TRANSMISSION DEVICE, FUNCTION CONTROL DEVICE, SYSTEM, AND SIGNAL PROCESSING METHOD

Abstract

This transmission device comprises a scheme identification unit, a function control unit, and a signal processing unit. On the basis of a characteristic of a received signal, the scheme identification unit identifies at least one among a modulation scheme, a frame format, and an encoding scheme. The function control unit provides control so as to cause a signal processing fuction to be performed, said signal processing function corresponding to the identification result from the scheme identification unit regarding at least one among a modulation scheme, a frame format, and an encoding scheme. The signal processing unit is controlled by the function control unit so as to operate, and processes the received signal.

Description

[Technical field]

[0001] The present invention relates to a transmission device, a function control device, a system, and a signal processing method. [Background technology]

[0002] Conventional equipment configurations for optical access systems include (a) an Ethernet frame receiver with a media converter (MC) interface, (b) a passive optical network (PON) specification frame receiver with a PON interface, and (c) a digital signal processing receiver with an analog-to-digital converter (ADC).

[0003] Conventionally, different devices such as the above types (a), (b), and (c) have been used depending on the transmission service to be realized. Non-Patent Document 1 describes a receiving device of type (b). Non-Patent Document 2 describes a receiving device of type (c).

[0004] In addition, in the prior art, there is a method of changing functions to optimize the demodulation method or FEC decoding method (FEC is an abbreviation for Forward Error Correction) according to the transmission state. For example, there is a method of switching between a function of demodulating a received signal with QPSK and a function of demodulating with 16QAM according to the transmission state. Non-Patent Document 3 describes such a receiving device.

[0005] Furthermore, in the prior art, there is a method that allows one device to change the ON / OFF of the FEC function. In this method, it is necessary to negotiate between devices regarding the change of ON / OFF of FEC. There are methods for negotiation, such as a method of putting information about ON / OFF of FEC in the preamble of a transmission frame, and a method of measuring the bit error rate at the ONU after transmitting a frame once from the OLT, and determining ON / OFF of FEC based on the measured bit error rate. Note that OLT is an abbreviation for "Optical Line Terminal" and is an optical line terminal device on the telecommunications carrier side. Also, ONU is an abbreviation for "Optical Network Unit" and is an optical line terminal device on the subscriber side. Non-Patent Document 4 describes a device that changes ON / OFF of FEC as described above.

[0006] In addition, in the prior art, there is a method for identifying the modulation method in order to monitor the state of the received signal. In this method, a histogram of the amplitude of the received signal is created, and the modulation method is identified using a neighborhood search or the like. Non-Patent Document 5 describes a technique for identifying the modulation method as described above.

[0007] Also, in the prior art, there is a method of using a digital coherent transmitter and receiver that performs polarization multiplexing. In this method, the transmitter separates the signal light into X- and Y-polarized waves, modulates each of the polarized waves, combines them, and transmits them to the receiver. In the receiver, the signal is received by a coherent receiver and separated into information on the optical complex amplitude in the X and Y directions. After that, clock synchronization and signal detection are performed, followed by polarization separation and filtering. After polarization separation and filtering, carrier recovery and decoding are performed on the signals that were separated into the X- and Y-polarized waves at the time of modulation. [Prior art documents] [Non-patent literature]

[0008]

Non-patent document 1

Non-patent document 2

Non-patent document 3

Non-patent document 4

[0009] The above-described conventional techniques have the following problems.

[0010] In a method in which different devices (the configurations of Non-Patent Document 1 and Non-Patent Document 2) are used depending on the transmission service to be realized, it becomes necessary to replace the devices when changing the transmission service.

[0011] Although it is possible to switch functions as in the technology described in Non-Patent Document 3, there was no method for selecting an appropriate demodulation method and encoding method according to the received signal.

[0012] The method of switching transmission functions (FEC ON / OFF, etc.) as described in Non-Patent Document 4 requires sending and receiving frames with a special configuration, and communication cannot be performed using any protocol, resulting in a problem of system complexity. In other words, since negotiation of transmission functions is required between two communication devices, a sequence for this needs to be implemented, resulting in system complexity. Another problem is that overhead time is generated when switching transmission functions.

[0013] The technology described in Non-Patent Document 5 can identify the modulation method of a received signal, but does not realize a method for switching the demodulation method or the encoding method according to the received signal. Also, a method for identifying the modulation method in real time in a receiving device has not been considered. In addition, there is a problem that the identification rate of the modulation method deteriorates when the influence of noise in the communication channel increases.

[0014] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a transmission device, a function control device, a system, and a signal processing method that can correctly process signals according to various methods (modulation methods, frame formats, encoding methods) using a single type of device, without having to use multiple types of devices. [Means for solving the problem]

[0015] In order to solve the above problems, a transmission device according to one embodiment of the present invention comprises a scheme identification unit that identifies at least one of a modulation scheme, a frame format, and an encoding scheme based on characteristics of a received signal, a function control unit that controls the operation of a signal processing function according to the identification result of the scheme identification unit between at least one of the modulation scheme, the frame format, and the encoding scheme, and a signal processing unit that is controlled to operate by the function control unit and processes the received signal.

[0016] In addition, a function control device according to one embodiment of the present invention includes a function control unit that receives from a transmission device information on an identification result regarding at least one of a modulation method, a frame format, and an encoding method identified based on the characteristics of a signal received by the transmission device, and controls the transmission device to operate a signal processing function corresponding to the received identification result.

[0017] Moreover, a system according to one aspect of the present invention is a system including a terminal device and a transmission device, the terminal device transmitting a signal to the transmission device, the transmission device including a scheme identification unit that identifies at least one of a modulation scheme, a frame format, and an encoding scheme based on a characteristic of a signal received from the terminal device, a function control unit that controls the operation of a signal processing function according to the identification result of the scheme identification unit of at least one of the modulation scheme, the frame format, and the encoding scheme, and a signal processing unit that is controlled to operate by the function control unit and processes the received signal.

[0018] In addition, a signal processing method according to one aspect of the present invention is such that a scheme identification unit identifies at least one of a modulation scheme, a frame format, and an encoding scheme based on characteristics of a received signal, a function control unit controls the scheme identification unit to operate a signal processing function corresponding to the identification result of at least one of the modulation scheme, the frame format, and the encoding scheme, and a signal processing unit is controlled by the function control unit to operate a signal processing function corresponding to the identification result, and processes the received signal. Effect of the Invention

[0019] According to the present invention, it becomes possible to correctly process signals according to various methods (modulation methods, frame formats, encoding methods) using one type of device, without having to use a plurality of types of devices. [Brief description of the drawings]

[0020] [Figure 1]1 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a first embodiment of the present invention. [Diagram 2] 1 is a block diagram showing a schematic device configuration of a communication system configured using a station side device according to a first embodiment. [Diagram 3] FIG. 11 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a second embodiment. [Figure 4] FIG. 11 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a third embodiment. [Diagram 5] FIG. 13 is a block diagram showing the internal functional configurations of a modulation scheme identifying unit, a frame identifying unit, and an encoding identifying unit in a third embodiment. [Figure 6] FIG. 13 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a fourth embodiment. [Figure 7] FIG. 13 is a block diagram showing the internal functional configuration of a frame identification unit in the fourth embodiment. [Figure 8] FIG. 13 is a block diagram showing the internal functional configuration of a coding identification unit in a fourth embodiment. [Figure 9] FIG. 13 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a fifth embodiment. [Figure 10] FIG. 13 is a schematic diagram showing a configuration example (first example) of data stored in an encoding method storage unit in the fifth embodiment. [Figure 11] FIG. 23 is a schematic diagram showing a configuration example (second example) of data stored in an encoding method storage unit in the fifth embodiment. [Figure 12] FIG. 23 is a schematic diagram showing a configuration example (third example) of data stored in an encoding method storage unit in the fifth embodiment. [Figure 13] FIG. 23 is a schematic diagram showing a configuration example (fourth example) of data stored in an encoding method storage unit in the fifth embodiment. [Figure 14] FIG. 13 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to a sixth embodiment. [Figure 15]FIG. 23 is a block diagram showing a schematic functional configuration of a station side device (transmission device) according to the seventh embodiment. [Figure 16] FIG. 23 is a block diagram showing a more detailed functional configuration for realizing the functions of polarization separation, adaptive filtering, and modulation method identification in the station building device according to the seventh embodiment. [Figure 17] FIG. 23 is a block diagram showing a configuration of an adaptive filter included in a station side device according to the seventh embodiment. [Figure 18] FIG. 23 is a block diagram showing a functional configuration for modulation scheme identification included in a station side device according to the eighth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In the following, a number of embodiments of the present invention will be described with reference to the drawings. Note that, as long as there is no contradiction in the combination, the features of the multiple embodiments described below may be appropriately combined and implemented.

[0022] [First embodiment] 1 is a block diagram showing a schematic functional configuration of a transmission device (called station-side device 1) according to the first embodiment. As shown in the figure, station-side device 1 includes a signal acquisition unit 101, a method identification unit 102, a DSP demodulation unit 106, a decoding unit 107, and an orchestrator 108.

[0023] Each functional unit constituting the station side device 1 is configured using, for example, at least one of an optical circuit using optical elements and an electronic circuit using electronic elements. At least a part of the functions of each functional unit may be realized by a computer (arithmetic device) and a program. Also, at least a part of the functions of each functional unit may be realized as a dedicated electronic circuit or optical circuit. Each functional unit has a storage means as necessary. For example, a semiconductor memory or an optical memory is used as the storage means. When a relatively slow information access speed is acceptable, a magnetic disk device may be used as the storage means.

[0024] The station side device 1 is, for example, a device provided in a station of a telecommunications carrier. The station side device 1 communicates with a user terminal device 2. The station side device 1 can communicate with a plurality of user terminal devices 2 using different methods. In the illustrated example, the station side device 1 communicates with each of the user terminal devices 2A, 2B, and 2C. For example, the station side device 1 communicates with the user terminal device 2A using a QPSK (Quadrature Phase Shift Keying) modulation method. The station side device 1 also communicates with the user terminal device 2B using a 16QAM (16 Quadrature Amplitude Modulation) modulation method. The station side device 1 also communicates with the user terminal device 2C using a 64QAM (64 Quadrature Amplitude Modulation) modulation method. The station side device 1 may also communicate with other user terminal devices 2 simultaneously. Moreover, the station side device 1 may use still another method to communicate with the user terminal devices 2. The modulation method with each user terminal device 2 may be determined based on, for example, the communication capacity requirements of each user. Details of the signal processing method executed by the station side device 1 will be described below.

[0025] The signal acquisition unit 101 acquires a signal transmitted from the user terminal device (2A, 2B, 2C, etc.). The signal is, for example, an optical signal. The signal may be an electrical signal, etc. The signal acquisition unit 101 passes the acquired signal to the method identification unit 102.

[0026] The scheme identification unit 102 infers and identifies the scheme of the received signal. The scheme here refers to the modulation scheme, frame format, and encoding scheme. In other words, the scheme identification unit 102 identifies at least one of the modulation scheme, frame format, and encoding scheme based on the characteristics of the received signal.

[0027] The DSP demodulation unit 106 processes the signal acquired by the signal acquisition unit 101. More specifically, the DSP demodulation unit 106 demodulates the signal. The DSP demodulation unit 106 also detects frames included in the signal.

[0028] The decoding unit 107 performs a decoding process on the frames detected by the DSP demodulation unit 106 described above.

[0029] The DSP demodulation unit 106 and the decoding unit 107 may be collectively called the "signal processing unit." In other words, the signal processing unit processes the signal received by the station side device 1. The operation of the signal processing unit is controlled by the orchestrator 108 described below.

[0030] The orchestrator 108 controls the operation of signal processing functions according to at least one of the results of identification by the method identification unit 102 of the modulation method, frame format, and encoding method. The signal processing functions here are functions for processing such as demodulation, frame detection, and decoding in the above-mentioned DSP demodulation unit 106 and decoding unit 107. The signal processing functions have variations according to the method identification results. The orchestrator 108 is also called a "function control unit."

[0031] The orchestrator 108 activates signal processing functions (demodulation, frame detection, and decoding functions) according to the result of the identification by the format identification unit 102, and allocates resources for the signal processing functions to operate. The resources may include memory and a computing device.

[0032] The scheme identification unit 102 identifies the modulation scheme of the received signal based on, for example, a frequency distribution of the amplitude of the received signal. The scheme identification unit 102 also identifies the frame format of the received signal based on, for example, a bit string pattern of a preamble included in the received signal. The scheme identification unit 102 also performs a process of demodulating a code included in a frame detected from the received signal, and identifies the coding scheme of the received signal based on the amount of errors generated by the demodulation process.

[0033] The orchestrator 108 controls to operate a demodulation function corresponding to the modulation method identified by the method identification unit 102. The orchestrator 108 also controls to operate a frame detection function corresponding to the frame format identified by the method identification unit 102. The orchestrator 108 also controls to operate a decoding function corresponding to the encoding method identified by the method identification unit 102.

[0034] The station side device 1 of this embodiment configured with the above-mentioned functions receives a signal. The method identification unit 102 infers and identifies the modulation method, frame format, and coding method based on the received signal. The DSP demodulation unit 106 demodulates the received signal and detects frames based on the above-mentioned identification result. Furthermore, the decoding unit 107 performs decoding processing based on the identified coding method.

[0035] The parameters used by the scheme identification unit 102 when identifying the modulation scheme, frame format, and coding scheme are obtained by learning using the received signal. The scheme identification unit 102 stores the parameters. In addition, a parameter change unit (not shown) can rewrite the stored parameters as appropriate. In other words, for example, the station side device 1 can perform additional learning based on a signal received while in operation, and update the parameters.

[0036] When identifying the frame format, the format identification unit 102 compares, for example, the bit string pattern of the preamble of the received frame with a predetermined pattern, thereby making it possible to identify the frame format.

[0037] In addition, the method identification unit 102 actually performs a decoding process based on the detected frames, and identifies the coding method based on the error rate that occurs during the decoding process. When performing a decoding process for multiple coding methods, the error rate is extremely small when decoding is performed according to the coding method actually used, compared to other cases. This makes it possible to identify the coding method.

[0038] The method identification unit 102 identifies the modulation method and frame format based on the characteristics of the physical signal captured by the signal capture unit 101. The orchestrator 108 receives information on the identification result from the method identification unit 102. Based on the received identification result, the orchestrator 108 operates signal processing functions (demodulation function, frame detection function, decoding function) that match the identification result. In other words, the orchestrator 108 controls to change the signal processing function by specifying the method and processing data mode based on the received identification result.

[0039] As a process prior to modulation method identification, the station building device 1 quantizes the amplitude of the received signal calculated by polarization separation processing in multiple threads. The station building device 1 adds the occurrence frequency (histogram information) to the bins of the quantized amplitude while performing exclusive control among the multiple threads. The station building device 1 also creates amplitude histograms for the X polarization and the Y polarization by finally normalizing the histogram information. This amplitude histogram represents the characteristics of the modulation method. In other words, the method identification unit 102 identifies the modulation method based on this amplitude histogram. Details of the pre-processing described here will be described later in the seventh embodiment.

[0040] In order to identify the modulation scheme, the central office side device 1 may hold learning data corresponding to a plurality of OSNRs (Optical Signal to Noise Ratios) for each modulation scheme. Based on this learning data, the central office side device 1 performs nearest neighbor search between the received data and the learning data, and sets the nearest modulation scheme as the identification result of the modulation scheme. The learning data will be described later in the eighth embodiment.

[0041] According to this embodiment, it becomes possible to implement various transmission functions in one common station side device 1 (transmission device). In other words, it becomes possible to share one transmission device among various transmission services.

[0042] In addition, the station side device 1 (transmission device) of this embodiment does not need to exchange a special frame format with the communication partner when switching the transmission function. In other words, the station side device 1 (transmission device) does not need to transmit and receive a special sequence with the communication partner device for negotiation or the like when switching the transmission function.

[0043] Moreover, the central office device 1 (transmission device) of this embodiment makes it possible to identify the modulation method and frame method with low calculations. Moreover, it becomes possible to perform such identification in real time. Moreover, these transmission devices can realize identification processing that is compliant with noise in the communication path while keeping the calculations low.

[0044] 2 is a block diagram showing a schematic device configuration of a communication system configured using the station side device 1 of this embodiment. As shown in the figure, for example, a communication system 8 includes a plurality of station side devices (transmission devices) 1, a plurality of user terminal devices 2, an upper level device 3, and a management device 4.

[0045] The station side equipment (transmission equipment) 1 is equipment installed in the station of a telecommunications carrier. The station side equipment 1 is connected to one or more user terminal devices. It is also connected to other station side equipment 1. The station side equipment 1 is also connected to a higher-level equipment 3 on the higher-level network side.

[0046] The user terminal device 2 is a terminal device on the user side. When receiving communication services, the user terminal device 2 communicates with the station building equipment 1. In other words, the user terminal device 2 transmits signals that have been coded, framed, and modulated in a predetermined manner to the station building equipment 1. Conversely, the user terminal device 2 receives signals from the station building equipment 1.

[0047] The upper side device 3 is a device that belongs to a higher-level network of a telecommunications carrier, or a device that allows the station side device 1 to access the higher-level network. The upper side device 3 is connected to the station side device 1. The upper side device 3 is also connected to other devices (not shown) on the higher-level network side.

[0048] The management device 4 is a device having a function for managing communications between the station building equipment 1 and the user terminal device 2. The management device 4 passes parameters required for identifying the modulation method and the coding method to the station building equipment 1. Furthermore, when the modulation method and the coding method are identified on the user terminal device 2 side, the management device 4 passes parameters required for identifying these methods to the user terminal device 2.

[0049] [Second embodiment] Next, the second embodiment will be described. The second embodiment has a configuration based on a specific example (variation) for identifying the modulation method, the frame, and the decoding method in the configuration of the first embodiment. Note that the description of the matters already described in the previous embodiment may be omitted below. Here, the description will be centered on matters unique to this embodiment.

[0050] 3 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 11 includes an MC interface 1121, a PON interface 1122, an ADC interface 1123, a signal acquisition unit 1101, a method identification unit 1102, a parameter change unit 1109, a QPSK demodulation unit 1161a, a 16QAM demodulation unit 1161b, a DP-QPSK demodulation unit 1161c, an Ethernet frame detection unit 1162a, a video frame detection unit 1162b, a PON frame detection unit 1162c, an RS decoding unit 1163a, and an LDPC decoding unit 1163b.

[0051] The MC interface 1121, the PON interface 1122, and the ADC interface 1123 are each an interface for receiving a signal from the user terminal device 2. The MC interface 1121 is an interface for a media converter. The PON interface 1122 is an interface for a passive optical network (PON). The ADC interface 1123 is an interface using an analog-to-digital converter (ADC). Note that the station side device 1 may further have other types of interfaces.

[0052] The signal acquisition unit 1101 has a function of acquiring a signal received via an interface such as an MC interface 1121, a PON interface 1122, or an ADC interface 1123. The signal acquisition unit 1101 passes the received signal to a method identification unit 1102.

[0053] The method identification unit 1102 infers the format of the signal received via each interface. Specifically, the method identification unit 1102 infers the modulation method, frame format, and encoding method. The method identification unit 1102 notifies the orchestrator (see FIG. 1 of the first embodiment) of information on these inference results (identification results). This allows the orchestrator to operate a function that matches the identification result by the method identification unit 1102. Note that a more detailed functional configuration of the method identification unit 1102 is as shown in the figure, and will be described later.

[0054] The parameter change unit 1109 has a function of changing parameters used by the scheme identification unit 1102 to identify the modulation scheme, frame format, and encoding scheme. The parameter change unit 1109 rewrites the parameters stored in the scheme identification unit 1102 based on an instruction to change the parameters from the management device 4 described in the first embodiment (see FIG. 2). As an example, the parameter change unit 1109 can change the parameters when there is a change in the variation of the received signal.

[0055] The QPSK demodulation unit 1161a, the 16QAM demodulation unit 1161b, and the DP-QPSK demodulation unit 1161c demodulate signals modulated by the modulation methods of QPSK, 16QAM, and DP-QPSK (Dual Polarization Differential Quadrature Phase Shift Keying, dual polarization QPSK), respectively. The station side device (transmission device) 11 may further have a demodulation function corresponding to a modulation method other than these. Information on the modulation method identified by the method identification unit 1102 based on the input signal is passed to the orchestrator (see FIG. 1 of the first embodiment). The orchestrator appropriately selects and activates a demodulation function suitable for the identified modulation method. In other words, when activated by the orchestrator, each of the QPSK demodulation unit 1161a, the 16QAM demodulation unit 1161b, and the DP-QPSK demodulation unit 1161c demodulates the input signal of the respective method.

[0056] The Ethernet frame detection unit 1162a, the video frame detection unit 1162b, and the PON frame detection unit 1162c respectively detect an Ethernet frame, a video frame, and a PON frame from the demodulated received signal. The station side device (transmission device) 11 may further have a function for detecting frames of other formats. Information on the frame format identified by the format identification unit 1102 based on the input signal is passed to the orchestrator (see FIG. 1). The orchestrator appropriately selects and starts a frame detection function that matches the identified frame format. In other words, when the Ethernet frame detection unit 1162a, the video frame detection unit 1162b, and the PON frame detection unit 1162c are started by the orchestrator, they each detect frames of their respective formats.

[0057] The RS decoder 1163a and the LDPC decoder 1163b decode information coded with the RS code and the LDPC code, respectively. The LDPC code is an abbreviation for Low-Density Parity Check code. The RS code is an abbreviation for Reed-Solomon code. The station side device (transmission device) 11 may further have a function for decoding information coded with coding methods other than these. Information on the coding method identified by the method identification unit 1102 based on the input signal is passed to the orchestrator (see FIG. 1). The orchestrator appropriately selects and starts a decoding function suitable for the identified coding method. That is, when the RS decoder 1163a and the LDPC decoder 1163b are started by the orchestrator, they each perform a decoding process according to the respective method.

[0058] Here, we will explain the detailed functional configuration of the formula identification unit 1102. As shown in Fig. 3, the formula identification unit 1102 includes a preprocessing unit 1131, an inference unit 1132, and a parameter storage unit 1133. The functions of each unit are as follows.

[0059] The preprocessing unit 1131 performs preprocessing of information to be input to the scheme identification unit 1102. Specifically, the preprocessing unit 1131 outputs data suitable for processing by the inference unit 1132 by shaping the input signal (data).

[0060] The inference unit 1132 infers the modulation method, frame format, and encoding method based on the data passed from the preprocessing unit 1131. The inference unit 1132 outputs identification information of the modulation method, frame format, and encoding method as inference results. The inference unit 1132 notifies the orchestrator (see FIG. 1) of the identification information of the modulation method, frame format, and encoding method. When inferring the modulation method, frame format, and encoding method, the inference unit 1132 reads out the values ​​of necessary parameters from the parameter storage unit 1133 and uses them.

[0061] The parameter storage unit 1133 stores parameters necessary for the inference process performed by the inference unit 1132. These parameters may be rewritten by the parameter change unit 1109.

[0062] That is, the station side device (transmission device) 11 of this embodiment has the above-mentioned functional configuration. As a result, the station side device (transmission device) 11 acquires signals via various interfaces such as MC, PON, ADC, etc. The signal acquisition unit 1101 passes the acquired signal to the method identification unit 1102.

[0063] [Third embodiment] Next, a third embodiment will be described. The third embodiment has a configuration based on a specific example (variation) for identifying the modulation method, the frame, and the decoding method in the configuration of the first embodiment. Note that the description of the matters already described in the previous embodiments may be omitted below. Here, the description will be centered on matters unique to this embodiment.

[0064] 4 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 12 includes an MC interface 1221, a PON interface 1222, an ADC interface 1223, a signal acquisition unit 1201, a modulation method identification unit 1203, a QPSK demodulation unit 1261a, a 16QAM demodulation unit 1261b, a DP-QPSK demodulation unit 1261c, a frame identification unit 1204, an Ethernet frame detection unit 1262a, a video frame detection unit 1262b, a PON frame detection unit 1262c, an encoding identification unit 1205, an RS decoding unit 1263a, an LDPC decoding unit 1263b, and a parameter change unit 1209.

[0065] The modulation method identification unit 1203, the frame identification unit 1204, and the coding identification unit 1205 may be collectively referred to as a "method identification unit". The QPSK demodulation unit 1261a, the 16QAM demodulation unit 1261b, the DP-QPSK demodulation unit 1261c, and the like may be collectively referred to as a "demodulation unit". The Ethernet frame detection unit 1262a, the video frame detection unit 1262b, the PON frame detection unit 1262c, and the like may be collectively referred to as a "frame detection unit". The RS decoding unit 1263a, the LDPC decoding unit 1263b, and the like may be collectively referred to as a "decoding unit". The demodulation unit, the frame detection unit, and the decoding unit may be collectively referred to as a "signal processing unit". These names may be the same in other embodiments.

[0066] The feature of this embodiment is that the station office device 12 includes a modulation method 1203, a frame identification unit 1204, and an encoding identification unit 1205. That is, the station office device 12 of this embodiment includes a function unit that estimates each of the modulation method, the frame format, and the encoding method.

[0067] The modulation scheme identification unit 1203 infers the modulation scheme for the signal received via the ADC interface 1223. The modulation scheme identification unit 1203 notifies an orchestrator (not shown) of the modulation scheme (e.g., QPSK, 16QAM, DP-QPSK, etc.) resulting from the identification.

[0068] The frame identification unit 1204 infers the frame format of the received signal. Specifically, for a signal received via the ADC interface 1223, the frame identification unit 1204 receives the demodulated signal and infers the frame format. Furthermore, for a received on-off modulated signal (a signal received via the MC interface 1221, the PON interface 1222, etc.), the frame identification unit 1204 receives the signal directly from the signal capture unit 1201 and infers the frame format. The frame identification unit 1204 notifies an orchestrator (not shown) of the frame format (for example, an Ethernet frame, a video frame, a PON frame, etc.) of the identification result.

[0069] The coding identification unit 1205 infers the coding method for the frame detected from the received signal. The coding identification unit 1205 notifies an orchestrator (not shown) of the coding method (RS, LDPC, etc.) of the identification result.

[0070] The internal functional configurations of the modulation scheme identifying unit 1203, the frame identifying unit 1204, and the encoding identifying unit 1205 will be described later with reference to FIG.

[0071] The central office device 12 receives signals via interfaces such as the MC interface 1221, the PON interface 1222, and the ADC interface 1223. Then, for the signal received at the ADC interface 1223, the modulation method identification unit 1203 infers the modulation method. When the modulation method identification unit 1203 reports the modulation method identification result to the orchestrator, the orchestrator selects and operates a demodulation function suited to that modulation method. The demodulation function selected here is one of the QPSK demodulation unit 1261a, the 16QAM demodulation unit 1261b, the DP-QPSK demodulation unit 1261c, and the like.

[0072] The frame identification unit 1204 identifies the frame format of a signal that has been demodulated by any of the demodulation units, or a signal (OOK signal) received by an interface other than the ADC interface 1223 (such as the MC interface 1221 or the PON interface 1222). Note that "OOK" is an abbreviation for "on-off-keying." When the frame identification unit 1204 reports the frame format identification result to the orchestrator, the orchestrator selects and operates a frame detection function that matches the frame format. The frame detection function selected here is one of the Ethernet frame detection unit 1262a, video frame detection unit 1262b, PON frame detection unit 1262c, etc.

[0073] After frame detection, the signal is input to the encoding identification unit 1205. The encoding identification unit 1205 infers the encoding method. When the encoding identification unit 1205 reports the encoding format identification result to the orchestrator, the orchestrator selects and operates a decoding function that matches the encoding format. The decoding function selected here is either the RS decoding unit 1263a, the LDPC decoding unit 1263b, etc. In this way, the station side device 12 demodulates and decodes the received signal.

[0074] The MC interface 1221, the PON interface 1222, and the ADC interface 1223 are similar to the MC interface 1121, the PON interface 1122, and the ADC interface 123 already described in the second embodiment, respectively. Note that the station side device 12 may be provided with communication interfaces other than these.

[0075] The signal acquisition unit 1201 is similar to the signal acquisition unit 1101 already described in the second embodiment. Note that the signal acquisition unit 1201 of this embodiment passes a signal received via an ADC interface 1223 to a modulation method identification unit 1203. Furthermore, the signal acquisition unit 1201 passes a signal (OOK signal) received via an MC interface 1221 or a PON interface 1222, etc., directly to a frame identification unit 1204 without passing it to the modulation method identification unit 1203.

[0076] In other words, the signal acquisition unit 1201 passes to the modulation scheme identification unit 1203 only the signal received at the interface that is based on a modulation scheme in which a constellation point is provided by shifting the phase.

[0077] The QPSK demodulation unit 1261a, the 16QAM demodulation unit 1261b, and the DP-QPSK demodulation unit 1261c demodulate the received signals modulated by QPSK, 16QAM, and DP-QPSK, respectively, as already described in the second embodiment. Note that the station building device 12 may further include a function for demodulating signals modulated by other methods.

[0078] The Ethernet frame detector 1262a, the video frame detector 1262b, and the PON frame detector 1262c respectively detect an Ethernet frame, a video frame, and a PON frame, as already described in the second embodiment. The station building device 12 may further include a function for detecting frames of other formats.

[0079] The RS decoder 1263a and the LDPC decoder 1263b decode the RS code and the LDPC code, respectively, as already described in the second embodiment. Note that the station side device 12 may further include a function for decoding a code encoded by another method.

[0080] The parameter modification unit 1209 modifies the parameters stored internally in the modulation scheme identification unit 1203, the frame identification unit 1204, and the encoding identification unit 1205, just as the parameter modification unit 1109 in the second embodiment modifies the parameters stored internally in the scheme identification unit 1102 (see also FIG. 5).

[0081] 5 is a schematic functional block diagram showing the internal functional configuration of each of the modulation scheme identification unit 1203, the frame identification unit 1204, and the coding identification unit 1205 described in FIG. 4 above. As shown in the figure, the modulation scheme identification unit 1203 is configured to include a preprocessing unit 1231, an inference unit 1232, and a parameter storage unit 1233. Moreover, the frame identification unit 1204 is configured to include a preprocessing unit 1241, an inference unit 1242, and a parameter storage unit 1243. Moreover, the coding identification unit 1205 is configured to include a preprocessing unit 1251, an inference unit 1252, and a parameter storage unit 1253.

[0082] In the modulation scheme identification unit 1203, a preprocessing unit 1231 performs preprocessing of information input to an inference unit 1232. Specifically, the preprocessing unit 1231 outputs data suitable for processing by the inference unit 1232 by shaping the input signal (data).

[0083] In the modulation scheme identification unit 1203, the inference unit 1232 infers (identifies) the modulation scheme based on the data passed from the preprocessing unit 1231. The inference unit 1232 outputs identification information of the modulation scheme as an inference result. The inference unit 1232 notifies the orchestrator of this identification information of the modulation scheme. Note that when inferring the modulation scheme, the inference unit 1232 reads out necessary parameter values ​​from the parameter storage unit 1233 and uses them.

[0084] In the modulation scheme identification unit 1203, a parameter storage unit 1233 stores parameters necessary for the processing of inferring the modulation scheme by the inference unit 1232. A parameter change unit 1209 can rewrite the parameters stored in the parameter storage unit 1233.

[0085] In the frame identification unit 1204, a preprocessing unit 1241 preprocesses information to be input to the inference unit 1242. Specifically, the preprocessing unit 1241 outputs data suitable for processing by the inference unit 1242 by shaping the input signal (data).

[0086] In the frame identification unit 1204, the inference unit 1242 infers (identifies) the frame format based on the data passed from the preprocessing unit 1241. The inference unit 1242 outputs frame format identification information as an inference result. The inference unit 1242 notifies the orchestrator of this frame format identification information. When inferring the frame format, the inference unit 1242 reads out necessary parameter values ​​from the parameter storage unit 1243 and uses them.

[0087] In the frame identification unit 1204, a parameter storage unit 1243 stores parameters necessary for the process of inferring the frame format by the inference unit 1242. A parameter change unit 1209 can rewrite the parameters stored in the parameter storage unit 1243.

[0088] In the encoding identification unit 1205, a preprocessing unit 1251 performs preprocessing of information to be input to an inference unit 1252. Specifically, the preprocessing unit 1251 outputs data suitable for processing by the inference unit 1252 by shaping the input signal (data).

[0089] In the encoding identification unit 1205, the inference unit 1252 infers (identifies) the encoding method based on the data passed from the preprocessing unit 1251. The inference unit 1252 outputs the identification information of the encoding method as an inference result. The inference unit 1252 notifies the orchestrator of this identification information of the encoding method. Note that when inferring the encoding method, the inference unit 1252 reads out the values ​​of necessary parameters from the parameter storage unit 1253 and uses them.

[0090] In the encoding identification unit 1205, a parameter storage unit 1253 stores parameters necessary for the processing of inferring the encoding method by the inference unit 1242. A parameter change unit 1209 can rewrite the parameters stored in the parameter storage unit 1253.

[0091] In this manner, with the configuration shown in FIG. 5, the modulation method identification unit 1203 identifies the modulation method and reports the information of the identification result to the orchestrator. This allows the orchestrator to operate a demodulation function suitable for the identification result. Also, the frame identification unit 1204 identifies the frame format and reports the information of the identification result to the orchestrator. This allows the orchestrator to operate a frame detection function suitable for the identification result. Also, the encoding identification unit 1205 identifies the encoding method and reports the information of the identification result to the orchestrator. This allows the orchestrator to operate a decoding function suitable for the identification result.

[0092] [Fourth embodiment] Next, the fourth embodiment will be described. The fourth embodiment has a configuration based on a specific example (variation) for identifying the modulation method, the frame, and the decoding method in the configuration of the first embodiment. Note that the description of the matters already described in the previous embodiments may be omitted below. Here, the description will be centered on matters unique to this embodiment.

[0093] 6 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 13 includes an MC interface 1321, a PON interface 1322, an ADC interface 1323, a signal acquisition unit 1301, a modulation method identification unit 1303, a QPSK demodulation unit 1361a, a 16QAM demodulation unit 1361b, a DP-QPSK demodulation unit 1361c, a frame identification unit 1304, an Ethernet frame detection unit 1362a, a video frame detection unit 1362b, a PON frame detection unit 1362c, an encoding identification unit 1305, an RS decoding unit 1363a, an LDPC decoding unit 1363b, and a parameter change unit 1309.

[0094] One of the features of the station building device 13 of this embodiment is how the frame identification unit 1304 is implemented. Another feature of the station building device 13 is how the encoding identification unit 1305 is implemented. These will be described below with reference to Figs. 6 and 7, respectively. Note that only either the frame identification unit 1304 or the encoding identification unit 1305 of this embodiment may be implemented. When only the frame identification unit 1304 is implemented, the configuration described in the other embodiments may be used as the function for identifying the encoding method. When only the encoding identification unit 1305 is implemented, the configuration described in the other embodiments may be used as the function for identifying the frame format.

[0095] 7 is a block diagram showing a schematic functional configuration of a frame classifier according to this embodiment. As shown in the figure, the frame classifier 1304 includes a classifier 1341 that performs classifier processing by comparing bit strings of a preamble, and a parameter storage unit 1343.

[0096] The identification processing unit 1341 of this embodiment identifies the frame format by comparing the bit strings of the preamble. Specifically, the identification processing unit 1341 compares the preamble of the received signal with the preambles of frames of each format stored in advance. Specifically, the identification processing unit 1341 compares the preamble of the received signal with the preambles of Ethernet frames, video frames, PON frames, etc. (other formats of frames are also possible). The identification processing unit 1341 identifies the matching type of frame as the frame format of the actual received signal. When using such a method of the identification processing unit 1341, the amount of calculation is greater than in the method of the second or third embodiment, but more accurate frame format identification is possible.

[0097] The parameter storage unit 1343 stores parameters to be referred to when the above-mentioned identification processing unit 1341 performs the identification process. The parameter storage unit 1343 may store bit string patterns of preambles in various frame formats. The data stored in the parameter storage unit 1343 may be rewritten by the parameter change unit 1309.

[0098] With the above configuration, the frame identification unit 1304 identifies the frame format of a received signal based on the bit string pattern of the preamble contained in the received signal.

[0099] 8 is a block diagram showing a schematic functional configuration of the encoding identification unit according to this embodiment. As shown in the figure, the encoding identification unit 1305 includes an identification processing unit 1351 by decoding and a parameter storage unit 1353.

[0100] The identification processing unit 1351 of this embodiment identifies the coding method by actually performing decoding processing by a plurality of methods. The identification processing unit 1351 performs different decoding processing such as RS decoding and LDPC decoding (which may further include decoding by other methods) with a fixed code length, for example. The identification processing unit 1351 identifies the coding method with the smallest number of errors in the received signal obtained by these decoding processes as the coding method of the actually received signal. The identification processing unit 1351 may also identify the coding method of the actually received signal by performing error correction processing during decoding and determining the redundancy that allows error correction. When using such a method of the identification processing unit 1351, although the amount of calculation is larger than that in the method of the second or third embodiment, it is possible to more accurately identify the coding method.

[0101] The parameter storage unit 1353 stores parameters to be referenced during the identification process by the above-mentioned identification processing unit 1351. The data stored in the parameter storage unit 1353 may be rewritten by the parameter change unit 1309.

[0102] With the above configuration, the encoding identification unit 1305 performs a process of demodulating the code contained in the frame detected from the received signal, and identifies the encoding method of the received signal based on the amount of errors generated by the demodulation process.

[0103] As other functions (functions whose description is omitted in this embodiment) possessed by the station side device (transmission device) 13, it is possible to use functions similar to those described in the other embodiments.

[0104] [Fifth embodiment] Next, the fifth embodiment will be described. The fifth embodiment has a configuration based on a specific example (variation) for identifying the modulation method, the frame, and the decoding method in the configuration of the first embodiment. Note that the description of the matters already described in the previous embodiments may be omitted below. Here, the description will be centered on matters unique to this embodiment.

[0105] 9 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 14 includes an MC interface 1421, a PON interface 1422, an ADC interface 1423, a signal acquisition unit 1401, a modulation method identification unit 1403, a QPSK demodulation unit 1461a, a 16QAM demodulation unit 1461b, a DP-QPSK demodulation unit 1461c, a frame identification unit 1404, an Ethernet frame detection unit 1462a, a video frame detection unit 1462b, a PON frame detection unit 1462c, an encoding determination unit 1405, an RS decoding unit 1463a, an LDPC decoding unit 1463b, a parameter change unit 1409, and an encoding method storage unit 1471.

[0106] The station building device 14 according to this embodiment is characterized by the encoding decision unit 1405 and the encoding method storage unit 1471. In this embodiment, the station building device 14 performs processing after detecting a frame based on the frame type, user identification information, user attribute information, etc. More specifically, the processing is as follows.

[0107] The encoding method storage unit 1471 stores the relationship between the information acquired by the station side device 14 in the process up to frame detection and the encoding method. Specifically, the encoding method storage unit 1471 stores, for example, the correspondence relationship between the frame format and the encoding method. Alternatively, the encoding method storage unit 1471 stores, for example, the correspondence relationship between the user identification information (ID) that can be acquired from the detected frame and the encoding method. Alternatively, the encoding method storage unit 1471 may store, for example, the correspondence relationship between the user attribute (identification information of the group to which the user belongs, etc.) specified by the above-mentioned user identification information and the encoding method. Alternatively, the encoding method storage unit 1471 may store, for example, the correspondence relationship between the information on the type of the user terminal device 2 that can be acquired from the detected frame and the encoding method.

[0108] The encoding determination unit 1405 determines the encoding method by referring to the encoding method storage unit 1471 based on information obtainable from the detected frame. For example, the encoding determination unit 1405 obtains the type of the frame identified by the frame identification unit 1404 (frame format identification information), and reads out the encoding method corresponding to the type from the encoding method storage unit 1471. Alternatively, the encoding determination unit 1405 reads out user identification information embedded in, for example, a preamble portion in the detected frame. Then, the encoding determination unit 1405 reads out the encoding method corresponding to the user identification information from the encoding method storage unit 1471. Alternatively, the encoding determination unit 1405 determines attribute information of the user based on the read out user identification information. Then, the encoding determination unit 1405 reads out the encoding method corresponding to the user attribute from the encoding method storage unit 1471. Alternatively, the encoding determination unit 1405 reads out information on the type of the user terminal device embedded in, for example, a preamble portion in the detected frame. Then, the encoding determination unit 1405 reads out the encoding method corresponding to the user terminal device type information from the encoding method storage unit 1471 .

[0109] 10, 11, 12, and 13 are schematic diagrams showing examples of the configuration of data stored in the encoding method storage unit 1471. As shown in the figures, the encoding method storage unit 1471 stores, as table-format data, a correspondence relationship between the information that the station side device 14 can acquire by processing up to frame detection and the encoding method identification information. In the example of FIG. 10, the encoding method storage unit 1471 stores a correspondence relationship between the frame format identification information and the encoding method identification information. In the example of FIG. 11, the encoding method storage unit 1471 stores a correspondence relationship between the user identification information and the encoding method identification information. In the example of FIG. 12, the encoding method storage unit 1471 stores a correspondence relationship between the user attribute information and the encoding method identification information. In the example of FIG. 13, the encoding method storage unit 1471 stores a correspondence relationship between the user terminal device type information and the encoding method identification information.

[0110] The encoding method storage unit 1471 may store the correspondence between the encoding method identification information and information other than the above (however, information that the station side device 14 can obtain up to the processing at the frame detection stage). In that case, the encoding decision unit 1405 refers to the table held by the encoding method storage unit 1471 based on the obtained information, and reads out the encoding method identification information.

[0111] The coding determination unit 1405 determines the coding method by any of the above methods. As a result, the station side device 14 can perform a decoding process according to the coding method obtained as a result of the determination.

[0112] [Sixth embodiment] Next, a sixth embodiment will be described. In the sixth embodiment, the station side device includes an orchestrator. Note that the following description may omit the matters already described in the previous embodiments. Here, the description will be centered on matters unique to this embodiment.

[0113] 14 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 15 includes an MC interface 1521, a PON interface 1522, an ADC interface 1523, a signal acquisition unit 1501, a modulation method identification unit 1503, a QPSK demodulation unit 1561a, a 16QAM demodulation unit 1561b, a DP-QPSK demodulation unit 1561c, a frame identification unit 1504, an Ethernet frame detection unit 1562a, a video frame detection unit 1562b, a PON frame detection unit 1562c, an encoding identification unit 1505, an RS decoding unit 1563a, an LDPC decoding unit 1563b, a parameter change unit 1509, and an orchestrator 1572.

[0114] The orchestrator 1572, which is a feature of this embodiment, corresponds to the orchestrator 108 described in Fig. 1. The orchestrator 1572 is also called a "function control unit." The orchestrator 1572 manages and controls the switching of functions within the station side device 15 according to the identification results of the modulation method, frame format, and encoding method.

[0115] Specifically, the orchestrator 1572 controls the operation of functions according to the identification results of the modulation method, frame format, and encoding method. In other words, the orchestrator 1572 activates functions required according to the identification results, and allocates resources (computational resources) required for the operation of those functions.

[0116] That is, the orchestrator 1572 receives a report on the identification result of the modulation method from the modulation method identification unit 1503. The orchestrator 1572 appropriately operates one of the QPSK demodulation unit 1561a, the 16QAM demodulation unit 1561b, the DP-QPSK demodulation unit 1561, etc. (which may be a function other than those exemplified here) according to the identification result of the modulation method, and allocates resources for that purpose. The orchestrator 1572 also receives a report on the identification result of the frame format from the frame identification unit 1504. The orchestrator 1572 appropriately operates one of the Ethernet frame detection unit 1562a, the video frame detection unit 1562b, the PON frame detection unit 1562c, etc. (which may be a function other than those exemplified here) according to the identification result of the frame format, and allocates resources for that purpose. The orchestrator 1572 also receives a report on the identification result of the encoding method from the encoding identification unit 1505. Depending on the result of the encoding method identification, the orchestrator 1572 appropriately operates one of the RS decoding unit 1563a, the LDPC decoding unit 1563b, etc. (which may have functions other than those illustrated here), and allocates resources for that purpose.

[0117] In order for the orchestrator 1572 to control the above functions, the modulation scheme identification unit 1503 notifies the orchestrator 1572 of information on the result of its own identification of the modulation scheme. Also, the frame identification unit 1504 notifies the orchestrator 1572 of information on the result of its own identification of the frame format. Also, the encoding identification unit 1505 notifies the orchestrator 1572 of information on the result of its own identification of the encoding scheme.

[0118] An example of the operation of the orchestrator is as follows: For example, if an inference unit inside the modulation scheme identification unit 1503 determines that the received signal is a signal modulated by the QPSK scheme, it reports the identification result to the orchestrator 1572. The orchestrator 1572 activates the function of the QPSK demodulation unit 1561a for demodulating the reported QPSK signal. The orchestrator 1572 also secures memory necessary for the QPSK demodulation unit 1561a to function. The orchestrator 1572 then notifies the QPSK demodulation unit 1561a (its inference unit, etc.) of the address of that memory, and directs the signal to be processed to the QPSK demodulation unit 1561a. The same applies to the demodulation units of other systems. The same also applies to each frame detection unit. The same also applies to each decoding unit.

[0119] The orchestrator 1572 of this embodiment operates functions corresponding to the identification results of the modulation method, frame format, and encoding method as described above.

[0120] [Seventh embodiment] Next, a seventh embodiment will be described. The seventh embodiment shows an example of a more detailed configuration for identifying the modulation method in particular. The configuration of this embodiment is an example of a configuration that enables the processing of identifying the modulation method to be executed in real time. Note that, in the following, the description of the matters already described in the previous embodiments may be omitted. Here, the description will be centered on matters unique to this embodiment.

[0121] Fig. 15 is a block diagram showing a schematic functional configuration of the station side device (transmission device) according to this embodiment. As shown in the figure, the station side device (transmission device) 16 includes an ADC interface 1623, a signal acquisition unit 1601, a clock synchronization unit 1681, a polarization separation and adaptive filter unit 1682, a modulation method identification unit 1603, a carrier phase recovery unit 1683, a symbol decision unit 1661, a frame detection unit 1662, and a decoding unit 1663. Note that Fig. 15 shows only the configuration when a signal is received by the ADC interface 1623, and omits the configuration for receiving a signal by an MC interface or a PON interface. Receiving a signal by an MC interface or a PON interface is as described in other embodiments.

[0122] The ADC interface 1623 is an interface for receiving signals by the ADC.

[0123] The signal acquisition unit 1601 acquires a received signal via the ADC interface 1623 .

[0124] The clock synchronizer 1681 synchronizes the received signal with a clock signal for processing in the station side device 16 .

[0125] The polarization separation and adaptive filter unit 1682 and the modulation scheme identification unit 1603 identify the modulation scheme of the received signal. The processing performed by the polarization separation and adaptive filter unit 1682 is preprocessing for identifying the modulation scheme. The configurations of the polarization separation and adaptive filter unit 1682 and the modulation scheme identification unit 1603 will be described in more detail later with reference to FIG. 16. As will be described later, the modulation scheme identification unit 1603 identifies the modulation scheme of the received signal based on the frequency distribution of the amplitude of the received signal.

[0126] Information on the processing data length, the multi-level value, and the presence or absence of polarization multiplexing is obtained as a result of processing by the modulation scheme identification unit 1603. The modulation scheme identification unit 1603 passes the information on the processing data length, the multi-level value, and the presence or absence of polarization multiplexing to the carrier phase recovery unit 1683, the symbol decision unit 1661, the frame detection unit 1662, and the decoding unit 1663.

[0127] The carrier phase recovery unit 1683 evaluates the frequency shift and phase shift to recover the input waveform of the received signal.

[0128] The symbol decision unit 1661 determines the symbols contained in the received signal based on the signal recovered by the carrier phase recovery unit 1683 .

[0129] The frame detection unit 1662 detects frames as described in other embodiments.

[0130] The decoding unit 1663 decodes the code contained in the detected frame, as described in the other embodiments.

[0131] 16 is a functional block diagram showing a more detailed functional configuration of the polarization splitting and adaptive filter unit 1682 and the modulation scheme identifying unit 1603 of this embodiment. As shown in the figure, this function includes a thread processing unit 1685, a polarization multiplicity identifying unit 1688, a shared memory 1684, a filter coefficient updating unit 1686, and a histogram adding unit 1687. This function performs processing in multithreads. As shown in the figure, the processing of identifying the modulation scheme is executed at a stage after the polarization splitting and adaptive filter.

[0132] The thread processing unit 1685 processes the input signal on a thread-by-thread basis, and includes an adaptive filter 16851, an amplitude histogram information generating unit 16852, a normalizing unit (X polarization) 16854, a normalizing unit (Y polarization) 16855, an identification unit (X polarization) 16856, and an identification unit (Y polarization) 16857. The station side device 16 has the configuration of this thread processing unit 1685 for each thread. The amplitude histogram information generating unit 16852 includes a quantizing unit 16853.

[0133] The shared memory 1684 stores information necessary for the processing of the function. Specifically, the shared memory 1684 includes a filter coefficient storage unit 16841 and an amplitude histogram storage unit 16842.

[0134] The filter coefficient storage unit 16841 stores the filter coefficient of the adaptive filter 16851. As will be described later, the adaptive filter 16851 stores the filter coefficient P xx , P xy , P yx , P yy The filter coefficient storage unit 16841 stores these coefficients P xx , P xy , P yx , P yy The filter coefficient storage unit 16841 in the shared memory 1684 is updated by the filter coefficient update unit 1686.

[0135] The amplitude histogram storage unit 16842 stores information on the amplitude histogram for identifying the modulation method. The amplitude histogram for the X-polarized wave is h X The amplitude histogram for the Y polarization is h Y However, if the received signal is a one-way modulated signal, the amplitude histogram storage unit 16842 may store the amplitude histogram information only for that one-way polarized wave. X and h Y Each has frequency information for each bin. Xand h Y can be expressed as vector data, for example. The frequency of a bin is h X (bin) or h Y It is expressed as (bin), etc.

[0136] The adaptive filter 16851 is a filter having the configuration shown in Fig. 17. The adaptive filter 16851 has a filter coefficient P xx , P xy , P yx , P yy These filter coefficients are read out from the filter coefficient storage unit 16841.

[0137] The filter coefficient update unit 1686 updates the filter coefficients stored in the filter coefficient storage unit 16841 of the shared memory 1684. The filter coefficient update unit 1686 updates the filter coefficients based on data from a plurality of thread processing units 1685. The filter coefficient update unit 1686 updates the filter coefficients while performing exclusive control between the threads so as to prevent collisions in data updates between the threads.

[0138] The filter coefficient update unit 1686 updates the filter coefficients according to the following equation (1).

[0139]

number

[0140] The polarization multiplexing identifying unit 1688 determines whether or not polarization multiplexing is being performed based on the signal output from the adaptive filter 16851. The polarization multiplexing identifying unit 1688 passes information on the determination result to the amplitude histogram information generating unit 16852.

[0141] The amplitude histogram information generator 16852 generates amplitude histogram information for the received signal and passes it to the histogram adder 1687. If the signal is one in which both the X polarization and the Y polarization are modulated by information from the polarization multiplicity identifier 1688, the amplitude histogram information generator 16852 generates amplitude histogram information for each of the X polarization and the Y polarization. If the signal is one-way modulated, the amplitude histogram information generator 16852 generates amplitude histogram information only for that one-way polarization. The generation of histogram information by the amplitude histogram information generator 16852 is a preprocessing step for identifying the modulation method.

[0142] The amplitude histogram information generating unit 16852 includes a quantizing unit 16853. The quantizing unit 16853 quantizes the received signal amplitude in the polarization separation. The amplitude histogram information generating unit 16852 generates information for adding occurrence frequencies for bins determined as a result of quantization by the quantizing unit 16853 for each thread. The amplitude histogram information generating unit 16852 passes the generated histogram information to the histogram adding unit 1687.

[0143] The histogram addition unit 1687 sequentially adds the frequency of the detected amplitude to the amplitude histogram based on the information passed from the amplitude histogram information generation unit 16852. The histogram addition unit 1687 adds the histogram information based on data from a plurality of thread processing units 1685. The histogram addition unit 1687 updates the filter coefficients while performing mutual exclusion control between threads so as to prevent collisions in updating data between threads.

[0144] If the signal is polarization multiplexed, the histogram adder 1687 adds amplitude histogram information for each of the X polarization and the Y polarization based on the identification result by the polarization multiplexing identification unit 1688. If the signal is a unidirectional modulated signal, the histogram adder 1687 adds amplitude histogram information only for the unidirectional polarization.

[0145] The process of adding frequency information for each bin by the histogram adder 1687 is represented by the following equation (2) for the X polarization and by the following equation (3) for the Y polarization.

[0146]

number

number

[0147] A normalization unit (X polarization) 16854 reads out the histogram of the X polarization from the amplitude histogram storage unit 16842, and normalizes it.

[0148] A normalization unit (Y polarization) 16855 reads out the histogram of the X polarization from the amplitude histogram storage unit 16842 and normalizes it.

[0149] The identification unit (X polarization) 16856 identifies the modulation method of the X polarization based on the normalized histogram of the X polarization.

[0150] The identification unit (Y polarization) 16857 identifies the modulation method of the Y polarization based on the histogram of the normalized Y polarization.

[0151] When the received signal is a one-way modulated signal, only one of the discrimination unit (X polarization) 16856 and the discrimination unit (Y polarization) 16857 needs to discriminate the modulation method. Each of the discrimination unit (X polarization) 16856 and the discrimination unit (Y polarization) 16857 can use a method such as a CNN (Convolutional Neural Network), an approximate nearest neighbor search, a neighborhood search, or detection based on the number of extreme values ​​of a histogram in the discrimination process.

[0152] With the above-described configuration, the station side device 16 according to this embodiment can identify the modulation method in real time.

[0153] [Eighth embodiment] Next, an eighth embodiment will be described. The eighth embodiment shows an example of a more detailed configuration for identifying the modulation method in particular. The configuration of this embodiment is an example of a configuration that enables the processing of identifying the modulation method to be executed in real time. Note that, in the following, the description of the matters already described in the previous embodiments may be omitted. Here, the description will be centered on matters unique to this embodiment.

[0154] This embodiment is one embodiment of a method for implementing the discrimination unit (X polarization) 16856 and the discrimination unit (Y polarization) 16857 in the discrimination process of the modulation method described in the seventh embodiment.

[0155] 18 is a block diagram showing a functional configuration for identifying a modulation scheme included in the station side device according to this embodiment. As shown in the figure, the station side device 17 includes a shared memory 1784 and an identification unit 1785. The shared memory 1784 includes a learning data storage unit 17843. The discrimination unit 1785 includes an discrimination unit (X polarization) 17856 and an discrimination unit (Y polarization) 17857. Although illustration of other functional configurations of the station building device 17 is omitted, they may be similar to those described in the other embodiments.

[0156] In this embodiment, the learning data storage unit 17843 stores the following learning data. That is, the learning data is data obtained by learning a histogram from a signal having a plurality of OSNRs (Optical Signal to Noise Ratios) for each transmission format (modulation method). In the example shown in Fig. 18, the learning data storage unit 17843 stores learning data for OSNR = 20, 19, ... for each of the modulation methods of QPSK, 16QAM, and 64QAM. Note that the learning data storage unit 17843 may further store learning data for other modulation methods.

[0157] Each of the discrimination unit (X polarization) 17856 and the discrimination unit (Y polarization) 17857 performs nearest neighbor search processing using a histogram generated from the received signal and the histogram of the above-mentioned learning data. Each of the discrimination unit (X polarization) 17856 and the discrimination unit (Y polarization) 17857 sets the modulation scheme corresponding to the learning data that has the smallest distance between the histogram generated from the received signal as the discrimination result. Note that the discrimination method may be not only the nearest neighbor search exemplified here, but also an approximate nearest neighbor search or a discrimination algorithm of another method.

[0158] According to this embodiment, a process of identifying a modulation scheme is realized based on learning data.

[0159] Although a number of embodiments have been described above, any of the following modified examples may also be implemented.

[0160] [Variation 1] In the above embodiment, the transmission device is configured to include an orchestrator (function control unit). As a modified example, the orchestrator may be implemented as an independent device separate from the transmission device. In this case, the orchestrator (function control device) includes a function control unit. The function control unit receives information on the identification result of at least one of the modulation method, frame format, and encoding method identified by the transmission device based on the characteristics of the signal received by the transmission device, and controls the transmission device to operate a signal processing function according to the received identification result.

[0161] [Variation 2] In the above embodiment, the transmission device adaptively identifies the modulation method, frame format, and coding method, and operates a function according to the identification result. As a modified example, the transmission device may identify at least one of the modulation method, frame format, and coding method, and operate a function according to the identification result.

[0162] [Variation 3] In the above embodiment, the communication system 8 (see FIG. 2) includes a central office side device (transmission device) 1 and a user terminal device 2. The central office side device has a control function for identifying the modulation method, frame format, and encoding method based on the received signal, and for operating a function according to the identification result. Similarly, the user terminal device may have a control function for identifying the modulation method, frame format, and encoding method based on the received signal, and for operating a function according to the identification result.

[0163] According to any of the above-described embodiments (including the modified examples), the transmission device realizes a blind adaptive switching function of the receiving method in the software implementation of the function. Although such a transmission device is effective in realizing an optical access system, the above-described embodiments may be applied to communication systems other than the optical access system. [Industrial Applicability]

[0164] The present invention can be used, for example, to communicate information, although the scope of use of the present invention is not limited to the examples given herein. [Explanation of symbols]

[0165] 1...station side device (transmission device), 2, 2A, 2B, 2C...user terminal device, 3...upper side device, 4...management device, 8...communication system, 11, 12, 13, 14, 15, 16...station side device (transmission device), 101...signal acquisition unit, 102...system identification unit, 106...DSP demodulation unit, 107...decoding unit, 108...orchestrator (function control unit), 1101...signal acquisition unit, 1102...system identification unit, 1109...parameter change unit, 1121...MC interface, 1122...PON interface, 1123...ADC interface, 1131...preprocessing unit, 1 132... inference unit, 1133... parameter storage unit, 1161a... QPSK demodulation unit, 1161b... 16QAM demodulation unit, 1161c... DP-QPSK demodulation unit, 1162a... Ethernet frame detection unit, 1162b... video frame detection unit, 1162c... PON frame detection unit, 1163a... RS decoding unit, 1163b... LDPC decoding unit, 1201... signal acquisition unit, 1203... modulation method identification unit, 1203... modulation method identification unit, 1204... frame identification unit, 1205... encoding identification unit, 1209... parameter change unit, 1221... MC interface, 1222... PON interface, 1223...ADC interface, 1231...preprocessing unit, 1232...inference unit, 1233...parameter storage unit, 1241...preprocessing unit, 1242...inference unit, 1243...parameter storage unit, 1251...preprocessing unit, 1252...inference unit, 1253...parameter storage unit, 1261a...QPSK demodulation unit, 1261b...16QAM demodulation unit, 1261c...DP-QPSK demodulation unit, 1262a...Ether frame detection unit, 1262b...video frame detection unit, 1262c...PON frame detection unit, 1263a...RS decoding unit, 1263b...LDPC decoding unit, 1301...signal acquisition unit, 1303...modulation method identification unit, 1304...frame identification unit, 1305...encoding identification unit, 1309...parameter change unit, 1321...MC interface, 1322...PON interface, 1323...ADC interface, 1341...identification processing unit, 1343...parameter storage unit, 1351...identification processing unit, 1353...parameter storage unit, 1361a...QPSK demodulation unit, 1361b...16QAM demodulation unit, 1361c...DP-QPSK demodulation unit, 1362a...Ether frame detection unit, 1362b...video frame detection unit,1362c...PON frame detection unit, 1363a...RS decoding unit, 1363b...LDPC decoding unit, 1401...signal acquisition unit, 1403...modulation method identification unit, 1404...frame identification unit, 1405...encoding determination unit, 1409...parameter change unit, 1421...MC interface, 1422...PON interface, 1423...ADC interface, 1461a...QPSK demodulation unit, 1461b...16QAM demodulation unit, 1461c...DP-QPSK demodulation unit, 1462a...Ether frame detection unit, 1462b...video frame detection unit, 1462 c...PON frame detection unit, 1463a...RS decoding unit, 1463b...LDPC decoding unit, 1471...encoding method storage unit, 1501...signal acquisition unit, 1503...modulation method identification unit, 1504...frame identification unit, 1505...encoding identification unit, 1509...parameter change unit, 1521...MC interface, 1522...PON interface, 1523...ADC interface, 1561a...QPSK demodulation unit, 1561b...16QAM demodulation unit, 1561c...DP-QPSK demodulation unit, 1562a...Ether frame detection unit, 1562b...video frame detection unit, 1562c...PON frame detection unit, 1563a...RS decoding unit, 1563b...LDPC decoding unit, 1572...orchestrator (functional control unit), 1601...signal acquisition unit, 1603...modulation method identification unit, 1623...ADC interface, 1661...symbol decision unit, 1662...frame detection unit, 1663...decoding unit, 1681...clock synchronization unit, 1682...polarization separation and adaptive filter unit, 1683...carrier phase recovery unit, 1684...shared memory, 1685...thread processing unit, 1686...filter coefficient Update unit, 1687... histogram addition unit, 1688... polarization multiplicity identification unit, 1784... shared memory, 1785... identification unit, 16841... filter coefficient storage unit, 16842... amplitude histogram storage unit, 16851... adaptive filter, 16852... amplitude histogram information generation unit, 16853... quantization unit, 16854... normalization unit (X polarization), 16855... normalization unit (Y polarization), 16856... identification unit (X polarization), 16857... identification unit (Y polarization), 17843... learning data storage unit, 17856... identification unit (X polarization), 17857... identification unit (Y polarization),

Claims

1. a scheme identification unit that identifies a frame format of a received signal based on a bit string pattern of a preamble after demodulation of the received signal; a function control unit that controls a signal processing function according to a result of the frame format identification by the format identification unit to be operated; a signal processing unit that is controlled to operate by the function control unit and processes the received signal; Equipped with The function control unit controls to activate a frame detection function corresponding to the frame format identified by the format identification unit. Transmission equipment.

2. The function control unit activates a signal processing function according to the identification result and allocates resources for the signal processing function to operate.

2. The transmission device according to claim 1.

3. The scheme identification unit further identifies a modulation scheme of the received signal based on a frequency distribution of the amplitude of the received signal; The function control unit further controls to activate a demodulation function corresponding to the modulation method identified by the method identification unit.

3. A transmission device according to claim 1 or 2.

4. The method identification unit further performs a process of demodulating a code included in a frame detected from the received signal, and identifies the coding method of the received signal based on an amount of errors generated by the demodulation process; The function control unit further controls to operate a decoding function corresponding to the encoding method identified by the method identification unit. A transmission device according to any one of claims 1 to 3.

5. a function control unit that receives from the transmission device information on an identification result regarding a frame format of the received signal, the identification result being identified based on a bit string pattern of a preamble after demodulation of the signal received by the transmission device, and controls the transmission device to operate a signal processing function corresponding to the received identification result; Equipped with the function control unit controls to activate a frame detection function according to the identified frame format. Function control device.

6. A system including a terminal device and a transmission device, the terminal device transmits a signal to the transmission device, The transmission device includes: a scheme identification unit that identifies a frame format of the received signal based on a bit string pattern of a preamble after demodulation of the signal received from the terminal device; a function control unit that controls a signal processing function according to a result of the frame format identification by the format identification unit to be operated; a signal processing unit that is controlled to operate by the function control unit and processes the received signal; Equipped with The function control unit controls to activate a frame detection function corresponding to the frame format identified by the format identification unit. system.

7. A method identification unit identifies a frame format of the received signal based on a bit string pattern of a preamble after demodulation of the received signal; A function control unit controls a signal processing function according to a result of the frame format identification by the format identification unit to be activated; a signal processing unit that is controlled by the function control unit so that a signal processing function corresponding to the identification result is activated, and processes the received signal; 1. A signal processing method, comprising: The function control unit controls to activate a frame detection function corresponding to the frame format identified by the format identification unit. Signal processing methods.

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