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CN101222468B - Peak-to-average ratio restraining method and device in multi-carrier orthogonal frequency division multiplexing system - Google Patents

Peak-to-average ratio restraining method and device in multi-carrier orthogonal frequency division multiplexing system Download PDF

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CN101222468B
CN101222468B CN2008100071016A CN200810007101A CN101222468B CN 101222468 B CN101222468 B CN 101222468B CN 2008100071016 A CN2008100071016 A CN 2008100071016A CN 200810007101 A CN200810007101 A CN 200810007101A CN 101222468 B CN101222468 B CN 101222468B
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channel signal
carrier wave
clipped noise
peak
transceiver combination
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CN101222468A (en
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邹志强
武杰
张彬彬
朱尔霓
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Huawei Technologies Co Ltd
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Huawei Technologies Co Ltd
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2614—Peak power aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2614—Peak power aspects
    • H04L27/2623—Reduction thereof by clipping

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Abstract

The invention discloses a method for peak-to-average ratio suppression in a multi-carrier orthogonal frequency division multiplexing OFDM system. The system comprises that: baseband frequency-domain signals of each carrier are combined into a time-domain multi-carrier combination channel signal on each OFDM symbol; clipping noise corresponding to each carrier is obtained from the multi-carrier combination channel signal, the length of the clipping noise is a symbol length; a frequency-domain response of the clipping noise corresponding to each carrier and symbol length is obtained, is reversely superposed to a baseband frequency-domain signal after the corresponding carrier has a time delay on an OFDM symbol to make a peak-to-average ratio suppression. The invention also discloses a device for peak-to-average ratio suppression in a multi-carrier OFDM system. The invention can make an effective suppression to the peak-to-average ratio in the multi-carrier OFDM system.

Description

The method and apparatus that peak-to-average force ratio suppresses in the multi-carrier orthogonal frequency division multiplexing system
Technical field
The present invention relates to OFDM (OFDM, Orthogonal Frequency DivisionMultiplexing) technology, particularly the method and apparatus that peak-to-average force ratio suppresses in the multi-carrier OFDM systems.
Background technology
In the existing communication technology, the OFDM technology is with its higher frequency efficiency, stronger anti-intersymbol interference (ISI, Inter Symbol Interference) and carrier-in-interference (ICI, Inter CarrierInterference) ability, become the key technology of the 4th third-generation mobile communication.
At single-carrier technology, transmitting terminal at ofdm signal, if single carrier includes N subcarrier, then high-speed data-flow is divided into N parallel sub data flow through string and after changing, carry out inverse Fourier transform (IFFT, Inverse Fast Fourier Transform), frequency-region signal is transformed into time domain, length be N IFFT output be the sample value symbol of N time domain, be called the OFDM symbol.For eliminating intersymbol interference, (CP CyclicPrefix), forms the OFDM symbol of a cyclic extensions can to insert Cyclic Prefix between user data.At the receiving terminal of ofdm signal, earlier the time-domain signal that receives is removed CP, carry out operations such as Fourier transform (FFT, Fast FourierTransform), digital demodulation then and correctly receive data.
When ofdm system subcarrier number increased, the peak-to-average force ratio of transmitting terminal signal (PAPR, Peakto Average Power Ratio) also can correspondingly increase.As everyone knows, the sender of wireless base station utilizes power amplifier to transmit in the mobile communication system, to compensate the signal attenuation that brings because of propagation distance.Power amplifier has certain range of linearity, and the signal with high peak-to-average force ratio can reduce the efficient of power amplifier and increase power consumption, and therefore the inhibition to peak-to-average force ratio is the problem that urgently will solve.
Further, since the appearance of the 3rd third-generation mobile communication system, for volume that reduces the base station effectively and the cost that reduces the base station, generally adopted multi-transceiver technology, promptly comprise a plurality of carrier waves in the system, each carrier wave comprises a plurality of subcarriers again.For single-carrier technology, finish the transmission of multichannel carrier information owing to can utilize a reflector and power amplifier, therefore can greatly reduce the volume and the cost of base station, but the subcarrier number in the multi-carrier OFDM systems is more, the PAPR that causes closing the channel signal behind the road is bigger, thereby suppresses to have higher requirement for the multicarrier peak-to-average force ratio.
In order to suppress the higher peak-to-average force ratio of multicarrier system, prior art has proposed a kind of slicing scheme of multistage matched filtering at multicarrier system, and Fig. 1 shows the slicing scheme theory diagram of this many matched filterings.Wherein, the formation of multi-transceiver combination time-domain signal can be briefly described into, transmission data and the control data bit of each single carrier on each symbol, encoded device is made corresponding constellation mapping according to predictive encoding scheme coding back by modulation system, with after IFFT adds CP after handling, and carry out time-domain windowed (RAMP), be filtering to high power speed time-domain signal by interpolate value behind the framing, and be modulated to add up one by one behind the different frequent points by digital controlled oscillator (NCO, Numeric Control Oscillator) and obtain the multi-transceiver combination channel signal.The multi-transceiver combination channel signal of above-mentioned formation enters slicing processing procedure shown in Figure 1, at first extract the clipped noise that is higher than predetermined threshold in the channel signal, remove the noise of being with in the clipped noise on outer part and some important subcarriers by multistage matched filtering module then, at last the multi-transceiver combination time-domain signal after the time-delay that oppositely is added to through the clipped noise of matched filtering, form the multi-transceiver combination time-domain signal behind the slicing.Adding up after the filter factor of the matched filtering is here modulated through NCO by the source filter coefficient obtains, and identical filter coefficient is all used in each grade matched filtering.
Though the scheme that above-mentioned patent provides is under the condition that satisfies same error amplitude of the vector, Peak Code Domain Error and adjacent-channel power leakage ratio, can obtain slicing effect preferably, get final product so that the multi-transceiver combination channel signal behind the slicing has lower peak-to-average force ratio, but this scheme mainly is intended for cdma system.If directly scheme shown in Figure 1 is applied to ofdm system, because the modulation coding mode of the subcarrier on the different OFDM symbols, carrier powers etc. all may be inequality, the performance loss that allows also can be different, if all use identical filter coefficient to carry out matched filtering to each OFDM symbol, for example come the designing filter coefficient with high-order modulating, the slicing ability of matched filtering will be very limited, the peak-to-average force ratio of multi-carrier OFDM systems is still very high after the matched filtering, and with bigger error vector magnitude (EVM, Error Vector Magnitude) loss comes the selective filter coefficient, must cause the subcarrier of high-order modulating can not satisfy the EVM demand that agreement is stipulated, have a strong impact on the link performance of system.
Even suitably improvement is done in the matched filtering among Fig. 1, for example make the different filter coefficient of use on each OFDM symbol, also can cause two intersymbol a part of sampled points of OFDM that serious distortion takes place, cause more serious band external leakage and intersymbol interference, thereby obviously worsen the EVM of high order modulation subcarrier in the OFDM carrier wave, and the band external leakage can make also the channel signal after peak-to-average force ratio suppresses can't satisfy the spectrum mask that agreement is stipulated.
As seen through the above analysis, the slicing scheme of utilizing matched filtering to realize shown in Figure 1 can not directly be applied in the multi-carrier OFDM systems, and does not also realize the scheme that effective peak-to-average force ratio suppresses at multi-carrier OFDM systems at present.
Summary of the invention
The method that the embodiment of the invention provides a kind of multi-carrier OFDM systems peak-to-average force ratio to suppress, this method can effectively suppress the peak-to-average force ratio in the multi-carrier OFDM systems.
The device that the embodiment of the invention provides a kind of multi-carrier OFDM systems peak-to-average force ratio to suppress, this device can effectively suppress the peak-to-average force ratio in the multi-carrier OFDM systems.
Technical scheme of the present invention is achieved in that
The method that peak-to-average force ratio suppresses in a kind of multi-carrier orthogonal frequency division multiplexing system, this method comprises:
On each orthogonal frequency division multiplex OFDM symbol,, close the road and become time domain multi-transceiver combination channel signal the base band frequency-region signal of each carrier wave;
For the default thresholding of the peak value of multi-transceiver combination channel signal, from described multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, the length of described clipped noise is symbol lengths;
Obtain the frequency domain response of the clipped noise of described each carrier wave of correspondence, oppositely be superimposed to the base band frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, carry out peak-to-average force ratio and suppress;
Described from the multi-transceiver combination channel signal, the clipped noise that obtains corresponding each carrier wave comprises:
Extract the part that peak value in the described multi-transceiver combination channel signal surpasses described default thresholding, and calculate the part that surpasses described default thresholding and the amplitude ratio of multi-transceiver combination channel signal;
Use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, as the clipped noise of multi-transceiver combination channel signal;
In the clipped noise of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths;
The clipped noise of the symbol lengths of described intercepting is distributed to each carrier wave;
Or,
Extract the part that peak value in the described multi-transceiver combination channel signal surpasses described default thresholding, and calculate the part that surpasses described default thresholding and the amplitude ratio of multi-transceiver combination channel signal;
Use described amplitude ratio to take advantage of channel signal before each carrier wave closes the road again, as the clipped noise of each carrier wave;
In the clipped noise of described each carrier wave, the clipped noise of intercepting symbol lengths.
The device that peak-to-average force ratio suppresses in a kind of multi-carrier orthogonal frequency division multiplexing system, this device comprises:
Multi-transceiver combination channel signal module is used at each orthogonal frequency division multiplex OFDM symbol, with the base band frequency-region signal of each carrier wave, closes the road and becomes the multi-transceiver combination channel signal;
The time delay module is used for the base band frequency-region signal of described each carrier wave is carried out time delay;
The clipped noise acquisition module is used for from described multi-transceiver combination channel signal, obtains the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths;
Peak-to-average force ratio suppresses module, is used to obtain the frequency domain response of the clipped noise of each carrier wave of described correspondence, symbol lengths, and the base band frequency-region signal of delaying when oppositely being superimposed to corresponding carrier wave carries out peak-to-average force ratio and suppresses;
Described clipped noise acquisition module comprises:
The index evaluation unit, be used to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, continue to judge that whether the peak-to-average force ratio of multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, described multi-transceiver combination channel signal is sent to the clipped noise acquiring unit; Be used to perhaps judge that whether the peak-to-average force ratio of multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, continue to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, described multi-transceiver combination channel signal is sent to the clipped noise acquiring unit;
Clipped noise obtains performance element, is used for obtaining from the multi-transceiver combination channel signal of described index evaluation unit output the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths;
Described clipped noise obtains performance element and comprises:
First extracts the execution subelement, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, as the clipped noise of multi-transceiver combination channel signal;
Subelement is carried out in first intercepting, is used at the current peak-to-average force ratio that described multi-transceiver combination channel signal carries out when to suppress number of times be odd number time, and from the clipped noise afterbody of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths; The current peak-to-average force ratio that carries out at described multi-transceiver combination channel signal suppresses number of times when being even number time, from the clipped noise front portion of described multi-transceiver combination channel signal, and the clipped noise of intercepting symbol lengths;
Distribute and carry out subelement, be used for the clipped noise of described symbol lengths is taken advantage of with the conjugate complex of the FM signal of corresponding carrier wave, obtain the clipped noise of corresponding each carrier wave, the length of described clipped noise is symbol lengths;
Or,
Second extracts the execution subelement, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, described amplitude ratio is taken advantage of the channel signal of each carrier wave again, as the clipped noise of each carrier wave; 1
Subelement is carried out in second intercepting, is used for the clipped noise from described each carrier wave, the clipped noise of corresponding each carrier wave of intercepting, and the length of described clipped noise is symbol lengths.
As seen, the method and apparatus that peak-to-average force ratio suppresses in the embodiment of the invention multi-carrier OFDM systems, on each OFDM symbol, the base band frequency-region signal of each carrier wave is closed road one-tenth time domain multi-transceiver combination channel signal, from this multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, the length of this clipped noise is symbol lengths, again with the frequency domain response of the clipped noise of corresponding each carrier wave, oppositely be superimposed to the frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, thereby, realize effective inhibition to peak-to-average force ratio in the multi-carrier OFDM systems by the extra frequency domain noise that on each carrier wave, oppositely superposes.
Description of drawings
Fig. 1 is the theory diagram of the many matched filterings slicing scheme in the multicarrier system in the prior art;
Fig. 2 is the theory diagram of the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems;
Fig. 3 is the method for suppressing peak to average ratio flow chart in the embodiment of the invention multi-carrier OFDM systems;
Fig. 4 is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, the frequency-region signal realization flow figure that each carrier wave sends at the OFDM symbol;
Fig. 5 is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, multi-transceiver combination channel signal realization flow figure;
Fig. 6 is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, the index evaluation flow chart;
Fig. 7 is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, the principle schematic that clipped noise extracts;
Fig. 8 a～b is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, the principle schematic of clipped noise intercepting;
Fig. 9 is in the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, and frequency domain response is carried out the principle schematic that amplitude-phase is adjusted;
Figure 10 is the peak-to-average force ratio restraining device structural representation in the embodiment of the invention multi-carrier OFDM systems;
Figure 11 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, first kind of structural representation of clipped noise acquisition module;
Figure 12 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, second kind of structural representation of clipped noise acquisition module;
Figure 13 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, the structural representation of multi-transceiver combination channel signal module;
Figure 14 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, and peak-to-average force ratio suppresses first kind of structural representation of module;
Figure 15 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, and peak-to-average force ratio suppresses second kind of structural representation of module.
Embodiment
For the purpose and the advantage that make the embodiment of the invention is clearer, the embodiment of the invention is described in further detail below in conjunction with accompanying drawing.
Fig. 2 is the theory diagram of the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems.Shown in Figure 2 is example with two carrier waves, the base band frequency-region signal 1 of carrier wave 1 and carrier wave 2 and base band frequency-region signal 2 at first carry out multi-transceiver combination, form the laggard row index evaluation of multi-transceiver combination channel signal, if index evaluation by directly send to intermediate-frequency channel and carry out subsequent treatment, if index evaluation not by from the multi-transceiver combination channel signal, extract clipped noise, and distribute to carrier wave 1 and carrier wave 2 behind the clipped noise that will the extract intercepting symbol lengths.At carrier wave 1, the frequency domain response of clipped noise that acquisition distributes, the clipped noise frequency domain response that uses amplitude-phase to adjust the factor pair acquisition carries out the width of cloth and adjusts mutually, adjusted frequency domain response oppositely is superimposed to the base band frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, carry out peak-to-average force ratio and suppress, identical at carrier wave 2 with the operation of above-mentioned carrier wave 1.Use the new base band frequency-region signal of above-mentioned carrier wave 1 and carrier wave 2 can continue to carry out the operation of multi-transceiver combination again.
Fig. 3 is the flow chart of the method for suppressing peak to average ratio in the embodiment of the invention multi-carrier OFDM systems, and this flow process comprises:
Step 301: on each OFDM symbol,, close the road and become time domain multi-transceiver combination channel signal with the base band frequency-region signal of each carrier wave.
Step 302: from described multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, symbol lengths.
Step 303: with the frequency domain response of the clipped noise of each carrier wave of described correspondence, symbol lengths, the base band frequency-region signal of delaying when oppositely being superimposed to corresponding carrier wave carries out peak-to-average force ratio and suppresses.
The method that peak-to-average force ratio suppresses in the embodiment of the invention multi-carrier OFDM systems, on each OFDM symbol, the base band frequency-region signal of each carrier wave is closed road one-tenth time domain multi-transceiver combination channel signal, from this multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, symbol lengths, again with the frequency domain response of the clipped noise of corresponding each carrier wave, symbol lengths, the frequency-region signal of delaying when oppositely being superimposed to corresponding carrier wave, thereby, realize effective inhibition to peak-to-average force ratio in the multi-carrier OFDM systems by the extra frequency domain noise that on each carrier wave, oppositely superposes.
Obtain from the formation of multi-transceiver combination channel signal, index evaluation, clipped noise respectively below, and peak-to-average force ratio suppresses several aspects, describe the method that the embodiment of the invention provides in detail.
1) the multi-transceiver combination channel signal forms.
At first, obtain the frequency-region signal that each carrier wave sends at the OFDM symbol, its realization flow as shown in Figure 4, this flow process comprises:
Step 401: on each OFDM symbol of multi-carrier OFDM systems, the data-signal on each carrier wave is encoded according to the predictive encoding mode.
Step 402: the data-signal of each carrier wave after will encoding, carry out constellation mapping according to the predetermined modulation mode.
Step 403:, insert control informations such as pilot signal at the data-signal of each carrier wave after the constellation mapping.
Step 404: to free time (TR, the Tone Reservation) subcarrier of each carrier wave and about the protection subcarrier put 0, generate the base band frequency-region signal of each carrier wave.
Secondly, the base band frequency-region signal of each carrier wave is closed the road become the multi-transceiver combination channel signal, i.e. multi-transceiver combination channel signal, it realizes stream as shown in Figure 5, and closing the road with the base band frequency-region signal of two carrier waves is example, and this flow process comprises:
Step 501: on each OFDM symbol, the base band frequency-region signal of each carrier wave is handled through high power speed IFFT, formed time-domain signal.
Step 502:, form the channel signal of each carrier wave for the time-domain signal after the IFFT processing adds CP.
Step 503: utilize NCO that the channel signal of each carrier wave of obtaining in the step 502 is modulated to separately frequency, specifically can by directly and FM signal take advantage of Digital Implementation again, it is continuous that the phase place of each OFDM intersymbol FM signal keeps.At last the channel signal of each the OFDM carrier wave behind the frequency modulation is added up one by one and obtains multi-transceiver combination channel signal y (n) in the multi-carrier OFDM systems, can represent with following formula:
y ( n ) = Σ l = 1 L x l ( n ) e j 2 π f i ( n + N 0 l ) ΔT , n = 0,1 , . . . , Sym _ L + CP _ L - 1 .
F in the following formula l(l=1,2 .. L) is the frequency modulation frequency of each OFDM carrier wave, and the frequency difference of intercarrier satisfies configuration needs, and L is a carrier number; N 0 lBe the phase place of the FM signal of l carrier wave, guarantee that by it the phase place of each OFDM intersymbol FM signal is continuous at the 0th sampled point of OFDM symbol; Δ T is the sampled point interval of multi-transceiver combination channel signal; CP _ LBe CP district sampled point number in the multi-transceiver combination channel signal, Sym _ LBe sampled point number in sign field in the multi-transceiver combination channel signal; x l(n) close channel signal before the road for each carrier wave.
2) index evaluation.
For the multi-transceiver combination channel signal that forms by frequency-region signal, before carrying out the peak-to-average force ratio inhibition, can at first judge by index evaluation whether this multi-transceiver combination channel signal needs to carry out peak-to-average force ratio and suppress, slicing algorithm stopping criterion specifically can be set, comprise: the equal ratio of maximum iteration time and target peak.Fig. 6 shows the flow process that These parameters is estimated, and this flow process comprises:
Step 601: judge that the peak-to-average force ratio that the multi-transceiver combination channel signal is carried out suppresses iterations, whether greater than maximum iteration time, if direct execution in step 604, otherwise execution in step 602.
Step 602: whether the peak-to-average force ratio of judging the multi-transceiver combination channel signal is less than the equal ratio of target peak, if direct execution in step 604, otherwise execution in step 603.
Step 603: continue to carry out the multi-transceiver combination channel signal is carried out the step that clipped noise extracts.
In this step, the result of index evaluation continues that then the multi-transceiver combination channel signal is carried out clipped noise and extracts if the multi-transceiver combination channel signal still need carry out peak-to-average force ratio to be suppressed, and extracts the back at clipped noise and continues to carry out steps such as follow-up clipped noise intercepting.
Step 604: the multi-transceiver combination channel signal is sent to intermediate-frequency channel.
Above-mentioned steps 601 and step 602 do not have strict ordinal relation, what above-mentioned flow process provided is wherein a kind of ordinal relation, whether the peak-to-average force ratio that also can judge the multi-transceiver combination channel signal earlier is less than the equal ratio of target peak, judge that again the peak-to-average force ratio that the multi-transceiver combination channel signal is carried out suppresses iterations, whether greater than maximum iteration time.
3) clipped noise obtains.
In the method that the embodiment of the invention provides, clipped noise obtains and is divided into two kinds of specific implementations.
First kind, be the default thresholding Gate of the peak value of multi-transceiver combination channel signal, determine that peak value is greater than the part of this extraction thresholding in the multi-transceiver combination channel signal, calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, clipped noise as the multi-transceiver combination channel signal, in the clipped noise of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths is distributed to each carrier wave with the clipped noise of symbol lengths of intercepting again.Fig. 7 shows the realization principle of said extracted multi-transceiver combination channel signal greater than default thresholding part.
Can be in the following way during the said process specific implementation.Each sampled point of multi-transceiver combination channel signal is expressed as y (n)=y I(n)+j * y Q(n), y wherein I(n) be I road input signal, y Q(n) be Q road input signal, signal calculated amplitude A mp (n) and slicing ratio γ (n) are shown below:
Figure GSB00000027865400101
Wherein Amp ( n ) = ( y I ( n ) ) 2 + ( y Q ( n ) ) 2 .
The clipped noise that calculates the multi-transceiver combination channel signal then is as follows:
noise ‾ ( n ) = ( 1 - γ ( n ) ) y ( n ) , t＝0，1，...，Sym _L+CP _L-1。
As seen, the clipped noise length of multi-transceiver combination channel signal is passage length Sym _ L+ CP _ L
Because frequency-domain structure can treated length be the clipped noise of symbol lengths only at every turn, therefore need the clipped noise of above-mentioned multi-transceiver combination channel signal is intercepted processing.A kind of easy and feasible strategy is to suppress at peak-to-average force ratio not at the same level, handle the clipped noise of diverse location in the multi-transceiver combination channel signal, the level here refers to the current iterations that carries out the peak-to-average force ratio inhibition of multi-transceiver combination channel signal, for example the multi-transceiver combination channel signal is current carries out the first time during iteration, is the first order; The multi-transceiver combination channel signal is current to carry out the second time during iteration, is the second level.
When odd number time iteration, from the noise signal of multi-transceiver combination channel signal afterbody intercepting symbol lengths, and when even number time iteration, from the noise signal of the anterior intercepting of multi-transceiver combination channel signal symbol lengths.The realization principle that above-mentioned minute two-stage carried out the clipped noise intercepting as shown in Figure 8, wherein shown in a be odd number time iteration the time processing mode, shown in the b be even number time iteration the time processing mode.The position of clipped noise in passage of different iterative process interceptings is different, thereby after the multi-transceiver combination channel signal is carried out repeatedly iteration, helps suppressing the peak-to-average force ratio of whole channel signal.
After the processing through the clipped noise intercepting, the clipped noise of output symbol length is as follows:
After the clipped noise intercepting, the clipped noise of intercepting is dispensed to each carrier wave, can carry out above-mentioned clipped noise according to the frequency domain response of clipped noise and distribute, can come the clipped noise of multi-transceiver combination channel signal is distributed by taking advantage of when closing the road NCO conjugation again during realization.
If the clipped noise intercepting time is an odd number time iteration, then distribute back l (l=1 ..., L, L are carrier number) clipped noise of individual carrier wave is as follows:
noise l ( n ) = ( 1 - γ ( n + CP _ L ) ) x ( n + CP _ L ) e - j 2 π f l ( l + N 0 + CP _ L ) ΔT , n = 0,1 , . . . , Sym _ L - 1
If be even number time iteration during the clipped noise intercepting, the clipped noise after then distributing is as follows:
noise l ( n ) = ( 1 - γ ( n + CP _ L ) ) x ( n + CP _ L ) e - j 2 π f l ( n + N 0 + CP _ L ) ΔT , n = 0,1 , . . . , Sym _ L - CP _ L - 1 ( 1 - γ ( n - Sym _ L + CP _ L ) ) x ( n - Sym _ L + CP _ L ) e - j 2 π f l ( n + N 0 - Sym _ L + CP _ L ) ΔT , n = Sym _ L - CP _ L , . . . , Sym _ L - 1 .
Second kind, peak value surpasses the part of default thresholding in the extraction multi-transceiver combination channel signal, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, use described amplitude ratio to take advantage of the channel signal of each carrier wave again, clipped noise as each carrier wave, from the clipped noise of described each carrier wave, intercept the clipped noise of symbol lengths again.
Above-mentioned second method can realize as follows.Still calculate slicing ratio γ (n) according to the method in above-mentioned first kind of implementation, the channel signal x that each carrier wave is calculated l(n) direct multiplying each other with the slicing ratio γ (n) that calculates converted, and is shown below:
noise l(n)＝(1-γ(n))x l(n)，
Calculate the clipped noise that has drawn each carrier wave through following formula, directly get final product according to the clipped noise that the rule that intercepts clipped noise in above-mentioned first kind of implementation method intercepts out symbol lengths at each carrier wave.
4) peak-to-average force ratio suppresses.
Clipped noise to each carrier wave, symbol lengths, obtain its frequency domain response in band through high power speed FFT processing, after suitable amplitude, phase place adjustment, oppositely be superimposed to the frequency-region signal of each carrier wave of time-delay back then, thereby the peak-to-average force ratio that is implemented in the multi-carrier OFDM systems suppresses.Perhaps, the frequency domain response of each carrier wave clipped noise of above-mentioned acquisition, can also adopt another kind of mode to realize, promptly at first use the frequency domain response of the outer part of band in each carrier wave clipped noise of filter filtering, low power speed extracts the back and handles the frequency domain response that obtains each carrier wave clipped noise by one times of fast FFT.
Fig. 9 shows above-mentioned each carrier frequency domain response is carried out the realization schematic diagram that amplitude-phase is adjusted.
Amplitude, phase place adjustment that above-mentioned frequency domain response is carried out are adjusted factor control by amplitude, phase place, determine that this amplitude, phase place adjust the factor and need consider subcarrier parameter and TR subcarrier parameter.The subcarrier parameter can be considered from link performance, comprise code rate, constellation modulation system, sub-carrier power, EVM loss, spectrum mask etc., and peak-to-average force ratio performance and implementation complexity are also restricting the configuration of the above-mentioned adjustment factor, therefore should take into full account above-mentioned factor, select suitable amplitude, phase place to adjust the factor.
To the TR subcarrier in each OFDM symbol, these TR subcarriers do not carry any useful signal, allow to dispose amplitude, the phase place adjustment factor arbitrarily in theory, but excessive superimposed noise not only influences the demodulation of receiving terminal data subcarrier on the TR subcarrier, also can reduce the power of transmitter, therefore can comprise that to TR subcarrier parameter amplitude, phase place are adjusted the factor does suitable inhibition, weakens the adverse effect of bringing thus.As can be seen, the embodiment of the invention allows the interior TR subcarrier of OFDM symbol also participate in the peak-to-average force ratio inhibition, made full use of the system physical resource, can obtain better peak-to-average force ratio and suppress effect, and the restriction that the amplitude on the TR subcarrier, phase place are adjusted the factor allowed also the noise superimposed energy is effectively controlled on the TR subcarrier, not only help the demodulation of terminal data subcarrier, and improved the efficient of transmitter indirectly.
Because the characteristics of subcarrier in frequency domain on each OFDM symbol of each carrier wave might be different, therefore amplitude, the phase factor that disposes on different OFDM symbols is also different.
Adjust the principle that the factor is determined in conjunction with amplitude, phase place that the above embodiment of the invention provides, specifically how to carry out determining of amplitude, the phase place adjustment factor, repeat no more here.
Amplitude, phase place are adjusted the frequency domain clipped noise of the factor and each carrier wave and taken advantage of again, take advantage of the result also can be called again eliminated noise.Carrying out peak-to-average force ratio when suppressing, directly with the frequency domain cancellation noise of above-mentioned each carrier wave, oppositely be added to and delay on the base band frequency-region signal of each carrier wave when corresponding, finish a peak-to-average force ratio inhibition.
Figure 10 is the apparatus structure schematic diagram that peak-to-average force ratio suppresses in the embodiment of the invention multi-carrier OFDM systems, and this device comprises:
Multi-transceiver combination channel signal module 11 is used at each OFDM symbol, with the base band frequency-region signal of each carrier wave, closes the road and becomes the multi-transceiver combination channel signal.
Time delay module 12 is used for the base band frequency-region signal of described each carrier wave is carried out time delay.
Clipped noise acquisition module 13 is used for from described multi-transceiver combination channel signal, obtains the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths.
Peak-to-average force ratio suppresses module 14, is used to obtain the frequency domain response of the clipped noise of described each carrier wave of correspondence, and the base band frequency-region signal of delaying when oppositely being superimposed to corresponding carrier wave carries out peak-to-average force ratio and suppresses.
The device that peak-to-average force ratio suppresses in the embodiment of the invention multi-carrier OFDM systems, multi-transceiver combination channel signal module 11, the frequency-region signal of each carrier wave on the OFDM symbol closed the road become time domain multi-transceiver combination channel signal, clipped noise acquisition module 13 is from this multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, peak-to-average force ratio suppresses module 14 again with the frequency domain response of the clipped noise of corresponding each carrier wave, oppositely be superimposed to the frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, thereby, realize effective inhibition to peak-to-average force ratio in the multi-carrier OFDM systems by the extra frequency domain noise that on each carrier wave, oppositely superposes.
In the device that the embodiment of the invention provides, clipped noise acquisition module 13 can comprise two kinds of internal structures, below in conjunction with Figure 11 and Figure 12 explanation.
Above-mentioned clipped noise acquisition module 13 can comprise:
Index evaluation unit 131, be used to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if, the multi-transceiver combination channel signal is sent to intermediate-frequency channel, otherwise continue to judge that whether the peak-to-average force ratio of multi-transceiver combination channel signal is less than the equal ratio of target peak, if, described multi-transceiver combination channel signal is sent to intermediate-frequency channel, otherwise being sent to clipped noise, described multi-transceiver combination channel signal obtains performance element 132; Be used to perhaps judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal is less than the equal ratio of target peak, if, the multi-transceiver combination channel signal is sent to intermediate-frequency channel, otherwise continue to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if, described multi-transceiver combination channel signal is sent to intermediate-frequency channel, obtains performance element 132 otherwise described multi-transceiver combination channel signal is sent to clipped noise.
Clipped noise obtains performance element 132, and the multi-transceiver combination channel signal that is used for 131 outputs from described index evaluation unit obtains the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths.
The structure that above-mentioned clipped noise obtains performance element 132 has two kinds.
First kind, referring to Figure 11, clipped noise obtains performance element 132 and comprises:
First extracts execution subelement 1321, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, as the clipped noise of multi-transceiver combination channel signal.
Subelement 1322 is carried out in first intercepting, is used at the current peak-to-average force ratio that described multi-transceiver combination channel signal carries out when to suppress number of times be odd number time, and from the clipped noise afterbody of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths; The current peak-to-average force ratio that carries out at described multi-transceiver combination channel signal suppresses number of times when being even number time, from the clipped noise front portion of described multi-transceiver combination channel signal, and the clipped noise of intercepting symbol lengths.
Distribute and carry out subelement 1323, be used for the clipped noise of described symbol lengths is taken advantage of with the conjugate complex of the FM signal of corresponding carrier wave, obtain the clipped noise of corresponding each carrier wave, described clipped noise is a symbol lengths.
Second kind, referring to Figure 12, clipped noise acquiring unit 132 can comprise:
Second extracts execution subelement 1324, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculating surpasses the amplitude ratio of the part multi-transceiver combination channel signal of described default thresholding, described amplitude ratio is taken advantage of the channel signal of each carrier wave again, as the clipped noise of each carrier wave.
Subelement 1325 is carried out in second intercepting, is used for the clipped noise from described each carrier wave, the clipped noise of corresponding each carrier wave of intercepting, and described clipped noise is a symbol lengths.
Figure 13 is in the peak-to-average force ratio restraining device in the embodiment of the invention multi-carrier OFDM systems, the structural representation of multi-transceiver combination channel signal module, as shown in figure 13, on the architecture basics of above-mentioned clipped noise acquisition module 13, above-mentioned multi-transceiver combination channel signal module 11 can comprise:
Frequency-region signal unit 111 is used for obtaining the base band frequency-region signal of each carrier wave at each OFDM symbol.
IFFT unit 112 is used for the base band frequency-region signal of described each carrier wave is carried out high power speed IFFT processing.
CP unit 113 is used for described each carrier wave after high power speed IFFT handles is added CP at the frequency-region signal that corresponding OFDM symbol sends.
NCO unit 114 is used for the signal of each carrier wave behind the described CP of adding is modulated to frequency separately.
First unit 115 that adds up, the described channel signal of each carrier wave of frequency separately that is modulated to that is used to add up obtains the multi-transceiver combination channel signal.
On the architecture basics of clipped noise acquisition module 13, the structure that above-mentioned peak-to-average force ratio suppresses module 14 has two kinds.
First kind, referring to Figure 14, peak-to-average force ratio suppresses module 14 and comprises:
High power speed FFT unit 141 is used for the clipped noise of corresponding each carrier wave is carried out high power speed FFT processing, obtains corresponding frequency domain response;
First width of cloth phase adjustment unit 142 is used to use the amplitude of configuration, phase place to adjust the factor, and described frequency domain response is carried out amplitude and phase place adjustment;
Second unit 143 that adds up is used for the base band frequency-region signal of each carrier wave of delaying when described, with described first width of cloth mutually the frequency domain response of the corresponding carrier wave of adjustment unit output oppositely superpose, carry out peak-to-average force ratio and suppress.
Second kind, referring to Figure 15, peak-to-average force ratio suppresses module 14 and comprises:
Filter unit 144 is used for the clipped noise with described each carrier wave of correspondence, the frequency domain response of the outer part of filtering band.
One times of fast FFT unit 145 is used for clipped noise with each carrier wave of described filter cell output and carries out one times of fast FFT and handle, and obtains corresponding frequency domain response.
Second width of cloth phase adjustment unit 146 is used to use the amplitude of configuration, phase place to adjust the factor, and the frequency domain response that described one times of fast FFT unit 145 is exported carries out amplitude and phase place adjustment.
The 3rd unit 147 that adds up is used for the frequency-region signal of each carrier wave base band of delaying when described, with described second width of cloth mutually the corresponding carrier frequency domain response of adjustment unit output oppositely superpose, carry out peak-to-average force ratio and suppress.
The method and apparatus that peak-to-average force ratio suppresses in the embodiment of the invention multi-carrier OFDM systems, on each OFDM symbol, the base band frequency-region signal of each carrier wave is closed road one-tenth time domain multi-transceiver combination channel signal, from this multi-transceiver combination channel signal, obtain corresponding each carrier wave, the clipped noise of symbol lengths, again with each carrier wave of correspondence, the frequency domain response of the clipped noise of symbol lengths, oppositely be superimposed to the frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, thereby, realize effective inhibition to peak-to-average force ratio in the multi-carrier OFDM systems by the extra frequency domain noise that on each carrier wave, oppositely superposes.
In sum, more than be preferred embodiment of the present invention only, be not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (13)

1. the method that peak-to-average force ratio suppresses in the multi-carrier orthogonal frequency division multiplexing system is characterized in that this method comprises:
On each orthogonal frequency division multiplex OFDM symbol,, close the road and become time domain multi-transceiver combination channel signal the base band frequency-region signal of each carrier wave;
For the default thresholding of the peak value of multi-transceiver combination channel signal, from described multi-transceiver combination channel signal, obtain the clipped noise of corresponding each carrier wave, the length of described clipped noise is symbol lengths;
Obtain the frequency domain response of the clipped noise of described each carrier wave of correspondence, oppositely be superimposed to the base band frequency-region signal that corresponding carrier wave is delayed on the OFDM symbol time, carry out peak-to-average force ratio and suppress;
Described from the multi-transceiver combination channel signal, the clipped noise that obtains corresponding each carrier wave comprises:
Extract the part that peak value in the described multi-transceiver combination channel signal surpasses described default thresholding, and calculate the part that surpasses described default thresholding and the amplitude ratio of multi-transceiver combination channel signal;
Use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, as the clipped noise of multi-transceiver combination channel signal;
In the clipped noise of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths;
The clipped noise of the symbol lengths of described intercepting is distributed to each carrier wave;
Or,
Extract the part that peak value in the described multi-transceiver combination channel signal surpasses described default thresholding, and calculate the part that surpasses described default thresholding and the amplitude ratio of multi-transceiver combination channel signal;
Use described amplitude ratio to take advantage of channel signal before each carrier wave closes the road again, as the clipped noise of each carrier wave;
In the clipped noise of described each carrier wave, the clipped noise of intercepting symbol lengths.
2. the method for claim 1 is characterized in that, sets in advance slicing algorithm stopping criterion, comprising: the equal ratio of maximum iteration time and target peak; The described road of closing becomes after the time domain multi-transceiver combination channel signal, obtains before the clipped noise of corresponding each carrier wave, further comprises:
Whether the peak-to-average force ratio of judging described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, continue to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, continue to carry out the step of the clipped noise that from described multi-transceiver combination channel signal, obtains corresponding each carrier wave;
Perhaps, whether the peak-to-average force ratio of judging described multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, continue to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, continue to carry out the step of the clipped noise that from described multi-transceiver combination channel signal, obtains corresponding each carrier wave.
3. method as claimed in claim 2 is characterized in that, the described road of closing becomes time domain multi-transceiver combination channel signal to be:
Obtain the base band frequency-region signal that each carrier wave sends at the OFDM symbol;
Described base band frequency-region signal after high power speed inverse Fourier transform IFFT handles, is added cyclic prefix CP;
The channel signal of each carrier wave behind the described CP of adding is modulated to separately adds up behind the frequency, obtain time domain multi-transceiver combination channel signal.
4. the method for claim 1 is characterized in that, described multi-transceiver combination channel signal is current to carry out iterations that peak-to-average force ratio suppresses for more than once; The clipped noise of described intercepting symbol lengths is: in the iteration that each peak-to-average force ratio suppresses, at the clipped noise of diverse location intercepting symbol lengths.
5. method as claimed in claim 4, it is characterized in that, if the current iterations that carries out the peak-to-average force ratio inhibition of described multi-transceiver combination channel signal is an odd number, described clipped noise at diverse location intercepting symbol lengths is: from the clipped noise afterbody, and the clipped noise of intercepting symbol lengths;
Perhaps, if the current iterations that carries out the peak-to-average force ratio inhibition of described multi-transceiver combination channel signal is an even number, described clipped noise at diverse location intercepting symbol lengths is: from the clipped noise front portion of extracting, and the clipped noise of intercepting symbol lengths.
6. the method for claim 1 is characterized in that, the described clipped noise of symbol lengths with intercepting is distributed to each carrier wave and is:
With the clipped noise of the symbol lengths of described intercepting, the conjugation of the FM signal corresponding with each carrier wave is taken advantage of again, obtains distributing to the clipped noise of each carrier wave.
7. method as claimed in claim 2 is characterized in that, the frequency domain response of described clipped noise with corresponding each carrier wave oppositely is superimposed to before the frequency-region signal that corresponding carrier wave delays on the OFDM symbol time, further comprises:
To the clipped noise of described each carrier wave of correspondence, carry out high power speed Fourier transform FFT and handle, obtain corresponding frequency domain response;
Amplitude, the phase place of using each carrier wave to dispose on subcarrier in frequency domain are adjusted the factor, for corresponding frequency domain response carries out amplitude and phase place adjustment.
8. method as claimed in claim 2 is characterized in that, the frequency domain response of described clipped noise with corresponding each carrier wave oppositely be superimposed to corresponding carrier wave the time frequency-region signal delayed before, further comprise:
Clipped noise to each carrier wave of described correspondence, symbol lengths carries out filtering, the frequency domain response of the outer part of band in the filtering clipped noise, and low power speed extracts the back and handles by FFT, obtains corresponding frequency domain response;
Amplitude, the phase place of using each carrier wave to dispose on subcarrier in frequency domain are adjusted the factor, for corresponding frequency domain response carries out amplitude and phase place adjustment.
9. as claim 7 or 8 described methods, it is characterized in that described amplitude, phase place are adjusted the factor according to subcarrier parameter and idle TR subcarrier parameter configuration;
Described subcarrier parameter comprises: code rate, constellation modulation system, sub-carrier power, error vector magnitude EVM loss, frequency templates, peak-to-average force ratio performance and implementation complexity;
Described TR subcarrier parameter comprises: the amplitude and the phase place that suppress the TR subcarrier.
10. the device that peak-to-average force ratio suppresses in the multi-carrier orthogonal frequency division multiplexing system is characterized in that this device comprises:
Multi-transceiver combination channel signal module is used at each orthogonal frequency division multiplex OFDM symbol, with the base band frequency-region signal of each carrier wave, closes the road and becomes the multi-transceiver combination channel signal;
The time delay module is used for the base band frequency-region signal of described each carrier wave is carried out time delay;
The clipped noise acquisition module is used for from described multi-transceiver combination channel signal, obtains the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths;
Peak-to-average force ratio suppresses module, is used to obtain the frequency domain response of the clipped noise of each carrier wave of described correspondence, symbol lengths, and the base band frequency-region signal of delaying when oppositely being superimposed to corresponding carrier wave carries out peak-to-average force ratio and suppresses;
Described clipped noise acquisition module comprises:
The index evaluation unit, be used to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, continue to judge that whether the peak-to-average force ratio of multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, described multi-transceiver combination channel signal is sent to the clipped noise acquiring unit; Be used to perhaps judge that whether the peak-to-average force ratio of multi-transceiver combination channel signal is less than the equal ratio of target peak, if not, continue to judge that whether the peak-to-average force ratio of described multi-transceiver combination channel signal suppresses iterations greater than maximum iteration time, if not, described multi-transceiver combination channel signal is sent to the clipped noise acquiring unit;
Clipped noise obtains performance element, is used for obtaining from the multi-transceiver combination channel signal of described index evaluation unit output the clipped noise of corresponding each carrier wave, and the length of described clipped noise is symbol lengths;
Described clipped noise obtains performance element and comprises:
First extracts the execution subelement, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, use described amplitude ratio to take advantage of the multi-transceiver combination channel signal again, as the clipped noise of multi-transceiver combination channel signal;
Subelement is carried out in first intercepting, is used at the current peak-to-average force ratio that described multi-transceiver combination channel signal carries out when to suppress number of times be odd number time, and from the clipped noise afterbody of described multi-transceiver combination channel signal, the clipped noise of intercepting symbol lengths; The current peak-to-average force ratio that carries out at described multi-transceiver combination channel signal suppresses number of times when being even number time, from the clipped noise front portion of described multi-transceiver combination channel signal, and the clipped noise of intercepting symbol lengths;
Distribute and carry out subelement, be used for the clipped noise of described symbol lengths is taken advantage of with the conjugate complex of the FM signal of corresponding carrier wave, obtain the clipped noise of corresponding each carrier wave, the length of described clipped noise is symbol lengths;
Or,
Second extracts the execution subelement, be used for extracting the part that described multi-transceiver combination channel signal peak value surpasses default thresholding, and calculate above the part of described default thresholding and the amplitude ratio of multi-transceiver combination channel signal, described amplitude ratio is taken advantage of the channel signal of each carrier wave again, as the clipped noise of each carrier wave;
Subelement is carried out in second intercepting, is used for the clipped noise from described each carrier wave, the clipped noise of corresponding each carrier wave of intercepting, and the length of described clipped noise is symbol lengths.
11. device as claimed in claim 10 is characterized in that, described multi-transceiver combination channel signal module comprises:
The frequency-region signal unit is used for obtaining the base band frequency-region signal of each carrier wave at each OFDM symbol;
Inverse Fourier transform IFFT unit is used for the base band frequency-region signal of described each carrier wave is carried out high power speed IFFT processing;
The cyclic prefix CP unit is used for the signal of described each carrier wave after high power speed IFFT handles is added CP, forms the channel signal of each carrier wave;
Digital controlled oscillator NCO unit is used for the channel signal of described each carrier wave is modulated to frequency separately;
First unit that adds up, the described channel signal of each carrier wave of frequency separately that is modulated to that is used to add up obtains the multi-transceiver combination channel signal.
12. device as claimed in claim 10 is characterized in that, described peak-to-average force ratio suppresses module and comprises:
High power speed Fourier transform FFT unit is used for the clipped noise of corresponding each carrier wave is carried out high power speed FFT processing, obtains corresponding frequency domain response;
First width of cloth phase adjustment unit is used to use the amplitude of configuration, phase place to adjust the factor, and described frequency domain response is carried out amplitude and phase place adjustment;
Second unit that adds up is used for the base band frequency-region signal of each carrier wave of delaying when described, with described first width of cloth mutually the frequency domain response of the corresponding carrier wave of adjustment unit output oppositely superpose, carry out peak-to-average force ratio and suppress.
13. device as claimed in claim 10 is characterized in that, described peak-to-average force ratio suppresses module and comprises:
Filter unit is used for the clipped noise with described each carrier wave of correspondence, the frequency domain response of the outer part of filtering band, and the length of described clipped noise is symbol lengths;
One times of fast FFT unit is used for clipped noise with each carrier wave of described filter cell output and carries out one times of fast FFT and handle, and obtains corresponding frequency domain response;
Second width of cloth phase adjustment unit is used to use the amplitude of configuration, phase place to adjust the factor, and the frequency domain response that described one times of fast FFT unit is exported carries out amplitude and phase place adjustment;
The 3rd unit that adds up is used for the base band frequency-region signal of each carrier wave of delaying when described, with described second width of cloth mutually the corresponding carrier frequency domain response of adjustment unit output oppositely superpose, carry out peak-to-average force ratio and suppress.
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Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101222468B (en) * 2007-12-28 2010-08-04 华为技术有限公司 Peak-to-average ratio restraining method and device in multi-carrier orthogonal frequency division multiplexing system
CN101686146B (en) * 2008-09-28 2013-01-30 华为技术有限公司 Method and equipment for fuzzy query, query result processing and filtering condition processing
CN101510866B (en) * 2008-12-31 2012-07-04 华为技术有限公司 Method, apparatus and transmitter for restraining signal peak-equal power ratio
CN102546498A (en) * 2010-12-20 2012-07-04 上海贝尔股份有限公司 Method and device for obtaining signals with low peak-to-average power ratio based on error vector magnitude
US8798196B2 (en) * 2011-01-25 2014-08-05 Ibiquity Digital Corporation Peak-to-average power ratio reduction for hybrid FM HD radio transmission
CN102857468B (en) * 2012-09-17 2015-05-13 哈尔滨工业大学 SC-FDE (single carrier with frequency-domain equalization) system based on MAP (maximum a posterior) equalization and construction method of pilot frequency structure therein
CN103685121A (en) * 2012-09-26 2014-03-26 电子科技大学 Method and device for inhibiting spectrum leakage in multi-carrier system
EP2904754B1 (en) * 2012-10-05 2019-10-30 Orange Method for the transmission of a multi-carrier signal, and corresponding transmission device and computer program
CN103166898B (en) * 2013-03-29 2015-11-18 东南大学 Based on cycle Zadoff-Chu sequence precise delay tracking in a kind of ofdm system
WO2014176774A1 (en) * 2013-05-02 2014-11-06 Harman International Industries, Incorporated Transformation between time domain and frequency domain based on nearly orthogonal filter banks
CN103718525B (en) * 2013-07-12 2016-10-05 华为技术有限公司 A kind of clipping method, Apparatus and system
CN103338179B (en) * 2013-07-20 2016-02-24 福州大学 The ofdm system peak-to-average force ratio inhibitor that modulation error rate is controlled
CN103441981A (en) * 2013-09-17 2013-12-11 西安电子科技大学 Method for inhibiting peak-to-average power ratio of OFDM (orthogonal frequency division multiplexing) signals of carrier injection based on cut noise
MX359006B (en) 2013-11-26 2018-09-12 Plusn Llc System and method for radio frequency carrier aggregation.
CN104767493B (en) * 2015-02-28 2018-01-23 联想(北京)有限公司 A kind of information processing method and system
KR102397927B1 (en) * 2015-03-31 2022-05-13 삼성전자주식회사 Method and apparatus for peak to average power reduction in wireless communication systems using spectral mask filling
EP3379784A4 (en) * 2015-12-17 2018-11-14 Huawei Technologies Co., Ltd. Clipping method and apparatus
WO2018058410A1 (en) * 2016-09-29 2018-04-05 华为技术有限公司 Clipping method and apparatus
CN106849963B (en) * 2017-03-28 2023-03-31 中国地质大学（武汉） Method and device for reducing peak-to-average power ratio of three-dimensional coherent light orthogonal frequency division multiplexing system
CN108650207B (en) * 2018-05-11 2020-05-15 清华大学 Method and system for reducing peak-to-average ratio of multi-carrier frequency signal in multi-carrier frequency system
CN112653643B (en) * 2019-10-12 2022-07-05 大唐移动通信设备有限公司 Signal processing method and base station
CN112671686B (en) * 2020-12-21 2023-04-14 南方科技大学 Method, device and system for inhibiting peak-to-average power ratio of orthogonal frequency division multiplexing signal
CN113572523B (en) * 2021-07-27 2022-05-13 华中科技大学 Online intrinsic and signal relative transmission delay estimation method for homologous coherent system
CN115174334B (en) * 2022-07-08 2023-07-28 南京邮电大学 Peak average power ratio suppression method and device for radar communication integrated signal
CN115442200A (en) * 2022-11-09 2022-12-06 成都芯通软件有限公司 Crest factor reduction processing method, crest factor reduction processing device, storage medium and communication equipment
WO2024138599A1 (en) * 2022-12-30 2024-07-04 华为技术有限公司 Communication method and related device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1849761A (en) * 2003-09-09 2006-10-18 三星电子株式会社 Apparatus and method for reducing papr in OFDM communication system
CN101035105A (en) * 2007-04-06 2007-09-12 西安电子科技大学 Method and device for reserving the sub-carrier to reduce the peak average power ratio of the OFDM system based on IFFT/FFT
US7292639B1 (en) * 2003-06-05 2007-11-06 Nortel Networks Limited Method and apparatus for peak to average power ratio reduction for orthogonal frequency division multiplex systems
CN101068233A (en) * 2007-07-05 2007-11-07 华为技术有限公司 Method and device for reducing signal peak-to-average power ratio

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101222468B (en) * 2007-12-28 2010-08-04 华为技术有限公司 Peak-to-average ratio restraining method and device in multi-carrier orthogonal frequency division multiplexing system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7292639B1 (en) * 2003-06-05 2007-11-06 Nortel Networks Limited Method and apparatus for peak to average power ratio reduction for orthogonal frequency division multiplex systems
CN1849761A (en) * 2003-09-09 2006-10-18 三星电子株式会社 Apparatus and method for reducing papr in OFDM communication system
CN101035105A (en) * 2007-04-06 2007-09-12 西安电子科技大学 Method and device for reserving the sub-carrier to reduce the peak average power ratio of the OFDM system based on IFFT/FFT
CN101068233A (en) * 2007-07-05 2007-11-07 华为技术有限公司 Method and device for reducing signal peak-to-average power ratio

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