CN101778064B - Transmitter for processing peak to average power ratio and method thereof - Google Patents

Abstract

The invention discloses a transmitter for processing a peak to average power ratio and a method thereof, which can be applied to communication systems based on orthogonal frequency division multiplexing or other multi-carriers. The transmitter uses N subcarriers, wherein L subcarriers are maintained and used for reducing a signal peak to average power ratio, and L is smaller than N. The method comprises the following steps of: after data characters of an original frequency domain are generated, sending the data characters into a maintained subcarier character generator, wherein the maintained subcarriers can be generated through the signal processing of a simple frequency domain; combining the generated maintained subcarrier characters and the original data characters to obtain a transmission signal with a reduced peak to average power ratio, repeatedly sending the transmission signal with the reduced peak to average power ratio into the maintained subcarrier character generator to generate updated maintained subcarrier characters; and after several repeated processing, combining the original data characters with the maintained subcarrier characters so as to obtain a transmission signal with a minimum peak to average power ratio.

Description

The conveyer of processing power peak to average and method thereof

Technical field

The invention relates to a kind of conveyer and obtain the method for peak to average power ratio, and particularly relevant for a kind of conveyer and method thereof that is used to frequency domain processing power peak to average.

Background technology

At orthogonal frequency division multiplex (MUX) (Orthogonal frequency division multiplexing, OFDM) in communication system, excessive signal power peak to average (peak-to-average power ratio, PAPR) will reduce the signal quality that transmits or have influence on the delivering power efficient of conveyer.This is former because conveyer has nonlinear radio frequency (Radio frequency, RF) front-end circuit, for example power amplifier usually.Fig. 1 is a kind of input power Pin of power amplifier and the graph of relation of power output Pout.When the power peak of input power Pin arrived inelastic region NL, the output signal of power amplifier will be lost genuine phenomenon generation and reduce the signal quality that transmits.Make its range of linearity that falls within power amplifier if reduce input power Pin, can lower the efficient of delivering power.

In the middle of multicarrier (Multi-carrier) transmission system, the for example many accesses of the orthogonal frequency division of IEEE 802.16e standard (Orthogonal Frequency-Division Multiple Access, OFDMA) in pattern, base station (Base-station, BS) can keep some subcarriers (sub-carrier), and reduce the excessive phenomenon of above-mentioned PAPR with these subcarriers.Please refer to Fig. 2, its diagram is the schematic diagram of the method for traditional a kind of PAPR of minimizing.X (t) is the signal original to be transmitted of time domain (time-domain).As seen from Figure 2, signal x (t) original to be transmitted has two peak values (peak) that surpass critical value TH.In traditional method, be the subcarrier that passes through to keep, produce peak value and reduce signal P (t), and P (t) is circled round respectively translation (cyclic shift) to time point ni and nj on time shaft, produce respectively signal P _ni(t) and P _nj(t).With P _ni(t) and P _nj(t) be multiplied by respectively phase parameter and amplitude parameter, i.e. β _iWith μ _iAnd β _jAnd μ _jAfterwards, then with signal x (t) addition, can obtain the number of delivering letters x ' revised to be passed that power peak reduces (t).

Yet, in traditional method, must to have at least two anti-Fu Li leaf conversion (Inverse FastFourier transform, IFFT) circuit to produce respectively signal x (t) and P (t).And, (t) can possess desired low-power peak to average effect in order to make the number of delivering letters x ' to be passed, traditional method usually need to signal carry out more than four times cross sampling (over-sampling) after, then carry out the processing of above-mentioned reduction PAPR.

Summary of the invention

In view of this, one example of the present invention by processing, can not need a plurality of anti-Fu Li leaf conversions, and the action that need not carry out taking a sample can be reached for a kind of conveyer and method thereof are provided in frequency domain.

According to another example of the present invention, be applied in the conveyer of an OFDM communication system.Conveyer is to use N subcarrier, and L subcarrier in N subcarrier is the subcarrier that is retained, and L is less than N.The method comprises the following steps: to receive a data-signal, and the package power of data-signal can be disassembled into a constant power and a power of disturbance.Generation is positioned at L reservation subcarrier symbol of L the subcarrier that is retained subcarrier.Upgrade L according to data-signal and keep the subcarrier symbol, and produce according to this a signal to be combined.In frequency domain, signal to be combined is combined with data-signal.

According to a further aspect in the invention, propose a kind of conveyer, be applied in an orthogonal frequency division multiplex (MUX) communication system.Conveyer is to use N subcarrier, and L subcarrier in N subcarrier is the subcarrier that is retained, and L is less than N.This conveyer comprises that a modulation unit, keeps subcarrier symbol generation unit and a merge cells.The modulation unit is in order to export a data-signal, and the package power of data-signal has a constant power and a power of disturbance.Keep subcarrier symbol generation unit and be positioned at L L reservation subcarrier symbol that is retained on sub-carrier positions in order to generation, upgrade L according to data-signal and keep the subcarrier symbol, and produce according to this a signal to be combined.Merge cells is used to frequency domain signal to be combined is combined with data-signal.

For foregoing of the present invention can be become apparent, a plurality of embodiment cited below particularly, and coordinate appended graphicly, be described in detail below.

Description of drawings

Fig. 1 illustrates a kind of input power Pin of power amplifier and the graph of relation of power output Pout.

Fig. 2 illustrates the schematic diagram of the method that is traditional a kind of PAPR of minimizing.

Fig. 3 illustrates the calcspar of a kind of conveyer in order to the peak to average power ratio that reduces data-signal that is one embodiment of the invention.

Fig. 4 shows that the number that hypothesis is retained subcarrier is 3, is X and keep the subcarrier symbol _a, X _b, and X _cThe time || ρ || ²One example of value.

Fig. 5 illustrates the analog result figure of the embodiment that is Fig. 3.

Fig. 6 illustrates the calcspar of a kind of conveyer in order to the peak to average power ratio that reduces data-signal that is another embodiment of the present invention.

Fig. 7 illustrates the analog result figure of the embodiment that is Fig. 6.

Fig. 8 illustrates the more calcspar of the conveyer of another embodiment of the present invention.

[main element symbol description]

300,600,800: conveyer

302,602: the modulation unit

304,604,804: keep subcarrier symbol generation unit

306,606,806: merge cells

308,608,808: converting unit

310,610: keep sub-carrier indices value generator

312: switch

502,504,506,508,702,704,706: curve

612,614: switch

816: filter

818: the first multipliers

820: the second multipliers

Embodiment

The present invention proposes a kind of method that obtains peak to average power ratio, is applied in a conveyer of a multicarrier (Multicarrier) transmission system.Conveyer is to use N subcarrier, and L subcarrier in N subcarrier is to be retained subcarrier, and L is less than N, and the method comprises the following steps.Receive a data-signal, the package power of data-signal has a constant power and a power of disturbance.Generation is positioned at L the subcarrier symbol that is retained on subcarrier.Upgrade L subcarrier symbol according to data-signal, and produce according to this a signal to be combined.Merge signal to be combined in data-signal in frequency domain, so that the corresponding power of disturbance of data-signal after upgrading diminishes, thereby reduce the peak to average power ratio of signal transmission.The below is described in detail as follows further for an embodiment.

Please refer to Fig. 3, its diagram is the calcspar of a kind of conveyer in order to the peak to average power ratio that reduces data-signal of one embodiment of the invention.Above-mentioned multicarrier transmission systems is for example the OFDM communication system.Conveyer 300 comprises that a modulation unit 302, keeps subcarrier symbol generation unit 304, an and merge cells 306.Modulation unit 302 is in order to export a data-signal Data, and the power of data-signal Data has a constant power and a power of disturbance.Keep subcarrier symbol generation unit 304 and be positioned at L the reservation subcarrier symbol that is retained subcarrier in order to generation, upgrade L according to data-signal Data and keep the subcarrier symbol, and produce according to this a signal Cmb to be combined.Merge cells 306 is used to frequency domain in conjunction with signal Cmb to be combined and data-signal Data, so that the corresponding power of disturbance of data-signal Data ' after adjusting diminishes, thereby reduces the peak to average power ratio of signal transmission.

Furthermore, the sub-carrier indices value of supposing N the subcarrier that conveyer 300 uses is 0 to N-1, and the set of the L that is retained subcarrier sub-carrier indices value in N subcarrier is U, U={k ₀, k ₁... k _L-1.Data-signal Data has N the data symbol X that is positioned at N subcarrier ₀, X ₁..., X _N-1Definition data vector X=[X ₀, X ₁... X _N-1] ^T, X _iBe i data symbol, i is 0 to N-1 integer.Disturb in order to make signal transmission do not kept the subcarrier symbol, before our tentation data not yet merges with reservation subcarrier symbol, when i ∈ U, X _i=0, however the method for the peak to average power ratio of reduction data-signal of the present invention is not subject to this hypothesis.

In addition, L above-mentioned reservation subcarrier symbol of definition is

And definition reservation subcarrier symbol vector is $X_R={[X_{k_0},{\mathrm{<figure-callout\; id="1"\; label="X\; k"\; filenames="H2009100022300E00011.png,H2009100022300E00061.png"\; state="\{\{state\}\}">X</figure-callout>}}_{k_{}},...X_{k_{L-1}}]}^T.$ Suppose that above-mentioned signal Cmb to be combined has N and merges symbol C ₀, C ₁..., C _N-1, definition merges vectorial C=[C ₀, C ₁..., C _N-1] ^T, C _iBe i and merge symbol.Similarly, when $i\&NotElement;U$ Or i ∈ U ^CThe time, C _i=0, however the method for the peak to average power ratio of reduction data-signal of the present invention is not subject to this hypothesis.

The present embodiment can be illustrated by following formula (1):

Find out Make $\hat{C}=\arg \underset{C}{\min }{\left|\right|x+c\left|\right|}_{\&infin;}=\arg \underset{C}{\min }{\left|\right|F(X+C)\left|\right|}_{\&infin;}---\left(1\right)$

Wherein, x and c represent respectively data-signal Data and the signal Cmb to be combined of time domain.F represents the IFFT matrix of N * N, wherein:

${\left\{F\right\}}_{n,k}={\mathrm{<figure-callout\; id="2"\; label="e\; j"\; filenames="H2009100022300E00061.png"\; state="\{\{state\}\}">e</figure-callout>}}^j$ for?n，k＝0，1，...，N-1。

Formula (1) refers to, with all possible c and x respectively after addition, the maximum of obtaining in all elements absolute value (norm) that makes vector x+c in all c is hour c value.Such c can be so that the power peak of x+c be minimum, and makes the power peak of data-signal Data ' descend, to reduce the value of PAPR.Obtain the c that meets this condition, can reach by obtaining corresponding C.

The method that the below will try to achieve above-mentioned C is described as follows.

The time-domain signal x (t) of the data-signal Data of OFDM is defined as:

$x\left(t\right)=\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{X}_{\mathrm{<figure-callout\; id="2"\; label="k\; e\; j"\; filenames="H2009100022300E00061.png"\; state="\{\{state\}\}">k</figure-callout>}}{e}^j{2\mathrm{\&pi;}\frac{k}{N}t}^{}---\left(2\right)$

Wherein, 0≤t≤T and T represent the symbol duration (symbol duration).And the package power of signal x (t) (envelope power) is defined as:

$P_x\left(t\right){\left|\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{X}_{\mathrm{<figure-callout\; id="2"\; label="k\; e\; j"\; filenames="H2009100022300E00061.png"\; state="\{\{state\}\}">k</figure-callout>}}{e}^j{2\mathrm{\&pi;}\frac{k}{T}t}^{}\right|}^2=\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{\left|X_k\right|}^2+2\mathrm{Re}\left\{\underset{u=1}{\overset{N-1}{\mathrm{\&Sigma;}}}\mathrm{\&rho;}\left(u\right)e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100022300E00061.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}\frac{u}{T}t}\right\}---\left(3\right)$

Wherein, definition

$\mathrm{\&rho;}\left(u\right)=\underset{k=0}{\overset{N-1}{\mathrm{\&Sigma;}}}{X}_k{X}_{k+u}^{*}$ for?1≤u≤N-1

ρ (μ) is called { X _k} ₀ ^N-1Aperiodicity auto-correlation function (Aperiodic Auto-correlationFunction, AACF).

Definition (3) hereby

Be constant power,

Be disturbance (fluctuation) power.Due to Be constant power, can not change along with time t, so P _x(t) size will be by meeting along with time t changes

Size determine.Therefore, if minimize P _x(t), can be by minimizing power of disturbance

Value reach.Generally speaking, and will time dependent power of disturbance minimize and be not easy, thus we then wish AACF p-absolute value (that is to say the absolute value of p power) and

Can be the smaller the better.Wherein, p＞0 or be positive integer.

As long as can obtain one group of { X _k} ₀ ^N-1, make

Can minimizedly talk about, we just can expect that therefore power of disturbance can reduce so.Below will equal 2 as example explanation take the p value, yet the present embodiment is not limited to this.Wherein, the present embodiment is by changing { X _k} ₀ ^N-1In, correspond to the reservation subcarrier symbol that is retained subcarrier Make

Minimize.The present embodiment is that the method for suddenly falling (steepest descent) changes reservation subcarrier symbol

Value so that Minimize.

Hereby be described in detail as follows.Via calculating, can get

${\left|\right|\mathrm{\&rho;}\left(u\right)\left|\right|}^2=\underset{m=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}\underset{k=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}{X}_k{X}_m^{*}{X}_{k+u}^{*}{X}_{m+u}---\left(4\right)$

Can get after formula (4) partial differential

$\frac{\&PartialD;}{{\&PartialD;X}_{k_i}^{*}}{\left|\right|\mathrm{\&rho;}\left(u\right)\left|\right|}^2=2[X_{k_i-u}{\left(\underset{k=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}{X}_k{X}_{k+u}^{*}\right)}^{*}+X_{k_i+u}\left(\underset{k=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}{X}_k{X}_{k+u}^{*}\right)]---\left(5\right)$

I=0 wherein, 1 ..., L-1 and u+1≤k _i≤ N-u-1.

Then, definition AACF vector be ρ=[ρ (1), ρ (2) ..., ρ (N-1)] ^TThe definition ρ absolute value of a vector square (be also || ρ || ²) equal | ρ (1) | ²+ | ρ (2) | ²+ ...+| ρ (N-1) | ²(be also

).The partial differential that therefore, can obtain the AACF vector is

$\frac{\&PartialD;}{{\&PartialD;X}_{k_i}^{*}}{\left|\right|\mathrm{\&rho;}\left|\right|}^2\frac{\&PartialD;}{\&PartialD;X_{k_i}^{*}}\underset{u=1}{\overset{N-1}{\mathrm{\&Sigma;}}}{\left|\right|\mathrm{\&rho;}\left(u\right)\left|\right|}^2=2\underset{u=1}{\overset{N-1}{\mathrm{\&Sigma;}}}[X_{k_i-u}{\left(\underset{k=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}{X}_k{X}_{k+u}^{*}\right)}^{*}+X_{k_i+u}\left(\underset{k=0}{\overset{N-u-1}{\mathrm{\&Sigma;}}}{X}_k{X}_{k+u}^{*}\right)]---\left(6\right)$

In addition, definition reservation subcarrier symbol vector is $X_R=[X_{k_0},{\mathrm{<figure-callout\; id="1"\; label="X\; k"\; filenames="H2009100022300E00011.png,H2009100022300E00061.png"\; state="\{\{state\}\}">X</figure-callout>}}_{k_{}},...,X_{k_{L-1}}{]}^T.$ Above-mentioned change X _RThe method of suddenly falling for according to the absolute value of a vector of AACF vector square (|| ρ || ²) for keeping subcarrier symbol vector X _RGradient (gradient), upgrade L and keep the subcarrier symbol

For instance, can upgrade by following formula:

The present embodiment passes through recursively, and (iteratively) calculates X _R, minimize || ρ || ²N represents update times.X _R ⁽ⁿ⁺¹⁾Represent the X after renewal the n+1 time _R, X _R ⁽ⁿ⁾Represent the X before renewal the n+1 time _RThe X that the n=0 interval scale does not upgrade _R ⁽⁰⁾, for example can equal original X _R, right X _R ⁽⁰⁾Also can be other value.μ is step units (step size).

Afterwards, keeping subcarrier symbol generation unit will be according to X _R ⁽ⁿ⁺¹⁾Produce combined signal Cmb.N in combined signal Cmb merges symbol C ₀, C ₁..., C _N-1In, for symbol C _i, when i ∈ U, $C_i=X_i^{(n+1)}.$ Then, merge cells 306 will merge signal Cmb to be combined in data-signal Data in frequency domain, and produce the data-signal Data ' after adjusting.Data-signal Data ' can Y ₀, Y ₁..., Y _N-1Represent.For symbol Y _i, when i ∈ U, Y _i=C _iWhen $i\&NotElement;U$ The time, Y _i=X _iConveyer 300 has a converting unit 308, changes in order to the data-signal Data ' after merge cells 306 is processed, and transmits signal Data to produce accordingly one of time domain " to send out.Converting unit 308 is for example the IFFT transducer.

Conveyer 300 for example more comprises a switch 312, is used to recursively calculate X _RThe time, make keep subcarrier symbol generation unit 304 can be according to the data-signal Data ' after adjusting, calculate the X after renewal _RValue, and upgrade data-signal Data '.And then with the data-signal Data ' after upgrading, upgrade again X _R, until update times reaches the recurrence number of times of being scheduled to.

In addition, conveyer 300 also has one and keeps sub-carrier indices value generator 310, in order to produce the index value of the above-mentioned L that is retained a subcarrier subcarrier.Its index value that produces will be exported to and keep subcarrier symbol generation unit 304.

Hereby the physical significance with formula (7) is described as follows.Please refer to Fig. 4, the number that its demonstration hypothesis is retained subcarrier is 3, is X and keep the subcarrier symbol _a, X _b, and X _cThe time || ρ || ²One example of value.

If known X _R ⁽ⁿ⁾, the order vector $\stackrel{\&RightArrow;}{G}={\&dtri;}_{X_R}{\left|\right|\mathrm{\&rho;}\left|\right|}^2{|}_{X_R^{\left(n\right)}}.$ Due to vector Can be considered || ρ || ²The direction of value change amount maximum, therefore, foundation

Ask X _R ⁽ⁿ⁺¹⁾, resulting X _R ⁽ⁿ⁺¹⁾Will compare X _R ⁽ⁿ⁾More approaching || ρ || ²Extreme value, be for example the P point.Therefore, by finding out

Upgrade X _R, can be made || ρ || ²The value reservation subcarrier symbol X of more ordering near P _a, X _b, and X _c, and conform with required.

In addition, above-mentioned is that step units μ is the value that formula (7) can be restrained.μ follow the example of be for example can with reference to predefined one table look-up (look-up table) obtain.This tables look-up and can set according to the various communications parameters of conveyer, and these communications parameters are for example the number N of the subcarrier that uses, or the size (size) when carrying out fast fourier conversion (FFT) etc.

Please refer to Fig. 5, it illustrates is the analog result figure of the present embodiment.This simulation be take the FFT size as 1024, the number N of subcarrier that conveyer was used as 1024, be retained the number L of subcarrier as 72, the sub-carrier indices value that is retained subcarrier is that random optimization (Random optimized) is chosen, crossing sampling rate (Over-sampling Rate) is 4, zero filling (Frequency domain zero-padding) of interpolation method frequency of utilization territory, the recurrence number of times is that the setting of 4 times is simulated.

In Fig. 5, transverse axis represents PAPR, and the longitudinal axis is complementary cumulative distribution functional value (Complementary cumulative distribution function, CCDF).CCDF refer to greater than the probability of the value of the PAPR of correspondence and.The CCDF value is less, represents that the peak to average power ratio of signal transmission is less.The curve 502 of Fig. 5 and 504 is the CCDF value of original data-signal Data, curve 506 and the 508 CCDF values for the data-signal Data ' after the method for the PAPR of the reduction data-signal that carries out the present embodiment.Curve 502 and 506 was the simulation results after sampling, and curve 504 and 508 is the analog results under Nai Kuisi (Nyquist) sampling rate.As seen from Figure 5, after processing via the method for the present embodiment, the PAPR value can reduce 2dB haply, and historical facts or anecdotes has the peak to average power ratio reduction and the signal quality that make the data-signal Data ' that will transmit and improves.

Please refer to Fig. 6, it illustrates the calcspar of a kind of conveyer 600 in order to the peak to average power ratio that reduces data-signal that is another embodiment of the present invention.Different from last embodiment is that in the present embodiment, above-mentioned L keeps the subcarrier symbol and be divided into many group reservation subcarrier symbols.The present embodiment keeps in the subcarrier symbol in L of renewal, is the modes of subcarrier symbols that keep by upgrading in order this many groups, upgrades this L reservation subcarrier symbol.

In conveyer 600, switch 614 is optionally to be electrically connected with modulation unit 602 and merge cells 606, and switch 612 is optionally to be electrically connected with converting unit 608 and merge cells 606.

Keep sub-carrier indices value generator 610 output on the same group the index value of reservation subcarrier symbol not respectively in order by making, make reservation subcarrier symbol generation unit 604 only keep subcarrier symbol for certain group and upgrade, to produce combined signal Cmb_1.The subcarrier symbol is not yet upgraded complete if still with a hook at the end, switch 612 and 614 can make the data-signal Data ' that merge cells 606 exports _ 1 feedback to keeping subcarrier symbol generation unit 604, next group is kept subcarrier symbol upgrades so that keep subcarrier symbol generation unit 604.And when the reservation subcarrier symbol of all groups all upgrade complete after, switch 612 can make data-signal Data ' _ 1 export converting unit 608 to.

Please refer to Fig. 7, it illustrates is the analog result figure of the present embodiment.Curve 702 is for being divided into one group with L reservation subcarrier symbol, and the analog result of recurrence number of times when being 2 times.Curve 704 is for being divided into one group with L reservation subcarrier symbol, and the analog result of recurrence number of times when being 4 times.Curve 706 is for being divided into four groups with L reservation subcarrier symbol, and the analog result of recurrence number of times when being 4 times.Can be found out by curve 706, keep the subcarrier symbol with L and be divided into many group reservation subcarrier symbols, and upgrade in order the way that these many groups keep the subcarrier symbol, will make the signal power peak to average more reduce.

In addition, in another embodiment more of the present invention, above-mentioned L keeps the subcarrier symbol and also can be divided into many group reservation subcarrier symbols.The present embodiment keeps in the subcarrier symbol in L of renewal, is the modes of subcarrier symbols that keep by upgrading side by side this many groups, upgrades this L reservation subcarrier symbol.In processing side by side, the reservation subcarrier symbol that is untreated can be regarded non-reservation subcarrier symbol as and be processed.

Please refer to Fig. 8, it illustrates the more calcspar of the conveyer 800 of another embodiment of the present invention.Different from the embodiment of Fig. 3 is that conveyer 800 has more a filter 816, one first multiplier 818 and one second multiplier 820.Filter 816 has frequency response function H, and Hk is illustrated in the frequency response coefficient value of k subcarrier.The first multiplier 818 is in order to multiply by N data symbol respectively corresponding frequency response coefficient Hk.Reservation subcarrier symbol generation unit 804 is L the reservation subcarrier symbols of N data symbol renewal after basis multiply by Hk, and produces signal Cmb_2 to be combined.The second multiplier 820 is in order to multiply by signal Cmb_2 to be combined 1/Hk and to export merge cells 806 to.Converting unit 808 is changed in order to the data-signal Data ' after merge cells 806 is processed _ 2, to produce accordingly the transmission signal Data of time domain " _ 2, and export filter 816 to.

In this embodiment, it is the data-signal that is equivalent to through after in filter 816 places due to the data-signal of the process institute reference of upgrading L reservation subcarrier symbol, therefore, L after the renewal that produces of this embodiment keeps the subcarrier symbol and more can eliminate further the impact that filter 816 may cause for the peak value of the package power of data-signal.

Its method in order to the peak to average power ratio that reduces data-signal of the above embodiment of the present invention is to complete in frequency domain, so can not need must to carry out Fu Liye conversion repeatedly as traditional method.

In sum, although the present invention discloses as above with an embodiment, so it is not to limit the present invention.The persond having ordinary knowledge in the technical field of the present invention, without departing from the spirit and scope of the present invention, when being used for a variety of modifications and variations.Therefore, protection scope of the present invention is as the criterion when looking the scope that claim defines.

Claims (12)

1. the method in a conveyer that is applied to multicarrier transmission systems, described conveyer is to use N subcarrier, and L subcarrier in a described N subcarrier is the subcarrier that is retained, and L is characterized in that less than N, and the method comprises:

Reception of data signal, the package power of described data-signal has constant power and power of disturbance;

Generation is positioned at L reservation subcarrier symbol of L the subcarrier that is retained subcarrier;

Upgrade described L according to described data-signal and keep the subcarrier symbol, and produce according to this signal to be combined; And

Merge described signal to be combined in described data-signal in frequency domain.

2. method according to claim 1, it is characterized in that, described data-signal has N the data symbol that is positioned at N subcarrier, described N data symbol corresponded to aperiodicity auto-correlation function vector, described L keeps the subcarrier symbol and is corresponded to reservation subcarrier symbol vector, in the step of upgrading described L reservation subcarrier symbol, it is square gradient for described reservation subcarrier symbol vector according to the absolute value of a vector of described aperiodicity auto-correlation function vector, upgrade described L and keep the subcarrier symbol, or be used as upgrading according to the p power of the absolute value of a vector of described aperiodicity auto-correlation function vector, p is greater than 0.

3. method according to claim 1, is characterized in that, the described L of described renewal step that keeps the subcarrier symbol comprises that upgrading described L in the mode of recurrence keeps the subcarrier symbol.

4. method according to claim 1, it is characterized in that, described L keeps the subcarrier symbol and is divided into many group reservation subcarrier symbols, in the step of upgrading described L reservation subcarrier symbol, be the mode of subcarrier symbol that keeps by upgrading in order described many groups, upgrade described L and keep the subcarrier symbol.

5. method according to claim 1, it is characterized in that, described L keeps the subcarrier symbol and is divided into many group reservation subcarrier symbols, in the step of upgrading described L reservation subcarrier symbol, be the mode of subcarrier symbol that keeps by upgrading side by side described many groups, upgrade described L and keep the subcarrier symbol.

6. method according to claim 1, it is characterized in that, described conveyer has filter, the frequency response function of described filter is H, Hk is illustrated in the frequency response coefficient value of k subcarrier, described data-signal has N the data symbol that is positioned at N subcarrier, and the described L of described renewal step that keeps the subcarrier symbol comprises:

Described N data symbol be multiply by respectively corresponding Hk;

Upgrade described L reservation subcarrier symbol according to described N the data symbol that multiply by after Hk, and produce accordingly described signal to be combined; And

With described signal times to be combined with 1/Hk;

Wherein, the signal described to be combined that multiply by 1/Hk is as the signal described to be combined in order to merge with described data-signal in combining step.

7. a conveyer, be applied in orthogonal frequency division multiplex (MUX) communication system, and described conveyer is to use N subcarrier, and L subcarrier in a described N subcarrier is the subcarrier that is retained, and L is characterized in that less than N, and described conveyer comprises:

The modulation unit, in order to outputting data signals, the package power of described data-signal has constant power and power of disturbance;

Keep subcarrier symbol generation unit, be positioned at L reservation subcarrier symbol of L the subcarrier that is retained subcarrier in order to generation, upgrade described L according to described data-signal and keep the subcarrier symbol, and produce according to this signal to be combined;

Merge cells is used to frequency domain and merges described signal to be combined in described data-signal.

8. conveyer according to claim 7, it is characterized in that, described data-signal has N the data symbol that is positioned at N subcarrier, described N data symbol corresponded to aperiodicity auto-correlation function vector, described L keeps the subcarrier symbol and is corresponded to reservation subcarrier symbol vector, described modulation unit is square gradient for described reservation subcarrier symbol vector according to the absolute value of a vector of described aperiodicity auto-correlation function vector, upgrade described L and keep the subcarrier symbol, or be used as upgrading according to the p power of the absolute value of a vector of described aperiodicity auto-correlation function vector, p is greater than 0.

9. conveyer according to claim 7, is characterized in that, described modulation unit is to upgrade described L in the mode of recurrence to keep the subcarrier symbol.

10. conveyer according to claim 7, it is characterized in that, described L keeps the subcarrier symbol and comprises many groups and keep the subcarrier symbols, and described modulation unit is the mode of subcarrier symbols that keeps by upgrading in order described many groups, upgrades described L reservation subcarrier symbol.

11. conveyer according to claim 7, it is characterized in that, described L keeps the subcarrier symbol and comprises many groups and keep the subcarrier symbols, and described modulation unit is the mode of subcarrier symbols that keeps by upgrading side by side described many groups, upgrades described L reservation subcarrier symbol.

12. conveyer according to claim 7 is characterized in that, described data-signal has N the data symbol that is positioned at N subcarrier, and described conveyer has more:

Filter has frequency response function H, and Hk is illustrated in the frequency response coefficient value of k subcarrier;

The first multiplier, in order to described N data symbol be multiply by respectively Hk, described reservation subcarrier symbol generation unit is described L the reservation subcarrier symbol of described N data symbol renewal after basis multiply by Hk, and produces accordingly described signal to be combined;

The second multiplier, in order to described signal times to be combined with 1/Hk and export described merge cells to;

Converting unit is changed in order to the described data-signal after described merge cells is processed, and producing accordingly the transmission signal of time domain, and exports described filter to.

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