JP2010161568A - Multi-rate passive optical network master station device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a master station device in a multi-rate TDMA-PON (Time Division Multiple Access-Passive Optical Network) system. <P>SOLUTION: The master station device includes: a filter 10 for dividing an incoming optical signal into an incoming high-speed optical signal and an incoming low-speed optical signal to output them when the incoming optical signal obtained by wavelength-multiplexing signals with different transmission speeds is inputted from a transmission line and on the other hand, multiplexing an outgoing high-speed optical signal and an outgoing low-speed optical signal to output the multiplexed signal to a transmission line when outgoing optical signals with different transmission speeds are inputted; a 10G optical transmitting and receiving part 20 for converting the incoming high-speed optical signal received from the filter 10 into an electric signal to output it, and converting the electric signal into an outgoing high-speed optical signal to output it to the filter 10; and a 1G optical transmitting and receiving part 50 for converting the incoming low-speed optical signal received from the filter 10 into an electric signal to output it, and converting the electric signal into an outgoing low-speed optical signal to output it to the filter 10. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a master station apparatus in a multi-rate TDMA-PON (Time Division Multiple Access-Passive Optical Network) system.

  In recent years, a PON (Passive Optical Network) system in which a master station device and a plurality of slave station devices are connected via a branching device (splitter) via a single-core transmission line (optical fiber) has been developed. At present, 1G-PON (1 gigabit-passive optical network) system that performs data communication at a transmission rate of 1 Gbps class for both uplink and downlink is rapidly spreading. With this spread, uplink and downlink transmission speed is 10 Gbps class. Studies of 10G-PON (10 gigabit-passive optical network) systems that have been speeded up have been started. Since the spread of the 10G-PON system depends on the subscription status to each PON system for each user, the transition to a new PON system proceeds on a user basis. For this reason, in the transition period to the new PON system, the combined use of 1G-PON and 10G-PON occurs.

  In a 1G-PON system, particularly a slave station device, an FP-LD (Fabry-Perot Laser Diode) having a low wavelength and a wide wavelength occupation band is used as a light source of an optical signal for uplink communication. Therefore, in the mixed PON system of 1G-PON and 10G-PON in the transition period of the PON system, there is a high possibility that the wavelengths of the upstream signals from the 1G slave station device and the 10G slave station device overlap. Therefore, in Patent Document 1 below, a TDMA (Time Division Multiple Access) wavelength-multiplexed 1 Gbps class optical signal and a 10 Gbps class optical signal are collectively received, and after receiving the optical signal, a 1 Gbps class signal and a 10 Gbps class signal are received. A multi-rate receiver having the function of separating has been proposed.

Japanese Patent Application Laid-Open No. 08-008954

  However, according to the conventional technique, in the conventional mixed PON system in which the wavelength bands of the 1G uplink signal and the 10G uplink signal overlap, it is necessary to multiplex the 1G uplink signal and the 10G uplink signal by the TDMA method. For this reason, there is a problem in that both the 1G upstream band and the 10G upstream band are limited.

  Further, according to the conventional technique, in the mixed PON system, it is necessary to multiplex the 1G uplink signal and the 10G uplink signal by the TDMA method. That is, it is necessary to allocate a time slot for a 1G uplink signal and a time slot for a 10G uplink signal by the same control unit, and a multi-rate PON MAC is required. For this reason, there is a problem in that 1G-PONMAC that has already been widely used cannot be used and the installation cost is high. In addition, the multi-rate PONMAC has a problem that the technical difficulty is high and the development cost increases compared to the PONMAC for a single transmission rate.

  Further, according to the above conventional technique, in the mixed PON system, it is necessary to collectively receive signals having different transmission rates with the same light receiving element in the receiver. Therefore, there is a problem that the design difficulty is high and the development cost is increased as compared with a receiver for a single transmission rate.

  Further, according to the conventional technique, the mixed PON system requires a multi-rate receiver as a master station device. For this reason, there has been a problem that it takes a laying cost to remove a 1G-PON master station device that has already been widely used and replace it with a master station device equipped with a multi-rate receiver.

  The present invention has been made in view of the above, and in a 1G / 10G mixed multi-rate PON system, is not subject to upstream signal bandwidth limitation, and facilitates the addition of a new 10G-PON master station device. It is an object of the present invention to obtain a multi-rate PON master station device that can easily realize system migration from a multi-rate TDMA-PON system to a 10G-PON system alone.

  In order to solve the above-described problems and achieve the object, the present invention is configured such that a plurality of slave station apparatuses and a master station apparatus are connected via an optical fiber, which is a single transmission line, via branching apparatuses, and have different transmission speeds. A master station apparatus in a multi-rate TDMA-PON system in which downstream optical signals having different transmission rates from upstream optical signals are wavelength-multiplexed in different wavelength bands, and signals having different transmission rates are wavelength-multiplexed from the transmission path. When an upstream optical signal is input, the upstream optical signal is separated into an upstream high-speed optical signal having a high transmission speed and an upstream low-speed optical signal having a low transmission speed, and the downstream optical signal having a different transmission speed is output. Filter means for combining, when input, a downstream high-speed optical signal that is an optical signal having a higher transmission speed and a downstream low-speed optical signal that is an optical signal having a lower transmission speed, and outputting the resultant signal to the transmission path; , The high-speed optical signal received from the filter means is converted into an electrical signal for output, the electrical signal is converted into a downstream high-speed optical signal and output to the filter means, and the optical signal is received from the filter means. And a low-speed optical signal transmitting / receiving unit that converts the upstream low-speed optical signal into an electrical signal and outputs the electrical signal, and converts the electrical signal into a downstream low-speed optical signal and outputs the signal to the filter unit.

  According to the present invention, there is an effect that it is possible to easily add a new 10G-PON master station device without being limited in the bandwidth of the uplink signal.

  Embodiments of a multi-rate PON master station apparatus according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
The multi-rate PON master station device (hereinafter referred to as a master station device) of the present embodiment is connected to a plurality of slave station devices via an optical fiber that is a single-core transmission path via a branch device. A multi-rate TDMA-PON system is configured in which upstream optical signals having different transmission rates and downstream optical signals having different transmission rates are wavelength-multiplexed in different wavelength bands. FIG. 1 is a diagram illustrating a configuration example of a master station apparatus according to the present embodiment. The master station apparatus includes a filter unit 10, a 10G optical transceiver unit 20, a 10G-PONMAC unit 30, a 10G-L2 switch unit 40, a 1G optical transceiver unit 50, a 1G-PONMAC unit 60, and a 1G-L2 switch. Unit 70.

  The filter unit 10 branches the received 1G / 10G uplink signal, combines the 1G downlink signal and the 10G downlink signal, and outputs the combined signal to the transmission path. The filter unit 10 includes a filter module unit 11 having a 1: 2 port. The filter module unit 11 branches the received 1G / 10G upstream signal. Also, the 1G downlink signal and the 10G downlink signal are combined and output to the transmission path. Specifically, the filter module unit 11 transmits light in the wavelength band shown in FIG. FIG. 2 is a diagram illustrating the wavelength arrangement of the 1G upstream / downstream signal and the 10G upstream / downstream signal and the characteristics of each filter. As shown in FIG. 2, the filter module unit 11 has a characteristic of transmitting (outputting) the band of the 1G upstream signal and the 1G downstream signal to one port. Further, it has a characteristic of transmitting (outputting) the band of the 10G upstream signal and the 10G downstream signal to the other port. Other characteristics in FIG. 2 will be described later.

  The 10G optical transceiver 20 transmits and receives optical signals in the 10G-PON system. The 10G optical transmission / reception unit 20 includes a 10G-BIDI (Bi Directional) unit 21, a transmission unit 22, a reception unit 23, and a BCDR (Burst Clock and Data Recovery) unit 24. In the present embodiment, a 10G-BIDI unit 21 is provided as a 10G optical module. The 10G-BIDI unit 21 converts a signal transmitted from its own device from an electric signal to an optical signal and outputs the signal. The optical signal from the filter unit 10 is received and converted into an electrical signal. The 10G-BIDI unit 21 includes a WDM (Wavelength Division Multiplexing) unit 211, a light emitting unit 212, a light receiving unit 213, and a connector unit 214. The WDM unit 211 performs transmission and reflection in the wavelength band shown in FIG. The high frequency band optical signal from the light emitting unit 212 is transmitted to the filter unit 10, and the low frequency band optical signal from the filter unit 10 is reflected to the light receiving unit 213. The light emitting unit 212 receives the electrical signal from the transmitting unit 22, converts it into an optical signal, and outputs it to the filter unit 10. The light receiving unit 213 receives the optical signal from the filter unit 10, converts it into an electrical signal, and outputs it to the receiving unit 23. The connector 214 is a junction with a wire (optical fiber) that inputs the optical signal from the filter unit 10 into the 10G-BIDI unit 21 and outputs the optical signal from the 10G-BIDI unit 21 to the filter unit 10. is there. The transmission unit 22 performs transmission processing for driving the light emitting unit 212 based on the electrical signal from the 10G-PONMAC unit 30. The receiving unit 23 performs an amplification process on the electric signal from the light receiving unit 213. The BCDR unit 24 separates a clock and data from an electric signal received in a burst manner and performs bit synchronization.

  The 10G-PON MAC unit 30 controls transmission / reception in the 10G-PON system. Specifically, bandwidth is allocated in TDMA at the time of transmission, and data is extracted from the electrical signal at the time of reception to perform demodulation processing. The 10G-L2 switch unit 40 performs transmission / reception with a server that provides the Internet or content in the 10G-PON system.

  The 1G optical transmission / reception unit 50 transmits / receives an optical signal in the 1G-PON system. The 1G optical transmission / reception unit 50 includes a 1G-BIDI unit 51, a transmission unit 52, a reception unit 53, and a BCDR unit 54. In the present embodiment, a 1G-BIDI unit 51 is provided as a 1G optical module. The 1G-BIDI unit 51 converts a signal transmitted from its own device from an electrical signal to an optical signal. The optical signal from the filter unit 10 is received and converted into an electrical signal. The 1G-BIDI unit 51 includes a WDM unit 211, a light emitting unit 512, a light receiving unit 513, and a connector unit 514. The light emitting unit 512 receives the electrical signal from the transmitting unit 52, converts it into an optical signal, and outputs it to the filter unit 10. The light receiving unit 513 receives the optical signal from the filter unit 10, converts it into an electrical signal, and outputs it to the transmission unit 53. The connector unit 514 is a junction with a wire (optical fiber) that inputs an optical signal from the filter unit 10 into the 1G-BIDI unit 51 and outputs an optical signal from the 1G-BIDI unit 51 to the filter unit 10. is there. The transmission unit 52 performs transmission processing for driving the light emitting unit 512 based on the electrical signal from the 1G-PON MAC unit 60. The receiving unit 53 performs amplification processing on the electrical signal from the light receiving unit 513. The BCDR unit 54 separates a clock and data from an electric signal received in a burst manner and performs bit synchronization.

  The 1G-PON MAC unit 60 controls transmission / reception in the 1G-PON system. Specifically, bandwidth is allocated in TDMA at the time of transmission, and data is extracted from the electrical signal at the time of reception to perform demodulation processing. The 1G-L2 switch unit 70 performs transmission / reception with a server that provides the Internet or content in the 1G-PON system.

  Next, the wavelength band of each signal used in the present embodiment will be described. As shown in FIG. 2, here, the wavelength band is 1260 to 1275 nm for the 10G upstream signal, 1285 to 1360 nm for the 1G upstream signal, 1480 to 1500 nm for the 1G downstream signal, and 1574 to 1580 nm for the 10G downstream signal. assign. In the present embodiment, the Video signal is not treated as a specific process, but 1550 to 1560 nm is assigned as a wavelength band because of a guide band relationship with adjacent signals (1G downlink signal and 10G downlink signal) described later.

  Originally, in GE-PON (Gigabit Ethernet (registered trademark) -Passive Optical Network) defined in IEEE 802.3-2005, wavelength bands of 1260 to 1360 nm are assigned as upstream signals and 1480 to 1500 nm as downstream signals. . In addition, in 10G-EPON (10 Gigabit-Ethernet (registered trademark) Passive Optical Network) defined by IEEE 802.3av Draft 2.0 PR30, a wavelength band of 1260 to 1280 nm as an upstream signal and 1574 to 1580 nm as a downstream signal is allocated. ing. In this embodiment, a light source that does not use the short wavelength side (1260 to 1385 nm) is used as the light source for the 1G upstream signal, and a light source that does not use the long wavelength side (1275-1380 nm) is used as the light source for the 10G upstream signal. Thus, the wavelength arrangement shown in FIG. 2 is made possible. This wavelength arrangement is based on the wavelength arrangement of GE-PON, which is a typical example of 1G-PON, and 10G-EPON, which is a typical example of 10G-PON, but is an example and is limited to this wavelength band. It is not a thing.

  In order to realize the characteristics shown in FIG. 2, for example, the filter module unit 11 has a guard band for branching / combining at 10 nm between 1275 and 1285 nm with an isolation of 40 dB or more, and a guard band at about 40 nm between 1500 to 1550 nm. Use a filter with an isolation of 40 dB or more. The WDM unit 211 uses a filter with a guard band of about 40 nm between 1360 nm and 1480 nm and an isolation of 40 dB or more.

  Next, optical signal transmission / reception processing in the master station apparatus will be described. First, a description will be given of a reception process when the master station apparatus receives an uplink signal mixed with 1G / 10G. In the 1G / 10G mixed system according to the present embodiment, the wavelengths of the 1G uplink signal and the 10G uplink signal are different, so that the optical signal from each 1G slave station device and each 10G slave station device is the PONMAC unit (1G-PONMAC). Unit 60, 10G-PON MAC unit 30) is assigned a time slot and is TDMA multiplexed. The master station device receives a 1G uplink signal and a 10G uplink signal that are asynchronously wavelength-multiplexed between 1G / 10G.

  When the master station device receives the 10G uplink signal, the filter module unit 11 of the filter unit 10 branches the 10G uplink signal and outputs it to the 10G-BIDI unit 21 of the 10G optical transceiver 20. The 10G-BIDI unit 21 reflects the 10G optical signal by the WDM unit 211 and distributes it to the light receiving unit 213 (for example, APD: Avalanche Photo Diode). The light receiving unit 213 receives an optical signal that is a 10G upstream signal, performs photoelectric conversion, and outputs an electrical signal to the receiving unit 23. Thereafter, the receiving unit 23 amplifies the electric signal, and the BCDR unit 24 separates the clock and data and performs bit synchronization, and then outputs the data to the 10G-PONMAC unit 30. The 10G-PON MAC unit 30 performs data processing for extracting and demodulating data from the received uplink signal. The 10G-L2 switch unit 40 performs transmission and reception with the Internet and a server that provides content based on the MAC address attached to the demodulated data.

  On the other hand, when the master station device receives the 1G upstream signal, the filter module unit 11 of the filter unit 10 branches the 1G upstream signal, and from a port different from the port that is output to the 10G-BIDI unit 21 of the 10G optical transceiver 20 The data is output to the 1G-BIDI unit 51 of the 1G optical transceiver unit 50. The 1G-BIDI unit 51 reflects the 1G optical signal by the WDM unit 211 and distributes it to the light receiving unit 513 (for example, APD). The light receiving unit 513 receives an optical signal that is a 1G upstream signal, performs photoelectric conversion, and outputs an electrical signal to the receiving unit 53. Thereafter, the receiving unit 53 amplifies the electric signal, and the BCDR unit 54 separates the clock and data and performs bit synchronization, and then outputs the data to the 1G-PON MAC unit 60. The 1G-PON MAC unit 60 performs data processing for extracting and demodulating data from the received uplink signal. The 1G-L2 switch unit 70 performs transmission / reception with a server that provides the Internet and content based on the MAC address attached to the demodulated data.

  Next, transmission processing when the master station device transmits a 10G downlink signal or a 1G downlink signal will be described. When the master station device transmits a 10G downlink signal, the 10G-L2 switch unit 40 transfers the 10G downlink signal to the 10G-PONMAC unit 30 when a 10G downlink signal is input from a server that provides the Internet or content. The 10G-PON MAC unit 30 performs bandwidth allocation in TDMA and outputs the result to the transmission unit 22. The transmission unit 22 drives the light emitting unit 212 (for example, EA / LD: Electro Absorption / Laser Diode) of the 10G-BIDI unit 21 according to the allocated band, and the light emitting unit 212 outputs an optical signal that is a 10G downlink signal. To do. The WDM unit 211 of the 10G-BIDI unit 21 transmits the 10G downstream optical signal from the light emitting unit 212 and outputs it to the filter unit 10. Here, the filter module unit 11 of the filter unit 10 combines the 10G downstream optical signal and the 1G downstream optical signal and outputs the combined signal to the transmission line.

  On the other hand, when the master station device transmits a 1G downlink signal, the 1G-L2 switch unit 70 transfers the 1G downlink signal to the 1G-PON MAC unit 60 when the 1G downlink signal is input from a server that provides the Internet or content. The 1G-PON MAC unit 60 performs bandwidth allocation in TDMA and outputs the result to the transmission unit 52. The transmission unit 52 drives a light emitting unit 512 (for example, DFB-LD: Distributed Feed Back-Laser Diode) of the 1G-BIDI unit 51 according to the allocated band, and the light emitting unit 512 transmits an optical signal that is a 1G downlink signal. Output. The WDM unit 211 of the 1G-BIDI unit 51 transmits the 1G downstream optical signal from the light emitting unit 512 and outputs it to the filter unit 10. Here, the filter module unit 11 of the filter unit 10 combines the 1G downstream optical signal and the 10G downstream optical signal and outputs them to the transmission line.

  As described above, in the present embodiment, a new wavelength separation / multiplexing filter unit and a 10G-PON master station device are applied while using the 1G-PON master station device as it is. As a result, in the 1G / 10G mixed multi-rate TDMA-PON system, it becomes possible to provide a master station device whose band is not limited for each uplink signal of 1G / 10G.

  In addition, BIDI is applied as the 10G optical module and the 1G optical module, and only one filter having the functions of a bandpass filter and a band rejection filter is applied as the filter unit. As a result, it is possible to reduce costs and save space, and it is possible to configure a master station apparatus that minimizes loss due to filter insertion for a 10G upstream / downstream signal with severe loss budget.

  The L2 switch unit is configured differently for 1G and 10G, but is not limited thereto. For example, one 1G / 10G-L2 switch unit capable of simultaneously performing 1G and 10G processing may be used. FIG. 3 is a diagram illustrating a configuration example of the master station device. 1 is different from the master station apparatus of FIG. 1 in that a 1G / 10G-L2 switch unit 80 is provided instead of the 10G-L2 switch unit 40 and the 1G-L2 switch unit 70. The 1G / 10G-L2 switch unit 80 performs transmission / reception with the Internet and a server that provides content for both the 1G-PON system and the 10G-PON system. By using one L2 switch, a simple configuration as a whole is possible. The transmission / reception process in each PON system when the 1G / 10G-L2 switch unit 80 is used is the same as the process described above.

Embodiment 2. FIG.
In this embodiment, the 10G optical module includes a 10G-TOSA unit and a 10G-ROSA unit. A different part from Embodiment 1 is demonstrated.

  FIG. 4 is a diagram illustrating a configuration example of the master station apparatus according to the present embodiment. The master station apparatus includes a filter unit 10a, a 10G optical transmission / reception unit 20a, a 10G-PONMAC unit 30, a 10G-L2 switch unit 40, a 1G optical transmission / reception unit 50, a 1G-PONMAC unit 60, and a 1G-L2 switch. Unit 70.

  The filter unit 10a branches the received 1G / 10G upstream signal, combines the 1G downstream signal and the 10G downstream signal, and outputs the combined signal to the transmission path. The filter unit 10a includes filter module units 12 and 13 having a 1: 2 port. The filter module unit 12 branches the received 1G / 10G uplink signal. Also, the combined 1G / 10G downlink signal is output to the transmission line. The filter module unit 13 outputs the 1G upstream signal to the 1G optical transmission / reception unit 50. Further, the 1G downstream signal and the 10G downstream signal are combined and output to the filter module unit 12. Specifically, the filter module units 12 and 13 transmit in the wavelength band shown in FIG. FIG. 5 is a diagram illustrating the wavelength arrangement of the 1G uplink signal and the 10G uplink signal and the characteristics of each filter. As shown in FIG. 5, the filter module unit 12 has a characteristic of transmitting (outputting) the band of the 10G upstream signal to one port and transmitting (outputting) the band other than the 10G upstream signal to the other port. The filter module unit 13 has a characteristic of transmitting (outputting) the band of the 10G downstream signal to one port and transmitting (outputting) the band of the 10G downstream signal to the other port.

  In order to realize the characteristics shown in FIG. 5, for example, the filter module unit 12 has a guard band for branching / combining of about 10 nm on the short wavelength side from 1260 nm and isolation of 40 dB or more, and a guard band of 10 nm between 1275 and 1285 nm. Then, a filter with an isolation of 40 dB or more is used. Further, the filter module unit 13 uses a filter with a guard band for branching / multiplexing of 10 nm between 1560 nm and 1574 nm at an isolation of 40 dB or more, and a guard band of about 10 nm on the longer wavelength side from 1580 nm with an isolation of 40 dB or more.

  The 10G optical transceiver 20a transmits and receives an optical signal in the 10G-PON system. The 10G optical transceiver 20a includes a 10G-TOSA (Transmitter Optical Sub-Assembly) 25, a transmitter 22, a 10G-ROSA (Receiver Optical Sub-Assembly) 26, a receiver 23, a BCDR 24, Is provided. In the present embodiment, a 10G-TOSA unit 25 and a 10G-ROSA unit 26 are provided as 10G optical modules. The 10G-TOSA unit 25 converts a signal transmitted from its own device from an electrical signal to an optical signal and outputs the signal. The 10G-TOSA unit 25 includes a light emitting unit 251 and a connector unit 252. The light emitting unit 251 receives the electrical signal from the transmitting unit 22, converts it into an optical signal, and outputs it to the filter unit 10a. The connector part 252 is a joint part with the wire (optical fiber) which outputs the optical signal from the inside of the 10G-TOSA part 25 to the filter part 10a. The 10G-ROSA unit 26 receives the optical signal from the filter unit 10a and converts it into an electrical signal. The 10G-ROSA unit 26 includes a light receiving unit 261 and a connector unit 262. The light receiving unit 261 receives the optical signal from the filter unit 10 a, converts it into an electrical signal, and outputs it to the receiving unit 23. The connector part 262 is a joint part with a cable (optical fiber) that inputs an optical signal from the filter part 10a into the 10G-ROSA part 26.

  Next, optical signal transmission / reception processing in the master station apparatus will be described. First, a description will be given of a reception process when the master station apparatus receives an uplink signal mixed with 1G / 10G. When the master station device receives the 10G uplink signal, the filter module unit 12 of the filter unit 10a branches the 10G uplink signal and outputs it to the 10G-ROSA unit 26 of the 10G optical transceiver 20a. In the 10G-ROSA unit 26, the light receiving unit 261 (for example, APD) receives an optical signal that is a 10G upstream signal, performs photoelectric conversion, and outputs an electrical signal to the receiving unit 23. The subsequent processing is the same as in the first embodiment.

  On the other hand, when the master station apparatus receives the 1G upstream signal, the filter module unit 12 of the filter unit 10a branches the 1G upstream signal and filters from a port different from the port output to the 10G-ROSA unit 26 of the 10G optical transceiver 20a. Output to the module unit 13. Further, the filter module unit 13 branches the 1G upstream signal and outputs it to the 1G-BIDI unit 51 of the 1G optical transceiver unit 50. The subsequent processing is the same as in the first embodiment.

  Next, transmission processing when the master station device transmits a 10G downlink signal or a 1G downlink signal will be described. When the master station device transmits the 10G downlink signal, the transmission unit 22 drives the light emitting unit 251 (for example, EA / LD) of the 10G-TOSA unit 25 according to the allocated band, and the light emitting unit 251 transmits the 10G downlink signal. Is output to the filter unit 10a. Here, the filter module unit 13 of the filter unit 10a combines the 10G downlink signal and the 1G downlink signal and outputs the combined signal to the filter module unit 12. The filter module unit 12 outputs the combined optical signal to the transmission line.

  On the other hand, when transmitting a 1G downstream signal, the WDM unit 211 of the 1G-BIDI unit 51 outputs an optical signal that is a 1G downstream signal from the light emitting unit 512 to the filter unit 10a. Here, the filter module unit 13 of the filter unit 10 a combines the 1G downlink signal and the 10G downlink signal and outputs the combined signal to the filter module unit 12. The filter module unit 12 outputs the combined optical signal to the transmission line.

  As described above, in the present embodiment, a new wavelength separation / multiplexing filter unit and a 10G-PON master station device are applied while using the 1G-PON master station device as it is. As a result, in the 1G / 10G mixed multi-rate TDMA-PON system, it becomes possible to provide a master station device whose band is not limited for each uplink signal of 1G / 10G.

  In addition, TOSA / ROSA is applied as the 10G optical module, BIDI is applied as the 1G optical module, and two filters having functions of a bandpass filter and a band rejection filter are applied as the filter unit. As a result, it is possible to flexibly configure the 10G optical transceiver, and it is possible to adopt a filter configuration with the least loss due to filter insertion for a 10G upstream signal with severe loss budget.

Embodiment 3 FIG.
In the present embodiment, two WDM units are provided as filter units. A different part from Embodiment 2 is demonstrated.

  FIG. 6 is a diagram illustrating a configuration example of the master station apparatus according to the present embodiment. The master station apparatus includes a filter unit 10b, a 10G optical transmission / reception unit 20a, a 10G-PONMAC unit 30, a 10G-L2 switch unit 40, a 1G optical transmission / reception unit 50, a 1G-PONMAC unit 60, and a 1G-L2 switch. Unit 70.

  The filter unit 10b branches the received 1G / 10G upstream signal, combines the 1G downstream signal and the 10G downstream signal, and outputs the combined signal to the transmission path. The filter unit 10b includes WDM units 14 and 15 having a 1: 2 port. The WDM unit 14 branches the received 1G / 10G uplink signal. Also, the combined 1G / 10G downlink signal is output to the transmission line. The WDM unit 15 outputs the 1G uplink signal to the 1G optical transmission / reception unit 50. Further, the 1G downstream signal and the 10G downstream signal are combined and output to the WDM unit 14. Specifically, the WDM units 14 and 15 perform transmission and reflection in the wavelength band shown in FIG. FIG. 7 is a diagram illustrating the wavelength arrangement of the 1G uplink signal and the 10G uplink signal and the characteristics of each filter. As shown in FIG. 7, the WDM unit 14 has a characteristic of reflecting a 10G upstream signal. Further, it has a characteristic of transmitting a signal in a band larger than the 10G upstream signal. The WDM unit 15 has a characteristic of transmitting a 10G downstream signal. Further, it has a characteristic of reflecting a signal in a band smaller than the 10G downstream signal.

  In order to realize the characteristics shown in FIG. 7, for example, the WDM unit 14 uses a filter having an isolation of 40 dB or more when the guard band for branching / combining is 10 nm between 1275-1285 nm. The WDM unit 15 uses a filter having an isolation of 40 dB or more when the guard band for branching / combining is 10 nm between 1560 and 1574 nm.

  Next, optical signal transmission / reception processing in the master station apparatus will be described. First, a description will be given of a reception process when the master station apparatus receives an uplink signal mixed with 1G / 10G. When the master station device receives the 10G uplink signal, the WDM unit 14 of the filter unit 10b reflects and branches the 10G uplink signal, and outputs it to the 10G-ROSA unit 26 of the 10G optical transceiver 20a. The subsequent processing is the same as in the second embodiment.

  On the other hand, when the master station apparatus receives the 1G uplink signal, the WDM unit 14 of the filter unit 10b transmits and branches the 1G uplink signal and is different from the port output to the 10G-ROSA unit 26 of the 10G optical transmission / reception unit 20a. To the WDM unit 15. Further, the WDM unit 15 reflects the 1G upstream signal and outputs it to the 1G-BIDI unit 51 of the 1G optical transmission / reception unit 50. The subsequent processing is the same as in the second embodiment.

  Next, transmission processing when the master station device transmits a 10G downlink signal or a 1G downlink signal will be described. When the master station device transmits a 10G downstream signal, the transmission unit 22 drives the light emitting unit 251 of the 10G-TOSA unit 25 according to the allocated band, and the light emitting unit 251 filters the optical signal that is the 10G downstream signal. To 10b. Here, the WDM unit 15 of the filter unit 10 b combines the 10G downlink signal and the 1G downlink signal and outputs the combined signal to the WDM unit 14. The WDM unit 14 outputs the combined optical signal to the transmission line.

  On the other hand, when transmitting a 1G downstream signal, the WDM unit 211 of the 1G-BIDI unit 51 outputs an optical signal that is a 1G downstream signal from the light emitting unit 512 to the filter unit 10b. Here, the WDM unit 15 of the filter unit 10 b combines the 1G downlink signal and the 10G downlink signal and outputs the combined signal to the WDM unit 14. The WDM unit 14 outputs the combined optical signal to the transmission line.

  As described above, in the present embodiment, a new wavelength separation / multiplexing filter unit and a 10G-PON master station device are applied while using the 1G-PON master station device as it is. As a result, in the 1G / 10G mixed multi-rate TDMA-PON system, it becomes possible to provide a master station device whose band is not limited for each uplink signal of 1G / 10G.

  Further, TOSA / ROSA is applied as a 10G optical module, BIDI is applied as a 1G optical module, and two WDM filters are applied as a filter unit. As a result, it is possible to flexibly configure the 10G optical transceiver, and it is possible to adopt a filter configuration with the least loss due to filter insertion for a 10G upstream signal with severe loss budget.

Embodiment 4 FIG.
In the present embodiment, a 1G optical module includes a 1G-TOSA unit and a 1G-ROSA unit, and further includes three WDM units as filter units, for a 10G uplink signal, a 1G uplink signal, and all optical signals. I / O is performed on different ports. A different part from Embodiment 3 is demonstrated.

  FIG. 8 is a diagram illustrating a configuration example of the master station apparatus according to the present embodiment. The master station device includes a filter unit 10c, a 10G optical transmission / reception unit 20a, a 10G-PONMAC unit 30, a 10G-L2 switch unit 40, a 1G optical transmission / reception unit 50a, a 1G-PONMAC unit 60, and a 1G-L2 switch. Unit 70.

  The filter unit 10c branches the received 1G / 10G uplink signal, combines the 1G downlink signal and the 10G downlink signal, and outputs the combined signal to the transmission path. The filter unit 10 c includes WDM units 14, 15, and 211. The WDM unit 211 reflects the 1G upstream signal and outputs it to the 1G-ROSA unit 56. Further, the 1G downstream signal is transmitted and output to the WDM unit 15. The characteristics of each WDM unit are the same as those in the third embodiment (see FIG. 7).

  The 1G optical transceiver 50a transmits and receives an optical signal in the 1G-PON system. The 1G optical transmission / reception unit 50a includes a 1G-TOSA unit 55, a transmission unit 52, a 1G-ROSA unit 56, a reception unit 53, and a BCDR unit 54. In this embodiment, a 1G-TOSA unit 55 and a 1G-ROSA unit 56 are provided as 1G optical modules. The 1G-TOSA unit 55 converts a signal transmitted from its own device from an electrical signal to an optical signal and outputs the signal. The 1G-TOSA unit 55 includes a light emitting unit 551 and a connector unit 552. The light emitting unit 551 receives the electrical signal from the transmitting unit 52, converts it into an optical signal, and outputs it to the filter unit 10c. The connector portion 552 is a joint portion with a wire (optical fiber) that outputs an optical signal from the inside of the 1G-TOSA portion 55 to the filter portion 10c. The 1G-ROSA unit 56 receives the optical signal from the filter unit 10c and converts it into an electrical signal. The 1G-ROSA unit 56 includes a light receiving unit 561 and a connector unit 562. The light receiving unit 561 receives the optical signal from the filter unit 10 c, converts it into an electrical signal, and outputs it to the receiving unit 53. The connector part 562 is a joint part with a wire (optical fiber) that inputs the optical signal from the filter part 10 c into the 1G-ROSA part 56.

  Next, optical signal transmission / reception processing in the master station apparatus will be described. First, a description will be given of a reception process when the master station apparatus receives an uplink signal mixed with 1G / 10G. When the master station device receives the 10G upstream signal, the WDM unit 14 of the filter unit 10c reflects and branches the 10G upstream signal, and outputs the branched signal to the 10G-ROSA unit 26 of the 10G optical transceiver 20a. The subsequent processing is the same as in the third embodiment.

  On the other hand, when the master station device receives the 1G uplink signal, the WDM unit 14 of the filter unit 10c transmits and branches the 1G uplink signal and is different from the port output to the 10G-ROSA unit 26 of the 10G optical transceiver 20a. To the WDM unit 15. Next, the WDM unit 15 reflects the 1G upstream signal and outputs it to the WDM unit 211. Further, the WDM unit 211 reflects the 1G upstream signal and outputs it to the 1G-ROSA unit 56 of the 1G optical transceiver 50a. In the 1G-ROSA unit 56, the light receiving unit 561 (for example, APD) receives the 1G upstream signal, performs photoelectric conversion, and outputs an electrical signal to the receiving unit 53. The subsequent processing is the same as in the third embodiment.

  Next, transmission processing when the master station device transmits a 10G downlink signal or a 1G downlink signal will be described. When the master station device transmits a 10G downstream signal, the transmission unit 22 drives the light emitting unit 251 of the 10G-TOSA unit 25 according to the allocated band, and the light emitting unit 251 filters the optical signal that is the 10G downstream signal. To 10c. Here, the WDM unit 15 of the filter unit 10c combines the 10G downlink signal and the 1G downlink signal and outputs the combined signal to the WDM unit 14. The WDM unit 14 outputs the combined optical signal to the transmission line.

  On the other hand, when transmitting a 1G downlink signal, the transmission unit 52 drives a light emitting unit 551 (for example, EA / LD) of the 1G-TOSA unit 55 according to the allocated band, and the light emitting unit 551 is a 1G downlink signal. The optical signal is output to the filter unit 10c. The WDM unit 211 of the filter unit 10c transmits the 1G downstream signal and outputs it to the WDM unit 15. Here, the WDM unit 15 combines the 1G downlink signal and the 10G downlink signal and outputs the combined signal to the WDM unit 14. The WDM unit 14 outputs the combined optical signal to the transmission line.

  As described above, in the present embodiment, a new wavelength separation / multiplexing filter unit and a 10G-PON master station device are applied while using the 1G-PON master station device as it is. As a result, in the 1G / 10G mixed multi-rate TDMA-PON system, it becomes possible to provide a master station device whose band is not limited for each uplink signal of 1G / 10G.

  Further, TOSA / ROSA is applied as the 10G optical module and 1G optical module, and three WDM filters are applied as the filter unit. As a result, both the 10G optical transmission / reception unit and the 1G optical transmission / reception unit can be configured flexibly, and a filter configuration with the least loss due to filter insertion can be taken for a 10G upstream signal with severe loss budget. It becomes.

  As described above, the multi-rate PON master station device according to the present invention is useful for a PON system, and is particularly suitable for a PON system in which 1G / 10G is mixed.

It is a figure which shows the structural example of a multi-rate PON master station apparatus. It is a figure which shows the wavelength arrangement | positioning of each signal, and the characteristic of a filter. It is a figure which shows the structural example of a multi-rate PON master station apparatus. It is a figure which shows the structural example of a multi-rate PON master station apparatus. It is a figure which shows the wavelength arrangement | positioning of each signal, and the characteristic of a filter. It is a figure which shows the structural example of a multi-rate PON master station apparatus. It is a figure which shows the wavelength arrangement | positioning of each signal, and the characteristic of a filter. It is a figure which shows the structural example of a multi-rate PON master station apparatus.

10, 10a, 10b, 10c Filter unit 11, 12, 13 Filter module unit 14, 15 WDM unit 20, 20a 10G optical transceiver unit 21 10G-BIDI unit 22 Transmitter unit 23 Receiver unit 24 BCDR unit 25 10G-TOSA unit 26 10G -ROSA unit 30 10G-PONMAC unit 40 10G-L2 switch unit 50, 50a 1G optical transmission / reception unit 51 1G-BIDI unit 52 transmission unit 53 reception unit 54 BCDR unit 55 1G-TOSA unit 56 1G-ROSA unit 60 1G-PONMAC unit 70 1G-L2 switch part 80 1G / 10G-L2 switch part 211 WDM part 212,251,512,551 Light-emitting part 213,261,513,561 Light-receiving part 214,252,262,514,552,562 connector part

Claims (10)

Multiple slave station devices and master station devices are connected via a branching device via an optical fiber that is a single-core transmission line, and upstream optical signals with different transmission rates and downstream optical signals with different transmission rates have different wavelengths in different wavelength bands. The master station device in a multiplexed multi-rate TDMA-PON system,
When an upstream optical signal in which signals having different transmission speeds are wavelength-multiplexed is input from the transmission path, the upstream optical signal is separated into an upstream high-speed optical signal having a high transmission speed and an upstream low-speed optical signal having a low transmission speed. On the other hand, when downstream optical signals having different transmission speeds are input, a downstream high-speed optical signal that is an optical signal with a higher transmission speed and a downstream low-speed optical signal that is an optical signal with a lower transmission speed are output. Filter means for combining and outputting to the transmission path;
A high-speed optical signal transmission / reception means for converting an upstream high-speed optical signal received from the filter means into an electrical signal and outputting the electrical signal;
A low-speed optical signal transmission / reception means for converting an upstream low-speed optical signal received from the filter means into an electrical signal and outputting the electrical signal, and converting the electrical signal into a downstream low-speed optical signal and outputting it to the filter means;
A multi-rate PON master station device comprising: The high-speed optical signal transmitting / receiving unit includes a high-speed BIDI type optical module, and converts the high-speed optical signal received from the filter unit into an electrical signal using the high-speed BIDI type optical module, and outputs the electrical signal. An electrical signal is converted into a downstream high-speed optical signal and output to the filter means,
The low-speed optical signal transmission / reception means includes a low-speed BIDI type optical module, converts the low-speed optical signal received from the filter means into an electrical signal using the low-speed BIDI type optical module, and outputs the electrical signal. An electrical signal is converted into a downstream low-speed optical signal and output to the filter means.
The multi-rate PON master station apparatus according to claim 1. The filter means includes
Outputting the upstream high-speed optical signal to a high-speed BIDI type optical module in the high-speed optical signal transmitting / receiving means, and outputting the upstream low-speed optical signal to the low-speed BIDI type optical module in the low-speed optical signal transmitting / receiving means;
A downstream high-speed optical signal from the high-speed BIDI type optical module and a downstream low-speed optical signal from the low-speed BIDI type optical module are combined and output to the transmission line;
The multi-rate PON master station apparatus according to claim 2, wherein The high-speed optical signal transmission / reception means includes a high-speed TOSA type optical module and a high-speed ROSA type optical module, and converts the electrical signal into a downstream high-speed optical signal using the high-speed TOSA type optical module and outputs it to the filter means. In addition, the upstream high-speed optical signal received from the filter means using the high-speed ROSA type optical module means is converted into an electrical signal and output.
The low-speed optical signal transmission / reception means includes a low-speed BIDI type optical module, converts the low-speed optical signal received from the filter means into an electrical signal using the low-speed BIDI type optical module, and outputs the electrical signal. An electrical signal is converted into a downstream low-speed optical signal and output to the filter means.
The multi-rate PON master station apparatus according to claim 1. The filter means includes
Outputting the upstream high-speed optical signal to the high-speed ROSA type optical module in the high-speed optical signal transmitting / receiving means, and outputting the upstream low-speed optical signal to the low-speed BIDI type optical module in the low-speed optical signal transmitting / receiving means;
Also, the downstream high-speed optical signal from the high-speed TOSA type optical module in the high-speed optical signal transmitting / receiving means and the downstream low-speed optical signal from the low-speed BIDI type optical module are combined and output to the transmission line.
The multi-rate PON master station device according to claim 4, wherein The high-speed optical signal transmission / reception means includes a high-speed TOSA type optical module and a high-speed ROSA type optical module, and converts the electrical signal into a downstream high-speed optical signal using the high-speed TOSA type optical module and outputs it to the filter means. In addition, the upstream high-speed optical signal received from the filter means using the high-speed ROSA type optical module is converted into an electrical signal and output.
The low-speed optical signal transmission / reception means includes a low-speed TOSA type optical module and a low-speed ROSA type optical module, converts an electrical signal into a downstream low-speed optical signal using the low-speed TOSA type optical module, and outputs it to the filter means In addition, the upstream low-speed optical signal received from the filter means using the low-speed ROSA type optical module is converted into an electrical signal and output.
The multi-rate PON master station apparatus according to claim 1. The filter means includes
Outputting the upstream high-speed optical signal to the high-speed ROSA type optical module in the high-speed optical signal transmitting / receiving means, and outputting the upstream low-speed optical signal to the low-speed ROSA type optical module in the low-speed optical signal transmitting / receiving means;
Further, the downstream high-speed optical signal from the high-speed TOSA type optical module in the high-speed optical signal transmission / reception unit and the downstream low-speed optical signal from the low-speed TOSA type optical module in the low-speed optical signal transmission / reception unit are combined to Output to the transmission line,
The multi-rate PON master station device according to claim 6. The filter means includes
When combining or separating signals in a desired wavelength band by connecting a plurality of filter configurations in multiple stages, the most loss budget among uplink high-speed optical signals, downlink high-speed optical signals, uplink low-speed optical signals, and downlink low-speed optical signals The multi-rate PON master station apparatus according to any one of claims 4 to 7, wherein a filter configuration of a multistage cascade connection with the least loss is applied to an optical signal having severe strictness. further,
A high-speed relay processing means for communicating with a server providing a service;
When an electrical signal is input from the high-speed optical signal transmitting / receiving means, data decoding processing is executed and output to the high-speed relay processing means, and when an electrical signal is input from the high-speed relay processing means A high-speed optical signal control means for performing band allocation in a wavelength band for transmitting a downstream high-speed optical signal and outputting the band to the high-speed optical signal transmitting / receiving means;
A low-speed relay processing means for communicating with a server providing a service;
When an electrical signal is input from the low-speed optical signal transmitting / receiving means, data decoding processing is executed and output to the low-speed relay processing means, and when an electrical signal is input from the low-speed relay processing means Low-speed optical signal control means for performing allocation of the band in the wavelength band for transmitting the downstream low-speed optical signal and outputting to the low-speed optical signal transmitting / receiving means;
The multi-rate PON master station device according to any one of claims 1 to 8, further comprising: further,
Relay processing means for communicating with a server providing a service;
When an electrical signal is input from the high-speed optical signal transmitting / receiving means, data decoding processing is performed and output to the relay processing means, and when an electrical signal is input from the relay processing means, a downstream high-speed optical signal is output. A high-speed optical signal control unit that performs band allocation in a wavelength band to be transmitted and outputs the band to the high-speed optical signal transmission / reception unit;
When an electrical signal is input from the low-speed optical signal transmission / reception means, a data decoding process is performed and output to the relay processing means, and when an electrical signal is input from the relay processing means, a downstream low-speed optical signal is output. A low-speed optical signal control means for performing band allocation in the wavelength band to be transmitted and outputting to the low-speed optical signal transmission / reception means;
The multi-rate PON master station device according to any one of claims 1 to 8, further comprising:

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