KR100937029B1 - Method for transmitting signal - Google Patents

Abstract

In the signal transmission method according to the present invention, a plurality of sync channel symbols and a plurality of broadcast channel symbols are allocated to a plurality of symbol sections, respectively, the plurality of sync channel symbols and the plurality of sync channel symbols are allocated adjacent to the broadcast. Applying a first transmit diversity scheme to a channel symbol, applying a second transmit diversity scheme to the broadcast channel symbol allocated apart from the plurality of sync channel symbols, and the plurality of sync channel symbols; Transmitting the plurality of broadcast channel symbols. Accordingly, the time diversity gain can be maximized by applying various transmission diversity schemes of BCH information according to the distance between SCH information and BCH information. In addition, different phase shifts may be applied according to sectors to efficiently remove interference from adjacent sectors at sector boundaries.

SCH, BCH, sector, precoding vector, cyclic delay value, frequency-space coding, subframe

Description

Signal transmission method {METHOD FOR TRANSMITTING SIGNAL}

The present invention relates to a method of transmitting a signal.

Currently, 3GPP (3rd Generation Partnership Project) standardization of wireless transmission technology based on orthogonal frequency division multiplexing (OFDM) under the name of 3G Long Term Evolution (LTE).

In a multi-cell system using OFDM, a user should be able to efficiently receive information necessary for initial system access through a broadcast channel. In addition, all users in any sector must satisfy the requirements for reception quality of broadcast channel information, for example, block error rate and delay rate.

However, when a user is at a sector boundary within the same cell, there is a problem that this requirement is not satisfied due to the interference from adjacent sectors.

An object of the present invention is to provide a transmit diversity method for effective demodulation of BCH information. Another object of the present invention is to provide a signal transmission method and a signal reception method for enhancing BCH information reception quality of a mobile station at a sector boundary of a cell.

In the signal transmission method according to the present invention, a plurality of sync channel symbols and a plurality of broadcast channel symbols are allocated to a plurality of symbol sections, respectively, the plurality of sync channel symbols and the plurality of sync channel symbols are allocated adjacent to the broadcast. Applying a first transmit diversity scheme to a channel symbol, applying a second transmit diversity scheme to the broadcast channel symbol allocated apart from the plurality of sync channel symbols, and the plurality of sync channel symbols; Transmitting the plurality of broadcast channel symbols.

The applying of the first transmit diversity scheme may include applying a plurality of first precoding vectors to a plurality of transmit antennas, and applying the plurality of first precoding vectors to the plurality of sync channel symbols, respectively. And applying the plurality of first precoding vectors identical to the plurality of sync channel symbols to the broadcast channel symbols allocated adjacent to the plurality of sync channel symbols.

The applying of the second transmit diversity scheme may include: respectively corresponding a plurality of second precoding vectors to the plurality of transmit antennas, and the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols. And applying the plurality of second precoding vectors to each.

The applying of the second transmit diversity scheme may include setting a plurality of cyclic delay values corresponding to the plurality of transmit antennas, and applying the plurality of cyclic delay values to the plurality of broadcast channel symbols, respectively. It may include.

The plurality of first and second precoding vectors and the plurality of cyclic delay values may be determined according to sectors.

The plurality of first and second precoding vectors and the plurality of cyclic delay values may be determined according to a subframe to which the broadcast channel symbol is allocated.

The plurality of first and second precoding vectors and the plurality of cyclic delay values may be determined according to the symbol intervals of the plurality of broadcast channel symbols and the plurality of sync channel symbols.

In the applying of the second transmission diversity scheme, a frequency space diversity scheme may be applied to the broadcast channel symbols allocated to be spaced apart from the plurality of synchronization channel symbols.

On the other hand, in the signal transmission method according to the present invention, the step of assigning a plurality of synchronization channel symbols and a plurality of broadcast channel symbols to a plurality of symbol intervals, respectively, setting a plurality of precoding vectors for a plurality of transmit antennas, the plurality of Applying each of the plurality of precoding vectors to the synchronization channel symbols of, applying different transmission diversity schemes to the plurality of broadcast channel symbols according to the distance to the plurality of synchronization channel symbols, and the plurality of And transmitting the synchronization channel symbol and the plurality of broadcast channel symbols.

The same precoding vector as the plurality of sync channel symbols may be applied to the plurality of broadcast channel symbols adjacent to the plurality of sync channel symbols.

A precoding vector different from the plurality of sync channel symbols may be applied to the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols.

Respectively setting a plurality of cyclic delay values in the plurality of transmit antennas, and applying the plurality of cyclic delay values to the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols, respectively. Can be.

Frequency-space coding may be performed on the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols.

According to the present invention, it is possible to maximize the time diversity gain in the BCH Transmission Time Interval (TTI) by applying various transmission diversity schemes of BCH information according to the distance between SCH information and BCH information. In addition, different phase shifts may be applied according to sectors to efficiently remove interference from adjacent sectors at sector boundaries.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise. In addition, the terms “… unit”, “… unit”, “module”, etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. have.

In this specification, a mobile station (MS) includes a terminal, a mobile terminal (MT), a subscriber station (SS), a portable subscriber station (PSS), and a user equipment. It may also refer to a user equipment (UE), an access terminal (AT), and the like, and may include all or some functions of a terminal, a mobile terminal, a subscriber station, a portable subscriber station, a user device, an access terminal, and the like.

In the present specification, a base station (BS) is an access point (AP), a radio access station (Radio Access Station, RAS), a Node B (Node B), a base transceiver station (Base Transceiver Station, BTS), MMR ( Mobile Multihop Relay) -BS and the like, and may include all or part of functions such as an access point, a radio access station, a Node B, a base transceiver station, and an MMR-BS.

Hereinafter, a communication system according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

1 is a diagram illustrating a communication system according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a base station according to an embodiment of the present invention.

Referring to FIG. 1, the communication system includes a base station 100 and a mobile station 200. Referring to FIG. 2, the base station 100 includes a first sector transmitter 110, a second sector transmitter 120, and The third sector transmitter 130 is included.

Base station 100 manages cell 10. The cell 10 is composed of a first sector 11, a second sector 12, and a third sector 13. In the embodiment of the present invention, the cell 10 is described as being composed of three sectors. Alternatively, the cell 10 may be composed of two or four sectors. Base station 100 communicates with mobile station 200 within cell 10.

The first sector transmitter 110, the second sector transmitter 120, and the third sector transmitter 130 manage the first sector 11, the second sector 12, and the third sector 13, respectively. . That is, the first sector transmitter 110 communicates with the mobile station in the first sector 11, the second sector transmitter 120 communicates with the mobile station in the second sector 12, and the third sector transmitter 130 Communicate with the mobile station in the third sector 13.

The first sector transmitter 110, the second sector transmitter 120, and the third sector transmitter 130 each have a sync channel to the first sector 11, the second sector 12, and the third sector 13. Synchronization channel (SCH) information and broadcast channel (BCH) information are transmitted. SCH information varies from sector to sector, and BCH information is common to all sectors. That is, SCH information is distinguished according to sectors, and BCH information is distinguished according to cells. The BCH information is transmitted on a predefined independent physical channel known to all mobile stations 200. The first sector transmitter 110, the second sector transmitter 120, and the third sector transmitter 130 are synchronized so that the mobile station 200 can demodulate the BCH information through soft-combining.

In an embodiment of the present invention, a sector to which the mobile station 200 belongs to among the plurality of sectors constituting the cell 10 is called a home sector, and the received power of a threshold value or more adjacent to the mobile station among the sectors excluding the home sector. A sector for transmitting a signal is called a target sector.

Hereinafter, a sector transmitter according to an embodiment of the present invention will be described with reference to FIGS. 3 to 7.

3 is a block diagram illustrating a sector transmitter according to an embodiment of the present invention.

Referring to FIG. 3, a sector transmitter 400 according to an embodiment of the present invention transmits a signal to an s-th sector, and includes a BCH symbol generator 410, a SCH symbol generator 420, and other channel symbol generators. 430, an OFDM symbol mapping unit 440, a switch 450, a first transmitter 460a, a second transmitter 460b, a first antenna 470a, and a second antenna 470b.

4 is a flowchart illustrating a sector transmission method according to an embodiment of the present invention.

First, the BCH symbol generator 410 generates and outputs a plurality of BCH symbols.

Specifically, the channel encoder 411 performs channel coding, such as turbo coding or convolutional coding, on the BCH data to generate and output channel encoded BCH data.

The interleaver 412 generates and outputs interleaved BCH data by changing the order of channel encoded BCH data output by the channel encoder 411.

The digital modulator 413 performs digital modulation such as binary phase shift key (BPSK) and quadrature amplitude modulation (QAM) on the interleaved BCH data output from the interleaver 412. A plurality of BCH symbols are generated and output (S201).

등이 될 수 있다.On the other hand, the SCH symbol generation unit 420 generates and outputs a plurality of SCH symbols (S203). The SCH symbol generator 420 generates and outputs an SCH symbol vector by scrambling the SCH symbol using the SCH scrambling code according to the number of SCH symbols included in the subframe in which the SCH symbol exists. The value of the SCH symbol can be changed according to the specification, 1 or

And so on.

On the other hand, the other channel symbol generator 430 generates and outputs a plurality of other channel symbols (S205).

The OFDM symbol mapping unit 440 outputs a plurality of mapped symbols by mapping a plurality of BCH symbols, a plurality of SCH symbols, and a plurality of other channel symbols to a time domain and a frequency domain. That is, the OFDM symbol mapping unit 440 performs time division multiplexing and frequency division multiplexing on the plurality of BCH symbols, the plurality of SCH symbols, and the plurality of other channel symbols (S207).

Hereinafter, a mapping method of the OFDM symbol mapping unit 440 will be described with reference to FIG. 5.

5 illustrates a downlink frame in which SCHs and BCHs are mapped according to various embodiments of the present disclosure.

The sector transmitter 300 may use various bandwidths such as 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz as the system bandwidth.

Referring to FIG. 5, the downlink frame according to the embodiment of the present invention includes 20 subframes. SCH and BCH are mapped to the same frequency of the system bandwidth, for example, 1.25 MHz. Accordingly, the mobile station 200 does not need to perform blind detection on the BCH bandwidth to demodulate the BCH symbol.

When the number of SCHs is two, one is called a primary synchronous channel (P-SCH) and the other is called a secondary chronization channel (S-SCH).

The OFDM symbol mapping unit 440 allocates a plurality of P-SCH symbols and a plurality of S-SCH symbols to two adjacent OFDM symbol intervals by time division multiplexing (TDM). In this case, the S-SCH may be used for channel estimation or, alternatively, the P-SCH may be used for channel estimation.

The OFDM symbol mapping unit 440 multiplexes BCH information into two subframes during one downlink frame period. The BCH information is transmitted to the mobile station 200 in the form of a packet. One BCH information packet may be multiplexed in one frame and transmitted every 10 msec, and may be multiplexed in two or more frames and 20 msec, 30 msec, or 40 msec May be sent.

An embodiment of the present invention may use a multiplexing method for transmitting BCH information through a unicast channel, or a multiplexing method for transmitting a BCH information through a multicast channel, a multimedia broadcast and multicast service (MBMS) channel, and the like. Can also be used.

According to FIG. 5, the OFDM symbol mapping unit 440 maps the S-SCH symbol and the P-SCH symbol to the last OFDM symbol interval, that is, the fifth and sixth symbol intervals, at intervals of ten subframes. do. The OFDM symbol mapping unit 440 maps a BCH symbol, a BCH symbol, and a downlink reference signal (DL RS) symbol to OFDM symbol intervals other than the OFDM symbol interval to which the S-SCH symbol and the P-SCH symbol are mapped. do.

According to the location of the mapped BCH symbol as shown in FIG. 5, the switch 450 outputs to the first / second transmitters 460a / 460b through various transmission diversity schemes (S209).

The switch 450 applies the same transmit diversity scheme as that of the SCH symbol to the BCH symbol disposed in the section adjacent to the SCH symbol, for example, the BCH symbol disposed in the third and fourth symbol sections, and the other BCH symbol and the reference. For the symbol, the same or different transmit diversity scheme as the SCH symbol is applied.

According to an embodiment of the present invention, the switch 450 applies a precoding vector switching diversity scheme to a SCH symbol, a BCH symbol and a reference symbol adjacent thereto, and precoding vector switching diversity to other BCH symbols and a reference symbol. The technique can be applied.

Hereinafter, a transmission diversity scheme according to precoding vector switching will be described with reference to FIGS. 6 and 7.

6 and 7 are cell configuration diagrams according to a precoding vector switching technique.

In FIG. 6 and FIG. 7, it is assumed that each sector transmitter 400 has two or four antennas and one cell includes three sectors.

The switch 450 applies a precoding vector to the BCH symbol, B _{k, i, c} (s) in the subframe s containing the BCH symbol, as shown in Equation 1, and transmits a transmission signal for each transmission antenna a, T _{k, i,} produces _{a, c} (s)

[Equation 1]

Here, k denotes a frequency domain subcarrier index containing BCH information B _{k, i, c} (s) for each sector c. In addition, Ø _{1, a} (i, s) denotes a phase weighting value of a precoding vector applied to a BCH symbol in an OFDM symbol i of a subframe s containing a BCH symbol and maximizes time diversity gain. Mean phase shift value.

In this case, a relationship of Ø _1,0 (i, s) = 0 and Ø _{1, a} (i, s) = a · Ø _1,1 (i, s) may be satisfied.

The switch 450 applies the same Ø _{1, a} (i, s) as the SCH symbol to the BCH symbol located in close proximity to the SCH symbol, for example, the BCH symbol arranged in the third and fourth symbol intervals. The same or different values of Ø _{1, a} (i, s) apply to the BCH symbol.

That is, Ø _{1, a} (0, s) = Ø _{1, a} (1, s) = Ø _{1, a} (2, s) ≠ Ø _{1, a} (3, s) = Ø _{1, a} (4, s The phase weighting value of the precoding vector may be applied according to the symbol interval to satisfy) = Ø _{1, a} (5, s) = Ø _{1, a} (6, s).

The phase weighting value of the precoding vector has a different value for each subframe to maximize the time diversity gain.

When the BCH symbol is arranged in the 0th and 10th subframes as shown in FIG. 5, Ø _{1, a} (i, 0) ≠ Ø _{1, a} (i, 10), i = 0,1,2,3, Meets 4,5,6

As an example of such a precoding vector phase weighting value, Ø _{1, a} (0,0) = Ø _{1, a} (1,0) = Ø _{1, a} (2,0) = 0, Ø _{1, a} (3 , 0) = Ø _{1, a} (4,0) = Ø _{1, a} (5,0) = Ø _{1, a} (6,0) = π, Ø _{1, a} (0,10) = Ø _{1, a} (1,10) = Ø _{1, a} (2,10) = π, Ø _{1, a} (3,10) = Ø _{1, a} (4,10) = Ø _{1, a} (5,10) = Ø _{1, a} (6,10) = 0 can be satisfied. The reverse is also possible.

As another example, Ø _{1, a} (0,0) = Ø _{1, a} (1,0) = Ø _{1, a} (2,0) = π / 2, Ø _{1, a} (3,0) = Ø _{1, a} (4,0) =

Ø _{1, a} (5,0) = Ø _{1, a} (6,0) =-π / 2, Ø _{1, a} (0,10) = Ø _{1, a} (1,10) = Ø _{1 , a} (2,10) =-π / 2, Ø _{1, a} (3,10) = Ø _{1, a} (4,10) = Ø _{1, a} (5,10) = Ø _{1, a} (6, 10) = π / 2 may be satisfied. The reverse is also possible.

In this way, phase weighting values of precoding vectors having orthogonality are applied between the SCH symbol and the adjacent BCH symbol and relatively spaced BCH symbols, and the orthogonality is applied between the subframes in which the BCH symbol is disposed.

Therefore, when demodulating the 3rd and 4th BCH symbols, the SCH channel can be used for channel estimation for BCH demodulation, and demodulation of some of the BCH channel information can be performed without information on the number of transmitting antennas.

In this case, as shown in FIG. 6, the switch 450 may apply the phase weighting value of the same precoding vector to the symbol for all sectors included in each cell.

Meanwhile, the switch 450 may apply the phase weighting value of the precoding vector to correspond to the sector of each cell 10 as shown in FIG. 7.

That is, the precoding phase weighting value is determined according to the transmit antenna and the sector in the corresponding subframe.

The transmission signal for each transmission antenna a, T _{k , i, a, c} (s) (a = 0,1) output through the switch 450 satisfies Equation 2.

[Equation 2]

At this time, Ø _{2, a} (c) = a · Ø _{2, 1} (c) can be satisfied.

For example, if the number of sectors in a cell is 3, Ø _{2, a} (0) = 0, Ø _{2, a} (1) = 2π / 3, Ø _{2, a} (2) = 4π / 3 Ø _{2, a} (c) may be applied as 0, π, π / 2 (−π / 2) depending on the sector. Further, when the number of sectors in the cell is 6, the case where the number of sectors is 3 is extended, so that Ø _{2, a} (s) is 0, 2π / 3, 4π / 3, 0, 2π / 3, 4π / for each sector. 3, or 0, π, π / 2, 3π / 2, 0, π or π / 2, 3π / 2, 0, π, π / 2, 3π / 2 can be applied.

When different phase shifts are applied to the sectors as described above, even if the phase weighting values for the precoding vectors and the phase shift values for the time diversity are the same, the phase shift values for the spatial diversity gain are different for each sector. If the spatial correlation between the transmitting antennas is relatively large, different beams are formed. Therefore, interference from adjacent sectors can be effectively prevented.

As such, the sector transmitter 400 applies precoding vector switching to the BCH symbol to lower the block error rate of the BCH information to improve reception quality.

On the other hand, the switch 450 may apply the precoding vector transmit diversity scheme to the SCH symbol and the BCH symbol adjacent to the SCH symbol, and to apply the cyclic delay transmit diversity scheme to the other BCH symbols. have.

The switch 450 applies the cyclic delay value to the BCH symbol and the reference symbol in the 4th to 6th symbol intervals of FIG. 5 to transmit a transmission signal for each transmitting antenna, T _{k, i, a, c} (s) Create

[Equation 3]

Here, k denotes a frequency domain subcarrier index containing BCH information B _{k , i, c} (s) for each sector c. In addition, θ _a (k, s) means a cyclic delay value applied to a subframe s including a BCH symbol or a reference symbol for each antenna a.

As shown in Equation 3, the switch 450 may apply the same cyclic delay value to all sectors included in each cell 10.

Meanwhile, the switch 450 may further apply a phase shift value that further maximizes the time diversity gain and also obtains the spatial diversity gain while applying the cyclic delay value.

Specifically, the switch 450 generates a transmission signal for each transmission antenna a, T _{k, i, a, c} (s) (a = 0,1) satisfying Equation (4).

[Equation 4]

Here, Ø _{1, a} (i, s) denotes a phase weighting value of the precoding vector applied to the BCH symbol in the OFDM symbol i of the subframe s containing the BCH symbol and maximizes the time diversity gain. Ø _{2, a} (c) means a phase shift value for maximizing different spatial diversity gains for each sector for the BCH symbol transmitted through the transmission antenna a.

For example, the relationship of Ø _{1, a} (i, s) = a · Ø _1,1 (i, s) and a = 1,2,3 may be satisfied.

This Ø _{1, a} (i, s) can be equally applied to all sectors.

Further, the relationship of Ø _{2, a} (c) = a Ø _2,1 (c) and a = 1, 2, 3 can also be satisfied.

For example, if the number of sectors in cell 10 is 3, Ø _{2, a} (0) = 0, Ø _{2, a} (1) = 2π / 3, Ø _{2, a} (2) = 4π / 3 Ø _{2, a} (c) may be applied as 0, π, π / 2 (-π / 2) depending on the sector. Further, when the number of sectors in the cell is 6, the case where the number of sectors is 3 is extended, so that Ø _{2, a} (s) is 0, 2π / 3, 4π / 3, 0, 2π / 3, 4π / for each sector. 3, or 0, π, π / 2, 3π / 2, 0, π or π / 2, 3π / 2, 0, π, π / 2, 3π / 2 can be applied.

When different phase shifts are applied to the sectors as described above, even if the precoding phase weighting value and the phase shifting value for temporal diversity are the same, the phase shifting values for the spatial diversity gain are different from sector to sector. When the spatial spatial correlation is relatively large, different beams are formed. Therefore, interference from adjacent sectors can be effectively prevented.

As described above, the sector transmitter 400 applies cyclic delay switching to the BCH symbol allocated to be spaced apart from the SCH symbol to lower the block error rate of the BCH information to improve reception quality.

Meanwhile, the switch may apply the precoding vector transmit diversity scheme to the SCH symbol and the BCH symbol adjacent to the SCH symbol, and apply the frequency-space block coding diversity scheme to the other BCH symbols. .

Hereinafter, a frequency-space block coding diversity scheme will be described with reference to FIG. 8.

8 shows symbol grouping and mapping for a frequency-space block coding (SFBC) diversity scheme.

As shown in FIG. 8, the switch 450 groups complex symbols of the mapped BCH channel in units of two symbols. The first symbol of the m th group is called m ₀ and the second symbol is m ₁ . The switch 450 generates four transmission signals by performing frequency-space coding on each group of symbols in two spatial domains (transmission antennas) and two frequency domains.

In this case, each transmission signal may satisfy Equation 5.

[Equation 5]

을 출력하고, 제2 공간 영역(제2 안테나)을 위해

을 출력한다. 또한 스위치(450)는 다른 주파수 영역에서 제1 공간 영역(제1 안테나)을 위해

을 출력하고, 제2 공간 영역(제2 안테나)을 위해

을 출력한다.That is, the switch 450 is configured for the first spatial domain (first antenna) in one of the two frequency domains.

For the second spatial region (second antenna)

Outputs The switch 450 is also used for the first spatial domain (first antenna) in another frequency domain.

For the second spatial region (second antenna)

Outputs

Meanwhile, as illustrated in FIG. 9, the OFDM symbol mapping unit 440 may map downlink frames in a different manner from that of FIG. 5.

9 shows a downlink frame in which SCHs and BCHs are mapped according to another embodiment of the present invention.

As shown in FIG. 9, when the BCH symbol is multiplexed into a plurality of subframes during one frame, the OFDM symbol mapping unit 440 may be multiplexed into two consecutive subframes or may be multiplexed into one subframe during one frame. have. For example, the OFDM symbol mapping unit 440 may map BCH symbols to the first and second subframes of one frame.

In this case, the switch 450 applies the phase weighting value of the precoding vector described above in the OFDM symbol interval unit in which the SCH symbol and the BCH symbol are multiplexed.

That is, transmission by transmission antenna by applying a precoding vector switching transmission diversity scheme as shown in Equation 1 to the frequency domain BCH symbols B _{k, i, c} (s) in a subframe containing the BCH symbol (s = 0). Generate signals T _{k, i, a, c} (s).

Alternatively, as shown in Equation 2, a transmission signal may be generated by further applying a phase shift value for each sector to ensure spatial diversity.

In the transmission signal T _{k, i, a, c} (s) of Equation 2 _, BCH symbols i in subframe s containing BCH information for each transmission antenna a, which is the phase shift value of the precoding vector, are shown in FIG. It means the applied precoding phase weighting value and the phase shift value for maximizing time diversity gain.

In the example of the present invention, it may be differently applied to have orthogonality in units of OFDM symbols for time diversity gain. That is, phase shift values having orthogonality between OFDM symbols are allocated.

As such, when different phase shift values are allocated according to sectors, when the BCH information is different between sectors, that is, sector-specific information, interference from adjacent sectors is effectively reduced. In addition, when the BCH information is the same for sectors in the same cell, that is, the information for the common cell, there is an effect of increasing the soft combining gain.

Even in the case of OFDM symbol mapping as shown in FIG. 9, a precoding vector transmit diversity scheme, a cyclic delay transmit diversity scheme, or a frequency-space block coding is applied to a BCH symbol spaced apart from an SCH symbol. Diversity can be applied. In this case, each weight value may vary in units of symbol intervals as described above.

Referring back to FIG. 4, the first and second transmitters 460a and 460b receive a plurality of channel symbols from the switch 450 and transmit them to the s-th sector through the first and second antennas 470a and 470b. It transmits (S211).

The first / second transmitters 460a / 460b scramble the BCH symbol with a sector-specific scrambling code or a cell-specific scrambling code to generate and output a plurality of scrambled symbols. Since scrambling the SCH symbol may make initial cell search difficult, the SCH symbol is not scrambling with a sector-specific scrambling code or a cell-specific scrambling code.

The first and second transmitters 460a and 460b generate a time domain signal by performing fast Fourier inverse transform on the scrambled symbols and insert a guard interval such as a cyclic prefix (CP). Next, the first and second transmitters 460a and 460b convert the amplified signals into high frequency signals and amplify them and transmit them to the mobile station 200 through the first and second antennas 470a and 470b.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

1 is a diagram illustrating a communication system according to an embodiment of the present invention.

2 is a diagram illustrating a base station according to an embodiment of the present invention.

3 is a block diagram illustrating a sector transmitter according to an embodiment of the present invention.

4 is a flowchart illustrating a sector transmission method according to an embodiment of the present invention.

5 shows a downlink frame in which SCHs and BCHs are mapped according to an embodiment of the present invention.

6 and 7 are cell configuration diagrams according to a precoding vector switching technique.

8 shows grouping and mapping according to a frequency-space diversity technique.

9 shows a downlink frame in which SCHs and BCHs are mapped according to another embodiment of the present invention.

Claims (13)

Allocating a plurality of sync channel symbols and a plurality of broadcast channel symbols to a plurality of symbol intervals, respectively; Applying a first transmit diversity scheme to the plurality of sync channel symbols and the broadcast channel symbols allocated adjacent to the plurality of sync channel symbols; Applying a second transmit diversity scheme to the broadcast channel symbols spaced apart from the plurality of sync channel symbols; and Transmitting the plurality of sync channel symbols and the plurality of broadcast channel symbols Signal transmission method comprising a. The method of claim 1, Applying the first transmit diversity scheme is Respectively corresponding a plurality of first precoding vectors to a plurality of transmit antennas, Applying each of the plurality of first precoding vectors to the plurality of synchronization channel symbols, and Applying the plurality of first precoding vectors equal to the plurality of sync channel symbols to the broadcast channel symbols allocated adjacent to the plurality of sync channel symbols Containing Signal transmission method. The method of claim 2, Applying the second transmit diversity scheme is Respectively corresponding a plurality of second precoding vectors to the plurality of transmit antennas, and Applying the plurality of second precoding vectors to the plurality of broadcast channel symbols allocated spaced apart from the plurality of sync channel symbols, respectively. Containing Signal transmission method. The method of claim 2, Applying the second transmit diversity scheme is Setting a plurality of cyclic delay values corresponding to the plurality of transmit antennas, respectively, and Applying the plurality of cyclic delay values to the plurality of broadcast channel symbols, respectively. Containing Signal transmission method. The method of claim 4, wherein The plurality of first and second precoding vectors and the plurality of cyclic delay values are determined according to sectors. Signal transmission method. The method of claim 4, wherein The plurality of first and second precoding vectors and the plurality of cyclic delay values are determined according to a subframe to which the broadcast channel symbol is assigned. Signal transmission method. The method of claim 4, wherein And the plurality of first and second precoding vectors and the plurality of cyclic delay values are determined according to the symbol intervals of the plurality of broadcast channel symbols and the plurality of synchronization channel symbols. The method of claim 2, Applying the second transmit diversity scheme is And a frequency space diversity scheme is applied to the broadcast channel symbols spaced apart from the plurality of sync channel symbols. Allocating a plurality of sync channel symbols and a plurality of broadcast channel symbols to a plurality of symbol intervals, respectively; Setting a plurality of precoding vectors for each of the plurality of transmit antennas, Applying each of the plurality of precoding vectors to the plurality of synchronization channel symbols, Applying different transmit diversity schemes to the plurality of broadcast channel symbols according to distances to the plurality of sync channel symbols, and Transmitting the plurality of sync channel symbols and the plurality of broadcast channel symbols Signal transmission method comprising a. The method of claim 9, And applying the same precoding vector as the plurality of sync channel symbols to the plurality of broadcast channel symbols adjacent to the plurality of sync channel symbols. The method of claim 10, And applying a different precoding vector from the plurality of sync channel symbols to the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols. The method of claim 10, Setting a plurality of cyclic delay values for each of the plurality of transmit antennas, and Applying the plurality of cyclic delay values to the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols, respectively. Containing more Signal transmission method. The method of claim 10, And performing frequency-space coding on the plurality of broadcast channel symbols spaced apart from the plurality of sync channel symbols.

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