WO2017045360A1 - Optical network unit of passive optical network and optical module thereof - Google Patents

Optical network unit of passive optical network and optical module thereof Download PDF

Info

Publication number
WO2017045360A1
WO2017045360A1 PCT/CN2016/074049 CN2016074049W WO2017045360A1 WO 2017045360 A1 WO2017045360 A1 WO 2017045360A1 CN 2016074049 W CN2016074049 W CN 2016074049W WO 2017045360 A1 WO2017045360 A1 WO 2017045360A1
Authority
WO
WIPO (PCT)
Prior art keywords
laser
driving circuit
pass filter
optical module
optical
Prior art date
Application number
PCT/CN2016/074049
Other languages
French (fr)
Chinese (zh)
Inventor
郑龙
刘璐
Original Assignee
青岛海信宽带多媒体技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 青岛海信宽带多媒体技术有限公司 filed Critical 青岛海信宽带多媒体技术有限公司
Publication of WO2017045360A1 publication Critical patent/WO2017045360A1/en

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems

Definitions

  • the present invention relates to the field of optical communication technologies, and in particular, to an optical network unit of a passive optical network and an optical module thereof. Background technique
  • Asynchronous Transfer Mode, Asynchronous Transfer Mode APON (ATM Passive Optical Network) and BPON (Broadband Passive Optical Network) are severely blocked in commercialization and practical use. .
  • FSAN Full Service Access
  • GPON Gigabit Passive Optical Network
  • ITU International Telecommunication Union
  • GPON Gigabit Passive Optical Network
  • GPON has many advantages such as high bandwidth, high efficiency, large coverage, and support for multiple user interfaces.
  • GPON has excellent support for TDM (Time Division Multiplexing) services.
  • a GPON architecture generally includes: an OLT (Optical Line Terminal) and a plurality of ONUs (Optical Network) installed at a central office end
  • OLT optical network unit
  • ODN optical network
  • a plurality of optical modules are usually disposed in the OLT.
  • the optical modules in the OLT are connected to the ODN through optical fibers, and are used to transmit downlink optical signals or receive uplink optical signals.
  • An ONU is usually installed in the terminal.
  • An optical module is usually installed in the ONU.
  • the optical module in the ONU is connected to the ODN through an optical fiber to receive downlink optical signals or transmit uplink optical signals.
  • the optical module is usually connected to the communication system for converting the received optical signal into an electrical signal for transmission to the communication system for processing, or for receiving an electrical signal from the communication system to be converted into an optical signal and then transmitted through the optical fiber.
  • an existing GPON usually includes multiple optical modules.
  • a large number of optical modules suitable for GPON are required.
  • the cost of optical modules currently applicable to GPON is relatively high, resulting in high cost of deploying GPONs, which limits the large-scale promotion of GPON.
  • Embodiments of the present invention provide an optical network unit of a passive optical network and an optical module thereof for solving the disadvantages of high cost of deploying an existing GPON, so as to solve the problem that the existing GPON and its optical module have higher cost.
  • the problem The problem.
  • an optical module includes: a laser and a driving circuit thereof, and first and second resistors; a first resistor connected to an anode of the LED in the laser and the A second resistor is connected between the driving circuit and the cathode of the light emitting diode, and the optical module further includes:
  • a first low pass filter connected in parallel with the first resistor and connected between the anode of the light emitting diode and the driving circuit.
  • an optical network unit of a passive optical network is further provided, where the optical module includes: a laser and a driving circuit thereof, and first and second resistors; Between the anode of the LED and the driving circuit, the second resistor is connected between the cathode of the LED and the driving circuit, and the optical module further includes:
  • a first low pass filter connected in parallel with the first resistor and connected between the anode of the light emitting diode and the driving circuit.
  • a first low pass filter in the optical module is disposed between the driving circuit of the laser and the anode of the LED in the laser, and is connected in parallel with the first resistor to reduce the driving. Circuit
  • the load increases the bias current output by the driver circuit so that the laser can operate normally.
  • the first low pass filter suppresses the AC component in the bias current such that the frequency of the optical signal emitted by the laser is more stable.
  • the cost of the laser in the embodiment of the present invention is much lower than that of the DFB laser, and the price of the first low-pass filter is much smaller than the difference between the expensive DFB laser and the laser of the embodiment of the present invention, and thus the present invention
  • the cost of the optical module of the embodiment is much lower than the cost of the optical module using the DFB laser, and the cost of the ONU and the OLT of the optical module using the embodiment of the present invention can be reduced, thereby reducing the cost of deploying the PON on a large scale.
  • FIG. 1 is a schematic structural diagram of a passive optical network according to an embodiment of the present invention.
  • FIG. 2 is a schematic diagram of an internal circuit of an optical module according to an embodiment of the present invention.
  • FIG. 4 and FIG. 5 are respectively schematic diagrams showing internal circuits of first, second and third low-pass filters according to an embodiment of the present invention.
  • DFB distributed
  • optical modules in existing GPONs.
  • FeedBack, distributed feedback Lasers, and DFB lasers are expensive, resulting in high price of optical modules, resulting in high cost of large-scale deployment of GPON.
  • the inventors of the present invention have considered that a less expensive laser such as a FP (FabryPer ot) laser can be used instead of a relatively expensive DFB laser to reduce the cost of the optical module.
  • a less expensive laser such as a FP (FabryPer ot) laser can be used instead of a relatively expensive DFB laser to reduce the cost of the optical module.
  • the inventors of the present invention further found that in the optical module of the existing GPON, the bias current outputted by the driving circuit is usually transmitted to the DFB laser through only one resistor, and in the embodiment of the present invention, a low-cost laser is used.
  • the bias current required for this low cost laser is typically greater than the bias current required by the DFB laser.
  • the frequency deviation of the optical signal emitted by the laser of the embodiment of the present invention is easily caused, and the uplink light is affected. Signal transmission.
  • a low pass filter connected between the driver circuit and the laser is added, and the low pass filter is connected in parallel with the original resistor.
  • the inventors have found that the equivalent impedance of the low-pass filter in parallel with the resistor is less than the impedance of the resistor, which is equivalent to reducing the load of the driving circuit and increasing the bias current of the output of the driving circuit, which can satisfy the embodiment of the present invention.
  • the laser normally emits an optical signal.
  • the low pass filter can suppress the AC component in the bias current, and can make the DC component of the bias current delivered to the laser of the embodiment of the present invention more stable, thereby ensuring the frequency of the laser emitting optical signal. more stable.
  • FIG. 1 The schematic diagram of the architecture of a PON (Passive Optical Network) provided by the embodiment of the present invention is as shown in FIG. 1 , including: an OLT 101, multiple ONUs 102, and an ODN 103 connected between the OLT 101 and multiple ONUs 102. .
  • PON Passive Optical Network
  • the OLT 101 is usually disposed at the central office; the OLT 101 can be configured with multiple optical modules.
  • the optical module in the OLT 101 is connected to the ODN 103 through an optical fiber, and is used to transmit a downlink optical signal or receive an uplink optical signal.
  • the ONU 102 is usually disposed in the terminal; an optical module can be disposed in the ONU 102, and the optical module in the ONU 102 is connected to the ODN 103 through an optical fiber, and is configured to receive a downlink optical signal or transmit an uplink optical signal.
  • the optical module is usually connected to the communication system for converting the received optical signal into an electrical signal for transmission to the communication system for processing, or for receiving an electrical signal from the communication system to be converted into an optical signal and then transmitted through the optical fiber.
  • FIG. 2 A schematic diagram of an internal circuit of an optical module in the OLT 101 or the ONU 102 is as shown in FIG. 2, including: a laser 201 and its driving circuit 202, a first resistor 203 and a first low pass filter 204, and a second resistor 205.
  • the laser 201 may specifically be a FP (Fabry-Perot) laser or other laser cost lower than the DFB laser.
  • the laser 201 includes: a light emitting diode 211 and a photodiode 212.
  • the light emitting diode 211 may specifically be
  • the anode of the light emitting diode 211 is connected to the cathode of the photodiode 212.
  • the anode of photodiode 212 is in electrical communication with drive circuit 202.
  • the light-emitting diode 211 is used to perform electro-optical conversion through the bias current received by the cathode and the anode, and emits an optical signal.
  • the photodiode 212 is opposite to the LED 211 for receiving a part of the laser light emitted by the LED 211, and photoelectrically converting the received light to output a backlight current, which is fed back to the driving circuit 202 for the driving circuit 202 to adjust according to the backlight current.
  • the bias current is output to the light emitting diode 211, thereby adjusting the frequency, light intensity, and the like of the light signal emitted from the light emitting diode 211.
  • the first resistor 203 is connected between the driving circuit 202 and the anode of the light emitting diode 211 in the laser 201. That is, the first resistor 203 is also connected between the driving circuit 202 and the cathode of the photodiode 212. Preferably, the resistor 203 is coupled between the bias current output of the driver circuit 202 and the anode of the LED 211 in the laser 201.
  • the first low pass filter 204 is connected in parallel with the first resistor 203 and is connected between the anode of the light emitting diode 2 11 in the laser 201 and the driving circuit 202. That is, the first low pass filter 204 is also connected between the drive circuit 202 and the cathode of the photodiode 212. Preferably, the first low pass filter 204 is coupled between the bias current output of the driver circuit 202 and the anode of the LED 211 in the laser 201.
  • the second resistor 205 is connected between the driving circuit 202 and the cathode of the light emitting diode 211 in the laser 201.
  • the bias current outputted by the driving circuit 202 of the laser 201 is sent to the anode of the light-emitting diode 211 in the laser 201 through the parallel circuit of the resistor 203 and the first low-pass filter 204 for the laser 20 1
  • the LED 211 in the normal operation (ie, illumination).
  • the driving circuit 202 in the optical module never outputs a bias current to a state of outputting a bias current, and the bias current in the process From the beginning, there is a characteristic of alternating current, and the bias current in the process is mainly outputted to the light-emitting diode 211 and the photodiode 212 in the laser 201 through the first resistor 203, so that the laser 201 starts to enter the working state;
  • the bias current is mainly composed of a direct current component, and is transmitted to the light emitting diode 211 and the photodiode 212 in the laser 201 through a parallel circuit of the first resistor 203 and the first low pass filter 204.
  • the bias currents outputted by the driving circuit 202 a part of the bias current is supplied to the anode of the light emitting diode 211 and the cathode of the photodiode 212 in the laser 201 through the first low pass filter 204.
  • the first low pass filter 204 bias current, its AC component is converted into thermal energy dissipation through the first low pass filter 204, corresponding to the AC component of the partial bias current being first low pass.
  • the filter 204 suppresses such that the DC component of the bias current delivered to the anode of the LED 211 in the laser 201 is more stable, thereby making the frequency of the optical signal emitted by the LED 211 in the laser 201 more stable.
  • the optical module of the embodiment of the present invention further includes: a second low-pass filter 206 connected in parallel with the second resistor 205.
  • the second low pass filter 206 is connected between the cathode of the light emitting diode 211 in the optical module and the driving circuit 202.
  • the second low pass filter 206 may further filter the AC component of the bias current flowing through the second low pass filter 206 such that the loop is in the bias current from the cathode of the light emitting diode 211 to the driving circuit 202.
  • the DC component is more stable, so that the frequency of the optical signal emitted by the LED 211 in the laser 201 is more stable.
  • the optical module of the embodiment of the present invention further includes: a third low pass filter 207
  • the third low pass filter 207 is connected between the anode of the photodiode 212 in the laser 201 and the driving circuit 202.
  • the third low-pass filter 207 can suppress or filter the AC component of the backlight current outputted by the photodiode 212, so that the proportion of the DC component in the backlight current increases, and the driving circuit 202 can account for the DC component.
  • a larger backlight current more accurately adjusts the bias current output to the LED 211, so that the laser light intensity emitted by the LED 211 is more accurate and stable.
  • the current passed by the first low pass filter 204 or the second low pass filter 206 is not less than the bias current required for the LED 211 in the laser 201 to operate normally.
  • the first low pass filter 206 allows a current to pass no less than 70 mA (mA).
  • the driving current 202 of the laser 201 has a bias current of not less than 90 mA when its bias current output is unloaded.
  • the targeted selection of the cutoff frequency is lower than the determined
  • the low pass filter of the frequency is used as the first low pass filter 204.
  • the cutoff frequencies of the second low pass filter 206 and the third low pass filter 207 may both be lower than the determined frequency.
  • the cutoff frequency may be selected to be lower than 700 MHz.
  • the low pass filter acts as the first low pass filter 204.
  • a circuit in which a plurality of first low pass filters 204 connected in series are connected in parallel with the first resistor 203 may be employed. It is also possible to employ a circuit in which a plurality of second low-pass filters 206 connected in series are connected in parallel with the second resistor 205. Further, a circuit in which a plurality of third low-pass filters 207 are connected in series between the driving circuit 202 and the anode of the photodiode 212 can also be employed.
  • the amplitude of the AC component in the bias current supplied to the light-emitting diode 211 can be made 40 dB (decibel) or more lower than the amplitude of the DC component. Therefore, it can be considered that the AC component in the bias current has no influence on the frequency at which the light-emitting diode 211 outputs the optical signal.
  • the schematic diagram of the internal circuit of the first low-pass filter 204 is as shown in FIG. 3, and includes: a first inductor
  • a first capacitor 302 and a second capacitor 303 are connected to A first capacitor 302 and a second capacitor 303.
  • the first inductor 301 and the first capacitor 302 are both connected in parallel with the first resistor 203, and are connected between the anode of the LED 211 and the driving circuit 202.
  • the second capacitor 303 has one end connected between the first capacitor 301 and the driving circuit 202, and the other end of which is grounded.
  • the parameters of the first inductor 301, the first capacitor 302, and the second capacitor 303 are appropriately adjusted, so that the DC impedance of the first low-pass filter 204 is smaller than the impedance of the first resistor 203. Therefore, according to the characteristics of the parallel circuit, most of the bias current outputted by the driving circuit 202 is supplied to the anode of the light emitting diode 211 in the laser 201 through the first low pass filter 204, so that most of the AC component in the bias current is The low-pass filter suppresses or filters out, so that the proportion of the direct current component in the bias current is greater than the proportion of the alternating current component, and even several times the proportion of the alternating current component, the light-emitting diode 211 can account for a much larger proportion of the direct current component than the alternating current component.
  • the bias current output is more stable than the optical signal. For example, when the impedance of the resistor 203 is about 20 ⁇ , the DC impedance of the first low-pass filter 204
  • the schematic diagram of the internal circuit of the second low-pass filter 206 is as shown in FIG. 4, and includes: a second inductor 401, a third capacitor 402, and a fourth capacitor 403.
  • the second inductor 401 and the third capacitor 402 are both connected in parallel with the second resistor 205, and are connected between the anode of the LED 211 and the driving circuit 202.
  • One end of the fourth capacitor 403 is connected between the third capacitor 402 and the driving circuit 202, and the other end is grounded.
  • the parameters of the second inductor 401, the third capacitor 402, and the fourth capacitor 403 are appropriately adjusted, so that the DC impedance of the second low-pass filter 206 is smaller than the impedance of the second resistor 205. Thereafter, most of the bias current in the bias power loop from the cathode of the LED 211 to the driver circuit 202 will flow through the second low pass filter 206, which may further suppress or filter the bias.
  • the AC component in the current further increases the proportion of the DC component in the bias current, which is beneficial to the output of the LED 211 A more stable optical signal.
  • the schematic diagram of the internal circuit of the third low-pass filter 207 is as shown in FIG. 5, and includes: a third inductor 501, a fifth capacitor 502, and a sixth capacitor 503.
  • the third inductor 501 and the fifth capacitor 502 are connected in parallel, and are connected between the anode of the photodiode 212 in the laser 201 and the driving circuit 202.
  • One end of the sixth capacitor 503 is connected between the fifth capacitor 502 and the driving circuit 202, and the other end is grounded.
  • the parameters of the inductance and the capacitance in at least one of the first low pass filter 204, the second low pass filter 206, and the third low pass filter 207 are appropriately adjusted, and the driving can be adjusted.
  • the frequency response characteristic of the circuit 202 and the bias current loop before the laser 201 assists in optimizing the impedance matching of the peripheral circuit of the BOSA (Bi-Directional Optical Sub-Assembly) where the laser 201 or the laser 201 is located.
  • lasers in different optical modules may need to suppress or filter out AC components of different frequencies in the bias current to stably output optical signals of different frequencies.
  • the low pass filter may be appropriately adjusted.
  • the parameters of the inductor and capacitor are used to adjust the cutoff frequency of the low pass filter to suppress or filter the AC components of different frequencies in the bias current to accommodate the optical signals of the laser output at different frequencies. That is to say, the technical solution of the embodiment of the present invention can be applied to an optical module that requires outputting optical signals of different frequencies.
  • the ONU and its optical module in the embodiments of the present invention can be applied to GP0N, and can also be applied to EPON (Ethernet Passive Optical Network), XGP0N1, and XGP0N2. Or in passive optical networks such as NG-P0N2 (Next Generation-Passive Optical Network stage 2).
  • X in XGP0N1 is a number, for example, 10, and thus XGP0N1 is specifically 10GPON1.
  • the first low pass filter in the optical module is disposed between the driving circuit of the laser and the anode of the LED in the laser, and is connected in parallel with the first resistor to reduce the load of the driving circuit. , the bias current outputted by the driving circuit is increased, so that the laser can work normally. Also, the first low pass filter suppresses the AC component in the bias current such that the frequency of the optical signal emitted by the laser is more stable.
  • the cost of the laser in the embodiment of the present invention is much lower than that of the DFB laser, and the price of the first low-pass filter is much smaller than the difference between the expensive DFB laser and the laser of the embodiment of the present invention, and thus the present invention
  • the cost of the optical module of the embodiment is much lower than the cost of the optical module using the DFB laser, and the cost of the ONU and the OLT of the optical module using the embodiment of the present invention can be reduced, thereby reducing the cost of deploying the PON on a large scale.
  • a second low-pass filter is further disposed in the optical module in the embodiment of the present invention, which can further suppress or filter the AC component in the bias current; the third low-pass filter disposed in the optical module , can suppress or filter the AC component in the backlight current, and help the driving circuit to adjust the output to a more stable and accurate bias current according to the backlight current.
  • adjusting the parameters of the inductor and the capacitor in the low-pass filter in the embodiment of the present invention can adjust the frequency response characteristic of the bias current loop, and assist in optimizing the impedance matching of the laser peripheral circuit;
  • the cutoff frequency of the filter is adapted to the optical module that requires the output of optical signals of different frequencies.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Optical Communication System (AREA)
  • Semiconductor Lasers (AREA)

Abstract

Disclosed are an optical network unit of a passive optical network and optical module thereof. The optical module comprises: a laser and driving circuit therefor, and first and second resistors. The first resistor is connected between the anode of a light emitting diode in the laser and the driving circuit, and the second resistor is connected between the cathode of the light emitting diode and the driving circuit. The optical module further comprises: a first low-pass filter connected with the first resistor in parallel, and connected between the anode of the light emitting diode and the driving circuit. In the embodiments of the present invention, a bias current outputted by the driving circuit can enable the laser to work normally, and the first low-pass filter inhibits the alternating current component in the bias current, so that the frequency of the optical signal transmitted by the laser is more stable. Moreover, the costs of the laser in the embodiments of the present invention are far less than those of a DFB laser, and therefore, the costs of the optical module in the embodiments of the present invention are far less than those of the optical module using the DFB laser.

Description

无源光网络的光网络单元及其光模块 技术领域  Optical network unit of passive optical network and optical module thereof
[0001] 本发明涉及光线通信技术领域， 具体而言， 本发明涉及一种无源光网络的光网 络单元及其光模块。 背景技术  [0001] The present invention relates to the field of optical communication technologies, and in particular, to an optical network unit of a passive optical network and an optical module thereof. Background technique
[0002] 由于网络 IP (Internet Protocol, 因特网互联协议） 化进程迅速， 导致基于 ATM  [0002] Due to the rapid progress of the Internet Protocol (Internet Protocol), ATM-based
(Asynchronous Transfer Mode , 异步传输模式） 技术标准的 APON (ATM Passive Optical Network, 异步传输模式无源光网络） 和 BPON (Broadband Passive Optical Network, 宽带无源光网络） 在商用化和实用化方面严重受阻。  (Asynchronous Transfer Mode, Asynchronous Transfer Mode) APON (ATM Passive Optical Network) and BPON (Broadband Passive Optical Network) are severely blocked in commercialization and practical use. .
[0003] 在这样的背景下， FSAN (Full Service Access  [0003] In this context, FSAN (Full Service Access)
Network, 全业务接入网联盟) 和 ITU (international Telecommunication Union, 国际电信联盟） 以 APON/BPON的技术标准为基本框架， 重新设计了新的物理层 传输速率和传输汇聚层， 推出了 GPON (Gigabit Passive Optical Network， 吉比特 无源光网络） 技术标准。 GPON具有高带宽、 高效率、 大覆盖范围、 支持多种用 户接口等众多优点， 此外， GPON天然具有对 TDM (Time Division Multiplexing ， 吋分复用） 业务的优异支持能力。  Network, the full service access network alliance) and the ITU (international Telecommunication Union), based on the technical standards of APON/BPON, redesigned the new physical layer transmission rate and transmission convergence layer, and launched GPON (Gigabit). Passive Optical Network, Gigabit Passive Optical Network) technical standards. GPON has many advantages such as high bandwidth, high efficiency, large coverage, and support for multiple user interfaces. In addition, GPON has excellent support for TDM (Time Division Multiplexing) services.
[0004] 一种 GPON的架构， 通常包括： 设置在中心局端的 OLT (Optical Line Terminal ， 光线路终端） 、 多个 ONU (Optical Network  [0004] A GPON architecture generally includes: an OLT (Optical Line Terminal) and a plurality of ONUs (Optical Network) installed at a central office end
Unit, 光网络单元） ， 以及连接在 OLT与多个 ONU之间的 ODN (Optical Unit, optical network unit), and ODN (Optical) connected between the OLT and multiple ONUs
Distribution Network, 光配线网络） 。 OLT中通常设置有多个光模块， OLT中的 光模块通过光纤与 ODN相连， 用于发射下行光信号或接收上行光信号。 ONU通 常设置于终端， ONU中通常设置一个光模块， ONU中的光模块通过光纤与 ODN 相连， 用于接收下行光信号或发射上行光信号。 光模块通常与通讯***连接， 用于将接收的光信号转换为电信号发送至通讯***进行处理， 或者从通讯*** 接收电信号转换为光信号后通过光纤传输。 Distribution Network, Optical Distribution Network). A plurality of optical modules are usually disposed in the OLT. The optical modules in the OLT are connected to the ODN through optical fibers, and are used to transmit downlink optical signals or receive uplink optical signals. An ONU is usually installed in the terminal. An optical module is usually installed in the ONU. The optical module in the ONU is connected to the ODN through an optical fiber to receive downlink optical signals or transmit uplink optical signals. The optical module is usually connected to the communication system for converting the received optical signal into an electrical signal for transmission to the communication system for processing, or for receiving an electrical signal from the communication system to be converted into an optical signal and then transmitted through the optical fiber.
目前， GPON及后续技术标准的 PON (例如 XGPON) 被世界各国多数运营商和 FTTX (Fiber To The X, 光纤接入） 设备厂商视为实现接入网业务带宽化、 综合 化改造的理想接入网， 成为光接入网的主流。 At present, GPON and subsequent technical standards of PON (such as XGPON) are used by most operators in the world. FTTX (Fiber To The X, fiber access) device manufacturers are regarded as the ideal access network for bandwidth and integrated transformation of access network services, and become the mainstream of optical access networks.
[0006] 以 GPON为例， 现有的一个 GPON中通常包含多个光模块， 当大规模部署 GPON 吋， 需要海量的适用于 GPON的光模块。 然而， 目前适用于 GPON的光模块的成 本较高， 导致大规避部署 GPON的成本高昂， 限制了 GPON的大规模推广。 [0006] Taking GPON as an example, an existing GPON usually includes multiple optical modules. When a large-scale deployment of GPON, a large number of optical modules suitable for GPON are required. However, the cost of optical modules currently applicable to GPON is relatively high, resulting in high cost of deploying GPONs, which limits the large-scale promotion of GPON.
[0007] 因此， 有必要提供一种成本更低的无源光网络的光网络单元及其光模块， 以提 高竞争力。 [0007] Therefore, it is necessary to provide an optical network unit of a passive optical network with a lower cost and an optical module thereof to improve competitiveness.
技术问题  technical problem
[0008] 本发明的实施例针对部署现有的 GPON成本较高的缺点， 提出一种无源光网络 的光网络单元及其光模块， 用以解决现有的 GPON及其光模块成本较高的问题。 问题的解决方案  [0008] Embodiments of the present invention provide an optical network unit of a passive optical network and an optical module thereof for solving the disadvantages of high cost of deploying an existing GPON, so as to solve the problem that the existing GPON and its optical module have higher cost. The problem. Problem solution
技术解决方案  Technical solution
[0009] 本发明实施例根据一个方面， 提供了一种光模块， 包括： 激光器及其驱动电路 ， 以及第一、 二电阻； 第一电阻连接于所述激光器中的发光二极管的阳极与所 述驱动电路之间， 第二电阻连接于所述发光二极管的阴极与所述驱动电路之间 ， 所述光模块还包括：  According to an aspect of the present invention, an optical module includes: a laser and a driving circuit thereof, and first and second resistors; a first resistor connected to an anode of the LED in the laser and the A second resistor is connected between the driving circuit and the cathode of the light emitting diode, and the optical module further includes:
[0010] 第一低通滤波器， 与第一电阻相并联， 连接于所述发光二极管的阳极与所述驱 动电路之间。  And [0010] a first low pass filter connected in parallel with the first resistor and connected between the anode of the light emitting diode and the driving circuit.
[0011] 本发明实施例根据另一个方面， 还提供了一种无源光网络的光网络单元， 其光 模块包括： 激光器及其驱动电路， 以及以及第一、 二电阻； 第一电阻连接于所 述激光器中的发光二极管的阳极与驱动电路之间， 第二电阻连接于所述发光二 极管的阴极与所述驱动电路之间， 所述光模块， 还包括：  [0011] According to another aspect of the present invention, an optical network unit of a passive optical network is further provided, where the optical module includes: a laser and a driving circuit thereof, and first and second resistors; Between the anode of the LED and the driving circuit, the second resistor is connected between the cathode of the LED and the driving circuit, and the optical module further includes:
[0012] 第一低通滤波器， 与第一电阻相并联， 连接于所述发光二极管的阳极与所述驱 动电路之间。  And [0012] a first low pass filter connected in parallel with the first resistor and connected between the anode of the light emitting diode and the driving circuit.
发明的有益效果  Advantageous effects of the invention
有益效果  Beneficial effect
[0013] 本发明的实施例中， 光模块中的第一低通滤波器， 设置于激光器的驱动电路与 该激光器中发光二极管的阳极之间， 并与第一电阻相并联， 降低了该驱动电路 的负载， 增大了该驱动电路输出的偏置电流， 以使得该激光器可以正常工作。 并且， 第一低通滤波器抑制了偏置电流中的交流分量， 使得该激光器发射出的 光信号的频率更加稳定。 In an embodiment of the invention, a first low pass filter in the optical module is disposed between the driving circuit of the laser and the anode of the LED in the laser, and is connected in parallel with the first resistor to reduce the driving. Circuit The load increases the bias current output by the driver circuit so that the laser can operate normally. Also, the first low pass filter suppresses the AC component in the bias current such that the frequency of the optical signal emitted by the laser is more stable.
[0014] 而且， 本发明实施例中的激光器的成本远低于 DFB激光器， 第一低通滤波器的 价格远远小于昂贵的 DFB激光器与本发明实施例的激光器之间的差价， 因此本发 明实施例的光模块的成本远小于采用 DFB激光器的光模块的成本， 可以降低采用 本发明实施例的光模块的 ONU和 OLT的成本， 从而降低大规模部署 PON的成本 Moreover, the cost of the laser in the embodiment of the present invention is much lower than that of the DFB laser, and the price of the first low-pass filter is much smaller than the difference between the expensive DFB laser and the laser of the embodiment of the present invention, and thus the present invention The cost of the optical module of the embodiment is much lower than the cost of the optical module using the DFB laser, and the cost of the ONU and the OLT of the optical module using the embodiment of the present invention can be reduced, thereby reducing the cost of deploying the PON on a large scale.
[0015] 本发明附加的方面和优点将在下面的描述中部分给出， 这些将从下面的描述中 变得明显， 或通过本发明的实践了解到。 [0015] Additional aspects and advantages of the invention will be set forth in part in the description.
对附图的简要说明  Brief description of the drawing
附图说明  DRAWINGS
[0016] 本发明上述的和 /或附加的方面和优点从下面结合附图对实施例的描述中将变 得明显和容易理解， 其中：  [0016] The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from
[0017] 图 1为本发明实施例的无源光网络的架构示意图； 1 is a schematic structural diagram of a passive optical network according to an embodiment of the present invention;
[0018] 图 2为本发明实施例的光模块的内部电路的示意图； 2 is a schematic diagram of an internal circuit of an optical module according to an embodiment of the present invention;
[0019] 图 3、 图 4和图 5分别为本发明实施例的第一、 二、 三低通滤波器的内部电路的 示意图。  3, FIG. 4 and FIG. 5 are respectively schematic diagrams showing internal circuits of first, second and third low-pass filters according to an embodiment of the present invention.
本发明的实施方式 Embodiments of the invention
[0020] 下面详细描述本发明的实施例， 所述实施例的示例在附图中示出， 其中自始至 终相同或类似的标号表示相同或类似的元件或具有相同或类似功能的元件。 下 面通过参考附图描述的实施例是示例性的， 仅用于解释本发明， 而不能解释为 对本发明的限制。  The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are intended to be illustrative of the invention and are not to be construed as limiting.
[0021] 本技术领域技术人员可以理解， 除非特意声明， 这里使用的单数形式"一"、 " 一个"、 "所述 "和"该"也可包括复数形式。 应该进一步理解的是， 本发明的说明 书中使用的措辞"包括"是指存在所述特征、 整数、 步骤、 操作、 元件和 /或组件 ， 但是并不排除存在或添加一个或多个其他特征、 整数、 步骤、 操作、 元件、 组件和 /或它们的组。 应该理解， 当我们称元件被"连接"或"耦接"到另一元件吋 ， 它可以直接连接或耦接到其他元件， 或者也可以存在中间元件。 此外， 这里 使用的"连接"或"耦接"可以包括无线连接或无线耦接。 这里使用的措辞 "和 /或"包 括一个或更多个相关联的列出项的全部或任一单元和全部组合。 [0021] The singular forms "a", "an", "the" It will be further understood that the phrase "comprising", used in the <RTI ID=0.0></RTI><RTIgt;</RTI><RTIgt;</RTI><RTIgt;</RTI> is intended to mean the presence of the features, integers, steps, operations, components and/or components, but does not exclude the presence or addition of one or more other features, Integers, steps, operations, components, Components and/or their groups. It will be understood that when we refer to an element being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or an intermediate element can be present. Further, "connected" or "coupled" as used herein may include either a wireless connection or a wireless coupling. The phrase "and/or" used herein includes all or any of the elements and all combinations of one or more of the associated listed.
[0022] 本技术领域技术人员可以理解， 除非另外定义， 这里使用的所有术语 （包括技 术术语和科学术语） ， 具有与本发明所属领域中的普通技术人员的一般理解相 同的意义。 还应该理解的是， 诸如通用字典中定义的那些术语， 应该被理解为 具有与现有技术的上下文中的意义一致的意义， 并且除非像这里一样被特定定 义， 否则不会用理想化或过于正式的含义来解释。 [0022] Those skilled in the art will appreciate that all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs, unless otherwise defined. It should also be understood that terms such as those defined in a general dictionary should be understood to have meaning consistent with the meaning in the context of the prior art, and will not be idealized or excessive unless specifically defined as here. The formal meaning is explained.
[0023] 本发明的发明人发现， 现有的 GPON中的光模块中通常采用 DFB (Distributed [0023] The inventors of the present invention have found that DFB (Distributed) is commonly used in optical modules in existing GPONs.
FeedBack, 分布式反馈） 激光器， 而 DFB激光器的价格比较昂贵， 导致光模块价 格居高不下， 从而造成大规模部署 GPON的成本高昂。 FeedBack, distributed feedback) Lasers, and DFB lasers are expensive, resulting in high price of optical modules, resulting in high cost of large-scale deployment of GPON.
[0024] 本发明的发明人考虑到， 可以采用价格更为低廉的激光器， 例如 FP (FabryPer ot， 法布里珀罗） 激光器， 代替较为昂贵 DFB激光器， 以降低光模块的成本。  [0024] The inventors of the present invention have considered that a less expensive laser such as a FP (FabryPer ot) laser can be used instead of a relatively expensive DFB laser to reduce the cost of the optical module.
[0025] 本发明的发明人进一步发现， 现有的 GPON的光模块中， 驱动电路输出的偏置 电流通常仅通过一个电阻就输送到 DFB激光器， 而本发明实施例中采用低成本的 激光器， 该低成本的激光器所需的偏置电流通常大于 DFB激光器所需的偏置电流 。 当直接采用本发明实施例的激光器代替 DFB激光器吋， 本发明实施例的激光器 往往会得不到充足的偏置电流而无法正常工作。 而且， 即使本发明实施例的激 光器可以正常工作， 由于电阻无法抑制驱动电路输出的偏置电流中的交流分量 ， 很容易引起本发明实施例的激光器发射的光信号的频率偏移， 影响上行光信 号的传输。  [0025] The inventors of the present invention further found that in the optical module of the existing GPON, the bias current outputted by the driving circuit is usually transmitted to the DFB laser through only one resistor, and in the embodiment of the present invention, a low-cost laser is used. The bias current required for this low cost laser is typically greater than the bias current required by the DFB laser. When the laser of the embodiment of the present invention is used directly instead of the DFB laser, the laser of the embodiment of the present invention often does not have sufficient bias current to operate normally. Moreover, even if the laser of the embodiment of the present invention can work normally, since the resistor cannot suppress the AC component in the bias current output by the driving circuit, the frequency deviation of the optical signal emitted by the laser of the embodiment of the present invention is easily caused, and the uplink light is affected. Signal transmission.
[0026] 本发明的实施例中， 增加了连接于驱动电路与激光器之间的低通滤波器， 且使 得该低通滤波器与原有的电阻并联。 本发明人发现， 低通滤波器与电阻并联后 等效的阻抗小于电阻的阻抗， 相当于减小了驱动电路的负载， 增大了驱动电路 输出的偏置电流， 可以满足本发明实施例的激光器正常发射光信号。 而且， 低 通滤波器可以抑制偏置电流中的交流分量， 可以使得输送到本发明实施例的激 光器的偏置电流中的直流分量更加稳定， 从而保证该激光器发射光信号的频率 更加稳定。 In an embodiment of the invention, a low pass filter connected between the driver circuit and the laser is added, and the low pass filter is connected in parallel with the original resistor. The inventors have found that the equivalent impedance of the low-pass filter in parallel with the resistor is less than the impedance of the resistor, which is equivalent to reducing the load of the driving circuit and increasing the bias current of the output of the driving circuit, which can satisfy the embodiment of the present invention. The laser normally emits an optical signal. Moreover, the low pass filter can suppress the AC component in the bias current, and can make the DC component of the bias current delivered to the laser of the embodiment of the present invention more stable, thereby ensuring the frequency of the laser emitting optical signal. more stable.
[0027] 下面结合附图具体介绍本发明实施例的技术方案。  [0027] The technical solutions of the embodiments of the present invention are specifically described below with reference to the accompanying drawings.
[0028] 本发明实施例提供的 PON (Passive Optical Network, 无源光网络） 的架构示意 图如图 1所示， 包括： OLT101、 多个 ONU102, 以及连接在 OLT101与多个 ONU1 02之间的 ODN103。  [0028] The schematic diagram of the architecture of a PON (Passive Optical Network) provided by the embodiment of the present invention is as shown in FIG. 1 , including: an OLT 101, multiple ONUs 102, and an ODN 103 connected between the OLT 101 and multiple ONUs 102. .
[0029] 其中， OLT101通常设置在中心局端； OLT101中可以设置有多个光模块， OLT 101中的光模块通过光纤与 ODN103相连， 用于发射下行光信号或接收上行光信 号。  [0029] The OLT 101 is usually disposed at the central office; the OLT 101 can be configured with multiple optical modules. The optical module in the OLT 101 is connected to the ODN 103 through an optical fiber, and is used to transmit a downlink optical signal or receive an uplink optical signal.
[0030] ONU102通常设置于终端； ONU102中可以设置一个光模块， ONU102中的光模 块通过光纤与 ODN103相连， 用于接收下行光信号或发射上行光信号。  [0030] The ONU 102 is usually disposed in the terminal; an optical module can be disposed in the ONU 102, and the optical module in the ONU 102 is connected to the ODN 103 through an optical fiber, and is configured to receive a downlink optical signal or transmit an uplink optical signal.
[0031] 光模块通常与通讯***连接， 用于将接收的光信号转换为电信号发送至通讯系 统进行处理， 或者从通讯***接收电信号转换为光信号后通过光纤传输。 [0031] The optical module is usually connected to the communication system for converting the received optical signal into an electrical signal for transmission to the communication system for processing, or for receiving an electrical signal from the communication system to be converted into an optical signal and then transmitted through the optical fiber.
[0032] OLT101或者 ONU102中的光模块的内部电路的示意图如图 2所示， 包括： 激光 器 201及其驱动电路 202、 第一电阻 203和第一低通滤波器 204、 以及第二电阻 205 [0032] A schematic diagram of an internal circuit of an optical module in the OLT 101 or the ONU 102 is as shown in FIG. 2, including: a laser 201 and its driving circuit 202, a first resistor 203 and a first low pass filter 204, and a second resistor 205.
[0033] 其中， 激光器 201具体可以是 FP (Fabry-Perot, 法布里-珀罗） 激光器或者其他 成本低于 DFB激光器的激光器。 [0033] wherein the laser 201 may specifically be a FP (Fabry-Perot) laser or other laser cost lower than the DFB laser.
[0034] 激光器 201包括： 发光二极管 211和光电二极管 212。 发光二极管 211具体可以是[0034] The laser 201 includes: a light emitting diode 211 and a photodiode 212. The light emitting diode 211 may specifically be
FP激光二极管。 FP laser diode.
[0035] 发光二极管 211的阳极与光电二极管 212的阴极相连。 光电二极管 212的阳极与 驱动电路 202电路相通。  [0035] The anode of the light emitting diode 211 is connected to the cathode of the photodiode 212. The anode of photodiode 212 is in electrical communication with drive circuit 202.
[0036] 发光二极管 211用于通过其阴、 阳极接收到的偏置电流后， 进行电光转换， 发 射出光信号。 [0036] The light-emitting diode 211 is used to perform electro-optical conversion through the bias current received by the cathode and the anode, and emits an optical signal.
[0037] 光电二极管 212与发光二极管 211相对， 用于接收发光二极管 211发射出的一部 分激光， 对接收的光进行光电转换输出背光电流， 反馈至驱动电路 202， 供驱动 电路 202根据该背光电流调整输出到发光二极管 211的偏置电流， 从而调整发光 二极管 211发射出的光信号的频率和光强等。  The photodiode 212 is opposite to the LED 211 for receiving a part of the laser light emitted by the LED 211, and photoelectrically converting the received light to output a backlight current, which is fed back to the driving circuit 202 for the driving circuit 202 to adjust according to the backlight current. The bias current is output to the light emitting diode 211, thereby adjusting the frequency, light intensity, and the like of the light signal emitted from the light emitting diode 211.
[0038] 第一电阻 203连接于驱动电路 202与激光器 201中的发光二极管 211的阳极之间。 即第一电阻 203也连接于驱动电路 202与光电二极管 212的阴极之间。 较佳地， 电 阻 203连接于驱动电路 202的偏置电流输出端与激光器 201中的发光二极管 211的 阳极之间。 [0038] The first resistor 203 is connected between the driving circuit 202 and the anode of the light emitting diode 211 in the laser 201. That is, the first resistor 203 is also connected between the driving circuit 202 and the cathode of the photodiode 212. Preferably, the resistor 203 is coupled between the bias current output of the driver circuit 202 and the anode of the LED 211 in the laser 201.
[0039] 第一低通滤波器 204与第一电阻 203相并联， 连接于激光器 201中的发光二极管 2 11的阳极与驱动电路 202之间。 即第一低通滤波器 204也连接于驱动电路 202与光 电二极管 212的阴极之间。 较佳地， 第一低通滤波器 204连接于驱动电路 202的偏 置电流输出端与激光器 201中的发光二极管 211的阳极之间。  The first low pass filter 204 is connected in parallel with the first resistor 203 and is connected between the anode of the light emitting diode 2 11 in the laser 201 and the driving circuit 202. That is, the first low pass filter 204 is also connected between the drive circuit 202 and the cathode of the photodiode 212. Preferably, the first low pass filter 204 is coupled between the bias current output of the driver circuit 202 and the anode of the LED 211 in the laser 201.
[0040] 第二电阻 205连接于驱动电路 202与激光器 201中的发光二极管 211的阴极之间。  [0040] The second resistor 205 is connected between the driving circuit 202 and the cathode of the light emitting diode 211 in the laser 201.
[0041] 可见， 激光器 201的驱动电路 202输出的偏置电流， 通过电阻 203与第一低通滤 波器 204的并联电路， 输送到激光器 201中的发光二级管 211的阳极， 供激光器 20 1中的发光二极管 211正常工作 （即发光） 。  [0041] It can be seen that the bias current outputted by the driving circuit 202 of the laser 201 is sent to the anode of the light-emitting diode 211 in the laser 201 through the parallel circuit of the resistor 203 and the first low-pass filter 204 for the laser 20 1 The LED 211 in the normal operation (ie, illumination).
[0042] 具体地， 光模块接收到通讯***发送的光信号输出指令后， 该光模块中的驱动 电路 202从不输出偏置电流转换到输出偏置电流的状态， 此过程中的偏置电流从 无到有， 具有交流电流的特性， 此过程中的偏置电流主要通过第一电阻 203输出 到激光器 201中的发光二极管 211和光电二极管 212， 使得激光器 201幵始进入工 作状态； 待驱动电路 202输出的偏置电流稳定后， 偏置电流中以直流分量为主， 并通过第一电阻 203与第一低通滤波器 204的并联电路， 输送到激光器 201中的发 光二极管 211和光电二极管 212。  [0042] Specifically, after the optical module receives the optical signal output command sent by the communication system, the driving circuit 202 in the optical module never outputs a bias current to a state of outputting a bias current, and the bias current in the process From the beginning, there is a characteristic of alternating current, and the bias current in the process is mainly outputted to the light-emitting diode 211 and the photodiode 212 in the laser 201 through the first resistor 203, so that the laser 201 starts to enter the working state; After the bias current of the output of 202 is stabilized, the bias current is mainly composed of a direct current component, and is transmitted to the light emitting diode 211 and the photodiode 212 in the laser 201 through a parallel circuit of the first resistor 203 and the first low pass filter 204. .
[0043] 驱动电路 202输出的偏置电流中， 一部分偏置电流通过第一低通滤波器 204输送 到激光器 201中的发光二极管 211的阳极和光电二极管 212的阴极。 通过第一低通 滤波器 204的这一部分偏置电流， 其交流分量在通过第一低通滤波器 204吋被转 化成热能耗散， 相当于这部分偏置电流的交流分量被第一低通滤波器 204所抑制 ， 使得输送到激光器 201中的发光二极管 211阳极的偏置电流中的直流分量更加 稳定， 从而使得激光器 201中的发光二极管 211发射的光信号的频率更加稳定。  [0043] Of the bias currents outputted by the driving circuit 202, a part of the bias current is supplied to the anode of the light emitting diode 211 and the cathode of the photodiode 212 in the laser 201 through the first low pass filter 204. By this portion of the first low pass filter 204 bias current, its AC component is converted into thermal energy dissipation through the first low pass filter 204, corresponding to the AC component of the partial bias current being first low pass. The filter 204 suppresses such that the DC component of the bias current delivered to the anode of the LED 211 in the laser 201 is more stable, thereby making the frequency of the optical signal emitted by the LED 211 in the laser 201 more stable.
[0044] 较佳地， 如图 2所示， 本发明实施例的光模块中， 还包括： 与第二电阻 205并联 的第二低通滤波器 206。  Preferably, as shown in FIG. 2, the optical module of the embodiment of the present invention further includes: a second low-pass filter 206 connected in parallel with the second resistor 205.
[0045] 第二低通滤波器 206连接于光模块中的发光二极管 211的阴极与驱动电路 202之 间。 [0046] 第二低通滤波器 206可以进一步滤除流经第二低通滤波器 206的偏置电流的交流 分量， 使得回路中从发光二极管 211的阴极至驱动电路 202的偏置电流中的直流 分量更加稳定， 从而使得激光器 201中的发光二极管 211发射的光信号的频率更 加稳定。 [0045] The second low pass filter 206 is connected between the cathode of the light emitting diode 211 in the optical module and the driving circuit 202. The second low pass filter 206 may further filter the AC component of the bias current flowing through the second low pass filter 206 such that the loop is in the bias current from the cathode of the light emitting diode 211 to the driving circuit 202. The DC component is more stable, so that the frequency of the optical signal emitted by the LED 211 in the laser 201 is more stable.
[0047] 较佳地， 如图 2所示， 本发明实施例的光模块中， 还包括： 第三低通滤波器 207  [0047] Preferably, as shown in FIG. 2, the optical module of the embodiment of the present invention further includes: a third low pass filter 207
[0048] 第三低通滤波器 207连接于激光器 201中的光电二极管 212的阳极与驱动电路 202 之间。 The third low pass filter 207 is connected between the anode of the photodiode 212 in the laser 201 and the driving circuit 202.
[0049] 第三低通滤波器 207可以抑制或滤除光电二极管 212经过光电转换输出的背光电 流中的交流分量， 使得该背光电流中直流分量占比增加， 驱动电路 202可以根据 直流分量占比更大的背光电流， 更加准确地调整输出到发光二极管 211的偏置电 流， 从而使得发光二极管 211发射出的激光光强更加准确稳定。  [0049] The third low-pass filter 207 can suppress or filter the AC component of the backlight current outputted by the photodiode 212, so that the proportion of the DC component in the backlight current increases, and the driving circuit 202 can account for the DC component. A larger backlight current more accurately adjusts the bias current output to the LED 211, so that the laser light intensity emitted by the LED 211 is more accurate and stable.
[0050] 较佳地， 第一低通滤波器 204或第二低通滤波器 206允许通过的电流， 不小于激 光器 201中的发光二极管 211正常工作所需的偏置电流。 例如， 第一低通滤波器 2 04允许通过的电流不小于 70mA (毫安） 。  Preferably, the current passed by the first low pass filter 204 or the second low pass filter 206 is not less than the bias current required for the LED 211 in the laser 201 to operate normally. For example, the first low pass filter 206 allows a current to pass no less than 70 mA (mA).
[0051] 更优的， 激光器 201的驱动电流 202， 在其偏置电流输出端无负载的情况下， 输 出的偏置电流不小于 90mA。  More preferably, the driving current 202 of the laser 201 has a bias current of not less than 90 mA when its bias current output is unloaded.
[0052] 事实上， 可以预先通过实验确定出， 偏置电流中对激光器 201中的发光二极管 2 11发射光信号的频率容易产生影响的交流分量的频率； 针对性地选择截止频率 低于确定出的频率的低通滤波器作为第一低通滤波 204。 第二低通滤波器 206和 第三低通滤波器 207的截止频率都可以低于该确定出的频率。  [0052] In fact, it is possible to experimentally determine, in advance, the frequency of the AC component in the bias current that easily affects the frequency at which the light-emitting diode 2 11 in the laser 201 emits an optical signal; the targeted selection of the cutoff frequency is lower than the determined The low pass filter of the frequency is used as the first low pass filter 204. The cutoff frequencies of the second low pass filter 206 and the third low pass filter 207 may both be lower than the determined frequency.
[0053] 例如， 当确定出激光器 201中的发光二极管 211发送光信号的频率最容易受到偏 置电流中频率为 700-800MHZ (兆赫兹） 的交流分量的影响吋， 可以选择截止频 率低于 700MHz的低通滤波器作为第一低通滤波器 204。  [0053] For example, when it is determined that the frequency at which the light emitting diode 211 in the laser 201 transmits the optical signal is most susceptible to the AC component having a frequency of 700-800 MHz (megahertz) in the bias current, the cutoff frequency may be selected to be lower than 700 MHz. The low pass filter acts as the first low pass filter 204.
[0054] 在实际应用中， 可以采用将多个串联的第一低通滤波器 204与第一电阻 203相并 联的电路。 还可以采用将多个串联的第二低通滤波器 206与第二电阻 205相并联 的电路。 进一步， 还可以采用在驱动电路 202与光电二极管 212的阳极之间串联 多个第三低通滤波器 207的电路。 [0055] 根据实验验证， 采用上述至少一个串联有多个低通滤波器的电路， 可以使得提 供给发光二极管 211的偏置电流中交流分量的幅度比直流分量的幅度低 40dB (分 贝） 以上。 此吋， 可以认为偏置电流中交流分量， 对发光二极管 211输出光信号 的频率没有影响。 [0054] In practical applications, a circuit in which a plurality of first low pass filters 204 connected in series are connected in parallel with the first resistor 203 may be employed. It is also possible to employ a circuit in which a plurality of second low-pass filters 206 connected in series are connected in parallel with the second resistor 205. Further, a circuit in which a plurality of third low-pass filters 207 are connected in series between the driving circuit 202 and the anode of the photodiode 212 can also be employed. [0055] According to experimental verification, by using at least one of the above-described circuits having a plurality of low-pass filters connected in series, the amplitude of the AC component in the bias current supplied to the light-emitting diode 211 can be made 40 dB (decibel) or more lower than the amplitude of the DC component. Therefore, it can be considered that the AC component in the bias current has no influence on the frequency at which the light-emitting diode 211 outputs the optical signal.
[0056] 更优的， 第一低通滤波器 204的内部电路的示意图如图 3所示， 包括： 第一电感 [0056] More preferably, the schematic diagram of the internal circuit of the first low-pass filter 204 is as shown in FIG. 3, and includes: a first inductor
301、 第一电容 302和第二电容 303。 301. A first capacitor 302 and a second capacitor 303.
[0057] 其中， 第一电感 301和第一电容 302， 都与第一电阻 203相并联， 都连接于发光 二极管 211的阳极与驱动电路 202之间。 [0057] The first inductor 301 and the first capacitor 302 are both connected in parallel with the first resistor 203, and are connected between the anode of the LED 211 and the driving circuit 202.
[0058] 第二电容 303， 其一端连接于第一电容 301与驱动电路 202之间， 其另一端接地 [0058] The second capacitor 303 has one end connected between the first capacitor 301 and the driving circuit 202, and the other end of which is grounded.
[0059] 较佳地， 适当地调整第一电感 301、 第一电容 302和第二电容 303的参数， 可以 使得第一低通滤波器 204的直流阻抗小于第一电阻 203的阻抗。 此吋， 根据并联 电路的特性， 驱动电路 202输出的大部分偏置电流通过第一低通滤波器 204输送 到激光器 201中的发光二极管 211的阳极， 从而使得偏置电流中大部分交流分量 被低通滤波器抑制或者滤除， 使得偏置电流中直流分量的占比大于交流分量的 占比， 甚至几倍于交流分量的占比， 发光二极管 211可以根据直流分量占比远超 交流分量占比的偏置电流输出频率更加稳定的光信号。 例如， 当电阻 203的阻抗 为 20Ω左右吋， 可以将第一低通滤波器 204的直流阻抗调整为不大于 10Ω。 Preferably, the parameters of the first inductor 301, the first capacitor 302, and the second capacitor 303 are appropriately adjusted, so that the DC impedance of the first low-pass filter 204 is smaller than the impedance of the first resistor 203. Therefore, according to the characteristics of the parallel circuit, most of the bias current outputted by the driving circuit 202 is supplied to the anode of the light emitting diode 211 in the laser 201 through the first low pass filter 204, so that most of the AC component in the bias current is The low-pass filter suppresses or filters out, so that the proportion of the direct current component in the bias current is greater than the proportion of the alternating current component, and even several times the proportion of the alternating current component, the light-emitting diode 211 can account for a much larger proportion of the direct current component than the alternating current component. The bias current output is more stable than the optical signal. For example, when the impedance of the resistor 203 is about 20 Ω, the DC impedance of the first low-pass filter 204 can be adjusted to be not more than 10 Ω.
[0060] 更优的， 第二低通滤波器 206的内部电路的示意图如图 4所示， 包括： 第二电感 401、 第三电容 402和第四电容 403。  [0060] More preferably, the schematic diagram of the internal circuit of the second low-pass filter 206 is as shown in FIG. 4, and includes: a second inductor 401, a third capacitor 402, and a fourth capacitor 403.
[0061] 其中， 第二电感 401和第三电容 402， 都与第二电阻 205相并联， 都连接于发光 二极管 211的阳极与驱动电路 202之间。  [0061] The second inductor 401 and the third capacitor 402 are both connected in parallel with the second resistor 205, and are connected between the anode of the LED 211 and the driving circuit 202.
[0062] 第四电容 403的一端连接于第三电容 402与驱动电路 202之间， 另一端接地。  [0062] One end of the fourth capacitor 403 is connected between the third capacitor 402 and the driving circuit 202, and the other end is grounded.
[0063] 较佳地， 适当调整第二电感 401、 第三电容 402和第四电容 403的参数， 可以使 得第二低通滤波器 206的直流阻抗小于第二电阻 205的阻抗。 此吋， 偏置电力回 路中从发光二极管 211阴极至驱动电路 202段的大部分偏置电流将通过第二低通 滤波器 206流动， 第二低通滤波器 206可以进一步抑制或滤除偏置电流中的交流 分量， 使得偏置电流中直流分量的占比进一步提升， 有利于发光二极管 211输出 频率更加稳定的光信号。 Preferably, the parameters of the second inductor 401, the third capacitor 402, and the fourth capacitor 403 are appropriately adjusted, so that the DC impedance of the second low-pass filter 206 is smaller than the impedance of the second resistor 205. Thereafter, most of the bias current in the bias power loop from the cathode of the LED 211 to the driver circuit 202 will flow through the second low pass filter 206, which may further suppress or filter the bias. The AC component in the current further increases the proportion of the DC component in the bias current, which is beneficial to the output of the LED 211 A more stable optical signal.
[0064] 更优的， 第三低通滤波器 207的内部电路的示意图如图 5所示， 包括： 第三电感 501、 第五电容 502和第六电容 503。  [0064] More preferably, the schematic diagram of the internal circuit of the third low-pass filter 207 is as shown in FIG. 5, and includes: a third inductor 501, a fifth capacitor 502, and a sixth capacitor 503.
[0065] 其中， 第三电感 501和第五电容 502相并联， 都连接于激光器 201中的光电二极 管 212的阳极与驱动电路 202之间。  [0065] The third inductor 501 and the fifth capacitor 502 are connected in parallel, and are connected between the anode of the photodiode 212 in the laser 201 and the driving circuit 202.
[0066] 第六电容 503的一端连接于第五电容 502与驱动电路 202之间， 另一端接地。  [0066] One end of the sixth capacitor 503 is connected between the fifth capacitor 502 and the driving circuit 202, and the other end is grounded.
[0067] 更进一步， 适当地调整第一低通滤波器 204、 第二低通滤波器 206和第三低通滤 波器 207中至少一个低通滤波器中的电感和电容的参数， 可以调整驱动电路 202 与激光器 201之前的偏置电流回路的频率响应特性， 协助优化激光器 201、 或者 激光器 201所在的 BOSA (Bi-Directional Optical Sub-Assembly, 光发射接收组件 ) 的***电路的阻抗匹配。  [0067] Further, the parameters of the inductance and the capacitance in at least one of the first low pass filter 204, the second low pass filter 206, and the third low pass filter 207 are appropriately adjusted, and the driving can be adjusted. The frequency response characteristic of the circuit 202 and the bias current loop before the laser 201 assists in optimizing the impedance matching of the peripheral circuit of the BOSA (Bi-Directional Optical Sub-Assembly) where the laser 201 or the laser 201 is located.
[0068] 事实上， 不同光模块中的激光器， 可能需要抑制或滤除偏置电流中不同频率的 交流分量， 来稳定地输出不同频率的光信号。  [0068] In fact, lasers in different optical modules may need to suppress or filter out AC components of different frequencies in the bias current to stably output optical signals of different frequencies.
[0069] 本发明实施例中， 对于第一低通滤波器 204、 第二低通滤波器 206和第三低通滤 波器 207中任一低通滤波器， 可以通过适当调整该低通滤波器中电感和电容的参 数， 来调整该低通滤波器的截止频率， 从而抑制或滤除偏置电流中不同频率的 交流分量， 以适应激光器输出不同频率的光信号。 也就是说， 本发明实施例的 技术方案可以适用于要求输出不同频率光信号的光模块。  In the embodiment of the present invention, for any of the first low pass filter 204, the second low pass filter 206, and the third low pass filter 207, the low pass filter may be appropriately adjusted. The parameters of the inductor and capacitor are used to adjust the cutoff frequency of the low pass filter to suppress or filter the AC components of different frequencies in the bias current to accommodate the optical signals of the laser output at different frequencies. That is to say, the technical solution of the embodiment of the present invention can be applied to an optical module that requires outputting optical signals of different frequencies.
[0070] 本领域技术人员可以理解， 本发明实施例的 0NU及其光模块， 可以应用于 GP0 N中， 也可以应用于 EPON (Ethernet Passive Optical Network, 以太网无源光网络 ) 、 XGP0N1、 XGP0N2或 NG-P0N2 (Next Generation-Passive Optical Network stage2, 下一代无源光网络阶段 2) 等无源光网络中。 其中， XGP0N1中的 X为数 字， 例如 10， 此吋 XGP0N1具体为 10GPON1。  [0070] It can be understood by those skilled in the art that the ONU and its optical module in the embodiments of the present invention can be applied to GP0N, and can also be applied to EPON (Ethernet Passive Optical Network), XGP0N1, and XGP0N2. Or in passive optical networks such as NG-P0N2 (Next Generation-Passive Optical Network stage 2). Among them, X in XGP0N1 is a number, for example, 10, and thus XGP0N1 is specifically 10GPON1.
本发明的实施例中， 光模块中的第一低通滤波器， 设置于激光器的驱动电路与 该激光器中发光二极管的阳极之间， 并与第一电阻相并联， 降低了该驱动电路 的负载， 增大了该驱动电路输出的偏置电流， 以使得该激光器可以正常工作。 并且， 第一低通滤波器抑制了偏置电流中的交流分量， 使得该激光器发射出的 光信号的频率更加稳定。 [0072] 而且， 本发明实施例中的激光器的成本远低于 DFB激光器， 第一低通滤波器的 价格远远小于昂贵的 DFB激光器与本发明实施例的激光器之间的差价， 因此本发 明实施例的光模块的成本远小于采用 DFB激光器的光模块的成本， 可以降低采用 本发明实施例的光模块的 ONU和 OLT的成本， 从而降低大规模部署 PON的成本 In an embodiment of the invention, the first low pass filter in the optical module is disposed between the driving circuit of the laser and the anode of the LED in the laser, and is connected in parallel with the first resistor to reduce the load of the driving circuit. , the bias current outputted by the driving circuit is increased, so that the laser can work normally. Also, the first low pass filter suppresses the AC component in the bias current such that the frequency of the optical signal emitted by the laser is more stable. Moreover, the cost of the laser in the embodiment of the present invention is much lower than that of the DFB laser, and the price of the first low-pass filter is much smaller than the difference between the expensive DFB laser and the laser of the embodiment of the present invention, and thus the present invention The cost of the optical module of the embodiment is much lower than the cost of the optical module using the DFB laser, and the cost of the ONU and the OLT of the optical module using the embodiment of the present invention can be reduced, thereby reducing the cost of deploying the PON on a large scale.
[0073] 进一步， 本发明实施例中的光模块中还设置了第二低通滤波器， 可以进一步抑 制或滤除偏置电流中的交流分量； 该光模块中设置的第三低通滤波器， 可以抑 制或滤除背光电流中的交流分量， 有助于驱动电路根据该背光电流调整输出更 加稳定准确的偏置电流。 [0073] Further, a second low-pass filter is further disposed in the optical module in the embodiment of the present invention, which can further suppress or filter the AC component in the bias current; the third low-pass filter disposed in the optical module , can suppress or filter the AC component in the backlight current, and help the driving circuit to adjust the output to a more stable and accurate bias current according to the backlight current.
[0074] 此外， 调整本发明实施例中的低通滤波器中的电感和电容的参数， 可以调节偏 置电流回路的频率响应特性， 协助优化激光器***电路的阻抗匹配； 还可以调 整各低通滤波器的截止频率， 以适应要求输出不同频率的光信号的光模块。  In addition, adjusting the parameters of the inductor and the capacitor in the low-pass filter in the embodiment of the present invention can adjust the frequency response characteristic of the bias current loop, and assist in optimizing the impedance matching of the laser peripheral circuit; The cutoff frequency of the filter is adapted to the optical module that requires the output of optical signals of different frequencies.
[0075] 以上所述仅是本发明的部分实施方式， 应当指出， 对于本技术领域的普通技术 人员来说， 在不脱离本发明原理的前提下， 还可以做出若干改进和润饰， 这些 改进和润饰也应视为本发明的保护范围。  The above is only a part of the embodiments of the present invention, and it should be noted that those skilled in the art can make some improvements and refinements without departing from the principles of the present invention. And retouching should also be regarded as the scope of protection of the present invention.

Claims

权利要求书 Claim
[权利要求 1] 一种光模块， 包括： 激光器及其驱动电路， 以及第一、 二电阻； 第一 电阻连接于所述激光器中的发光二极管的阳极与所述驱动电路之间， 第二电阻连接于所述发光二极管的阴极与所述驱动电路之间， 其特征 在于， 还包括：  [Claim 1] An optical module, comprising: a laser and a driving circuit thereof, and first and second resistors; a first resistor connected between an anode of the LED in the laser and the driving circuit, and a second resistor Connecting between the cathode of the light emitting diode and the driving circuit, the method further includes:
第一低通滤波器， 与第一电阻相并联， 连接于所述发光二极管的阳极 与所述驱动电路之间。  A first low pass filter, coupled in parallel with the first resistor, is coupled between the anode of the light emitting diode and the drive circuit.
[权利要求 2] 根据权利要求 1所述的光模块， 其特征在于， 还包括：  The optical module according to claim 1, further comprising:
第二低通滤波器， 与第二电阻相并联， 连接于所述发光二极管的阴极 与所述驱动电路之间。  A second low pass filter is coupled in parallel with the second resistor and coupled between the cathode of the light emitting diode and the drive circuit.
[权利要求 3] 根据权利要求 2所述的光模块， 其特征在于， 还包括： [Claim 3] The optical module according to claim 2, further comprising:
第三低通滤波器， 连接于所述激光器中的光电二极管的阳极与所述驱 动电路之间；  a third low pass filter connected between the anode of the photodiode in the laser and the driving circuit;
其中， 所述光电二极管的阴极与所述发光二极管的阳极相连。  Wherein the cathode of the photodiode is connected to the anode of the light emitting diode.
[权利要求 4] 根据权利要求 1-3任一项所述的光模块， 其特征在于， 所述激光器具 体为法布里珀罗激光器。 The optical module according to any one of claims 1 to 3, wherein the laser body is a Fabry Perot laser.
[权利要求 5] 根据权利要求 3所述的光模块， 其特征在于， [Claim 5] The optical module according to claim 3, wherein
第一、 或者第二低通滤波器， 其截止频率低于 700MHz, 其允许通过 的电流不小于 70mA。  The first or second low pass filter has a cutoff frequency of less than 700 MHz, which allows a current of not less than 70 mA.
[权利要求 6] 根据权利要求 1所述的光模块， 其特征在于， 第一低通滤波器， 包括  [Claim 6] The optical module according to claim 1, wherein the first low pass filter includes
第一电感和第一电容， 都与第一电阻相并联， 都连接于所述发光二极 管的阳极与所述驱动电路之间； The first inductor and the first capacitor are both connected in parallel with the first resistor, and are connected between the anode of the light emitting diode and the driving circuit;
第二电容， 其一端连接于所述第一电容与所述驱动电路之间， 其另一 端接地。  The second capacitor has one end connected between the first capacitor and the driving circuit, and the other end of which is grounded.
[权利要求 7] 根据权利要求 2所述的光模块， 其特征在于， 第二低通滤波器， 包括  [Claim 7] The optical module according to claim 2, wherein the second low pass filter includes
第二电感和第三电容， 都与第二电阻相并联， 都连接于所述发光二极 管的阳极与所述驱动电路之间； The second inductor and the third capacitor are both connected in parallel with the second resistor, and are connected to the light emitting diode Between the anode of the tube and the drive circuit;
第四电容， 其一端连接于所述第三电容与所述驱动电路之间， 其另一 端接地。  The fourth capacitor has one end connected between the third capacitor and the driving circuit, and the other end of which is grounded.
[权利要求 8] —种无源光网络的光网络单元， 其光模块包括： 激光器及其驱动电路 [Claim 8] An optical network unit of a passive optical network, the optical module comprising: a laser and a driving circuit thereof
， 以及以及第一、 二电阻； 第一电阻连接于所述激光器中的发光二极 管的阳极与驱动电路之间， 第二电阻连接于所述发光二极管的阴极与 所述驱动电路之间， 其特征在于， 所述光模块， 还包括： And a first and second resistors; a first resistor is coupled between the anode of the light emitting diode in the laser and the driving circuit, and a second resistor is coupled between the cathode of the LED and the driving circuit, and characterized The optical module further includes:
第一低通滤波器， 与第一电阻相并联， 连接于所述发光二极管的阳极 与所述驱动电路之间。  A first low pass filter, coupled in parallel with the first resistor, is coupled between the anode of the light emitting diode and the drive circuit.
[权利要求 9] 根据权利要求 8所述的光网络单元， 其特征在于， 所述光模块， 还包 括：  The optical network unit according to claim 8, wherein the optical module further includes:
第二低通滤波器， 与第二电阻相并联， 连接于所述发光二极管的阴极 与所述驱动电路之间。  A second low pass filter is coupled in parallel with the second resistor and coupled between the cathode of the light emitting diode and the drive circuit.
[权利要求 10] 根据权利要求 9所述的光网络单元， 其特征在于， 所述光模块， 还包 括：  The optical network unit according to claim 9, wherein the optical module further includes:
第三低通滤波器， 连接于所述激光器中的光电二极管的阳极与所述驱 动电路之间；  a third low pass filter connected between the anode of the photodiode in the laser and the driving circuit;
其中， 所述光电二极管的阴极与所述发光二极管的阳极相连。  Wherein the cathode of the photodiode is connected to the anode of the light emitting diode.
PCT/CN2016/074049 2015-09-15 2016-02-18 Optical network unit of passive optical network and optical module thereof WO2017045360A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201510585899.2A CN106535010A (en) 2015-09-15 2015-09-15 Optical network unit of passive optical network, and optical module thereof
CN201510585899.2 2015-09-15

Publications (1)

Publication Number Publication Date
WO2017045360A1 true WO2017045360A1 (en) 2017-03-23

Family

ID=58288262

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/074049 WO2017045360A1 (en) 2015-09-15 2016-02-18 Optical network unit of passive optical network and optical module thereof

Country Status (2)

Country Link
CN (1) CN106535010A (en)
WO (1) WO2017045360A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6920446B2 (en) 2017-01-24 2021-08-18 華為技術有限公司Ｈｕａｗｅｉ Ｔｅｃｈｎｏｌｏｇｉｅｓ Ｃｏ．，Ｌｔｄ． Optical receiver
US11133647B2 (en) * 2018-09-20 2021-09-28 Source Photonics (Chengdu) Company, Ltd. Impedance matching circuit for optical transmitters and methods of making and using the same
CN114938243B (en) * 2022-07-22 2023-04-25 深圳市亿联无限科技有限公司 BOSA debugging method, system, debugger and debugging method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1993908A (en) * 2004-06-01 2007-07-04 波科海姆技术公共有限公司 Control circuitry in optoelectronic modules for laser crossing point adjustment
JP4228106B2 (en) * 2006-08-25 2009-02-25 Ｔｄｋ株式会社 High frequency superposition module for optical pickup
CN102386979A (en) * 2011-10-26 2012-03-21 常熟市高事达光电科技有限公司 Optical receiver uplink laser control circuit transformed by wired television bilateral network
CN104078841A (en) * 2014-07-08 2014-10-01 成都新易盛通信技术股份有限公司 Digital open loop temperature compensation system of optical module laser device

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04343491A (en) * 1991-05-21 1992-11-30 Nec Corp Optical transmitting circuit
JP2005317666A (en) * 2004-04-27 2005-11-10 Sumitomo Electric Ind Ltd Laser driving circuit
JP5306547B2 (en) * 2011-02-07 2013-10-02 三菱電機株式会社 Laser diode drive circuit
WO2013086674A1 (en) * 2011-12-12 2013-06-20 华为技术有限公司 Circuit for modulating optical time domain reflectometer test signal, and passive optical network system and device
CN104796800B (en) * 2011-12-31 2018-06-08 青岛海信宽带多媒体技术有限公司 Optical module and the passive optical network with the optical module

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1993908A (en) * 2004-06-01 2007-07-04 波科海姆技术公共有限公司 Control circuitry in optoelectronic modules for laser crossing point adjustment
JP4228106B2 (en) * 2006-08-25 2009-02-25 Ｔｄｋ株式会社 High frequency superposition module for optical pickup
CN102386979A (en) * 2011-10-26 2012-03-21 常熟市高事达光电科技有限公司 Optical receiver uplink laser control circuit transformed by wired television bilateral network
CN104078841A (en) * 2014-07-08 2014-10-01 成都新易盛通信技术股份有限公司 Digital open loop temperature compensation system of optical module laser device

Also Published As

Publication number Publication date
CN106535010A (en) 2017-03-22

Similar Documents

Publication Publication Date Title
US10432340B2 (en) Optical port auto-negotiation method, optical module, central office end device, and terminal device
CN101594184B (en) Optical line terminal
EP2944052B1 (en) Downstream burst transmission in passive optical networks
US20170064418A1 (en) Wavelength switching method, apparatus, and system
US20130094862A1 (en) Wavelength Management in Multiple-Wavelength Passive Optical Networks
US8483561B2 (en) Remote powering for FTTX via existing wire
WO2013020023A1 (en) Rogue optical network unit mitigation in multiple-wavelength passive optical networks
CN102523540B (en) Optical module and passive optical network with same
CN102511138B (en) Dimmable transceiver, passive optical network system and device
CN103891066B (en) Tunable optical NE
WO2017045360A1 (en) Optical network unit of passive optical network and optical module thereof
CN110192358B (en) Passive optical network system, optical component and matching impedance adjusting method thereof
EP2154832A1 (en) Optical access network
KR101762973B1 (en) Multi port PON Extender and method for transceiving optical signal using the multi port PON Extender
EP2209233A1 (en) Optical communications systems and optical line terminals
TWI765346B (en) Method for optical communication and optical-electrical-optical converter
KR100903121B1 (en) Optical link module of ONT/ONU with wavelength tuning function in WDM-PON, optical link system therefor, and method for wavelength tuning
WO2017173619A1 (en) Method of compensating driving current driving laser device, and associated device, assembly, and system
JP5942751B2 (en) Station side apparatus and optical communication network system for WDM / TDM-PON system
CN202395935U (en) Optical module and passive optical network with same
KR100919057B1 (en) Apparatus and method for GTC frame extraction of the GPON OLT
Ke et al. Burst-mode wavelength upconversion using gain-clamped SOA for applying WDM technique to TDM-PON
Kim et al. Cost-effective 16-channel frame-level BM-to-CM conversion GPON reach extender

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16845476

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16845476

Country of ref document: EP

Kind code of ref document: A1