CN101447805A - Receiving device and receiving method - Google Patents

Abstract

The invention relates to a receiving device and a receiving method, comprising: a signal receiving part, a receiving side filtering part, a code generating part, a code side filtering part and a relevant demodulation part. The receiving side filtering part and the code side filtering part are all filters for a prescriptive real pulse constant r, a prescriptive real constant x, a prescriptive delay time constant D and a prescriptive positive integer M, wherein the filters comprise: input terminals; delaying and amplifying parts for outputting M signals after delaying and amplifying the received input signals by a delay time t0 and a magnification ratio a0, a delay time t1 and a magnification ratio a1, ... , and a delay time t<M-1> and a magnification ratio a<M-1> respectively; addition parts for outputting a summation of the outputted M signals after delay and amplification; out terminals for outputting signals after addition, wherein t0, t1, ... , and t<M-1> is an arithmetic progression of common difference D, and a0, a1, ... , and a<M-1> is a geometric progression with first term X and common ratio -r or -1/r.

Description

Receiving system and method for reseptance

The application is to be on March 26th, 2002 applying date, application number is 02807370.3, and denomination of invention is divided an application for the application of " output intent and the program of the output device of filter, receiving system, dispensing device, band spectrum modulation device, pseudo-random number sequence, filtering method, method of reseptance, sending method, spread spectrum modulation technique, pseudo-random number sequence ".

Technical field

The present invention relates to a kind of receiving system and method for reseptance.

These inventions are suitable for realizing to can be used for for example satellite communication, fixed communication, portable phone or PHS land mobiles such as (Personal Handyphone System) or GPS (asynchronous CDMA (the Code DivisionMultiple Access of the spread spectrum communication in the range finding field such as Global Positioning-System); Code division multiple access) the useful Filtering Processing of mode obtains can be used as the pseudo-random number sequence of spreading code.

Background technology

In the past, as the spreading code of realizing spread spectrum communication, CDMA communication, proposed by linear feedback shift register (Linear Feedback Shift Register; LFSR) the M sequence of Xing Chenging, volume sign indicating number, Gold sequence etc.In these spreading code system sign indicating numbers following two features are arranged.

1st, have a peak value in same code relevant (auto-correlation) each other, different sign indicating numbers relevant (cross-correlation) each other is 0.This is very similar to white noise (white noise).

2nd, constituting the sign indicating number set, so that under the situation of two the different spreading codes that comprise, which no matter is selected in the option code set, its cross-correlation is all near 0, and at this moment, the relative code length N of number of codes that comprises in the sign indicating number set only is 0 (N).Therefore, Ma kind is few.

In addition, also knew TDMA (Time Division Multiple Access in the past; Time division multiple access) or FDMA (Frequency Division Multiple Access; Frequency division multiple access).Asynchronous cdma communication system is different therewith, does not actively obtain the feature that signal Synchronization can utilize the correlation properties of used sign indicating number to decode although have.Therefore, latent words property, invisible, anti-interference, obstruction property etc. are good.

Current, asynchronous cdma communication system development practicability, decision is used as ITU (the International Telecommunication Union) standard basis of the next generation wireless communication of so-called IMT-2000 (International Mobile Telecommunication 2000).

Research by in recent years as can be known, in asynchronous cdma communication system, the variances sigma decision systems performance of intersymbol interference noise.This variances sigma with pseudo-white noises such as Gold sign indicating number or volume sign indicating numbers as under the situation of spreading code, if will connect number of users simultaneously is made as K, code length is made as N, then asymptoticly be

σ=(K-1)/3N is shown in for example following document.

M.B.Pursley，[Performance?Evaluation?for?Phased—Coded?Spread—Spectrum?Multiple—Access?Communication—Part?I：System?Analysis](IEEETrans.Communications，vol.25(1997)pp.795—799.)

Here, so-called asymptotic number of users K and the code length N of being meant gets the situation of big value.

In the past, thought that the performance logic boundary of asynchronous cdma communication system was σ=(K-1)/3N.But to come from spreading code be pseudo-white noise in the establishment of this asymptotic relation as can be known.

Therefore, not under the situation of pseudo-white noise at spreading code, promptly different intersymbols exist under several relevant situations, and the logic boundary of performance also may improve.

Recently, find to exist and spreading code is the spreading code that the auto-correlation function that the variances sigma of intersymbol interference noise reduces was compared, had to the situation of pseudo-white noise.That is, the shift amount s of auto-correlation function C (s) relocatable code as

Be like that under the situation of exponential function minimizing, it is also littler than the situation of pseudo-white noise that the variances sigma of interference noise becomes.

Especially satisfy towards constant r at forceful pulse

r＝2—3 ^1/2

Situation under, adopt

σ _optimal＝3 ^1/2(K—1)/(6N)

Etc. best correlation function form.

This is to connect number of users K because of time under the same bit error rate also to have increased by 15% than the logic boundary that pseudo-white noise is used as the number of users of the asynchronous cdma communication system under the spreading code situation.Be disclosed in the following document about this point.

G.Mazzini，R.Rovatti，and?G.Setti[Interference?Minimization?by?Auto—Correlation?Shaping?In?Asynchronous?DS—CDMA?Systems：Chaos—BasedSpreading?Is?Nearly?Optimal](Electron.Lett.(1999)vol.35，pp.1054—1055)

In addition, in the document, the spreading code that constitutes unrest by the great multistage Linear Mapping of rate of inclining with part is shown also, modal representation satisfies the correlation function C (s) of above-mentioned condition approx.

But DSP (Digital Signal Processor) etc. is actual to generate this frequency expansion sequence and by uses such as portable phones, therefore following problem takes place for essential high speed and low consumpting power in order to use.

In a single day 1st,,, then there is the problem that the position becomes greatly, can not get correct result of leaking so in DSP or computer etc., calculate because spreading code is made of the great multistage Linear Mapping of the rate of inclining.Therefore, there is the problem that is difficult to constitute physical circuit or device and generates spreading code.

2nd, there is the problem that freely to adjust the parameter that determines the correlation function attenuation state to r (-1＜r＜1) arbitrarily.

3rd, have shown in the above-mentioned document near the kind of the multistage Linear Mapping of the correlation function of best correlation function few.But,, multiple sign indicating number is arranged as far as possible preferably in order to realize cdma communication system.Therefore, use that disclosed method is difficult to constitute realistically cdma communication system in the above-mentioned document.

4th, in the spreading code that uses linear shift register to generate, the relative code length N of kind of the sign indicating number that correlation properties are good only is 0 (N).With the kind of original sign indicating number quantity 0 (2 only for being directly proportional with 2 power ^N) opposite, considerably less.Therefore, be difficult to increase corresponding to number of users.

5th, because bond space is narrow, so it is few to decipher essential formality.Therefore, produce the problem that communication security dies down.

These problems are not enhanced in the disclosed technology in above-mentioned document.

Therefore, when addressing this is that, strong expectation (is also referred to as PN (Pseudo Noise by the pseudo-random number sequence that is suitable for asynchronous cdma communication system; Pseudo-noise) sequence.) generation technique of the spreading code that constitutes.

In addition, proposal in the past is based on the wireless communication technology of systems such as IMT 2000W-cdma system, 1CDMA2000 system, WLAN IEEE802.11b.In this radio communication,, utilize CDMA (Code Division MultipleAccess) for same frequency band being used for a plurality of communicating to connect.

In CDMA, the spreading code that differs from one another by use comes the band spectrum modulation communication information, can communicate to connect the access same frequency band with a plurality of, or separates communicating to connect of expectation from same frequency band.

In addition, in these radio communications, should transmit information conversion usually is to handle behind the sequence of complex numbers.

Therefore, in this wireless communication technology, require to use the good spreading code of separating property to carry out the simple and easy technology of band spectrum modulation.

And, proposed in the past orthogonal code sequence (orthogonal code sequence that comprises M sequence, Gold sign indicating number, obtains from Walsh (ウ オ Le シ ユ) function, the orthogonal code sequence, Bake sequence, the Manchester's code orthogonal sequence that obtain from Chebyshev polynomials.Below identical.) as the spread spectrum of spreading code.

For example, in wireless communication technology based on systems such as IMT 2000W-cdma system, 1CDMA2000 system, WLAN IEEE802.11b, for same frequency band being used for a plurality of communicating to connect, utilize CDMA (Code Division Multiple Access).

In CDMA, by being made as spreading code to the plural number that the key element of orthogonal code sequence is configured on real part and the imaginary part, the spreading code that use differs from one another comes the band spectrum modulation communication information, can communicate to connect the access same frequency band with a plurality of, or separates communicating to connect of expectation from same frequency band.

In this wireless communication technology, how between base station and portable terminal, to communicate, but usually at first from portable terminal to base station transmit signals (Up Link communication), after the base station receives signal, obtain synchronously, communicate between the two thus.

Therefore, when between the two communication of beginning, obtain relevantly by receiver side (be generally the base station, but also may be portable terminal) at this moment, obtain thus synchronously.

In addition, the communication (Down Link communication) after obtaining synchronously is because obtain in advance synchronously, so also can only carry out synchronous detection.

In this wireless communication technology, the better user of separating property increases, BER (Bit Error Rate even if require all the time; The error rate) the also low communication technology.

And the expectation to the general device that carries out Filtering Processing, element when addressing these problems is also big.In addition, think that this Filtering Processing is also wide in the range of application in other field.

The object of the present invention is to provide a kind of all-purpose receiving system and method for reseptance.

Summary of the invention

In order to realize above purpose, according to principle of the present invention, open following invention.

Receiving system according to the present invention possesses signal receiving part, receiver side filtering portion, sign indicating number generating unit, sign indicating number side filtering portion, correlation detection portion, following formation.

That is signal receiving part received signal.

In addition, receiver side filtering portion receives the signal that receives as list entries, and it is carried out exporting after the Filtering Processing.

And the sign indicating number generating unit generates spreading code.

Sign indicating number side filtering portion receives the spreading code that generates as list entries, it is carried out exporting after the Filtering Processing.

In addition, the result of the Filtering Processing of relocatable code side filtering portion of correlation detection portion, the result of the Filtering Processing of correlation detection receiver side filtering portion obtains transmitting signal.

Receiver side filtering portion and sign indicating number side filtering portion all are at the time of delay constant D and the above-mentioned filter of the positive integer N of regulation of regulation forceful pulse towards constant r, regulation real constant x, regulation, possess:

Input terminal is accepted the input of input signal;

Postpone the enlarging section, output will be accepted the input signal of described input respectively

With the signal after time of delay, t0, magnification ratio a0 postponed to amplify,

With the signal after time of delay, t1, magnification ratio a1 postponed to amplify,

…、

With the signal after time of delay, tM-1, magnification ratio aM-1 postponed to amplify

M signal;

Addition portion (204) exports the summation that M signal of back output amplified in described delay; With

Lead-out terminal is exported the signal of exporting after the described addition,

Wherein,

T0, t1 ..., tM-1 constitutes the equal difference number sequence row of tolerance D,

A0, a1 ..., aM-1 to constitute first be x, common ratio for-r or-the geometric ratio number sequence of 1/r is listed as.

In addition, in receiving system of the present invention, the multiple orthogonal code sequence that the sign indicating number generating unit generates orthogonal code sequence or is made of real part and the different respectively orthogonal code sequence of imaginary part, as spreading code, the orthogonal code sequence that described orthogonal code sequence comprises M sequence, Gold sign indicating number, obtain from walsh function, the orthogonal code sequence, Bake sequence, the Manchester's code orthogonal sequence that obtain from Chebyshev polynomials.

The method of reseptance of others possesses signal receiving step, receiver side filter step, sign indicating number generation step, sign indicating number side filter step, correlation detection step, following formation according to the present invention.

That is, in the signal receiving step, received signal.

In addition, in the receiver side filter step, the signal that receives is received as list entries, it is carried out exporting after the Filtering Processing.

And sign indicating number generates in the step, generates spreading code.

In the sign indicating number side filter step, the spreading code that generates is received as list entries, it is carried out exporting after the Filtering Processing.

The correlation detection step is carried out correlation detection with the result of the Filtering Processing of described receiver side filter step with respect to the result of the Filtering Processing of described sign indicating number side filter step, obtains transmitting signal.

In receiver side filter step and the sign indicating number side filter step, all by at the regulation forceful pulse towards constant r, regulation real constant x, regulation time of delay constant D and the above-mentioned filtering method of the positive integer N of regulation carry out Filtering Processing, possess:

Input step is accepted the input of input signal;

Postpone amplification procedure, output will be accepted the input signal of described input respectively

With the signal after time of delay, t0, magnification ratio a0 postponed to amplify,

With the signal after time of delay, t1, magnification ratio a1 postponed to amplify,

…、

With the signal after time of delay, tM-1, magnification ratio aM-1 postponed to amplify

M signal;

Addition step (204) is exported the summation that M signal of back output amplified in described delay; With

The output step is exported the signal of exporting after the described addition,

Wherein,

T0, t1 ..., tM-1 constitutes the equal difference number sequence row of tolerance D,

A0, a1 ..., aM-1 to constitute first be x, common ratio for-r or-the geometric ratio number sequence of 1/r is listed as.

In addition, in method of reseptance of the present invention, sign indicating number generates in the step, generates orthogonal code sequence (orthogonal code sequence that comprises M sequence, Gold sign indicating number, obtains from walsh function, the orthogonal code sequence, Bake sequence, the Manchester's code orthogonal sequence that obtain from Chebyshev polynomials.Below identical.) or the multiple orthogonal code sequence that constitutes by real part and the different respectively orthogonal code sequence of imaginary part, as spreading code.

Description of drawings

Fig. 1 is the schematic configuration diagram of modal representation pseudo-random number sequence output device of the present invention.

Fig. 2 is the profile of expression Chebyshev mapping.

Fig. 3 is the schematic construction ideograph of the available FIR filter of this example of expression.

Fig. 4 is the curve of analog result of the error rate of expression this method.

Fig. 5 is the curve of analog result of the error rate of expression this method.

Fig. 6 is the curve of analog result of the error rate of expression this method.

Fig. 7 is the curve of analog result of the error rate of expression this method.

Fig. 8 is the curve of analog result of the error rate of expression this method.

Fig. 9 is the curve of analog result of the error rate of expression this method.

Figure 10 is the curve of analog result of the error rate of expression this method.

Figure 11 is the curve of analog result of the error rate of expression this method.

Figure 12 is the curve of analog result of the error rate of expression this method.

Figure 13 is the curve of analog result of the error rate of expression this method.

Figure 14 is the curve of analog result of the error rate of expression this method.

Figure 15 is the curve of analog result of the error rate of expression this method.

Figure 16 is the flow chart of the output intent step of a pseudo-random number sequence of inventing.

Figure 17 is the schematic construction ideograph of expression dispensing device of the present invention.

Figure 18 is the key diagram of expression Direct-Spread state.

Figure 19 is the schematic construction ideograph of expression receiving system of the present invention.

Figure 20 is the ideograph that the receiving system example under the correlation detection situation is carried out in expression.

Figure 21 is the schematic construction ideograph of example of the receiving system of the expression signal that receives asynchronous transmission.

Figure 22 is the curve that expression is suitable for the analog result of the relation of number of users and BER in W-cdma system under the situation of present technique and the existing W-cdma system.

Figure 23 is the schematic construction ideograph of expression complex filter example of the present invention.

Figure 24 is that expression uses multiple filter to carry out the schematic construction ideograph of W-CDMA with the band spectrum modulation device of band spectrum modulation processing.

Figure 25 is the curve of the frequency characteristic of the multiple filter of expression.

Figure 26 is the curve of expression by the spectrum distribution of the signal of band spectrum modulation device transmission.

Embodiment

Below, example of the present invention is described.Following example is used for explanation, does not limit the scope of the invention.Therefore, it is apparent to those skilled in the art that and to adopt the example that these key elements or all key elements is replaced as the key element equivalent, but these examples also are contained in the scope of the present invention with it.

(the 1st example)

Fig. 1 is the schematic construction ideograph (data flow diagram) of the pseudo-random number sequence output device of expression the present invention the 1st example.Below, describe with reference to Fig. 1.

The forceful pulse of 101 pairs of regulations of output device of the pseudo-random number sequence of this example possesses sequential reception portion 102, calculating part 103 and efferent 104 towards the pseudo-random number sequence of real constant C (C ≠ 0) the output length N (N ≧ 1) of constant r (-1＜r＜1) and regulation.

That is, sequential reception portion 102 receive length L (L ≧ 1) spreading code (z[1], z[2] ..., z[L]) input, as the sequence initial value.

In addition, calculating part 103 is according to the z[1 that accepts input], z[2] ..., z[L], calculate positive integer M (1 ≦ M ≦ N, M+N＜L) satisfy to regulation

z’[1]＝C∑ _j＝1 ^M(—r) ^M+1-jz[j]；

z’[2]＝C∑ _j＝1 ^M(—r) ^M+1-jz[j+1]；

…

z’[N]＝C∑ _j＝1 ^M(—r) ^M+1-jz[j+N—1]

(z ' [1], z ' [2] ..., z ' [N]).

Efferent 104 output (z ' [1], z ' [2] ..., z ' [N]), as pseudo-random number sequence.

Calculating in the calculating part 103 also can realize by the combination of adder and substracter circuit and mlultiplying circuit except that can realizing by the multinomial operation of computer.In addition, also can realize, or realize by the computing of rational by the floating-point operation of carrying out the specified accuracy assurance.As described later.

Sequence initial value in the sequential reception portion 102 and the input of numeric parameter receive or the output of efferent 104 under the situation of computer through RAM (Random Access Memory) or CPU (CentralProcessing Unit; CPU) Nei register carries out, and under the situation of electronic circuit, can use latch to wait and realize.

According to above-mentioned asymptotic expression as can be known, because obtain respectively z ' [1], z ' [2] ..., the calculating of z ' [N] is independently of one another, so can come parallel computation by maximum parallelism degree N.In addition, because describe, so also can calculate easily by the computing repeatedly of circulation with asymptotic expression.

As the spreading code that becomes the sequence initial value, can use M sequence, Gold sign indicating number, volume sign indicating number, Walsh Adama orthogonal code or the mess code that generates by Chebyshev polynomials etc.Below, the mess code (caos) that generates by Chebyshev polynomials is described.

Fig. 2 is the curve of expression Chebyshev polynomials (Chebyshev Map).Chebyshev polynomials are when establishing integer a (a ≧ 0) when the number of times, as

T _a(cosθ)＝cos(aθ)

Shown in, can define by the addition theorem of cosine function.In addition, as follows, also can directly show by rational polynominal.

T ₀(x)＝1；

T ₁(x)＝x；

T ₂(x)＝2x ²—1；

T ₃(x)＝4x ³—3x

The Chebyshev polynomials y=T of a ≧ 1 _a(x) all be the Rational Map that open interval-1＜x＜1 is mapped to open interval-1＜y＜1.

Among Fig. 2, with y=T ₂(x), y=T ₃(x), y=T ₄(x), y=T ₅The Chebyshev polynomials of form curve representation number of times from 2 to 5 (x).Transverse axis is the x axle, and the longitudinal axis is the y axle.

As the mess code that uses this Chebyshev polynomials to generate, consider following situation.

1st, as the most basic mess code, calculate by following asymptotic expression.

z[i+1]＝T _a(z[i])

2nd, be mess code after it is used, use asymptotic expression

y _j[1]＝Y _j；

y _j[m+1]＝T(p _j，y _j[m])；

z[n]＝∏ _j＝1 ^sT(q _j，y _j[n])

Wherein, and T (a, x)=T _a(x)

Come sequence of calculation initial value Y ₁, Y ₂..., Y _s(-1＜Y ₁＜1 ,-1＜Y ₂＜1 ... ,-1＜Y _s＜1), regulation integer constant q ₁, q ₂..., q _s, regulation numeric parameter p ₁, p ₂..., p _s(wherein, q ₁Mod p ₁≠ 0, q ₂Mod p ₂≠ 0 ..., q _sMod p _s≠ 0).

(theoretical background 1)

The correlation function of the pseudo-random number sequence of the length N of exporting when using the mess code of Chebyshev polynomials becomes Lebesgue frequency spectrum (LebesgueSpectrum) theory that above-mentioned best correlation function launches in ergodic theory.This theory is disclosed in the following document.

V.I.Arnold?and?A.Avez[Ergodic?Problems?of?Classical?Mechanics](W.A.Benjamin，New?York，1968)

Below, the Lebesgue Frequency Spectral Theory is described.

Now, establish from what is called

X _n+1＝F(X _n)

The sequence that generates of mechanical system

X ₁、X ₂、...

Limiting density distribution function (invariant measure) ρ (x) dx on the regional Q of this mechanical system of definition has traversal (エ Le go-De) property relatively.

At this moment, according to inner product about this invariant measure

<u，v>＝∫Qu(x)v(x)ρ(x)dx

Can consider that nature is defined as mould side's computing ‖ ‖

‖v‖ ²＝<u，v>

Hilbert space L ₂

According to above-mentioned document, at this L ₂The normal state quadrature basis of the particular matter that depends on certain optical system is satisfied in unique existence in the space

{φ _λ，j} _{λ∈Λ，j∈J}

Be referred to as the Lebesgue frequency spectrum.

Here, λ is the coefficient to all kinds of additional level of this Lebesgue frequency spectrum, and j is corresponding to the integer more than 0 that a unlimited addition is arranged under the grade of this each class function of indication.

According to this definition, the Lebesgue frequency spectrum is the normal state orthogonal function system that is made of a unlimited function as can be known.Especially under the unlimited situation of the kind quantity (cardinality of Λ) that adopts grade λ, this Lebesgue frequency spectrum is called unlimited Lebesgue frequency spectrum.In addition, be not only normal state quadrature basis and at L at this Lebesgue frequency spectrum ₂Be under the situation on complete normal state quadrature basis in the space, this Lebesgue frequency spectrum is called complete Lebesgue frequency spectrum.

In addition, the special nature that so-called above-mentioned Lebesgue frequency spectrum has is meant all λ ∈ Λ, j ∈ J, satisfies

φ _λ，j○F＝φ _λ，j+1

Wherein,

(f○g)(x)＝f(g(x))

That is, if function is provided

φ _λ，0，

Then to the Lebesgue frequency spectrum function of j ≧ 1 of class λ

φ _λ，j，

Can all obtain by the mapping F () that is suitable for the definition mechanical system repeatedly.

In addition, form normal state rhombic system, each function by hypothesis Lebesgue frequency spectrum

φ _λ，j

With the relative of a sort function of other j ≠ j ' arbitrarily

φ _λ，j’

With to any function of the λ ≠ λ ' of other class

φ _λ’，j“

Quadrature.

As traversal mechanical system, the chaotic mechanical system of Chebyshev that is provided by the Chebyshev polynomials more than 2 times described later is arranged with complete Lebesgue frequency spectrum.The chaotic mechanical system of Chebyshev is disclosed in the following document.

R.L.Adler，T.J.Rivlin[Proc.Am.Math.Soc.15](1964，p794)

Now, establish L ₂Certain function B (x) can resemble

$B\left(x\right)={\mathrm{\&Sigma;}}_{j=1}^N{a}_{\mathrm{\&lambda;},j}{\mathrm{\&phi;}}_{\mathrm{\&lambda;},j}\left(x\right)$

Launch by the Lebesgue frequency spectrum like that.

At this moment, correlation function

<B(x)B(F ¹(x))>≡<B ₀，B ₁>

According to the orthogonality of Lebesgue frequency spectrum, as

$<{\mathrm{<figure-callout\; id="0"\; label="B"\; filenames="A200810166113E00351.png,A200810166113E00371.png"\; state="\{\{state\}\}">B</figure-callout>}}_0,{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="A200810166113E00351.png,A200810166113E00501.png"\; state="\{\{state\}\}">B</figure-callout>}}_1>={\mathrm{\&Sigma;}}_{m=1}^{\&infin;}{a}_{\mathrm{\&lambda;},m}{a}_{\mathrm{\&lambda;},m-1}$

Like that, provide by Lebesgue frequency spectrum expansion coefficient.

This correlation function equals by ergodic

<B(x)B(F ¹(x))

Time average

lim _N-∞(1/N)∑ _n＝1N?B(x _n)B(x _n+1)

Each X _nPass through asymptotic expression

X _n+1＝F(x _n)

Generate, remove the exception initial value X of the measurement 0 on the Q but so-called this time average equals the traversal equation of space average _LSet up the back.

Now, following here hypothesis.

a _λ，m＝C(—r) ^m(m≥0)

Wherein, the constant of C right and wrong 0.Its substitution is provided in the formula of top correlation function, then obtain

<B ₀，B ₁>＝C ²(—r) ¹(1—r ^2N)/(1—r ²)

, correlation function resembles

C(1)≡<B ₀，B ₁>＝C’(—r) ¹(N→∞)

Like that, being exponential function reduces.

Like this, with regard to symbol shift amount 1, can to any r (-1＜r＜1) be freely formed have with (-r) ¹The sequence of the correlation function that reduces of mode index number function ground.

Especially as Mazzini finds, with random code (also comprising Gold sign indicating number, volume sign indicating number) is compared when being made as frequency expansion sequence, under same bit error rate, select as mentioned above z ' [1], z ' [2] ..., under the situation of z ' [N], can increase by 15% number of users in theory.

The variance of interference noise is

σ _optimal＝3 ^1/2(K—1)/(6N)

Frequency expansion sequence in, the asymptotic action of its correlation function seems most

Like that.Therefore, if prepare to have the Lebesgue frequency spectrum the traversal mechanical system and as the filter that by the above-mentioned B (x) of this Lebesgue frequency spectrum function definition, designs with regard to enough.

a _λ，m＝C(—r) ^m(m≥0)；

r＝2—3 ^1/2

The problem here be should be how form by easy realization constitute the traversal mechanical system

F (x) and

The Lebesgue frequency spectrum

{φ _λ，j} _{λ∈Λ，j∈J}

Below, the structure based on Chebyshev's mapping is described.

Now, the Chebyshev polynomials T of consideration more than 2 times _p(x) (p ≧ 2).These Chebyshev polynomials are defined as T as mentioned above _p(cos θ)=cos (p θ) is as can be known to each p value, at closed interval Q[-1,1] on distribution function

ρ(x)dx＝dx/(π(1—x ²))

Down, to integer q, the p of q ≠ p, as

∫MT(p，x)T(q，x)ρ(x)dx＝0

Such quadrature.

By these Chebyshev polynomials and distribution function, can constitute Hilbert space L ₂At this moment, Chebyshev polynomials become Hilbert space L ₂In have a complete quadrature basis.

In the above-mentioned document, disclose the mechanical system that provides by two above Chebyshevs mappings except that having ergodic, had than this also strong blended character.The invariant measure of the traversal of this moment provides by the density function ρ (x) of the above-mentioned orthogonality of definition.

According to these character, now to j ≧ 0, q (mod p) ≠ 0, as

φ _q，j＝T(qp ^j，x)

Defined function is Φ like that _{Q, j}(x).

At this moment, according to the orthogonality and the relational expression of Chebyshev polynomials self

φ _q，j(T(p，x))

＝T(qp ^j(T(p，x)))

＝T(q，p ^j+1，x)

＝φ _q，j+1

, Φ as can be known _{Q, j}(x) be the Lebesgue frequency spectrum.

Therefore, if to integer M (1 ≦ M ≦ N) as

B(x)＝∑ _j＝1 ^N(—r) ^jφ _q，j(x)

R=2-3 wherein ^1/2

Such designing filter, can constitute and has correlation function expressing of the correlation function by above-mentioned Lebesgue frequency spectrum theory then

The spreading code used of asynchronous cdma communication system.This is open by the theory of Mazzini as mentioned above, and the number of users that usually random code is made as under certain error rate of asynchronous CDMA on basis can increase by 15%.

Here, be conceived to

B(X ₁)＝∑ _j＝1 ^M(—r) ^jφ _q，j(X ₁)＝∑ _j＝1 ^M(—r) ^j

T(qp ^j，X ₁)＝∑ _j＝1 ^M(—r) ^jT(q，X _1+j)

Set up, for arbitrary integer m (1 ≦ m ≦ N-1), for

B(X _m)＝∑ _j＝1 ^M(—r) ^jφ _q，j(X _m)＝∑ _j＝1 ^M(—r) ^j

T(qp ^j，X _m)＝∑ _j＝1 ^M(—r) ^jT(q，X _m+j)。

This function B (X) is T under the situation of q=1 _q(x)=x,

B(X _m)＝∑ _j＝1 ^M(—r) ^jX _m+j

Set up.

This means and obtain by respectively with sequence X _M+1, X _M+2..., X _M+m-1, X _M+M(1 ≦ j ≦ M) offer C (-r) ^M+1-jConstant come the operation of the sum as a result after the constant times.

This does not get rid of the operation of one of primary filter as Digital Signal Processing FIR filter (FiniteImpulse Response Filter).

Thus, can constitute by the high speed of existing this FIR of DSP technology cause filter realization the present invention calculating and the equipment of low consumpting power.Below, this equipment is described.

(example of filter)

Fig. 3 is so schematic construction ideograph of the filter of formation of expression.

Filter 201 receives various spread spectrum code sequence X such as the chaotic type spread spectrum code sequence of Chebyshev ₁, X ₂, X ₃... input, as list entries.

The spread spectrum code sequence that receives is postponed the back dispensing successively by the delay circuit 202 that is connected in series.Be chip length D time of delay.That is, be time of delay

0、D、2D、3D、4D、...、(N—1)D

Therefore, constituting time of delay with chip length D is the equal difference number sequence row of tolerance.

Also can in the prime of delay circuit 202, dispose other delay circuit.At this moment, offer the time of delay that only adds other deferred mount the time of delay that is delayed sequence respectively of amplifier 203.Especially the time of delay of establishing other deferred mount also when the D, will only postpone D, 2D, 3D, 4D ..., the sequence input amplifier 203 behind the ND.

In addition, amplify by amplifier 203 and appear at delay circuit 202 spreading code each other successively.Among Fig. 3, for the regulation real constant x, magnification ratio be respectively x (-r) ¹, x (-r) ², x (-r) ³..., x (-r) ^M-1, x (-r) ^MThat is, the magnification ratio formation is the geometric ratio number sequence row of common ratio with r.

Here, r is made as by 2-3 ^1/2The forceful pulse of definition is towards situation the best of constant, although above-mentioned situation is not satisfied in strictness, as long as-1 ≦ r ≦ 1 then can be used in the spreading code generation of asynchronous cdma communication system.Especially calculating under the situation of fixed point, under this precision, can adopt near 2-3 ^1/2Value.

Signal plus after adder 204 is amplified amplifier 203, the result, as output sequence, output module random number sequence Y successively ₁, Y ₂, Y ₃....

In order to be more readily understood, ignoring output to time of delay of input and have under the situation of input of indefinite length, be followed successively by in the sequence of input ..., s _-2, s _-1, s ₀, s ₁, s ₂... situation under, FIR filter 201 is output as

…，

x(s _-N-1(—r) ^N-1+…+s _-4(—r) ²+s _-3(—r) ¹+s _-2)，

x(s _-N(—r) ^N-1+…+s _-3(—r) ²+s _-2(—r) ¹+s _-1)，

x(s _-N+1(—r) ^N-1+…+s _-2(—r) ²+s _-1(—r) ¹+s ₀)，

x(s _-N+2(—r) ^N-1+…+s _-1(—r) ²+s ₀(—r) ¹+s ₁)，

x(s _-N+3(—r) ^N-1+…+s ₀(—r) ²+s ₁(—r) ¹+s ₂)，

…

By formation like this, from the equal difference number sequence row that constitute tolerance D time of delay of a plurality of delayed sequences of delay circuit 202 output, corresponding magnification ratio constitute common ratio be (-r) or common ratio (-1/r) geometric ratio number sequence is listed as.

These delay circuits 202, amplifier 203, adder 204 all can be made of the simple calculations circuit.Therefore, can use a computer and carry out computing, also can use ASIC, DSP, FPGA etc. to constitute the laggard row operation of specialized hardware according to software.

In addition, the effective wiring delay circuit 202 of this example constitutes with amplifier 203, but for example if will

The delay circuit of time of delay 0 and magnification ratio x (-r) ⁰Amplifier,

Time of delay D delay circuit and magnification ratio x (-r) ¹Amplifier,

Time of delay D delay circuit and magnification ratio x (-r) ²Amplifier,

...

Time of delay D delay circuit and magnification ratio x (-r) ^N-1Amplifier,

Be connected in parallel on the terminal that receives list entries, will postpone result amplified and be connected in parallel on the adder, then can obtain same effect.At this moment, the built-up sequence of each delay circuit and amplifier is arbitrary all can be near adder.

(theoretical background 2)

Before getting back to, be used as under the situation of spreading code at the mess code that will use Chebyshev polynomials to generate, but cycle generated code sequence.

That is, at X _j=X _J+N+1Situation under, needn't prepare 2N-1 numerical value X ₁..., X _2N-1If N X only arranged ₁..., X _N, then can utilize and periodically come that (0 ≦ m ≦ N) calculates B (X to all m _m).Therefore, can further shorten computing time.

Chebyshev polynomials is long-pending equally, as can be known

T(p ₁，x ₁)T(p ₂，x ₂)…T(p _s，x _s)

In s dimension cube [-1,1] ^sOn become complete quadrature basis.

In the example of above-mentioned random number output device, under the situation of utilizing filter 201, according to respectively by q ₁Mod p ₁≠ 0, q ₂Mod p ₂≠ 0 ..., q _sMod p _s≠ 0 s the numeric parameter p that sets up ₁, p ₂..., p _sDetermine s regulation positive integer q ₁, q ₂..., q _sChebyshev shine upon mechanical system, to the s dimension real number value x that generates respectively ₁, x ₂..., x _sCalculating s with 1 ≦ m ≦ 2N-1 amasss

z[m]＝T(q ₁，x ₁)T(q ₂，x ₂)…T(q _s，x _s)

At this moment, by the value z[1 that calculates], z[2] ..., z[2N-1] pseudo-random number sequence of the length N that constitutes

z’[1]＝∑ _j＝1 ^M(—r) ^jz[j]；

z’[2]＝∑ _j＝1 ^M(—r) ^jz[j+1]；

z’[N]＝∑ _j＝1 ^M(—r) ^jz[j+N—1]；

Correlation function satisfy

Therefore, if be defined as 2-3 ^1/2, and make code length N long enough, then will by s tie up direct product (?) pseudo-random number sequence that forms of chaotic mechanical system is made as the theory of variance by above-mentioned Mazzini of interference noise of the asynchronous CDMA of spreading code, by

σ _optimal＝3 ^1/2(K—1)/(6N)

Expression is compared with the situation of existing asynchronous cdma communication system, can increase by 15% number of users really under same bit error rate.

In addition, (p is x) with differential homophase mapping G (x), if the relation of satisfying (homophase bit-type) is arranged to shine upon T for Chebyshev

F(p，G(x))＝G(T(p，x))

F (p, x), then this F (p x) also has with Chebyshev and shines upon equal Lebesgue frequency spectrum, and, auto-correlation function is same constitute by (-r) ¹The tangled sequence that state reduces.

(experimental result)

Below, expression fixedly pseudo-random number sequence length N, to the analog result of the error rate of number of users (User) K and piece-ups (Number of Taps) M calculating this method.The spreading code that provides (Spreding Seqyence) is Chebyshev's sign indicating number (Cebyshev), Gold sign indicating number (Gold Seq) and general random column (Random (Uniform)).In the method, use following parameter.

s＝1。

P=2 (number of times of Chebyshev Generator is equivalent to 2).

Fig. 4-Fig. 7 is at code length N=31, and Fig. 8-Figure 11 is at code length=63, and Figure 12-Figure 15 is at N=127.

The result of this method is Cebyshef+FIR, Gold Seq+FIR, the Random+FIR in the curve, relative 2-3 ^1/2Obtain.

From these analog results as can be known, under the situation of using arbitrary spreading code, compare, can under same bit error rate, guarantee to increase by 15% number of users with existing method.

In addition, as can be known opposing tabs to count the error rate of M saturated in M=2-5 left and right sides.Therefore, also as can be known the progression M of filter also be preferably about this number.

In addition, the spreading code that provides as can be known may not be to use the mess code of Chebyshev polynomials.

(particular content of output intent)

Figure 16 is the processing carried out in the output device 101 of expression pseudo-random number sequence, be the flow chart of step of the output intent of pseudo-random number sequence of the present invention.

The output device 101 receiving sequence initial values and the numeric parameter (number of times) (step S301) of pseudo-random number sequence, according to these value and above-mentioned asymptotic expression, calculate pseudo-random number sequence (step S302), the pseudo-random number sequence (step S303) after output is calculated finishes this processing.

Like this, the output intent of pseudo-random number sequence of the present invention can be carried out easily by all-purpose computer, parallel computer, portable terminal device, especially information processor such as communication terminal, game device.

In addition, use DSP or FPGA digital circuits such as (Field Programmalbe Gate Array), also can carry out the output intent of pseudo-random number sequence of the present invention easily.

(example of dispensing device)

Figure 17 is the schematic construction ideograph of expression dispensing device of the present invention.Be marked with same-sign to the key element identical with above-mentioned figure.Illustrate below with reference to Figure 17.

Dispensing device 401 possesses signal receiving part 402, sequence efferent 403, spread spectrum portion 404, signal transmission unit 405.Sequence efferent 403 possesses the output device 101 of pseudo-random number sequence, and it is controlled.

Signal receiving part 402 receives the signal that should transmit.Typical transmission signal is voice signal under the situation of portable phone or PHS.Under the situation of carrying out digital communication, be electric digital signal.Under the situation of carrying out optical communication, also can receive the signal of telecommunication by being the signal of telecommunication from converting optical signals, under the situation of the output device 101 of realizing pseudo-random number sequence by optical computer, the former state receiving optical signals.

Sequence efferent 403 makes the output device 101 of it pseudo-random number sequence that possesses receive sequence initial value and the numeric parameter (number of times) that is assigned to dispensing device 401.The output device 101 of pseudo-random number sequence as mentioned above because output pseudo-random number sequence, so these pseudo-random number sequences of sequence efferent 403 output.

The sequence initial value can distribute different values to each dispensing device 401 in advance with numeric parameter (number of times).The communication terminals of records of values in ROM (Read OnlyMemory) such as serial number, equipment number, approval number are popularized, but it is same, can in advance sequence initial value and numeric parameter (number of times) be recorded among the ROM, this dispensing device 401 always is to use identical sequence initial value and numeric parameter (number of times).In addition, also can utilize the sequence initial value of record in the multiple ROM of being used for and numeric parameter (number of times), select the method for these values when communicating by letter at random at every turn.

Under the situation that adopts this example, the receiving system of communicating by letter with dispensing device 401 must be by knowing sequence initial value and the numeric parameter (number of times) that writes down in the ROM someway, but become under a pair of situation example that can adopt shared identical sequence initial value and numeric parameter (number of times) to write down at receiving system and receiving system.

Under the situation that a plurality of sequence initial values and numeric parameter (number of times) kind are arranged, dispensing device 401 can use one of them or call by correlation detection described later.In addition, also can use the chaotic random number sequence that obtains by asymptotic expression, prepare a plurality of sequence initial values based on Chebyshev polynomials.And as described later, can use the method for public key encryption, share sequence initial value and numeric parameter (number of times) safely by dispensing device 401 and receiving system.

The key element of the pseudo-random number sequence of sequence efferent 403 outputs be multiply by successively in spread spectrum portion 404 in the transmission signal that signal receiving part 402 receives, carry out Direct-Spread.Here, the method for the signal value of general moment t as s (t), [the sequence key element be multiply by signal s (t) successively] is described.

Under the situation of the key element of the sequence of using length N, according to the chip length w of this key element and Direct-Spread, the cycle of [the sequence key element be multiply by signal s (t) successively] becomes Nw.

From regulation moment t ₀Beginning under the situation of [the sequence key element being multiply by successively signal s (t)], comes discrete signal s (t) with the chip length w that obtains necessary quality.For example, consider to each chip length w obtain signal s (t) value method or obtain the average method etc. of the value of the signal s (t) between chip length w.Here, in order to offer some clarification on, use the former method to illustrate.

Chip length w need become can be in the receiving system side with the quality of necessity length of the information that transmits signal of fully decoding, but can select suitable chip length by known method.

In addition, if select suitable chip length w, then by only this chip length constantly w export signal train after discrete successively, from initial transmission signal, can obtain the good signal of quality.

Signal after discrete can be listed as with following number sequence and show.

s(t ₀)、s(t ₀+w)、s(t ₀+2w)、s(t ₀+3w)、s(t ₀+4w)、...

This for integer i (0 ≦ i), can put in order and be

s _I＝s(t ₀+iw)。

In the average method of the value that adopts the signal s (t) between chip length w, the as follows arrangement in order.

$s_i=(1/w){\&Integral;}_0^{w}s({\mathrm{<figure-callout\; id="0"\; label="t"\; filenames="A200810166113E00351.png,A200810166113E00371.png"\; state="\{\{state\}\}">t</figure-callout>}}_0+\mathrm{iu})\mathrm{du}$

These signal trains s _i(0 ≦ i) is that quality with necessity disperses and transmits signal train behind the signal.

With the signal train behind this signal train Direct-Spread as

s ₀z’[1]、s ₁z’[2]、...、s _N-1z’[N]、s _Nz’[1]、s _N+1z’[2]、...

Shown in.

That is, for integer i (0 ≦ i), s _i* z ' [(i mod N)+1] is the general term of these number sequence row.Here, the remainder after x mod y represents to use x divided by y.

By only sending the key element of this signal train respectively, can identical time span send the transmission signal of the stipulated time length that receives with time of chip length.

The state that Direct-Spread shown in Figure 18 is handled.The transmission signal 501 that receives for signal receiving part 402, the key element of the pseudo-random number sequence 502 by multiply by 403 outputs of sequence efferent repeatedly obtains the signal 503 of spread spectrum portion 404 outputs.

Signal transmission unit 405 sends the signal 503 of spread spectrum portion 404 outputs.For example under the situation of portable phone or PHS, send, under the situation of computer communication network, send through wired telephone line or wire/wireless LAN circuit or through optical cable through antenna.

(example of receiving system)

Receiving system of the present invention is the same with above-mentioned dispensing device, uses the output device of above-mentioned pseudo-random number sequence, obtains pseudo-random number sequence, and these number sequence row are used as the spreading code that the direct inverse spread spectrum is used.Figure 19 is the schematic construction ideograph of expression receiving system of the present invention.Below, describe with reference to Figure 19.

Receiving system 601 possesses signal receiving part 602, sequence efferent 604 and contrary spread spectrum portion 605.

Signal receiving part 602 receives the signal that is sent by above-mentioned dispensing device 401.Signal receiving part 602 is for example by realizing the interface of antenna, telephone line or lightguide cable link etc.

In the signal that signal receiving part 602 receives, comprise signal or noise that communication counterpart dispensing device 401 in addition sends.In order to remove the signal that these are not wanted, the dispensing device 401 of communication counterpart use with Direct-Spread in the identical pseudo-random number sequence of pseudo-random number sequence used.Sequence efferent 604 is accepted sequence initial value and the numeric parameter (number of times) that the dispensing device 401 of communication counterpart uses by the output device 101 that makes above-mentioned pseudo-random number sequence, exports this pseudo-random number sequence.Therefore, the example of the sequence efferent 604 of receiving system 601 is the same with the sequence efferent 403 of dispensing device 401.

In the transmission signal that the dispensing device 401 of decoding communication counterpart receives, also the signal that can send the dispensing device 401 of communication counterpart multiply by the inverse of the key element of pseudo-random number sequence successively, carries out the direct inverse spread spectrum.

If get synchronously, then contrary spread spectrum portion 605 is by to the signal train that receives

s ₀z’[1]、s ₁z’[2]、...、s _N-1z’[N]、s _Nz’[1]、s _N+1z’[2]、...

Multiply by the inverse of the key element of pseudo-random number sequence successively

1/z’[1]、1/z’[2]、...、1/z’[N]

Obtain transmitting the signal train of the information of signal with necessary quality decoded

s ₀、s ₁、...、s _N-1、s _N、s _N+1、...

。If only export this signal train successively respectively, then transmit signal and can necessary quality restore with chip length time w.

Synchronously, except that correlation detection described later, also consider to share the whole bag of tricks such as method of clock, these examples are also contained in the scope of the present invention.

As follows, use the method for the public key encryption that in dispensing device 401 and receiving system 601, communicates, the generating unit 611 of receiving system can generate sequence initial value and the numeric parameter (number of times) identical with dispensing device 401.

At first, receiving system 601 generation public-key cryptography and privacy key are right.Then, receiving system 601 sends public-key cryptography to dispensing device 401.Sequence initial value and numeric parameter (number of times) that dispensing device 401 usefulness the disclosure secret key encryptions oneself are used send to receiving system 601.The password that the decoding of receiving system 601 usefulness privacy keys sends obtains sequence initial value and numeric parameter (number of times).

As the method for this public key encryption, can use inventor of the present invention to be willing to disclosed chaotic encryption the in flat 11-No. 152063 the spy.

(other example of spread spectrum, contrary spread spectrum)

Except that above-mentioned example, when spread spectrum, contrary spread spectrum, also can adopt following example.That is, consider to want to transmit the following information data that adopts+1 or-1 value respectively.

b ₁、b ₁、b ₃、...

In the dispensing device 401, to this sequence pseudo-random number sequence that multiply by as follows successively.

b ₁z’[1]、b ₁z’[2]、...、b ₁z’[N]、

b ₂z’[1]、b ₂z’[2]、...、b ₂z’[N]、

b ₃z’[1]、b ₃z’[2]、...、b ₃z’[N]、...

Dispensing device 401 transmits the signal of finishing spread spectrum.

In addition, the signal that receives of receiving system 601 is as follows.

s ₁，s ₂，…，s _N，

s _N+1，s _N+2，…，s _2N，

s _2N+1，s _2N+2，…，s _3N，

Receiving system 601 multiply by pseudo-random number sequence successively to it, every N get and.That is following carrying out, against spread spectrum.

e ₁＝s ₁z’[1]+s ₂z’[2]+…+s _Nz’[N]，

e ₂＝s _N+1z’[1]+s _N+2z’[2]+…+s _2Nz’[N]，

e ₂＝s _2N+1z’[1]+s _2N+2z’[2]+…+s _3Nz’[N]，…

The sequence that so obtains is the information data after restoring.

In the method, send initial information data b from dispensing device 401 ₁, b ₁, b ₃... the data of N times of number.Receiving system 601 is with the information data e that restores ₁, e ₁, e ₃... number become the 1/N of the data number that receives.Therefore, be w if establish the chip length of the signal that sends and receive, the chip length of the information data after then initial information data and the recovery becomes Nw.

Aforementioned calculation is equivalent to inner product, but because spreading code is orthogonal, so by getting inner product, can be with the amplitude vanishing of other user's transmission signal.Therefore, can only obtain necessary signal.

The example of correlation detection

Dispensing device 401 is being selected any and is being carried out under the situation of Direct-Spread from a plurality of pseudo-random number sequences, receiving system 601 can be learnt the pseudo-random number sequence of choosing by correlation detection.In addition, by correlation detection, can obtain that the direct inverse spread spectrum uses synchronously.

Below, the example that carries out the receiving system under the correlation detection situation is described with reference to Figure 20.Among Figure 20, be marked with same-sign to the key element identical with key element shown in the above-mentioned figure.

Receiving system 601 also possesses generating unit 611 and correlation detection portion 612 except that signal receiving part 602, sequence efferent 603 and contrary spread spectrum portion 605.

Generating unit 611 outputs can be by the sequence initial value of dispensing device 411 selections and the group of numeric parameter (number of times).Also can only export 1 pseudo-random number sequence.At this moment, correlation detection portion 612 is owing to selecting wantonly 1 group, so be used to obtain signal Synchronization from the group of a plurality of sequence initial values and numeric parameter (number of times).

Sequence efferent 604 is exported dispensing device 411 selectable pseudo-random number sequences respectively corresponding to sequence initial value and numeric parameter (number of times) that generating unit 611 generates.

Each pseudo-random number sequence of 612 pairs of sequence efferents of correlation detection portion, 604 outputs is attempted correlation detection.Key element by the pseudo-random number sequence that will want to call multiply by the signal that receives successively, carries out correlation detection.The method of correlation detection can be used known method.

The correlation properties of the pseudo-random number sequence of using in this example are good, thus select under the situation of different pseudo-random number sequences at receiving system 601, a little less than the signal strength signal intensity behind the multiplication becomes extremely, the correlation detection failure.

In addition, be listed as under the situation of the line correlation detection of going forward side by side in the number sequence of selection with the pseudo-random number sequence of dispensing device 401, the signal strength signal intensity behind the multiplication surpasses setting.In addition, side-play amount that can mobile pseudo-random number sequence obtains signal Synchronization, with synchronous with received signal.

[inverse of key element] that is synchronized with this pseudo-random number sequence that receives signal after correlation detection portion 612 is selected be multiply by successively in contrary spread spectrum portion 605 in the signal that signal receiving part 602 receives, decoding transmits signal.

For the signal that receives, the key element of pseudo-random number sequence be multiply by successively in correlation detection portion 612, and on the contrary, [inverse of key element] of pseudo-random number sequence be multiply by successively in contrary spread spectrum portion 605.Among the former, calculate auto-correlation, cross-correlation, on the contrary, among the latter, decode.

(communication system)

The communication system of this example can be made of the above-mentioned receiving system 601 of decoding transmission signal behind the signal of above-mentioned dispensing device 401 and transmission and reception apparatus 401 transmissions.In these dispensing devices 401 and receiving system 601, if the pseudo-random number sequence difference of using, the decoding failure that then transmits signal.

Therefore, even a plurality of dispensing device 401 communicates with identical frequency band with a plurality of receiving systems 601, also can be when keeping latent words property, assurance, communicates amount of mass each other corresponding to the correspondent who is using.

Especially the pseudo-random number sequence that generates of this example is compared with existing pseudo-random number sequence, can increase considerably the kind of sign indicating number, so be suitable for comprising potentially the communication of a plurality of users' CDMA mode.

(receiving the receiving system of the signal of asynchronous transmission)

Base station in the mobile communication begins communication between the two by from the asynchronous transmission signal of portable terminal.Below, illustrate the present invention is applicable to example in the receiving system of this base station.Figure 21 is the schematic construction ideograph of the receiving system of this example of expression.

Receiving system 2101 is through antenna 2102 received signals.The signal that receives is accepted the processing from the RF frequency band transformation to the base band frequency band by band pass filter (BPF) 2103, sends to receiver side filter 2104.

In addition, sign indicating number generating unit 2111 generates the sign indicating number that is contained in the orthogonal code sequence.In orthogonal code sequence, following sequence is for example arranged.

The M sequence

The Gold sign indicating number

The orthogonal code sequence (Walsh=hadamard sequence) that obtains from walsh function

The orthogonal code sequence that obtains from Chebyshev polynomials

The Bake sequence

The Manchester's code orthogonal sequence

And, in the cdma communication technology, use plural spreading code to carry out the signal processing of spread spectrum, contrary spread spectrum.Therefore, at this moment, in real part and imaginary part, generation distributes the plural number behind the sign indicating number that comprises in these orthogonal code sequence, as sign indicating number.

The sign indicating number that generates is sent to yard side filter 2112.

Here, in receiver side filter 2104 and sign indicating number side filter 2112,, utilize to have the filter of identical parameters D, x, r, N, but preferably establish r=2-3 as above-mentioned FIR shown in Figure 3 (Finit Impulse Response) filter 201 ^1/2

The signal that correlation detection portion 2108 correlation detections were handled by receiver side filter 2104 and transmitter side filter 2112.Plural number relevant common labour by the arbitrary plural number of employing each other, calculating obtains with amassing of other plural number.

Spreading code by making mobile radio station is identical with the contrary spreading code of base station, and the result of suitably contrary this correlation detection of spread spectrum etc. obtain transmitting signal.

In the base station in mobile communication,, begin communication between the two by from the asynchronous transmission signal of portable terminal.Therefore, correlation detection is very important to the reduction of BER.In addition, under the situation of the communication from the base station to the mobile radio station (Down Link communication), because obtain in advance synchronously, so may not use present technique.

This example is characterised in that, if be only applicable to base station side (receiver side), then is enough to improve BER, in addition, has popularized the portable terminal that utilizes and can follow the former state utilization.

Figure 22 is the graph of simulation results that expression is suitable for the relation of W-cdma system under the situation of present technique and number of users in existing W-cdma system and BER.Below, illustrate with reference to Figure 22.

Among Figure 22, transverse axis is a number of users, and the longitudinal axis is BER, and the situation (LSF among the figure (BS)) of suitable present technique and the result of the situation (the W/O LSF among the figure) of prior art are shown.

For example under number of users was 20 situation, in the prior art, BER was about 0.005, and on the contrary, in present technique, BER is about 0.003, and BER obviously improves as can be known.When under identical BER, considering, in present technique, only, compared with prior art, number of users can be improved 1 one-tenth～2 one-tenth by implement the Filtering Processing of present technique in base station side.

Especially, because only by using easy GIR filter of the present invention, just can will have the W of same subscriber capacity-CDMA with 1 one-tenths～2 one-tenth of the facility cost cutting of base station, so especially when promotion W-cdma system universal, this example is very effective.

(complex filter)

Figure 23 is the best example of expression complex filter of the present invention, and especially expression is suitable for the schematic construction ideograph of filter of the mobile phone etc. of W-CDMA bill.

The filter 3101 of this example uses the pulse constant r of regulation and constant D time of delay of regulation, and the Filtering Processing sequence of complex numbers possesses input acceptance division 3102, real handling part 3103, empty handling part 3104 and efferent 3105.

At first, input acceptance division 3102 receives the input of the sequence of plural number.

Then, 3103 outputs of real handling part receive in the sequence of complex numbers after the input, the sequence of real part are received sequence after the back output Filtering Processing as input by input acceptance division 3102.

In addition, carry out the sequence after the Filtering Processing after 3104 outputs of empty handling part receive in the sequence of complex numbers after the input, the sequence of imaginary part is received as input by input acceptance division 3102.

But the processing executed in parallel of carrying out in real handling part 3103 and the empty handling part 3104.

Efferent 3105 output will be made as real part by the sequence of real handling part 3103 outputs, will be made as the sequence of complex numbers of imaginary part by the sequence of empty filtering portion output.

Here, real handling part 3103 and empty handling part 3104 are exported a plurality of sequences after the sequence delays that makes input, amplify these a plurality of sequences respectively, export the summation of the sequence after this amplification, constitute the equal difference number sequence row of tolerance D the time of delay of these a plurality of sequences, corresponding magnification ratio constitutes the geometric ratio number sequence row of common ratio-r or common ratio-1/r.

Here, real handling part 3103 and empty handling part 3104 are above-mentioned FIR shown in Figure 3 (FinitImpulse Response) filters 201, use identical parameters D, r, x, N.Use two FIR filters 201, respectively the real part and the imaginary part of Filtering Processing sequence of complex numbers.

(band spectrum modulation device)

Figure 24 is that expression uses above-mentioned filter 3101 to carry out the schematic construction ideograph of W-CDMA with the band spectrum modulation device of band spectrum modulation processing.

Band spectrum modulation device 3301 possesses scrambling portion 3302 and modulation portion 3303.

Here, 3302 outputs of scrambling portion are by the real part of the digital complex numbers of the regulation spreading code scrambling input of chip rate 1/D and the plural number behind the imaginary part.

This example is to be used for W-CDMA, so in scrambling, be suitable for system, but under the situation of using other wireless communication system (CDMA2000 system standard, WLAN IEEE802.11b etc.), be fit to the scrambling of this system according to IMT 2000W-cdma system standard.

Make this real part combine the example that carries out scrambling with imaginary part shown in Figure 23.In the embodiment of Figure 23, be 2 with length ²⁵-1 Gold sign indicating number scrambling becomes the scrambling code.By each bit of the M sequence that generates the generator polynomial from two kinds of 25 limited body GF (2) is obtained XOR or, generate this Gold sign indicating number.

In addition, as H.Holma and A.Toskala, " W-CDMA for UTMS " (John Wileyand Son, 2001) or 3rd Generation Partnership Project (3GPP); TechnicalSpecification Group Radio Access Network; Shown in the Spreading and Module (FDD) (3GTS 25.213), under W-CDMA standard, to generate the scrambling code 3.84M chip/second.

Many bit informations after the scrambling shine upon the row that (SM) is transformed to bit column or bit column by mark, with they inputs as sequence of complex numbers, offer the filter 3101 in the modulation portion 3303.The output of the filter 3101 in the modulation portion 3303 becomes the output of band spectrum modulation device 3301.

In this spreading code, can make one of the scrambling Gold of scrambling portion sign indicating number, Bake sequence or Walsh=Adama, as spreading code.

In addition, in this spreading code, also can provide spreading code at track each point with ergodic mapping mechanical system.As having ergodic mapping mechanical system, for example a the Chebyshev polynomials Fa () more than 2 times is made as mapping.

In addition, modulation portion 3303 will offer above-mentioned filter 3101 as input by the plural number of scrambling portion 3302 outputs, carry out band spectrum modulation.As mentioned above, the parameter of the time of delay of the FIR filter 201 that uses of the chip length of the digital signal of input and modulation portion 3303 all equals D time of delay that stipulates.

(experimental result)

Below, the result that the characteristics of signals to the characteristic of the filter 3101 that uses in the above-mentioned example and transmission experimentizes is described.

Figure 25 is that (transverse axis is frequency 0MHz-5MHz, and the longitudinal axis is intensity-90db-10db) for the curve of the frequency characteristic of expression filter 3101.Figure 26 is expression, and (transverse axis is frequency 0Hz-0.5Hz, and the longitudinal axis is intensity-120db-10db) by the curve of the spectrum distribution of the signal of above-mentioned band spectrum modulation device 301 transmissions.

As shown in figure 25, when the frequency spectrum of filter 3101 was 0MHz-5MHz in frequency, intensity became-2db-2db.As shown in figure 26, the frequency spectrum after the band spectrum modulation is when frequency 0Hz-0.1Hz and 0.4Hz-0.5Hz, and intensity is the mountain valley shape, step-down, but in the scope of 0.15Hz-0.35Hz, intensity illustrates smooth spectral shape.

At this moment, the frequency characteristic of filter 3101 is identical with the filter that whole frequency band is passed through (all passfilter), and filter 3101 does not influence the spectrum distribution of the signal of transmission as can be known.

In addition, establishing transfer rate is that 60kbps, user are 15 people, WWGN channel E ₀/ N ₀Be 10db, constitute W-cdma system, experimentize.At this moment, under the situation of existing method, the error rate is 0.0012, on the contrary, according to this example, is 0.00075.Therefore, the error rate reduces to 6 one-tenth approximately, and the validity of this example is shown.

Therefore, this example is being applicable under the situation of radio communication, even a plurality of dispensing device communicates with identical frequency band with a plurality of receiving systems, also can guarantee latent words property, simultaneously, can guarantee to communicate with one another corresponding to correspondent's amount of mass of using.

Utilizability on the industry

As mentioned above, according to the present invention, can provide a kind of all-purpose filter, reception The output device of device, dispensing device, band spectrum modulation device, pseudo-random number sequence, filtering method, The output intent of method of reseptance, sending method, spread spectrum modulation technique, pseudo-random number sequence reaches and is calculating Realize their program on the machine.

The spy who the present invention is based on March 26 calendar year 2001 application be willing to 2001-No. 087480, the spy of application on October 2 calendar year 2001 is willing to 2001-No. 306794 and the spy of application on February 21 calendar year 2001 is willing to 2002-No. 045255, comprises its specification, claims, accompanying drawing and summary.The open conduct of above-mentioned application is quoted as proof, and integral body is contained in this specification.

Claims (4)

1, a kind of receiving system is characterized in that: possess

Signal receiving part (201), received signal;

Receiver side filtering portion (2104) receives the described signal that receives as list entries, it is carried out exporting after the Filtering Processing;

Sign indicating number generating unit (2111) generates spreading code;

Sign indicating number side filtering portion (2112) receives the spreading code of described generation as list entries, it is carried out exporting after the Filtering Processing; With

Correlation detection portion (2108) carries out correlation detection with the result of the Filtering Processing of the described relatively sign indicating number of the result side filtering portion of the Filtering Processing of described receiver side filtering portion, obtains transmitting signal,

Described receiver side filtering portion (2104) and described sign indicating number side filtering portion (2108) all are to the time of delay constant D and the filter (201) of the positive integer M of regulation (M〉1) of regulation forceful pulse towards constant r (-1＜r＜1), regulation real constant x (x ≠ 0), regulation, possess

Input terminal is accepted the input of input signal;

Postpone the enlarging section, output will be accepted the input signal of described input respectively

With t time of delay ₀, magnification ratio a ₀Signal after postponing to amplify,

With t time of delay ₁, magnification ratio a ₁Signal after postponing to amplify,

..、

With t time of delay _M-1, magnification ratio a _M-1Signal after postponing to amplify

M signal;

Addition portion (204) exports the summation that M signal of back output amplified in described delay; With

Lead-out terminal is exported the signal of exporting after the described addition,

Wherein,

t ₀, t ₁..., t _M-1Constitute the equal difference number sequence row of tolerance D,

a ₀, a ₁..., a _M-1To constitute first be x, common ratio for-r or-the geometric ratio number sequence row of 1/r.

2, receiving system according to claim 1 (2102) is characterized in that:

The multiple orthogonal code sequence that described sign indicating number generating unit generates orthogonal code sequence or is made of real part and the different respectively orthogonal code sequence of imaginary part, as spreading code,

The orthogonal code sequence that described orthogonal code sequence comprises M sequence, Gold sign indicating number, obtain from walsh function, the orthogonal code sequence, Bake sequence, the Manchester's code orthogonal sequence that obtain from Chebyshev polynomials.

3, a kind of method of reseptance is characterized in that: possess

The signal receiving step, received signal;

The receiver side filter step receives the described signal that receives as list entries, it is carried out exporting after the Filtering Processing;

Sign indicating number generates step, generates spreading code;

Sign indicating number side filter step receives the spreading code of described generation as list entries, it is carried out exporting after the Filtering Processing; With

The correlation detection step is carried out correlation detection with the result of the Filtering Processing of described receiver side filter step with respect to the result of the Filtering Processing of described sign indicating number side filter step, obtains transmitting signal,

Described receiver side filter step and described sign indicating number side filter step all are to the time of delay constant D and the filtering method of the positive integer M of regulation (M〉1) of regulation forceful pulse towards constant r (-1＜r＜1), regulation real constant x (x ≠ 0), regulation, possess

Input step is accepted the input of input signal;

Postpone amplification procedure, output will be accepted the input signal of described input respectively

With t time of delay ₀, magnification ratio a ₀Signal after postponing to amplify,

With t time of delay ₁, magnification ratio a ₁Signal after postponing to amplify,

..、

With t time of delay _M-1, magnification ratio a _M-1Signal after postponing to amplify

M signal;

Addition step (204) is exported the summation that M signal of back output amplified in described delay; With

The output step is exported the signal of exporting after the described addition,

Wherein,

t ₀, t ₁..., t _M-1Constitute the equal difference number sequence row of tolerance D,

a ₀, a ₁..., a _M-1To constitute first be x, common ratio for-r or-the geometric ratio number sequence row of 1/r.

4, method of reseptance according to claim 3 is characterized in that:

Described sign indicating number generates in the step, the multiple orthogonal code sequence that generates orthogonal code sequence or constitute by real part and the different respectively orthogonal code sequence of imaginary part, and as spreading code,

The orthogonal code sequence that described orthogonal code sequence comprises M sequence, Gold sign indicating number, obtain from walsh function, the orthogonal code sequence, Bake sequence, the Manchester's code orthogonal sequence that obtain from Chebyshev polynomials.

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