技术领域technical field
本发明涉及光纤通信技术领域，尤其涉及一种提高多载波光源载噪比的方法。The invention relates to the technical field of optical fiber communication, in particular to a method for improving the carrier-to-noise ratio of a multi-carrier light source.
背景技术Background technique
随着全球宽带业务流量的迅速增长，特别是视频类业务如SDTV（StandardDefinitionTelevision，标清晰电视）、HDTV（HighDefinitionTelevision，高清晰电视）、OnlineGame（在线游戏）、VOD（VideoOnDemand，视频点播技术）等的出现，给传输信道容量带来了巨大的压力。目前100Gb/s以太网系统已经成功商用化，下一代通信的紧迫任务就是向着太比特(Tb/s)的以太网传输发展。目前在实现太比特的大容量传输系统的方案中，基于多载波光源的太比特传输系统是一个非常有竞争力的方案。与WDM（Wavelengthdivisionmultiplexing，波分复用）或者DWDM（DenseWavelengthDivisionMultiplexing，密集波分复用系统）相比，基于多载波光源的系统不需要使用数量巨大（数百个）的激光器，同时，由于多载波光源的子载波都是由同一个种子光源产生，子载波之间的性能一致性很好，载波之间没有频率漂移、间隔完全锁定，可以利用多载波光源的这些特性实现超信道(super-channel)传输，达到更高的频谱效率。With the rapid growth of global broadband service traffic, especially video services such as SDTV (Standard Definition Television, standard definition television), HDTV (High Definition Television, high-definition television), OnlineGame (online game), VOD (VideoOnDemand, video on demand technology), etc. Appeared, brought huge pressure to the transmission channel capacity. At present, the 100Gb/s Ethernet system has been successfully commercialized, and the urgent task of the next generation communication is to develop towards Terabit (Tb/s) Ethernet transmission. At present, in the scheme of realizing the large-capacity transmission system of terabit, the terabit transmission system based on the multi-carrier light source is a very competitive scheme. Compared with WDM (Wavelengthdivisionmultiplexing, wavelength division multiplexing) or DWDM (DenseWavelengthDivisionMultiplexing, dense wavelength division multiplexing system), a system based on a multi-carrier light source does not need to use a huge number (hundreds) of lasers. At the same time, due to the multi-carrier light source The sub-carriers are all generated by the same seed light source, the performance consistency between sub-carriers is very good, there is no frequency drift between carriers, and the interval is completely locked. These characteristics of multi-carrier light sources can be used to realize super-channel (super-channel) transmission to achieve higher spectral efficiency.
目前，用于太比特传输系统的频率锁定多载波光源实现方法主要有：电光调制器单次深度调制和循环频移器。基于单个MZM（Mach-ZehnderModulator，马赫-曾德尔调制器）、PM（PhaseModulator，相位调制器）或者级联的MZM+PM的单次深度调制所产生的多载波光源具有很好的稳定性，而且其子载波之间的频率间隔可调谐性好，但是，利用这种方式产生的子载波数目较少，一般在10个左右，多的可以达到30个，光源的载噪比在15～20dB左右。循环频移器是基于IQM（I/QModulator，IQ调制器）、MZM或者PM调制器构成的环状结构的循环调制，其优势是不需要高的驱动电压，具有产生大数目子载波的能力，同时可以控制输出的子波数目及中心频率，平坦度较好；但它需要在环路中使用光放大器来补偿环路中的能量损耗，这样就不可避免的会引入ASE（amplifiedspontaneousemission，放大自发辐射）噪声，并且随着循环次数的增加，噪声会不断累积，导致光源最终输出的载噪比降低。At present, the main implementation methods of frequency-locked multi-carrier light sources used in terabit transmission systems include: electro-optical modulator single-shot deep modulation and cyclic frequency shifter. The multi-carrier light source based on a single deep modulation of a single MZM (Mach-ZehnderModulator, Mach-Zehnder modulator), PM (PhaseModulator, phase modulator) or cascaded MZM+PM has good stability, and The frequency interval between the subcarriers can be tuned well, but the number of subcarriers generated by this method is relatively small, generally around 10, and the number can reach 30, and the carrier-to-noise ratio of the light source is around 15-20dB . The cyclic frequency shifter is a cyclic modulation based on a ring structure composed of IQM (I/QModulator, IQ modulator), MZM or PM modulator. Its advantage is that it does not require high driving voltage and has the ability to generate a large number of subcarriers. At the same time, the number of wavelets and the center frequency of the output can be controlled, and the flatness is good; but it needs to use an optical amplifier in the loop to compensate for the energy loss in the loop, so it will inevitably introduce ASE (amplified spontaneous emission, amplified spontaneous emission) ) noise, and as the number of cycles increases, the noise will continue to accumulate, resulting in a decrease in the carrier-to-noise ratio of the final output of the light source.
目前文献中公开的采用循环频移器产生的多载波光源的载噪比在20dB左右，只能满足PDM（PolarizationDivisionMultiplexing，偏分复用）-QPSK（四相相移键控信号）传输要求。然而，在太比特传输系统中，发射端一般需要采用PDM-16QAM（正交幅度调制）甚至PDM-64QAM格式的高阶调制码型，它们对光源光信噪比的要求分别在20dB及29dB以上，相应的光源载噪比为27dB和36dB。The carrier-to-noise ratio of the multi-carrier light source produced by the cyclic frequency shifter disclosed in the current literature is about 20dB, which can only meet the transmission requirements of PDM (Polarization Division Multiplexing, polarization division multiplexing)-QPSK (quaternary phase shift keying signal). However, in a terabit transmission system, the transmitter generally needs to use high-order modulation patterns in PDM-16QAM (orthogonal amplitude modulation) or even PDM-64QAM format, and their requirements for the optical signal-to-noise ratio of the light source are above 20dB and 29dB respectively , and the corresponding light source carrier-to-noise ratios are 27dB and 36dB.
综上所述，现有技术仍然无法实现大幅度提高载噪比，同时降低引入的ASE噪声。To sum up, the existing technology still cannot achieve a substantial increase in the carrier-to-noise ratio while reducing the introduced ASE noise.
发明内容Contents of the invention
（一）要解决的技术问题(1) Technical problems to be solved
针对上述缺陷，本发明要解决的技术问题是如何在降低放大器引入的放大自发辐射噪声的同时，大幅度提高载噪比。In view of the above defects, the technical problem to be solved by the present invention is how to greatly improve the carrier-to-noise ratio while reducing the amplified spontaneous emission noise introduced by the amplifier.
（二）技术方案(2) Technical solutions
为解决上述问题，本发明提供了一种提高多载波光源载噪比的方法，包括以下步骤：In order to solve the above problems, the present invention provides a method for improving the carrier-to-noise ratio of a multi-carrier light source, comprising the following steps:
S1、在光放大器之后设置时延干涉仪；S1, setting a time-delay interferometer after the optical amplifier;
S2、入射到所述时延干涉仪的信号被分成强度相同的两路，一路为时延路，用于对信号附加时延，另一路为调相路，用于对信号附加相位；S2. The signal incident to the time-delay interferometer is divided into two paths with the same intensity, one is a time-delay path for adding time delay to the signal, and the other path is a phase modulation path for adding phase to the signal;
S3、所述时延路和所述调相路合并，通过选择合适的时延和相移实现对所有子载波中心频率处干涉相长和相邻子载波间中点频率处干涉相消。S3. The time delay circuit and the phase modulation circuit are combined, and the interference construct at the center frequency of all subcarriers and the interference cancellation at the midpoint frequency between adjacent subcarriers are realized by selecting an appropriate time delay and phase shift.
进一步地，所述时延干涉仪为马赫-曾德尔结构。Further, the time-delay interferometer is a Mach-Zehnder structure.
进一步地，所述时延路输出的光信号为其中E(ω)为入射光信号的频域分量，ω为光信号的角频率，τ为所述时延干涉仪中所述时延路的时延大小，且τ＝1/fs，其中fs为载波频率间隔。Further, the optical signal output by the delay path is Where E(ω) is the frequency domain component of the incident optical signal, ω is the angular frequency of the optical signal, τ is the time delay of the time delay path in the time delay interferometer, and τ=1/fs , where fs is the carrier frequency interval.
进一步地，所述调相路输出的光信号为其中为所述调相路的相移。Further, the optical signal output by the phase modulation circuit is in is the phase shift of the phase modulation circuit.
进一步地，所述在所有子载波中心频率处实现干涉相长的条件是其中为所述延时路与所述调相路的相位差，k为非负整数。Further, the condition for achieving interference constructive at all subcarrier center frequencies is in is the phase difference between the delay circuit and the phase modulation circuit, and k is a non-negative integer.
进一步地，所述在相邻子载波间中点频率处实现干涉相消的条件是Further, the condition for achieving interference cancellation at the midpoint frequency between adjacent subcarriers is
进一步地，所述方法适用于环路结构的多载波光源或光频梳。Further, the method is applicable to a multi-carrier light source or an optical frequency comb with a loop structure.
进一步地，所述方法还适用于非环路结构的多载波光源或光频梳。Further, the method is also applicable to multi-carrier light source or optical frequency comb with non-loop structure.
（三）有益效果(3) Beneficial effects
本发明提供了一种提高多载波光源载噪比的方法，该方法既适用于环路结构的多载波光源或光频梳，也适用于非环路结构的多载波光源或光频梳，使用时延干涉仪以达到抑制光放大器产生的放大自发辐射噪声的目的，提高载噪比，可以提高10-15dB，从而为更高速率的网络通信系统实用化提供技术支持，以及提供更好的网络通信质量以及更好的网络可靠率。The present invention provides a method for improving the carrier-to-noise ratio of a multi-carrier light source. The method is not only suitable for a multi-carrier light source or an optical frequency comb with a loop structure, but also for a multi-carrier light source or an optical frequency comb with a non-loop structure. Delay interferometer to achieve the purpose of suppressing the amplified spontaneous emission noise generated by the optical amplifier, improving the carrier-to-noise ratio, which can be increased by 10-15dB, thereby providing technical support for the practical application of higher-speed network communication systems, and providing better network Communication quality and better network reliability.
附图说明Description of drawings
图1为本发明一种提高多载波光源载噪比的方法的步骤流程图；Fig. 1 is a flow chart of the steps of a method for improving the carrier-to-noise ratio of a multi-carrier light source in the present invention;
图2为本发明提供的方法应用在环路结构的多载波光源示意图；Fig. 2 is a schematic diagram of a multi-carrier light source applied to a loop structure by the method provided by the present invention;
图3为本发明提供的方法应用在非环路结构的多载波光源示意图；Fig. 3 is a schematic diagram of a multi-carrier light source applied to a non-loop structure by the method provided by the present invention;
图4为宽光谱光源经过时延干涉仪后输出的频谱图；Figure 4 is a spectrum diagram output by a wide-spectrum light source after passing through a time-delay interferometer;
图5为未使用本实施例提供的时延干涉仪的循环频移器结构的多载波光源输出的频谱图；FIG. 5 is a spectrum diagram of a multi-carrier light source output without using the cyclic frequency shifter structure of the time-delay interferometer provided in this embodiment;
图6为使用本实施例提供的时延干涉仪的循环频移器结构的多载波光源输出的频谱图。FIG. 6 is a spectrum diagram of the multi-carrier light source output using the cyclic frequency shifter structure of the time-delay interferometer provided in this embodiment.
具体实施方式detailed description
下面结合附图和实施例，对本发明的具体实施方式作进一步详细描述。以下实施例用于说明本发明，但不用来限制本发明的范围。The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.
本发明实施例中提供了一种提高多载波光源载噪比的方法，具体流程如图1所示，包括以下步骤：An embodiment of the present invention provides a method for improving the carrier-to-noise ratio of a multi-carrier light source. The specific process is shown in Figure 1, including the following steps:
步骤S1、在光放大器之后设置时延干涉仪，其中时延干涉仪为马赫-曾德尔结构。Step S1, setting a time-delay interferometer after the optical amplifier, wherein the time-delay interferometer is a Mach-Zehnder structure.
本实施例提供的方法不仅适用于环路结构的多载波光源或光频梳，还适用于非环路结构的多载波光源或光频梳，如图2和3所示，其中图2为环路结构的多载波光源，图3为非环路结构（即级联结构）的多载波光源。The method provided in this embodiment is not only applicable to multi-carrier light sources or optical frequency combs with a loop structure, but also applicable to multi-carrier light sources or optical frequency combs with a non-loop structure, as shown in Figures 2 and 3, where Figure 2 is a loop A multi-carrier light source with a loop structure, and Figure 3 shows a multi-carrier light source with a non-loop structure (ie, a cascaded structure).
图2和图3中的调制器组可以为一个IQ调制器或者N个不同调制器的级联。Ubias1,Ubias2……UbiasN为N个不同调制器的偏置电压，URF1,URF2……URFN为N个不同调制的射频驱动电压。一般都会使用光放大器来补偿信号能量损伤以及对载波进行放大，但是在放大过程中会引入ASE噪声。在图2和图3所示的两种结构的多载波光源产生方案中，均是在光放大器之后放置一个MZ（马赫-曾德尔）结构的时延干涉仪，来抑制光放大器引入的ASE噪声，这种方案可以使光源输出的载噪比有很大的提升，其原理在于利用了宽谱光源的频域干涉。The modulator group in FIG. 2 and FIG. 3 may be an IQ modulator or a cascade of N different modulators. Ubias1 , Ubias2 ... UbiasN are the bias voltages of N different modulators, URF1 , URF2 ... URFN are the radio frequency driving voltages of N different modulations. Generally, an optical amplifier is used to compensate signal energy damage and amplify the carrier, but ASE noise will be introduced during the amplification process. In the multi-carrier light source generation schemes of the two structures shown in Figure 2 and Figure 3, a delay interferometer with an MZ (Mach-Zehnder) structure is placed after the optical amplifier to suppress the ASE noise introduced by the optical amplifier , this solution can greatly improve the carrier-to-noise ratio of the output of the light source, and its principle is to utilize the frequency-domain interference of the wide-spectrum light source.
步骤S2、入射到时延干涉仪的信号被分成强度相同的两路，一路为时延路，用于对信号附加时延，另一路为调相路，用于对信号附加相位。In step S2, the signal incident to the time-delay interferometer is divided into two paths with the same strength, one is a delay path for adding time delay to the signal, and the other is a phase modulation path for adding phase to the signal.
在MZ时延干涉仪中，信号被分成两路，其中一路通过一段时延线，其时延大小为子载波频率间隔的倒数，另一路通过某种方式来调整信号的相位。在图2和图3所示的结构中，Udelay用来控制时延，Uphase用来调整相移，分别经过时延和相移的两路光信号再合在一起。最后，时延干涉仪输出的光信号为In the MZ time-delay interferometer, the signal is divided into two paths, one of which passes through a delay line whose time delay is the reciprocal of the subcarrier frequency interval, and the other path adjusts the phase of the signal in some way. In the structures shown in Figure 2 and Figure 3, Udelay is used to control the time delay, Uphase is used to adjust the phase shift, and the two optical signals that have undergone time delay and phase shift respectively are combined together. Finally, the optical signal output by the time-delay interferometer is
不同频率处的信号光强度为The signal light intensity at different frequencies is
其中公式（1）中时延路输出的光信号为调相路输出的光信号为E(ω)为入射光信号的频域分量，ω为光信号的角频率，τ为时延干涉仪中时延路的时延大小，且τ＝1/fs，其中fs为载波频率间隔，其中为调相路的相移。The optical signal output by the delay path in formula (1) is The optical signal output by the phase modulation circuit is E(ω) is the frequency domain component of the incident optical signal, ω is the angular frequency of the optical signal, τ is the time delay of the delay path in the delay interferometer, and τ=1/fs , where fs is the carrier frequency interval, where is the phase shift of the phase modulation circuit.
步骤S3、时延路和调相路合并，通过选择合适的时延和相移实现对所有子载波中心频率处干涉相长和相邻子载波间中点频率处干涉相消。In step S3, the time delay path and the phase modulation path are merged, and the interference constructivity at the center frequency of all subcarriers and the interference cancellation at the midpoint frequency between adjacent subcarriers are realized by selecting an appropriate time delay and phase shift.
对于加入MZ时延干涉仪的多载波光源，在第n个子载波中心频率处两支路的相位差为其中f0为种子光源的中心频率，fs为所加射频信号的频率，即相邻子载波间的频率差。For a multi-carrier light source with an MZ time-delay interferometer, the phase difference between the two branches at the center frequency of the nth subcarrier is Among them, f0 is the center frequency of the seed light source, and fs is the frequency of the added radio frequency signal, that is, the frequency difference between adjacent subcarriers.
如果延时路与调相路的相位差那么在这些频点处的光就会发生干涉相长，而满足的ω处的光就会发生干涉相消。对于宽光谱光源入射的情况，其经过时延干涉仪后输出频谱上会产生周期性的干涉峰，如图4所示。If the phase difference between the delay circuit and the phase modulation circuit Then the light at these frequency points will interfere constructively, and satisfy The light at ω will interfere and destructively. For the incident of a wide-spectrum light source, periodic interference peaks will be generated on the output spectrum after passing through the time-delay interferometer, as shown in Figure 4.
通过选取合适的时延τ和相移来保证从而可以实现每个子载波中心频率处的干涉相长，若选取τ＝1/fs，那么By selecting the appropriate time delay τ and phase shift to guarantee Thus, the interferometric constructivity at the center frequency of each subcarrier can be realized. If τ=1/fs is selected, then
只需调节MZ干涉仪的相移Uphase，使得（m为整数），那么每个子载波的中心频率处就会实现干涉相长。Just adjust the phase shift Uphase of the MZ interferometer so that (m is an integer), then the center frequency of each subcarrier will achieve interference constructive.
相应的，两个子载波之间的频率点ω′＝2πf0+(2n+1)πfs处有Correspondingly, at the frequency point ω′=2πf0 +(2n+1)πfs between two subcarriers, there is
由于之前对相移的设置满足那么在ω′处会出现干涉相消。利用这一特性，可以用来对梳状光源进行滤波，来抑制ASE噪声，并且效果提升明显。Since the previous setting of the phase shift satisfies So Interferometric cancellation occurs at ω′. Utilizing this feature, it can be used to filter the comb light source to suppress ASE noise, and the effect is significantly improved.
图5和图6是在基于循环频移器结构（属于环路结构的多载波光源）的多载波光源中验证了本实施例提供的方法的效果对比，其中图5为未使用本实施例提供的时延干涉仪的循环频移器结构的多载波光源输出，图6为使用了本实施例提供的时延干涉仪的循环频移器结构的多载波光源输出。Figure 5 and Figure 6 are a comparison of the effects of the method provided by this embodiment in a multi-carrier light source based on a cyclic frequency shifter structure (a multi-carrier light source belonging to a loop structure), where Figure 5 is a multi-carrier light source that does not use this embodiment. The output of the multi-carrier light source with the cyclic frequency shifter structure of the time-delay interferometer shown in FIG. 6 is the output of the multi-carrier light source with the cyclic frequency shifter structure of the time-delay interferometer provided by this embodiment.
综上所示，本实施例提供的提高载噪比的方法既适用于环路结构的多载波光源或光频梳，也适用于非环路结构的多载波光源或光频梳，使用时延干涉仪以达到抑制光放大器产生的放大自发辐射噪声的目的，提高载噪比，可以提高10-15dB，从而为更高速率的网络通信系统实用化提供技术支持，以及提供更好的网络通信质量以及更好的网络可靠率。To sum up, the method for improving the carrier-to-noise ratio provided by this embodiment is not only applicable to the multi-carrier light source or optical frequency comb of the loop structure, but also applicable to the multi-carrier light source or optical frequency comb of the non-loop structure. The interferometer is used to suppress the amplified spontaneous emission noise generated by the optical amplifier and increase the carrier-to-noise ratio by 10-15dB, thus providing technical support for the practical application of higher-speed network communication systems and providing better network communication quality and better network reliability.
以上实施方式仅用于说明本发明，而并非对本发明的限制，有关技术领域的普通技术人员，在不脱离本发明的精神和范围的情况下，还可以做出各种变化和变型，因此所有等同的技术方案也属于本发明的范畴，本发明的专利保护范围应由权利要求限定。The above embodiments are only used to illustrate the present invention, but not to limit the present invention. Those of ordinary skill in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all Equivalent technical solutions also belong to the category of the present invention, and the scope of patent protection of the present invention should be defined by the claims.
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310184928.5ACN103326782B (en) | 2013-05-17 | 2013-05-17 | A kind of method improving multicarrier light source carrier-to-noise ratio |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310184928.5ACN103326782B (en) | 2013-05-17 | 2013-05-17 | A kind of method improving multicarrier light source carrier-to-noise ratio |
| Publication Number | Publication Date |
|---|---|
| CN103326782A CN103326782A (en) | 2013-09-25 |
| CN103326782Btrue CN103326782B (en) | 2016-03-30 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310184928.5AExpired - Fee RelatedCN103326782B (en) | 2013-05-17 | 2013-05-17 | A kind of method improving multicarrier light source carrier-to-noise ratio |
| Country | Link |
|---|---|
| CN (1) | CN103326782B (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110011749B (en)* | 2019-04-10 | 2021-02-05 | 中山大学 | A physical layer security communication method based on destructive interference of acoustic waves in multi-carrier modulation |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5373389A (en)* | 1992-10-27 | 1994-12-13 | General Instrument Corporation | Method for linearizing an unbalanced Mach Zehnder optical frequency discriminator |
| US5420868A (en)* | 1992-07-31 | 1995-05-30 | At&T Corp. | Suppression of brillouin scattering in lightwave transmission system |
| CN1264231A (en)* | 1999-02-19 | 2000-08-23 | 朗迅科技公司 | Optical signal transmission method for reducing degenerate caused by non-linear effect |
| US6229632B1 (en)* | 1997-05-12 | 2001-05-08 | Ditech Corporation | Broadband optical transmission system utilizing differential wavelength modulation |
| CN1706128A (en)* | 2003-09-08 | 2005-12-07 | 日本电信电话株式会社 | Optical signal receiver, optical signal receiving apparatus, and optical signal transmitting system |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5420868A (en)* | 1992-07-31 | 1995-05-30 | At&T Corp. | Suppression of brillouin scattering in lightwave transmission system |
| US5373389A (en)* | 1992-10-27 | 1994-12-13 | General Instrument Corporation | Method for linearizing an unbalanced Mach Zehnder optical frequency discriminator |
| US6229632B1 (en)* | 1997-05-12 | 2001-05-08 | Ditech Corporation | Broadband optical transmission system utilizing differential wavelength modulation |
| CN1264231A (en)* | 1999-02-19 | 2000-08-23 | 朗迅科技公司 | Optical signal transmission method for reducing degenerate caused by non-linear effect |
| CN1706128A (en)* | 2003-09-08 | 2005-12-07 | 日本电信电话株式会社 | Optical signal receiver, optical signal receiving apparatus, and optical signal transmitting system |
| Publication number | Publication date |
|---|---|
| CN103326782A (en) | 2013-09-25 |
| Publication | Publication Date | Title |
|---|---|---|
| Pfeifle et al. | Flexible terabit/s Nyquist-WDM super-channels using a gain-switched comb source | |
| CN105099570B (en) | Orthogonal multiple carrier light source and PDM-QPSK sender units | |
| US10044444B2 (en) | Photonic vector signal generation without precoding | |
| US8483575B2 (en) | Apparatus and method for generating frequency-locked optical comb sources | |
| JP2014217053A (en) | Crosstalk reduction in optical network utilizing variable subcarrier spectrum allocation | |
| Peng et al. | Hybrid QAM transmission techniques for single-carrier ultra-dense WDM systems | |
| CN106253992B (en) | A kind of optical frequency comb generation method and its polarized orthogonal single-side band modulating device | |
| CN103229439A (en) | Optical communication system, optical transmitter, and transponder | |
| Li et al. | Phase noise canceled polarization-insensitive all-optical wavelength conversion of 557-Gb/s PDM-OFDM signal using coherent dual-pump | |
| Yu et al. | 30-Tb/s (3× 12.84-Tb/s) signal transmission over 320km using PDM 64-QAM modulation | |
| Zhang et al. | High-spectral-efficiency photonic frequency down-conversion using optical frequency comb and SSB modulation | |
| CN103326782B (en) | A kind of method improving multicarrier light source carrier-to-noise ratio | |
| US8064775B2 (en) | Generation of at least 100 Gbit/s optical transmission | |
| US9094129B2 (en) | Dual-drive modulator | |
| Zhang et al. | Polarization multiplexed OFDM band interleaving enabled metro-access integrated networks | |
| JP6468629B2 (en) | WDM coherent transmission system | |
| Shao et al. | Integrated gain switched comb source for 100 gb/s WDM-SSB-DD-OFDM system | |
| CN115622690B (en) | A local oscillator CV-QKD system and method with no crosstalk of pilot light | |
| CN103716095A (en) | Circulating frequency shift multi-carrier light source generating scheme of additional intensity modulator | |
| CN102780669B (en) | Implementation method and device of all-optical OFDM (Orthogonal Frequency Division Multiplexing) signal photosphere network code | |
| JP7636698B2 (en) | Signal detection device, signal detection method, and program | |
| Xu et al. | Silicon microring IQ modulator enabled single sideband OFDM transmission | |
| JP5385858B2 (en) | Generation method and apparatus for optical orthogonal frequency division multiplexing optical signal | |
| CN102882667B (en) | The multi-carrier generation device with N frequency multiplication single-side belt frequency displacement loop is injected based on N wavelength | |
| Hu et al. | 1.57 Tb/s PDM-layered 80QAM-OFDM in super-channel transmission based on self-homodyne comb |
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee | Granted publication date:20160330 |