CN110289886A - The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum - Google Patents

The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum Download PDF

Info

Publication number
CN110289886A
CN110289886A CN201910511634.6A CN201910511634A CN110289886A CN 110289886 A CN110289886 A CN 110289886A CN 201910511634 A CN201910511634 A CN 201910511634A CN 110289886 A CN110289886 A CN 110289886A
Authority
CN
China
Prior art keywords
dft
signal
16qam
ofdm
subcarriers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201910511634.6A
Other languages
Chinese (zh)
Inventor
董泽
由家林
陈逸凡
吴新星
张凯明
肖庆华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huaqiao University
Original Assignee
Huaqiao University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huaqiao University filed Critical Huaqiao University
Priority to CN201910511634.6A priority Critical patent/CN110289886A/en
Publication of CN110289886A publication Critical patent/CN110289886A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/516—Details of coding or modulation
    • 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
    • H04L27/2602—Signal structure
    • 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
    • H04L27/2626—Arrangements specific to the transmitter only
    • H04L27/2627—Modulators
    • 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
    • H04L27/2697—Multicarrier modulation systems in combination with other modulation techniques
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/3405—Modifications of the signal space to increase the efficiency of transmission, e.g. reduction of the bit error rate, bandwidth, or average power
    • H04L27/3411—Modifications of the signal space to increase the efficiency of transmission, e.g. reduction of the bit error rate, bandwidth, or average power reducing the peak to average power ratio or the mean power of the constellation; Arrangements for increasing the shape gain of a signal set
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/3488—Multiresolution systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0062—Network aspects
    • H04Q11/0067—Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optical Communication System (AREA)

Abstract

A kind of OFDM-WDM-PON method and system that PAPR is reduced using DFT spread spectrum of the present invention, comprising: generate pseudo-random binary bit stream as downlink data；After serial/parallel conversion, carry out 16QAM digital modulation mapping, leaf transformation and N-M point subcarrier Mapping implementation DFT-S in M point discrete Fourier are carried out to modulated signal, using the inverse transformation of N point quick Fourier and addition cyclic prefix, parallel/serial conversion and D/A switch, DFT-S ofdm signal is obtained；In optical line terminal, DFT-S ofdm signal is loaded on light carrier by MZ Mach-Zehnder；The optical signal of different wave length is synthesized into optical signal all the way by coupler, is transmitted to optical network unit through ODN, electric signal is converted optical signals into using photodetector, then restore original signal via transmitting terminal inverse process；Upstream data is transferred to OLT from ONU by the inverse process of downlink data.

Description

The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum
Technical field
The present invention relates to fiber optic communication field more particularly to a kind of OFDM-WDM- that PAPR is reduced using DFT spread spectrum PON method and system.
Background technique
With the development of offering multiple services of network, various businesses are continuously increased wideband requirements, OFDM-WDM-PON system Because having the unique advantage for solving access network technology rate limit, and become the preferable selection of Next Generation Access technology.Phase Than traditional WDM-PON system, by orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) technology introduce light passive access network (Passive optical network, PON) after, transmission speed Rate, resisting chromatic dispersion ability and network management etc. are with the obvious advantage.But since OFDM is multi-transceiver technology, the superposition of each carrier wave Transmission will lead to higher papr (Peak-to-Average Power Ratio, PAPR), this requires Network device Part has the biggish range of linearity, and then increases system cost.Higher papr (PAPR) can also aggravate simultaneously Optical fiber transmits non-linear, so that system performance declines.
Summary of the invention
Reduce PAPR's using DFT spread spectrum it is an object of the invention to overcome the deficiencies of the prior art and provide a kind of Orthogonal frequency division multiplexing (OFDM) and wavelength-division multiplex (WDM) technology are quoted the passive access of light by OFDM-WDM-PON method and system Net (PON) can be improved the utilization rate and performance of optical receiver sensitivity, frequency band, reduce cost.
To achieve the goals above, the technical scheme is that
On the one hand, a kind of OFDM-WDM-PON method that PAPR is reduced using DFT spread spectrum of the present invention, comprising:
Step 101, pseudo-random binary bit stream is generated as original binary bit stream, i.e. downlink data, go here and there/ And convert, make all the way bit stream be divided into M way bit stream, and it is mutually orthogonal by quadrature amplitude modulation 16QAM to be mapped to the road N On subcarrier；Wherein, N > M；
Step 102, leaf transformation DFT in M point discrete Fourier is carried out to the M subcarriers for carrying 16QAM signal, to not carrying letter Number N-M subcarriers carry out zero padding to carry out inverse fast Fourier transform IFFT, addition to N subcarriers after completing spread spectrum Cyclic prefix CP carries out parallel/serial conversion and D/A switch, obtains this group of downlink DFT-S 16QAM-OFDM signal；
Step 103, in optical line terminal OLT, this group of downlink DFT-S 16QAM-OFDM signal is passed through into Mach Zeng De Your modulator MZM is loaded on the light carrier of the different wave length of the generation of the first laser device in OLT, to obtain corresponding wavelength DFT-S 16QAM-OOFDM signal；By ODN acceptance of the bid quasi-monomode fiber SSMF transmission and shunting coupler, by corresponding wavelength DFT-S 16QAM-OOFDM signal is transferred to corresponding optical network unit ONU respectively；The DFT-S 16QAM- of corresponding wavelength OOFDM signal becomes electric DFT-S 16QAM-OFDM signal after photodiode PD, signal by analog/digital conversion and string/ And after converting, cyclic prefix CP is gone, successively carries out leaf inverse transformation IDFT in N point quick Fourier transformation FFT and M point discrete Fourier, QAM demapping finally recovers the binary bit stream of the downlink data of original transmitted by parallel/serial conversion.
Preferably, the method also includes:
Step 201, pseudo-random binary bit stream is generated as original binary bit stream, i.e. upstream data, go here and there/ And convert, make all the way bit stream be divided into M way bit stream, and it is mutually orthogonal by quadrature amplitude modulation 16QAM to be mapped to the road N On subcarrier；Wherein, N > M；
Step 202, leaf transformation DFT in M point discrete Fourier is carried out to the M subcarriers for carrying 16QAM signal, to not carrying letter Number N-M subcarriers carry out zero padding to carry out inverse fast Fourier transform IFFT, addition to N subcarriers after completing spread spectrum Cyclic prefix CP carries out parallel/serial conversion and D/A switch, obtains this group of uplink DFT-S 16QAM-OFDM signal；
Step 203, in different optical network unit ONUs, once by Mach by uplink DFT-S 16QAM-OFDM signal Dare modulator MZM is loaded on the light carrier of the different wave length of second laser transmitting；Pass through photo-coupler and standard single mode By the DFT-S optical signal transmission of uplink to optical line terminal OLT, the light for handling different wave length respectively in the olt carries optical fiber SSMF Corresponding DFT-S OOFDM signal is become electric DFT-S ofdm signal by photodiode PD, passed through by the signal loaded on wave It crosses analog/digital conversion, after serial/parallel conversion, removes cyclic prefix CP, it is discrete successively to carry out N point quick Fourier transformation FFT and M point After inverse Fourier transform IDFT, QAM demapping, the binary system of the upstream data of original transmitted is recovered using parallel/serial conversion Bit stream.
Preferably, in step 102, the M subcarriers for carrying 16QAM signal are carried out in M point discrete Fourier after leaf transformation DFT The frequency domain sample data A of generationkIt is expressed as follows:
Wherein, xmIndicate M original input data, m=0,1 ..., M-1, k=0,1 ..., M-1；J indicates imaginary number list Position；
To the N subcarriers frequency domain sample data c after (N-M) subcarriers zero paddingk′It is expressed as follows:
Wherein, k '=0,1 ..., N-1；
Time domain data { the y that inverse fast Fourier transform (IFFT) is generated is carried out to N subcarriersnIt is expressed as follows:
yn=IFFT { ck′}
Wherein, n=0,1 ..., N-1.
On the other hand, a kind of OFDM-WDM-PON system that PAPR is reduced using DFT spread spectrum of the present invention, comprising:
Downlink data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit Stream, i.e. downlink data carry out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and pass through quadrature amplitude modulation 16QAM is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Downlink DFT-S 16QAM-OFDM signal acquisition module, for carrying out M to the M subcarriers for carrying 16QAM signal Leaf transformation DFT in point discrete Fourier, after completing spread spectrum to the N-M subcarriers progress zero padding for not carrying signal, to N subcarriers Inverse fast Fourier transform IFFT is carried out, cyclic prefix CP is added, carries out parallel/serial conversion and D/A switch, obtain this group of downlink DFT-S 16QAM-OFDM signal；
Downlink signal modulation and recovery module, are used in optical line terminal OLT, by this group of downlink DFT-S 16QAM- Ofdm signal is loaded into the light carrier of the different wave length of the generation of the first laser device in OLT by MZ Mach-Zehnder MZM On, to obtain the DFT-S 16QAM-OOFDM signal of corresponding wavelength；By ODN acceptance of the bid quasi-monomode fiber SSMF transmission and divide The DFT-S 16QAM-OOFDM signal of corresponding wavelength is transferred to corresponding optical network unit ONU by road coupler respectively；It is corresponding The DFT-S 16QAM-OOFDM signal of wavelength becomes electric DFT-S 16QAM-OFDM signal, signal after photodiode PD After analog/digital conversion and serial/parallel conversion, cyclic prefix CP is gone, it is discrete successively to carry out N point quick Fourier transformation FFT and M point Inverse Fourier transform IDFT, QAM demapping finally recovers the binary system of the downlink data of original transmitted by parallel/serial conversion Bit stream.
Preferably, the system also includes:
Upstream data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit Stream, i.e. upstream data carry out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and pass through quadrature amplitude modulation 16QAM is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Uplink DFT-S 16QAM-OFDM signal acquisition module, for carrying out M to the M subcarriers for carrying 16QAM signal Leaf transformation DFT in point discrete Fourier, after completing spread spectrum to the N-M subcarriers progress zero padding for not carrying signal, to N subcarriers Inverse fast Fourier transform IFFT is carried out, cyclic prefix CP is added, carries out parallel/serial conversion and D/A switch, obtain this group of uplink DFT-S 16QAM-OFDM signal；
Uplink signal modulation and recovery module, in different optical network unit ONUs, by uplink DFT-S16QAM- Ofdm signal is loaded on the light carrier of the different wave length of second laser transmitting by MZ Mach-Zehnder MZM；Pass through Photo-coupler and standard single-mode fiber SSMF to optical line terminal OLT, distinguish the DFT-S optical signal transmission of uplink in the olt The signal loaded on the light carrier of different wave length is handled, corresponding DFT-S OOFDM signal is become by photodiode PD Electric DFT-S ofdm signal after serial/parallel conversion, removes cyclic prefix CP, successively carries out in quick Fu of N point by analog/digital conversion In leaf transformation FFT and M point discrete Fourier after leaf inverse transformation IDFT, QAM demapping, original transmitted is recovered using parallel/serial conversion Upstream data binary bit stream.
Preferably, downlink signal modulation and recovery module in, to carry 16QAM signal M subcarriers carry out M point it is discrete The frequency domain sample data A generated after Fourier transformation DFTkIt is expressed as follows:
Wherein, xmIndicate M original input data, m=0,1 ..., M-1, k=0,1 ..., M-1；J indicates imaginary number list Position；
To the N subcarriers frequency domain sample data c after (N-M) subcarriers zero paddingk′It is expressed as follows:
Wherein, k '=0,1 ..., N-1；
Time domain data { the y that inverse fast Fourier transform (IFFT) is generated is carried out to N subcarriersnIt is expressed as follows:
yn=IFFT { ck′}
Wherein, n=0,1 ..., N-1.
Beneficial effects of the present invention are as follows:
(1) orthogonal frequency division multiplexing (OFDM) and wavelength-division multiplex (WDM) technology are quoted light passive access network by the present invention (PON), using discrete Fourier transform spread spectrum, the PAPR of signal can be reduced, and improves optical receiver sensitivity and ODN Loss budget；Meanwhile compared with prior art, the utilization of frequency band is improved under the premise of the present invention is with less increase operand Rate reduces system cost, effectively improves communication system performance；
(2) real multiplications needed for the algorithm that DFT-S computation complexity of the invention DFT-S OFDM symbol executes Number is balanced, compared to traditional OFDM-WDM-PON method, DFT-S OFDM-WDM-PON method transmitting terminal increase M point from Fourier transformation DFT and (N-M) point subcarrier maps (zero padding) are dissipated, increases corresponding inverse process part in receiving end；M point The conventional method computation complexity of FFT/IFFT isAnd DFT-S OFDM symbol is M 16QAM signal warp After crossing the FFT of M point, spread by subcarrier maps (zero padding) to N point IFFT, so using DFT-S OFDM-WDM-PON method Computation complexity isPass through the comparison of the two computation complexities, it can be seen that DFT-S OFDM-WDM-PON method computation complexity only increasesBut it realizes and PAPR is effectively reduced.
Invention is further described in detail with reference to the accompanying drawings and embodiments, but a kind of use DFT of the invention expands The OFDM-WDM-PON method and system that frequency technology reduces PAPR are not limited to the embodiment.
Detailed description of the invention
Fig. 1 is the DFT-S part-structure block diagram of the embodiment of the present invention；
Fig. 2 is optical line terminal (OLT) block diagram of the embodiment of the present invention；
Fig. 3 is optical network unit (ONU) block diagram of the embodiment of the present invention；
Fig. 4 is the structural block diagram of the embodiment of the present invention；
Attached drawing mark: 1, downlink data signal source；2, serial/parallel conversion；3, QAM modulation；4, M point DFT；5, subcarrier reflects It penetrates；6, N point IFFT；7, add cyclic prefix；8, D/A switch；9, DFT-S OFDM downstream analog signal；10 (1), first laser Device；10 (2), second laser；11, MZ Mach-Zehnder；12, coupler；13, bandpass filter；14, two pole of photoelectricity Pipe；15, low-pass filter；16, OFDM demodulation；17, DFT-S OFDM upstream data；18, upstream data signals source.
Specific embodiment
With reference to the accompanying drawing, technical solution of the present invention is specifically described.
On the one hand, referring to FIG. 1 to FIG. 4, the embodiment of the present invention proposes a kind of using DFT spread spectrum reduction PAPR's OFDM-WDM-PON method, includes the following steps:
S101 uses DAC and FPGA to combine and generates pseudo-random binary bit stream (PRBS) as original binary bit Signal source, i.e. downlink data signal source 1 are flowed, and carries out serial/parallel conversion 2 and obtains the lower sub- bit stream of the road M rate；
Sub- bit stream is carried out 16QAM modulation 3, then carries out M point DFT4, that is, pass through leaf transformation in M point discrete Fourier by S102 New data symbol is generated, data after treatment carry out subcarrier maps 5 and complete spread processing, then carry out N point IFFT6, i.e., N point quick Fourier inversion process is carried out, and adds cyclic prefix 7, after carrying out D/A switch 8, obtains DFT-S 16QAM-OFDM downstream analog signal 9；
S103, the optical line termination parts in entire OFDM-WDM-PON system, by MZ Mach-Zehnder 11, DFT-S 16QAM-OFDM downstream analog signal 9 is loaded on the light carrier of the different wave length of first laser device 10 (1) generation；
DFT-S 16QAM-OFDM downstream analog signal 9 is carried out 15km standard single-mode fiber in optical line terminal by S104 It is transmitted to the coupler 12 of receiving end；
Signal is respectively transmitted to the light unit network of corresponding wavelength, in each light unit by S105 by coupler 12 In network, DFT-S 16QAM-OFDM downstream analog signal passes through bandpass filter 13, filters out the influence of other signals, then passes through Photodiode 14 is crossed, photoelectric conversion is progress OFDM demodulation 16, i.e., in analog signal progress after electricity DFT-S OFDM electric signal After analog/digital conversion obtains digital signal, carry out including cyclic prefix, the transformation of N point quick Fourier (FFT), M point discrete Fourier In leaf transformation (IDFT), demapping and it is parallel/serial conversion etc. a series of Digital Signal Processing, finally recover transmission it is original under Row data signal source 1.
The method also includes:
S201 uses DAC and FPGA to combine and generates pseudo-random binary bit stream (PRBS) as original binary bit Signal source, i.e. upstream data signals source 18 are flowed, and carries out serial/parallel conversion 2 and obtains the lower sub- bit stream of the road M rate；
Sub- bit stream is carried out 16QAM modulation 3, then carries out M point DFT4, that is, pass through leaf transformation in M point discrete Fourier by S202 New data symbol is generated, data after treatment carry out subcarrier maps 5 and complete spread processing, then carry out N point IFFT6, i.e., N point quick Fourier inversion process is carried out, and adds cyclic prefix 7, after carrying out D/A switch 8, obtains DFT-S OFDM upstream data 17；
S203, in different light unit network ONU, by MZ Mach-Zehnder 11 by DFT-S processing DFT-S OFDM upstream data 17 is loaded on the light carrier of the different wave length of second laser 10 (2) transmitting；
S204, multichannel are loaded with the different wave length optical signal of the DFT-S OOFDM signal of the upstream data coupling at coupler 12 It closes, and optical line terminal is transferred to by 15km standard single-mode fiber；
DFT-S OFDM upstream data signals are transmitted to optical line terminal OLT by coupler by S205, at optical link end In end, DFT-S OFDM upstream data signals pass through bandpass filter 13, filter out the influence of other signals.Pass through photodiode After 14, DFT-S OFDM upstream data signals are transformed into electric DFT-S ofdm signal, after low-pass filter 15, carry out OFDM Demodulation 16 carries out including cyclic prefix, quick Fu of N point that is, after analog signal progress analog/digital conversion obtains digital signal In a series of Digital Signal Processing such as leaf transformation (IDFT), demapping and parallel/serial conversion in leaf transformation (FFT), M point discrete Fourier, Finally recover upstream data signals source 18.
On the other hand, a kind of OFDM-WDM-PON system that PAPR is reduced using DFT spread spectrum of the present invention, comprising:
Downlink data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit Stream, i.e. downlink data carry out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and pass through quadrature amplitude modulation 16QAM is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Downlink DFT-S16QAM-OFDM signal acquisition module, for carrying out M point to the M subcarriers for carrying 16QAM signal Discrete Fourier transform DFT carries out zero padding to the N-M subcarriers for not carrying signal come after completing spread spectrum, to N subcarriers into Row inverse fast Fourier transform IFFT adds cyclic prefix CP, carries out parallel/serial conversion and D/A switch, obtain this group of downlink DFT-S16QAM-OFDM signal；
Downlink signal modulation and recovery module, are used in optical line terminal OLT, by this group of downlink DFT-S 16QAM- Ofdm signal is loaded into the light carrier of the different wave length of the generation of the first laser device in OLT by MZ Mach-Zehnder MZM On, to obtain the DFT-S 16QAM-OOFDM signal of corresponding wavelength；By ODN acceptance of the bid quasi-monomode fiber SSMF transmission and divide The DFT-S 16QAM-OOFDM signal of corresponding wavelength is transferred to corresponding optical network unit ONU by road coupler respectively；It is corresponding The DFT-S 16QAM-OOFDM signal of wavelength becomes electric DFT-S 16QAM-OFDM signal, signal after photodiode PD After analog/digital conversion and serial/parallel conversion, cyclic prefix CP is gone, it is discrete successively to carry out N point quick Fourier transformation FFT and M point Inverse Fourier transform IDFT, QAM demapping finally recovers the binary system of the downlink data of original transmitted by parallel/serial conversion Bit stream.
Preferably, the system also includes:
Upstream data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit Stream, i.e. upstream data carry out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and pass through quadrature amplitude modulation 16QAM is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Uplink DFT-S 16QAM-OFDM signal acquisition module, for carrying out M to the M subcarriers for carrying 16QAM signal Leaf transformation DFT in point discrete Fourier, after completing spread spectrum to the N-M subcarriers progress zero padding for not carrying signal, to N subcarriers Inverse fast Fourier transform IFFT is carried out, cyclic prefix CP is added, carries out parallel/serial conversion and D/A switch, obtain this group of uplink DFT-S 16QAM-OFDM signal；
Uplink signal modulation and recovery module, in different optical network unit ONUs, by uplink DFT-S16QAM- Ofdm signal is loaded on the light carrier of the different wave length of second laser transmitting by MZ Mach-Zehnder MZM；Pass through Photo-coupler and standard single-mode fiber SSMF to optical line terminal OLT, distinguish the DFT-S optical signal transmission of uplink in the olt The signal loaded on the light carrier of different wave length is handled, corresponding DFT-S OOFDM signal is become by photodiode PD Electric DFT-S ofdm signal after serial/parallel conversion, removes cyclic prefix CP, successively carries out in quick Fu of N point by analog/digital conversion In leaf transformation FFT and M point discrete Fourier after leaf inverse transformation IDFT, QAM demapping, original transmitted is recovered using parallel/serial conversion Upstream data binary bit stream.
Preferably, downlink signal modulation and recovery module in, to carry 16QAM signal M subcarriers carry out M point it is discrete The frequency domain sample data A generated after Fourier transformation DFTkIt is expressed as follows:
Wherein, xmIndicate M original input data, m=0,1 ..., M-1, k=0,1 ..., M-1；J indicates imaginary number list Position；
To the N subcarriers frequency domain sample data c after (N-M) subcarriers zero paddingk′It is expressed as follows:
Wherein, k '=0,1 ..., N-1；
Time domain data { the y that inverse fast Fourier transform (IFFT) is generated is carried out to N subcarriersnIt is expressed as follows:
yn=IFFT { ck′}
Wherein, n=0,1 ..., N-1.
The above is only a preferable embodiments in present example.But the present invention is not limited to above-mentioned embodiment party Case, it is all by the present invention any equivalent change and modification done, generated function without departing from this programme range when, It belongs to the scope of protection of the present invention.

Claims (6)

1. a kind of OFDM-WDM-PON method for reducing PAPR using DFT spread spectrum characterized by comprising
Step 101, pseudo-random binary bit stream is generated as original binary bit stream, i.e. downlink data, carries out serial/parallel turn Change, make all the way bit stream be divided into M way bit stream, and the mutually orthogonal son in the road N is mapped to by quadrature amplitude modulation 16QAM and is carried On wave；Wherein, N > M；
Step 102, leaf transformation DFT in M point discrete Fourier is carried out to the M subcarriers for carrying 16QAM signal, to not carrying signal N-M subcarriers carry out zero padding to carry out inverse fast Fourier transform IFFT, addition circulation to N subcarriers after completing spread spectrum Prefix CP carries out parallel/serial conversion and D/A switch, obtains this group of downlink DFT-S 16QAM-OFDM signal；
Step 103, in optical line terminal OLT, this group of downlink DFT-S 16QAM-OFDM signal is passed through into mach zhender tune Device MZM processed is loaded on the light carrier of the different wave length of the generation of the first laser device in OLT, to obtain the DFT- of corresponding wavelength S 16QAM-OOFDM signal；By ODN acceptance of the bid quasi-monomode fiber SSMF transmission and shunting coupler, by the DFT-S of corresponding wavelength 16QAM-OOFDM signal is transferred to corresponding optical network unit ONU respectively；The DFT-S 16QAM-OOFDM signal of corresponding wavelength Become electric DFT-S 16QAM-OFDM signal after photodiode PD, signal after analog/digital conversion and serial/parallel conversion, Cyclic prefix CP is gone, leaf inverse transformation IDFT, QAM demapping in N point quick Fourier transformation FFT and M point discrete Fourier is successively carried out, The binary bit stream of the downlink data of original transmitted is finally recovered by parallel/serial conversion.
2. the OFDM-WDM-PON method according to claim 1 for being reduced PAPR using DFT spread spectrum, feature are existed In, further includes:
Step 201, pseudo-random binary bit stream is generated as original binary bit stream, i.e. upstream data, carries out serial/parallel turn Change, make all the way bit stream be divided into M way bit stream, and the mutually orthogonal son in the road N is mapped to by quadrature amplitude modulation 16QAM and is carried On wave；Wherein, N > M；
Step 202, leaf transformation DFT in M point discrete Fourier is carried out to the M subcarriers for carrying 16QAM signal, to not carrying signal N-M subcarriers carry out zero padding to carry out inverse fast Fourier transform IFFT, addition circulation to N subcarriers after completing spread spectrum Prefix CP carries out parallel/serial conversion and D/A switch, obtains this group of uplink DFT-S 16QAM-OFDM signal；
Step 203, in different optical network unit ONUs, uplink DFT-S 16QAM-OFDM signal is passed through into mach zhender Modulator MZM is loaded on the light carrier of the different wave length of second laser transmitting；Pass through photo-coupler and standard single-mode fiber SSMF by the DFT-S optical signal transmission of uplink to optical line terminal OLT, in the olt respectively handle different wave length light carrier on Corresponding DFT-S OOFDM signal is become electric DFT-S ofdm signal by photodiode PD, passed through by the signal of load Analog/digital conversion, after serial/parallel conversion, removes cyclic prefix CP, successively carries out N point quick Fourier and converts FFT and M point discrete Fourier In after leaf inverse transformation IDFT, QAM demapping, recover the binary system ratio of the upstream data of original transmitted using parallel/serial convert Spy's stream.
3. the OFDM-WDM-PON method according to claim 1 for being reduced PAPR using DFT spread spectrum, feature are existed In in step 102, the frequency domain for generate after leaf transformation DFT in M point discrete Fourier to the M subcarriers for carrying 16QAM signal is adopted Sample data AkIt is expressed as follows:
Wherein, xmIndicate M original input data, m=0,1 ..., M-1, k=0,1 ..., M-1；J indicates imaginary unit；
To the N subcarriers frequency domain sample data c after (N-M) subcarriers zero paddingk′It is expressed as follows:
Wherein, k '=0,1 ..., N-1；
Time domain data { the y that inverse fast Fourier transform (IFFT) is generated is carried out to N subcarriersnIt is expressed as follows:
yn=IFFT { ck′}
Wherein, n=0,1 ..., N-1.
4. a kind of OFDM-WDM-PON system for reducing PAPR using DFT spread spectrum characterized by comprising
Downlink data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit stream, i.e., Downlink data carries out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and reflected by quadrature amplitude modulation 16QAM It is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Downlink DFT-S 16QAM-OFDM signal acquisition module, for carry 16QAM signal M subcarriers carry out M point from Fourier transformation DFT is dissipated, after completing spread spectrum to the N-M subcarriers progress zero padding for not carrying signal, N subcarriers are carried out Inverse fast Fourier transform IFFT adds cyclic prefix CP, carries out parallel/serial conversion and D/A switch, obtain this group of downlink DFT- S 16QAM-OFDM signal；
Downlink signal modulation and recovery module, in optical line terminal OLT, this group of downlink DFT-S 16QAM-OFDM to be believed Number by MZ Mach-Zehnder MZM be loaded into the first laser device in OLT generation different wave length light carrier on, thus Obtain the DFT-S 16QAM-OOFDM signal of corresponding wavelength；By ODN acceptance of the bid quasi-monomode fiber SSMF transmission and branch coupling The DFT-S 16QAM-OOFDM signal of corresponding wavelength is transferred to corresponding optical network unit ONU by device respectively；Corresponding wavelength DFT-S 16QAM-OOFDM signal becomes electric DFT-S 16QAM-OFDM signal after photodiode PD, signal by mould/ After number conversion and serial/parallel conversion, cyclic prefix CP is gone, successively carries out leaf in N point quick Fourier transformation FFT and M point discrete Fourier Inverse transformation IDFT, QAM demapping finally recovers the binary bit stream of the downlink data of original transmitted by parallel/serial conversion.
5. the OFDM-WDM-PON system according to claim 4 for being reduced PAPR using DFT spread spectrum, feature are existed In, further includes:
Upstream data generates and modulation module, for generating pseudo-random binary bit stream as original binary bit stream, i.e., Upstream data carries out serial/parallel conversion, make all the way bit stream be divided into M way bit stream, and reflected by quadrature amplitude modulation 16QAM It is mapped on the mutually orthogonal subcarrier in the road N；Wherein, N > M；
Uplink DFT-S 16QAM-OFDM signal acquisition module, for carry 16QAM signal M subcarriers carry out M point from Fourier transformation DFT is dissipated, after completing spread spectrum to the N-M subcarriers progress zero padding for not carrying signal, N subcarriers are carried out Inverse fast Fourier transform IFFT adds cyclic prefix CP, carries out parallel/serial conversion and D/A switch, obtain this group of uplink DFT- S 16QAM-OFDM signal；
Uplink signal modulation and recovery module, in different optical network unit ONUs, by uplink DFT-S 16QAM-OFDM Signal is loaded on the light carrier of the different wave length of second laser transmitting by MZ Mach-Zehnder MZM；Pass through optocoupler Clutch and standard single-mode fiber SSMF to optical line terminal OLT, handle the DFT-S optical signal transmission of uplink respectively in the olt Corresponding DFT-S OOFDM signal is become electricity by photodiode PD by the signal loaded on the light carrier of different wave length DFT-S ofdm signal after serial/parallel conversion, removes cyclic prefix CP, successively carries out N point quick Fourier by analog/digital conversion It converts in FFT and M point discrete Fourier after leaf inverse transformation IDFT, QAM demapping, recovers original transmitted using parallel/serial conversion The binary bit stream of upstream data.
6. the OFDM-WDM-PON system according to claim 4 for being reduced PAPR using DFT spread spectrum, feature are existed In in downlink signal modulation and recovery module, to leaf transformation in the M subcarriers progress M point discrete Fourier for carrying 16QAM signal The frequency domain sample data A generated after DFTkIt is expressed as follows:
Wherein, xmIndicate M original input data, m=0,1 ..., M-1, k=0,1 ..., M-1；J indicates imaginary unit；
To the N subcarriers frequency domain sample data c after (N-M) subcarriers zero paddingk′It is expressed as follows:
Wherein, k '=0,1 ..., N-1；
Time domain data { the y that inverse fast Fourier transform (IFFT) is generated is carried out to N subcarriersnIt is expressed as follows:
yn=IFFT { ck′}
Wherein, n=0,1 ..., N-1.
CN201910511634.6A 2019-06-13 2019-06-13 The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum Pending CN110289886A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910511634.6A CN110289886A (en) 2019-06-13 2019-06-13 The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910511634.6A CN110289886A (en) 2019-06-13 2019-06-13 The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum

Publications (1)

Publication Number Publication Date
CN110289886A true CN110289886A (en) 2019-09-27

Family

ID=68004388

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910511634.6A Pending CN110289886A (en) 2019-06-13 2019-06-13 The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum

Country Status (1)

Country Link
CN (1) CN110289886A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113489546A (en) * 2021-06-29 2021-10-08 上海电力大学 Multi-user dual-band transceiver design method suitable for PON system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090180778A1 (en) * 2008-01-04 2009-07-16 Icu Research And Industrial Cooperation Group Forward Discrete/Inverse-Discrete Fourier Transform Device and Method for Optical OFDM Communication and Transmitting and Receiving Apparatus Comprising the Device
CN101557271A (en) * 2009-04-21 2009-10-14 清华大学 High speed full optical Orthogonal Frequency Division Multiplexing system and method thereof
CN102077536A (en) * 2008-07-08 2011-05-25 高通股份有限公司 Methods and systems for reducing papr of an OFDM signal
CN105245482A (en) * 2015-10-03 2016-01-13 上海大学 OFDM-PON uplink time synchronization method
CN106656334A (en) * 2017-01-12 2017-05-10 中天宽带技术有限公司 Coherent optical orthogonal frequency division multiplexing based long-distance passive optical network system, method for phase noise compensation in coherent optical orthogonal frequency division multiplexing based long-distance passive optical network and application thereof
CN108965188A (en) * 2018-06-27 2018-12-07 华侨大学 The method and system of optical millimeter wave section ofdm signal PAPR are reduced using DFT spread spectrum

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090180778A1 (en) * 2008-01-04 2009-07-16 Icu Research And Industrial Cooperation Group Forward Discrete/Inverse-Discrete Fourier Transform Device and Method for Optical OFDM Communication and Transmitting and Receiving Apparatus Comprising the Device
CN102077536A (en) * 2008-07-08 2011-05-25 高通股份有限公司 Methods and systems for reducing papr of an OFDM signal
CN101557271A (en) * 2009-04-21 2009-10-14 清华大学 High speed full optical Orthogonal Frequency Division Multiplexing system and method thereof
CN105245482A (en) * 2015-10-03 2016-01-13 上海大学 OFDM-PON uplink time synchronization method
CN106656334A (en) * 2017-01-12 2017-05-10 中天宽带技术有限公司 Coherent optical orthogonal frequency division multiplexing based long-distance passive optical network system, method for phase noise compensation in coherent optical orthogonal frequency division multiplexing based long-distance passive optical network and application thereof
CN108965188A (en) * 2018-06-27 2018-12-07 华侨大学 The method and system of optical millimeter wave section ofdm signal PAPR are reduced using DFT spread spectrum

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113489546A (en) * 2021-06-29 2021-10-08 上海电力大学 Multi-user dual-band transceiver design method suitable for PON system

Similar Documents

Publication Publication Date Title
CN103840882B (en) The transmission of fiber optic network, reception, communication system and signal modulator approach
CN102036135B (en) Orthogonal frequency division multiple access (OFDMA) passive optical network transmission system
JP5404925B2 (en) Optical communication system, optical receiver, optical transponder, wavelength division multiplexing optical communication system, wavelength division multiplexing receiver, and wavelength division multiplexing optical transponder
CN103297169B (en) OFDM-PON long-distance transmission method based on comb-shaped light source regeneration technology
CN102231648B (en) Single-carrier-and-multi-carrier-based hybrid transmission system
CN110535803A (en) A kind of passive optical network uplink transmission receiving end demodulation method
CN104010233A (en) Polarization multiplexing coherent detection passive optical network based on ROSA
Qiu et al. OFDM-PON optical fiber access technologies
CN113315581B (en) Microwave photon single optical frequency comb OFDM transmitting device and transmitting method
CN113315582B (en) Microwave photon double-optical-frequency comb OFDM (orthogonal frequency division multiplexing) transmitting device and transmitting method
CN102710996B (en) Method and device for realizing passive ONU (optical network unit) in multi-user OFDM-PON (orthogonal frequency division multiplexing-passive optical network)
CN110289886A (en) The OFDM-WDM-PON method and system of PAPR are reduced using DFT spread spectrum
CN102638310B (en) OFDM-PON (orthogonal frequency division multiplexing-passive optical network) system without optical source and radio frequency source in optical network unit
CN104363532B (en) The method and system of colourless unglazed optical network unit is used in Optical Access Network
EP3016303B1 (en) Method, device, and system for sending and receiving signal
CN103873410B (en) The transmission of OFDM-PON systems and clock signal and extracting method
CN104936047A (en) Uplink system of PON (Passive Optical Network) of filter based multicarrier modulation technology
Luo The application of OFDM in optical fiber communication systems
CN103516428A (en) Optical fiber transmission system and method
CN104935384B (en) The OQAM OFDM wave stack PON downlink transmission systems modulated based on subcarrier
CN101945079A (en) Device for generating, sending and receiving high-order light OFDM-NMSK (Orthogonal Frequency Division Multiplexing-NMSK) signal
CN205378159U (en) Passive optical network system that OCDMA and OFDM mix
CN115189715B (en) Optical transmission device and method based on direct spread spectrum time division multiplexing
CN105578316B (en) OCDMA and OFDM mixed passive optical network system
CN102638312A (en) Coherent optical reception method and device based on orthogonal reference symbols

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20190927