CN103220013A - Method and device of spread spectrum communication for code division multiple access (CDMA) system - Google Patents

Abstract

The invention discloses a method and a device of spread spectrum communication for a code division multiple access (CDMA) system. The method comprises obtaining four fundamental sequences according to combinations of two values of high-low electrical level codes; generating a spread spectrum sequence collection with code length of 2N through processing of N-2 levels, dividing two sequence units of the collection in a spread spectrum sequence obtained after last level processing as a group when the jth level processing is carried out, obtaining a spread spectrum sequence collection composed of orthometric spread spectrum sequences with code length of 2j+2 by combining the two sequence units a1 and a2 of each group of a last level according to set disciplines sequentially, wherein when the first level processing is carried out, the fundamental sequences are used as sequence units, and sequence units used by each follow-up level contain 2j or 2j+1 values of high-low electrical level codes; and using generated spread spectrum sequences to carry out spectrum spreading processing on transmission data to achieve the spread spectrum communication. The method and the device of spread spectrum communication for the CDMA system can reduce intersymbol interference and capacity losses brought by multi-path interference, and therefore rapid data transmission can be achieved.

Description

A kind of spectrum spread communication method and device that is applied to cdma system

Technical field

The present invention relates to wireless communication technology field, relate in particular to a kind of spectrum spread communication method and device that is applied to cdma system.

Background technology

The appearance of CDMA (Code Division Multiple Access, code division multiple access insert) technology stems from human to the demand of high-quality wireless communication more.

With FDMA (Frequency Division Multiple Access, frequency division multiple access inserts) and TDMA (Time Division Multiple Access, time division multiplexing inserts) compare, CDMA has the advantage of many uniquenesses, wherein a part is that spread spectrum communication system is intrinsic, and another part then is to be brought by technology such as soft handover and power controls.The cdma mobile communication net is by several technology be combined intos such as spread spectrum, multiple access access, beehive net and frequency reuses, contain a kind of cooperation that frequency domain, time domain and sign indicating number territory three dimensional signal are handled, therefore it to have anti-interference good, the anti-multipath decline, the secret and safe height, same frequency can be reused in a plurality of sub-districts, and desired carrier/interface ratio (C/I) can be done attributes such as trade-off less than 1 between capacity and the quality.These attributes make CDMA than other system very important advantage be arranged.

Have multipath effect (multipatheffect) in the cdma system, multipath effect is by the caused interference delay effect of the multipath transport phenomena in the radio wave propagation channel.In the radio propagation channel of reality, (comprise all wave bands), the different transmission path of many time delays is often arranged, be called the multipath phenomenon.The electrical length meeting time to time change of each paths is so the phase relation between each component fields of arrival acceptance point also is a time to time change.The interference at random of these component fields forms the decline of total received field.Phase relation between each component is different to different frequencies.Therefore, their interference effect is also different because of frequency, and this specific character is called frequency selectivity.In the broadband signal transmission, frequency selectivity may show obviously, forms intermodulation.Corresponding therewith, because there is different delay in different paths, the signal that synchronization sends is because of scattering before and after acceptance point along different paths respectively, and narrow pulse signal then forward laps.

Multipath effect is the important origin cause of formation of decline.Multipath effect all has ten minutes to seriously influence for digital communication, radar optimum detection etc.

And for cdma system, because the frequency band of actual channel is always limited, and departs from ideal characterisitics, institute is so that the signal that passes through produces linear distortion on frequency domain, diffusing effect when waveform takes place on time domain.The harm that the effect of loosing when this causes digital signal post is referred to as intersymbol interference (ISI).In addition, in wireless channel,, also can produce ISI to transfer of data owing to there is the multipath transmisstion problem.When data rate improved, the interval between data will reduce, and can't distinguish to a certain degree symbol is overlapping, produced ISI.

Cdma system has provided corresponding frequency expansion sequence set in order to realize spread spectrum, utilize frequency expansion sequence wherein to realize spread spectrum communication, but owing to there is the problem of intersymbol interference, cdma system two coded signals that will receive and the pre-assigned code signal at receiver place carry out relevant after, the initial code signal is resumed, at this moment can be subjected to the interference of other coded signal, different along with signal strength signal intensity and coded signal quantity, these disturb shared ratio also can change.

Existing C DMA system adopts fast power control and soft/means such as hard soft handover to reduce interference, but there is negative effect in these complicated means, as soft/hard soft handover can cause the shortage of code channel number, and fast power control can cause the interference higher to other coded signals.

Summary of the invention

The invention provides a kind of spectrum spread communication method and device that is applied to cdma system, utilize existing ordinary straight spreading code to carry out spread spectrum in order to solve, under not exclusively synchronous situation, the problem of correlation meeting variation.

The invention provides a kind of spectrum spread communication method that is applied to cdma system, comprising:

Combination according to two values of high-low level sign indicating number obtains 4 basic sequences;

Handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1 a2], [a1-a2], [a2 a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

Utilize the frequency expansion sequence in the frequency expansion sequence set that generates that the transmission data are carried out spread processing realization spread spectrum communication.

The present invention also provides a kind of frequency spreading device that is applied to cdma system, comprising:

The basic sequence generation unit is used for the combination according to two values of high-low level sign indicating number, obtains 4 basic sequences;

Frequency expansion sequence set generation unit, being used for handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1 a2], [a1-a2], [a2 a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

The spread spectrum communication unit is used for utilizing the frequency expansion sequence of the frequency expansion sequence set of generation that the transmission data are carried out spread processing and realizes spread spectrum communication.

Utilize spectrum spread communication method and the device that is applied to cdma system provided by the invention to have following beneficial effect: the influence that can avoid synchronous error and multidiameter delay that system is brought, this performance are vital for cdma system; Have bigger spectrum efficiency, in addition, unique spread spectrum coding technology can also reduce intersymbol interference and disturb the capacitance loss that is brought by multipath, therefore can realize transfer of data more efficiently.

Description of drawings

The spectrum spread communication method flow chart that is applied to cdma system that Fig. 1 provides for the embodiment of the invention;

Fig. 2 adds the frequency expansion sequence schematic diagram that obtains behind the Cyclic Prefix in the embodiment of the invention;

Fig. 3 is for being applied to the spread spectrum communication structure chart of cdma system in the embodiment of the invention.

Embodiment

Below in conjunction with drawings and Examples spectrum spread communication method and the device that is applied to cdma system provided by the invention illustrated in greater detail.

The influence of multipath has great influence for the performance based on cdma system, multi-path influence and intersymbol interference meeting cause synchronization discrepancy, existing spreading code is under not exclusively synchronous situation, and correlation is understood variation, and there is negative effect in the complicated means that existing minimizing is disturbed.The embodiment of the invention provides a kind of spectrum spread communication method that is applied to cdma system in order to eliminate synchronous error and multidiameter delay to the influence that system brings, and as shown in Figure 1, comprising:

Step 101, the combination according to two values of high-low level sign indicating number obtains 4 basic sequences;

In the spread spectrum field, the possible value of high-low level sign indicating number is 1 ,-1, wherein 1 represents the high level sign indicating number, and-1 represents the low level sign indicating number, and then the institute of two high-low level sign indicating numbers might value comprise: [1 1], [1-1], [11], [1-1].

Step 102, handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1 a2], [a1-a2], [a2 a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

Step 103 utilizes the frequency expansion sequence in the frequency expansion sequence set that generates that the transmission data are carried out spread processing realization spread spectrum communication.

The spectrum spread communication method that is applied to cdma system that the embodiment of the invention provides is handled step by step based on defined basic sequence, by to every group 2 of higher level ^jOr 2 ^J+1The sequence units of individual high-low level sign indicating number makes up once more, and after finishing the j level and handling, the code length of the frequency expansion sequence that obtains is 2 ^J+2Because when handling for every grade, the characteristics of utilizing higher level's sequence units to make up by identical rule, when making up, choose and guarantee orthogonal characteristic between frequency expansion sequence that combination obtains, make under not exclusively synchronous situation, correlation can variation yet, can reduce intersymbol interference and disturb the capacitance loss that is brought, therefore can realize transfer of data more efficiently by multipath.

In tdma system, in order to reduce intersymbol interference, adopt the method for particular design Cyclic Prefix, the non-Zhou Xiangguan of system can be become periodic cross-correlation.Like this can so that relevant in synchronously inaccurate aperiodic be not that 0 to become the cycle relevant, and may become 0.Preferably, present embodiment is 2 generating length ^NFrequency expansion sequence when set, further comprise: before each frequency expansion sequence that generates, add Cyclic Prefix.Therefore, each length that expands sequence is 2 ^N+ 1, like this, when synchronous error is in 1 chip chip, the Cyclic Prefix orthogonal code that present embodiment provides can guarantee complete quadrature to each other, can reach in the 2us for general satellite communication system synchronization accuracy, synchronous error can be controlled in a chip with interior (is 50kps for base band speed), so can be guaranteed based on the orthogonality of sign indicating number in the system of this CDMA frequency expansion sequence set.

The influence that utilizes solution that frequency expansion sequence set in the inventive method can be desirable with interior synchronous error and multidiameter delay system to be brought at 1 chip at multidiameter delay, this performance is vital for cdma system.Can under consumption rate less expense situation, obtain the advantage of CDMA, can be applied in the multiple wireless environment neutralized system with respect to tdma system.

Preferably, added Cyclic Prefix is last level sign indicating number value of described frequency expansion sequence before each frequency expansion sequence.

Preferably, in the processing after the first order, the sequence units in the set of higher level's frequency expansion sequence is that delegation comprises 2 ^jThe sequence of individual high-low level sign indicating number value, then: the first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of getting each frequency expansion sequence in the set of higher level's frequency expansion sequence obtain each sequence units.

Perhaps, in the processing after the first order, the sequence units in described higher level's frequency expansion sequence set is two row sequences, and every capable sequence comprises 2 ^jIndividual high-low level sign indicating number value, the first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of then getting per two frequency expansion sequences in the set of higher level's frequency expansion sequence obtain each sequence units.Therefore the first half high-low level sign indicating number value of each frequency expansion sequence or latter half high-low level sign indicating number value obtain two row sequences as delegation.

Above-mentioned when making up for every grade, preferably choose and guarantee orthogonal characteristic between frequency expansion sequence that combination obtains, after finishing the j level and handling, the code length of the frequency expansion sequence that obtains is 2 ^J+2, the compound mode that provides below in the preferred embodiment of the present invention generates the method that spreading code is gathered.

Embodiment 1

The spectrum spread communication method that is applied to cdma system in the embodiment of the invention specifically may further comprise the steps:

Step 1 according to the possible value of the institute of two high-low level sign indicating numbers, obtains 4 basic sequences;

Preferably, 4 basic sequences in the present embodiment are specially:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-1 1]；B4_2＝[-1-1]。

Step 2, to handle generated code length through the N-2 level be 2 ^NFrequency expansion sequence set, N is the integer greater than 2, therefore, can obtain code length and be 8,16, the frequency expansion sequence of 32... length, carry out j (1≤j≤when N-2) level is handled, 2 sequence units gathering in higher level's frequency expansion sequence are classified as one group, do not have identical sequence units on the same group, carry out the first order when handling, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence is for comprising 2 ^jThe sequence units of individual high-low level sign indicating number value;

Make up in the following manner by 2 sequence units to every group of higher level successively:

If Mod ((i-1), 4)+1=1, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1) A2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1)-A2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2) A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2)-A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=1, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1) B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1)-B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+2) B2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+2)-B2 ^N-1_ ((i-1)/4+1)];

Wherein, i is 1,2...2 ^N-1, A2 ^N-1_ ((i-1)/4+1), A2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ ((i-1)/4+1), B2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence, A2 ^N-1_ ((i-1)/4+1), A2 ^N-1_ ((i-1)/4+2), B2 ^N-1_ ((i-1)/4+1), B2 ^N-1_ ((i-1)/4+2) is the different sequence units in higher level's frequency expansion sequence;

Combination [A2 ^N_ i B2 ^N_ i] obtain frequency expansion sequence set at the corresponding levels, therefore the code length of the frequency expansion sequence of sequence at the corresponding levels is 2 ^J+2

Code length with frequency expansion sequence is 8 and 16 pairs of above-mentioned being illustrated below, and other code length as stated above.

4 basic sequences are specially:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-11]；B4_2＝[-1-1]。

Then length is that can sample following method of 8 sign indicating number generates: N=3, determine to carry out one-level and handle:

A8_1＝[A4_1 A4_2]＝[ 1 1-1 1]

A8_2＝[A4_1-A4_2]＝[ 1 1 1-1]

A8_3＝[A4_2 A4_1]＝[-1 1 1 1]

A8_4＝[A4_2-A4_1]＝[-1 1-1-1]

B8_1＝[B4_1 B4_2]＝[ 1-1-1-1]

B8_2＝[B4_1-B4_2]＝[ 1-1 1 1]

B8_3＝[B4_2 B4_1]＝[-1-1 1-1]

B8_4＝[B4_2-B4_1]＝[-1-1-1 1]

Carrying out following combination, to obtain code length be 8 frequency expansion sequence:

[A8_1 B8_1]

[A8_2 B8_2]

[A8_3 B8_3]

[A8_4 B8_4]

And the like.

For code length is that the method that 16 frequency expansion sequence can be sampled following generates: N=4, determine to carry out 2 grades of processing, and after finishing above-mentioned one-level and handling, carry out the 2nd grade of following processing:

A16_1＝[A8_1 A8_2]

A16_2＝[A8_1-A8_2]

A16_3＝[A8_2 A8_1]

A16_4＝[A8_2-A8_1]

A16_5＝[A8_3 A8_4]

A16_6＝[A8_3-A8_4]

A16_7＝[A8_4 A8_3]

A16_8＝[A8_4-A8_3]

B16_1＝[B8_1 B8_2]

B16_2＝[B8_1-B8_2]

B16_3＝[B8_2 B8_1]

B16_4＝[B8_2-B8_1]

B16_5＝[B8_3 B8_4]

B16_6＝[B8_3-B8_4]

B16_7＝[B8_4 B8_3]

B16_8＝[B8_4-B8_3]

Carrying out following combination, to obtain length be 16 frequency expansion sequence:

[A16_1 B16_1]

[A16_2 B16_2]

[A16_3 B16_3]

[A16_4 B16_4]

[A16_5B16_5]

[A16_6B16_6]

[A16_7B16_7]

[A16_8B16_8]

Be 32 frequency expansion sequence for code length, no longer provide detailed process here.

Frequency expansion sequence set for generating is adding Cyclic Prefix at last, as shown in Figure 2, is that 16 frequency expansion sequence set is as shown in table 1 for code length, and in the table 1, each row is represented a frequency expansion sequence.

Table 1

1	1	1	-1	1	1	1	1	-1	1	-1	-1	-1	1	-1	1	1
																	-1	1	1	-1	1	-1	-1	-1	1	1	-1	-1	-1	-1	1	-1	-1
-1	1	1	1	-1	1	1	-1	1	1	-1	1	1	1	-1	-1	-1
																	1	1	1	1	-1	-1	-1	1	-1	1	-1	1	1	-1	1	1	1
1	-1	1	1	1	-1	1	-1	-1	-1	-1	1	-1	-1	-1	-1	1
																	-1	-1	1	1	1	1	-1	1	1	-1	-1	1	-1	1	1	1	-1
-1	-1	1	-1	-1	-1	1	1	1	-1	-1	-1	1	-1	-1	1	-1
																	1	-1	1	-1	-1	1	-1	-1	-1	-1	-1	-1	1	1	1	-1	1

Step 3, the frequency expansion sequence that utilize to generate are carried out spread processing to the transmission data and are realized spread spectrum communication, specifically select the mechanism of frequency expansion sequence and how to utilize frequency expansion sequence to carry out spread spectrum and can adopt current mechanism, no longer describe in detail here.

Embodiment 2

The spectrum spread communication method that is applied to cdma system in the embodiment of the invention specifically may further comprise the steps:

Step 1 according to the possible value of the institute of two level sign indicating numbers, obtains 4 basic sequences;

Preferably, 4 basic sequences in the present embodiment are specially:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-1 1]；B4_2＝[-1-1]。

Step 2, handling generated code length through the N-2 level is 2 ^NFrequency expansion sequence set, N is the integer greater than 2, therefore, can obtain code length and be 8,16, the frequency expansion sequence of 32... length, carry out j (1≤j≤when N-2) level is handled, 2 sequence units gathering in higher level's frequency expansion sequence are classified as one group, do not have identical sequence units on the same group, carry out the first order when handling, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence is for comprising 2 ^J+1The sequence units of individual high-low level sign indicating number value;

Make up in the following manner by 2 sequence units to every group of higher level successively:

${A2}^N\_1=\left[\begin{array}{cc}{A2}^{N-1}\_1& {A2}^{N-1}\_2\\ {A2}^{N-1}\_1& {-A2}^{N-1}\_2\end{array}\right]$

${A2}^N\_2=\left[\begin{array}{cc}{A2}^{N-1}\_2& {A2}^{N-1}\_1\\ {A2}^{N-1}\_2& {-A2}^{N-1}\_1\end{array}\right]$

${B2}^N\_1=\left[\begin{array}{cc}{B2}^{N-1}\_1& {B2}^{N-1}\_2\\ {B2}^{N-1}\_1& {-B2}^{N-1}\_2\end{array}\right]$

${B2}^N\_2=\left[\begin{array}{cc}{B2}^{N-1}\_2& {B2}^{N-1}\_1\\ {B2}^{N-1}\_2& {-B2}^{N-1}\_1\end{array}\right]$

A2 ^N-1_ 1, A2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ 1, B2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence, A2 ^N-1_ 1, A2 ^N-1_ 2, B2 ^N-1_ 1, B2 ^N-1_ 2 is different sequence units in the combination of higher level's frequency expansion sequence;

Combination $\left[\begin{array}{cc}{A2}^N\_1& {B2}^N\_1\\ {A2}^N\_2& {-B2}^N\_2\end{array}\right]$ Obtain frequency expansion sequence set at the corresponding levels.

Code length with frequency expansion sequence is 8 and 16 pairs of above-mentioned being illustrated below, and other code length as stated above.

4 basic sequences are specially:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-1 1]；B4_2＝[-1-1]。

Then length is that can sample following method of 8 sign indicating number generates: N=3, determine to carry out one-level and handle:

$A8\_1=\left[\begin{array}{cc}A4\_1& A4\_2\\ A4\_1& -A4\_2\end{array}\right]=\left[\begin{array}{cccc}1& 1& -1& 1\\ 1& 1& 1& -1\end{array}\right]$

$A8\_2=\left[\begin{array}{cc}A4\_2& A4\_1\\ A4\_2& -A4\_1\end{array}\right]=\left[\begin{array}{cccc}-1& 1& 1& 1\\ -1& 1& -1& -1\end{array}\right]$

$B8\_1=\left[\begin{array}{cc}B4\_1& B4\_2\\ B4\_1& -B4\_2\end{array}\right]=\left[\begin{array}{cccc}1& -1& -1& -1\\ 1& -1& 1& 1\end{array}\right]$

$B8\_2=\left[\begin{array}{cc}B4\_2& B4\_1\\ B4\_2& -B4\_1\end{array}\right]\left[\begin{array}{cccc}-1& -1& 1& -1\\ -1& -1& -1& -1\end{array}\right]$

Carrying out following combination, to obtain length be 8 frequency expansion sequence:

[A8_1 B8_1]

[A8_2 B8_2]

And the like.

For code length is that the method that 16 frequency expansion sequence can be sampled following generates: N=4, determine to carry out 2 grades of processing, and after finishing above-mentioned one-level and handling, carry out the 2nd grade of following processing:

$A16\_1=\left[\begin{array}{cc}A8\_1& A8\_2\\ A8\_2& -A8\_2\end{array}\right]$

$A16\_2=\left[\begin{array}{cc}A8\_2& A8\_1\\ A8\_2& -A8\_1\end{array}\right]$

$B16\_1=\left[\begin{array}{cc}B8\_1& B8\_2\\ B8\_2& -B8\_2\end{array}\right]$

$B16\_2=\left[\begin{array}{cc}B8\_2& B8\_1\\ B8\_2& -B8\_1\end{array}\right]$

Carrying out following combination, to obtain code length be 16 frequency expansion sequence:

[A16_1 B16_1]

[A16_2 B16_2]

Be 32 frequency expansion sequence for code length, generative process is not described in detail in detail here.

Frequency expansion sequence set for generating is adding Cyclic Prefix at last, and as being that 16 frequency expansion sequence set is as shown in table 2 for code length, in the table 2, each row is represented a frequency expansion sequence.

Table 2

-1	1	1	-1	1	-1	1	1	1	1	-1	-1	-1	-1	-1	1	-1
																	1	1	1	1	-1	-1	1	-1	-1	1	-1	1	1	-1	-1	-1	1
1	1	1	-1	1	1	-1	-1	-1	1	-1	-1	-1	1	1	-1	1
																	-1	1	1	1	-1	1	-1	1	1	1	-1	1	1	1	1	1	-1
-1	-1	1	1	1	1	1	-1	1	-1	-1	1	-1	1	-1	-1	-1
																	1	-1	1	-1	-1	1	1	1	-1	-1	-1	-1	1	1	-1	1	1

1	-1	1	1	1	-1	-1	1	-1	-1	-1	1	-1	-1	1	1	1
																	-1	-1	1	-1	-1	-1	-1	-1	1	-1	-1	-1	1	-1	1	-1	-1

Step 3 is utilized the frequency expansion sequence that generates that the transmission data are carried out spread processing and is realized spread spectrum communication.

The method of utilizing the embodiment of the invention to provide, can construct length is 2 ^NFrequency expansion sequence, realize spread spectrum communication based on this frequency expansion sequence, synchronism deviation is that the number of circumference orthogonal code is 2 in 1chip between wherein any two frequency expansion sequences ^N-1Compare with other 3G technologies, the most outstanding characteristics of the present invention are exactly to have bigger spectrum efficiency, and in addition, unique coding techniques can also reduce intersymbol interference and disturb the capacitance loss that is brought by multipath, therefore can realize transfer of data more efficiently.

Based on same inventive concept, traffic load equilibrium treatment equipment between a kind of subframe, a kind of presence of intercell interference treatment facility also are provided in the embodiment of the invention, because the principle that these equipment are dealt with problems is similar to traffic load equalization processing method, a kind of presence of intercell interference processing method between a kind of subframe, therefore the enforcement of these equipment can repeat part and repeat no more referring to the enforcement of method.

The frequency spreading device that is applied to cdma system that the embodiment of the invention provides as shown in Figure 3, comprising:

Basic sequence generation unit 301 is used for the combination according to two values of high-low level sign indicating number, obtains 4 basic sequences;

Frequency expansion sequence set generation unit 302, being used for handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1a2], [a1-a2], [a2a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

Spread spectrum communication unit 303 is used for utilizing the frequency expansion sequence of the frequency expansion sequence set of generation that the transmission data are carried out spread processing and realizes spread spectrum communication.

Those skilled in the art should understand that embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt complete hardware embodiment, complete software implementation example or in conjunction with the form of the embodiment of software and hardware aspect.And the present invention can adopt the form that goes up the computer program of implementing in one or more computer-usable storage medium (including but not limited to magnetic disc store, CD-ROM, optical memory etc.) that wherein include computer usable program code.

The present invention is that reference is described according to the flow chart and/or the block diagram of method, equipment (system) and the computer program of the embodiment of the invention.Should understand can be by the flow process in each flow process in computer program instructions realization flow figure and/or the block diagram and/or square frame and flow chart and/or the block diagram and/or the combination of square frame.Can provide these computer program instructions to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, make the instruction of carrying out by the processor of computer or other programmable data processing device produce to be used for the device of the function that is implemented in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame appointments.

These computer program instructions also can be stored in energy vectoring computer or the computer-readable memory of other programmable data processing device with ad hoc fashion work, make the instruction that is stored in this computer-readable memory produce the manufacture that comprises command device, this command device is implemented in the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

These computer program instructions also can be loaded on computer or other programmable data processing device, make on computer or other programmable devices and to carry out the sequence of operations step producing computer implemented processing, thereby the instruction of carrying out on computer or other programmable devices is provided for being implemented in the step of the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

Although described the preferred embodiments of the present invention, in a single day those skilled in the art get the basic creative notion of cicada, then can make other change and modification to these embodiment.So claims are intended to all changes and the modification that are interpreted as comprising preferred embodiment and fall into the scope of the invention.

Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.

Claims (14)

1. a spectrum spread communication method that is applied to cdma system is characterized in that, comprising:

Combination according to two values of high-low level sign indicating number obtains 4 basic sequences;

Handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1 a2], [a1-a2], [a2 a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

Utilize the frequency expansion sequence in the frequency expansion sequence set that generates that the transmission data are carried out spread processing realization spread spectrum communication.

2. the method for claim 1 is characterized in that, is 2 in generated code length ^NFrequency expansion sequence when set, further comprise:

Before each frequency expansion sequence that generates, add Cyclic Prefix.

3. method as claimed in claim 2 is characterized in that,

Added Cyclic Prefix is last level sign indicating number value of described frequency expansion sequence before each frequency expansion sequence.

4. the method for claim 1 is characterized in that, in the processing after the first order, the sequence units in the set of higher level's frequency expansion sequence is that delegation comprises 2 ^jThe sequence of individual high-low level sign indicating number value, then:

The first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of getting each frequency expansion sequence in the set of higher level's frequency expansion sequence obtain each sequence units; Perhaps

In the processing after the first order, the sequence units in described higher level's frequency expansion sequence set is two row sequences, and every capable sequence comprises 2 ^jIndividual high-low level sign indicating number value, then

The first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of getting per two frequency expansion sequences in the set of higher level's frequency expansion sequence obtain each sequence units.

5. as the arbitrary described method of claim 1～4, it is characterized in that in the processing after the first order, the sequence units in described higher level's frequency expansion sequence set comprises 2 ^jIndividual high-low level sign indicating number value, during every grade of processing, 2 sequence units a1, a2 combinations to every group of higher level obtain frequency expansion sequence set at the corresponding levels successively, comprising:

If Mod ((i-1), 4)+1=1, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1) A 2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1)-A2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2) A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2)-A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=1, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1) B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1)-B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+2) B2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then B2 ^N_I=[B2 ^N-1_ ((i-1)/4+2)-B2 ^N-1_ ((i-1)/4+1)];

Wherein, i is 1,2...2 ^N-1, A2 ^N-1_ ((i-1)/4+1), A2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ ((i-1)/4+1), B2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence;

Combination [A2 ^N_ i B2 ^N_ i] obtain frequency expansion sequence at the corresponding levels set.

6. as the arbitrary described method of claim 1～4, it is characterized in that the sequence units in described higher level's frequency expansion sequence set comprises 2 ^J+1Individual high-low level sign indicating number value, during every grade of processing, 2 sequence units a1, a2 combinations to every group of higher level obtain frequency expansion sequence set at the corresponding levels successively, comprising:

${A2}^N\_1=\left[\begin{array}{cc}{A2}^{N-1}\_1& {A2}^{N-1}\_2\\ {A2}^{N-1}\_1& {-A2}^{N-1}\_2\end{array}\right]$

${A2}^N\_2=\left[\begin{array}{cc}{A2}^{N-1}\_2& {A2}^{N-1}\_1\\ {A2}^{N-1}\_2& {-A2}^{N-1}\_1\end{array}\right]$

${B2}^N\_1=\left[\begin{array}{cc}{B2}^{N-1}\_1& {B2}^{N-1}\_2\\ {B2}^{N-1}\_1& {-B2}^{N-1}\_2\end{array}\right]$

${B2}^N\_2=\left[\begin{array}{cc}{B2}^{N-1}\_2& {B2}^{N-1}\_1\\ {B2}^{N-1}\_2& {-B2}^{N-1}\_1\end{array}\right]$

A2 ^N-1_ 1, A2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ 1, B2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence;

Combination $\left[\begin{array}{cc}{A2}^N\_1& {B2}^N\_1\\ {A2}^N\_2& {-B2}^N\_2\end{array}\right]$ Obtain frequency expansion sequence set at the corresponding levels.

7. as the arbitrary described method of claim 1～4, it is characterized in that 4 basic sequences are specially:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-1 1]；B4_2＝[-1-1]。

8. as the arbitrary described method of claim 1～4, it is characterized in that the code length of frequency expansion sequence is 8,16 or 32 in the frequency expansion sequence set of generation.

9. a frequency spreading device that is applied to cdma system is characterized in that, comprising:

The basic sequence generation unit is used for the combination according to two values of high-low level sign indicating number, obtains 4 basic sequences;

Frequency expansion sequence set generation unit, being used for handling generation through the N-2 level is 2 by code length ^NThe frequency expansion sequence set formed of frequency expansion sequence, N is the integer greater than 2, when carrying out the processing of j level, 2 sequence units gathering in the frequency expansion sequence that obtains after higher level's processing are divided into one group, and there is not identical sequence units on the same group, by successively to every group of higher level's 2 sequence units a1, a2 according to [a1 a2], [a1-a2], [a2 a1], [a2-a1] combination, obtaining by code length is 2 ^J+2The frequency expansion sequence set formed of frequency expansion sequence, wherein mutually orthogonal between each frequency expansion sequence, when carrying out first order processing, the sequence units in described higher level's frequency expansion sequence set is a basic sequence, during every grade of processing afterwards, the sequence units in the set of higher level's frequency expansion sequence comprises 2 ^jOr 2 ^J+1Individual high-low level sign indicating number value, 1≤j≤N-2;

The spread spectrum communication unit is used for utilizing the frequency expansion sequence of the frequency expansion sequence set of generation that the transmission data are carried out spread processing and realizes spread spectrum communication.

10. device as claimed in claim 9 is characterized in that, frequency expansion sequence set generation unit is 2 in generated code length ^NFrequency expansion sequence when set, before each frequency expansion sequence that generates, add Cyclic Prefix.

11. device as claimed in claim 9 is characterized in that, in the processing after the first order, the sequence units in the set of higher level's frequency expansion sequence is that delegation comprises 2 ^jThe sequence of individual high-low level sign indicating number value, then:

Frequency expansion sequence set generation unit, the first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of getting each frequency expansion sequence in the set of higher level's frequency expansion sequence obtain each sequence units; Perhaps

In the processing after the first order, the sequence units in described higher level's frequency expansion sequence set is two row sequences, and every capable sequence comprises 2 ^jIndividual high-low level sign indicating number value, then

Frequency expansion sequence set generation unit, the first half high-low level sign indicating number value or the latter half high-low level sign indicating number value of getting per two frequency expansion sequences in the set of higher level's frequency expansion sequence obtain each sequence units.

12., it is characterized in that in the processing after the first order, the sequence units in described higher level's frequency expansion sequence set comprises 2 as the arbitrary described device of claim 9～11 ^jIndividual high-low level sign indicating number value, frequency expansion sequence set generation unit specifically is used for carrying out following processing at every grade:

If Mod ((i-1), 4)+1=1, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1) A2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+1)-A2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2) A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then A2 ^N_ i=[A2 ^N-1_ ((i-1)/4+2)-A2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=1, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1) B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=2, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+1)-B2 ^N-1_ ((i-1)/4+2)];

If Mod ((i-1), 4)+1=3, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+2) B2 ^N-1_ ((i-1)/4+1)];

If Mod ((i-1), 4)+1=4, then B2 ^N_ i=[B2 ^N-1_ ((i-1)/4+2)-B2 ^N-1_ ((i-1)/4+1)];

Wherein, i is 1,2...2 ^N-1, A2 ^N-1_ ((i-1)/4+1), A2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ ((i-1)/4+1), B2 ^N-1_ ((i-1)/4+2) is one group of sequence units in the set of higher level's frequency expansion sequence;

Combination [A2 ^N_ i B2 ^N_ i] obtain frequency expansion sequence at the corresponding levels set.

13., it is characterized in that in the processing after the first order, the sequence units in described higher level's frequency expansion sequence set comprises 2 as the arbitrary described device of claim 9～11 ^J+1Individual high-low level sign indicating number value, frequency expansion sequence set generation unit specifically is used for carrying out following processing at every grade:

${A2}^N\_1=\left[\begin{array}{cc}{A2}^{N-1}\_1& {A2}^{N-1}\_2\\ {A2}^{N-1}\_1& {-A2}^{N-1}\_2\end{array}\right]$

${A2}^N\_2=\left[\begin{array}{cc}{A2}^{N-1}\_2& {A2}^{N-1}\_1\\ {A2}^{N-1}\_2& {-A2}^{N-1}\_1\end{array}\right]$

${B2}^N\_1=\left[\begin{array}{cc}{B2}^{N-1}\_1& {B2}^{N-1}\_2\\ {B2}^{N-1}\_1& {-B2}^{N-1}\_2\end{array}\right]$

${B2}^N\_2=\left[\begin{array}{cc}{B2}^{N-1}\_2& {B2}^{N-1}\_1\\ {B2}^{N-1}\_2& {-B2}^{N-1}\_1\end{array}\right]$

A2 ^N-1_ 1, A2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence, B2 ^N-1_ 1, B2 ^N-1_ 2 are one group of sequence units in the set of higher level's frequency expansion sequence;

Combination $\left[\begin{array}{cc}{A2}^N\_1& {B2}^N\_1\\ {A2}^N\_2& {-B2}^N\_2\end{array}\right]$ Obtain frequency expansion sequence set at the corresponding levels.

14., it is characterized in that 4 basic sequences that the basic sequence generation unit generates are specially as the arbitrary described device of claim 9～11:

A4_1＝[1 1]；B4_1＝[1-1]

A4_2＝[-1 1]；B4_2＝[-1-1]。

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