CN102571255B - Resource mapping and code division multiplexing method and device - Google Patents

Abstract

The invention discloses a resource mapping and code division multiplexing method and device and belongs to the field of communication. The resource mapping method comprises the following steps: selecting one mapping scheme from at least two mapping schemes; staggering a pilot frequency sign with the highest transmitting power corresponding to the selected mapping scheme from a pilot frequency sign with the highest transmitting power corresponding to the mapping scheme selected by at least one adjacent cell in the aspects of frequency and/or time; and performing resource mapping according to the selected mapping scheme. According to the method provided by the invention, one mapping scheme is selected from at least two mapping schemes by each cell, so that the resource mapping is realized and the interference to the pilot frequency sign of a cell boundary user is efficiently reduced. The vector exchange is performed by utilizing an orthogonal matrix, a plurality of different codon sequences are obtained and the codon design is realized, so that the unbalancing problem of the output power of the pilot frequency sign is efficiently solved.

Description

Resource mapping, code division multiplexing method and device

Technical field

The present invention relates to the communications field, particularly a kind of resource mapping, code division multiplexing method and device.

Background technology

In LTE (Long Term Evolut ion, Long Term Evolution) technology, transmitting terminal offers receiving terminal frequency pilot sign, and receiving terminal subscriber equipment can obtain the needed channel estimation value of user data demodulation according to the frequency pilot sign receiving.And in order to guarantee the transmission of frequency pilot sign, need to carry out resource mapping, to determine the corresponding relation between the space level number, frequency pilot sign place subcarrier of transmitted pilot symbol and code word that frequency pilot sign is used.And for the code word in resource mapping, can have multiple design.

Prior art is when realizing resource mapping, and each community adopts identical mapping scheme, and prior art, when carrying out code division multiplexing, adopts same codeword sequence on each frequency pilot sign place subcarrier.

For resource mapping, because each community adopts identical mapping scheme, the frequency pilot sign that causes cell boundary users is subject to compared with strong jamming; And when carrying out code word design, owing to adopting same code word on each frequency pilot sign place subcarrier, there is the power output imbalance problem of frequency pilot sign.

Summary of the invention

The interference being subject in order to reduce the frequency pilot sign of cell boundary users, improves the power output imbalance problem of frequency pilot sign, and the embodiment of the present invention provides a kind of resource mapping, code division multiplexing method and device.Described technical scheme comprises following aspect:

1, a method for mapping resource, comprising:

In at least two kinds of default mapping schemes, select a kind of mapping scheme, described selecteed mapping scheme is corresponding has that the frequency pilot sign of strong transmitting power and the mapping scheme of at least one neighbor cell selection are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time;

According to the mapping scheme of selecting, carry out resource mapping;

Wherein, the code word that the space level number that mapping scheme is transmitted pilot symbol, frequency pilot sign adopt and the corresponding relation between the subcarrier of frequency pilot sign place.

2, according to the method described in aspect 1, at least two kinds of default mapping schemes, select a kind of mapping scheme, comprising:

According to cell ID, at least two kinds of default mapping schemes, select a kind of mapping scheme.

3, according to the method described in aspect 1 or 2, the corresponding frequency division multiplexing of mapping scheme or time-multiplexed frequency pilot sign adopt identical scrambler sequence, and/or adopt different code division multiplexing codeword sequences.

4, a resource mapping apparatus, comprising:

Memory module, at least two kinds of mapping schemes of storage, the code word that the space level number that described mapping scheme is transmitted pilot symbol, frequency pilot sign adopt and the corresponding relation between the subcarrier of frequency pilot sign place;

Select module, for selecting a kind of mapping scheme at least two kinds of mapping schemes of described memory module storage, selecteed mapping scheme is corresponding has that the frequency pilot sign of strong transmitting power and the mapping scheme of at least one neighbor cell selection are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time;

Mapping block, carries out resource mapping for the mapping scheme of selecting according to described selection module;

Wherein, the code word that the space level number that mapping scheme is transmitted pilot symbol, frequency pilot sign adopt and the corresponding relation between the subcarrier of frequency pilot sign place.

5, according to the device described in aspect 4, select module, specifically for according to cell ID, at least two kinds of mapping schemes of memory module storage, select a kind of mapping scheme.

6, a code division multiplexing method, comprising:

Selected orthogonal matrix is carried out to vector exchange, obtain a plurality of different codeword sequences;

Determine the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier;

On described each pilot sub-carrier, the frequency pilot sign of each space layer is carried out multiplexing according to codeword sequence corresponding to each pilot sub-carrier.

7, according to the method described in aspect 6, selected orthogonal matrix is carried out to vector exchange, obtain a plurality of different codeword sequences and comprise:

For the orthogonal matrix W of any 4 dimensions, establish A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4);

Wherein, W (:, m) representing that the m of orthogonal matrix W is listed as corresponding column vector, m is 1 to 4, orthogonal matrix W is carried out to column vector exchange, obtains 4 kinds of different codeword sequences, respectively:

W1＝[A，B，C，D]；

W2＝[B，A，D，C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

Correspondingly, determine the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier, specifically comprise:

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively; Wherein, described n is greater than zero positive integer.

8, according to the method described in aspect 6, selected orthogonal matrix is carried out to vector exchange, obtain a plurality of different codeword sequences, comprising:

For the orthogonal matrix W of any 4 dimensions, establish A`=W` (1 :), B`=W` (2 :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) represents the capable corresponding row vector of m of orthogonal matrix w, and m is 1 to 4, orthogonal matrix W is carried out to row vector exchange, obtains 4 kinds of different codeword sequences, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Correspondingly, determine the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier, specifically comprise:

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively; Wherein, described n is greater than zero positive integer.

9, a code word design apparatus, comprising:

Acquisition module, carries out vector exchange for the orthogonal matrix to selected, obtains a plurality of different codeword sequences;

Determination module, a plurality of different codeword sequence obtaining for definite described acquisition module and the corresponding relation of each pilot sub-carrier;

Multiplexing module, at described each pilot sub-carrier, carries out multiplexing by the frequency pilot sign of each space layer according to codeword sequence corresponding to described each pilot sub-carrier.

10,, according to the device described in aspect 9, acquisition module, specifically for the orthogonal matrix W for any 4 dimensions, establishes A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4);

Wherein, W (:, m) representing that the m of orthogonal matrix W is listed as corresponding column vector, m is 1 to 4, orthogonal matrix W is carried out to column vector exchange, obtains 4 kinds of different codeword sequences, respectively:

W1＝[A，B，C，D]；

W2＝[B，A，D，C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

Correspondingly, described determination module, specifically for

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively; Wherein, described n is greater than zero positive integer.

11,, according to the device described in aspect 9, acquisition module, specifically for the orthogonal matrix W for any 4 dimensions, establishes A`=W` (1 :), B`=W` (2 :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) represents the capable corresponding row vector of m of orthogonal matrix w, and m is 1 to 4, orthogonal matrix W is carried out to row vector exchange, obtains 4 kinds of different codeword sequences, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Correspondingly, described determination module, specifically for

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively; Wherein, described n is greater than zero positive integer.

The beneficial effect of the technical scheme that the embodiment of the present invention provides is:

By each community, at least two kinds of mapping schemes, select a kind of mapping scheme, realize resource mapping, because selecteed mapping scheme is corresponding, have that the frequency pilot sign of the strongest transmitting power and mapping scheme that at least one neighbor cell is selected are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time, can effectively reduce the interference that the pilot signal of cell boundary users is subject to; In addition, by the orthogonal matrix to selected, carry out vector exchange, obtain a plurality of different codeword sequences, and determine the corresponding relation between each pilot sub-carrier and a plurality of different codeword sequences, can effectively improve the power output imbalance problem of frequency pilot sign.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme in the embodiment of the present invention, below the accompanying drawing of required use during embodiment is described is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the method for mapping resource flow chart that the embodiment of the present invention one provides;

Fig. 2 is the structural representation of the time/frequency source block that provides of the embodiment of the present invention two;

Fig. 3 is the method for mapping resource flow chart that the embodiment of the present invention two provides;

Fig. 4 is the structural representation of the resource mapping apparatus that provides of the embodiment of the present invention three;

Fig. 5 is the code division multiplexing method flow chart that the embodiment of the present invention four provides;

Fig. 6 is the code division multiplexing schematic diagram that the embodiment of the present invention five provides;

Fig. 7 is the code division multiplexing method flow chart that the embodiment of the present invention five provides;

Fig. 8 is the structural representation of the code division multiplexing device that provides of the embodiment of the present invention six.

Embodiment

For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with accompanying drawing, embodiment of the present invention is described further in detail.

Embodiment mono-

Referring to Fig. 1, the present embodiment provides a kind of method for mapping resource, and the method flow process is specific as follows:

101: at least two kinds of default mapping schemes, select a kind of mapping scheme, selecteed mapping scheme is corresponding has that the frequency pilot sign of strong transmitting power and the mapping scheme of at least one neighbor cell selection are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time;

102: according to the mapping scheme of selecting, carry out resource mapping.

The method that the present embodiment provides, by each community, at least two kinds of default mapping schemes, select a kind of mapping scheme, realize resource mapping, because selecteed mapping scheme is corresponding, have that the frequency pilot sign of the strongest transmitting power and mapping scheme that at least one neighbor cell is selected are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time, can effectively reduce the interference that the frequency pilot sign of cell boundary users is subject to.

Embodiment bis-

The present embodiment provides a kind of method for mapping resource, and for convenience of explanation, the present embodiment be take the time/frequency source block shown in Fig. 2 as example, and frequency pilot sign place subcarrier is called to pilot sub-carrier, and the method for mapping resource that the present embodiment is provided describes.

In Fig. 2, a subframe comprises 2 slot (time slot), has 7 OFDM (Orthogonal Frequency Division Multiplexing, OFDM) symbol in each slot; In each slot, total 12x7 RE (Resource Element, resource particle).The pilot resource distribution method that this Resource Block adopts is: in time domain, introduce CDM (Code Division Multiplexing, code division multiplexing), can provide the pilot resources of 4 quadratures, as the first resource particle in Fig. 2; On frequency domain, introduce FDM (Frequency Division Multiplexing, frequency division multiplexing), also can provide the pilot resources of 4 quadratures, as the Secondary resource particle in Fig. 2.For the pilot resources method of salary distribution shown in Fig. 2, prior art is when carrying out resource mapping, and each community adopts identical mapping scheme, and the mapping scheme shown in table 1 below of take is example:

Table 1

Space level number

L1

L2

L3

L4

L5

L6

L7

L8

The code word of the one RE

C1

C2

C3

C4

The code word of the 2nd RE

C1

C2

C3

C4

For example, according to the mapping scheme shown in table 1: when space is always transmitted number of plies RANK and is 3, according to the mapping relations shown in above-mentioned table 1, will have 2 space layer and transmit on a RE, and have 1 space layer to transmit on the 2nd RE.If the through-put power of each space layer is equal, and is 1/3 of data RE average power:

The transmitting power of the dedicated pilot resource on the one RE is: (P/3+P/3) * beta=beta*P*2/3;

The transmitting power of the dedicated pilot resource on the 2nd RE is: (P/3) * beta=beta*P/3;

Wherein, beta represents the power adjusting factor of pilot tone, and P represents the average power of data RE.Now, the transmitting power of the upper dedicated pilot resource of a RE is 2 times of transmitting power of the upper dedicated pilot resource of the 2nd RE.

It should be noted that: how the power adjusting factor of pilot tone is set, and is prior art, and the present embodiment is not done concrete restriction.The present embodiment during only with RANK > 2, arranges the power adjusting factor beta=2 of pilot tone, otherwise beta=1 is example, describes.

Further, for the boundary user of neighbor cell, because SINR (Signal to Interference plus Noise Ratio, Signal to Interference plus Noise Ratio) is lower, conventionally can adopt space to transmit the transmission means of total number of plies RANK=1 or 2.If adopt the mapping scheme shown in above-mentioned table 1, this user can take the resource transmission dedicated pilot of a RE.

If establish community 1 and the mapping scheme shown in above-mentioned table 1 is all selected in neighbor cell 2, for the boundary user of community 1, generally adopt the transmission plan of Rank=1 or 2, the interference power from community 2 that frequency pilot sign is subject to is as shown in table 2 below:

Table 2

In table 2, P represents the average power of data RE, in the time of the RANK of community 2 > 2, the power adjusting factor beta=2 of pilot tone is set, otherwise beta=1.When space is transmitted total number of plies (RANK) and is 1,2,3,5 and 7, on a RE, will transmit the more space number of plies so, namely take more power resource, and the corresponding resource of adjacent cell is produced to larger interference.In analysis below, it is more that the present embodiment will take power resource, and the frequency pilot sign that the corresponding resource of adjacent cell produces larger interference is called and has the frequency pilot sign of strong transmitting power, the pilot sub-carrier at such frequency pilot sign place is called and has the pilot sub-carrier of strong transmitting power.

The interference being subject in order to reduce the frequency pilot sign of cell boundary users, the present embodiment provides a kind of method for mapping resource, referring to Fig. 3, take that to preset two kinds of mapping schemes be example, and the method flow process is specific as follows:

301: in two kinds of default mapping schemes, select a kind of mapping scheme, this selecteed mapping scheme is corresponding has that the frequency pilot sign of strong transmitting power and the mapping scheme of at least one neighbor cell selection are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time;

Wherein, the code word that the space level number that mapping scheme is transmitted pilot symbol, frequency pilot sign adopt and the corresponding relation between the subcarrier of frequency pilot sign place.Still take the Resource Block shown in Fig. 2 as example, can establish mapping scheme A as shown in table 3 below and the mapping scheme B shown in table 4:

Table 3

Space level number

L1

L2

L3

L4

L5

L6

L7

L8

The code word of the one RE

C1

C2

C3

C4

The code word of the 2nd RE

C1

C2

C3

C4

Table 4

Space level number

L1

L2

L3

L4

L5

L6

L7

L8

The code word of the one RE

C1

C2

C3

C4

The code word of the 2nd RE

C1

C2

C3

C4

Particularly, while selecting a kind of mapping scheme in two kinds of default mapping schemes, each community can be selected according to Cell ID (cell ID), for example:

If cell ID mod is 2=0, the mapping scheme A shown in option table 3;

If cell ID mod is 2=1, the mapping scheme B shown in option table 4.

If mapping scheme A is selected in community 1, and mapping scheme B is selected in neighbor cell 2.

302: according to the mapping scheme of selecting, carry out resource mapping.

For this step, after carrying out resource mapping,, in pilot symbol transmission process, for the boundary user of community 1, generally adopt the transmission plan of Rank=1 or 2, the interference power from community 2 being subject to is as shown in table 5 below:

Table 5

As shown in table 5, P represents the average power of data RE, in the time of the RANK of community 2 > 2, the power adjusting factor beta=2 of pilot tone is set, otherwise beta=1.As can be seen from Table 5: the mapping scheme that adopts the present embodiment to provide, on the frequency pilot sign of community 1 boundary user, can effectively reduce from the Pilot Interference power of neighbor cell 2.

Further, in the Resource Block shown in Fig. 2, the code word on the code word on a RE and the 2nd RE can be different.The frequency pilot sign that is frequency division multiplexing adopts different codeword sequences, and for example, the mapping scheme shown in table 6 below of take is example, and code word Cm (m=1-4) and Dm (m=1-4) can be different.

Table 6

Space level number

L1

L2

L3

L4

L5

L6

L7

L8

The code word of the one RE

C1

C2

C3

C4

The code word of the 2nd RE

D1

D2

D3

D4

If can use following code word on the RE of community 1:

[1，1，1，1；

1，-1，1，-1；

1，1，-1，-1；

1，-1，-1，1]

And on the 2nd RE, can use the difference of above-mentioned code word to be shifted, for example:

[1，1，1，1；

-1，1，-1，1；

-1，1，1，-1；

1，1，-1，-1]

The benefit of doing is like this: when adopting cell-specific scrambler, if the upper scrambler adopting of a RE and the identical scrambler of the upper employing of the 2nd RE, the frequency pilot sign that is frequency division multiplexing adopts identical scrambler, the intersymbol interference from adjacent cell being subject on upper and the 2nd RE of a RE is different, can improve detection performance like this.

Further, the code word that the frequency pilot sign of neighbor cell is used can be also different, and the present embodiment is not done concrete restriction to this.

The method that the present embodiment provides, by each community, at least two kinds of mapping schemes, select a kind of mapping scheme, realize resource mapping, because selecteed mapping scheme is corresponding, have that the frequency pilot sign of the strongest transmitting power and mapping scheme that at least one neighbor cell is selected are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time, can effectively reduce the interference that the frequency pilot sign of cell boundary users is subject to; In addition, due to the method that the present embodiment provides, also support frequency division multiplexing or time-multiplexed frequency pilot sign to adopt identical scrambler sequence, and/or different codeword sequence, therefore, the intersymbol interference that is subject to neighbor cell in pilot tone is different, and then can improve detection performance.

Embodiment tri-

Referring to Fig. 4, the present embodiment provides a kind of resource mapping apparatus, and this device comprises:

Memory module 401, at least two kinds of mapping schemes of storage, the code word that the space level number that mapping scheme is transmitted pilot symbol, frequency pilot sign adopt and the corresponding relation between the subcarrier of frequency pilot sign place;

Select module 402, for selecting a kind of mapping scheme at least two kinds of mapping schemes of memory module 401 storage, selecteed mapping scheme is corresponding has that the frequency pilot sign of strong transmitting power and the mapping scheme of at least one neighbor cell selection are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time;

Mapping block 403, carries out resource mapping for the mapping scheme according to selecting module 402 to select.

Particularly, select module 402, specifically for according to cell ID, at least two kinds of mapping schemes of memory module 402 storages, select a kind of mapping scheme.

Preferably, frequency division multiplexing or time-multiplexed frequency pilot sign adopt identical scrambler sequence, and/or adopt different codeword sequences.

The device that the present embodiment provides, by each community, at least two kinds of mapping schemes, select a kind of mapping scheme, realize resource mapping, because selecteed mapping scheme is corresponding, have that the frequency pilot sign of the strongest transmitting power and mapping scheme that at least one neighbor cell is selected are corresponding to be had the frequency pilot sign of strong transmitting power and mutually stagger in frequency and/or on the time, can effectively reduce the interference that the frequency pilot sign of cell boundary users is subject to; In addition, due to the method that the present embodiment provides, also support frequency division multiplexing or time-multiplexed frequency pilot sign to adopt identical scrambler sequence, and/or different codeword sequence, therefore, the intersymbol interference that is subject to neighbor cell in pilot tone is different, and then can improve detection performance.

Embodiment tetra-

Referring to Fig. 5, the present embodiment provides a kind of code division multiplexing method, and the method flow process is specific as follows:

501: selected orthogonal matrix is carried out to vector exchange, obtain a plurality of different codeword sequences;

502: the corresponding relation of determining a plurality of different codeword sequences and each pilot sub-carrier;

503: on each pilot sub-carrier, the frequency pilot sign of each space layer is carried out multiplexing according to codeword sequence corresponding to each pilot sub-carrier.

The method that the present embodiment provides, by the orthogonal matrix to selected, carry out vector exchange, obtain a plurality of different codeword sequences, and determine the corresponding relation between each pilot sub-carrier and a plurality of different codeword sequences, make each pilot sub-carrier adopt different codeword sequences, can effectively improve the power output imbalance problem of frequency pilot sign.

Embodiment five

The present embodiment provides a kind of code division multiplexing method, and for convenience of explanation, the present embodiment be take the Resource Block shown in Fig. 6 as example, and the method that the present embodiment is provided is elaborated.

In Fig. 6, a subframe comprises 2 slot (time slot), has 7 OFDM symbols in each slot; In each slot, total 12x7 RE.The pilot resource distribution method that this Resource Block adopts is: in time domain, introduce CDM, the pilot resources of 4 quadratures can be provided.Prior art is in design during code word, at subcarrier n1, and n1+5, n1+10 is upper, adopts same CDM code word (C1-C4).

The Walsh matrix of 4x4 of take is example, for example:

C＝[1，1，1，1；

1，-1，1，-1；

1，1，-1，-1；

1，-1，-1，1]

If the first row that C1 is Matrix C, i.e. C1=C (1 :).Similarly, establish C2=C (2 :), C3=C (3 :), C4=C (4 :).

For Fig. 6, for the Main Analysis scene of unbalanced power, consider space, broadband preliminary treatment vector,, for each space layer, on each subcarrier, adopt identical space preliminary treatment vector.Take 8 transmitting antennas as example, and the dedicated pilot symbol of establishing space layer m carries and transmits on code word Cm (m=1-4), and, on any one pilot sub-carrier, the frequency pilot sign matrix of transmitting terminal is:

$\left[\begin{array}{c}{w}_{11}\\ w_{21}\\ .\\ .\\ .\\ w_{81}\end{array}\right]\left[\begin{array}{cccc}{c}_{11}& c_{12}& c_{13}& c_{14}\end{array}\right]s+...+\left[\begin{array}{c}{w}_{14}\\ w_{24}\\ .\\ .\\ .\\ w_{84}\end{array}\right]\left[\begin{array}{cccc}{c}_{41}& c_{42}& c_{43}& c_{44}\end{array}\right]s$

Wherein, w _ijbe the weight coefficient of j (j=1-4) layer transmission on the individual transmitting antenna of i (i=1-8), s is frequency pilot sign, C _ijcode word C _i(i=1-4) the individual symbol of j (j=1-4).

From above formula, can find out, for the frequency pilot sign vector on the individual transmitting antenna of i (i=1-8), be:

$\left[\begin{array}{cccc}{p}_{1i}& p_{2i}& p_{3i}& p_{4i}\end{array}\right]=\left(\begin{array}{c}{w}_{i1}\left[\begin{array}{cccc}{c}_{11}& c_{12}& c_{13}& c_{14}\end{array}\right]+\\ w_{i2}\left[\begin{array}{cccc}{c}_{21}& c_{22}& c_{23}& c_{24}\end{array}\right]+\\ w_{i3}\left[\begin{array}{cccc}{c}_{31}& c_{32}& c_{33}& c_{34}\end{array}\right]+\\ w_{i4}\left[\begin{array}{cccc}{c}_{41}& c_{42}& c_{43}& c_{44}\end{array}\right]+\end{array}\right)s$

Wherein, symbol P _ki, (k=1-4) on the OFDM of i transmitting antenna symbol 6,7,13 and 14, transmit respectively.

For different i and j, consider space preliminary treatment vector coefficient w _ijgenerally different, in conjunction with the orthogonality of code word matrix C, for different i and j, C (:, i) be not equal to C (:, therefore j), can release: frequency pilot sign P _ki, (k=1-4) be generally 4 different numerical value.That is to say: on any one pilot sub-carrier, the frequency pilot sign sending on OFDM symbol 6,7,13 and 14 is different.

Further, consider on all pilot sub-carriers and adopt the same same pilot tone code word of space preliminary treatment vector sum, now, on each pilot tone OFDM symbol, the power sum of pilot tone RE respectively:

P ₆＝∑(|p _1i| ²)；

P ₇＝∑(|P _2i| ²)；

P ₁₃＝∑(|P _3i| ²)；

P ₁₄＝∑(|P _4i| ²)；

Wherein, P _mbe illustrated in pilot tone OFDM symbol m (, m=6,7,13,14) here upper, the power sum of all pilot tone RE.According to above-mentioned analysis, can know, generally:

P ₆≠P ₇≠P ₁₃≠P ₁₄

That is to say: on each pilot tone OFDM symbol, have the power output imbalance problem of pilot tone.

In order to solve the power output imbalance problem of pilot tone, the present embodiment provides a kind of code word method for designing, and referring to Fig. 7, the method flow that the present embodiment provides is specific as follows:

701: 4 selected orthogonal dimension matrixes are carried out to column vector exchange, obtain 4 different codeword sequences;

Wherein, for convenience of explanation, the 4x4 Walsh matrix of take is example, as:

Orthogonal matrix W=[1,1,1,1;

1，-1，1，-1；

1，1，-1，-1；

1，-1，-1，1]

If A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4).

Quadrature matrix W is carried out to column vector exchange, obtain four kinds of transformation matrixs of orthogonal matrix W, respectively:

W1＝[A，B，C，D ]；

W2＝[B，A，D，C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

702: the corresponding relation of determining 4 different codeword sequences and each pilot sub-carrier;

Particularly, 4 different codeword sequences that obtain according to above-mentioned steps 701, these 4 different codeword sequences and each pilot sub-carrier can adopt following corresponding relation:

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively.

Wherein: at pilot sub-carrier n1, n2 ... upper, the frequency pilot sign of these space layer relies on CDM code to carry out multiplexing.

703: on each pilot sub-carrier, the frequency pilot sign of each space layer is carried out multiplexing according to codeword sequence corresponding to each pilot sub-carrier.

The code division multiplexing method providing for the present embodiment, when solving the power output imbalance problem of frequency pilot sign, make a concrete analysis of as follows:

Consider broadband, space preliminary treatment vector, still take 8 transmitting antennas as example.As shown in Figure 6, on subcarrier n1, the dedicated pilot symbol of establishing space layer m (m=1-4) carries and transmits in code word W 1 (m :), and on subcarrier n1, the frequency pilot sign matrix of transmitting terminal is:

$\left[\begin{array}{c}{w}_{11}\\ w_{21}\\ .\\ .\\ .\\ w_{81}\end{array}\right]\left[\begin{array}{cccc}W1\left(\mathrm{1,1}\right)& W1\left(\mathrm{1,2}\right)& W1\left(\mathrm{1,3}\right)& W1\left(\mathrm{1,4}\right)\end{array}\right]s+...+\left[\begin{array}{c}{w}_{14}\\ w_{24}\\ .\\ .\\ .\\ w_{84}\end{array}\right]\left[\begin{array}{cccc}W1\left(\mathrm{4,1}\right)& W1\left(\mathrm{4,2}\right)& W1\left(\mathrm{4,3}\right)& W1\left(\mathrm{4,4}\right)\end{array}\right]s$

W wherein _ijbe the weight coefficient of j (j=1-4) layer transmission on the individual transmitting antenna of i (i=1-8), s is frequency pilot sign.

As can be seen from the above equation, the frequency pilot sign vector on the individual transmitting antenna of i (i=1-8) is:

$\left[\begin{array}{cccc}{p}_{1i}& p_{2i}& p_{3i}& p_{4i}\end{array}\right]=\left(\begin{array}{c}{w}_{i1}\left[\begin{array}{cccc}W1\left(\mathrm{1,1}\right)& W1\left(\mathrm{1,2}\right)& W1\left(\mathrm{1,3}\right)& W\left(\mathrm{1,4}\right)\end{array}\right]+\\ w_{i2}\left[\begin{array}{cccc}W1\left(\mathrm{2,1}\right)& W1\left(\mathrm{2,2}\right)& W1\left(\mathrm{2,3}\right)& W1\left(\mathrm{2,4}\right)\end{array}\right]+\\ w_{i3}\left[\begin{array}{cccc}W1\left(\mathrm{3,1}\right)& W1\left(\mathrm{3,2}\right)& W1\left(\mathrm{3,3}\right)& W1\left(\mathrm{3,4}\right)\end{array}\right]+\\ w_{i4}\left[\begin{array}{cccc}W1\left(\mathrm{4,1}\right)& W1\left(\mathrm{4,2}\right)& W1\left(\mathrm{4,3}\right)& W1\left(\mathrm{4,4}\right)\end{array}\right]+\end{array}\right)s$

Wherein, symbol P _ki, (k=1-4) on the pilot tone OFDM of i transmitting antenna symbol 6,7,13 and 14, transmit respectively.

According to the corresponding relation of W2 and W1, can release on pilot sub-carrier n2, the frequency pilot sign vector on the corresponding individual transmitting antenna of i (i=1-8) is: [p _2ip _1ip _4ip _3i].Similarly, can release:

On pilot sub-carrier n3, the frequency pilot sign vector on the corresponding individual transmitting antenna of i (i=1-8) is: [p _3ip _4ip _1ip _2i];

On pilot sub-carrier n4, the frequency pilot sign vector on the corresponding individual transmitting antenna of i (i=1-8) is: [p _4ip _3ip _2ip _1i].

If pilot sub-carrier number is 4 integral multiple, can release: on the individual transmitting antenna of the i of correspondence (i=1-8), at each pilot tone OFDM symbol, OFDM symbol 6,7, on 13 and 14, the power sum on all pilot tone RE equates, that is:

P ₆＝P ₇＝P ₁₃＝P ₁₄＝∑(|p _1i| ²+|p _2i| ²+|p _3i| ²+|p _4i| ²)

Wherein, P _mbe illustrated in pilot tone OFDM symbol m (, m=6,7,13,14) here upper, the power sum of all pilot tone RE.Now, because the power output of each pilot tone OFDM symbol all equates, so just solved the unbalanced problem of pilot tone power output.

Further, if pilot sub-carrier number is not 4 integral multiple, at each pilot tone OFDM symbol, OFDM symbol 6,7, and on 13,14, the power sum of pilot tone RE is also more or less the same, and the power output imbalance problem of pilot tone also will be very significantly improved.

For example: if pilot sub-carrier number is 5, can release: on each pilot tone OFDM symbol 6,7,13,14, the power sum of pilot tone RE respectively:

P ₆＝(|p _1i| ²+|p _2i| ²+|p _3i| ²+|p _4i| ²)+|p _1i| ²；

P ₇＝(|p _1i| ²+|p _2i| ²+|p _3i| ²+|p _4i| ²)+|p _2i| ²；

P ₁₃＝(|p _1i| ²+|p _2i| ²+|p _3i| ²+|p _4i| ²)+|p _3i| ²；

P ₁₄＝(|p _1i| ²+|p _2i| ²+|p _3i| ²+|p _4i| ²)+|p _4i| ²；

From above formula, can find out: on each pilot tone OFDM symbol 6,7,13,14, the power sum of pilot tone RE only differs one, therefore, can improve the unbalanced power problem of pilot tone output.

Alternatively, except the orthogonal matrix to selected carries out column vector exchange, obtain a plurality of different codeword sequences, can also carry out row vector exchange to selected orthogonal matrix, obtain a plurality of different codeword sequences.The present embodiment does not specifically limit the vectorial exchanging form of orthogonal matrix.Below, the 4 orthogonal dimension matrix W of still take are example, and orthogonal matrix is carried out to row vector exchange, obtaining 4 different codeword sequences describes,, for the orthogonal matrix W of any 4 dimensions, establish A`=W` (1 :), B`=W` (2, :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) (m=1..4) represents the capable corresponding row vector of m of W matrix; Quadrature matrix W is carried out to row vector exchange, four kinds of transformation matrixs that obtain, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Correspondingly, the corresponding relation of each pilot sub-carrier codeword sequence different from 4 is as follows:

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively.

The method that the present embodiment provides, by the orthogonal matrix to selected, carry out vector exchange, obtain a plurality of different codeword sequences, and determine the corresponding relation between each pilot sub-carrier and a plurality of different codeword sequences, make each pilot sub-carrier adopt different codeword sequences, thereby can effectively improve the power output imbalance problem of frequency pilot sign.

Embodiment six

Referring to Fig. 8, the present embodiment provides a kind of code division multiplexing device, and this device comprises:

Acquisition module 801, carries out vector exchange for the orthogonal matrix to selected, obtains a plurality of different codeword sequences;

Determination module 802, a plurality of different codeword sequence obtaining for definite acquisition module and the corresponding relation of each pilot sub-carrier;

Multiplexing module 803, at each pilot sub-carrier, carries out multiplexing by the frequency pilot sign of each space layer according to codeword sequence corresponding to each pilot sub-carrier.

Wherein, acquisition module 801, specifically for the orthogonal matrix W for any 4 dimensions,

If A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4);

Wherein, W (:, m) representing that the m of orthogonal matrix W is listed as corresponding column vector, m is 1 to 4, orthogonal matrix W is carried out to column vector exchange, obtains 4 kinds of different codeword sequences, respectively:

W1＝[A，B，C，D]；

W2＝[B，A，D，C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

Correspondingly, determination module 802, specifically for

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively.

Alternatively, acquisition module 801, specifically for the orthogonal matrix W for any 4 dimensions, establishes A`=W` (1 :), B`=W` (2 :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) (m=1..4) represents the capable corresponding row vector of m of orthogonal matrix w, and m is 1 to 4, orthogonal matrix W is carried out to row vector exchange, obtains 4 kinds of different codeword sequences, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Correspondingly, determination module 802, specifically for

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively.

In sum, the device that the present embodiment provides, by the orthogonal matrix to selected, carry out vector exchange, obtain a plurality of different codeword sequences, and determine the corresponding relation between each pilot sub-carrier and a plurality of different codeword sequences, make each pilot sub-carrier adopt different codeword sequences, thereby can effectively improve the unbalanced power problem causing due to pilot tone.

The invention described above embodiment sequence number, just to describing, does not represent the quality of embodiment.

All or part of step in the embodiment of the present invention, can utilize software to realize, and corresponding software program can be stored in the storage medium can read, as CD or hard disk etc.

The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (6)

1. a code division multiplexing method, is characterized in that, described method comprises:

Transmitting terminal carries out vector exchange to selected orthogonal matrix, obtains a plurality of different codeword sequences;

Described transmitting terminal is determined the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier;

Described transmitting terminal, on described each pilot sub-carrier, carries out multiplexing by the frequency pilot sign of each space layer according to codeword sequence corresponding to each pilot sub-carrier;

Receiving terminal subscriber equipment receives the frequency pilot sign that transmitting terminal sends;

Described receiving terminal subscriber equipment obtains the needed channel estimation value of user data demodulation according to described frequency pilot sign.

2. method according to claim 1, is characterized in that, described selected orthogonal matrix is carried out to vector exchange, obtains a plurality of different codeword sequences, specifically comprises:

For the orthogonal matrix W of any 4 dimensions, establish A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4);

Wherein, W (:, m) representing that the m of orthogonal matrix W is listed as corresponding column vector, m is 1 to 4, orthogonal matrix W is carried out to column vector exchange, obtains 4 kinds of different codeword sequences, respectively:

W1＝[A,B,C,D]；

W2＝[B,A,D,C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

Correspondingly, determine the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier, specifically comprise:

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively; Wherein, described n is greater than zero positive integer.

3. method according to claim 1, is characterized in that, described selected orthogonal matrix is carried out to vector exchange, obtains a plurality of different codeword sequences, specifically comprises:

For the orthogonal matrix W of any 4 dimensions, establish A`=W` (1 :), B`=W` (2 :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) represents the capable corresponding row vector of m of orthogonal matrix w, and m is 1 to 4, orthogonal matrix W is carried out to row vector exchange, obtains 4 kinds of different codeword sequences, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Correspondingly, determine the corresponding relation of described a plurality of different codeword sequences and each pilot sub-carrier, specifically comprise:

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively; Wherein, described n is greater than zero positive integer.

4. a code-division multiplexing system, is characterized in that, described system comprises:

Transmitting terminal, carries out vector exchange for the orthogonal matrix to selected, obtains a plurality of different codeword sequences; A plurality of different codeword sequence obtaining described in determining and the corresponding relation of each pilot sub-carrier; With on described each pilot sub-carrier, the frequency pilot sign of each space layer is carried out multiplexing according to codeword sequence corresponding to described each pilot sub-carrier;

Receiving terminal subscriber equipment, the frequency pilot sign sending for receiving transmitting terminal; With according to described frequency pilot sign, obtain the needed channel estimation value of user data demodulation.

5. system according to claim 4, is characterized in that, described transmitting terminal, specifically for the orthogonal matrix W for any 4 dimensions, is established A=W (:, 1), B=W (:, 2), C=W (:, 3), D=W (:, 4);

Wherein, W (:, m) representing that the m of orthogonal matrix W is listed as corresponding column vector, m is 1 to 4, orthogonal matrix W is carried out to column vector exchange, obtains 4 kinds of different codeword sequences, respectively:

W1＝[A,B,C,D]；

W2＝[B,A,D,C]；

W3=[C, D, A, B], or, [C, D, B, A];

W4=[D, C, B, A], or, [D, C, A, B];

Wherein,

For pilot sub-carrier n1, adopt codeword sequence W1;

For pilot sub-carrier n2, adopt codeword sequence W2;

For pilot sub-carrier n3, adopt codeword sequence W3;

For pilot sub-carrier n4, adopt codeword sequence W4;

For pilot sub-carrier n5, adopt codeword sequence W1;

For pilot sub-carrier n6, adopt codeword sequence W2;

And repeat down successively; Wherein, described n is greater than zero positive integer.

6. system according to claim 4, is characterized in that, described transmitting terminal, specifically for the orthogonal matrix W for any 4 dimensions, is established A`=W` (1 :), B`=W` (2 :), C`=W` (3 :), D`=W` (4 :);

Wherein, W` (m :) represents the capable corresponding row vector of m of orthogonal matrix w, and m is 1 to 4, orthogonal matrix W is carried out to row vector exchange, obtains 4 kinds of different codeword sequences, respectively:

${W_1}^{`}=\left[\begin{array}{c}{A}^{`}\\ B^{`}\\ C^{`}\\ D^{`}\end{array}\right];$ ${W_2}^{`}=\left[\begin{array}{c}{B}^{`}\\ A^{`}\\ D^{`}\\ C^{`}\end{array}\right];$ ${W_3}^{`}=\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ A^{`}\\ B^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{C}^{`}\\ D^{`}\\ B^{`}\\ A^{`}\end{array}\right];$ ${W_4}^{`}=\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ B^{`}\\ A^{`}\end{array}\right],$ Or, $\left[\begin{array}{c}{D}^{`}\\ C^{`}\\ A^{`}\\ B^{`}\end{array}\right];$

Wherein,

For pilot sub-carrier n1, adopt codeword sequence W1`;

For pilot sub-carrier n2, adopt codeword sequence W2`;

For pilot sub-carrier n3, adopt codeword sequence W3`;

For pilot sub-carrier n4, adopt codeword sequence W4`;

For pilot sub-carrier n5, adopt codeword sequence W1`;

For pilot sub-carrier n6, adopt codeword sequence W2`;

And repeat down successively; Wherein, described n is greater than zero positive integer.