WO2022206310A1 - 光发送和光收发组件、光通信设备及光信号的发送方法 - Google Patents

光发送和光收发组件、光通信设备及光信号的发送方法 Download PDF

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Publication number
WO2022206310A1
WO2022206310A1 PCT/CN2022/079749 CN2022079749W WO2022206310A1 WO 2022206310 A1 WO2022206310 A1 WO 2022206310A1 CN 2022079749 W CN2022079749 W CN 2022079749W WO 2022206310 A1 WO2022206310 A1 WO 2022206310A1
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optical
optical signal
wavelength
modulated
bit
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PCT/CN2022/079749
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English (en)
French (fr)
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锁靖
黄禹尧
陈冠儒
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华为技术有限公司
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Publication of WO2022206310A1 publication Critical patent/WO2022206310A1/zh

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    • 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
    • H04B10/572—Wavelength control
    • 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
    • H04B10/40—Transceivers
    • 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
    • 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
    • H04B10/501—Structural aspects
    • H04B10/503—Laser transmitters

Definitions

  • the present application relates to the technical field of optical communication, and in particular, to an optical transmission and optical transceiver assembly, an optical communication device, and an optical signal transmission method.
  • Optical transmission components are mainly used for the transmission of optical signals, and are important components in passive optical networks (PONs).
  • Optical transmission components are used in key equipment in PON systems, such as optical line terminals (OLTs), optical network terminals (ONUs), and so on.
  • Optical transmission components usually include lasers and filtering units.
  • the information carried by the modulated optical signal output by the laser is a binary coded sequence composed of bit 1 and bit 0, and the wavelength corresponding to bit 1 is different from the wavelength corresponding to bit 0.
  • the filtering unit improves the extinction ratio of the laser by filtering out the wavelength corresponding to bit 0 in the modulated optical signal.
  • the filter unit is a band-pass filter unit, and the band-pass filter unit locks the wavelength of the modulated optical signal output by the laser.
  • the wavelength of the modulated optical signal will jitter rapidly, and the filter spectral line of the bandpass filter unit cannot track the wavelength change of the modulated optical signal, resulting in bit 1
  • the attenuation of the modulated optical signal corresponding to the wavelength is too large, which adversely affects the communication quality.
  • the present application provides an optical transmission component, an optical transceiver component, an optical communication device and an optical signal transmission method, which can improve communication quality.
  • the present application provides an optical transmission assembly.
  • the optical transmission assembly includes a first laser and a band-stop filter unit.
  • the first laser is used to output the first modulated optical signal.
  • the information carried by the first modulated optical signal includes bit 0 and bit 1, and the wavelength corresponding to the bit 0 is different from the wavelength corresponding to the bit 1.
  • the band-stop filter unit is configured to lock the wavelength of the first modulated optical signal output by the first laser, so that the lower limit cut-off wavelength in the forward filter spectral line of the band-stop filter unit is within the bit between the peak wavelength corresponding to 0 and the peak wavelength corresponding to the bit 1, so as to filter out the optical signal of the wavelength corresponding to the bit 0 in the received first modulated optical signal, to obtain a second modulated optical signal, and output all the modulated optical signals. the second modulated optical signal.
  • locking the wavelength of the first modulated optical signal output by the first laser by the band-stop filter unit refers to the difference between the first center wavelength and the first center wavelength in the forward filtering spectral line of the band-stop filter unit.
  • the difference between the wavelengths of the modulated optical signals is kept within a certain difference range.
  • the forward filter spectral line refers to the filter spectral line of the optical signal input from the input port of the band-stop filter unit.
  • the band-stop filter unit locks the wavelength of the first modulated optical signal output by the first laser
  • the difference between the first center wavelength and the wavelength of the first modulated optical signal is a fixed value.
  • the wavelength of the first modulated optical signal will change slightly near the target wavelength. Since the band-stop filter unit has no time to respond to the slight change, the first center wavelength of the band-stop filter unit is basically unchanged, and the difference between the first center wavelength and the wavelength of the first modulated optical signal will be within a certain difference range Variety.
  • the forward filter spectral line of the band-stop filter unit has a lower cutoff wavelength and an upper cutoff wavelength.
  • the lower cutoff wavelength and the upper cutoff wavelength are wavelengths that satisfy the following conditions: wavelengths smaller than the lower cutoff wavelength can pass through the bandstop filter unit, wavelengths greater than the upper cutoff wavelength can pass through the bandstop filter unit, and the cutoff at the upper limit The wavelength between the wavelength and the lower cutoff wavelength will be attenuated to a certain extent after passing through the filter unit.
  • the lower cutoff wavelength of the band-stop filter unit is located between the peak wavelength corresponding to bit 0 and the peak wavelength corresponding to bit 1, and the modulation of the wavelength corresponding to bit 1
  • the optical signal can pass through the band-stop filter unit with less attenuation.
  • the spectral peak of the first modulated optical signal will jitter rapidly.
  • the wavelength corresponding to bit 1 always moves within a certain range smaller than the lower cutoff wavelength of the band-stop filter unit. Therefore, even if the band-stop filter unit has no time to follow the waveform of the first modulated optical signal, The wavelength corresponding to bit 1 can still pass through the band-stop filter unit with small attenuation, thereby improving the communication quality.
  • the band-stop filter unit includes a tunable filter.
  • the tunable filter has an input port, a download port, and a pass-through port.
  • the optical transmission assembly further includes an optical power detection unit.
  • the optical power detection unit is used to detect a first optical power and a second optical power, the first optical power is proportional to the optical power of the first modulated optical signal received by the input port, and the second optical power is the optical power of the optical signal of the wavelength corresponding to the bit 0 output by the download port.
  • the tunable filter is configured to adjust the first center wavelength in the forward filter spectral line based on the first optical power and the second optical power.
  • the first center wavelength is adjusted until the ratio of the first optical power and the second optical power is a set value, at this time, the tunable filter locks the first modulated light the wavelength of the signal.
  • the optical signal of the wavelength corresponding to bit 0 is output from the download port, and the second modulated optical signal is output from the through port.
  • the optical power of the optical signal output from the download port has a negative correlation with the wavelength spacing.
  • the wavelength spacing refers to the absolute value of the difference between the first center wavelength of the tunable filter and the wavelength of the optical signal received by the input port. The larger the wavelength spacing, the smaller the optical power of the optical signal output by the download port; the smaller the wavelength spacing, the greater the optical power of the optical signal output by the download port. Therefore, by adjusting the first center wavelength, the optical power of the optical signal output by the download port can be changed.
  • the ratio of the first optical power to the second optical power depends on the magnitude of the second optical power.
  • the ratio of the first optical power to the second optical power is a set value, it indicates that the first center wavelength is at a required wavelength locking position relative to the wavelength of the optical signal received by the input port. Therefore, adjusting the first center wavelength in the forward filtering spectral line based on the first optical power and the second optical power is beneficial for the tunable filtering unit to quickly lock the first modulated optical signal output by the first laser wavelength.
  • the optical power detection unit includes: a beam splitter, a first photodetector, and a second photodetector.
  • the optical splitter is located on the optical path between the first laser and the tunable filter, and is used for dividing the first modulated optical signal into a first optical signal and a second optical signal, and for dividing the first modulated optical signal into a first optical signal and a second optical signal.
  • One optical signal is transmitted to the input port.
  • the first optical detector is used to detect the optical power of the second optical signal to obtain the first optical power.
  • the second light detector is used to detect the second light power.
  • the tunable filter is a reciprocal passive optical device.
  • the reciprocal passive optical device has a simple structure and mature products, which is conducive to popularization and application.
  • the tunable filter is a non-reciprocal passive optical device.
  • the band-stop filter unit is further configured to adjust the second center wavelength in the reverse filtering spectral line, so that the wavelength corresponding to the first modulated optical signal is located in the reverse filtering spectral line of the band-stop filtering unit. between the lower cutoff wavelength and the upper cutoff wavelength to prevent the wavelength corresponding to the first modulated optical signal from passing through the band-stop filter unit in reverse.
  • the band-stop filter unit can also play the role of isolation, without using a separate isolator, so that the optical transmission component contains fewer devices and the structure is simpler.
  • the inverse filtering spectral line refers to the filtering spectral line for the optical signal input from the through port of the band-stop filter unit.
  • the optical transmission component further includes an optical switch, the optical switch is located on the optical path between the band-stop filter unit and the light outlet of the optical transmission component, and the optical switch is used to control the optical switch. Whether the second modulated optical signal output by the band-stop filter unit is output from the light outlet.
  • the optical transmission component is included in the standby passive optical network port of the optical communication device, the first laser can always be in a stable working state.
  • the optical switch is turned off, and the standby passive optical network port does not carry service.
  • the optical switch is turned on and switched to the standby passive optical network port for service bearing. Compared with starting the first laser when network protection is performed, there is no need to wait for the wavelength output by the first laser to stabilize, and the switching time can be reduced.
  • the optical switch includes one input port and two output ports, the input port of the optical switch is used for receiving the second modulated optical signal output by the band-stop filter unit, the two One of the output ports is used to output the second modulated optical signal to the light outlet, and the other of the two output ports is used to output the second modulated optical signal to the outside of the light outlet s position.
  • the optical transmission assembly further includes a third photodetector, the other of the two output ports is coupled to the third photodetector, and the output port coupled to the third photodetector is used for for outputting the second modulated optical signal to the third photodetector.
  • the third light detector detects the light signal, it means that the optical switch is turned off, and when the third light detector does not detect the light signal, it means that the light switch is turned on.
  • the light transmitting assembly includes only one laser. In other examples, the light transmitting assembly includes multiple lasers. For example, in addition to the first laser, the light transmitting assembly also includes a second laser. The second laser is used for outputting a third modulated optical signal.
  • the optical transmission component When the optical transmission component includes multiple lasers, the optical transmission component further includes a wave combiner, which is used for combining the modulated optical signals output by the multiple lasers into a mixed optical signal, and then output from the light output port of the optical transmission component.
  • a wave combiner which is used for combining the modulated optical signals output by the multiple lasers into a mixed optical signal, and then output from the light output port of the optical transmission component.
  • the optical switch has two arrangements. One is that the optical switch is located on the optical path between the band-stop filter unit and the combiner.
  • the combiner is used to combine the second modulated optical signal output by the optical switch and the third modulated optical signal output by the second laser into a mixed modulated optical signal, and output the mixed modulated optical signal to the light outlet .
  • the other is that the optical switch is located on the optical path between the combiner and the optical outlet.
  • the wave combiner is used to combine the second modulated optical signal output by the band-stop filter unit and the third modulated optical signal output by the second laser into a mixed modulated optical signal, and transmit the mixed modulated optical signal to the
  • the optical switch is used to control whether the second modulated optical signal in the mixed modulated optical signal is output from the optical outlet.
  • the light-transmitting assembly further includes a thermoelectric cooler (TEC) on which the first laser and the band-stop filter unit are carried.
  • TEC thermoelectric cooler
  • the temperature of the first laser and the band-stop filter unit can be adjusted simultaneously through the semiconductor refrigerator, so that the wavelength output by the first laser and the first center wavelength of the band-stop filter unit are changed. Since the thermo-optic coefficients of the first laser and the band-stop filter unit are different, under the same temperature change, the wavelength change of the first laser is different from the wavelength change of the first center wavelength. In this way, the wavelength of the first laser and the The difference between the first center wavelengths of the band-stop filter unit changes until the band-stop filter unit locks the wavelength of the first modulated optical signal output by the first laser.
  • TEC thermoelectric cooler
  • the tunable filter is a microring resonator, a microdisk resonator or a Mach-Zehnder interferometer.
  • the present application provides an optical transceiver assembly.
  • the optical transceiver assembly includes an optical receiving assembly and an optical transmitting assembly.
  • the optical transmission component is any of the aforementioned optical transmission components.
  • the wavelength division multiplexing device is configured to transmit the second modulated optical signal output by the optical sending component to the light outlet, and transmit the third modulated optical signal input from the optical outlet to the light receiving component.
  • the light receiving component is used for converting the received third modulated optical signal into an electrical signal.
  • the present application also provides an optical communication device.
  • the optical communication device is an OLT that includes the aforementioned optical transceiver components.
  • the optical communication device is an ONU, and the ONU includes the aforementioned optical transmission components.
  • the optical communication device is an optical module, including the aforementioned optical transmission components or optical transceiver components.
  • the present application also provides a method for sending an optical signal.
  • the method includes: controlling a first laser to output a first modulated optical signal, the information carried by the first modulated optical signal includes bit 0 and bit 1, and the wavelength corresponding to the bit 0 is different from the wavelength corresponding to the bit 1;
  • the wavelength of the first modulated optical signal is locked by a band-stop filter unit, so as to filter the first modulated optical signal.
  • locking means that the difference between the first center wavelength in the forward filtering spectral line of the band-stop filter unit and the wavelength of the first modulated optical signal is kept within a certain difference range, and the The lower limit cutoff wavelength in the forward filter spectral line of the band-stop filter unit is between the peak wavelength corresponding to the bit 0 and the peak wavelength corresponding to the bit 1.
  • the band-stop filter unit can filter out the optical signal of the wavelength corresponding to bit 0 in the received first modulated optical signal, obtain the second modulated optical signal, and output the second modulated optical signal.
  • the band-stop filter unit includes a tunable filter, and the tunable filter has an input port, a download port and a pass-through port.
  • the filtering of the first modulated optical signal by a band-stop filter unit includes: determining a first optical power and a second optical power, and the first optical power is related to the first optical power received by the input port.
  • the optical power of the modulated optical signal is proportional, and the second optical power is the optical power of the optical signal of the wavelength corresponding to the bit 0 output by the download port; based on the first optical power and the second optical power, The first center wavelength in the forward filter spectral line is adjusted, so that the optical signal of the wavelength corresponding to the bit 0 is output from the download port, and the second modulated optical signal is output from the through port.
  • the adjusting the first center wavelength in the forward filter spectral line includes: adjusting the semiconductor refrigerator through the semiconductor refrigerator The temperature of the first laser and the band-stop filter unit to adjust the wavelength of the first modulated optical signal output by the first laser and the first center wavelength, so that the first center wavelength locks the first center wavelength The wavelength of the first modulated optical signal output by a laser.
  • adjusting the first center wavelength of the tunable filter based on the first optical power and the second optical power includes: when the ratio of the first optical power to the second optical power is different When equal to the set value, the first center wavelength of the tunable filter is adjusted so that the ratio of the first optical power to the second optical power changes until the ratio of the first optical power to the second optical power is equal to the set value. In this way, the first center wavelength can be locked to the wavelength of the first modulated optical signal output by the first laser.
  • the band-stop filter unit locks the wavelength of the first modulated optical signal output by the first laser, so as to filter the first modulated optical signal output by the first laser.
  • the wavelength corresponding to bit 1 can always be smaller than the lower cutoff wavelength of the band-stop filter unit. In this way, it can be ensured that the first modulated optical signal of the wavelength corresponding to bit 1 passes through the band-stop filter unit with less attenuation, which is beneficial to improve the communication quality.
  • FIG. 1 is a schematic structural diagram of an optical transmission component provided by an embodiment of the present application.
  • FIG. 2 is a schematic diagram of the relationship between the wavelength of the first modulated optical signal and the forward filter spectral line of the band-stop filter unit;
  • 3 is a schematic diagram of the relationship between the wavelength of the first modulated optical signal and the filter spectral line of the bandpass filter unit;
  • FIG. 4 is a schematic structural diagram of another optical transmission component provided by an embodiment of the present application.
  • FIG. 5 is a schematic diagram of the relationship between the wavelength of the first modulated optical signal and the forward and reverse filtering spectral lines of the band-stop filter unit;
  • FIG. 6 is a schematic structural diagram of a microring resonator
  • FIG. 7 is a schematic structural diagram of another optical transmission component provided by an embodiment of the present application.
  • FIG. 8 is a schematic structural diagram of an optical transmission component provided by an embodiment of the present application.
  • FIG. 9 is a schematic structural diagram of an optical transceiver assembly provided by an embodiment of the present application.
  • FIG. 10 is a schematic diagram of networking of a passive optical network system provided by an embodiment of the present application.
  • FIG. 11 is a flowchart of a method for sending an optical signal provided by an embodiment of the present application.
  • Optical communication is a mainstream communication scheme. Due to its characteristics of ultra-high bandwidth and low electromagnetic interference, it is currently deployed on a large scale and applied to access networks represented by fiber to the home (FTTH). .
  • FTTH fiber to the home
  • PON is the main form of access network application, PON includes OLT, optical distribution network (optical distribution network, ODN) and ONU.
  • OLT and ONU are connected through ODN without any active electronic devices.
  • one OLT is connected with one ODN, and one ODN is connected with multiple ONUs.
  • Each ONU can be regarded as a user.
  • One OLT can serve multiple users through the optical transmission of ODN.
  • An optical transceiver (bi-directional Optical sub-assembly, BOSA) is configured in the OLT and the ONU.
  • Optical transceiver components mainly include optical transmitting components (transmitting optical sub-assembly, TOSA) and optical receiving components (receiving optical sub-assembly, ROSA).
  • the light-transmitting component and the light-receiving component are packaged in the housing.
  • the electrical signal is converted into an optical signal and sent through the optical sending component, and the optical signal is received and converted into an electrical signal through the optical receiving component, thereby realizing the sending and receiving of the optical signal.
  • passive optical networks that have been deployed on a large scale include gig-bit passive optical networks (GPON).
  • GPON gig-bit passive optical networks
  • the rate supported by GPON is 2.5Gbit/s or 1.25Gbit/s.
  • XGPON also called 10G-GPON
  • the rate supported by XGPON is 10Gbit/s.
  • the OLT in the GPON transmits an optical signal with a wavelength of 1490 nm and receives an optical signal with a wavelength of 1310 nm.
  • the OLT in XGPON sends optical signals with a wavelength of 1577 nm and receives optical signals with a wavelength of 1270 nm.
  • FIG. 1 is a schematic structural diagram of an optical transmission component provided by an embodiment of the present application.
  • the optical transmission assembly includes a first laser 11 and a band-stop filter unit 12 .
  • the first laser 11 is used for outputting the first modulated optical signal.
  • the information carried by the first modulated optical signal includes bit 0 and bit 1.
  • the band-stop filtering unit 12 is used for filtering the first modulated optical signal.
  • FIG. 2 is a schematic diagram showing the relationship between the wavelength of the first modulated optical signal and the forward filter spectral line of the band-stop filter unit.
  • the thin line represents the wavelength of the first modulated optical signal
  • the thick line represents the forward filtering spectral line of the band-stop filter unit.
  • the left-right direction indicates the size of the wavelength, and the wavelength gradually increases from left to right.
  • the up and down direction represents the power of the optical signal, and from bottom to top, the optical power gradually increases.
  • the wavelength corresponding to bit 0 and the wavelength corresponding to bit 1 are different.
  • the wavelength corresponding to the first peak is the wavelength corresponding to bit 1
  • the wavelength corresponding to the first peak is the peak wavelength corresponding to bit 1
  • the second peak corresponds to the wavelength corresponding to bit 1.
  • the corresponding wavelength is the wavelength corresponding to bit 0
  • the wavelength corresponding to the second peak is the peak wavelength corresponding to bit 0.
  • the peak wavelength corresponding to bit 0 is greater than the peak wavelength corresponding to bit 1.
  • the first laser 11 is a directly modulated laser (directly modulated laser, DML).
  • DML directly modulates the power supply of the laser through an electrical signal, so that the output light of the laser changes with the change of the electrical signal. Since the PON system is very cost-sensitive, and the cost of DML is relatively low, in most scenarios, the optical transmission components need to be implemented through DML.
  • the peaks of the output spectrum of DML correspond to different wavelengths, that is, adiabatic chirp. Due to the existence of dispersion in the fiber, the propagation rates of light of different wavelengths in the same fiber are different. Therefore, the adiabatic chirp of the laser will cause the inter-symbol interference between the signals after a certain distance transmission, which is a great limitation. Transmission distance. Therefore, in the embodiment of the present application, in order to suppress the adiabatic chirp of the first laser 11 , a band-stop filter unit 12 is arranged after the first laser 11 .
  • the band-stop filter unit 12 is used to lock the wavelength of the first modulated optical signal output by the first laser 11 , so that the lower limit cut-off wavelength B of the band-stop filter unit 12 is located at the corresponding bit 0 between the peak wavelength of and the peak wavelength corresponding to bit 1.
  • the band-stop filter unit 12 can filter out the optical signal of the wavelength corresponding to bit 0 in the received first modulated optical signal, obtain the second modulated optical signal, and output the second modulated optical signal.
  • the band-stop filter unit 12 locks the wavelength of the first modulated optical signal output by the first laser 11, which refers to the first center wavelength and the second wavelength in the forward filter spectral line of the band-stop filter unit 12.
  • the difference between the wavelengths of a modulated optical signal is kept within a certain difference range.
  • the band-stop filter unit locks the wavelength of the first modulated optical signal output by the first laser
  • the difference between the first center wavelength and the wavelength of the first modulated optical signal is Fixed value.
  • PRBS pseudo-random binary sequence
  • the rapid switching of bit 0 and bit 1 in the modulation information will cause thermal chirp in the laser.
  • the thermal chirp of the laser will cause the wavelength of the first modulated optical signal to change slightly around the target wavelength. For example, when the target wavelength of the first modulated optical signal is 1577 nm, and when the first modulated optical signal carries bit 1 and bit 0 , the actual wavelength of the first modulated optical signal will vary around 1577 nm. Since the band-stop filter unit has no time to respond to the slight change, the first center wavelength of the band-stop filter unit is basically unchanged, and the difference between the first center wavelength and the wavelength of the first modulated optical signal will be within a certain difference range Variety.
  • the lower limit cutoff wavelength B of the band-stop filter unit is between the peak wavelength corresponding to bit 0 and the peak wavelength corresponding to bit 1, so as to filter out the optical signal of the wavelength corresponding to bit 0 in the received first modulated optical signal.
  • the band-stop filter unit has a lower cutoff wavelength and an upper cutoff wavelength.
  • the lower cutoff wavelength and the upper cutoff wavelength are wavelengths that satisfy the following conditions: wavelengths smaller than the lower cutoff wavelength can pass through the band-stop filter unit, wavelengths greater than the upper cutoff wavelength can pass through the band-stop filter unit, and the cutoff at the upper limit The wavelength between the wavelength and the lower cutoff wavelength will be attenuated to a certain extent after passing through the filter unit.
  • the upper cutoff wavelength and the lower cutoff wavelength may be the inflection points of the amplitude change of the optical power, or the points corresponding to the amplitude change of the optical power reaching a certain degree.
  • filtering out the optical signal of the wavelength corresponding to bit 0 in the first modulated optical signal means that the first modulated optical signal of the wavelength corresponding to bit 0 will reach a certain degree of attenuation after passing through the band-stop filter unit, or even completely filtered out. In this way, the optical signal of the wavelength corresponding to bit 0 in the obtained second modulated optical signal is relatively weak, and even does not include the wavelength corresponding to bit 0 at all, thereby improving the extinction ratio (ER) of the first laser.
  • ER extinction ratio
  • the extinction ratio of a laser is an indicator to measure the quality of the modulated optical signal.
  • the extinction ratio refers to the relative ratio of the optical power of the wavelength corresponding to bit 1 to the optical power of the wavelength corresponding to bit 0 in the modulated optical signal output by the laser.
  • the extinction ratio can be calculated using the following formula.
  • ER represents the extinction ratio
  • P1 represents the optical power of the wavelength corresponding to bit 1
  • P0 represents the optical power of the wavelength corresponding to bit 0.
  • the filtering effect of the band-stop filter unit provided by the embodiment of the present application is described below by comparing the filtering spectral lines of the band-pass filter unit and the band-stop filter unit with the same bandwidth.
  • the center wavelength a of the band-pass filter and the wavelength of the first modulated optical signal output by the first laser are quite different from each other.
  • the center wavelength a of the bandpass filter unit needs to be adjusted first to lock the wavelength of the first modulated optical signal.
  • the upper limit cutoff wavelength c of the bandpass filter unit is between the peak wavelength corresponding to bit 1 and the peak wavelength corresponding to bit 0, and the lower limit cutoff wavelength of the bandpass filter unit is smaller than the peak wavelength corresponding to bit 1, for example ( b) section.
  • the optical signal of the wavelength corresponding to bit 1 has little attenuation after passing through the band-pass filtering unit, while the optical signal of the wavelength corresponding to bit 0 is attenuated greatly after passing through the band-pass filtering unit, and even cannot pass through the band-pass filtering unit.
  • the upper cutoff wavelength of the bandpass filter unit can be guaranteed to be between the peak wavelength corresponding to bit 1 and the peak wavelength corresponding to bit 0, and the lower cutoff wavelength of the bandpass filter unit can be guaranteed to be smaller than the peak wavelength corresponding to bit 1.
  • the wavelength of the modulated optical signal will be rapidly jittered due to thermal chirp, so that the peak wavelength corresponding to bit 1 will move to the corresponding band The position where the wavelength difference between the central wavelengths of the pass filter unit is greater than the threshold. In this way, the modulated optical signal of the wavelength corresponding to bit 1 will be greatly attenuated after passing through the band-pass filter unit. In the case that the modulated optical signal of the wavelength corresponding to bit 1 is attenuated too much, the communication quality is poor.
  • the band-stop filter unit As shown in part (a) of FIG. 2 , when the first laser and the band-stop filter unit start to work, the first center wavelength A of the band-stop filter unit and the output of the first laser The wavelengths of the first modulated optical signals are far apart.
  • the first center wavelength A of the band-stop filter unit needs to be adjusted first, so that the band-stop filter unit locks the wavelength of the first modulated optical signal output by the first laser.
  • the lower cutoff wavelength B of the band-stop filter unit is between the peak wavelength corresponding to bit 1 and the peak wavelength corresponding to bit 0, and the peak wavelength corresponding to bit 0 is located at the lower limit. between the cutoff wavelength B and the upper cutoff wavelength C.
  • the optical signal of the wavelength corresponding to bit 1 has very little attenuation after passing through the band-stop filter unit, while the optical signal of the wavelength corresponding to bit 0 is attenuated greatly after passing through the band-stop filter unit, and even cannot pass through the band-stop filter unit. type filter unit.
  • the embodiment of the present application can suppress the degradation of communication quality caused by the excessive attenuation of the first modulated optical signal of the wavelength corresponding to bit 1.
  • the filter unit can meet the requirements of the eye diagram mask tolerance.
  • the band-pass filter it is mainly unable to meet the requirements of the 1-level tolerance in the eye diagram template. It can be seen that the band-stop filter unit can adapt to the switching rates of various code types.
  • FIG. 4 is a schematic structural diagram of another optical transmission component provided by an embodiment of the present application.
  • the band-stop filter unit 12 includes a tunable filter 121 .
  • the tunable filter 121 has an input port, a download port, and a pass-through port.
  • the input port is used for receiving the first modulated optical signal.
  • the optical transmission assembly also includes an optical power detection unit 13 .
  • the optical power detection unit 13 is used to detect the first optical power and the second optical power.
  • the first optical power is proportional to the optical power of the first modulated optical signal received by the input port
  • the second optical power is the optical power of the optical signal of the wavelength corresponding to bit 0 output by the download port.
  • the tunable filter 121 is used for adjusting the first center wavelength of the tunable filter 121 based on the first optical power and the second optical power, so that the optical signal of the wavelength corresponding to bit 0 is output from the download port, and the second modulated optical signal is output from the download port.
  • the signal is output from the pass-through port.
  • the optical power of the optical signal output from the download port has a negative correlation with the wavelength spacing.
  • the wavelength spacing refers to the absolute value of the difference between the first center wavelength of the tunable filter and the wavelength of the optical signal received by the input port. The larger the wavelength spacing, the smaller the optical power of the optical signal output by the download port; the smaller the wavelength spacing, the greater the optical power of the optical signal output by the download port. Therefore, by adjusting the first center wavelength, the optical power of the optical signal output by the download port can be changed.
  • the ratio of the first optical power to the second optical power depends on the magnitude of the second optical power.
  • the ratio of the first optical power to the second optical power is a set value, it indicates that the first center wavelength is at a required wavelength locking position relative to the wavelength of the optical signal received by the input port. Therefore, adjusting the first center wavelength in the forward filtering spectral line based on the first optical power and the second optical power is beneficial for the tunable filtering unit to quickly lock the first modulated optical signal output by the first laser wavelength.
  • the first center wavelength of the tunable filter 121 is adjusted so that the ratio of the first optical power and the second optical power is The ratio changes until the ratio of the first optical power to the second optical power is equal to the set value, so that the difference between the first center wavelength of the tunable filter 121 and the wavelength corresponding to bit 1 remains within the aforementioned difference range.
  • the above set values can be determined by observing the eye diagram.
  • the corresponding ratio when the eye diagram mask tolerance requirements are met is used as the set value.
  • the eye diagram template includes various tolerances, such as 1-level tolerance, 0-level tolerance, rise time tolerance, fall time tolerance, etc.
  • Meeting eye mask tolerance requirements means that these kinds of tolerance requirements can be met.
  • the light outlet is used to connect the optical fiber, so that the light output from the light outlet can be transmitted through the optical fiber.
  • the optical power detection unit 13 includes: a beam splitter 131 , a first photodetector 132 and a second photodetector 131 .
  • the optical splitter 131 is located on the optical path between the first laser 11 and the tunable filter 121 .
  • the optical splitter 131 is used for dividing the first modulated optical signal into a first optical signal and a second optical signal, and transmitting the first optical signal to the input port.
  • the first optical detector 132 is used to detect the optical power of the second optical signal to obtain the first optical power.
  • the second photodetector 133 is used to detect the second optical power.
  • the optical splitting ratio of the optical splitter 131 is a set ratio, for example, the ratio of the optical power of the first optical signal and the second optical signal is 99:1 or 95:5.
  • the set ratio a small part of the first modulated optical signal can be allowed to enter the photodetector, and most of the first modulated optical signal can be output to the band-stop filter unit 12 .
  • the optical splitter By setting the optical splitter to divide the first modulated optical signal into two optical signals, the normal transmission of the first modulated optical signal can be ensured under the condition of detecting the first optical power and the second optical power.
  • the tunable filter 121 is a micro-ring resonator (MRR), a microdisk resonator, or a Mach-Zehnder interferometer.
  • MRR micro-ring resonator
  • microdisk resonator a microdisk resonator
  • Mach-Zehnder interferometer a Mach-Zehnder interferometer
  • the adjustment of the first center wavelength is exemplified below by taking a micro-ring resonator as an example.
  • the microring resonator consists of two parallel straight waveguides and a closed loop waveguide located between the two straight waveguides.
  • the resonant wavelength of the microring resonator changes.
  • the resonant wavelength of the microring resonator increases gradually.
  • the change of the effective refractive index is related to the thermo-optic coefficient and the temperature of the material of the microring resonator. Therefore, the resonant wavelength of the microring can be tuned by adjusting the temperature.
  • the first center wavelength is the resonance wavelength corresponding to the optical signal input from the input port and output from the download port.
  • a hot electrode is arranged on the ring waveguide of the microring resonator, a voltage is applied to the hot electrode, and the electrode generates Joule heat to heat the ring waveguide, so as to change the effective refractive index of the ring waveguide, thereby adjusting the resonance of the microring the resonant wavelength of the device.
  • the light transmitting component further includes a semiconductor cooler, the micro-ring resonator is arranged on the semiconductor cooler, and the temperature of the micro-ring resonator is adjusted by the semiconductor cooler, so as to adjust the temperature of the micro-ring resonator. resonance wavelength.
  • the microring resonator and the first laser are arranged on the same semiconductor cooler.
  • DML thermo-optic coefficient of DML
  • the wavelength changes of the DML and the micro-ring resonator are different. relative to the wavelength of the microring resonator.
  • the optical transmission assembly further includes an optical switch 14 .
  • the optical switch 14 is located on the optical path between the band-stop filter unit 12 and the optical outlet of the optical transmission component. The optical switch 14 is used to control whether the second modulated optical signal output by the band-stop filter unit 12 is output from the light outlet.
  • the optical line terminal usually includes an active passive optical network port and a standby passive optical network port.
  • the active passive optical network port fails to work normally (for example, the link where the active passive optical network port is located is faulty, etc.)
  • the standby passive optical network port is used to carry services. This situation is called network protection.
  • Type A type A
  • type B type B
  • type C type C
  • type B protection requires that the switching time of the active passive optical network port and the standby passive optical network port be less than 50ms.
  • the first laser in the active passive optical network port and the standby passive optical network port can be It works normally and is in a stable working state. It is only necessary to control the optical switch corresponding to one first laser to be turned on and the optical switch corresponding to the other first laser to be turned off, so that normal service bearing can be performed.
  • type B protection needs to be performed, and it is switched to the standby passive optical network port to work. Since the first laser in the standby passive optical network port is in a stable working state, the standby passive optical network port only needs to control its own optical switch. During this process, since the first laser in the standby passive optical network port will not be turned on suddenly, the thermal balance of the semiconductor refrigerator will not be destroyed, and the wavelength of the first laser will not be affected by the ambient temperature. The wavelength output by the first laser is stable, and the tunable filter can quickly complete wavelength locking. In this way, in the case of type B protection, the switching time is mainly determined by the switching time of the optical switch, and the switching time of the optical switch can generally reach the order of ⁇ m, which meets the requirement that the switching time is less than 50ms.
  • the optical switch 14 includes one input port and two output ports.
  • the input port of the optical switch 14 is used to receive the second modulated optical signal output by the band-stop filter unit 12 , and the two outputs One of the ports is used to output the second modulated optical signal to the optical outlet, and the other of the two output ports is used to output the second modulated optical signal to a position other than the optical outlet.
  • the optical switch 14 is controlled so that the second modulated optical signal is output from the optical outlet, the optical switch 14 is turned on, and when the optical switch 14 is controlled so that the second modulated optical signal is not output from the optical outlet, the optical switch 14 is turned off.
  • the optical transmission assembly further includes a third photodetector.
  • the output port for outputting the second modulated optical signal to a position other than the light outlet is coupled with the third photodetector.
  • one output port and one download port of the optical switch are coupled to the same photodetector, and the aforementioned second photodetector and third photodetector are the same photodetector.
  • the third photodetector is the second photodetector 133 .
  • the second photodetector 133 needs to monitor the download port of the tunable filter 121 and an output port of the optical switch 14 at the same time, so for the tunable filter 121
  • the control and regulation of the optical switch 14 needs to be coordinated. For example, the resonant wavelength of the micro-ring resonator 121 is adjusted first and then the optical switch 14 is adjusted, or the optical switch 14 is adjusted first and then the resonant wavelength of the micro-ring resonator 121 is adjusted.
  • the output port and the download port of the optical switch are respectively coupled to one photodetector, and the first photodetector and the third photodetector are two different photodetectors.
  • the optical switch is an optical power attenuator.
  • Optical power attenuators have one input port and one output port. The input port of the optical power attenuator is used for receiving the second modulated optical signal output by the band-stop filter unit, and the output port of the optical power attenuator is used for outputting the second modulated optical signal to the light outlet.
  • the optical switch is a mechanical optical switch, an electro-optical switch, a thermo-optical switch, a magneto-optical switch, or the like.
  • the optical switch like the first laser and tunable filter, is also provided on the semiconductor cooler. It should be noted that if the optical switch is a thermo-optic switch, then when adjusting the thermo-optic switch and the semiconductor cooler, the thermo-optic switch and the semiconductor cooler can be cross-regulated to avoid mutual interference between the thermo-optic switch and the semiconductor cooler. . Alternatively, the thermo-optic switch and the semiconductor refrigerator may be adjusted simultaneously after comprehensive consideration, which is not limited in this application.
  • the aforementioned tunable filter 121 is a reciprocal device.
  • a reciprocal device is a passive device whose input and output can be interchanged.
  • the tunable filter 121 is a non-reciprocal device.
  • a non-reciprocal device is a passive device whose input and output are not interchangeable.
  • the wavelength corresponding to the first modulated optical signal is located between the lower cutoff wavelength and the upper cutoff wavelength in the reverse filtering spectral line of the band-stop filter unit, In order to prevent the wavelength corresponding to the first modulated optical signal from passing through the band-stop filter unit 12 in the reverse direction.
  • the reverse direction refers to the direction of the optical signal from the output port of the band-stop filter unit to the input port of the band-stop filter unit.
  • FIG. 5 is a schematic diagram showing the relationship between the wavelength of the first modulated optical signal and the forward and reverse filter spectral lines of the band-stop filter unit.
  • Part (a) of FIG. 5 is a schematic diagram of the relationship between the wavelength of the first modulated optical signal and the forward filter spectral line of the band-stop filter unit
  • part (b) of FIG. 5 is the wavelength of the first modulated optical signal and the band-stop filter.
  • the second center wavelength A1 of the band-stop filter unit is located between the peak wavelength corresponding to bit 1 and the peak wavelength corresponding to bit 0, so that the band
  • the reverse lower limit cutoff wavelength B1 of the resistive filter unit is smaller than the peak wavelength corresponding to bit 1
  • the reverse upper limit cutoff wavelength C1 of the band resist filter unit is greater than the peak wavelength corresponding to bit 0.
  • the band-stop filter unit can also play the role of isolation, without using a separate isolator, so that the optical transmission component contains fewer devices and the structure is simpler.
  • non-reciprocal device The implementation of the non-reciprocal device is exemplarily described below by taking a microring resonator as an example.
  • FIG. 6 is a schematic structural diagram of a microring resonator. As shown in FIG. 6 , the microring resonator includes two parallel straight waveguides 121a and a closed loop waveguide 121b located between the two straight waveguides 121a. The magneto-optical material 121c is attached to the annular waveguide 121b.
  • the magneto-optical material includes a dilute magnetic semiconductor, a magnetic garnet, and the like.
  • Magnetic garnets include, but are not limited to, bismuth (Bi) doped yttrium iron garnet, cerium (Ce) doped yttrium iron garnet, and the like.
  • the electromagnetic field properties such as magnetization direction, magnetization intensity, dielectric constant, etc.
  • the magnetic field is formed by using a permanent magnet (eg, a magnet), which is not limited in this application.
  • the phase change is different when the optical signal passes through the micro-ring resonator in the forward direction, so that the reverse filtering of the micro-ring resonator is made.
  • the wavelengths corresponding to the filter peaks are shifted relative to the forward filtered spectral lines of the microring resonator. In this way, when the wavelength corresponding to bit 1 and the wavelength corresponding to bit 0 are input to the microring resonator from the through port, they will be output from the upload port, but not output from the input port, and thus will not enter the first laser.
  • the inverse filtering spectral line is for the filtering spectral line of the optical signal input from the through port of the tunable filter 121
  • the forward filtering spectral line is for the optical signal input from the tunable filter 121
  • the filtered spectral lines of the input optical signal at the input port is for the filtering spectral line of the optical signal input from the through port of the tunable filter 121 .
  • FIG. 7 is a schematic structural diagram of another optical transmission component provided by an embodiment of the present disclosure.
  • the optical transmission component further includes a second laser 15, and the second laser 15 is used for outputting a third modulated optical signal.
  • the wavelength of the third modulated optical signal output by the second laser 15 is different from the wavelength of the first modulated optical signal output by the first laser 11 .
  • the second laser 15 is a DML to reduce the cost of the optical transmission assembly.
  • the second laser 15 is an electroabsorption modulated laser (EML).
  • the optical sending component further includes a first wave combiner 161 .
  • the optical switch 14 is located on the optical path between the band-stop filter unit 12 and the first combiner 161 .
  • the first combiner 161 is configured to combine the second modulated optical signal output from the optical switch 14 and the third modulated optical signal output from the second laser 15 into a mixed modulated optical signal, and output the mixed modulated optical signal to the light outlet.
  • FIG. 8 is a schematic structural diagram of another optical transmission component provided by an embodiment of the present disclosure.
  • the optical transmission assembly further includes a second wave combiner 162 , and the optical switch 14 is located on the optical path between the second wave combiner 162 and the light outlet.
  • the second wave combiner 162 is used to combine the second modulated optical signal output by the band-stop filter unit 12 and the third modulated optical signal output by the second laser 15 into a mixed modulated optical signal, and transmit the mixed modulated optical signal to the optical switch 14.
  • the optical switch 14 is used to control whether the second modulated optical signal in the mixed modulated optical signal is output from the light outlet. In the embodiment shown in FIG. 8 , the optical switch switches only for the wavelength of the second modulated optical signal.
  • the third modulated optical signal can pass through the optical switch regardless of whether the optical switch is in an on state or an off state.
  • the combiner ie the first combiner 161 or the second combiner 162
  • the tunable filter 121 the optical switch 14 and the optical splitter (not shown in the figure) shown
  • the combiner are integrated on one optical chip 10 to simplify the packaging process of the optical transmission components.
  • all or some of these devices may also be discrete devices.
  • the wavelength of the second modulated optical signal when the optical transmission component includes only one laser, the wavelength of the second modulated optical signal is 1490 nm, 1310 nm, 1577 nm or 1270 nm.
  • the wavelength of the second modulated optical signal is 1577 nm, and the wavelength of the third modulated optical signal is 1490 nm.
  • the aforementioned optical transmission assembly further includes a casing, and the casing is provided with a cavity, and the casing is used to carry each optical device included in the optical transmission assembly.
  • the side wall of the casing is provided with an optical transmission interface and an optical outlet, and the number of optical transmission interfaces is the same as that of the lasers, and is used for fixing the tube casing of the corresponding laser.
  • the light outlet is used to accommodate the optical fiber.
  • the cavity is respectively communicated with the optical transmission interface and the optical fiber connection port, and is used for providing a transmission space for the optical signal.
  • FIG. 9 is a schematic structural diagram of an optical transceiver assembly provided by an embodiment of the present application.
  • the optical transceiver assembly includes an optical transmitting assembly 1 , a wavelength division multiplexing device 2 and an optical receiving assembly 3 .
  • the structure of the optical transmission module 1 in FIG. 9 is the same as that of the optical transmission module shown in FIG. 1 . It should be noted that, the optical transmission assembly 1 in FIG. 9 may adopt the optical transmission assembly shown in any of the preceding figures.
  • the wavelength division multiplexing device 2 is located between the optical transmission component 1 and the optical outlet 1a, and the wavelength division multiplexing device 2 is used to transmit the second modulated optical signal output by the optical transmission component 1 to the optical outlet 1a and to transmit the input signal from the optical outlet 1a.
  • the fourth modulated optical signal is transmitted to the light receiving component 3 .
  • the light receiving component 3 is used for receiving the fourth modulated optical signal, and converting the received fourth modulated optical signal into an electrical signal.
  • the optical signal received by the optical receiving component is also of a single wavelength.
  • the wavelength of the modulated optical signal transmitted by the optical transmitting component is 1490 nm
  • the wavelength of the optical signal received by the optical receiving component is 1310 nm.
  • the wavelength of the modulated optical signal sent by the optical transmitting component is 1577 nm
  • the wavelength of the optical signal received by the optical receiving component is 1270 nm.
  • the modulated optical signal sent by the optical transmitting component is dual wavelength
  • the optical signal received by the optical receiving component is also dual wavelength.
  • the wavelengths of the modulated optical signals transmitted by the optical transmitting component are 1490 nm and 1577 nm
  • the wavelengths of the optical signals received by the optical receiving component are 1310 nm and 1270 nm.
  • the present application also provides an optical communication device, for example, an optical module, an OLT or an ONU.
  • the optical communication device includes any one of the aforementioned optical transmission components or optical transceiver components.
  • the optical communication device is an OLT that includes the aforementioned optical transceiver components.
  • the optical communication device is an ONU, and the ONU includes the aforementioned optical transmission components.
  • the optical communication device is an optical module, including the aforementioned optical transmission components or optical transceiver components.
  • FIG. 10 is a schematic diagram of networking of a PON system provided by an embodiment of the present disclosure.
  • the PON system includes an OLT 100, an ODN 200 and at least two ONUs 300.
  • Each ONU 300 is connected to the OLT 100 through the ODN 200 respectively.
  • the ODN 200 is connected between the OLT 100 and each ONU 300, and is used to provide an optical transmission channel between the OLT 100 and each optical network unit 300.
  • the PON system sends an optical signal to the first port of the optical fiber through the OLT 100, and then transmits it to each ONU 300 from the second port of the optical fiber and the ODN 200 in turn.
  • the PON system receives the optical signals sent by each ONU 300 and transmitted by the ODN 200 through the OLT 100.
  • the PON system realizes the transmission of optical signals of at least one wavelength and the reception of optical signals of at least one wavelength.
  • At least one of the OLT 100 and the ONU 300 includes any one of the aforementioned light transmitting components or light receiving components.
  • Embodiments of the present application also provide a method for sending an optical signal, which is implemented based on the structure of the aforementioned optical sending component.
  • FIG. 11 is a flowchart of a method for sending an optical signal provided by an embodiment of the present application. As shown in Figure 11, the method includes the following processes.
  • the information carried by the first modulated optical signal includes bit 0 and bit 1, and the peak wavelength corresponding to bit 0 and the peak wavelength corresponding to bit 1 are different.
  • S2 Filter the first modulated optical signal through a band-stop filter unit.
  • the band-stop filter unit is used to lock the wavelength of the first modulated optical signal output by the first laser, so that the lower limit cut-off wavelength in the forward filter spectral line of the band-stop filter unit is at the peak wavelength corresponding to bit 0 and between the peak wavelengths corresponding to the bit 1.
  • the band-stop filter unit can filter out the optical signal of the wavelength corresponding to bit 0 in the received first modulated optical signal, obtain the second modulated optical signal, and output the second modulated optical signal.
  • the band-stop filter unit has an input port, a download port, and a pass-through port
  • S2 includes: a first step, determining a first optical power and a second optical power, the first optical power and the first optical power received by the input port
  • the optical power of the modulated optical signal is proportional
  • the second optical power is the optical power of the optical signal of the wavelength corresponding to the bit 0 output by the download port.
  • the second step is to adjust the first center wavelength based on the first optical power and the second optical power, so that the optical signal of the wavelength corresponding to bit 0 is output from the download port, and the second modulated optical signal is output from the through port.
  • the second step when the ratio of the first optical power to the second optical power is not equal to the set value, adjust the first center wavelength of the tunable filter so that the ratio of the first optical power to the second optical power changes , until the ratio of the first optical power to the second optical power is the set value. In this way, it is ensured that the difference between the first center wavelength and the wavelength of the first modulated optical signal is within a certain difference range, and the band-stop filter unit locks the wavelength of the first modulated optical signal.
  • the temperature of the first laser and the band-stop filter unit is adjusted by a semiconductor refrigerator, so as to adjust the wavelength of the first modulated optical signal output by the first laser and the forward filtering of the band-stop filter unit
  • the first center wavelength in the spectral line so that the first center wavelength follows the wavelength change of the first modulated optical signal output by the first laser, until the wavelength of the first modulated optical signal and the first center wavelength of the band-stop filter unit.
  • the difference is within the range of the difference.
  • the temperature of the band-stop filter unit is adjusted by the hot electrode in the band-stop filter unit, so that the first center wavelength changes until the wavelength of the first modulated optical signal and the band-stop filter
  • the difference of the first center wavelengths of the cells is within the range of the difference.

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Abstract

本申请实施例公开了一种光发送组件、光收发组件、光通信设备和光信号的发送方法，属于光通信领域。该光发送组件包括第一激光器和带阻型滤波单元。第一激光器用于输出第一调制光信号，第一调制光信号承载的信息包括比特0和比特1，且比特0对应的波长和比特1对应的波长不同。带阻型滤波单元用于锁定该第一调制光信号的波长，使得带阻型滤波单元的下限截止波长在所述比特0对应的峰值波长和所述比特1对应的峰值波长之间，这样，带阻型滤波单元能够将第一调制光信号中比特0对应波长的光信号滤除，得到并输出第二调制光信号。当第一调制光信号承载的信息在比特0和比特1之间快速切换时，该光发送组件能够减小比特1对应波长的光信号的衰减。

Description

光发送和光收发组件、光通信设备及光信号的发送方法
本申请要求于2021年3月29日提交中国国家知识产权局、申请号为202110333927.7、申请名称为“光发送和光收发组件、光通信设备及光信号的发送方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及光通信技术领域，特别涉及一种光发送和光收发组件、光通信设备及光信号的发送方法。
背景技术
光发送组件主要用于光信号的发送，是无源光网络(passive optical network，PON)中的重要器件。光发送组件应用于PON系统中的关键设备，例如光线路终端(optical line terminal，OLT)、光网络终端(optical network terminal，ONU)等。
光发送组件通常包括激光器和滤波单元。激光器输出的调制光信号承载的信息为由比特1和比特0组成的二进制编码序列，比特1对应的波长和比特0对应的波长不同。滤波单元通过滤除调制光信号中比特0对应的波长来提升激光器的消光比。相关技术中，该滤波单元为带通型滤波单元，且该带通型滤波单元锁定激光器输出的调制光信号的波长。
当调制光信号承载的信息在比特1和比特0之间快速切换时，调制光信号的波长会快速抖动，而带通型滤波单元的滤波谱线来不及跟踪调制光信号的波长变化，导致比特1对应波长的调制光信号衰减过大，对通信质量造成不良影响。
发明内容
本申请提供了一种光发送组件、光收发组件、光通信设备和光信号的发送方法，能够提升通信质量。
一方面，本申请提供了一种光发送组件。该光发送组件包括第一激光器和带阻型滤波单元。第一激光器用于输出第一调制光信号。第一调制光信号承载的信息包括比特0和比特1，且所述比特0对应的波长和所述比特1对应的波长不同。所述带阻型滤波单元用于锁定所述第一激光器输出的所述第一调制光信号的波长，使得所述带阻型滤波单元的正向滤波谱线中的下限截止波长在所述比特0对应的峰值波长和所述比特1对应的峰值波长之间，以将接收到的所述第一调制光信号中比特0对应波长的光信号滤除，得到第二调制光信号，以及输出所述第二调制光信号。
在本申请中，带阻型滤波单元锁定所述第一激光器输出的所述第一调制光信号的波长，是指带阻型滤波单元的正向滤波谱线中的第一中心波长与第一调制光信号的波长的差值保持在一定差值范围内。其中，正向滤波谱线是指对从带阻型滤波单元的输入端口输入的光信号 的滤波谱线。
理想状态下，当带阻型滤波单元锁定所述第一激光器输出的所述第一调制光信号的波长时，第一中心波长与第一调制光信号的波长的差值为固定值。但是实际应用中，由于第一激光器的热啁啾的存在，第一调制光信号的波长会在目标波长附近出现微小的变化。由于带阻型滤波单元来不及响应该微小变化，所以带阻型滤波单元的第一中心波长基本不变，而第一中心波长与第一调制光信号的波长的差值会在一定差值范围内变化。
带阻型滤波单元的正向滤波谱线具有下限截止波长和上限截止波长。下限截止波长和上限截止波长为满足以下条件的波长：小于该下限截止波长的波长能够通过该带阻型滤波单元，大于该上限截止波长的波长能够通过该带阻型滤波单元，而在上限截止波长和下限截止波长之间的波长经过该滤波单元后会有一定程度的衰减。
当带阻型滤波单元锁定第一调制光信号的波长时，所述带阻型滤波单元的下限截止波长位于比特0对应的峰值波长和比特1对应的峰值波长之间，比特1对应波长的调制光信号就能够在衰减较小的情况下通过该带阻型滤波单元。当第一调制光信号承载的信息在比特1和比特0之间快速切换时，第一调制光信号的光谱峰值会快速抖动。在快速抖动的过程中，比特1对应的波长始终在小于带阻型滤波单元的下限截止波长的一定范围内移动，因此，即使带阻型滤波单元来不及跟随第一调制光信号的波形的变化，比特1对应的波长仍然能够在小衰减的情况下通过带阻型滤波单元，从而提高通信质量。
在一些示例中，所述带阻型滤波单元包括可调谐滤波器。可调谐滤波器具有输入端口、下载端口和直通端口。所述光发送组件还包括光功率检测单元。光功率检测单元用于检测第一光功率和第二光功率，所述第一光功率与所述输入端口接收到的所述第一调制光信号的光功率呈正比，所述第二光功率为所述下载端口输出的所述比特0对应波长的光信号的光功率。所述可调谐滤波器用于基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长。例如，根据第一光功率和第二光功率的比值，调节第一中心波长，直至第一光功率和第二光功率的比值为设定值，此时，可调谐滤波器锁定第一调制光信号的波长。这样，第一调制光信号从输入端口输入后，比特0对应波长的光信号从所述下载端口输出，而所述第二调制光信号从所述直通端口输出。
对于可调谐滤波器而言，当输入端口接收到的光信号的波长和光功率一定时，从下载端口输出的光信号的光功率与波长间距呈负相关关系。其中，波长间距是指可调谐滤波器的第一中心波长与输入端口接收到的光信号的波长之间的差值的绝对值。波长间距越大，下载端口输出的光信号的光功率越小；波长间距越小，下载端口输出的光信号的光功率越大。因此，调节第一中心波长，能够使下载端口输出的光信号的光功率发生变化。
在第一光功率不变的情况下，第一光功率和第二光功率的比值取决于第二光功率的大小。当第一光功率和第二光功率的比值为设定值时，表示第一中心波长相对于输入端口接收到的光信号的波长处于所需要的波长锁定位置。因此，基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长，有利于可调谐滤波单元快速锁定第一激光器输出的第一调制光信号的波长。
在一些示例中，所述光功率检测单元包括：分光器、第一光探测器和第二光探测器。分光器位于所述第一激光器和所述可调谐滤波器之间的光路上，用于将所述第一调制光信号分为第一路光信号和第二路光信号，以及将所述第一路光信号传递至所述输入端口。第一光探 测器用于检测所述第二路光信号的光功率，得到所述第一光功率。第二光探测器用于检测所述第二光功率。通过设置分光器将第一调制光信号分为两路光信号，能够在检测第一光功率和第二光功率的情况下，保证第一调制光信号的正常传输。
在一些示例中，可调谐滤波器为互易性无源光器件。互易性无源光器件结构简单，产品成熟，有利于推广应用。
在另一些示例中，可调谐滤波器为非互易性无源光器件。所述带阻型滤波单元还用于调节反向滤波谱线中的第二中心波长，使得所述第一调制光信号对应的波长位于所述带阻型滤波单元的反向滤波谱线中的下限截止波长和上限截止波长之间，以阻止所述第一调制光信号对应的波长反向通过所述带阻型滤波单元。这样，该带阻型滤波单元还可以起到隔离的作用，无需采用单独的隔离器，使得光发送组件所包含的器件较少，结构更为简单。其中，反向滤波谱线是指对从带阻型滤波单元的直通端口输入的光信号的滤波谱线。
可选地，所述光发送组件还包括光开关，所述光开关位于所述带阻型滤波单元和所述光发送组件的出光口之间的光路上，所述光开关用于控制所述带阻型滤波单元输出的所述第二调制光信号是否从所述出光口输出。当光发送组件在包含于光通信设备的备用无源光网络端口时，第一激光器能够一直处于稳定工作状态。在主用无源光网络端口正常工作时，光开关关闭，备用无源光网络端口不进行业务承载。而当主用无源光网络端口无法正常工作，需要进行网络保护时，打开光开关，切换为备用无源光网络端口进行业务承载。与在进行网络保护时才启动第一激光器相比，无需等待第一激光器输出的波长稳定，可以减少切换时间。
在一些示例中，所述光开关包括一个输入端口和两个输出端口，所述光开关的输入端口用于接收所述带阻型滤波单元输出的所述第二调制光信号，所述两个输出端口中的一个用于将所述第二调制光信号输出至所述出光口，所述两个输出端口中的另一个用于将所述第二调制光信号输出至所述出光口之外的位置。
可选地，所述光发送组件还包括第三光探测器，所述两个输出端口中的另一个与所述第三光探测器耦合，与所述第三光探测器耦合的输出端口用于将第二调制光信号输出至所述第三光探测器。当第三光探测器检测到光信号时，表示光开关关闭，而当第三光探测器未检测到光信号时，表示光开关打开。
在一些示例中，光发送组件仅包括一个激光器。而在另一些示例中，光发送组件包括多个激光器。例如，除了第一激光器，光发送组件还包括第二激光器。所述第二激光器用于输出第三调制光信号。
当光发送组件包括多个激光器时，该光发送组件还包括合波器，用于将多个激光器输出的调制光信号合为混合光信号，然后从光发送组件的出光口输出。
在光发送组件包括多个激光器的情况下，光开关具有两种布置形式。一种是光开关位于带阻型滤波单元和合波器之间的光路上。合波器用于将所述光开关输出的第二调制光信号和所述第二激光器输出的第三调制光信号合为混合调制光信号，以及将所述混合调制光信号输出至所述出光口。另一种是光开关位于合波器和出光口之间的光路上。合波器用于将所述带阻型滤波单元输出的第二调制光信号和所述第二激光器输出的第三调制光信号合为混合调制光信号，以及将所述混合调制光信号传递至所述光开关，所述光开关用于控制所述混合调制光信号中的所述第二调制光信号是否从所述出光口输出。
在一些示例中，所述光发送组件还包括半导体制冷器(thermo electric cooler，TEC)， 所述第一激光器和所述带阻型滤波单元承载在所述半导体制冷器上。这样，通过半导体制冷器可以同时调节第一激光器和带阻型滤波单元的温度，使得第一激光器输出的波长和所述带阻型滤波单元的第一中心波长发生变化。由于第一激光器和带阻型滤波单元的热光系数不同，在相同的温度变化量下，第一激光器的波长变化量与第一中心波长的波长变化量不同，这样，第一激光器的波长和带阻型滤波单元的第一中心波长之间的差值发生变化，直至带阻型滤波单元锁定第一激光器输出的第一调制光信号的波长。
可选地，所述可调谐滤波器为微环谐振器、微盘谐振器或者马赫曾德干涉仪。
另一方面，本申请提供了一种光收发组件。该光收发组件包括光接收组件和光发送组件。其中，光发送组件为前述任一种光发送组件。所述波分复用器件用于将所述光发送组件输出的第二调制光信号传输至所述出光口，以及将所述出光口输入的第三调制光信号传输至所述光接收组件。所述光接收组件用于将接收到的第三调制光信号转换为电信号。
又一方面，本申请还提供了一种光通信设备。在一些示例中，该光通信设备为OLT，OLT包括前述光收发组件。在另一些示例中，该光通信设备为ONU，ONU包括前述光发送组件。在又一些示例中，光通信设备为光模块，包括前述光发送组件或者光收发组件。
又一方面，本申请还提供了一种光信号的发送方法。该方法包括：控制第一激光器输出第一调制光信号，所述第一调制光信号承载的信息包括比特0和比特1，且所述比特0对应的波长和所述比特1对应的波长不同；通过带阻型滤波单元锁定所述第一调制光信号的波长，以对所述第一调制光信号进行滤波。这里，锁定是指，所述带阻型滤波单元的正向滤波谱线中的第一中心波长与所述第一调制光信号的波长的差值保持在一定差值范围内，且使得所述带阻型滤波单元的正向滤波谱线中的下限截止波长在所述比特0对应的峰值波长和所述比特1对应的峰值波长之间。这样，所述带阻型滤波单元能够将接收到的所述第一调制光信号中比特0对应的波长的光信号滤除，得到第二调制光信号，以及输出所述第二调制光信号。
可选地，所述带阻型滤波单元包括可调谐滤波器，所述可调谐滤波器具有输入端口、下载端口和直通端口。所述通过带阻型滤波单元对所述第一调制光信号进行滤波，包括：确定第一光功率和第二光功率，所述第一光功率与所述输入端口接收到的所述第一调制光信号的光功率呈正比，所述第二光功率为所述下载端口输出的所述比特0对应波长的光信号的光功率；基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长，以使所述比特0对应波长的光信号从所述下载端口输出，以及使所述第二调制光信号从所述直通端口输出。
当所述第一激光器和所述带阻型滤波单元承载在半导体制冷器上时，所述调节所述正向滤波谱线中的第一中心波长，包括：通过所述半导体制冷器调节所述第一激光器和所述带阻型滤波单元的温度，以调节所述第一激光器输出的第一调制光信号的波长和所述第一中心波长，以使得所述第一中心波长锁定所述第一激光器输出的所述第一调制光信号的波长。
在本申请实施例中，基于所述第一光功率和所述第二光功率，调节所述可调谐滤波器的第一中心波长，包括：当第一光功率与第二光功率的比值不等于设定值时，调节所述可调谐滤波器的第一中心波长使得第一光功率与第二光功率的比值变化，直至第一光功率与第二光功率的比值等于设定值。这样，即可使得第一中心波长锁定所述第一激光器输出的所述第一调制光信号的波长。
在本申请实施例中，带阻型滤波单元锁定第一激光器输出的第一调制光信号的波长，以 对第一激光器输出的第一调制光信号进行滤波。在第一调制光信号承载的信息在比特1和比特0之间快速切换时，比特1对应的波长始终能够小于带阻型滤波单元的下限截止波长。这样，能够保证比特1对应的波长的第一调制光信号在衰减较小的情况下通过该带阻型滤波单元，有利于提升通信质量。
附图说明
图1是本申请实施例提供的一种光发送组件的结构示意图；
图2是第一调制光信号的波长与带阻型滤波单元的正向滤波谱线的关系示意图；
图3是第一调制光信号的波长与带通型滤波单元的滤波谱线的关系示意图；
图4是本申请实施例提供的另一种光发送组件的结构示意图；
图5是第一调制光信号的波长与带阻型滤波单元的正反向滤波谱线的关系示意图；
图6是一种微环谐振器的结构示意图；
图7是本申请实施例提供的又一种光发送组件的结构示意图；
图8是本申请实施例提供的一种光发送组件的结构示意图；
图9是本申请实施例提供的一种光收发组件的结构示意图；
图10是本申请实施例提供的一种无源光网络系统的组网示意图；
图11是本申请实施例提供的一种光信号的发送方法的流程图。
具体实施方式
光通信是一种主流通信方案，由于其具有超高带宽、低电磁干扰的特点，目前被大规模的部署，应用到以光纤到户(fiber to the home，FTTH)为代表的接入网中。
PON是接入网所应用的主要形式，PON包括OLT、光分布网络(optical distribution network，ODN)和ONU。OLT和ONU之间通过ODN连接，之间无任何有源电子设备。通常来说，一个OLT与一个ODN连接，而一个ODN与多个ONU连接。每个ONU都能够视作是一个用户。一个OLT能够通过ODN的光传输，服务于多个用户。
OLT和ONU中配置有光收发组件(bi-directional Optical sub-assembly，BOSA)。光收发组件主要包括光发送组件(transmitting optical sub-assembly，TOSA)和光接收组件(receiving optical sub-assembly，ROSA)。光发送组件和光接收组件封装在壳体内。通过光发送组件将电信号转化为光信号并发送，通过光接收组件将光信号接收并转化为电信号，从而实现了光信号的发送和接收。
目前来说，已经大规模部署的无源光网络包括G比特无源光网络(gig-bit passive optical network，GPON)。GPON所支持的速率为2.5Gbit/s或1.25Gbit/s。而随着网络带宽升级，下一代将要部署的无源光网络为XGPON(也可以称为10G-GPON)，XGPON所支持的速率为10Gbit/s。
示例性地，GPON中的OLT发送1490nm波长的光信号，接收1310nm波长的光信号。XGPON中的OLT发送1577nm波长的光信号，接收1270nm波长的光信号。
下面结合附图对光发送组件和光收发组件的结构进行详细说明。
图1是本申请实施例提供的一种光发送组件的结构示意图。如图1所示，该光发送组件包括第一激光器11和带阻型滤波单元12。第一激光器11用于输出第一调制光信号。第一调 制光信号承载的信息包括比特0和比特1。带阻型滤波单元12用于对第一调制光信号进行滤波。
图2是第一调制光信号的波长与带阻型滤波单元的正向滤波谱线的关系示意图。在图2中，细线表示第一调制光信号的波长，粗线表示带阻型滤波单元的正向滤波谱线。左右方向表示波长的大小，且从左到右，波长逐渐变大。上下方向表示光信号的功率大小，从下到上，光功率逐渐增大。
从图2可以看出，对于第一调制光信号，比特0对应的波长和比特1对应的波长不同。例如，图2的(a)部分和(b)部分中，第一个波峰对应的波长为比特1对应的波长，该第一个波峰对应的波长为比特1对应的峰值波长，第二个波峰对应的波长为比特0对应的波长，该第二个波峰对应的波长为比特0对应的峰值波长。比特0对应的峰值波长大于比特1对应的峰值波长。
在本申请实施例中，第一激光器11是直接调制激光器(directly modulated laser，DML)。DML是通过电信号直接调制激光器的电源，使激光器的输出光随电信号的变化而变化。由于PON系统对成本非常敏感，而DML成本较低，所以大部分场景下需要通过DML实现光发送组件。
对于DML而言，由于不同调制信息对应的注入电流或电压不同，导致DML的输出光谱的峰值对应不同的波长，即绝热啁啾。由于光纤中存在色散，不同波长的光在同一根光纤中的传播速率不同，因此，激光器的绝热啁啾会导致信号在经过一定距离的传输后，信号之间出现码间干扰，极大的限制传输距离。因此，在本申请实施例中，为了抑制第一激光器11的绝热啁啾，在第一激光器11后设置了带阻型滤波单元12。
如图2的(b)部分所示，带阻型滤波单元12用于锁定第一激光器11输出的第一调制光信号的波长，使得带阻型滤波单元12的下限截止波长B位于比特0对应的峰值波长和比特1对应的峰值波长之间。这样，带阻型滤波单元12能够将接收到的第一调制光信号中比特0对应波长的光信号滤除，得到第二调制光信号，以及输出第二调制光信号。
在本申请实施例中，带阻型滤波单元12锁定第一激光器11输出的第一调制光信号的波长，是指带阻型滤波单元12的正向滤波谱线中的第一中心波长与第一调制光信号的波长之间的差值保持在一定差值范围内。
需要说明的是，理想状态下，当带阻型滤波单元锁定所述第一激光器输出的所述第一调制光信号的波长时，第一中心波长与第一调制光信号的波长的差值为固定值。但是实际应用中，对于一些调制码型，例如伪随机二进制序列(pseudo-random binary sequence，PRBS)31码型，调制信息中的比特0和比特1的快速切换会导致激光器出现热啁啾。激光器的热啁啾会使得第一调制光信号的波长会在目标波长附近微小的变化，例如，当第一调制光信号的目标波长为1577nm，而当第一调制光信号承载比特1和比特0时，第一调制光信号的实际波长会在1577nm附近变化。由于带阻型滤波单元来不及响应该微小变化，所以带阻型滤波单元的第一中心波长基本不变，而第一中心波长与第一调制光信号的波长的差值会在一定差值范围内变化。
由于带阻型滤波单元12的带宽固定，当第一中心波长与第一调制光信号的波长之间的差值保持在该差值范围内时，使得带阻型滤波单元的下限截止波长B在比特0对应的峰值波长和比特1对应的峰值波长之间，以将接收到的第一调制光信号中比特0对应波长的光信号滤 除。
在本申请实施例中，带阻型滤波单元具有下限截止波长和上限截止波长。下限截止波长和上限截止波长为满足以下条件的波长：小于该下限截止波长的波长能够通过该带阻型滤波单元，大于该上限截止波长的波长能够通过该带阻率滤波单元，而在上限截止波长和下限截止波长之间的波长经过该滤波单元后会有一定程度的衰减。
在本申请实施例中，上限截止波长和下限截止波长可以为光功率的幅度变化的拐点，或者，光功率幅度变化达到一定程度所对应的点。
在一些示例中，将第一调制光信号中比特0对应波长的光信号滤除，是指比特0对应波长的第一调制光信号经过该带阻型滤波单元后会达到一定的衰减程度，甚至完全被滤除。这样，得到的第二调制光信号中比特0对应波长的光信号较弱，甚至完全不包括比特0对应波长，从而提高第一激光器的消光比(extinction ratio，ER)。
激光器的消光比是衡量调制光信号的质量的一个指标。消光比是指激光器输出的调制光信号中比特1对应波长的光功率和比特0对应波长的光功率的相对比值。消光比可以采用以下公式计算。
ER＝P1/P0   (1)
ER＝10log 10(P1/P0)   (2)
公式(1)和公式(2)中，ER表示消光比，P1表示比特1对应波长的光功率，P0表示比特0对应波长的光功率。
从公式(1)和公式(2)可以看出，P0越小，ER越大，激光器输出的光信号的质量越好。因此，滤除第一调制光信号中比特0对应的波长，能够实现消光比的提升。
下面以带宽相同的带通型滤波单元和带阻型滤波单元的滤波谱线进行对比，对本申请实施例提供的带阻型滤波单元的滤波效果进行说明。
如图3的(a)部分所示，在第一激光器和带通型滤波单元刚开始工作时，带通型滤波器的中心波长a和第一激光器输出的第一调制光信号的波长相差较远。需要先调整带通型滤波单元的中心波长a，以锁定第一调制光信号的波长。这样，带通型滤波单元的上限截止波长c在比特1对应的峰值波长和比特0对应的峰值波长之间，带通滤波单元的下限截止波长小于比特1对应的峰值波长，例如图3的(b)部分所示。比特1对应的波长的光信号通过该带通型滤波单元后的衰减很小，而比特0对应的波长的光信号通过该带通滤波单元后衰减较大，甚至无法通过该带通滤波单元。
如图3的(b)部分所示，由于带通型滤波单元的带宽较窄，只有当带通型滤波单元的中心波长与比特1对应的峰值波长之间的波长差小于阈值时，例如基本重合时，才能够保证带通型滤波单元的上限截止波长在比特1对应的峰值波长和比特0对应的峰值波长之间，且保证带通滤波单元的下限截止波长小于比特1对应的峰值波长。
当激光器输出的调制光信号承载的信息在比特1和比特0之间快速切换时，调制光信号的波长会因为热啁啾而发生快速抖动，使得比特1对应的峰值波长会移动到与该带通型滤波单元的中心波长之间的波长差大于该阈值的位置。这样，比特1对应波长的调制光信号通过该带通型滤波单元后会产生较大的衰减。在比特1对应波长的调制光信号衰减过大的情况下，导致通信质量较差。
而对于带阻型滤波单元，如图2的(a)部分所示，在第一激光器和带阻型滤波单元刚开 始工作时，带阻型滤波单元的第一中心波长A和第一激光器输出的第一调制光信号的波长相差较远。需要先调整带阻型滤波单元的第一中心波长A，使得带阻型滤波单元锁定第一激光器输出的第一调制光信号的波长。锁定后，如图2的(b)部分所示，带阻型滤波单元的下限截止波长B在比特1对应的峰值波长和比特0对应的峰值波长之间，且比特0对应的峰值波长位于下限截止波长B和上限截止波长C之间。这样，比特1对应的波长的光信号通过该带阻型滤波单元后的衰减很小，而比特0对应的波长的光信号通过该带阻型滤波单元后衰减较大，甚至无法通过该带阻型滤波单元。
在第一调制光信号承载的信息在比特1和比特0之间快速切换的情况下，由于带阻型滤波单元的通带部分较宽，即使比特1对应的波长因为热啁啾而发生红移(即向图2的(b)部分的右边移动)且第一中心波长基本不动，比特1对应的波长的第一调制光信号仍然能在基本无衰减的情况下通过该带阻型滤波单元。所以本申请实施例能够抑制由于比特1对应的波长的第一调制光信号的衰减过大而导致的通信质量下降。
需要说明的是，图2的(b)部分中，比特1对应的波长和下截止波长B之间的距离接近，但由于热啁啾引起的波长移动距离很小，所以比特1对应的波长右移后仍然位于下截止波长B的左边。
通过示波器观察两种光发送组件以伪随机二进制序列(pseudo-random binary sequence，PRBS)码型发送第一调制光信号时对应的眼图，眼图模板容限均正常。而通过示波器观察两种光发送组件以PRBS31码型发送第一调制光信号时对应的眼图，采用带通型滤波单元的光发送组件不能满足眼图模板容限的要求，而采用带阻型滤波单元能够满足眼图模板容限的要求。这里，对于采用带通型滤波器的光发送组件，主要是不能满足眼图模板中1电平容限的要求。可见，带阻型滤波单元能够适应各种码型的切换速率。
图4为本申请实施例提供的另一种光发送组件的结构示意图。如图4所示，带阻型滤波单元12包括可调谐滤波器121。该可调谐滤波器121具有输入端口、下载端口和直通端口。输入端口用于接收第一调制光信号。该光发送组件还包括光功率检测单元13。光功率检测单元13用于检测第一光功率和第二光功率。第一光功率与输入端口接收到的第一调制光信号的光功率呈正比，第二光功率为下载端口输出的比特0对应波长的光信号的光功率。可调谐滤波器121用于基于第一光功率和第二光功率，调节可调谐滤波器121的第一中心波长，以使比特0对应波长的光信号从下载端口输出，以及使第二调制光信号从直通端口输出。
对于可调谐滤波器而言，当输入端口接收到的光信号的波长和光功率一定时，从下载端口输出的光信号的光功率与波长间距呈负相关关系。其中，波长间距是指可调谐滤波器的第一中心波长与输入端口接收到的光信号的波长之间的差值的绝对值。波长间距越大，下载端口输出的光信号的光功率越小；波长间距越小，下载端口输出的光信号的光功率越大。因此，调节第一中心波长，能够使下载端口输出的光信号的光功率发生变化。
在第一光功率不变的情况下，第一光功率和第二光功率的比值取决于第二光功率的大小。当第一光功率和第二光功率的比值为设定值时，表示第一中心波长相对于输入端口接收到的光信号的波长处于所需要的波长锁定位置。因此，基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长，有利于可调谐滤波单元快速锁定第一激光器输出的第一调制光信号的波长。
在本申请实施例中，当第一光功率和第二光功率的比值不等于设定值时，通过调节可调 谐滤波器121的第一中心波长，使得第一光功率和第二光功率的比值变化，直至第一光功率和第二光功率的比值等于设定值，进而使得可调谐滤波器121的第一中心波长与比特1对应的波长的差值保持在前述差值范围内。
上述设定值可以通过观察眼图来确定。在满足眼图模板容限要求时所对应的比值作为该设定值。眼图模板中包括多种容限，例如，1电平容限，0电平容限、上升时间容限、下降时间容限等。满足眼图模板容限要求是指这些种类的容限要求均能被满足。
在本申请实施例中，出光口用于连接光纤，使得从出光口输出的光能够通过光纤传输。
在一些示例中，光功率检测单元13包括：分光器131、第一光探测器132和第二光探测器131。分光器131位于第一激光器11和可调谐滤波器121之间的光路上。分光器131用于将第一调制光信号分为第一路光信号和第二路光信号，以及将第一路光信号传递至输入端口。第一光探测器132用于检测第二路光信号的光功率，得到第一光功率。第二光探测器133用于检测第二光功率。
在本申请实施例中，分光器131的分光比为设定比例，例如第一路光信号和第二路光信号的光功率的比值为99：1或者95:5。通过该设定比例，能够让第一调制光信号的少部分进入光探测器，第一调制光信号的大部分输出至带阻型滤波单元12。
通过设置分光器将第一调制光信号分为两路光信号，能够在检测第一光功率和第二光功率的情况下，保证第一调制光信号的正常传输。
在一些示例中，可调谐滤波器121为微环谐振器(micro-ring resonator，MRR)、微盘谐振器或者马赫曾德干涉仪。
下面以微环谐振器为例对第一中心波长的调节进行示例性说明。微环谐振器包括平行的两根直波导和位于两根直波导之间的闭合环形波导。
当环形波导的有效折射率发生变化时，会使得微环谐振器的谐振波长产生变化。随着有效折射率的增加，微环谐振器的谐振波长会逐渐增大。而有效折射率的变化与微环谐振器的材料的热光系数以及温度的大小有关。因此，可以通过调节温度来调节微环的谐振波长。在本申请实施例中，第一中心波长为光信号从输入端口输入，且从下载端口输出时所对应的谐振波长。
在一种可能的实施方式中，在微环谐振器的环形波导上设置热电极，向热电极施加电压，电极产生焦耳热加热环形波导，以改变环形波导的有效折射率，从而调节微环谐振器的谐振波长。
在另一种可能的实施方式中，光发送组件还包括半导体制冷器，微环谐振器设置在半导体制冷器上，通过半导体制冷器来调节微环谐振器的温度，从而调节微环谐振器的谐振波长。
示例性地，微环谐振器和第一激光器设置在同一个半导体制冷器上。当第一激光器采用DML时，由于DML的热光系数大于微环谐振器的热光系数，因此，半导体制冷器进行温度调节时，DML和微环谐振器的波长变化量不同，从而可以对DML和微环谐振器的波长进行相对调节。
在一些示例中，如图4所示，该光发送组件还包括光开关14。光开关14位于带阻型滤波单元12和光发送组件的出光口之间的光路上。光开关14用于控制带阻型滤波单元12输出的第二调制光信号是否从出光口输出。
为了保证业务的不中断，光线路终端通常包括主用无源光网络端口和备用无源光网络端口。在主用无源光网络端口无法正常工作(例如主用无源光网络端口所在的链路发生故障等)时，由备用无源光网络端口进行业务承载。这种情况被称为网络保护。
相关标准中，网络保护分为类型A(type A)、类型B(type B)和类型C(type C)保护。其中，type B保护较为常用。Type B保护要求主用无源光网络端口和备用无源光网络端口的切换时间要小于50ms。
当主用无源光网络端口和备用无源光网络端口中的光发送组件均采用图3所示结构时，主用无源光网络端口和备用无源光网络端口中的第一激光器，均可以正常工作，处于稳定工作状态。只需要控制一个第一激光器对应的光开关打开，另一个第一激光器对应的光开关关闭，就能进行正常的业务承载。
假设主用无源光网络端口故障，需要进行type B保护，切换到备用无源光网络端口工作。由于备用无源光网络端口中的第一激光器处于稳定工作状态，所以备用无源光网络端口只需要对自己的光开关进行控制即可。在该过程中，由于备用无源光网络端口中的第一激光器不会突然被打开，所以不会破坏半导体制冷器的热平衡，第一激光器的波长也不会受到环境温度的影响。第一激光器输出的波长稳定，可调谐滤波器能够快速完成波长锁定。这样，在type B保护的情况下，切换时间主要由光开关的切换时间决定，而光开关的切换时间一般可以达到μm量级，满足切换时间小于50ms的要求。
在一些示例中，如图4所示，光开关14包括一个输入端口和两个输出端口，光开关14的输入端口用于接收带阻型滤波单元12输出的第二调制光信号，两个输出端口中的一个用于将第二调制光信号输出至出光口，两个输出端口中的另一个用于将第二调制光信号输出至出光口之外的位置。当控制光开关14使得第二调制光信号从与出光口输出时，表示光开关14打开，而控制光开关14使得第二调制光信号不从出光口输出时，表示光开关14关闭。
在光开关包括一个输入端口和两个输出端口的情况下，光发送组件还包括第三光探测器。用于将第二调制光信号输出至出光口之外的位置的输出端口与第三光探测器耦合。当第三光探测器检测到光信号且对应的电流最大时，表示光开关关闭，而当第三光探测器未检测到光信号时，表示光开关打开。
在一些示例中，光开光的一个输出端口和下载端口与同一光探测器耦合，前述第二光探测器和第三光探测器为同一个光探测器。例如图4中，第三光探测器即为第二光探测器133。当光开光的一个输出端口和下载端口与同一光探测器耦合时，第二光探测器133需要同时监控可调谐滤波器121的下载端口和光开关14的一个输出端口，所以对可调谐滤波器121和光开关14的控制和调节需要协调进行。例如，先调节微环谐振器121的谐振波长再调节光开关14，或者，先调节光开关14再调节微环谐振器121的谐振波长。
需要说明的是，在其他实施例中，光开光的输出端口和下载端口分别与一个光探测器耦合，第一光探测器和第三光探测器为两个不同的光探测器。
在另一些示例中，光开关为光功率衰减器。光功率衰减器具有一个输入端口和一个输出端口。光功率衰减器的输入端口用于接收带阻型滤波单元输出的第二调制光信号，光功率衰减器的输出端口用于将第二调制光信号输出至出光口。
在本申请实施例中，光开关为机械式光开关、电光开关、热光开关、磁光开关等。
在一些示例中，光开关与第一激光器和可调谐滤波器一样，也设置在半导体制冷器上。 需要说明的是，如果光开关为热光开关，那么在调节热光开关和半导体制冷器时，可以交叉调节热光开关和半导体制冷器，以避免热光开关和半导体制冷器之间的相互干扰。或者，可以综合考虑后同时调节热光开关和半导体制冷器，本申请对此不做限制。
在一些示例中，前述可调谐滤波器121为互易性器件。互易性器件是指输入端和输出端能够互换的无源器件。在另一些示例中，可调谐滤波器121为非互易性器件。非互易性器件是指输入端和输出端不能够互换的无源器件。
当可调谐滤波器121为非互易性器件时，所述第一调制光信号对应的波长位于所述带阻型滤波单元的反向滤波谱线中的下限截止波长和上限截止波长之间，以阻止第一调制光信号对应的波长反向通过带阻型滤波单元12。这里，反向是指光信号从带阻型滤波单元的输出端口到从带阻型滤波单元的输入端口的方向。
图5是第一调制光信号的波长与带阻型滤波单元的正反向滤波谱线的关系示意图。图5的(a)部分是第一调制光信号的波长与带阻型滤波单元的正向滤波谱线的关系示意图，图5的(b)部分是第一调制光信号的波长与带阻型滤波单元的反向滤波谱线的关系示意图。从图5可以看出，带阻型滤波单元的正反向滤波谱线的波形相同，通过将正向滤波谱线平移能够得到该反向滤波谱线。
如图5的(b)部分所示，在该反向滤波谱线中，带阻型滤波单元的第二中心波长A1位于比特1对应的峰值波长和比特0对应的峰值波长之间，使得带阻型滤波单元的反向下限截止波长B1小于比特1对应的峰值波长，而带阻型滤波单元的反向上限截止波长C1大于比特0对应的峰值波长。这样，比特1对应的波长和比特0对应的波长均不能反向通过该带阻型滤波单元，从而避免对第一激光器产生不良影响。这样，该带阻型滤波单元还可以起到隔离的作用，无需采用单独的隔离器，使得光发送组件所包含的器件较少，结构更为简单。
下面以微环谐振器为例，对非互易性器件的实现方式进行示例性说明。
图6是是一种微环谐振器的结构示意图。如图6所示，该微环谐振器包括平行的两根直波导121a和位于两根直波导121a之间的闭合环形波导121b。其中，环形波导121b上附着有磁光材料121c。
在本申请实施例中，磁光材料包括稀磁半导体、磁性石榴石等。磁性石榴石包括但不限于掺铋(Bi)的钇铁石榴石和掺铈(Ce)的钇铁石榴石等。在外界磁场(例如图6中的箭头所示)作用下，磁光材料的电磁场属性(例如磁化方向、磁化强度、介电常数等)会发生改变，从而影响在该磁光材料中传输的光的特性。这里，磁场采用永磁体(例如磁铁)形成，本申请对此不做限制。
通过磁光效应，使得光信号反向经过该微环谐振器时，相对于光信号正向经过该微环谐振器，经过环形波导时相位变化不同，从而使得该微环谐振器的反向滤波谱线相对于微环谐振器的正向滤波谱线，滤波峰对应的波长有所偏移。这样，当比特1对应的波长和比特0对应的波长从直通端口输入微环谐振器时，会从上载端口输出，而不会从输入端口输出，从而不会进入第一激光器。
需要说明的是，在本申请实施例中，反向滤波谱线是针对从可调谐滤波器121的直通端口输入的光信号的滤波谱线，正向滤波谱线是针对从可调谐滤波器121的输入端口输入的光信号的滤波谱线。
图7是本公开实施例提供的另一种光发送组件的结构示意图。如图7所示，该光发送组件还包括第二激光器15，第二激光器15用于输出第三调制光信号。该第二激光器15输出的第三调制光信号的波长与第一激光器11输出的第一调制光信号的波长不同。
可选地，第二激光器15为DML，以降低光发送组件的成本。或者，第二激光器15为电吸收调制激光器(electroabsorption modulated laser，EML)。
为了将第二调制光信号和第二激光器15输出的第三调制光信号同时从出光口输出，该光发送组件还包括第一合波器161。光开关14位于带阻型滤波单元12和第一合波器161之间的光路上。第一合波器161用于将光开关14输出的第二调制光信号和第二激光器15输出的第三调制光信号合为混合调制光信号，以及将混合调制光信号输出至出光口。
图8是本公开实施例提供的另一种光发送组件的结构示意图。与图7所示的区别在于，该光发送组件还包括第二合波器162，光开关14位于第二合波器162与出光口之间的光路上。第二合波器162用于将带阻型滤波单元12输出的第二调制光信号和第二激光器15输出的第三调制光信号合为混合调制光信号，以及将混合调制光信号传递至光开关14。光开关14用于控制混合调制光信号中的第二调制光信号是否从出光口输出。在图8所示实施例中，光开关只针对第二调制光信号的波长进行开关。无论光开关处于打开状态还是关闭状态，第三调制光信号均能够通过该光开关。
在图7和图8所示的光发送组件中，合波器(即第一合波器161或第二合波器162)、可调谐滤波器121、光开关14以及分光器(图中未示出)均集成在一个光芯片10上，以简化光发送组件的封装流程。在其他实施例中，这些器件中的全部或者部分也可以为分立的器件。
在本申请实施例中，当光发送组件仅包括一个激光器时，第二调制光信号的波长为1490nm、1310nm、1577nm或者1270nm。当光发送组件包括第一激光器和第二激光器时，第二调制光信号的波长为1577nm，第三调制光信号的波长为1490nm。
此外，前述光发送组件还包括壳体，壳体内具有腔体，壳体用于承载光发送组件所包含的各个光器件。壳体的侧壁具有光发送接口和出光口，光发送接口的数量与激光器的数量相同，用于固定对应的激光器的管壳。出光口用于容置光纤。腔体分别与光发送接口和光纤连接口连通，用于为光信号提供传输的空间。
本申请实施例还提供了一种光收发组件。图9是本申请实施例提供的一种光收发组件的结构示意图。如图9所示，该光收发组件包括光发送组件1、波分复用器件2和光接收组件3。图9中的光发送组件1的结构与图1所示的光发送组件的结构相同。需要说明的是，图9中的光发送组件1可以采用前述任一幅图所示的光发送组件。波分复用器件2位于光发送组件1和出光口1a之间，波分复用器件2用于将光发送组件1输出的第二调制光信号传输至出光口1a以及将出光口1a输入的第四调制光信号传输至光接收组件3。光接收组件3用于接收第四调制光信号，以及将接收到的第四调制光信号转换为电信号。
当光发送组件发送的调制光信号为单波长时，光接收组件接收的光信号也是单波长的。例如，光发送组件发送的调制光信号的波长为1490nm，光接收组件接收的光信号的波长为1310nm。又例如，光发送组件发送的调制光信号的波长为1577nm，光接收组件接收的光信号的波长为1270nm。而当光发送组件发送的调制光信号是双波长时，光接收组件接收的光信号也是双波长的。例如，光发送组件发送的调制光信号的波长为1490nm和1577nm，光接收组 件接收的光信号的波长为1310nm和1270nm。
本申请还提供了一种光通信设备，例如，光模块、OLT或者ONU。该光通信设备包括前述任一种光发送组件或者光收发组件。在一些示例中，该光通信设备为OLT，OLT包括前述光收发组件。在另一些示例中，该光通信设备为ONU，ONU包括前述光发送组件。在又一些示例中，光通信设备为光模块，包括前述光发送组件或者光收发组件。
图10是本公开实施例提供的一种PON系统的组网示意图。如图10所示，该PON系统包括OLT 100、ODN 200和至少两个ONU 300。各ONU 300分别通过ODN 200与OLT 100连接。
ODN 200连接在OLT 100和各ONU 300之间，用于为OLT 100和各光网络单元300之间提供光传输通道。PON系统通过OLT 100发送光信号至光纤的第一端口，再依次由光纤的第二端口、ODN 200传输至各ONU 300。PON系统通过OLT 100接收由各ONU 300发送，并由ODN 200传输的光信号。该PON系统实现了至少一个波长的光信号的发送和至少一个波长的光信号的接收。
OLT 100和ONU 300中的至少一个包括前述任一种光发送组件或者光接收组件。
本申请实施例还提供了一种光信号的发送方法，基于前述光发送组件的结构实现。图11是本申请实施例提供的一种光信号的发送方法的流程图。如图11所示，该方法包括以下过程。
S1，控制第一激光器输出第一调制光信号。
其中，第一调制光信号承载的信息包括比特0和比特1，且比特0对应的峰值波长和比特1对应的峰值波长不同。
S2，通过带阻型滤波单元对第一调制光信号进行滤波。
在S2中，带阻型滤波单元用于锁定第一激光器输出的第一调制光信号的波长，使得带阻型滤波单元的正向滤波谱线中的下限截止波长在比特0对应的峰值波长和所述比特1对应的峰值波长之间。这样，带阻型滤波单元能够将接收到的第一调制光信号中比特0对应波长的光信号滤除，得到第二调制光信号，以及输出第二调制光信号。
在一些示例中，带阻型滤波单元具有输入端口、下载端口和直通端口，S2包括：第一步，确定第一光功率和第二光功率，第一光功率与输入端口接收到的第一调制光信号的光功率呈正比，第二光功率为下载端口输出的比特0对应波长的光信号的光功率。第二步，基于第一光功率和第二光功率，调节第一中心波长，以使比特0对应波长的光信号从下载端口输出，以及使第二调制光信号从直通端口输出。在第二步中，当第一光功率与第二光功率的比值不等于设定值时，调节所述可调谐滤波器的第一中心波长使得第一光功率与第二光功率的比值变化，直至第一光功率和第二光功率的比值为设定值。这样，保证第一中心波长与第一调制光信号的波长的差值在一定差值范围内，完成带阻型滤波单元对第一调制光信号的波长的锁定。
在一种可能的实施方式中，通过半导体制冷器调节第一激光器和带阻型滤波单元的温度，以调节第一激光器输出的第一调制光信号的波长和带阻型滤波单元的正向滤波谱线中的第一中心波长，以使得第一中心波长跟随第一激光器输出的第一调制光信号的波长变化，直至第一调制光信号的波长和带阻型滤波单元的第一中心波长的差值在该差值范围内。
在另一种可能的实施方式中，通过带阻型滤波单元中的热电极，调节带阻型滤波单元的温度，使得第一中心波长变化，直至第一调制光信号的波长和带阻型滤波单元的第一中心波 长的差值在该差值范围内。
光信号的发送方法的详细内容可参见前述光发送组件的相关实施例，在此省略详细描述。
除非另作定义，此处使用的技术术语或者科学术语应当为本公开所属领域内具有一般技能的人士所理解的通常意义。本公开专利申请说明书以及权利要求书中使用的“第一”、“第二”、“第三”以及类似的词语并不表示任何顺序、数量或者重要性，而只是用来区分不同的组成部分。同样，“一个”或者“一”等类似词语也不表示数量限制，而是表示存在至少一个。“包括”或者“包含”等类似的词语意指出现在“包括”或者“包含”前面的元件或者物件涵盖出现在“包括”或者“包含”后面列举的元件或者物件及其等同，并不排除其他元件或者物件。“耦合”等类似的词语是指A与B之间通过物理连接或者空间对准的方式在A和B之间形成光路。
以上所述仅为本申请一个实施例，并不用以限制本申请，凡在本申请的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。

Claims (15)

  1. 一种光发送组件，其特征在于，包括：
    第一激光器，用于输出第一调制光信号，所述第一调制光信号承载的信息包括比特0和比特1，且所述比特0对应的波长和所述比特1对应的波长不同；
    带阻型滤波单元，所述带阻型滤波单元用于锁定所述第一激光器输出的所述第一调制光信号的波长，使得所述带阻型滤波单元的正向滤波谱线中的下限截止波长在所述比特0对应的峰值波长和所述比特1对应的峰值波长之间，以将接收到的所述第一调制光信号中滤除比特0对应波长的光信号，得到第二调制光信号，以及输出所述第二调制光信号。
  2. 根据权利要求1所述的光发送组件，其特征在于，所述带阻型滤波单元包括：可调谐滤波器，具有输入端口、下载端口和直通端口；
    所述光发送组件还包括：光功率检测单元，用于检测第一光功率和第二光功率，所述第一光功率与所述输入端口接收到的所述第一调制光信号的光功率呈正比，所述第二光功率为所述下载端口输出的所述比特0对应波长的光信号的光功率；
    所述可调谐滤波器用于基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长，以使所述比特0对应波长的光信号从所述下载端口输出，以及使所述第二调制光信号从所述直通端口输出。
  3. 根据权利要求2所述的光发送组件，其特征在于，所述光功率检测单元包括：
    分光器，位于所述第一激光器和所述可调谐滤波器之间的光路上，用于将所述第一调制光信号分为第一路光信号和第二路光信号，以及将所述第一路光信号传递至所述输入端口；
    第一光探测器，用于检测所述第二路光信号的光功率，得到所述第一光功率；
    第二光探测器，用于检测所述第二光功率。
  4. 根据权利要求1至3任一项所述的光发送组件，其特征在于，所述带阻型滤波单元还用于调节反向滤波谱线中的第二中心波长，使得所述第一调制光信号对应的波长位于所述带阻型滤波单元的反向滤波谱线中的下限截止波长和上限截止波长之间。
  5. 根据权利要求1至4任一项所述的光发送组件，其特征在于，所述光发送组件还包括光开关，所述光开关位于所述带阻型滤波单元和所述光发送组件的出光口之间的光路上，所述光开关用于控制所述带阻型滤波单元输出的所述第二调制光信号是否从所述出光口输出。
  6. 根据权利要求5所述的光发送组件，其特征在于，所述光发送组件还包括第三光探测器，所述光开关包括一个输入端口和两个输出端口，所述光开关的输入端口用于接收所述带阻型滤波单元输出的所述第二调制光信号，所述两个输出端口中的一个用于将所述第二调制光信号输出至所述出光口，所述两个输出端口中的另一个用于将所述第二调制光信号输出至所述第三光探测器。
  7. 根据权利要求5或6所述的光发送组件，其特征在于，所述光发送组件还包括：
    第二激光器，用于输出第三调制光信号；
    第一合波器，用于将所述光开关输出的所述第二调制光信号和所述第二激光器输出的第三调制光信号合为混合调制光信号，以及将所述混合调制光信号输出至所述出光口。
  8. 根据权利要求5或6所述的光发送组件，其特征在于，所述光发送组件还包括：
    第二激光器，用于输出第三调制光信号；
    第二合波器，用于将所述带阻型滤波单元输出的所述第二调制光信号和所述第二激光器输出的第三调制光信号合为混合调制光信号，以及将所述混合调制光信号传递至所述光开关，所述光开关用于控制所述混合调制光信号中的所述第二调制光信号是否从所述出光口输出。
  9. 根据权利要求1至8任一项所述的光发送组件，其特征在于，所述光发送组件还包括半导体制冷器，所述第一激光器和所述带阻型滤波单元承载在所述半导体制冷器上。
  10. 根据权利要求2或3所述的光发送组件，其特征在于，所述可调谐滤波器为微环谐振器、微盘谐振器或者马赫曾德干涉仪。
  11. 一种光收发组件，其特征在于，包括光接收组件、波分复用器件和如权利要求1至10任一项所述的光发送组件，所述波分复用器件用于将所述光发送组件输出的第二调制光信号传输至出光口，以及将所述出光口输入的第四调制光信号传输至所述光接收组件。
  12. 一种光通信设备，其特征在于，包括如权利要求1至10任一项所述的光发送组件，或者包括如权利要求11所述的光收发组件。
  13. 一种光信号的发送方法，其特征在于，包括：
    控制第一激光器输出第一调制光信号，所述第一调制光信号承载的信息包括比特0和比特1，且所述比特0对应的波长和所述比特1对应的波长不同；
    通过带阻型滤波单元对所述第一调制光信号进行滤波，所述带阻型滤波单元用于锁定所述第一激光器输出的所述第一调制光信号的波长，使得所述带阻型滤波单元的正向滤波谱线中的下限截止波长在所述比特0对应的峰值波长和所述比特1对应的峰值波长之间，以将接收到的所述第一调制光信号中比特0对应波长的光信号滤除，得到第二调制光信号，以及输出所述第二调制光信号。
  14. 根据权利要求13所述的方法，其特征在于，所述带阻型滤波单元包括可调谐滤波器，所述可调谐滤波器具有输入端口、下载端口和直通端口，
    所述通过带阻型滤波单元对所述第一调制光信号进行滤波，包括：
    确定第一光功率和第二光功率，所述第一光功率与所述输入端口接收到的所述第一调制光信号的光功率呈正比，所述第二光功率为所述下载端口输出的所述比特0对应波长的光信号的光功率；
    基于所述第一光功率和所述第二光功率，调节所述正向滤波谱线中的第一中心波长，以使所述比特0对应波长的光信号从所述下载端口输出，以及使所述第二调制光信号从所述直通端口输出。
  15. 根据权利要求14所述的方法，其特征在于，所述第一激光器和所述带阻型滤波单元承载在半导体制冷器上，所述调节所述正向滤波谱线中的第一中心波长，包括：
    通过所述半导体制冷器调节所述第一激光器和所述带阻型滤波单元的温度，以调节所述第一激光器输出的所述第一调制光信号的波长和所述第一中心波长，以使得所述第一中心波长跟随所述第一激光器输出的所述第一调制光信号的波长变化。
PCT/CN2022/079749 2021-03-29 2022-03-08 光发送和光收发组件、光通信设备及光信号的发送方法 WO2022206310A1 (zh)

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Citations (5)

* Cited by examiner, † Cited by third party
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JP2004104562A (ja) * 2002-09-11 2004-04-02 Toshiba Corp 光送信器およびこれを用いた波長多重光通信システム
US20040131367A1 (en) * 2003-01-02 2004-07-08 Sung-Kee Kim EML transmitter applying band stop filter
US20090003843A1 (en) * 2007-06-19 2009-01-01 Hirotaka Oomori Optical transmitter and method for control the same
CN105450309A (zh) * 2015-11-11 2016-03-30 烽火通信科技股份有限公司 基于单个光滤波器的高速信号频率均衡和啁啾管理方法
CN112262534A (zh) * 2018-09-24 2021-01-22 华为技术有限公司 光通信系统

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004104562A (ja) * 2002-09-11 2004-04-02 Toshiba Corp 光送信器およびこれを用いた波長多重光通信システム
US20040131367A1 (en) * 2003-01-02 2004-07-08 Sung-Kee Kim EML transmitter applying band stop filter
US20090003843A1 (en) * 2007-06-19 2009-01-01 Hirotaka Oomori Optical transmitter and method for control the same
CN105450309A (zh) * 2015-11-11 2016-03-30 烽火通信科技股份有限公司 基于单个光滤波器的高速信号频率均衡和啁啾管理方法
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