Method for configurating basic signal allocation unit and method for transmitting signals using the same

The present invention relates to a method of setting a basic signal allocation unit and a method of transmitting a signal using the set basic signal allocation unit.

There is a basic unit of resource allocation for signal transmission for each communication system. In a conventional IEEE 802.16e system, a slot is defined as a signal transmission unit. Here, a slot is a basic data transmission unit and can also be called a minimum resource block.

The slots in the above IEEE 802.16e system will be described below.

In the OFDMA physical layer of an IEEE 802.16e system, slots are defined in both the time domain (eg, the number of OFDMA symbols) and the frequency domain (eg, the number of subcarriers) and constitute a data allocation unit. In this case, the OFDMA slot definition follows the OFDMA symbolic structure. The OFDMA symbol structure is for uplink (hereinafter referred to as UL) or downlink (hereinafter referred to as DL), and for FUSC (Full Usage of SubChannels) or PUSC (Partial Usage of SubChannels). Or different for distributed subcarrier permutation or adjacent subcarrier permutation.

For example, for DL FUSC and DL selective FUSC using distributed subcarrier permutation, one slot can be defined as one subchannel * 1 OFDMA symbol.

Also, for DL PUSC using distributed subcarrier permutation, one slot can be defined as one subchannel * 2 OFDMA symbol.

Also, for UL PUSC and DL TUSC (Tile Usage Of SubChannels) 1 and TUSC2 that use distributed subcarrier permutation, one slot can be defined as one subchannel * 2,3 or 6 OFDMA symbol.

FIG. 1 is a diagram showing a two-dimensional resource allocation concept in OFDMA of an existing IEEE 802.16e system.

As shown in FIG. 1, in the OFDMA of the existing IEEE 802.16e system, the data area is a two-dimensional area composed of a group 101 of adjacent subchannels and a group 102 of adjacent OFDMA symbols. All resource allocations refer to logical subchannels, and the subchannel offsets in Figure 1 are the frequency domain reference for resource allocations.

In this way, the 2D resource allocation of the IEEE 802.16e system can be visualized as shown in Fig. 1.

On the other hand, the method of distributing the resource area that supports each permutation method will be described below.

Figure 2 shows the case where the resource areas that support each permutation method are separated on the time axis (left side of the figure), and the case where the resource areas that support each permutation method coexist at a specific time (same as above). It is a figure which conceptually shows (right side of the figure).

In the above IEEE 802.16e system, different basic data allocation structures and pilot structures are designed and used for each permutation (distributed / AMC) method. This is because in the conventional IEEE 802.16e system, the permutation methods are separated in time as shown on the left side of Fig. 2, and the structure optimized for each permutation is designed. .. If, as shown on the right side of FIG. 2, various permutation methods coexist in time, that is, if the user can use various permutation methods at a specific time, one unification. Basic data allocation structure and pilot transmission structure may be required.

On the other hand, the slot used as the basic unit of resource allocation in the conventional IEEE 802.16e system as described above is set in the time and frequency domain in a slightly smaller unit for supporting small packet services such as VoIP. The drawback was that the pilot structure was limited and the overhead increased due to signaling, even when relatively large packet services were provided.

<p num="0015"> Therefore, the present invention is directed to a basic signal allocation unit setting method and a signal transmission method using the method, which substantially solves one or more problems due to the above-mentioned limitations and drawbacks of the prior art.</p><p num="0016"> An object of the present invention is to provide a basic signal allocation unit setting method and a signal transmission method using the method. As a result, as shown on the right side of Fig. 2, the basic resources that can be applied in common regardless of the distributed / AMC permutation method, assuming a system in which the user can use various permutation methods at a specific time. We propose an allocation unit, and propose a method for transmitting and receiving signals using the basic resource allocation unit.</p><p num="0017"> Another object of the present invention is to provide a basic signal allocation unit setting method capable of obtaining high system efficiency while minimizing the signaling overhead, and a signal transmission method using the method.</p>

<p num="0018"> In one embodiment of the present invention for solving the above problems, the information bits are divided into basic resource blocks; each of the information bits divided into the basic resource blocks is mapped to the basic resource blocks; The basic resource block unit includes transmitting the mapped information bits as a transmission signal, and the basic resource block unit is "S" OFDMA symbol corresponding to one subframe length or a multiple of one subframe length in the time domain and "N" in the frequency domain. "Including subcarriers (" S "and" N "are natural numbers), the mapping is done by regional resource allocation or distributed resource allocation, and the basic resource block unit is said regional resource allocation and said distributed resource allocation. A signal transmission method commonly used in the above is provided.</p><p num="0019"> Here, the 1 subframe length corresponds to 6 OFDMA symbols, and the S can be 6 or 12.</p><p num="0020"> Further, the "N" can be determined so that the result of multiplying the "N" by a predetermined subcarrier interval corresponds to a predetermined divisor of the system bandwidth, and the predetermined subcarrier interval is 10.9375 kHz. The system bandwidth can be either 5 MHz, 10 MHz or 20 MHz. Also, the predetermined divisor of the system bandwidth can be 200 kHz.</p><p num="0021"> The "N" is 18 or 9, preferably the "S" is 6, and the "N" can be 18.</p><p num="0022"> On the other hand, in another embodiment of the present invention for solving the above problems, the information bits are divided into basic resource block units; each of the information bits divided into the basic resource block units is divided into the basics. Mapping to a resource block; including transmitting the mapped information bits as a transmission signal, the basic resource block unit corresponds to one subframe length or a multiple of one subframe length in the time domain S OFDMA. Including "N" subcarriers in the symbol and frequency domain ("S" and "N" are natural numbers), the mapping is done by regional resource allocation or distributed resource allocation, and the basic resource block unit is said regional. A signal transmission method is provided that is used for resource allocation and the fraction of the basic resource block is used for the distributed resource allocation.</p><p num="0023"> Preferably, the "S" is 6 and the "N" can be 18. Also, the fragment of the basic resource block can include 6 OFDMA symbols and 9 subcarriers.<u style="single">(Item 1)</u><u style="single"> Divide the information bits into basic resource blocks,</u><u style="single"> Each of the information bits divided in the basic resource block unit is mapped to the basic resource block, and the information bits are mapped to the basic resource block.</u><u style="single"> To transmit the mapped information bit as a transmission signal,</u><u style="single">Including</u><u style="single"> The basic resource block unit is</u><u style="single"> Includes "S" OFDMA symbols corresponding to one subframe length or multiples of one subframe length in the time domain and "N" subcarriers in the frequency domain ("S" and "N" are natural numbers).</u><u style="single"> The mapping is performed by regional resource allocation or distributed resource allocation, and the basic resource block unit is a signal transmission method commonly used for the regional resource allocation and the distributed resource allocation.</u><u style="single">(Item 2)</u><u style="single"> The signal transmission method according to item 1, wherein the 1 subframe length corresponds to 6 OFDMA symbols, and the S is 6 or 12.</u><u style="single">(Item 3)</u><u style="single"> The signal transmission method according to item 1, wherein "N" is determined so that the result of multiplying the "N" by a predetermined subcarrier interval corresponds to a predetermined divisor of the system bandwidth.</u><u style="single">(Item 4)</u><u style="single"> The predetermined subcarrier interval is 10.9375 kHz.</u><u style="single"> The signal transmission method according to item 3, wherein the system bandwidth is either 5 MHz, 10 MHz, or 20 MHz.</u><u style="single">(Item 5)</u><u style="single"> The signal transmission method according to item 3, wherein the predetermined divisor of the system bandwidth is 200 kHz.</u><u style="single">(Item 6)</u><u style="single"> The signal transmission method according to any one of items 1, 3, 4 or 5, wherein "N" is 18 or 9.</u><u style="single">(Item 7)</u><u style="single"> The signal transmission method according to item 1, wherein the "S" is 6 and the "N" is 18.</u><u style="single">(Item 8)</u><u style="single"> Divide the information bits into basic resource blocks,</u><u style="single"> Each of the information bits divided in the basic resource block unit is mapped to the basic resource block, and the information bits are mapped to the basic resource block.</u><u style="single"> To transmit the mapped information bit as a transmission signal.</u><u style="single">Including</u><u style="single"> The basic resource block unit is</u><u style="single"> Includes "S" OFDMA symbols corresponding to one subframe length or multiples of one subframe length in the time domain and "N" subcarriers in the frequency domain ("S" and "N" are natural numbers).</u><u style="single"> The mapping is done by regional resource allocation or distributed resource allocation.</u><u style="single"> A signal transmission method in which the basic resource block unit is used for the regional resource allocation, and a fraction of the basic resource block is used for the distributed resource allocation.</u><u style="single">(Item 9)</u><u style="single"> The signal transmission method according to item 8, wherein the S is 6 and the N is 18.</u><u style="single">(Item 10)</u><u style="single"> 9. The signal transmission method of item 9, wherein the basic resource block fragment comprises 6 OFDMA symbols and 9 subcarriers.</u></p>

<p num="0024"> By using the basic signal allocation unit according to the present invention, it is possible to support a small packet service while reducing the signaling overhead, and obtain higher frequency efficiency while making the best use of the basic standards of the existing system. It can be suitably applied to new systems.</p>

<figref num="1">It is a figure which shows the 2D resource allocation concept in OFDMA of an existing IEEE 802.16e system.</figref><figref num="2">The case where the resource areas supporting each permutation method are separated on the time axis (left side) and the case where the resource areas supporting each permutation method coexist at a specific time (right side) are conceptually shown. It is a figure.</figref><figref num="3">It is a figure for demonstrating the basic signal allocation structure.</figref><figref num="4">It is a figure which shows the basic signal allocation unit by one preferable embodiment of this invention.</figref>

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, along with the accompanying drawings, is intended to illustrate exemplary embodiments of the invention and is not intended to indicate the only embodiment in which the invention can be practiced. For example, the following description assumes an IEEE 802.16e system as an existing system and an IEEE 802.16m system as an improved system, but for a system for improving various systems such as 3GPP and 3GPP2. Is also applicable.

On the other hand, the following detailed description includes specific details to provide a complete understanding of the present invention. However, those skilled in the art can understand that the present invention can be implemented without such specific details. For example, the specific numerical values for the resource allocation unit described below may change depending on the system, and even in such a case, the specific principle for deriving each numerical value can be applied in the same manner.

Further, in some cases, in order to avoid obscuring the concept of the present invention, known structures and devices are omitted, or the core functions of each structure and device are shown in the form of a block diagram. In addition, the same components will be described with reference to the same drawing reference throughout the present specification.

In the following description, the "basic signal allocation unit" refers to the smallest basic structure of various signal allocations including data, and performs data / control information allocation and subchannelization at the time of scheduling for data transmission. Applies as the smallest basic unit of the case. Such a basic signal allocation unit is defined as a "Resource Block" in the existing 3GPP LTE system, and a "slot" or "subchannel" in the existing IEEE 802.16e system.

Further, the signal assigned by the above basic signal allocation unit may include not only data but also various signals including control signals, pilots, etc., but hereinafter, as long as it is not confused with other units, it is easy. It can also be called a "basic data allocation unit" for data allocation. The basic signal allocation unit can also be called a "resource block", a "basic resource block", an RB, or the like, like a resource allocation unit of a 3GPP LTE system or the like. This basic signal allocation unit can also be called a'Physical Resource Unit (PRU)'.

On the other hand, when designing the basic signal allocation unit as described above, it is first necessary to determine the granularity of the frequency and time domain.

As mentioned above, it was explained that in existing IEEE 802.16e systems, slots as basic signal allocation units are set in slightly smaller units to support smaller packet services such as VoIP. However, if the basic signal allocation unit is set small for small packet service support, the signaling overhead may increase. Also, in the case of small packet services such as VoIP services, it is common to apply the same MCS for a certain period of time rather than changing the modulation and coding method (MCS) for each basic signal allocation unit. ..

In particular, if the basic signal allocation unit is set small for small packet service support as in the IEEE 802.16e system described above, the signaling overhead may be increased for all other packet service support. However, even if a slightly larger resource allocation unit is set, a method of supporting the existing small packet service is sufficiently possible.

Therefore, it is proposed that the basic signal allocation unit according to the present invention is set to a unit slightly larger than the slot in the above-mentioned IEEE 802.16e system.

FIG. 3 is a diagram for explaining a basic signal allocation structure.

FIG. 3 shows an example in which one signal frame is composed of one or more subframes, and one subframe is composed of six OFDM symbols. If the time domain unit of the basic signal allocation structure is the size of the subframe shown in FIG. 3, that is, the number of OFDM symbols constituting one subframe is the same as the number of OFDM symbols of the basic signal allocation structure. (One-dimensional resource allocation), the basic signal allocation structure is determined only by the number of subcarriers on the frequency axis.

On the other hand, if the number of time domain OFDM symbols in the basic signal allocation structure is different from the number of OFDM symbols that make up the subframe in Figure 3 (two-dimensional resource allocation), the basic data allocation structure is It can be determined by the number of OFDM symbols in the time domain and the number of subcarriers in the frequency domain.

In a preferred embodiment of the invention, as shown in FIG. 3, the minimum resource allocation unit has the number of OFDM symbols corresponding to one subframe in the time domain, and the resource allocation is determined only by the number of subcarriers in the frequency domain. We propose to set the unit. By setting in this way, the signaling overhead can be reduced as compared with the case where the basic signal allocation unit is set two-dimensionally.

On the other hand, as described above, the present invention can be applied to various systems, and in particular, proposes a basic signal allocation structure applied to an IEEE 802.16m system for improving a conventional IEEE 802.16e system. .. In the case of the IEEE 802.16m system, it is required to flexibly support not only the new system of IEEE 802.16m but also the system by IEEE 802.16e and the existing WiMAX (Rel.1.0 or Rel.1.x) (IEEE 802.16m). See -07 / 002r4-TGm System Requirements Document (SRD)). Therefore, it is necessary to refer to the numerology of the existing IEEE 802.16e system even in the design of the new basic signal allocation unit according to the present invention.

First, in the existing IEEE 802.16e system, the subcarrier spacing is 10.9375kHz. Therefore, the number of subcarriers (n) in the frequency domain in the basic signal allocation unit or data allocation unit according to the preferred embodiment of the present invention is a fraction of the system bandwidth when multiplied by this subcarrier interval (10.9375kHz). We propose to make it closer (n * 10.9375kHz a fraction of the system bandwidth) and easily set the bandwidth scheduling (Band-Scheduling).

For example, system bandwidth can have a variety of system bandwidths, including 5MHz, 10MHz, 20MHz, and so on (Scalable Bandwidth). Under the assumption of such a system bandwidth, there can be various candidate subcarriers satisfying the above conditions, and the number of 12 subcarriers and the number of 18 subcarriers will be mainly described below.

Such a number of subcarriers minimizes the signaling overhead and maximizes frequency efficiency in consideration of the coherent bandwidth among the candidates selected from the viewpoint of bandwidth scheduling as described above. It was selected in consideration of the aspect that it is advantageous to allocate resources in a distributed manner even within the basic signal allocation unit by having various divisors. Details of each viewpoint will be described later.

Among the above-mentioned number of subcarriers 12 and 18, in a preferred embodiment of the present invention, it is proposed that the frequency domain unit of the basic signal allocation unit is set to 18 subcarriers. That is, in the present embodiment, it is proposed that the basic signal allocation unit is composed of 18 subcarriers and 6 OFDM symbols.

FIG. 4 is a diagram showing a basic signal allocation unit according to a preferred embodiment of the present invention.

As shown in FIG. 4, the basic signal allocation structure or basic data allocation unit proposed by the present embodiment can function as the smallest basic structure of data / signal allocation, and schedule data / control information allocation and resources. It can be applied as the smallest basic unit when performing resource block channelization or the like. Scheduling (that is, the range to which the control information is applied) can be performed for each basic data allocation unit proposed in the present embodiment, or can be performed in multiples thereof.

In the case of the basic signal allocation unit according to the present embodiment as shown in FIG. 4, a total of 108 subcarriers exist in one basic signal allocation unit, and some of these subcarriers are a data subcarrier, a pilot subcarrier, and a pilot subcarrier. Each can be used as a control signal region.

On the other hand, when 18 subcarriers are used as the frequency domain unit of the basic signal allocation unit according to the present embodiment, assuming the subcarrier interval of 10.9375kHz in the conventional IEEE 802.16e system, the frequency domain unit in the basic signal allocation unit is about. It will be 200kHz and can have a size suitable for band-scheduling. In addition, by including many divisors such as 2, 3, 6, and 9, scheduling can be performed more easily even when the basic signal allocation units are distributed and allocated.

Further, as in the present embodiment, by defining the time domain unit of the basic signal allocation unit as 6 OFDM symbols, the subframe of the new system (for example, IEEE 802.16m) is composed of 6 OFDM symbols and is transmitted. When frames are divided into subframe units, one-dimensional resource allocation can be enabled and overhead can be effectively reduced. On the other hand, according to the present embodiment, FIG. 4 shows a case where the time domain unit of the basic signal allocation unit is composed of 6 OFDM symbols corresponding to one subframe. However, in the present embodiment, the time domain unit is a subframe. It is self-evident to those skilled in the art that it includes cases other than the 6 OFDM symbol as long as it is the same as the unit of.

A brief description of the signal transmission method using the basic resource allocation unit as described above is as follows.

First, a process of segmenting the information bits to be transmitted in the basic signal allocation unit or the basic resource block unit as described above is required. At this time, the information bit string division can be divided in units slightly larger (for example, 18 subcarriers * 6 OFDM symbols) than the division according to the slot size of the existing IEEE 802.16e system. When the information bits are divided in this way, the divided information bits can be mapped to the corresponding basic signal allocation unit and transmitted. At this time, the signal mapped to the basic signal allocation unit and transmitted can include not only data but also control information, pilot, etc., and is conventional IEEE. By setting the allocation and mapping units larger than in the 802.16e system, the signaling overhead can be reduced and the pilot pattern and the like can be defined more efficiently. In addition, the basic resource allocation unit in this case can be applied in a unified manner regardless of the permutation method such as distribution / AMC, and as a result, in a new system (for example, an IEEE 802.16m system), Fig. 2 As shown on the right side of, it can have a structure that can be advantageously applied when designed to support various permutation methods at a particular time. That is, in the structure shown on the right side of FIG. 2, when the basic signal allocation structure according to the present embodiment is applied as the smallest unified transmission unit regardless of the permutation method, there is great flexibility. ).

That is, a logical resource element (LRU) can have the same size as a physical resource element (PRU) and can be a basic unit in both distributed resource allocation and regional resource allocation. However, in some cases, LRUs can have different sizes on the frequency axis. That is, in some cases, LRUs have the same size as PRUs in regional allocations, but LRUs can be the same size as PRUs or fractions of PRUs in distributed resource allocations (eg 1/2, 1 /). 3, 1/6 or 1/9). As mentioned above, the basic signal block can be configured to have many divisors (eg, 2, 3, 6 and 9), so resource allocation of this type is according to the present invention. Can be supported by the definition of PRU. One embodiment of the invention includes a basic signal allocation unit (or PRU) that includes 6 OFDMA symbols and 18 subcarriers, and 6 OFDMA symbols * 18 subcarriers or 6 OFDMA symbols * 9 subcarriers for distributed resource allocation. An allocation unit (ie, LRU) is proposed.

On the other hand, as described above, the basic signal allocation unit proposed by the present embodiment sets the data in the basic signal allocation unit and the pilot subcarrier allocation method in addition to the general method such as the signal transmission method described above. It can be the basis for doing so. At this time, the data in the basic signal allocation unit and the pilot subcarrier allocation method can be applied separately according to the specific number of pilots and the control signal allocation method. That is, the basic signal allocation structure consists of 18 subcarriers and 6 OFDM symbols, and the number of data and pilot subcarriers or pilot patterns in the structure can be applied separately.

Therefore, the number of data subcarriers in the basic signal allocation structure or data allocation structure may or may not be designed for the input size of the CTC (convolutional turbo codes) module (in multiples of 48 or 96). Also good (for example, a Rate-matching module is available).

Table 1 below shows an example of subcarrier configurations that can be used when applying the basic signal allocation units proposed by this embodiment.

<tables num="1"><img id="000002" he="46" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> On the other hand, Table 2 below shows an example of a subcarrier configuration that can be used when the frequency domain unit of the basic signal allocation unit is set to 12 subcarriers according to another embodiment of the present invention.

<tables num="2"><img id="000003" he="45" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> On the other hand, in the following, the case where the basic signal allocation unit composed of 18 subcarriers * 6 OFDM symbols according to the preferred embodiment of the present invention is used and the case where the basic signal allocation unit is configured according to another embodiment are effective. Will be compared and explained in.

First, the effect when the basic signal allocation unit is composed of 18 subcarriers * 6 OFDM symbols according to a preferred embodiment of the present invention is as follows.

First, by setting the frequency subcarrier size (18 subcarriers) suitable for band scheduling as the frequency unit of the basic signal allocation unit, it is possible to minimize the signaling overhead in resource allocation and at the same time show the optimum band scheduling performance. .. For example, when the number of OFDM symbols of the basic signal allocation unit is fixed to 6, the experimental results when compared with the embodiment in which the frequency domain unit is set to 12 subcarrier sizes are as follows.

<tables num="3"><img id="000004" he="41" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="4"><img id="000005" he="67" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> In Table 3 above, RB (12,6) AMC represents the case where the basic signal allocation unit is composed of 12 subcarriers * 6 OFDM symbols and the AMC mode is used according to the embodiment of the present invention, and RB (18,6) ) AMC represents a case where the basic signal allocation unit is composed of 18 subcarriers * 6 OFDM symbols according to a preferred embodiment of the present invention and the AMC mode is used. Also, in Table 4 above, RB (12,6) block-based distributed (S)_d"= 2)" represents the case where the basic signal allocation unit is composed of 12 subcarriers * 6 OFDM symbols and the resource block is divided by 2 according to the embodiment of the present invention, and the block-based distribution mode is used. , 6) block-based distributed (S)_d= 2) represents the case where the basic signal allocation unit is composed of 18 subcarriers * 6 OFDM symbols and the block-based distribution mode in which the resource block is divided by 2 is used according to a preferred embodiment of the present invention.

Based on this, the embodiment using the 18 subcarrier size requires less signaling overhead in resource allocation because the number of basic resource blocks in the overall frequency band is smaller than in the embodiment using the 12 subcarrier size. While having advantages, it can be confirmed from the results in Table 3 above that the band-AMC performance was maintained in almost the same manner.

As can be seen from the results in Table 4, the embodiment using the 18 subcarrier size shows better performance when the distributed permutation mode is applied.

On the other hand, it is possible to assume the number of subcarriers larger than 18 subcarriers, but then the AMC mode performance will be lower than when 18 subcarriers are used. It can be assumed that a subcarrier size smaller than the 12 subcarrier size is used, but this has the disadvantage of increasing the signaling overhead for resource allocation.

Further, when taking into consideration the fact that having a large number of divisors is advantageous, it can be said that the structure in the case of using the 18 subcarriers proposed by the preferred embodiment of the present invention described above is most preferable.

The experimental environments in Tables 3 and 4 above are the results of system-level simulations that match the system environment currently being discussed at the IEEE 802.16m standardization conference, and are shown in Table 5 below for reference. Further, when the pilot overhead is reduced to 5.56% as compared with the existing IEEE 802.16e system, further improved performance can be provided by using the basic signal allocation unit according to the present embodiment.

<tables num="5-1"><img id="000006" he="126" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="5-2"><img id="000007" he="222" wi="159" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables>

<tables num="5-3"><img id="000008" he="112" wi="158" file="JP5312464B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> On the other hand, in the following, basic signal allocation units according to other embodiments of the present invention other than the above 18 subcarriers * 6 OFDM symbol units will be described.

First, in another embodiment of the present invention, it is proposed to use a basic signal allocation unit having 18 subcarrier sizes * 12 OFDM symbol sizes.

For uplink transmission frames / subframes, it may be necessary to define longer subframes (or sets of subframes) than downlink transmission for a variety of reasons. In this case, it is proposed that the number of OFDM symbols in the basic signal allocation structure is defined as 12, which is a multiple of 6. Applying this embodiment, the smallest signal allocation unit for transmitting and scheduling data (or control signals) will have a structure of 18 subcarriers * 12 OFDM symbols. One basic signal allocation structure consists of a total of 216 subcarriers, which can be divided into data subcarriers, pilot subcarriers and control channel subcarriers.

On the other hand, in still another embodiment of the present invention, it is proposed to use a basic signal allocation unit composed of 12 subcarriers * 12 OFDM symbols.

As mentioned above, in the case of uplink transmission frames / subframes, it may be necessary to define longer subframes (or sets of subframes) than downlink transmission for various reasons, and therefore basic signal allocation. The number of OFDM symbols in the structure is defined as 12, and 12 subcarriers can be used as the frequency domain unit.

According to this embodiment, one basic signal allocation unit consists of a total of 144 subcarriers, and these subcarriers can be divided into a data subcarrier, a pilot subcarrier, and a control channel subcarrier.

The above-mentioned detailed description of the preferred embodiment of the present invention has been provided so that those skilled in the art can embody and carry out the present invention. Although the present invention has been described above with reference to the preferred embodiments, a skilled person skilled in the art in the art will appreciate the invention within the scope of the invention described in the appended claims. It is understood that the present invention can be modified and modified in various ways. Therefore, the present invention is not limited to the above embodiments, but has the broadest scope consistent with the principles and novel features disclosed herein.

The basic signal allocation unit according to each embodiment of the present invention and the signal transmission method using the same have a structure suitable for being applied to an IEEE 802.16m system which is an improvement of an existing IEEE 802.16e system. However, in addition to the above-mentioned IEEE 802.16m system, it can be applied by the same principle in various systems for improving various existing wireless communication systems.