CN106992954A - A kind of clipping method of multi-carrier visible light communication system - Google Patents

A kind of clipping method of multi-carrier visible light communication system Download PDF

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Publication number
CN106992954A
CN106992954A CN201710406630.2A CN201710406630A CN106992954A CN 106992954 A CN106992954 A CN 106992954A CN 201710406630 A CN201710406630 A CN 201710406630A CN 106992954 A CN106992954 A CN 106992954A
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CN
China
Prior art keywords
slicing
signal
peak
ofdm
clipping
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CN201710406630.2A
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Chinese (zh)
Inventor
王家恒
许洋
凌昕彤
梁霄
赵春明
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东南大学
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Priority to CN201710406630.2A priority Critical patent/CN106992954A/en
Publication of CN106992954A publication Critical patent/CN106992954A/en

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B10/00Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/11Arrangements specific to free-space transmission, i.e. transmission through air or vacuum
    • H04B10/114Indoor or close-range type systems
    • H04B10/116Visible light communication
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2614Peak power aspects
    • H04L27/2623Reduction thereof by clipping

Abstract

The invention discloses a kind of clipping method of multi-carrier visible light communication system, by using one kind in ACO OFDM, optimal clipping scheme make it that sending peak-to-average force ratio of the signal at system power amplifier reaches minimum in these three visible ray multicarrier modulation systems of PAM DMT and Flip OFDM, so as to reduce the cost of system, the performance of lifting system.

Description

A kind of clipping method of multi-carrier visible light communication system
Technical field
The present invention relates to wireless light communication technical field, especially a kind of slicing side of multi-carrier visible light communication system Method.
Background technology
Many advantages, such as LED has service life length, energy-conservation, high luminous efficiency, is widely used in room lighting, not Progressively to replace traditional fluorescent lamp and incandescent lamp etc., the indoor lighting device as main flow.Recently research have indicated that, LED devices Part can also carry out the digital communication of high speed while illumination, and LED-based indoor visible light communication system has cost Low, transmission rate is high, good confidentiality the advantages of, therefore, it is considered to be a kind of important indoor wireless communication technology.It is indoor visible Optic communication is compared with existing radio communication, with environmental protection, without the advantage such as electromagnetic radiation, frequency spectrum resource be abundant, this Outside, indoor visible light communication is particularly suitable for applications in the occasion that some wireless devices are prohibitted the use of, such as aircraft, hospital.
Different from traditional twireless radio-frequency communication system, intensity modulated is generally used in visible light communication system straight Detection technique is connect, because in visible light communication system, generally uses luminous intensity to carry information, and LED Luminous intensity can only be nonnegative real number, therefore complex signal can not be used as in conventional radio frequency field.Therefore in visible ray The signal to be transmitted in communication system will all undergo the process that optical signal is converted into by electric signal, i.e., signal is converted at information source Non-negative electric signal drives LED.Orthogonal frequency division multiplexi (OFDM) is widely used in indoor visible light communication system. Orthogonal frequency division multiplexi is furtherd investigate and widely used already in conventional radio frequency communication system, and the technology has some only Special advantage, for example:The availability of frequency spectrum is high, mitigating frequency-selective fading, anti-ISI, and modulation /demodulation is simple and is easy to real It is existing, the advantages of receiving terminal is without complicated balancing technique.In the indoor visible light communication system based on OFDM, due to drive LED, power amplifier is essential.The influence most important index of power amplifier service behaviour is the peak-to-average force ratio of signal, higher signal peak The requirement for comparing power amplifier is just higher, it is desirable to which power amplifier has larger linear dynamic working range, and this can greatly increase power amplifier Cost, and cause power amplifier performance it is unstable.In the indoor visible light communication system based on OFDM, intensity is used Direct Inspection Technology is modulated, the signal needed for for driving LED is positive signal, inevitably introduce slicing to ensure letter Number single polarization.
The content of the invention
The technical problems to be solved by the invention are there is provided a kind of clipping method of multi-carrier visible light communication system, It can be optimized under ACO-OFDM, PAM-DMT and Flip-OFDM these three OFDM modulation systems using optimal clipping scheme Signal peak-to-average ratio at power amplifier, so that reduce power amplifier cost, lifting system performance.
In order to solve the above technical problems, the present invention provides a kind of clipping method of multi-carrier visible light communication system, including Following steps:
(1) bit stream of high speed serialization is converted into the low rate data streams of multidiameter delay by serioparallel exchange buffer;
(2) low rate data streams are mapped to frequency domain constellation point by amplitude modulation(PAM);
(3) frequency domain constellation point carries out conjugation symmetrical treatment;
(4) Fast Fourier Transform (FFT) is carried out to meeting the symmetrical frequency-region signal of conjugation, obtains real value time domain signal to be sent;
(5) obtained time domain real-valued signal is subjected to parallel-serial conversion, is converted into the serial time domain data signal of high speed;
(6) to discrete time-domain digital signal by digital-to-analogue conversion into continuous time analog signal;
(7) analog signal to time domain passes through power amplifier progress power amplification processing;
(8) zero passage slicing is carried out to the signal after power amplifier;
(9) the signal driving LED after zero passage slicing sends the visible light signal for including information.
It is preferred that, in step (2), the data flow of low-speed parallel passes through orthogonal in ACO-OFDM and Flip-OFDM systems Amplitude modulation(PAM), the data flow of low-speed parallel is mapped to frequency domain constellation point by pulse amplitude modulation in PAM-DMT systems.
It is preferred that, in step (3), the data in ACO-OFDM in even subcarriers are set to 0;It is full in Flip-OFDM The general conjugation of foot is symmetricalThe frequency domain star for obtaining pulse amplitude modulation PAM in PAM-DMT Seat point is multiplied by unit imaginary number as imaginary part and then carries out conjugation symmetrical treatment;S will be kept in conjugation symmetrical treatment0=SN/2 =0, N are the digital-to-analogue of subcarrier, SkFor the transmission symbol on k-th of subcarrier.
It is preferred that, in step (8), zero passage slicing is carried out to the signal after power amplifier, it is right in ACO-OFDM and PAM-DMT Negative loop is directly abandoned, and is attached to after being inverted in Flip-OFDM to negative loop behind positive portions and is constituted a complete frame.
It is preferred that, in step (8), for there is the ACO-OFDM systems of N number of subcarrier, the time-domain signal of its IFFT outputs exists The CCDF expression formula of peak-to-average force ratio before non-slicing isDue to it Time-domain signal has symmetry, i.e. sn+N/2=-snN=0 ... N/2-1, therefore typically zero passage slicing is taken it without losing Lose any information and can guarantee that the nonnegativity of signal, the peak-to-average force ratio CCDF of signal is after zero passage slicingTherefore identical CCDF value, the peak-to-average ratio before slicing is only Half after slicing, therefore slicing can bring 3dB peak-to-average force ratio penalty, therefore optimal slicing in ACO-OFDM systems Scheme is to carry out slicing in analog domain, i.e., first cross power amplifier, then carry out slicing.
It is preferred that, in step (8), for there is the PAM-DMT systems of N number of subcarrier, the time-domain signal of its IFFT outputs exists Peak-to-average force ratio CCDF expression formula before non-slicing isDue to its time domain Signal has odd symmetry characteristic, i.e. sN-n=-snN=1 ..., N/2-1, therefore typically zero passage slicing is taken it without losing Lose any information and can guarantee that the nonnegativity of signal, the peak-to-average force ratio CCDF of signal is after zero passage slicingTherefore it is the same with ACO-OFDM, for identical CCDF value, Peak-to-average ratio before slicing is only the half after slicing, therefore slicing can bring 3dB peak-to-average force ratio penalty, therefore Optimal clipping scheme is to carry out slicing in analog domain in PAM-DMT, i.e., first cross power amplifier slicing again.
It is preferred that, in step (8), for having the Flip-OFDM systems of N number of subcarrier, the time-domain signal of its IFFT outputs Peak-to-average force ratio CCDF before non-slicing isBecause it is to be divided into signal Non- negative part and negative loop, therefore do not lose any information after being inverted to negative loop and ensure that the nonnegativity of signal, Zero passage slicing and invert after signal peak-to-average ratio CCDF expression formula be Therefore under the conditions of identical peak-to-average force ratio CCDF value, the peak-to-average ratio after slicing is twice before slicing, because This slicing brings 3dB peak-to-average force ratio penalty, therefore optimal clipping scheme in Flip-OFDM is cut in analog domain Ripple, i.e., first cross power amplifier slicing again.
Beneficial effects of the present invention are:Given by the present invention analog domain carry out slicing clipping scheme be it is optimal, It can guarantee that the peak-to-average force ratio at system power amplifier is minimum by using this scheme, so as to save the constructions cost of system, and cause system Stability is improved;Optimal clipping scheme given by the present invention is that analog domain carries out simulation slicing, i.e., first cross slicing after power amplifier, For general time-domain digital slicing, constructions cost can be saved using the system of scheme proposed by the invention, because compared with High peak-to-average force ratio has higher requirement to power amplifier, system cost can be caused too high;The stability for the system that the present invention is also lifted, because The performance for the power amplifier that larger peak-to-average force ratio is is simultaneously unstable.
Brief description of the drawings
Fig. 1 is ACO-OFDM indoor visible light communication systems transmitting terminal structural representation of the present invention.
Fig. 2 simulates clipping scheme with using numeral clipping scheme peak-to-average force ratio profiles versus to be used in ACO-OFDM of the present invention Schematic diagram.
Fig. 3 is PAM-DMT indoor visible light communication systems transmitting terminal structural representation of the present invention.
Fig. 4 simulates clipping scheme with using numeral clipping scheme peak-to-average force ratio profiles versus to be used in PAM-DMT of the present invention Schematic diagram.
Fig. 5 is Flip-OFDM indoor visible light communication systems transmitting terminal structural representation of the present invention.
Fig. 6 is with being distributed pair using digital clipping scheme peak-to-average force ratio in Flip-OFDM of the present invention using simulation clipping scheme Compare schematic diagram.
Embodiment
As shown in Fig. 1,3 and 5, a kind of clipping method of multi-carrier visible light communication system comprises the following steps:
(1) bit stream of high speed serialization is converted into the low rate data streams of multidiameter delay by serioparallel exchange buffer;
(2) data flow of low-speed parallel is by quadrature amplitude modulation in ACO-OFDM and Flip-OFDM systems, in PAM- The data flow of low-speed parallel is mapped to frequency domain constellation point by pulse amplitude modulation in DMT systems;
(3) it is conjugated symmetrical treatment:Data in ACO-OFDM in even subcarriers are set to 0;Met in Flip-OFDM General conjugation is symmetricalThe frequency domain star for obtaining pulse amplitude modulation (PAM) in PAM-DMT Seat point is multiplied by unit imaginary number as imaginary part and then carries out conjugation symmetrical treatment.Note that in conjugation symmetrical treatment S will be kept0= SN/2=0;
(4) Fast Fourier Transform Inverse is carried out to meeting the symmetrical frequency-region signal of conjugation, obtains that real value time domain is pending to deliver letters Number;
(5) obtained time domain real-valued signal is subjected to parallel-serial conversion, is converted into the serial time domain signal of high speed;
(6) to discrete time-domain digital signal by digital-to-analogue conversion into continuous time analog signal;
(7) analog signal to time domain passes through power amplifier progress power amplification processing;
(8) zero passage slicing is carried out to the signal after power amplifier, negative loop directly lost in ACO-OFDM and PAM-DMT Abandon, be attached to after being inverted in Flip-OFDM to negative loop behind positive portions and constitute a complete frame;
(9) driving LED sends the visible light signal for including information.
As illustrated in fig. 1 and 2, for there is the ACO-OFDM systems of N number of subcarrier, the time-domain signal of its IFFT outputs is not being cut The CCDF expression formula of the peak-to-average force ratio of wavefront isDue to its time domain letter Number have symmetry, i.e. sn+N/2=-snN=0 ... N/2-1, therefore typically take it zero passage slicing any without losing The peak-to-average force ratio CCDF of signal is after information and the nonnegativity that can guarantee that signal, zero passage slicingTherefore identical CCDF value, the peak-to-average ratio before slicing is only Half after slicing, therefore slicing can bring 3dB peak-to-average force ratio penalty, therefore optimal slicing in ACO-OFDM systems Scheme is to carry out slicing in analog domain, i.e., first cross power amplifier, then carry out slicing.Fig. 2 illustrates the ACO- in N=1024 subcarriers Peak-to-average force ratio performance curve of the signal after simulation slicing and after digital slicing compares in ofdm system, it can be seen that simulation is cut Ripple has 3dB performance boost than digital slicing.
As shown in Figures 3 and 4, for there is the PAM-DMT systems of N number of subcarrier, the time-domain signal of its IFFT outputs is not being cut The peak-to-average force ratio CCDF expression formula of wavefront isDue to its time-domain signal With odd symmetry characteristic, i.e. sN-n=-snN=1 ..., N/2-1, therefore typically take it zero passage slicing to appoint without losing The peak-to-average force ratio CCDF of signal is after what information and the nonnegativity that can guarantee that signal, zero passage slicingTherefore it is the same with ACO-OFDM, for identical CCDF value, Peak-to-average ratio before slicing is only the half after slicing, therefore slicing can bring 3dB peak-to-average force ratio penalty, therefore Optimal clipping scheme is to carry out slicing in analog domain in PAM-DMT, i.e., first cross power amplifier slicing again.Fig. 4 is illustrated in N=1024 Peak-to-average force ratio performance curve of the signal after simulation slicing and after digital slicing compares in PAM-DMT systems during subcarrier, Cong Zhongke To find out that simulation slicing has 3dB performance boost than digital slicing.
As it can be seen in figures 5 and 6, for there is the Flip-OFDM systems of N number of subcarrier, the time-domain signal of its IFFT outputs is not Peak-to-average force ratio CCDF before slicing isDue to its be signal is divided into it is non- Negative part and negative loop, therefore do not lose any information after being inverted to negative loop and ensure that the nonnegativity of signal, mistake Zero slicing and invert after signal peak-to-average ratio CCDF expression formula be Therefore under the conditions of identical peak-to-average force ratio CCDF value, the peak-to-average ratio after slicing is twice before slicing, because This slicing brings 3dB peak-to-average force ratio penalty, therefore optimal clipping scheme in Flip-OFDM is cut in analog domain Ripple, i.e., first cross power amplifier slicing again.Fig. 6 illustrates in N=1024 subcarriers in Flip-OFDM systems signal after simulation slicing Compare with the peak-to-average force ratio performance curve after digital slicing, it can be seen that simulation slicing has 3dB performance than digital slicing Lifting.
Although the present invention is illustrated and described with regard to preferred embodiment, it is understood by those skilled in the art that Without departing from scope defined by the claims of the present invention, variations and modifications can be carried out to the present invention.

Claims (7)

1. a kind of clipping method of multi-carrier visible light communication system, it is characterised in that comprise the following steps:
(1) bit stream of high speed serialization is converted into the low rate data streams of multidiameter delay by serioparallel exchange buffer;
(2) low rate data streams are mapped to frequency domain constellation point by amplitude modulation(PAM);
(3) frequency domain constellation point carries out conjugation symmetrical treatment;
(4) Fast Fourier Transform (FFT) is carried out to meeting the symmetrical frequency-region signal of conjugation, obtains real value time domain signal to be sent;
(5) obtained time domain real-valued signal is subjected to parallel-serial conversion, is converted into the serial time domain data signal of high speed;
(6) to discrete time-domain digital signal by digital-to-analogue conversion into continuous time analog signal;
(7) analog signal to time domain passes through power amplifier progress power amplification processing;
(8) zero passage slicing is carried out to the signal after power amplifier;
(9) the signal driving LED after zero passage slicing sends the visible light signal for including information.
2. the clipping method of multi-carrier visible light communication system as claimed in claim 1, it is characterised in that in step (2), The data flow of low-speed parallel is by quadrature amplitude modulation in ACO-OFDM and Flip-OFDM systems, the low speed in PAM-DMT systems Parallel data flow is mapped to frequency domain constellation point by pulse amplitude modulation.
3. the clipping method of multi-carrier visible light communication system as claimed in claim 1, it is characterised in that in step (3), Data in ACO-OFDM in even subcarriers are set to 0;General conjugation is met in Flip-OFDM symmetricalThe frequency domain constellation point for obtaining pulse amplitude modulation PAM in PAM-DMT is with unit imaginary number It is used as imaginary part and then progress conjugation symmetrical treatment;S will be kept in conjugation symmetrical treatment0=SN/2=0, N are the number of subcarrier Mould, SkFor the transmission symbol on k-th of subcarrier.
4. the clipping method of multi-carrier visible light communication system as claimed in claim 1, it is characterised in that right in step (8) Signal after power amplifier carries out zero passage slicing, negative loop is directly abandoned in ACO-OFDM and PAM-DMT, in Flip- It is attached to after being inverted in OFDM to negative loop behind positive portions and constitutes a complete frame.
5. the clipping method of multi-carrier visible light communication system as claimed in claim 4, it is characterised in that right in step (8) In the ACO-OFDM systems for having N number of subcarrier, the complimentary cumulative of peak-to-average force ratio of the time-domain signal that its IFFT is exported before non-slicing Distribution function expression formula isBecause its time-domain signal has symmetry, i.e. sn+N/2=- snN=0 ... N/2-1, therefore general zero passage slicing is taken it without the non-negative losing any information and can guarantee that signal The peak-to-average force ratio CCDF of signal is after property, zero passage slicingTherefore phase Peak-to-average ratio before same CCDF value, slicing is only the half after slicing, therefore slicing can bring 3dB peak Than penalty, therefore optimal clipping scheme in ACO-OFDM systems is to carry out slicing in analog domain, i.e., first cross power amplifier, Slicing is carried out again.
6. the clipping method of multi-carrier visible light communication system as claimed in claim 4, it is characterised in that right in step (8) In the PAM-DMT systems for having N number of subcarrier, peak-to-average force ratio complimentary cumulative distribution of the time-domain signal that its IFFT is exported before non-slicing Function expression isBecause its time-domain signal has odd symmetry characteristic, i.e. sN-n=-sn N=1 ..., N/2-1, thus it is general take it zero passage slicing without the nonnegativity losing any information and can guarantee that signal, The peak-to-average force ratio CCDF of signal is after zero passage slicingTherefore it is same ACO-OFDM is the same, for identical CCDF value, and the peak-to-average ratio before slicing is only the half after slicing, Therefore slicing can bring 3dB peak-to-average force ratio penalty, therefore optimal clipping scheme in PAM-DMT is carried out in analog domain Slicing, i.e., first cross power amplifier slicing again.
7. the clipping method of multi-carrier visible light communication system as claimed in claim 4, it is characterised in that right in step (8) In the Flip-OFDM systems for having N number of subcarrier, peak-to-average force ratio complimentary cumulative point of the time-domain signal that its IFFT is exported before non-slicing Cloth function isBecause it is that signal is divided into non-negative part and negative loop, thus it is right Any information is not lost after negative loop reversion and ensure that the nonnegativity of signal, the signal peak-to-average power after zero passage slicing and reversion It is than CCDF expression formulaTherefore it is complementary in identical peak-to-average force ratio Under the conditions of cumulative distribution function value, the peak-to-average ratio after slicing is twice before slicing, therefore slicing brings 3dB peak-to-average force ratio It can deteriorate, therefore optimal clipping scheme in Flip-OFDM is to carry out slicing in analog domain, i.e., first cross power amplifier slicing again.
CN201710406630.2A 2017-06-02 2017-06-02 A kind of clipping method of multi-carrier visible light communication system CN106992954A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111130650A (en) * 2019-12-30 2020-05-08 武汉邮电科学研究院有限公司 Method and device for generating intensity-modulated directly received optical signal and method and device for receiving intensity-modulated directly received optical signal

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104184693A (en) * 2014-09-09 2014-12-03 东南大学 DCO-OFDM system direct current bias setting method applicable to visible light communication
CN104753849A (en) * 2015-04-21 2015-07-01 东南大学 MIMO DCO-OFDM communication method, signal receiving device and system
CN104836758A (en) * 2015-05-07 2015-08-12 东南大学 MIMO ACO-OFDM iteration receiving method in wireless optical communication system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104184693A (en) * 2014-09-09 2014-12-03 东南大学 DCO-OFDM system direct current bias setting method applicable to visible light communication
CN104753849A (en) * 2015-04-21 2015-07-01 东南大学 MIMO DCO-OFDM communication method, signal receiving device and system
CN104836758A (en) * 2015-05-07 2015-08-12 东南大学 MIMO ACO-OFDM iteration receiving method in wireless optical communication system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王家恒等: "PAPR Analysis for OFDMVisible Light Communication", 《OPTICS EXPRESS》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111130650A (en) * 2019-12-30 2020-05-08 武汉邮电科学研究院有限公司 Method and device for generating intensity-modulated directly received optical signal and method and device for receiving intensity-modulated directly received optical signal
CN111130650B (en) * 2019-12-30 2020-12-29 武汉邮电科学研究院有限公司 Method and device for generating intensity-modulated directly received optical signal and method and device for receiving intensity-modulated directly received optical signal

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