5: 3. . 2. The method of claim 1, wherein the frame has a cyclic prefix (CP) length of 1/16 Tu (useful symbol time). A terminal communicating with a base station,
A display unit;
A transceiver; And
And a processor connected to the display unit and the transceiver for transmitting and receiving signals to and from the base station based on the base station and the frame,
The frame includes a plurality of first sub-frames, each of which includes seven orthogonal frequency division multiple access (OFDMA) symbols, and a plurality of second sub-frames, each of which includes six OFDMA symbols,
Wherein the frame is a time division duplexing (TDD) frame,
Wherein the frame comprises two first type subframes and six second type subframes,
The fourth type second subframe among the six second type subframes includes idle symbols,
And at least five of the six second type subframes are arranged between the two first type subframes. 6. The terminal of claim 5, wherein the frame has a cyclic prefix (CP) length of 1/16 Tu (useful symbol time). delete delete delete delete delete delete delete delete delete

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