KR101635885B1 - Method for transmitting signal in wireless communication system - Google Patents

Abstract

A method of signal transmission in a wireless communication system is disclosed. The UE can transmit / receive a signal using a frame structure having a CP length corresponding to 1/4 of the effective symbol length. In addition, a frame structure having a CP length corresponding to 1/4 of an effective symbol length designed to coexist with a frame structure having a different CP length can be used to transmit and receive a signal without causing collision and interference.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for transmitting a signal in a wireless communication system,

The present invention relates to a signal transmission method, and more particularly, to a method for transmitting a signal using a predetermined frame structure in a wireless communication system.

The IEEE 802.16m system can support both a Frequency Division Duplex (FDD) scheme and a Time Division Duplex (TDD) scheme including an operation of an H-FDD (Half-Frequency Division Duplex) terminal. The IEEE 802.16m system uses Orthogonal Frequency Division Multiplexing Access (OFDMA) as a multiple access method in a downlink and an uplink. The contents of the OFDMA parameters are shown in Table 1 below.

Hereinafter, a frame structure of the IEEE 802.16m system will be briefly described.

1 is a diagram showing a basic frame structure in an IEEE 802.16m system.

Referring to FIG. 1, each 20 ms superframe is divided into four equal-sized 5 ms radio frames, and the superframe starts with a superframe header (SFH). When using the same OFDMA parameters as shown in Table 1 with either channel bandwidth of 5 MHz, 10 MHz or 20 MHz, each 5 ms radio frame is composed of 8 subframes. One subframe may be allocated for downlink or uplink transmission. The first type is a subframe composed of six OFDMA symbols, the second type subframe is a subframe consisting of seven OFDMA symbols, and the third type subframe is a subframe composed of six OFDMA symbols.

The basic frame structure can be applied to both the FDD method and the TDD method including the operation of the H-FDD terminal. In the TDD system, the number of switching points in each radio frame is two. The switching points may be defined according to the change of direction from the downlink to the uplink or from the uplink to the downlink.

The H-FDD terminal can be included in the FDD system, and the frame structure in terms of the H-FDD terminal is similar to the TDD frame structure. However, the downlink and uplink transmissions occur in two separate frequency bands. The transmission gaps between the downlink and the uplink (and vice versa) are required to switch the transmit and receive circuits.

2 is a diagram illustrating an example of a TDD frame having a downlink and uplink ratio of 5: 3.

Referring to FIG. 2, assuming that the OFDMA symbol period has a symbol duration of 102.857 μs and a length corresponding to 1/8 of an effective symbol length (Tu) as a CP (Cyclic Prefix) length, The lengths of the 3 type sub-frames are 0.617 ms and 0.514 ms, respectively. And the last downlink subframe SF4 is a third type subframe. The Transition Transition Gaps (TTG) and the Receive Transition Gaps (RTG) are 105.714 μs and 60 μs, respectively. In other numerology, the number of subframes per frame and the number of symbols in a subframe may be different.

3 is a diagram showing an example of a frame structure in the FDD scheme.

Referring to FIG. 3, a base station supporting the FDD scheme can simultaneously support half-duplex and full-duplex terminals operating on the same RF carrier. A terminal supporting the FDD scheme should use either the H-FDD scheme or the FDD scheme. All subframes are available for transmission in both the downlink and the uplink. The downlink and uplink transmissions may be separated in the frequency domain. One superframe is divided into four frames, and one frame consists of eight subframes.

4 is a diagram illustrating a TDD and FDD frame structure having a CP length corresponding to 1/16 of an effective symbol length Tu.

Referring to FIG. 4, for a channel bandwidth of 5 MHz, 10 MHz, and 20 MHz, a frame of an IEEE 802.16m system having a CP length corresponding to 1/16 of an effective symbol length Tu is divided into five first type sub- Frame and three second subframes, and has six first type subframes and two second type subframes in the TDD scheme.

Assuming that the OFDMA symbol duration is 97.143 mu s and the CP length is 1/16 of the effective symbol length Tu, the lengths of the first type subframe and the second type subframe are 0.583 ms and 0.680 ms. TTG and RTG are 82.853 μs and 60 μs, respectively. In other numerology, the number of subframes per frame and the number of symbols in a subframe may be different.

As described above, the IEEE 802.16m system defines only the OFDMA parameters and the frame structure for the case where the CP length is 1/8 Tb and 1/16 Tb for the 5 MHz, 10 MHz, and 20 MHz channel bandwidths. That is, the frame structure for the CP length of 1/4 Tb has not been proposed so far.

Also, in the case of a frame structure having a CP length of 1/4 Tb, a frame structure having a CP length of 1/8 Tb or 1/16 Tb and a problem in which interference occurs at switching points between downlink and uplink There is a problem that can occur. However, there has been no proposal for a new frame structure capable of solving these problems and mutual coexistence.

SUMMARY OF THE INVENTION The present invention provides a signal transmission method in a wireless communication system.

The technical problems to be solved by the present invention are not limited to the technical problems and other technical problems which are not mentioned can be understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a signal transmission method including: receiving a signal from a base station using a predetermined frame structure; And transmitting a signal to the base station using the predetermined frame structure. In the predetermined frame structure, one frame is composed of 7 subframes, and each subframe is divided into 6 OFDMA (Orthogonal Frequency Division A first type subframe consisting of multiple access symbols or a second type subframe consisting of seven OFDMA symbols.

The predetermined frame may be a Time Division Duplex (TDD) frame or a Frequency Division Duplex (FDD) frame.

In addition, each subframe in the TTD frame includes only the first type subframe.

In addition, the TDD frame includes a downlink interval and an uplink interval following the downlink interval, and a transmission transition gap (TTG) is located between the downlink interval and the uplink interval, It is preferable that RTG (Receive Transition Gaps) be located after the last subframe of the uplink interval.

Preferably, the ratio of the number of downlink subframes to the number of uplink subframes in the TTD frame is any one of 2: 5, 3: 4, 4: 3, 5: 2, and 6: 1.

The FDD frame includes six first type subframes and one second type subframe.

The second type subframe in the FDD frame may be located in the same order as the last subframe of the downlink subframe among the subframes in the TDD frame.

The second type subframe in the FDD frame may be located in the fourth subframe.

An idle time is preferably located after the last subframe in the FDD frame.

The CP length of the predetermined frame may be 1/4 of the effective symbol length, and the predetermined frame structure may have a channel bandwidth of any one of 5 MHz, 10 MHz, and 20 MHz.

According to another aspect of the present invention, there is provided a signal transmission method including: receiving a signal from a base station using a predetermined frame structure; And transmitting a signal to the base station using the predetermined frame structure. In the predetermined frame structure, one frame is composed of 8 subframes, and each subframe is divided into six OFDMA (Orthogonal Frequency Division Multiple Access) symbol or a third type subframe consisting of five OFDMA symbols.

According to the present invention, it is possible to transmit and receive a signal using a TDD frame structure having a CP length corresponding to a quarter of the effective symbol length and an FDD frame structure having a commonality with the TDD frame structure.

According to the present invention, signals can be transmitted and received using a TDD frame structure having a different CP length and a TDD frame structure capable of mutually coexisting.

The effects obtained by the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those skilled in the art from the following description will be.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
1 is a diagram showing a basic frame structure in an IEEE 802.16m system,
2 is a diagram illustrating an example of a TDD frame having a downlink and uplink ratio of 5: 3,
3 is a diagram showing an example of a frame structure in the FDD scheme,
4 is a diagram showing a TDD and FDD frame structure having a CP length corresponding to 1/16 of an effective symbol length (T _u )
5 is a diagram illustrating an example of a symbol structure including a CP (cyclic prefix)
6 is a diagram illustrating an example of a TDD frame structure having a CP length of 1/4 Tb in a 5 MHz, 10 MHz, or 20 MHz band,
7 to 11 illustrate an example of a TDD frame structure having a CP length of 1/4 Tb that can coexist with a frame structure having a different CP length according to the number of downlink subframes and the number of uplink subframes, One drawing,
12 shows an example of a TDD frame structure having a CP length of 1/4 Tb,
13 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb,
14 to 17 illustrate an example of a TDD frame structure having a CP length of 1/4 Tb that can coexist with a frame structure having a different CP length according to the number of downlink subframes and the number of uplink subframes, respectively One drawing,
18 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb,
19 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb,
20 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb,
21 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb,
22 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb,
23 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb,
24 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb,
25 is a view showing an example of a TDD frame structure having a CP length of 1/4 Tb,
26 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The detailed description set forth below in conjunction with the appended drawings is intended to illustrate exemplary embodiments of the invention and is not intended to represent the only embodiments in which the invention may be practiced. The following detailed description includes specific details for a better understanding of the present invention. However, those skilled in the art will appreciate that the present invention may be practiced without these specific details. For example, in the following description, certain terms are mainly described, but they need not be limited to these terms, and they may have the same meaning when they are referred to as arbitrary terms. Further, the same or similar elements throughout the present specification will be described using the same reference numerals.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

The techniques described below may be used in various communication systems, which may provide various communication services such as voice, packet data, and so on. The technology of the communication system can be used for a downlink or an uplink. The base station may be replaced by terms such as a fixed station, a base station, a Node B, an eNode B (eNB), an access point, an ABS, and the like. In addition, a mobile station (MS) can be replaced with terms such as a UE (User Equipment), a Subscriber Station (SS), a Mobile Subscriber Station (MSS), an AMS or a Mobile Terminal.

Also, the transmitting end refers to a node that transmits data or voice service, and the receiving end refers to a node that receives data or voice service. Therefore, in the uplink, the terminal may be the transmitting end and the base station may be the receiving end. Similarly, in the downlink, the terminal may be the receiving end and the base station may be the transmitting end.

The terminal of the present invention may be a PDA (Personal Digital Assistant), a cellular phone, a PCS (Personal Communication Service) phone, a GSM (Global System for Mobile) phone, a WCDMA (Wideband CDMA) Can be used.

Embodiments of the present invention may be implemented in accordance with standard documents disclosed in at least one of the Institute of Electrical and Electronics Engineers (IEEE) 802 systems, 3GPP systems, 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) systems and 3GPP2 systems It can be backed up. That is, the steps or portions of the embodiments of the present invention that are not described in order to clearly illustrate the technical idea of the present invention can be supported by the documents. In addition, all terms disclosed in this document may be described by the standard document. In particular, embodiments of the present invention may be supported by documents such as P802.16-2004, P802.16e-2005 and P802.16Rev2, which are standard documents of the IEEE 802.16 system.

The specific terminology used in the following description is provided to aid understanding of the present invention, and the use of such specific terminology may be changed into other forms without departing from the technical idea of the present invention.

A basic principle of Orthogonal Frequency Division Multiplexing (OFDM), which is a multicarrier modulation scheme in a wireless communication system, will be described as follows.

 In an OFDM system, a data stream having a high-rate is divided into a large number of data streams having a slow-rate, which is transmitted simultaneously using a plurality of carriers. Each of the plurality of carriers is referred to as a subcarrier. Since orthogonality exists among a plurality of carriers in an OFDM system, even if frequency components of carriers overlap each other, detection at the receiving end is possible. A data stream having a high-speed data rate is converted into a data stream having a plurality of low data rates through a serial-to-parallel (S / P) converter, and a plurality of data streams, And then the data streams may be combined and transmitted to the receiving end.

A plurality of parallel data streams generated by the serial-to-parallel conversion unit can be transmitted on a plurality of subcarriers by inverse discrete Fourier transform (IDFT). At this time, the IDFT can be efficiently implemented using Inverse Fast Fourier Transform (IFFT). Since the symbol duration of a sub-carrier having a low data rate is increased, the relative signal dispersion in time caused by multipath delay spreading is reduced.

In wireless communication using the OFDM scheme, a guard interval longer than a delay spread of a channel between symbols may be inserted to reduce inter-symbol interference. That is, while each symbol is transmitted through the multipath channel, a guard interval longer than the maximum delay spread of the channel is inserted between consecutive symbols. At this time, in order to prevent the orthogonality destruction between the subcarriers, the signal of the last interval (i.e., guard interval) of the valid symbol interval is copied and inserted in the front part of the symbol. This is referred to as a cyclic prefix (CP).

5 is a diagram illustrating an example of a symbol structure including a CP (cyclic prefix).

Referring to FIG. 5, the symbol period Ts is the sum of the effective symbol period Tb and the guard period Tg at which the actual data is transmitted. At the receiving end, demodulation is performed by taking the data during the effective symbol interval after removing the guard interval. The transmitting end and the receiving end can be synchronized with each other using the cyclic prefix, and orthogonality between the data symbols can be maintained. The symbol referred to in the present invention may be an OFDMA symbol.

A frame structure in an 802.16m system having a CP length (hereinafter, referred to as a CP length of 1/4 Tb) corresponding to 1/4 of an effective symbol length in a channel bandwidth of 5 MHz, 10 MHz, and 20 MHz TDD frame and FDD frame) will be described. In addition, a TDD frame structure having a CP length of 1/8 Tb or a CP length of 1/16 Tb with respect to the same channel bandwidth of 5 MHz, 10 MHz, and 20 MHz and a TDD frame structure capable of mutually coexisting will be described. The FDD frame structure having many similarities with the TDD frame structure proposed in the present invention will also be described.

There are four types of subframes in the IEEE 802.16m system. The first type is a subframe consisting of six OFDMA symbols, the second type subframe is a subframe consisting of seven OFDMA symbols, the third type subframe is a subframe consisting of six OFDMA symbols, the fourth type subframe is It can be defined as a subframe consisting of nine OFDMA symbols. At this time, the fourth type subframe can be used in a frame structure in a channel bandwidth of 8.75 MHz.

As shown in Table 1, in the case of a frame structure having a CP length of 1/4 Tb in the 5 MHz, 10 MHz, or 20 MHz bands, the number of OFDMA symbols usable is 43. Therefore, for a basic frame structure in the 5 MHz, 10 MHz, or 20 MHz band, a frame structure having a CP length of 1/4 Tb is formed using each subframe type defined according to the number of symbols constituting one subframe .

6 is a diagram illustrating an example of a TDD frame structure having a CP length of 1/4 Tb in 5 MHz, 10 MHz, and 20 MHz channel bandwidths.

Referring to FIG. 6, one frame has 8 subframes and 43 symbols can be used. In this case, a case where 43 symbols are used for the first type sub-frame and the third type sub-frame can be considered. In the TDD frame, one symbol may be allocated as an idle period of the TTG / RTG. The remaining 42 symbols may be allocated to two first type subframes and six third type subframes. Considering up to one symbol used as the idle period for TTG and RTG, the number of first type subframes used for constructing a frame is three, so there is no need to define additional subframes to construct a frame.

That is, in the case of the TDD frame, six symbols can be allocated to the last subframe of the downlink, where one symbol is allocated for the TTG and RTG periods, so that the last subframe of the downlink may be a third type subframe. Also, by making the number of subframes per frame equal to the frame structure having another CP length (for example, a CP length of 1/8 Tb or a CP length of 1/16 Tb), H -AQ (Hybrid-Automatic Repeat reQuest) protocol or control information of each subframe unit in the same form.

In FIG. 6, the first type subframe, which exists in the downlink and the uplink, may be located at any position within the downlink and uplink regions. As an example, the first type subframe may be located in the first subframe and the last subframe in the frame.

6, the ratio of the number of downlink subframes and the number of uplink subframes available for the TDD scheme in one frame composed of eight subframes is (2: 6), (3: 5), (4: 4), (5: 3), (6: 2), and (7: 1). (4: 4), (5: 3), (6: 2), and (7: 1), the ratio of the number of downlink subframes to the number of uplink subframes is ), The ratio of the total number of symbols allocated to the corresponding downlink subframes to the total number of symbols allocated to the uplink subframes is (11:31), (16:26), (21:21) , (26:16), (31:11), (36: 6). Here, since the superframe header (SFH) is composed of six OFDMA symbols, the first subframe of the downlink preferably has a first type subframe structure. In this case, in order to design a frame structure in which no interference occurs at the switching points between the downlink and uplink in the case of the six downlink subframe number and uplink subframe ratio ratios, 5xk + 1 (Where k is the number of downlink subframes) and 5x j + 1 (where j is the number of uplink subframes) in the uplink.

FIGS. 7 to 11 illustrate a TDD frame structure having a CP length of 1/4 Tb, which can coexist with a TDD frame structure having a different CP length, according to an example of the number of downlink subframes and the number of uplink subframes, respectively Fig.

7 to 11, the ratio of the number of downlink subframes to the number of uplink subframes is 3: 5, 4: 4, 5: 3, 6: 2, 7 : 1). At this time, when the ratio of the number of downlink subframes to the number of uplink subframes is (3: 5), (4: 4), (5: 3), (6: 2) The ratio of the total number of symbols allocated to the DL subframes to the total number of symbols allocated to the UL subframes is (16:26), (21:21), (26:16), (31:11) , (36: 6). Here, in the last subframe located in a section for switching from the downlink to the uplink, a subframe including six symbols including an idle period may be located. However, in order to make a delay required for a TTG in a TDD frame structure, The third type subframe consisting of five symbols can be located. In this manner, in the TDD frame, one symbol can be allocated as an idle period of the TTG / RTG. This configuration can be applied regardless of the ratio of the number of downlink subframes to the number of uplink subframes. That is, for each of the ratios shown in FIGS. 7 to 11.

As shown in FIGS. 7 to 11, if the first type subframe is located in the downlink and the uplink, respectively, interference problems that may occur in a period of switching from the downlink to the uplink can be solved.

In addition, in the frame structure having a CP length of 1/4 Tb, a third type subframe is allocated to the last subframe of the downlink, thereby providing a frame structure having a CP length of 1/8 Tb, a CP length of 1/16 Tb And can coexist with each other.

12 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 12, unlike the first type subframe in the last subframe of the uplink in FIG. 6, in FIG. 12, the structure in which the last subframe of the uplink is shifted to the downlink, It is possible to design a frame structure that can be used by positioning a type sub-frame. At this time, two first type subframes in the downlink area can be located at arbitrary positions. At this time, two first type subframes can be located in the first subframe and the second subframe in the downlink region. Also, in order to utilize a previously defined super frame header (SFH), it may be preferable to place at least one first type subframe at the first position of the frame.

If the ratio of the number of downlink subframes to the number of uplink subframes is (2: 6), the first type subframe may be located at the point of switching from the downlink to the uplink, The third type subframe may be located at the transition point in the case of (4: 4), (5: 3), (6: 2) and (7: 1)

In FIG. 12, two first type subframes located in the downlink may be located at arbitrary positions in the downlink region. For example, as described above, the first type subframe may be arranged in the first subframe and the second subframe in the downlink subframe. At this time, OFDMA symbols of 5 × k + 2 (where K is the number of downlink subframes) and 5 × j (where j is the number of uplink subframes) are allocated to the downlink region and the uplink region, respectively . In this TDD frame, one symbol may be allocated to an idle period of the TTG / RTG.

13 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 13, first type subframes existing in the downlink and uplink regions may be located in the first subframe in which each region starts in the downlink and uplink regions, respectively. That is, the subframes of the downlink and uplink areas may start with the first type subframe. Accordingly, the start point of the downlink and uplink areas can be grasped by using the position of the first type sub frame. In the TDD frame structure shown in FIG. 13, the ratio of the number of downlink subframes to the number of uplink subframes is 7: 1, 6: 2, 5: 3, 4: 4, The ratio of the total number of symbols allocated to the corresponding downlink subframes to the total number of symbols allocated to the uplink subframes is (36: 6), (31:11 ) (26:16), (21:21), (16:26), (11:31).

FIGS. 14 to 17 illustrate an example of a TDD frame structure having a CP length of 1/4 Tb that can coexist with a frame structure having a different CP length according to the number of downlink subframes and the number of uplink subframes, respectively to be.

Referring to FIGS. 14 to 17, the TDD frame structure includes a third type of 5 symbols in the last subframe of the downlink frame for a period of switching from downlink to uplink, like the frame structure shown in FIG. 13 The subframe can be located. This configuration can be applied regardless of the ratio of the number of downlink subframes to the number of uplink subframes. At this time, the number of symbols allocated to the downlink region is 6 + 5xk (k is the number of the allocated third type subframe among the downlink subframes), and the number of symbols allocated to the uplink region is 6 + 5 x n (where n denotes the number of allocated third type subframes in the uplink subframe).

The TDD frame structure shown in FIGS. 14 to 17 is configured such that the number of downlink subframes and the number of uplink subframe numbers are 3: 5 and 4: 4, respectively, as in the TDD frame structure shown in FIGS. , (5: 3), (6: 2), and (7: 1). The TDD frame structure having a CP length of 1/4 Tb may be composed of six symbols including the idle period, but the last subframe located in the downlink-to-uplink section is generally required to have a TTG in the TDD frame structure. A third type subframe of five symbols may be located in the last subframe because one symbol is left in the idle period to make the delay. In this TDD frame, one symbol may be allocated as an idle period of the TTG / RTG. This can be applied regardless of the number of downlink subframes and the number of uplink subframes.

If the first type subframe is located in the downlink and the uplink, respectively, the interference problem in the downlink to uplink switching period can be solved. Therefore, the TDD frame structure having the CP length of 1/4 Tb shown in FIGS. 14 to 17 can be mutually coexistent with the conventional TDD frame structure having the CP length of 1/8 Tb and the CP length of 1/16 Tb have.

18 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

The FDD frame structure shown in FIG. 18 is a frame structure corresponding to the TDD frame structure shown in FIG. 6 to FIG. 43 symbols may be allocated to the FDD frame. The FDD frame may be composed of 8 subframes. In this FDD frame structure, two first type subframes may be included. In the case of the FDD frame structure, unlike the TDD frame structure, there is no section used as the TTG / RTG. Therefore, one additional symbol can be further allocated to the TDD frame structure. There are many ways to use one symbol at a time.

In FIG. 18, as a first case (FDD case 1), one symbol can be added to a third type subframe in a frame to construct a first type subframe and use it. Considering the H-FDD frame structure and the case of dividing into two groups, the generated idle interval symbol is likely to be located in the middle of the frame, so that a further symbol is further allocated to the fourth sub-frame . This is merely an example of an FDD frame structure having a CP length of 1/4 Tb according to the present invention, and there is no restriction on the position of a subframe formed by adding one symbol in the FDD frame structure.

In the second case (FDD case 2), one symbol can be independently added to the subframe located in the first subframe in the frame, and positioned in front of the frame. Since a symbol unit control information (for example, a preamble, a frame control header (FCH) is additionally required) is added to the front symbol of the frame, the added symbol is used for this information, Can be used.

In the third case (FDD case 3), an additional symbol can be placed independently after the third sub-frame considering the H-FDD or the mid-amble in the frame. The arrangement of one additional symbol after the third, fourth or fifth subframe is merely an example, and there is no limit to the position of an additional symbol.

In the fourth case (FDD case 4), one symbol can be allocated to the end of the frame and used to transmit additional information such as sounding without converting the subframe structure for existing data transmission.

19 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

The FDD frame structure shown in FIG. 19 corresponds to the frame structure corresponding to the TDD frame structure shown in FIG. 12 to FIG. The FDD frame may be assigned 43 symbols. [0064] Using the structure in which the 8 subframes shown in FIG. 12 are composed of the first type subframe and the third type subframe, FDD frame structure.

The FDD frame structure may include two or three first type subframes. In particular, the first type subframe may be located in the first subframe, the second subframe in the frame. Also, as in the first case (FDD case 1), the first type subframe may be located in the fourth subframe. Also, the first type subframe may be located in the first subframe of the frame and the positions of the remaining two first type subframes may be located in the frame without limitation.

20 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

The FDD frame structure shown in FIG. 20 corresponds to a frame structure corresponding to the TDD frame structure in which the first type subframe is located in the first subframe of the downlink and uplink. The FDD frame can be allocated 43 symbols. [0156] The FDD frame structure in which the first type subframe is located in the frame in the same manner as the FDD frame structure shown in FIG. 18 is shown. As a first case (FDD case 1), the first type subframe may be located in the first subframe, the fourth subframe, and the fifth subframe. In the second to fourth cases (FDD cases 2 to 4), the first type subframe may be located in the first subframe and the fifth subframe. The position of this first type sub-frame is merely an example, and may be located in any sub-frame within the frame. In order to use a superframe header composed of six symbols defined previously, it is preferable that one type 1 subframe is arranged in the first subframe in the frame.

Up to now, it has been common to have a common frame structure defined at 5 MHz, 10 MHz, or 20 MHz, and to combine the previously defined CP length of 1/8 Tb or CP frame of 1/16 Tb and interference in the downlink / A TDD frame structure having a CP length of 1/4 Tb at 5/10/20 MHz and a FDD structure having commonality can be mutually coexisted with frames having different CPs defined previously.

21 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 21, as a second case of configuring 8 subframes, 43 OFDMA symbols may be composed of a second type subframe and a third type subframe. In the TDD frame, one symbol can be used for the TTG / RTG interval, and the remaining 42 symbols can be used for data transmission. A symbol can be assigned to the idle period of the TTG / RTG.

At this time, each subframe may be composed of a third type subframe consisting of five symbols, in which two symbols remain. The remaining two symbols may be added to any one of the third type subframes to form a second type subframe.

Therefore, one frame may be composed of seven third type subframes and one second type subframe. At this time, it is preferable that one second type subframe formed in the frame is located in the first subframe of the frame in consideration of symbol unit control information (for example, preamble, FCH) transmitted before the frame.

21, the ratio of the number of downlink subframes available in the TDD frame structure to the number of uplink subframes is (2: 6), (3: 5), (4: 4), ), (6: 2), and (7: 1). Here, the number of OFDMA symbols allocated to the downlink may be expressed as 5xk + 2 (where k is the number of downlink subframes), and the number of OFDMA symbols allocated to the uplink is 5xj (where j Is the number of uplink subframes). And a third type subframe may be located at a switching point from the downlink to the uplink.

As described above, FIG. 21 shows a TDD frame structure according to the ratio of the number of downlink subframes to the number of uplink subframes. The second type subframe shown here may be located in the first subframe in the TDD frame . However, this is only an example, and there is no limitation on the position of the second type sub frame in the downlink area. Also, the second type subframe can be used as a switching point between the downlink and the uplink. Therefore, the position of the second type sub-frame is not limited within the frame.

22 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

The FDD frame structure shown in FIG. 22 is a frame structure corresponding to the TDD frame structure shown in FIG. At this time, 43 symbols may be allocated to the FDD frame. The FDD frame structure may be composed of 8 subframes, and may be composed of a first type subframe, a second type subframe, and a third type subframe. In the case of the FDD frame structure, unlike the TDD frame structure, since there is no TTG / RTG section, one additional symbol can be further allocated. There are several ways to use one symbol at a time.

As a first case (FDD case 1), a case may be considered in which a first type subframe is constituted and used by adding one symbol to one subframe among the third type subframes constituted by five symbols in the frame . Since the H-FDD frame structure in which a symbol is added or the second type sub-frame is divided into two groups, the idle symbol generated in the middle of the frame easily exists in the first sub-frame. May be desirable. This is merely an example of an FDD frame structure having a CP length of 1/4 Tb according to the present invention, and there is no restriction on the position of a subframe formed by adding one symbol in the FDD frame structure. The first type subframe formed by adding one symbol in the FDD frame structure and the second type subframe allocated may be placed at arbitrary positions in the frame.

In the second case (FDD case 2), one symbol is added independently to the first subframe located at the front of the frame and positioned in front of the frame. Since the front symbol of the frame mainly requires additional symbol unit control information (for example, preamble, FCH), it uses the added symbol to transmit this information and uses the second type subframe or the third type subframe Data transmission can be performed.

As a third case (FDD case 3), an additional symbol can be independently allocated to the third subframe, the fourth subframe, or the fifth subframe in consideration of the H-FDD or the midamble in the frame. This position is an example and can be placed at any position since there is no restriction on the position of an additional symbol.

In the fourth case (FDD case 4), one symbol may be placed after the last subframe of the frame, without transforming the subframe structure for existing data transmission, to transmit additional information such as sounding.

In the FDD frame structure shown in FIG. 22, the second type subframe is located in the first subframe of the frame, but this is only an example, and the second type subframe in the frame may be located at an arbitrary position.

23 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 23, as an example of a TTD frame structure having a CP length of 1/4 Tb, one frame may be composed of 7 subframes. The frame structure for the ratio of the number of downlink subframes to the number of uplink subframes is (2: 5), (3: 4), (4: 3), (5: 2) . Here, the TTG may be located after the last subframe of the downlink, and the RTG may be located after the last subframe of the uplink. A symbol can be assigned to the idle period of the TTG / RTG.

In the TDD frame structure, the number of available symbols is 42 except for one symbol for TTG / RTG. Therefore, one frame can be formed using only the first type subframe having 6 OFDMA symbols for 7 subframes. In this manner, the first type subframe structure can be inherited by constructing a frame with only one type of the first type subframe. Also, the number of symbols to be allocated to the downlink is 6 x k (where k is the number of downlink subframes) and the number of symbols allocated to the uplink is 6 x j (where j is the number of uplink subframes) .

24 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

The FDD frame structure shown in FIG. 24 is a frame structure corresponding to the TDD frame structure shown in FIG. At this time, 43 symbols may be allocated to the FDD frame. The FDD frame structure having seven subframes can additionally use one symbol used for the TTG / RTG delay, unlike the TDD frame structure. In Fig. 24, one additional usable symbol is shown for each subframe position that can be located in the FDD frame structure. An additional symbol may be located after the first sub-frame, the third sub-frame, the fourth sub-frame, or the seventh sub-frame. An idle interval may exist after the last subframe of the FDD frame.

FIG. 24 shows an FDD frame structure having seven subframes. At this time, one symbol is added to any one first type subframe in the frame to form a second type subframe. At this time, there is no limitation on the position of the second type sub-frame. That is, one additional symbol can be used in the first subframe, the third subframe, the fourth subframe, or the last subframe in the frame. In particular, the second type subframe in the FDD frame may be located in the same order as the last subframe of the downlink among the subframes in the TDD frame. The position of the additional symbol shown here is only one example, and there is no limitation on the position of the symbol.

25 is a diagram showing an example of a TDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 25, one subframe may consist of a second type subframe consisting of seven OFDMA symbols. Since the number of symbols usable in the TDD frame structure is 42, if one symbol is formed by grouping seven symbols, one frame may be composed of 6 subframes. Therefore, one frame can be configured using a single type of subframe. (2: 4), (3: 3), (4: 2) or (5: 1) days in the number of downlink subframes and the number of uplink subframes in a frame constructed using the second type subframe . A symbol can be assigned to the idle period of the TTG / RTG.

26 is a diagram showing an example of an FDD frame structure having a CP length of 1/4 Tb.

Referring to FIG. 26, the FDD frame structure shown in FIG. 26 is a frame structure corresponding to the TDD frame structure shown in FIG. At this time, 43 symbols may be allocated to the FDD frame. In the FDD frame structure constituting a frame using the second type sub-frame, one symbol used as a TTG / RTG in the TDD frame structure can be additionally used. As an example, unlike the case of FIG. 24, when a symbol is added to any existing second type subframe to form a subframe, an additional type of subframe consisting of 8 OFDMA symbols is created. However, this is beyond the scope of the previously defined subframe type.

Therefore, in such a case, a method of using one symbol independently (or individually) may be considered. When one symbol is added independently, additional symbols can be used to transmit symbol unit control information (e.g., preamble, FCH) in the first subframe in the frame as in each case described in the FDD frame structure. Or may be further disposed in the last sub-frame within the frame and used to transmit additional information such as sounding. Also, it can be placed in the middle of the frame in consideration of the H-FDD and the midamble in the frame.

I.e., between the third subframe and the fourth subframe. The position of the symbol presented here is only an example, and there is no restriction on the position of one symbol in the frame.

The UE can transmit and receive signals using the TDD frame structure having the CP length of 1/4 Tb and the FDD frame structure having the commonality with the TDD frame structure.

The embodiments described above are those in which the elements and features of the present invention are combined in a predetermined form. Each component or feature shall be considered optional unless otherwise expressly stated. Each component or feature may be implemented in a form that is not combined with other components or features. It is also possible to construct embodiments of the present invention by combining some of the elements and / or features. The order of the operations described in the embodiments of the present invention may be changed. Some configurations or features of certain embodiments may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments. It is clear that the claims that are not expressly cited in the claims may be combined to form an embodiment or be included in a new claim by an amendment after the application.

Embodiments in accordance with the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of hardware implementation, an embodiment of the present invention may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs) Field Programmable Gate Arrays), a processor, a controller, a microcontroller, a microprocessor, or the like.

In the case of an implementation by firmware or software, an embodiment of the present invention may be implemented in the form of a module, a procedure, a function, or the like which performs the functions or operations described above. The software code can be stored in a memory unit and driven by the processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various well-known means.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the above description should not be construed in a limiting sense in all respects and should be considered illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the scope of equivalents of the present invention are included in the scope of the present invention.

Claims (24)

A method for transmitting and receiving signals in a wireless communication system,
Transmitting and receiving a signal through a frame structure composed of a frequency division duplex (FDD) frame,
Wherein the FDD frame includes 7 subframes, the 7 subframes being composed of 6 first type subframes and 1 second type subframe,
Wherein the FDD frame includes a cyclic prefix (CP), the length of the CP corresponds to 1/4 of the effective symbol length,
Wherein each of the six first type subframes includes six OFDMA symbols and one second type subframe includes seven OFDMA symbols,
Wherein the channel bandwidth of the FDD frame is one of 5 MHz, 10 MHz, and 20 MHz. The method according to claim 1,
Wherein the one second type subframe corresponds to a fourth subframe in the FDD frame. The method according to claim 1,
Wherein an idle time is located after the last subframe on the time axis in the FDD frame. delete A method for transmitting and receiving signals in a wireless communication system,
A transceiver; And
≪ / RTI >
The processor controls the transceiver to transmit and receive a signal through a frame structure composed of a frequency division duplex (FDD) frame,
Wherein the FDD frame includes 7 subframes, the 7 subframes being composed of 6 first type subframes and 1 second type subframe,
Wherein the FDD frame includes a cyclic prefix (CP), the length of the CP corresponds to 1/4 of the effective symbol length,
Wherein each of the six first type subframes includes six OFDMA symbols and one second type subframe includes seven OFDMA symbols,
Wherein the channel bandwidth of the FDD frame is any one of 5 MHz, 10 MHz, and 20 MHz. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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