Transport of multiple asynchronous data streams using higher order modulation
20 claims: 9 independent, 11 dependent
- 1光伝送器であって、 モジュールを備え、前記モジュールは、 複数のN個の非同期データストリームから得られる複数のフレームを受信するよう構成され、前記複数のフレームは前記非同期データストリームのフレーミング情報が除去され、前記モジュールはさらに、 共通のクロックを同期の参照として用いて、前記複数のフレームを再フレーミングして、複数の同期したデータストリームを得、前記同期したデータストリームのうちの1つ以上の選択された同期したデータストリームを、 一意的なビットシーケンス でタギングするよう構成され、前記光伝送器はさらに、 前記タギングされた同期したデータストリームを含む前記同期したデータストリーム を 2 N レベルで光変調を実行するように構成された変調器を含む、光伝送器。
- 2前記変調器が前記2 N レベルの光変調を行う前に、前記同期したデータストリームに結び付けられる信号の位相および振幅のうちの少なくとも1つをエンコードするように構成される差動エンコーダをさらに備える、請求項1に記載の光伝送器。
- 3前記同期したデータストリームの偏光多重化、副搬送波多重化、および時分割多重化のうちの少なくとも1つを行うマルチプレクサをさらに備える、請求項1または2に記載の光伝送器。
- 4前記 一意的なビットシーケンス は、受信器における回復のために所与のタギングしたデータストリームを識別するために用いられる 、 請求項1から3のいずれか1項に記載の光伝送器。
- 5前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス を用いて、受信器における受信で、前記同期したデータストリームの1つ以上のタギングされていない同期したデータストリームを識別し抽出する、請求項1から4のいずれか1項に記載の光伝送器。
- 6前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス はフレームプリアンブルに配置される 、 請求項1から5のいずれか1項に記載の光伝送器。
- 7光受信器への伝送に先立ち、1つ以上の他の光信号で前記変調器からの信号を多重化するための波長分割マルチプレクサをさらに備える、請求項1から6のいずれか1項に記載の光伝送器。
- 8光伝送に先立ってデータを処理する方法であって、 複数のN個の非同期データストリームから得られる複数のフレームを受信することを含み、前記複数のフレームは前記非同期データストリームのフレーミング情報が除去され、前記方法はさらに、 共通のクロックを同期の参照として用いて、前記複数のフレームを再フレーミングして、複数の同期したデータストリームを得ることと、 前記同期したデータストリームのうちの1つ以上の選択された同期したデータストリームを、 一意的なビットシーケンス でタギングすることと、 前記タギングされたストリームを含む前記同期したデータストリーム を 2 N レベル で 光変調を実行して、高次変調信号を生成することを含む、方法。
- 9前記2 N レベルの光変調を行う前に、前記同期したデータストリームに結び付けて信号の位相および振幅のうちの少なくとも1つで、前記同期したデータストリームに差動エンコーディングを行うことをさらに備える、請求項8に記載の方法。
- 10前記同期したデータストリームの多重化を行うことをさらに備え、前記多重化は、偏光多重化、副搬送波多重化、および時分割多重化うちの少なくとも1つを含む、請求項8または9に記載の方法。
- 11前記 一意的なビットシーケンス は、受信器における回復のために所与のタギングしたデータストリームを識別するために用いられる 、 請求項8から10のいずれか1項に記載の方法。
- 12前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス を用いて、受信器における受信で、前記同期したデータストリームの1つ以上のタギングされていない同期したデータストリームを識別し抽出する、請求項8から11のいずれか1項に記載の方法。
- 13前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス はフレームプリアンブルに配置される 、 請求項8から12のいずれか1項に記載の方法。
- 14光受信器であって、 光受信器モジュールを備え、前記光受信器モジュールは、 遠隔の光伝送器から複数のN個の同期したデータストリームを受信するよう構成され、前記複数の受信された同期したデータストリームは 一意的なビットシーケンス でタギングされた1つ以上のデータストリームを含み、前記光受信器モジュールはさらに、 前記タギングされたデータストリームを含む前記受信された同期したデータストリーム上において2 N レベルの光変調を実行して、受信されたセットのストリームを得るよう構成され、前記光受信器はさらに、 前記 一意的なビットシーケンス を用いて、前記受信されたセットのストリームをデコードし、デコードしたストリームを生成するように構成されるデコーダと、 前記デコードしたストリームを再フレーミングするための少なくとも1つのモジュールと、を備える、光受信器。
- 15前記光受信器は、前記再フレーミングする前に、前記デコードしたストリームにタグ識別および再順序付けを実行するように構成される、請求項14に記載の光受信器。
- 16前記光受信器モジュールは、前記受信したタギングされて同期したデータストリームから差動位相情報を抽出するために、バランスド光検出器で直接検出を行うようさらに構成される、請求項14または15に記載の光受信器。
- 17前記光受信器モジュールは、前記受信したタギングされた同期したデータストリームから位相状態を抽出するために、コヒーレント検出を行うよう構成される1つ以上のローカル発振器を含む、請求項14から16のいずれか1項に記載の光受信器。
- 18前記 一意的なビットシーケンス は、前記光受信器における回復のために所与のタギングされたデータストリームを識別するために用いられる 、 請求項14から17のいずれか1項に記載の光受信器。
- 19前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス を用いて、前記光受信器における受信で、前記同期したデータストリームの1つ以上のタギングされていない同期したデータストリームを識別し抽出する、請求項14から18のいずれか1項に記載の光受信器。
- 20前記光受信器は、前記タギングされた同期したデータストリームの前記 一意的なビットシーケンス を用いて、前記タギングされていない同期したデータストリームを、前記タギングされたストリームと前記タギングされていないストリームとの間の既知の位相関係に基いて識別および抽出するように構成される、請求項19に記載の光受信器。
Independent claims20
56 paragraphs, as filed
0001(Cross-reference of related applications) This application was filed on April 19, 2011, with US Application No. 13 / 089,437, Title "Transport Of Multipl Using Higher-Order Modulation" e Asynchronous Data s Using Higher Order Modulation) Therefore, all the contents of this disclosure shall be incorporated into this application.
00021. Technical field of the present invention The present invention generally relates to optical transmission systems. More specifically, the feature of the present invention is higher order modulation. Is related to the transmission of multiple asynchronous data streams via an optical transmission system using To. 2. Prior art Many existing networking scenarios use the available fiber optic spectrum Various locations, such as across metropolitan or rural networks, in a way that optimizes Needs to carry many data streams from routers or switches to the logical realm To do. The input data streams are generally non-identical because they come from different independent sources. In the period, it is generally out of phase, and the clock rate is within +/- 100ppm. There is.
0003Some solutions are to synchronize slow services and transmit at high data transfer speeds. For example, Synchronous Optical Network (SONET) / Synchronous Digital Hierarchy (SDH) ) Or Time Division Multiplexing (TDM) using Optical Transmission Network (OTN) Hierarchy adopt. Another solution is to map different input data streams to different wavelengths. Adopt wavelength division multiplexing (WDM), which multiplexes, multiplexes, and sends to a single fiber.
0004In TDM, the input asynchronous data stream is mapped to the transport container and T DM is multiplexed to create a high-speed container. This fast container (stream) is a simple Transmission using various optical modulation techniques from on-off keying to high-order modulation based on phase and polarization Will be sent. However, TDM is the fastest electronic transmission, reception, channel failure, and available. Limited by effective processing technology. Therefore, a serious flaw in TDM-only transmission is Cost, complexity, and load power for the TDM multiplexing stage and subsequent deserialization Power consumption is included. In general, the TDM aggregate approach is by speeding up. Not only high optical and electronic costs, but also complexity due to additional multiplexing / separation May cause sickness.
0005On the other hand, conventional WDM technology (including high-density WDM "DWDM") is used for these low-speed asynchronous transmissions. When used in the same way, the spectral efficiency is very low. Therefore, the total transmission capacity of the optical fiber It may not be possible to use it.
0006The features of the present invention are optical and electro due to the high speed associated with the TDM approach. High nics cost and complexity, and spectral inefficiency of WDM due to slow signal approach It addresses sexual issues. As explained here, the spectrally efficient high-speed screen It can be a trate and is inexpensive in terms of optics and electronics. It is possible to maintain a low speed baud rate.
0007In an embodiment of the invention, a plurality of data streams are transmitted in an optical transmission system. Higher-order variations such as phase modulation and / or amplitude modulation that realize multiple bits per symbol for Providing a key. Additional multiplexing techniques such as time division multiplexing, polarization multiplexing, and subcarrier multiplexing The technique can be used in combination with this higher order modulation. This is a spectrally efficient machine It can be combined in various ways to realize the Luci data stream transmission mechanism. Wear.
0008According to one embodiment, the optical transmission system has multiple N asynchronous data streams. To perform unframing by removing framing information from, and not It contains at least one module for synchronizing the period data stream. This shi Stem also encoded and for reframing synchronized data streams At least one mod for tagging a data stream synchronized with stream information Equipped with a tool. The system also receives light from tagged, synchronized data streams. 2 tagged synchronized data streams prior to transmission to the credit device<sup>N</sup>Light modulation at level It is equipped with a high-order modulator that can be used.
0009As an embodiment, the system has at least one reframing and tagging. Further equipped with a differential encoder to receive a synchronized data stream from the module To do. This differential encoder has 2 higher order modulators<sup>N</sup>Synchronized prior to optical modulation at level Encode at least one of the phase and amplitude of the signal for the data stream It is possible to operate for.
0010As another embodiment, the system is polarized multiplexing of a tagged synchronized data stream. , A multiplexer that performs at least one of subcarrier multiplexing and time division multiplexing. To be equipped.
0011One option is a small number of unframing and synchronization modules At least one manipulates the asynchronous data stream of the first set to synchronize the first set. First set of unframing modules and synchronization modules for creating data streams Manipulating Joule and the second set of asynchronous data streams to manipulate the second set of synchronous data A second set of unframing modules and synchronization modules for making tastreams It is equipped with a tool. Here, among the reframing module and the tagging module At least one of the corresponding ones of the first set of synchronous data streams And re-set the first set to create a tagged synchronous data stream for the first set Framing and tagging modules and a second set of synchronized data strikes A second set of tagged synchronous data stories by manipulating the corresponding one of the reams A second set of reframing and tagging modules to make Equipped. Higher-order modulators have 2 in the first set of tagged synchronized data streams.<sup>N</sup>With the first higher-order modulator to create the first light-modulated signal by performing level light modulation 2 to the second set of tagged synchronized data streams<sup>N</sup>Perform level optical modulation It is provided with a second higher-order modulator for producing a second light-modulated signal. Multipre The kusa receives the first light-modulated signal and the second light-modulated signal, performs polarization multiplexing, and performs polarization multiplexing. It is possible to operate to generate a single multiplexed optical signal prior to transmission to the optical receiver.
0012Another option is the unframing module and the synchronization module. At least one manipulates the asynchronous data stream in the first set to do the same in the first set First set of unframing modules and synchronization modules for creating period data streams Manipulating Joule and the second set of asynchronous data streams to manipulate the second set of synchronous data A second set of unframing and synchronization modules for making tastreams It is equipped with. Here, at least one reframing module and tagging module The tool manipulates the corresponding of the first set of synchronous data streams to make the first First set of reframes to create a tagged synchronous data stream for a set of A second set of synchronized data streams with the tagging and tagging modules A second set of tagged synchronized data streams by manipulating our corresponding ones With a second set of reframing modules and tagging modules to make Prepare. Higher-order modulators have 2 in the first set of tagged synchronized data streams.<sup>N</sup>Re A first higher-order modulator that performs bell light modulation to produce a first light-modulated signal, and a second set of 2 to a tagged synchronized data stream<sup>N</sup>Level light modulation was performed and a second light modulation was performed. It is equipped with a second higher-order modulator that produces a signal. The multiplexer is the first photomodulated signal Receives the second light-modulated signal, performs subcarrier multiplexing, and prior to transmission to the optical receiver It is possible to generate a single multiplexed optical signal.
0013As an additional option, at least one unframing module and synchronization module The tool is equipped with a plurality of unframing modules and a synchronization module, and a plurality of modules are provided. Each of the unframing module and the synchronization module has a corresponding set of asynchronous data. It is configured to manipulate the data stream to create the corresponding set of synchronous data streams. To. At least one reframing module and tagging module can have multiple reframes It is equipped with a raming module and a tagging module. Multiple reframing modules Each of the modules and tagging modules manipulates the corresponding one of the synchronous data streams. It is configured to create and create a corresponding tagged synchronous data stream. here, The multiplexer includes a plurality of time division multiplexers. Each of the time division multiplexers They multiplex a set of tagged synchronous data streams to generate a time division multiplexing signal. To do. The higher order modulator receives a time division multiplexing signal from multiple time division multiplexers, 2<sup>N</sup>It is possible to perform level optical modulation.
0014As another example, the system has at least one module in an asynchronous data story. N asynchronous data streams prior to unframing and synchronizing It further comprises a plurality of photoelectric converters that convert and convert an optical signal into an electric signal. Further As an embodiment, the system is of higher order with one or more other optical signals prior to transmission to the optical receiver. It further comprises a wavelength splitting multiplexer for multiplexing the signal from the modulator. See you again As an example consisting of, the higher order modulator uses phase shift keying or rectangular amplitude modulation 2<sup>N</sup>It is possible to perform level optical modulation.
0015According to another embodiment, the optical transmission method of data is a plurality of N asynchronous data stories. Unframed in each of the steps to receive the stream and multiple N asynchronous data streams Steps to do this, and steps to synchronize multiple N asynchronous data streams. A structured transmission with a tag to identify one or more specific ones of the data stream. Reframing and reframing synchronized data streams to map data to rams 2 to tagging steps and reframing, tagging and synchronizing data streams<sup>N</sup>With the steps of creating a high-order modulated signal that is configured to perform level optical modulation and transmit it to the optical receiver. , Equipped with.
0016As an example, this method is 2<sup>N</sup>Synchronized data before performing level optical modulation Synchronized data with at least one of the phase and amplitude of the signal tied to the trim It further comprises a step of performing differential encoding on the trim.
0017As another example, this method reframed and tagged synchronized data. It further comprises a step of multiplexing the trime. Here, at least bias towards multiplexing Includes at least one of optical multiplexing, subcarrier multiplexing, and time division multiplexing.
0018One option is to use unframing and synchronization to create a first set of synchronized data. Generate a stream and a second set of synchronous data streams. Reframing and ta Reframe from the first set of synchronous data streams to the first set by ging Create a tagged and tagged synchronous data stream and create a second set of synchronous data streams Create a second set of reframed and tagged synchronous data streams from the .. 2<sup>N</sup>For level optical modulation, the first set of reflakes to produce the first higher-order modulated signal Steps to perform higher order modulation on a synchronized data stream that is muted and tagged, and a second To a second set of tagged synchronized data streams to produce a higher-order modulated signal of It includes steps to perform higher order modulation. And for multiplexing, before transmitting to the optical receiver First higher-order modulated signal and second higher-order modulated signal to generate a single multiplexed optical signal Includes the step of performing polarization multiplexing.
0019Another option is to use unframing and synchronization to desynchronize the first set. Generate a data stream and a second set of synchronous data streams. Reframing and And tagging from the first set of synchronous data streams to the first set of reflaming Create a mined and tagged synchronous data stream and create a second set of synchronous data streams A second set of reframed, reframed and tagged synchronized data stories Make a mu. 2<sup>N</sup>For level optical modulation, the first set, to produce the first higher-order modulated signal, Higher-order modulation of a reframed and tagged synchronized data stream And a second set of tagged synchronized data strikes to create a second higher-order modulated signal The ream includes a step of performing higher order modulation. And for multiplexing, it is transmitted to the optical receiver To generate a single multiplexed optical signal, the first higher-order modulated signal and the second higher-order The modulated signal includes a step of performing subcarrier multiplexing.
0020As a further option, by unframing and synchronization, the first set of synchronization days Generate a tastream and a second set of synchronous data streams. Reframing and Reframe from the first set of synchronous data streams to the first set by tagging Create a tagged and tagged synchronous data stream and create a second set of synchronous data streams A second set of reframed and tagged synchronized data streams from the stream make. For multiplexing, the first photomodulated signal is used to generate the first time division multiplexing signal. A step of performing the first time division multiplexing and a second to generate a second time division multiplexing signal. The photomodulated signal includes a second time division multiplexing step. And 2<sup>N</sup>level For optical modulation of, the first time division multiplexing signal and the second time division multiplexing signal are 2<sup>N</sup>Perform optical modulation Includes steps.
0021As another embodiment, this method further precedes unframing and synchronization. It comprises the steps of converting N asynchronous data streams from optical signals to electrical signals. Sa As another embodiment, this method further comprises one or more other lights before transmitting to the optical receiver. A step of performing wavelength division multiplexing on a high-order modulated signal of a signal is provided. And as another example 2<sup>N</sup>Level optical modulation employs phase shift keying or rectangular amplitude modulation.
0022As a further embodiment, the optical transceiver is a plurality of N asynchronous data streams. To perform unframing by removing framing information from, and asynchronous dede It contains at least one module for synchronizing the data stream. Also this The transceiver reframes and encodes the synchronized data stream. At least one module for tagging data streams synchronized with stream information And the synchronized synchronization that was tagged before transmitting the synchronized synchronized data stream to the optical receiver. 2 of the data stream<sup>N</sup>It is equipped with a high-order modulator capable of performing level optical modulation. .. The transceiver also has synchronized data tagged from a remote higher order modulator. Tagging received to receive a stream and output a set of received streams Light capable of performing at least one of demodulation and detection of synchronized data streams A receiver module and a stream that decodes and decodes the set of received streams Deframing a decoder that can generate a stream and reframing the decoded stream It comprises at least one module for the purpose.
0023As an example, this optical transceiver also reframes the decoded stream. To identify and reorder the decoded streams by tags before teaming It is equipped with the means of. As another embodiment, this optical transceiver also receives a story. Signal tuning the set of received streams to eliminate transmission failures in the set of streams Provide means to do so. As yet another embodiment, this optical receiver module receives Balun to extract differential phase information from a tagged synchronized data stream It can be detected directly with a photodetector. And, as another embodiment, the optical receiver mod The tool extracts the phase state from the received tagged synchronized data stream. Therefore, one or more local oscillators capable of coherent detection are included.
0024<figref num="1">It illustrates a typical optical transceiver structure according to the features of the present invention.</figref><figref num="2">It illustrates the conversion from a plurality of asynchronous data streams to synchronous streams according to the features of the present invention.</figref><figref num="3">It illustrates the use of polarization multiplexing and subcarrier multiplexing with higher order modulation according to the features of the present invention.</figref><figref num="4">It illustrates the time division multiplexing with higher order modulation according to the features of the present invention.</figref><figref num="5A">It illustrates the constellation when using typical high-order modulation according to the features of the present invention.</figref><figref num="5B">It illustrates the constellation when using typical high-order modulation according to the features of the present invention.</figref><figref num="6">It illustrates one method of identifying a frame using embedded tags, which is a feature of the present invention.</figref><figref num="7">It illustrates a second method of identifying a frame using an embedded tag, which is a feature of the present invention.</figref><figref num="8">It illustrates a system using 16-QAM higher order modulation according to the features of the present invention.</figref><figref num="9">It illustrates a typical rectangular 16-QAM transmitter configuration according to the features of the present invention.</figref><figref num="10">It illustrates a typical star-shaped 16-QAM transmitter configuration according to the features of the present invention.</figref><figref num="11">It illustrates the operation of a typical transmitter and receiver according to the features of the present invention.</figref>
0025The features, properties, and advantages of the present invention will be considered with reference to the following embodiments and attachments. You can understand by doing. If the same reference number is used in different drawings, it will be the same or similar. Identify similar components. Furthermore, the following description does not limit the present invention, but the present invention. The technical scope of is defined by the appended claims and their equivalents.
0026As presented herein, the optical system according to the embodiment of the present invention has a plurality of bits for each symbol. Higher-order modulation is used to transmit the signal. This system restores the data stream at the receiver Adopt a differential encoding with a data stream identifier to source. Details below As mentioned, direct detection with a balanced receiver or coffee with an optical local oscillator Both rent detections can be used in the receiver.
0027FIG. 1 is a block diagram illustrating an optical transceiver system 100 according to the features of the present invention. To. System 100 has multiple low-speed client signals on the input side and DWDM on the output side. Adopt a high-speed signal with one wavelength. As shown in this embodiment, a plurality of N asynchronous devices The data stream is input to system 100. For example, each stream is R Gigabit A given data transfer rate of / second, generally within the difference of +/- 100ppm, N Each data stream can have slightly different data transfer speeds .. These N streams pass through the payload level unframing module 102 Then, it is synchronized with the synchronization block 104. Unframing module 102 is inf Remove iniband, Ethernet, or SONET framing. Data stream Are aligned at synchronization block 104. For transmission scenarios that employ synchronization, Synchronization block 104 transfers all streams at the same data rate for all transmissions. It can be retimed with the same reference clock as it does. Unframing and And synchronization can be done separately or simultaneously on the same or different devices. Unflami Module 102<sub>1</sub>~102<sub>N</sub>Before being received by the converter, the data stream is Jules 105<sub>1</sub>~105<sub>N</sub>Can be converted from an optical signal to an electric signal. these The converter module 105 receives the input stream as an electrical signal instead of an optical signal. If so, it can be omitted.
0028At the same time, the stream is reframed with one or more framing modules 106. , Tagged at block 108 to restore the data in the stream. Fremin Module 106 adds information such as headers or markers to the stream. The ging block 108 encodes the stream information. Reframing and tagging Can be performed separately or simultaneously on the same device or on different devices. Framing In the action and tagging section, the input client data is a structured fixed size. The function to map to the transmission frame and the header information are added. This header information As part of the information, tags are added to identify a particular client stream. This The tag is used to restore the client stream at the receiver location.
0029The stream then goes to the differential encoder 110, which encodes the signal phase and / or amplitude. It is preferable to be sent. Data so that the receiver can restore the data stream It is preferable to perform differential encoding using the stream identifier. Data story The identifier is a simple 3-bit or 4-bit buy, for example 100 or 1011. It can be a Naricode. The differentially encoded signal is then an optical modulator. Sent to complex 112. Here, for example, gray coding is applied to the n-level modulated signal. By using, individual stream data can be mapped to multiple construction points. Be ping. These constructions (representing a combination of amplitude modulation and phase modulation) Each of these is modulated into a carrier wave generated by a sustained wave (CW) laser 114. Multiple instances of a modulated optical signal at DWDM wavelength over a fiber optic cable Multiplexed together for transmission.
0030As an example, higher order modulation uses 16QAM to transmit 4 bits / symbol. In this example, the symbol (baud) rate is 10 Gb / s at a bit rate of 40 Gb / s. can do. This allows a single WDM wavelength and a 50 GHz wavelength grid. Can transmit four 10Gb / s data streams. Therefore, this system is expensive Allowing fast bit rates for spectral efficiency while maintaining slow baud rates it can. In the other examples described below, higher order modulation is combined with one or more additional modulation schemes. Can be used together. These include polarization multiplexing, subcarrier multiplexing, and intermediate TDM. Includes multiplexing.
0031In the receiver shown in FIG. 1, the DWDM signal is an optical receiver that acts as a demodulator and / or detector. Input to the device module 116. As one embodiment, the receiver module 116 is the difference. Direct detection can be performed with a balanced photodetector to extract dynamic phase information. Other fruits As an example, the receiver module 116 presents in an optical hybrid to extract the phase state. Field oscillator-based synchronous detection can be employed. Module 116 is a digital communication Clean the signal with or without termination by the No. Processor (DSP) Can be used to
0032Signal conditioner 118 can be included as part of system 100. This If included, the signal conditioner 118 eliminates transmission failures such as dispersion. Used to compensate for obstacles after the signal has crossed the fiber. Signal conde The conditioner 118 may include, for example, a finite impulse response (FIR) filter or a maximum likelihood estimator ( It is desirable to include color dispersion compensation, phase and polarization restoration using MLSE). this Is performed using a known adaptive equalization algorithm. The resulting stream is de Decoded by coder 120. Reframing is an individual reframing module Le 122<sub>1</sub>~122<sub>N</sub>Is done by. At this time, identification and / or reordering is blocked. Runs at 124. Tag identification and reordering (if necessary) is a reframing process Can be executed before is done. Reframing, tagging, and reordering It can be done separately or simultaneously on the same device or different devices. Next, the electric / optical converter Module 126<sub>1</sub>~126<sub>N</sub>Sends signals to downstream equipment (not shown) to N optical data. It can be used to convert to a stream. Alternatively, a system with downstream electrical signals The optical converter module 126 can be omitted when it is sent to the module.
0033According to the above description, FIG. 2 shows a plurality of asynchronous data streams 202.<sub>1</sub>~202<sub>N</sub>Higher order change It illustrates a typical system 200 for transmitting as a tonal optical signal. Figure Wavelength multiplexing of multiple modulated signals (N streams) before transmission over fiber optics Shows the change. Separation of the asynchronous clock area and the synchronous clock area extends to the PHY layer frame. And / or remapping asynchronous data streams to MAC layer frames (eg Lock 204<sub>1</sub>~204<sub>N</sub>It is executed by performing the unframing shown in (1), and then Then, using the common reference clock 208 as the synchronous reference signal, synchronous reframing ( For example, block 206<sub>1</sub>~206<sub>N</sub>Framing and tagging as shown in) Will be done.
0034Then, for example, as described for the modulator complex 112 in FIG. 1, synchronous data storage. The boom is modulated by multi-level modulation in block 210. N synchronous bits About<sup>N</sup>The symbol modulation scheme then 2<sup>N</sup>Symbol-modulated stri Treat each of the sync streams as one of the N-bit symbols mapped to the stream Is used so that These modulated streams are even more numerous in the wavelength region. It can be carried at a predetermined carrier wavelength for overlaying. Additional multiplexing The resulting optical signal is added to the WDM multiplexed signal before transmission, as shown in block 212. be able to. The reverse processing is used for the received signal and the asynchronous data stream 202<sub>1</sub>~202<sub>N</sub>Is obtained.
0035As mentioned above, additional modulation schemes can be adopted with higher order modulation. Figure 3 Combines higher order modulation with a second orthogonal multiplexing method (eg, polarization multiplexing or subcarrier multiplexing) Provides a typical configuration 300 to let. In this embodiment, polarization multiplexing or secondary transport The clock regions for transmission multiplexing can be completely independent. For example, each block 302<sub>1</sub>And 302<sub>2</sub>Two sets of streams processed by (1)<sub>1</sub>From 1<sub>N</sub>And 2<sub>1</sub>Or 2<sub>N</sub>) Is shown. When the unframing process is complete, the top set Stream (1<sub>1</sub>~1<sub>N</sub>) Is the first common clock 304<sub>1</sub>Has a lower set of stories Mu (2<sub>1</sub>~2<sub>N</sub>) Is the second common clock 304<sub>2</sub>Will have. 1st common cross It is desirable that the clock and the second common clock are independent of each other. For example, the clock , Can be selected based on the card for each line. Each line card is generally one Or it means two wavelengths.
0036The stream set transmission and reception processes shown in FIG. 3 are further multiplexed as described below. As a condition, it is possible to proceed as described above for FIGS. 1 and 2. On the transmission side, Figure 2 Block 210 and FIG. 1 Optical modulator complex 112, respectively. 306<sub>1</sub>And 306<sub>2</sub>By, once a separate stream set (1<sub>1</sub>~1<sub>N</sub>And 2<sub>1</sub>From 2<sub>N</sub>When processed, they are blocked, for example by polarization multiplexing or subcarrier multiplexing. Multiplexed together at 308. Polarization multiplexing uses a polarized beam combiner (PBC) Can be done. Subcarrier multiplexing is a subcarrier comb (rather than a DWDM grid) (The space is rather small), but it is multiplexed using a modulator connected in series and RF, and from RF Performed by FPGA or ASIC or other mechanism that converts to light and modulates the laser source Can be done. The resulting output from block 308 is a multiplexed optical signal, followed by And is sent to the WDM multiplexer 310. Here, with WDM multiplexer 212 Similarly, additional multiplex optical signals can be added and the resulting optical stream will be Transmission is possible via an optical cable (not shown). On the receiving side, the reverse processing is performed, and the optical cable The input from the bull is WDM demultiplexed and the additional multiplexed optical signal is depolarized or subcarriers Remove before desorption.
0037Subcarrier multiplexing in this embodiment can employ cooperative transport or multiplex transport. Wear. Combined light spectrum, although additional transmitters and receivers are used with subcarrier modulation Can be transmitted through a single ITU grid window and even more spectrally It can be made more efficient. The total number of supported data streams is the number of subcarriers ( For example, it increases by the same number as 2).
0038Figure 4 shows a typical system that includes a combination of higher order modulation and an intermediate TDM multiplexing stage. Shows 400. In this embodiment, the TDM stage uses a common clock 2 Synchronize and multiplex two input streams. As shown, the system 400 is the system of FIG. It has the same configuration as the system 200. Where asynchronous stream 402<sub>1</sub>,402<sub>2</sub>,・・・ ,402<sub>N</sub>Unframed using the timing from the common local clock 408 Processed by the ng module 404 and the framing / tagging module 406, paired It becomes a pair of corresponding synchronous streams. At block 410, before modulation with multi-level modulation , Each pair of sync streams is in each block 412 to generate a multiplexed signal Time division multiplexing is performed.
0039Intermediate TDM multiplexing stage (block 412)<sub>1</sub>~412<sub>N</sub>), Many input days Increase the data transfer rate so that it can support data streams. For example , With symbol velocity R just by using higher order modulation 2<sup>N</sup>The size of the construction Each supports N streams operating at R data transfer speeds. Intermediate TD By using the M stage in this embodiment, the symbol speed of the output signal is increased to R * T. Add. Where T is the number of data streams multiplexed in the intermediate TDM stage. Yes, the total number of supported data streams is N * T. Equally (or alternative) , Reduce the intermediate stage to the size of the construction. In this example, the data strike Reems are TDM-multiplexed together at block 412, but with additional streams added You can also do it. For example, 4 or more streams can be multiplexed together. And As described above for the WDM multiplexer 212, the result is an additional multiplexed optical signal. Before transmitting the resulting optical stream as a WDM multiplexer 414 Can be done.
0040We have described several different configurations, but any combination of properties here is of higher order. It can be used with modulation. As an example, the system may be combined with higher order modulation. And include any or all of polarization multiplexing, subcarrier multiplexing, and TDM multiplexing. Can be done. In addition, the plurality of streams formed by such processing are wavelength division multiplexing. Can be combined using chemicals.
0041Due to the various combinations mentioned above, some methods require synchronization, while others So synchronization is not necessary. The present invention relates to either a synchronous mapping method or an asynchronous mapping method. It can also be used in combination of such methods. Table 1 below shows the various multiplexing methods and pieces. Indicates whether each stream needs to be synchronized.<img id="000002" he="36" wi="144" file="JP6139639B2_D0001.tif" img-format="tif" img-content="drawing" /> Table 1 Multiplexing method and synchronization According to one feature of the present invention, the format of the construction used for higher-order modulation is Arayu. Not only can it be shaped, but it can also be any combination of phase and amplitude. is there. Typical construction is QPSK or 8-P for phase only modulation SK is included and 16-QAM is included for phase and amplitude modulation. Construction As an example of the modification of the shape of, there is a star-shaped construction or a rectangular construction. Figure Two forms of 16-QAM construction are illustrated in 5A and 5B. 5A shows a star-shaped construction, and Figure 5B shows a rectangular construction. As a matter of course, the x-axis and the y-axis can be rotated by the rotation of the phase during transmission. Tagi Can be used to deal with this, and the receiver can use which stream of tag information. Used to decide whether to encode. Tagging will be described in detail below.
0042The size of the construction can be arbitrary and the link of the input data stream It can be made dependent on the size of the aggregation (LAG). For example, (4 bits / 16-QAM (symbol) 1 for each modulated signal operating at 40 Gb / s It can be used to carry four data streams running at 0b / s. Similarly , 256-QAM (8 bits / symbol) to modulated signal operating at 80Gb / s On the other hand, it can be used for 8 data streams running at 10b / s each.
0043The modulation scheme described above on the transmission side is the equivalent demodulation at the receiver to complete the transmission link. / Combined with separation. In the main method of adopting the above-mentioned higher-order modulation, the receiver circuit is field-generated. Adopt either direct detection without a shaker or coherent detection with a field oscillator Can be done. Various possibilities are described below.
0044One option is to detect directly without a signal to process the block. In one embodiment By the way, this allows for proper optical performance without the additional signal to process the block. This is a preferred embodiment in terms of cost and power efficiency. In this approach, the field oscillator Is not used. Instead, it restores the relative phase state, which results in a differential encoding of the phase state. Adopt direct detection to extract the signal. For example, a balanced photodetector, difference It can be used to extract phase information.
0045Another option is to detect directly using a signal processing block. Now process the block Backend signals with phase restoration, wavelength dispersion and polarization dispersion compensation, and non-linear effects and polarization Used for partial purification of noise. This signal processing block is an analog block However, it can also be implemented as a digital block. Digital signal processing block Is accompanied by analog / digital (A / D).
0046The third option uses a field oscillator with a signal processing block. In this case, from the site The tremor is via a 90 degree hybrid complex using homodyne or heterodyne technology. By combining the field oscillator with the input signal, coherent detection of the input signal is possible. To. Such an extracted state is a signal processing such as a DSP backend for signal purification. It can be post-processed using a physical block.
0047As mentioned above, tagging is done after unframing, as shown in FIG. Main departure According to one feature of Ming, it is unique for identifying and restoring the data stream at the receiver. The method used to tag a bit sequence into one or all data streams Be done. In a preferred embodiment where the system performs relative phase restoration rather than absolute phase restoration. This method of tagging is used to identify the restored data stream. Modulated ski One or more (data) to allow identification and restoration of the data stream, depending on the data stream. Tag the data stream (up to the maximum number of streams).
0048Figure 6 shows that if the relative phase of the data stream is preserved during transmission, it is embedded in the channel. It illustrates one way to identify a frame using a sewn tag. This scenario In the identification of one data stream, the data streams are known to be fixed to each other. Is sufficient to identify and extract the remaining data stream .. One way to incorporate an identification tag is to have a unique bit sequence in the frame preamble. Is to use. All data streams with higher order modulation are frame synced All data streams can be identified using this method.
0049Higher-order modulation approaches (eg, polarization multiplexing, subcarrier multiplexing, and intermediate TDM multiplexing) As another example associated with ), the relationships between individual data streams are known and therefore And when the relationships between individual data streams can be saved, the same taguin as above The data stream can be restored and properly identified using the procedure. Multiplex ski There is no need to add additional tags for each page.
0050Figure 7 illustrates an alternative way to identify frames using tags embedded in channels. I understand it. Here, the relative phase of the data stream is not stored during transmission. this Because in the scenario the data streams do not have known relationships that are fixed to each other To identify and extract the remaining data stream (between 1 and N depending on the modulation scheme) It is necessary to identify all or one or more data streams.
0051As mentioned above, different higher order modulation techniques can be adopted for the different configurations shown here. To. Four asynchronous data with 16-QAM modulation with the overall configuration shown in Figure 2. It illustrates a concrete example of multiplexing streams. And Figure 9 shows the 16-QAM quadrature. An example of the transmitter embodiment 900 of the form construction is shown. Here, 4 encodings Data stream 902<sub>1</sub>~902<sub>4</sub>Is a table like A, B, C, and D, respectively. It has been forgotten. The beam from laser 904 is split and modulator (M) 906<sub>1</sub>~90 6<sub>4</sub>Will be sent to. As one embodiment, the modulator 906 is a Mach Zenda modulator (MZM). ). As shown, the lower branch of the laser signal is due to the attenuator 908 or a lower spray. It is attenuated by a splitter with a ratio. In this case, the lower branch is phase modulation and amplitude Since it is a combination of modulation, the lower branch is attenuated. Positioned by Mach Zenda modulator Phase modulation is performed and the attenuator provides the required amplitude damping. This means that the four points are on the top Shown by the lower "Cross" diagram shown to have an amplitude smaller than the four points in the "Cross" diagram of Has been done.
0052Modulator 906<sub>1</sub>And 906<sub>1</sub>The signal output from is in phase (I), while the modulator 90 6<sub>2</sub>And 906<sub>4</sub>The signal output from is shifted by 90 degrees (Quadrature). (Q). As shown, the I and Q components from the upper branch are the first construction. And the I and Q components from the lower branch have a second construction, resulting in The resulting construction will be a rectangle 16-QAM.
0053FIG. 10 shows an embodiment of a 16-QAM star-shaped construction transmitter Example 1000. An example is shown. Here, four encoded data streams 1002<sub>1</sub>~1002<sub>4</sub>Are shown as A, B, C, and D, respectively. Beam from laser 1004 Is split into four modulators (M) 1006<sub>1</sub>~1006<sub>4</sub>Will be sent to. One example As the modulator 1006, it is a Machzenda modulator. The resulting constellation The session will be a 16-QAM star as shown.
0054Figure 11 shows a typical system level application 1100. Transmitter side 110 In 2, the group of slow data streams has a single DWDM wavelength with higher order modulation. Mapped to. On the receiver side 1104, the input higher-order modulated signal is frame-removed (d). e-framed) and join the group of slow data streams.
0055The present invention has been described with reference to specific embodiments, but of course these embodiments The state merely shows the principle and application examples of the present invention. Therefore, of course Et al., Without departing from the spiritual and technical scope of the invention as defined in the appended claims. Many changes can be made to the embodiments shown, and other configurations can be modified. Wear.
0056The present invention includes, and is limited to, an optical communication system that employs higher-order modulation techniques. It has wide industrial applicability.
12 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8 Sheet 9 Sheet 10 Sheet 11 Sheet 12
Every citation, both ways
| Document | Relation | Office |
|---|---|---|
| WO2009001437A1 | Cites | World Intellectual Property Organization (WIPO) |
| JP2010050803A | Cites | Japan |
| Milorad Cvijetic,Technologies and Practical Aspects of Next Generation Optical Networking,11th International Conference on Transparent Optical Networks, 2009. ICTON '09.,米国,IEEE,2009年 6月28日,P. 1-4 | Non-patent | – |
28 members in 9 offices
Members28
| Document | Office | Kind | |
|---|---|---|---|
| US2012269512A1 | United States of America | A1 | |
| CA2832915A1 | Canada | A1 | |
| WO2012145165A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2012145165A3 | World Intellectual Property Organization (WIPO) | A3 | |
| EP2700182A2 | European Patent Office (EPO) | A2 | |
| KR20140030198A | Republic of Korea | A | |
| CN103650396A | China | A | |
| US8712251B2 | United States of America | B2 | |
| JP2014518601A | Japan | A | |
| US2014219655A1 | United States of America | A1 | |
| EP2700182A4 | European Patent Office (EPO) | A4 | |
| US8909064B2 | United States of America | B2 | |
| JP5843336B2 | Japan | B2 | |
| CA2832915C | Canada | C | |
| JP2016076943A | Japan | A | |
| CN103650396B | China | B | |
| CN106209248A | China | A | |
| KR101690035B1 | Republic of Korea | B1 | |
| KR20170002671A | Republic of Korea | A | |
| DE202012013446U1 | Germany | U1 | |
| JP6139639B2This record | Japan | B2 | |
| KR101743133B1 | Republic of Korea | B1 | |
| CN106209248B | China | B | |
| EP2700182B1 | European Patent Office (EPO) | B1 | |
| DK2700182T3 | Denmark | T3 | |
| EP3471300A1 | European Patent Office (EPO) | A1 | |
| EP3471300B1 | European Patent Office (EPO) | B1 | |
| DK3471300T3 | Denmark | T3 |
17 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Written notification of registration of transferJAPANESE INTERMEDIATE CODE: R350R350 | R350 | |
| Written request for registration of change of nameJAPANESE INTERMEDIATE CODE: R313533S533 | S533 | |
| Certificate of patent or registration of utility modelJAPANESE INTERMEDIATE CODE: R150R150 | R150 | |
| First payment of annual fees (during grant procedure)JAPANESE INTERMEDIATE CODE: A61A61 | A61 | |
| Written decision to grant a patent or to grant a registration (utility model)JAPANESE INTERMEDIATE CODE: A01A01 | A01 | |
| Decision of grant or rejection writtenTRDD | TRDD | |
| Request for written amendment filedJAPANESE INTERMEDIATE CODE: A523A521 | A521 | |
| Request for written amendment filedJAPANESE INTERMEDIATE CODE: A523A521 | A521 | |
| Notification of reasons for refusalJAPANESE INTERMEDIATE CODE: A131A131 | A131 | |
| Report on retrievalJAPANESE INTERMEDIATE CODE: A971007A977 | A977 |
Numbers
- Publication
- 6139639
- Application
- 222089
Titles2
- Japanese
- 高次変調を用いた複数の非同期データストリームの伝達
- English
- Transmission of multiple asynchronous data streams using higher-order modulation
Classification
- CPC, 18
- H04B10/5051
- H04J14/06
- H04Q11/0005
- H04B10/5053
- H04B10/5161
- H04B10/541
- H04B10/5561
- H04J3/04
- H04J3/0602
- H04J14/0279
- H04J3/0685
- H04J14/0298
- H04L27/34
- H04L27/36
- H04J14/08
- H04J14/03
- H04Q2011/0045
- H04Q2213/13361
- IPC, 4
- H04J14 08
- H04J3 00
- H04B10 516
- H04L27 00
