KR101749107B1 - Method for transmitting uplink pilot signal in wireless communication system and apparatus therefor - Google Patents

Abstract

A method of transmitting an uplink pilot signal in a wireless communication system is disclosed. Specifically, the method includes the steps of: forming a base unit including a plurality of pilot resource elements (REs) and data resource elements and having a size of 4 subcarriers × 9 OFDMA symbols; setting the plurality of pilot resource elements And transmitting the base unit to a base station, wherein the resource element is a time-frequency resource defined by one OFDMA symbol and one sub-carrier.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a method and apparatus for transmitting uplink pilot signals in a wireless communication system,

The present invention relates to a wireless communication system. More particularly, the present invention relates to a method for transmitting an uplink pilot signal in a wireless communication system and an apparatus therefor.

1 illustrates a wireless communication system. Referring to FIG. 1, a wireless communication system 100 includes a plurality of base stations 110 and a plurality of terminals 120. The wireless communication system 100 may include a homogeneous network or a heterogeneous network. Here, the heterogeneous network refers to a network in which different network entities coexist, such as a macro cell, a femtocell, a picocell, a repeater, and the like. A base station is generally a fixed station that communicates with a terminal, and each base station 110a, 110b, and 110c provides services to specific geographic areas 102a, 102b, and 102c. To improve system performance, the particular area may be divided into a plurality of smaller areas 104a, 104b and 104c. Each smaller area may be referred to as a cell, sector, or segment. In the IEEE 802.16 system, a cell identity (Cell ID or IDCell) is assigned based on the entire system. On the other hand, a sector or a segment identifier is given based on a specific area in which each base station provides a service and has a value of 0 to 2. The terminal 120 is generally distributed in a wireless communication system and can be fixed or mobile. Each terminal can communicate with one or more base stations through an uplink (UL) and a downlink (DL) at any moment. The Node B and the UE may be classified into a Frequency Division Multiple Access (FDMA), a Time Division Multiple Access (TDMA), a Code Division Multiple Access (CDMA), a Single Carrier-FDMA (SC-FDMA), a Multi Carrier- Orthogonal Frequency Division Multiple Access), or a combination thereof. In this specification, the uplink refers to a communication link from a terminal to a base station, and the downlink refers to a communication link from a base station to a terminal.

The present invention provides a method for transmitting an uplink pilot signal in a wireless communication system in a wireless communication system and an apparatus therefor

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, unless further departing from the spirit and scope of the invention as defined by the appended claims. It will be possible.

According to an aspect of the present invention, there is provided a method for transmitting an uplink pilot signal in a wireless communication system, the method comprising: providing a plurality of pilot resource elements (REs) and a data resource element and having a size of 4 subcarriers 3) 占 9 OFDMA symbols (symbol indices 0 to 8); Setting the plurality of pilot resource elements to the base unit; And transmitting the base unit to a base station, wherein the resource element is a time-frequency resource defined by one symbol index and one sub-carrier index.

Advantageously, setting the pilot resource element comprises: placing three pilot resource elements in subcarrier indices 0 and 3 on the frequency axis, respectively; And arranging each of the three pilot resource elements arranged on the frequency axis in at least two symbol index intervals along the time axis.

In this case, the step of setting the pilot resource elements may include the step of arranging each of the plurality of pilot resource elements in different symbol indexes on the time axis.

Further, the step of transmitting the base unit to the base station includes boosting the power of the pilot resource element using the power of the data resource element in the same OFDMA symbol.

According to another aspect of the present invention, there is provided a method of transmitting an uplink pilot signal in a wireless communication system, the method comprising: providing a plurality of pilot resource elements (REs) and a data resource element for each of a first antenna port and a second antenna port (Subcarrier index 0 to 3) × 9 OFDMA symbols (symbol indices 0 to 8), the size of which is 4 subcarriers (subcarrier index 0 to 3); Setting a plurality of pilot resource elements for each of the first antenna port and the second antenna port in the base unit; And transmitting the base unit to a base station, wherein the resource element is a time-frequency resource defined by one symbol index and one subcarrier index.

Preferably, the step of setting the pilot resource element includes arranging two pilot resource elements of the three pilot resource elements for the antenna port 0 at positions where the subcarrier index is 0 and the symbol index is 0 and 8, respectively step; And allocating the remaining one of the three pilot resource elements for the antenna port 0 to a subcarrier index 3 and a symbol index 2 to 6 at an arbitrary position.

More preferably, the step of setting the pilot resource element includes arranging two pilot resource elements of the three pilot resource elements for the antenna port 1 at positions of subcarrier index 3 and symbol index 0 and 8, respectively ; And allocating the remaining one of the three pilot resource elements for the antenna port 1 to a subcarrier index 0 and a symbol index 2 to 6 at an arbitrary position.

Wherein transmitting the base unit to the base station comprises boosting the power of the pilot resource element using power of data RE in the same OFDMA symbol.

In addition, the basic unit may mean a partial usage of subchannel (PUSC) tile, and a transmit diversity technique may be applied in transmitting the basic unit. Here, the transmission diversity scheme is preferably a space frequency block code (SFBC) scheme.

According to embodiments of the present invention, in a wireless communication system, a terminal can efficiently transmit an uplink pilot signal, and a base station can perform channel estimation more effectively using the uplink pilot signal.

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 illustrates a wireless communication system.
2 is a diagram illustrating a conventional IEEE 802.16e tile and pilot structure.
3 is a diagram illustrating a conventional IEEE 802.16e tile and pilot structure.
FIG. 4 is an example of allocating 1 Tx or 1 stream pilot when the uplink PUSC base unit is composed of 4 subcarriers × 6 OFDM (A) symbols in the current IEEE 802.16m system.
FIG. 5 is an example of allocating 2 Tx or 2 stream pilots when the uplink PUSC base unit is composed of 4 subcarriers by 6 OFDM (A) symbols in the current IEEE 802.16m system.
6 to 11 are diagrams illustrating allocation of 1 Tx or one stream pilot when the base unit is composed of 4 subcarriers x 9 OFDM (A) symbols according to an embodiment of the present invention.
12 to 20 are diagrams illustrating allocation of 2 Tx or 2-stream pilots when the base unit is composed of 4 subcarriers by 9 OFDM (A) symbols according to an embodiment of the present invention.
FIG. 21 illustrates a block diagram of a transmitter and a receiver according to an embodiment of the present invention.

The configuration, operation and other features of the present invention can be easily understood by the preferred embodiments of the present invention described with reference to the accompanying drawings. The embodiments described below are examples in which the technical features of the present invention are applied to a system using a plurality of orthogonal subcarriers. For convenience, the present invention will be described using an IEEE 802.16 system. However, the present invention can be applied to various wireless communication systems including 3GPP (3rd Generation Partnership Project) system.

2 illustrates a radio frame structure of the IEEE 802.16m system.

Referring to FIG. 2, the radio frame structure includes a 20-ms super frame (SU0-SU3) supporting 5 MHz, 8.75 MHz, 10 MHz, or 20 MHz bandwidth. The superframe includes four 5ms frames (F0-F3) having the same size and starts with a super frame header (SFH). The superframe header carries essential system parameters and system configuration information.

The frame includes eight sub-frames SF0 - SF7. The subframe is allocated to the downlink or uplink transmission. A subframe includes a plurality of OFDM symbols in the time domain and a plurality of subcarriers in the frequency domain. The OFDM symbol may be referred to as an OFDMA symbol, an SC-FDMA symbol, or the like according to a multiple access scheme. The number of OFDM symbols included in the subframe can be variously changed according to the channel bandwidth and the length of the cyclic prefix.

The type of the subframe can be defined according to the number of OFDM symbols included in the subframe. For example, a Type-1 subframe may be defined to include 6 OFDM symbols, a Type-2 subframe may include 7 OFDM symbols, a Type-3 subframe may include 5 OFDM symbols, and a Type-4 subframe may include 9 OFDM symbols have. One frame may include a sub-frame of the same type, or may include different types of sub-frames.

In particular, the Type-4 subframe including 9 OFDM symbols is applied only to the uplink subframe when the WirelessMAN-OFDMA frame of 8.75 MHz channel bandwidth is supported.

3 is a diagram illustrating a conventional IEEE 802.16e tile and pilot structure.

The current IEEE 802.16e system includes a tile and pilot structure as shown in FIG. 3 as an uplink PUSC (Partial Usage of SubChannel) structure. In particular, FIG. 3 illustrates a case where one transmitting antenna is considered. This uplink PUSC Basic Unit structure has a pilot overhead of 33.33%. In Figure 3, the pilot and data carriers refer to the resource element (RE) to which the pilot and data are allocated, respectively. Each RE represents a time-frequency resource defined by one OFDM (A) symbol and one subcarrier. In the present specification, "pilot (sub) carrier" and "data (sub) carrier" may be mixed with "pilot RE" and "data RE", respectively.

The uplink tile structure used in the current IEEE 802.16e system has a pilot overhead of 33.33% in case of one transmission antenna considering only one transmission antenna. Thus, the overhead of data versus pilot is quite large. This pilot overhead reduces link throughput and results in a performance degradation of the system. Particularly, when the base unit is extended like IEEE 802.16m, it is an issue to reduce the overhead of the pilot.

Embodiments of the present invention provide a basic unit and pilot structure for a structure capable of lowering the pilot overhead in the uplink of the OFDM (A) system and guaranteeing superior performance for channel estimation. In the embodiments of the present invention, pilot REs are assigned on the time axis in consideration of coherent time so that robust channel estimation is possible for low-speed and high-speed cases in the time domain in the basic unit. Also, in the frequency domain, a pilot RE is allocated on the frequency axis in consideration of a coherent bandwidth so that robust channel estimation is possible for various delay spreads. It also provides a basic unit and pilot structure that can improve channel estimation performance using pilots of successive base units when base units are continuously allocated on the time / frequency axis.

 FIG. 4 is an example of allocating 1 Tx or 1 stream pilot when the uplink PUSC base unit is composed of 4 subcarriers × 6 OFDM (A) symbols in the current IEEE 802.16m system.

Referring to FIG. 4, the position of the pilot RE in the 4x6 base unit is such that when the symbol index is 0, the sub-carrier index is 0, the sub-carrier index is 3 when the symbol index is 1, Is 0, and when the symbol index is 5, the subcarrier index is 3.

FIG. 5 is an example of allocating 2 Tx or 2 stream pilots when the uplink PUSC base unit is composed of 4 subcarriers by 6 OFDM (A) symbols in the current IEEE 802.16m system.

Referring to FIG. 5, in the 4x6 base unit, 2 Tx or 2 stream pilots are arranged for each antenna port. The position of the pilot RE with respect to the antenna port 0 is 0 when the symbol index is 0 and the subcarrier index is 3 when the symbol index is 5. The position of the pilot RE with respect to the antenna port 1 is 3 when the symbol index is 0 and the subcarrier index is 0 when the symbol index is 5. The antenna ports can be switched to each other.

Hereinafter, pilot patterns optimized for a type-4 subframe consisting of 4 subcarriers x 9 OFDM (A) symbols are proposed. For convenience of description, the case of allocating 1 Tx or 1 stream pilot to the type-4 subframe and the case of allocating 1 Tx or 1 stream pilot will be described separately.

<When allocating 1 Tx or 1 stream pilot>

6 to 11 are diagrams illustrating allocation of 1 Tx or one stream pilot when the base unit is composed of 4 subcarriers x 9 OFDM (A) symbols according to an embodiment of the present invention.

The subcarriers located at the edge of the tile have less channel measurement performance than the subcarriers located at the center. Particularly, if the pilot pattern is used as a dedicated pilot instead of a common pilot, this performance deterioration becomes even worse. The pilot patterns illustrated in Figures 6-11 below focus on the subcarriers located at these tile edges to avoid a reduction in channel measurement performance caused by extrapolation.

6, pilots are located at both ends of a 4x9 basic unit on the frequency axis and are arranged to maintain the same time interval. The 4x9 base units may be continuously allocated in the frequency domain or the time domain. Specifically, the position of the pilot RE is 0 and 3 when the symbol index is 0 and the sub-carrier indexes are 0 and 3 when the symbol index is 4. When the symbol index is 8, the sub-carrier indexes are 0 and 3 when the symbol index is 8.

In FIG. 7, three pilot REs are respectively located in subcarrier indices 0 and 3 on the frequency axis. Furthermore, the three pilot REs located in the respective subcarriers along the time axis are located at at least two or more symbol index intervals. Also, two or more pilot REs are not located in one symbol index.

In this case, when the symbol index is 0, the subcarrier index is 0. When the symbol index is 2, the subcarrier index is 3. When the symbol index is 3, the subcarrier index is 0. When the symbol index is 5, the subcarrier index is 3. When the symbol index is 6, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

8, when the symbol index of the pilot RE is 0, the subcarrier index is 0. When the symbol index is 1, the subcarrier index is 3. When the symbol index is 7, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

9, when the symbol index of the pilot RE is 0, the sub-carrier indexes are 0 and 3, and when the symbol index is 8, the sub-carrier indexes are 0 and 3, respectively.

10, three pilot REs are respectively located in subcarrier indices 0 and 3 on the frequency axis, as in FIG. Furthermore, the three pilot REs located in the respective subcarriers along the time axis are located at at least two or more symbol index intervals. Also, two or more pilot REs are not located in one symbol index.

An example of the case where the pilot RE is located in this manner is that the subcarrier index is 0 when the symbol index is 0, the subcarrier index is 3 when the symbol index is 1, and 3 when the symbol index is 3. When the symbol index is 0, Is zero. When the symbol index is 4, the subcarrier index is 3. When the symbol index is 6, the subcarrier index is 0. When the symbol index is 7, the subcarrier index is 3.

11, when the symbol index is 1, the sub-carrier index is 0. When the symbol index is 2, the sub-carrier index is 3. When the symbol index is 4, the sub-carrier index is 0. [ When the symbol index is 5, the sub-carrier index is 3. When the symbol index is 7, the sub-carrier index is 0. When the symbol index is 8, the sub-

<When assigning 2 Tx or 2 stream pilots>

12 to 20 are diagrams illustrating allocation of 2 Tx or 2-stream pilots when the base unit is composed of 4 subcarriers by 9 OFDM (A) symbols according to an embodiment of the present invention.

The use of the pilot pattern disclosed in Figs. 12 to 20 has the following advantages.

First, when the wireless communication system supports a transmit diversity scheme among multi-input multi-output (MIMO) techniques, the pilot patterns of FIGS. 12 to 20 can be effectively applied to a space frequency block code (SFBC) . In order to support SFBC, the number of subcarriers for transmitting data and control information except pilots must be even on the frequency axis. In particular, the successive allocation of sub-carriers paired in an OFDM (A) symbol can further improve the performance of the SFBC. In SFBC, if the channels experienced by the paired subcarriers are the same or similar, they can achieve a large gain. Referring to FIG. 14 to FIG. 22, the subcarriers except pilot are continuous in each OFDM (A) symbol and are composed of an even number. Therefore, the pilot patterns of FIGS. 12 to 20 can effectively support the MIMO system.

Second, pilots for antenna ports 0 and 1 are assigned to the same OFDM (A) symbol, thereby improving channel estimation performance by pilot boosting. For example, when transmitting pilot and data for antenna port 0, the pilot RE for antenna port 1 does not transmit anything. In this case, the power allocated to the pilot for antenna port 1 can be additionally assigned to the pilot for antenna port 0. [ Therefore, the channel estimation performance for pilot boosting can be improved. It also helps solve the power balancing problem in uplink transmissions where available power is limited.

Third, efficient channel estimation is possible by maximizing the coherent time and the coherent bandwidth. Specifically, even in an environment with a large channel delay spread, the channel changes little or linearly in four subcarrier units. Also, unless the UE moves at a high speed, the change of channel is not large in units of nine OFDM (A) symbols. In addition, even if the terminal speed increases and a high-speed channel is experienced, the channel linearly changes within 9 OFDM (A) symbol units. Referring to the pilot patterns of Figs. 14-22, the two pilots for each antenna port are located at the diagonal end of the 4x9 base unit. Therefore, the channel estimation performance can be improved by making maximum use of the coherent time and the coherent bandwidth.

Fourthly, by allocating a pilot to the edge of the 4x9 base unit, deterioration of channel estimation performance caused by extrapolation in channel estimation can be prevented.

Referring to FIG. 12, three Tx or two stream pilots are arranged for each antenna port in the 4.times.9 base unit. Specifically, the positions of the two pilot REs among the three pilot REs for antenna port 0 are symbol indexes 0 and 8, and the subcarrier index is zero. Also, the position of the remaining one pilot RE with respect to antenna port 0 is located in subcarrier index 3 and between symbol indices 2 and 6. For example, it is possible to place the remaining one pilot RE for antenna port 0 in symbol index 4 and subcarrier index 3.

In addition, the positions of two pilot REs among the three pilot REs for antenna port 1 are symbol indexes 0 and 8, and the subcarrier index is 3. Also, the position of the remaining one pilot RE with respect to antenna port 1 is located between symbol indices 2 to 6, and the subcarrier index is zero. For example, it is possible to place the remaining one pilot RE for antenna port 0 at symbol index 4 and sub-carrier index 0.

13, when the symbol index is 0, the sub-carrier index is 3. When the symbol index is 3, the sub-carrier index is 3. When the symbol index is 3, the sub- to be. When the symbol index is 5, the subcarrier index is 3. When the symbol index is 6, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

When the symbol index is 3, the sub-carrier index is 0. When the symbol index is 2, the sub-carrier index is 3. When the symbol index is 3, the sub-carrier index is 3. [ When the symbol index is 5, the sub-carrier index is 0. When the symbol index is 6, the sub-carrier index is 3. When the symbol index is 8, the sub-carrier index is 0. [

Referring to FIG. 14, the position of the pilot RE with respect to the antenna port 0 has a subcarrier index of 0 when the symbol index is 0, and a subcarrier index of 3 when the symbol index is 3. When the symbol index is 5, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

On the other hand, the position of the pilot RE with respect to the antenna port 1 is 3 when the symbol index is 0 and the sub-carrier index is 0 when the symbol index is 3. When the symbol index is 5, the subcarrier index is 3, and when the symbol index is 8, the subcarrier index is 0.

Referring to FIG. 15, the position of the pilot RE with respect to the antenna port 0 has a subcarrier index of 0 when the symbol index is 0, and a subcarrier index of 3 when the symbol index is 2. When the symbol index is 6, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

On the other hand, the position of the pilot RE with respect to the antenna port 1 is 3 when the symbol index is 0 and the sub-carrier index is 0 when the symbol index is 2. When the symbol index is 6, the subcarrier index is 3, and when the symbol index is 8, the subcarrier index is 0.

16, when the symbol index is 0, the sub-carrier index is 0. When the symbol index is 8, the sub-carrier index is 3. [ When the symbol index is 0, the sub-carrier index is 3. When the symbol index is 8, the sub-carrier index is 0 at the position of the pilot RE with respect to the antenna port 1. [

Referring to FIG. 17, the positions of the pilot REs for antenna port 0 are 0 and 3 when the symbol index is 0, and 0 and 3 when the symbol index is 7, respectively. When the symbol index is 1, the subcarrier indexes are 0 and 3. When the symbol index is 8, the subcarrier indexes are 0 and 3, respectively.

Referring to FIG. 18, when the symbol index is 0, the subframe index is 0, and when the symbol index is 1, the subframe index is 3. [ When the symbol index is 7, the subcarrier index is 0. When the symbol index is 8, the subcarrier index is 3.

On the other hand, the position of the pilot RE with respect to the antenna port 1 is 3 when the symbol index is 0 and the sub-carrier index is 0 when the symbol index is 1. When the symbol index is 7, the subcarrier index is 3, and when the symbol index is 8, the subcarrier index is 0.

19, when the symbol index is 0, the sub-carrier index is 3. When the symbol index is 1, the sub-carrier index is 3. When the symbol index is 3, the sub-carrier index is 0. When the sub- to be. When the symbol index is 4, the subcarrier index is 3. When the symbol index is 6, the subcarrier index is 0. When the symbol index is 7, the subcarrier index is 3.

The sub-carrier index is 3 when the symbol index is 0. When the symbol index is 3, the sub-carrier index is 3. When the symbol index is 3, the sub-carrier index is 3. When the symbol index is 3, When the symbol index is 4, the subcarrier index is 0. When the symbol index is 6, the subcarrier index is 3. When the symbol index is 7, the subcarrier index is 0.

20, when the symbol index is 1, the sub-carrier index is 3. When the symbol index is 2, the sub-carrier index is 3. When the symbol index is 4, The index is zero. When the symbol index is 5, the sub-carrier index is 3. When the symbol index is 7, the sub-carrier index is 0. When the symbol index is 8, the sub-

When the symbol index is 1, the sub-carrier index is 3. When the symbol index is 2, the sub-carrier index is 0. When the symbol index is 4, the sub-carrier index is 3. [ When the symbol index is 5, the sub-carrier index is 0. When the symbol index is 7, the sub-carrier index is 3. When the symbol index is 8, the sub-carrier index is 0. [

21 illustrates a block diagram of a transmitter and a receiver in accordance with an embodiment of the present invention. In the downlink, the transmitter 2110 is part of the base station and the receiver 2150 is part of the terminal. In the uplink, transmitter 2110 is part of the terminal and receiver 2150 is part of the base station.

At transmitter 2110, transmit (TX) data and pilot processor 2120 encode, interleave, and symbol map data (e.g., traffic data and signaling) to generate data symbols. The processor 2120 also generates pilot symbols to multiplex the data symbols and pilot symbols.

The modulator 2130 generates transmission symbols according to the radio access scheme. The wireless access scheme includes FDMA, TDMA, CDMA, SC-FDMA, MC-FDMA, OFDMA, or a combination thereof. In addition, the modulator 2130 allows data to be transmitted in a frequency domain by using the various permutation methods illustrated in the embodiments of the present invention. A radio frequency (RF) module 2132 processes (e.g., converts, amplifies, filters, and frequency upconverts) the transmission symbols and generates RF signals transmitted through an antenna 2134.

In the receiver 2150, the antenna 2152 receives the signal transmitted from the transmitter 2110 and provides it to the RF module 2154. RF module 2154 processes (e.g., filters, amplifies, frequency downconverts, digitizes) the received signal to provide input samples.

A demodulator 2160 demodulates the input samples to provide a data value and a pilot value. Channel estimator 2180 derives the channel estimate based on the received pilot values. The demodulator 2160 also performs data detection (or equalization) on the received data values using the channel estimate and provides data symbol estimates for the transmitter 2110. In addition, the demodulator 2160 may reverse the various permutation methods illustrated in the embodiments of the present invention to rearrange the distributed data in the frequency domain and the time domain in the original order. Rx data processor 2170 symbol demaps, deinterleaves, and decodes the data symbol estimates and provides decoded data.

In general, the processing by the demodulator 2160 and the Rx data processor 2170 at the receiver 2150 is complementary to the processing by the modulator 2130 and the Tx data and the pilot processor 2120, respectively, at the transmitter 2110.

Controllers / processors 2140 and 2190 supervise and control the operation of various processing modules present in transmitter 2110 and receiver 2150, respectively. Memory 2142 and 2192 store program codes and data for transmitter 2110 and receiver 2150, respectively.

The module illustrated in FIG. 21 is for illustrative purposes, and the transmitter and / or receiver may further include necessary modules, some modules / functions may be omitted or separated into different modules, Lt; / RTI &gt;

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.

In this document, the embodiments of the present invention have been mainly described with reference to the data transmission / reception relationship between the terminal and the base station. The specific operation described herein as being performed by the base station may be performed by its upper node, in some cases. That is, it is apparent that various operations performed for communication with a terminal in a network including a plurality of network nodes including a base station can be performed by a network node other than the base station or the base station. A 'base station' may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, and the like. The term 'terminal' may be replaced with terms such as User Equipment (UE), Mobile Station (MS), and Mobile Subscriber Station (MSS).

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, processors, controllers, microcontrollers, microprocessors, and 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 of the invention. 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.

The present invention can be applied to a wireless communication system. Specifically, the present invention can be applied to a wireless mobile communication device used for a cellular system.

Claims (13)

A method for transmitting an uplink pilot signal in a wireless communication system,
A plurality of pilot resource elements (REs) and a data resource element for each of the first antenna port and the second antenna port and having a size of 4 subcarriers (subcarrier index 0 to 3) × 9 OFDMA symbols (symbol index 0 To 8);
Setting a plurality of pilot resource elements for each of the first antenna port and the second antenna port in the base unit; And
And transmitting the base unit to a base station,
Wherein the resource element is a time-frequency resource defined by one symbol index and one subcarrier index,
Wherein setting the pilot resource element comprises:
Arranging two pilot resource elements of the three pilot resource elements for the first antenna port at positions where the subcarrier index is 0 and the symbol index is 0 and 8, respectively;
Placing the remaining one of the three pilot resource elements for the first antenna port at a subcarrier index 3 and at any one of the symbol indices 2 to 6;
Placing two pilot resource elements out of the three pilot resource elements for the second antenna port at positions where the subcarrier index is 3 and the symbol index is 0 and 8, respectively; And
And arranging the remaining one of the three pilot resource elements for the second antenna port at a subcarrier index 0 and at any one of the symbol indices 2 to 6,
A method for transmitting an uplink pilot signal. The method according to claim 1,
Wherein the step of transmitting the base unit to a base station comprises:
And boosting the power of the pilot resource element using power of a data resource element in the same OFDMA symbol.
A method for transmitting an uplink pilot signal. The method according to claim 1,
Wherein a transmit diversity scheme is applied to the base unit,
A method for transmitting an uplink pilot signal. The method of claim 3,
The transmission diversity scheme may include:
A space frequency block code (SFBC) technique,
A method for transmitting an uplink pilot signal. delete delete delete delete delete delete delete delete delete

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