CN105391545A - Method of generating pseudo-random sequence in LTE system - Google Patents

Abstract

The invention discloses a method of generating a pseudo-random sequence in an LTE system. The method comprises the steps of obtaining an initial sequence of a first pseudo-random sequence according to communication information of the LTE system; obtaining an initial sequence of a second pseudo-random sequence; performing phase mask sequence operation of the first pseudo-random sequence to obtain a self-scrambling sequence; performing phase mask sequence operation of the second pseudo-random sequence to obtain a self-scrambling sequence; and performing XOR operation of the two self-scrambling sequences to finally obtain a scrambling sequence for scrambling or descrambling. The invention can effectively improve the generation time of a scramble code without increasing the computational complexity, and the overall performance of a communication system is improved.

Description

A kind of generation method of pseudo random sequence in LTE system

Technical field

The present invention relates to a kind of method using scrambler sequence to carry out scrambling or descrambling, belong to wide-band mobile communication technical field.

Background technology

Along with the development of modern technologies, wide-band mobile communication system is widely used, and people can communicate whenever and wherever possible.But if be not encrypted operation to data in communication system, user data is easy to be stolen by third party, and therefore cryptographic operation is most important.A kind of cryptographic operation of current comparative maturity carries out scrambling by scrambler sequence to data at transmitting terminal exactly, uses identical scrambler sequence to carry out descrambling to data at receiving terminal.So just can effectively prevent data from being obtained by third party.

The time that the generation method of usual scrambler sequence expends is long, and this does not obviously meet the requirement of high-speed communication.For this reason, the present invention proposes a kind of new pseudo random sequence generation method, while not increasing computation complexity, can significantly shorten the rise time of scrambler sequence.

Summary of the invention

Goal of the invention: in order to overcome the deficiencies in the prior art, the invention provides the generation method of pseudo random sequence in a kind of LTE system, solves the generation long problem consuming time of scrambler in a communications system.

Technical scheme: for achieving the above object, the technical solution used in the present invention is:

A generation method for pseudo random sequence in LTE system, obtains the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence according to the communication information; Carrying out the operation of phase place mask code sequence to the first pseudo random sequence obtains from scramble sequence; Carrying out the operation of phase place mask code sequence to the second pseudo random sequence obtains from scramble sequence; Carry out xor operation to two groups from scramble sequence, finally obtain the scrambler sequence for scrambling or descrambling, specifically comprise the following steps:

Step 1, obtains the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence according to the communication information of LTE system;

Step 2, the mask code sequence of first, second pseudo random sequence is generated respectively according to the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence, wherein, the mask code sequence of the first pseudo random sequence is a fixing sequence relevant to phase place, the sequence of fixing that the mask code sequence of the second pseudo random sequence is relevant with sequence initial value with phase place;

Step 3, the mask code sequence of the initiation sequence of the first pseudo random sequence that step 1 obtains and the first pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the first pseudo random sequence from scramble sequence; The mask code sequence of the initiation sequence of the second pseudo random sequence that step 1 obtains and the second pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the second pseudo random sequence from scramble sequence;

Step 4, what step 3 obtained the first pseudo random sequence carries out xor operation from scramble sequence and the second pseudo random sequence from scramble sequence, obtains the scrambler sequence for scrambling or descrambling.

Preferred: the method producing the mask code sequence of the first pseudo random sequence in described step 2:

Step 211, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the first pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described first pseudo random sequence is x ₁(0)=1, x ₂(n)=0; N=1...30, N _cvalue be 1600;

Step 212, the initial value of the first pseudo random sequence obtained according to step 1 set up the first pseudo random sequence from scramble sequence generator polynomial:

x ₁(n+31)＝(x ₁(n)+x ₁(n+3))mod2；

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 213, according to the initial value of the first pseudo random sequence, the figure place N of scrambler sequence generation that step 1 obtains _cvalue and the mask code sequence M obtaining the first pseudo random sequence from scramble sequence generator polynomial of the first pseudo random sequence that determines of step 212 ₁; Wherein:

M ₁＝[0101111001001000010110000100000]。

Preferred: in described step 3 first pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_1(1600+n)=\left(sum\right(\[x_1\left(0+n\right)x_1\left(1+n\right)x_1\left(2+n\right)\mathrm{......}{x}_1\left(30+n\right)\]*M_1^T\left)\right)\mathrm{mod}2$

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and mod is mod, M ₁be the mask code sequence of the first pseudo random sequence, M ₁=[0101111001001000010110000100000].

Preferred: the method producing the mask code sequence of the second pseudo random sequence in described step 2:

Step 221, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the second pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described second pseudo random sequence is x ₂(0)=1, x ₂(n)=0; N=1...30, the figure place N that scrambler sequence produces _cvalue be 1600;

Step 222, the initial value of the second pseudo random sequence obtained according to step 1 set up the second pseudo random sequence from scramble sequence generator polynomial:

x ₂(n+31)＝(x ₂(n)+x ₂(n+1)+x ₂(n+2)+x ₂(n+3))mod2；

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 223, defines 31 phase sequences, is respectively:

α ₀(0)＝1,α ₀(n)＝0；n＝1...30

α ₁(1)＝1,α ₁(n)＝0；n＝0,2...30

α ₂(2)＝1,α ₂(n)＝0；n＝0...1,3...30

……

α ₃₀(30)＝1,α ₃₀(n)＝0；n＝0...29；

These 31 phase sequences form one group of base, represent any one sequence of 31;

Step 224, according to step 222 set up the second pseudo random sequence set up mask code sequence generator polynomial from scramble sequence generator polynomial:

x ₂(n+1600)

＝sum[x ₂(n+1)x ₂(n+2)x ₂(n+3)x ₂(n+8)x ₂(n+12)x ₂(n+16)x ₂(n+19)x ₂(n+20)x ₂(n+23)]mod2；

31 phase sequences step 223 defined obtain the mask code sequence (M corresponding to 31 phase sequences by mask code sequence generator polynomial successively _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}), and then obtain mask code matrix M ₂:

Step 225, according to the initialization value C of the initiation sequence of the second pseudo random sequence _initwith the mask code matrix M that step 224 obtains ₂=[M _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}] obtain the mask code sequence M of the second pseudo random sequence ₃: $M_3=M_2*C_{init}^T.$

Preferred: in described step 3 second pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_2(1600+n)=\left(sum\right(\[x_2\left(0+n\right)x_2\left(1+n\right)x_2\left(2+n\right)\mathrm{......}{x}_2\left(30+n\right)\]*M_3^T\left)\right)\mathrm{mod}2;$

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.

Preferred: in described step 4, the formula of scrambler sequence is:

c(n)＝(x ₁(n+N _c)+x ₂(n+N _c))mod2

Wherein, c (n) scrambler sequence, x ₁be the first pseudo random sequence, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.

Beneficial effect: the generation method of pseudo random sequence in a kind of LTE system provided by the invention, compared to existing technology, has following beneficial effect:

While not increasing computation complexity, effectively can improve the rise time of scrambler, improve the overall performance of communication system.

Accompanying drawing explanation

The scrambling that Fig. 1 adopts for the embodiment of the present invention or descrambling system structured flowchart.

First pseudo random sequence from scramble sequence generative process in the scrambler sequence that Fig. 2 adopts for the embodiment of the present invention.

Second pseudo random sequence from scramble sequence generative process in the scrambler sequence that Fig. 3 adopts for the embodiment of the present invention.

Mask code sequence M in the second pseudo random sequence that Fig. 4 adopts for the embodiment of the present invention ₃acquisition.

Phase place mask code matrix M in the second pseudo random sequence that Fig. 5 adopts for the embodiment of the present invention ₂acquisition.

Embodiment

Below in conjunction with the drawings and specific embodiments, illustrate the present invention further, these examples should be understood only be not used in for illustration of the present invention and limit the scope of the invention, after having read the present invention, the amendment of those skilled in the art to the various equivalent form of value of the present invention has all fallen within the application's claims limited range.

A generation method for pseudo random sequence in LTE system, as Figure 1-5, obtains the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence according to the communication information; Carrying out the operation of phase place mask code sequence to the first pseudo random sequence obtains from scramble sequence; Carrying out the operation of phase place mask code sequence to the second pseudo random sequence obtains from scramble sequence; Carry out xor operation to two groups from scramble sequence, finally obtain the scrambler sequence for scrambling or descrambling, specifically comprise the following steps:

Step 1, obtains the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence according to the communication information of LTE system.

Step 2, the mask code sequence of first, second pseudo random sequence is generated respectively according to the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence, wherein, the mask code sequence of the first pseudo random sequence is a fixing sequence relevant to phase place, the sequence of fixing that the mask code sequence of the second pseudo random sequence is relevant with sequence initial value with phase place.

Produce the method for the mask code sequence of the first pseudo random sequence:

Step 211, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the first pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described first pseudo random sequence is x ₁(0)=1, x ₂(n)=0; N=1...30, N _cvalue be 1600;

Step 212, the initial value of the first pseudo random sequence obtained according to step 1 set up the first pseudo random sequence from scramble sequence generator polynomial:

x ₁(n+31)＝(x ₁(n)+x ₁(n+3))mod2；

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 213, according to the initial value of the first pseudo random sequence, the figure place N of scrambler sequence generation that step 1 obtains _cvalue and the mask code sequence M obtaining the first pseudo random sequence from scramble sequence generator polynomial of the first pseudo random sequence that determines of step 212 ₁; Wherein:

M ₁＝[0101111001001000010110000100000]。

Produce the method for the mask code sequence of the second pseudo random sequence:

Step 221, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the second pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described second pseudo random sequence is x ₂(0)=1, x ₂(n)=0; N=1...30, the figure place N that scrambler sequence produces _cvalue be 1600;

Step 222, the initial value of the second pseudo random sequence obtained according to step 1 set up the second pseudo random sequence from scramble sequence generator polynomial:

x ₂(n+31)＝(x ₂(n)+x ₂(n+1)+x ₂(n+2)+x ₂(n+3))mod2；

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 223, defines 31 phase sequences, is respectively:

α ₀(0)＝1,α ₀(n)＝0；n＝1...30

α ₁(1)＝1,α ₁(n)＝0；n＝0,2...30

α ₂(2)＝1,α ₂(n)＝0；n＝0...1,3...30

……

α ₃₀(30)＝1,α ₃₀(n)＝0；n＝0...29；

These 31 phase sequences form one group of base, represent any one sequence of 31;

Step 224, according to step 222 set up the second pseudo random sequence set up mask code sequence generator polynomial from scramble sequence generator polynomial:

x ₂(n+1600)

＝sum[x ₂(n+1)x ₂(n+2)x ₂(n+3)x ₂(n+8)x ₂(n+12)x ₂(n+16)x ₂(n+19)x ₂(n+20)x ₂(n+23)]mod2；

31 phase sequences step 223 defined obtain the mask code sequence (M corresponding to 31 phase sequences by mask code sequence generator polynomial successively _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}), and then obtain mask code matrix M ₂:

M ₂＝[M _α0；M _α1；M _α2；...；M _α30]；

Step 225, according to the initialization value C of the initiation sequence of the second pseudo random sequence _initwith the mask code matrix M that step 224 obtains ₂=[M _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}] obtain the mask code sequence M of the second pseudo random sequence ₃: $M_3=M_2*C_{init}^T.$

Step 3, the mask code sequence of the initiation sequence of the first pseudo random sequence that step 1 obtains and the first pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the first pseudo random sequence from scramble sequence; The mask code sequence of the initiation sequence of the second pseudo random sequence that step 1 obtains and the second pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the second pseudo random sequence from scramble sequence.

First pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_1(1600+n)=\left(sum\right(\[x_1\left(0+n\right)x_1\left(1+n\right)x_1\left(2+n\right)\mathrm{......}{x}_1\left(30+n\right)\]*M_1^T\left)\right)\mathrm{mod}2$

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and mod is mod, M ₁be the mask code sequence of the first pseudo random sequence, M ₁=[0101111001001000010110000100000].

Second pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_2(1600+n)=\left(sum\right(\[x_2\left(0+n\right)x_2\left(1+n\right)x_2\left(2+n\right)\mathrm{......}{x}_2\left(30+n\right)\]*M_3^T\left)\right)\mathrm{mod}2;$

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.

Step 4, what step 3 obtained the first pseudo random sequence carries out xor operation from scramble sequence and the second pseudo random sequence from scramble sequence, obtains the scrambler sequence for scrambling or descrambling.

The formula of scrambler sequence is:

c(n)＝(x ₁(n+N _c)+x ₂(n+N _c))mod2

Wherein, c (n) scrambler sequence, x ₁be the first pseudo random sequence, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.

In order to better the present invention is described, present first chance principle of the present invention illustrates as follows:

As shown in Figure 1, scrambling is that transfer sequence and scrambler sequence are carried out xor operation, and the transfer sequence obtained is uncorrelated with original transferring content, serves the effect of protected data.At receiving terminal, use identical scrambler sequence correctly can go out data by descrambling, otherwise the data that descrambling makes mistake.

The formula of scrambler sequence is:

C (n)=(x ₁(n+N _c)+x ₂(n+N _c)) mod2 (formula 1)

Wherein x ₁be the first pseudo random sequence, x ₂be the second pseudo random sequence, these two sequences are Gold sequence, and initial value is 31, and namely n is from 0 to 30.Therefore, c (n) is also a Gold sequence.As shown in Figure 2, for the first pseudo random sequence, its initial value is x ₁(0)=1, x ₂(n)=0; N=1...30.Like this, can by mask code sequence produce the first pseudo random sequence from scramble sequence, specific implementation process is as follows.

First pseudo random sequence from scramble sequence generator polynomial be:

X ₁(n+31)=(x ₁(n)+x ₁(n+3)) mod2 (formula 2)

Can be known by formula 2, from scramble sequence from the 31st, all with above sequence is relevant for each.Know that scrambler sequence is by N according to formula 1 again _cposition produces.N in LTE system _cvalue is 1600.Therefore, from scramble sequence from the 1600th, ordered sequence is only, for generation of scrambler sequence c (n).Obviously, the calculating of 1600 times had both wasted the time and had wasted resource.In order to accelerate computing, can find a mask code sequence, the effect of this mask code sequence makes the initiation sequence of pseudo random sequence by after mask, obtains the 1600th from scramble sequence.Then, as shown in Figure 3, initiation sequence produces from scrambling sequence values by formula 2, the data window biased forwards of 31, obtain new sequence, this sequence is the data of the 1600th by what produce after mask, but for whole from scramble sequence, these data are the 1601st from scramble sequence, namely offset along with the skew of data window from scramble sequence.Because phase difference is constant, thus mask code sequence is remained unchanged.Finally, 1600 and later all from scramble sequence data can be drawn.By calculating, this mask code sequence is:

M ₁=[0101111001001000010110000100000] (formula 3)

Can draw:

$x_1(1600+n)=\left(sum\right(\[x_1\left(0+n\right)x_1\left(1+n\right)x_1\left(2+n\right)\mathrm{......}{x}_1\left(30+n\right)\]*M_1^T\left)\right)\mathrm{mod}2$ (formula 4)

Like this, first carry out biased forwards by formula 2, then calculate 1600 and later from scramble sequence by mask code sequence.

As shown in Figure 4, the maximum difference of the second pseudo random sequence and the first pseudo random sequence is initiation sequence and the C of the second pseudo random sequence _initbe worth relevant, wherein, C _initvalue is the initialization value of the initiation sequence of the second pseudo random sequence, according to 3GPP agreement regulation, and C _initvalue has different definition value at different channels, the second pseudo random sequence from scramble sequence generator polynomial be:

X ₂(n+31)=(x ₂(n)+x ₂(n+1)+x ₂(n+2)+x ₂(n+3)) mod2 (formula 5)

Equally, the second pseudo random sequence from scramble sequence at the 1600th and the generation of scrambler sequence could be used for later.Similar with the method for process first pseudo random sequence, different places is the mask code sequence M calculated ₃with C _initbe worth relevant.Definition initiation sequence is x ₂(0)=1, x ₂(n)=0; N=1...30, makes data window biased forwards by generator polynomial, constantly produces new for scrambling sequence values.

As shown in Figure 5, in order to obtain mask code sequence M ₃, first define 31 phase sequences, be respectively:

α ₀(0)＝1,α ₀(n)＝0；n＝1...30

α ₁(1)＝1,α ₁(n)＝0；n＝0,2...30

α ₂(2)＝1,α ₂(n)＝0；n＝0...1,3...30

……

α ₃₀(30)＝1,α ₃₀(n)＝0；n＝0...29

31 phase sequences form one group of base above, can represent any one sequence of 31.Find out the mask code sequence of each phase sequence, draw phase place mask code matrix M ₂, as follows:

First phase sequence is α ₀(0)=1, α ₀(n)=0; N=1...30, calculating generator polynomial is:

x ₂(n+1600)

=sum [x ₂(n+1) x ₂(n+2) x ₂(n+3) x ₂(n+8) x ₂(n+12) x ₂(n+16) x ₂(n+19) x ₂(n+20) x ₂(n+23)] mod2 (formula 6)

Namely phase sequence α ₀mask code sequence be:

M _α0＝[011100001000100010011001000000]

By that analogy, after calculating the mask code sequence of all phase sequences, obtain mask code matrix M ₂.

Mask code matrix M ₂formula is:

M ₂=[M _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}] (formula 7)

Calculate matrix M ₂value be:

Then, C _initvalue and matrix M ₂make matrix multiplication, obtain mask code sequence:

M ₃=M ₂* Cinit ^t(formula 8)

M ₃the value of every a line represents C _initthe value calculated after being updated to the generator polynomial of this phase place.

Initiation sequence x ₂(0)=1, x ₂(n)=1; N=1...30 and mask code sequence M ₃be multiplied, obtain the numerical value from scramble sequence of the 1600th, then the data window of initiation sequence 31 bit wide calculates new data window sequence by formula 5 biased forwards.

At acquisition first pseudo random sequence and the second pseudo random sequence the 1600th and later after the numerical value of scramble sequence, just scrambler sequence can be calculated according to formula 1.Finally, it should be noted that above mask code sequence is only applicable to N _cthe situation of=1600, works as N _cwhen value is different, mask code sequence also can be different, but method is constant.

In the embodiment that the application provides, should be understood that, disclosed method, not exceeding in the spirit and scope of the application, can realize in other way.Current embodiment is a kind of exemplary example, should as restriction, and given particular content should in no way limit the object of the application.Such as, multiple unit or assembly can in conjunction with or another system can be integrated into, or some features can be ignored, or do not perform

The above is only the preferred embodiment of the present invention; be noted that for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (6)

1. the generation method of pseudo random sequence in LTE system, is characterized in that, comprise the following steps:

Step 1, obtains the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence according to the communication information of LTE system;

Step 2, the mask code sequence of first, second pseudo random sequence is generated respectively according to the initiation sequence of the first pseudo random sequence, the initiation sequence of the second pseudo random sequence, wherein, the mask code sequence of the first pseudo random sequence is a fixing sequence relevant to phase place, the sequence of fixing that the mask code sequence of the second pseudo random sequence is relevant with sequence initial value with phase place;

Step 3, the mask code sequence of the initiation sequence of the first pseudo random sequence that step 1 obtains and the first pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the first pseudo random sequence from scramble sequence; The mask code sequence of the initiation sequence of the second pseudo random sequence that step 1 obtains and the second pseudo random sequence that step 2 generates carries out step-by-step xor operation, obtain the second pseudo random sequence from scramble sequence;

Step 4, what step 3 obtained the first pseudo random sequence carries out xor operation from scramble sequence and the second pseudo random sequence from scramble sequence, obtains the scrambler sequence for scrambling or descrambling.

2. the generation method of pseudo random sequence in LTE system according to claim 1, is characterized in that: the method producing the mask code sequence of the first pseudo random sequence in described step 2:

Step 211, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the first pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described first pseudo random sequence is x ₁(0)=1, x ₂(n)=0; N=1...30, N _cvalue be 1600;

Step 212, the initial value of the first pseudo random sequence obtained according to step 1 set up the first pseudo random sequence from scramble sequence generator polynomial:

x ₁(n+31)＝(x ₁(n)+x ₁(n+3))mod2；

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 213, according to the initial value of the first pseudo random sequence, the figure place N of scrambler sequence generation that step 1 obtains _cvalue and the mask code sequence M obtaining the first pseudo random sequence from scramble sequence generator polynomial of the first pseudo random sequence that determines of step 212 ₁; Wherein:

M ₁＝[0101111001001000010110000100000]。

3. the generation method of pseudo random sequence in LTE system according to claim 1, is characterized in that: in described step 3 first pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_1(1600+n)=\left(sum\right(\[x_1\left(0+n\right)x_1\left(1+n\right)x_1\left(2+n\right)......x_1\left(30+n\right)\]*M_1^T\left)\right)\mathrm{mod}2$

Wherein, x ₁be the first pseudo random sequence, n is scrambler sequence figure place, and mod is mod, M ₁be the mask code sequence of the first pseudo random sequence, M ₁=[0101111001001000010110000100000].

4. the generation method of pseudo random sequence in LTE system according to claim 1, is characterized in that: the method producing the mask code sequence of the second pseudo random sequence in described step 2:

Step 221, the figure place N that scrambler sequence produces in LTE system determined by the initial value according to the second pseudo random sequence of step 1 acquisition _cvalue, wherein, the initial value of described second pseudo random sequence is x ₂(0)=1, x ₂(n)=0; N=1...30, the figure place N that scrambler sequence produces _cvalue be 1600;

Step 222, the initial value of the second pseudo random sequence obtained according to step 1 set up the second pseudo random sequence from scramble sequence generator polynomial:

x ₂(n+31)＝(x ₂(n)+x ₂(n+1)+x ₂(n+2)+x ₂(n+3))mod2；

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and n is the integer from 0 to 30, and mod is mod;

Step 223, defines 31 phase sequences, is respectively:

α ₀(0)＝1,α ₀(n)＝0；n＝1...30

α ₁(1)＝1,α ₁(n)＝0；n＝0,2...30

α ₂(2)＝1,α ₂(n)＝0；n＝0...1,3...30

……

α ₃₀(30)＝1,α ₃₀(n)＝0；n＝0...29；

These 31 phase sequences form one group of base, represent any one sequence of 31;

Step 224, according to step 222 set up the second pseudo random sequence set up mask code sequence generator polynomial from scramble sequence generator polynomial:

x ₂(n+1600)

＝sum[x ₂(n+1)x ₂(n+2)x ₂(n+3)x ₂(n+8)x ₂(n+12)x ₂(n+16)x ₂(n+19)x ₂(n+20)x ₂(n+23)]mod2；

31 phase sequences step 223 defined obtain the mask code sequence (M corresponding to 31 phase sequences by mask code sequence generator polynomial successively _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}), and then obtain mask code matrix M ₂:

M ₂＝[M _α0；M _α1；M _α2；...；M _α30]；

＝[0111000010001000100110010000000；

0100100011001100110101011000000；

1010100111011101111001111000000；

1111011111111111000001110000011；

0000111111111110000011100000111；

0001111111111100000111000001110；

0011111111111000001110000011100；

0111111111110000011100000111000；

1111111111100000111000001110000；

0001111111000001110000011100001；

0011111110000011100000111000010；

0111111100000111000001110000100；

1111111000001110000011100001000；

0001110000011100000111000010001；

0011100000111000001110000100010；

0111000001110000011100001000100；

1110000011100000111000010001000；

0010000111000001110000100010001；

0100001110000011100001000100010；

1000011100000111000010001000100；

1110111000001110000100010001001；

0011110000011100001000100010011；

0111100000111000010001000100110；

1111000001110000100010001001100；

0000000011100001000100010011001；

0000000111000010001000100110010；

0000001110000100010001001100100；

0000011100001000100010011001000；

0000111000010001000100110010000；

0001110000100010001001100100000；

0011100001000100010011001000000]；

Step 225, according to the initialization value C of the initiation sequence of the second pseudo random sequence _initwith the mask code matrix M that step 224 obtains ₂=[M _{α 0}; M _{α 1}; M _{α 2}; ...; M _{α 30}] obtain the mask code sequence M of the second pseudo random sequence ₃: $M_3=M_2*C_{init}^T.$

5. the generation method of pseudo random sequence in LTE system according to claim 1, is characterized in that: in described step 3 second pseudo random sequence after scramble sequence the 1600th from scramble sequence data:

$x_2(1600+n)=\left(sum\right(\[x_2\left(0+n\right)x_2\left(1+n\right)x_2\left(2+n\right)......x_2\left(30+n\right)\]*M_3^T\left)\right)\mathrm{mod}2;$

Wherein, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.

6. the generation method of pseudo random sequence in LTE system according to claim 5, is characterized in that: in described step 4, the formula of scrambler sequence is:

c(n)＝(x ₁(n+N _c)+x ₂(n+N _c))mod2

Wherein, c (n) scrambler sequence, x ₁be the first pseudo random sequence, x ₂be the second pseudo random sequence, n is scrambler sequence figure place, and mod is mod.