WO2022068680A1 - Decoding method, receiving device, and storage medium - Google Patents

Abstract

Disclosed in the embodiments of the present invention are a decoding method, a receiving device, and a storage medium, which are used to suppress inter-symbol interference by means of the correlation between at least two symbols adjacent to one another, thus avoiding the loss of effective information conducive to decoding. The method comprises: a receiving device converts a received optical signal so as to obtain information to be detected, the information to be detected comprising a plurality of packets, each packet comprising a plurality of symbols, the plurality of symbols being mapped onto at least one constellation point comprised in a constellation map of the optical signal, and the at least one constellation point being transmitted by means of at least two consecutive time slots; the receiving device obtains target joint soft information corresponding to a target packet, the target joint soft information being used to indicate various values of the target packet, and the target packet being one of the plurality of packets; and the receiving device performs forward error correction (FEC) decoding on the target joint soft information so as to obtain the original signal of the target packet.

Description

A decoding method, receiving device and storage medium

This application claims the priority of the Chinese patent application with the application number 202011066380.0 and the application title "A Decoding Method, Receiving Device and Storage Medium" filed with the State Intellectual Property Office of China on September 30, 2020, the entire contents of which are by reference Incorporated in this application.

technical field

The present application relates to the field of communications, and in particular, to a decoding method, a receiving device, and a storage medium.

Background technique

In a communication system, the channel between the transmitting device and the receiving device is affected by intersymbol interference (ISI) impairments, which degrades the performance of the communication system.

In order to achieve the suppression of ISI damage, the receiving device can perform a series of processing on the received signal, such as demultiplexing, polarization separation, frequency mixing, analog-to-digital conversion, dispersion compensation, equalization, phase recovery and filtering. The sequence detection module included in the receiving device performs sequence detection on the processed signal to obtain soft information, and the forward error correction (FEC) decoding module can restore the original signal according to the soft information.

In the prior art, the sequence detection module inputs the soft information of each symbol to the FEC decoding module, but the soft information of two adjacent symbols has a correlation and is scattered before being input to the FEC decoding module, which is helpful for decoding. The valid information cannot be transmitted to the receiving device, resulting in the loss of valid information, reducing the effect of suppressing ISI damage, and reducing the accuracy of decoding.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a decoding method, a receiving device, and a storage medium, which are used to acquire the correlation between at least two adjacent symbols, and suppress ISI damage through the correlation.

A first aspect of the embodiments of the present invention provides a decoding method. The method includes: a receiving device converts a received optical signal to obtain information to be detected, where the information to be detected includes a plurality of groups, and each group includes a plurality of symbols , the multiple symbols are mapped to at least one constellation point included in the constellation diagram of the optical signal, and the at least one constellation point is transmitted through at least two consecutive time slots; the receiving device obtains the target joint soft information corresponding to the target grouping , the target joint soft information is used to indicate various values of the target group, and the target group is one of the multiple groups; the receiving device performs forward error correction (FEC) decoding on the target joint soft information to obtain The original signal of this target packet.

It can be seen that in the process of decoding the information to be detected, the information to be detected needs to be grouped, and each group includes a plurality of symbols mapped to at least one constellation point included in the constellation diagram. It can be seen that each group passes through at least two symbols. consecutive time slots for transmission. For example, a packet includes a first symbol and a second symbol, the first symbol and the second symbol are mapped to two different constellation points, and the two constellation points are transmitted through two different and consecutive time slots. In another example, the first symbol and the second symbol are mapped to the same constellation point, and the constellation point used to transmit the first symbol and the constellation point used to transmit the second symbol are transmitted through two different and consecutive time slots . Thus, each packet transmits the correlation between at least two consecutive time slots in the channel.

Moreover, the target joint soft information obtained by the receiving device includes the correlation between at least two consecutive time slots in the channel used for transmitting the target packet, which effectively avoids the loss of valid information that is helpful for decoding. In order to indicate the correlation between at least two consecutive time slots used for transmitting the target packet, the accuracy of decoding the information to be detected is effectively improved, and the effect of suppressing ISI damage is effectively improved.

Because the joint soft information of the target packet can not only transmit various values of the target packet, but also can indicate the correlation between at least two consecutive time slots used to transmit the target packet, it can be seen that the Joint soft information transmits more information, thereby bringing greater performance gains to decoding performance.

Based on the first aspect, in an optional implementation manner, after the receiving device obtains the target joint soft information corresponding to the target group, the method further includes: the receiving device de-interleaves the target joint soft information to obtain a de-interleaving sequence ; the receiving device performing forward error correction FEC decoding on the target joint soft information to obtain the original signal of the target packet includes: the receiving device performing FEC decoding on the de-interleaving sequence to obtain the original signal of the target packet.

It can be seen that the receiving device performs de-interleaving processing on the entire target packet, thereby effectively ensuring that the de-interleaving processing will not break up the correlation between at least two time slots in the channel transmitted by the target packet, effectively avoiding the The loss of decoded valid information improves the decoding accuracy of the information to be detected, and effectively guarantees the effect of suppressing ISI damage.

Based on the first aspect, in an optional implementation manner, the obtaining, by the receiving device, the target joint soft information corresponding to the target packet includes: the receiving device performs sequence detection on the target packet to obtain the target joint soft information.

It can be seen that the receiving device can directly perform sequence detection according to the target packet to obtain the target joint soft information, so that the packet can be accurately decoded without repeated iterations, and the complexity and efficiency of the decoding process are reduced.

Based on the first aspect, in an optional implementation manner, before the receiving device obtains the target joint soft information corresponding to the target group, the method further includes: the receiving device performs FEC decoding on the joint soft information corresponding to the target group to obtain Joint soft information after FEC decoding; the receiving device performs sequence detection on the joint soft information after FEC decoding to obtain the target joint soft information.

It can be seen that the receiving device can iterate the joint soft information corresponding to the target packet, thereby effectively improving the decoding accuracy of the information to be detected, and effectively improving the system performance. Due to the process of iterating the joint soft information of the target grouping each time, more information is transmitted, which effectively ensures the accuracy of the joint soft information output after the sequence detection, and brings greater performance benefits to the iterative performance. .

Based on the first aspect, in an optional implementation manner, the receiving device performing sequence detection on the FEC-decoded joint soft information to obtain the target joint soft information includes: the receiving device interleaving the FEC-decoded joint soft information to obtain the interleaved sequence; the receiving device performs sequence detection on the interleaved sequence to obtain the target joint soft information.

It can be seen that the receiving device effectively improves the accuracy of the joint soft information of the target packet obtained by the receiving device in the iterative process by interleaving the joint soft information after FEC decoding to obtain an interleaved sequence.

Based on the first aspect, in an optional implementation manner, before the receiving device converts the received optical signal to obtain the information to be detected, the method further includes: the receiving device determines at least one first information included in the information to be detected. A symbol and at least one second symbol, wherein the at least one first symbol is mapped to a first constellation point, the at least one second symbol is mapped to a second constellation point, the at least one first symbol and the at least one first symbol The two symbols are located adjacent to each other in the information to be detected; the receiving device divides all the first symbols in the at least one first symbol and all the second symbols in the at least one second symbol into the target group. Wherein, the first constellation point and the second constellation point may be the same constellation point, or may be two constellation points that are different from each other.

Based on the first aspect, in an optional implementation manner, before the receiving device converts the received optical signal to obtain the information to be detected, the method further includes: the receiving device determines at least one first information included in the information to be detected. A symbol and at least one second symbol, wherein the at least one first symbol is mapped to a first constellation point, the at least one second symbol is mapped to a second constellation point, the at least one first symbol and the at least one first symbol Two symbols are adjacent in the information to be detected; the receiving device divides all the first symbols in the at least one first symbol and all the second symbols in the at least one second symbol into a first group; the receiving device The device divides the first group into a plurality of second groups, wherein the second group is the target group, the number of symbols included in the second group is smaller than the number of symbols included in the first group, and the number of symbols included in the second group is A plurality of symbols are mapped to at least one constellation point included in the constellation diagram of the optical signal, and the second packet is transmitted through at least two time slots.

It can be seen that, because the number of symbols included in the second group is smaller than the number of symbols included in the first group, in the process of decoding each second group, the difficulty of decoding can be effectively reduced and the decoding efficiency can be improved.

Based on the first aspect, in an optional implementation manner, the target joint soft information includes multiple values that the target group has, and a probability of any one of the multiple values.

Based on the first aspect, in an optional implementation manner, the target joint soft information includes any two values of multiple values possessed by the target group, and the logarithm of the ratio of the probabilities of the two values .

A second aspect of an embodiment of the present invention provides a receiving device, the receiving device includes: a conversion module configured to convert a received optical signal to obtain information to be detected, where the information to be detected includes a plurality of groups, each of which Including a plurality of symbols, the plurality of symbols are mapped to at least one constellation point included in the constellation diagram of the optical signal, and the at least one constellation point is transmitted through at least two consecutive time slots; the sequence detection module is used to obtain the target The target joint soft information corresponding to the grouping, the target joint soft information is used to indicate various values of the target grouping, and the target grouping is one of the multiple groups; the forward error correction FEC decoding module is used to The target joint soft information is subjected to forward error correction FEC decoding to obtain the original signal of the target packet.

For the description of the beneficial effects of the receiving device shown in this aspect, please refer to the description in the first aspect, and details will not be repeated.

Based on the second aspect, in an optional implementation manner, the receiving device further includes a de-interleaving module, where the de-interleaving module is configured to de-interleave the target joint soft information to obtain a de-interleaving sequence; the FEC decoding module further is used to perform FEC decoding on the deinterleaved sequence to obtain the original signal of the target packet.

Based on the second aspect, in an optional implementation manner, the sequence detection module is specifically configured to perform sequence detection on the target packet to obtain the target joint soft information.

Based on the second aspect, in an optional implementation manner, the FEC decoding module is further configured to: perform FEC decoding on the joint soft information corresponding to the target group to obtain the joint soft information after FEC decoding; the sequence detection module is further configured to: , and perform sequence detection on the joint soft information after FEC decoding to obtain the target joint soft information.

Based on the second aspect, in an optional implementation manner, the receiving device further includes an interleaving module, where the interleaving module is configured to interleave the joint soft information after FEC decoding to obtain an interleaving sequence; the sequence detection module is further configured to , and perform sequence detection on the interleaved sequence to obtain the target joint soft information.

Based on the second aspect, in an optional implementation manner, the sequence detection module is further configured to: determine at least one first symbol and at least one second symbol included in the information to be detected, wherein the at least one first symbol Mapped to the first constellation point, the at least one second symbol is mapped to the second constellation point, the at least one first symbol and the at least one second symbol are adjacent in the information to be detected; the at least one first symbol and the at least one second symbol are located adjacent to each other; At least part of the first symbol in a symbol and at least part of the second symbol in the at least one second symbol are divided into the target group.

Based on the second aspect, in an optional implementation manner, the target joint soft information includes multiple values that the target group has, and a probability of any one of the multiple values.

Based on the second aspect, in an optional implementation manner, the target joint soft information includes any two values of multiple values possessed by the target group, and the logarithm of the ratio of the probabilities of the two values .

A third aspect of the embodiments of the present invention provides a receiving device, including a processor, a memory, and a receiver, where the processor is respectively interconnected with the memory and the receiver through a line; the receiver is configured to receive an optical signal from a transmitting device, The processor is configured to call the program code in the memory to execute the method shown in any one of the above-mentioned first aspect.

For the description of the beneficial effects shown in this aspect, please refer to the above-mentioned first aspect for details, and details will not be repeated.

A fourth aspect of the embodiments of the present invention provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is executed by hardware, is used to execute the method shown in any one of the foregoing first aspects.

A fifth aspect of the embodiments of the present invention provides a communication system, including a sending device and a receiving device;

The sending device is configured to send an optical signal to a receiving device, and the receiving device is configured to execute the method shown in any one of the above-mentioned first aspect.

Description of drawings

FIG. 1a is an exemplary structural diagram of an embodiment of a sending device provided by the application;

Fig. 1b is a structural example diagram of the first embodiment of the receiving device provided by the application;

Fig. 2 is a flow chart of the steps of the first embodiment of the decoding method provided by the application;

FIG. 3 is a flowchart of the steps of the second embodiment of the decoding method provided by the application;

FIG. 4 is a schematic structural diagram of a second embodiment of the receiving device provided by the application;

5 is a flowchart of steps of a third embodiment of the decoding method provided by the application;

FIG. 6 is a structural example diagram of a third embodiment of the receiving device provided by the present application.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

In order to better understand the decoding method provided by the application, the following first describes the communication system to which the decoding method shown in the application is applied:

The communication system shown in this embodiment is a coherent optical fiber communication system, and the communication system includes a sending device and a receiving device. The sending device is used for sending an optical signal to the receiving device, and the receiving device is used for decoding the optical signal to obtain the original signal.

The sending device will be described below with reference to Fig. 1a, wherein Fig. 1a is a diagram showing an example structure of an embodiment of the sending device provided by the present application.

The sending device 101 includes an FEC encoding module 103, an interleaver 104, a data distribution module 121, two constellation mapping modules (ie, constellation mapping modules 105 and 106), and four pre-filtering modules (ie, pre-filtering modules 107, 108, 109 and 110), four shaping modules (ie, shaping modules 111, 112, 113 to 114), four digital-to-analog conversion modules (ie, digital-to-analog conversion modules 115, 116, 117, and 118), two modulators (ie, modulation 119 and 120) and multiplexer 123.

It should be clearly stated that the description of the structure of the sending device 101 in this embodiment is an optional example, which is not limited, as long as the sending device 101 can convert the original signal into an optical signal and transmit it to the receiving device. For example, four pre-filtering modules can be combined into four shaping modules respectively.

In this embodiment, when the input signal input to the sending device 101 is a real number signal, the sending device 101 includes four pre-filters and four shaping modules. If the input signal input to the sending device 101 is In the case of complex signals, the transmitting device 101 includes two prefilters and two shaping modules. In this embodiment, the input signal is a real signal as an example for illustrative description.

The functions of the FEC encoding module 103, the interleaver 104, the constellation mapping module, the pre-filtering module, the shaping module, the digital-to-analog conversion module, and the multiplexer 123 shown in this embodiment can be implemented by software. The processor executes the computer program stored in the memory to perform the functions corresponding to the above-mentioned devices. The above-mentioned devices may also be independent chips for performing corresponding functions.

The following briefly describes the functions of each device included in the sending device 101:

The FEC encoding module 103 is configured to group the original signals, and perform FEC encoding on the bits included in each group to obtain the FEC-encoded signals.

For example, if the Galois field (GF) of the FEC encoding module is GF(2^n), then the FEC encoding module 103 can take every n bits of the original signal as a group to correspond to a symbol, and for this The symbols are FEC encoded to obtain FEC encoded signals.

The interleaver 104 is used to interleave the FEC encoded signal to obtain an interleaved sequence. The interleaver 104 is used to change the information structure of the FEC-encoded signal to the greatest extent without changing the information content of the FEC-encoded signal.

The data distribution module 121 is configured to transmit the interleaved sequence to the constellation mapping module, and the constellation mapping module is configured to perform constellation mapping on the interleaved sequence to map onto the constellation diagram, and specifically, map each symbol included in the interleaved sequence to the constellation diagram on the constellation point.

For example, if the interleaving sequence is "0101001010101010...", the data distribution module 121 can divide the interleaving sequence into two data streams (ie, the first data stream and the second data stream) for input to the constellation mapping module 105 and the constellation mapping respectively. Module 106, wherein the interleaving sequence can be divided into two data streams in an interleaved manner with two symbols as a group, the first data stream is "01001010...", and the second data stream is "01101010..." . Of course, there are many ways to allocate data streams, which are not listed here.

The constellation mapping module 105 is configured to map the first data stream to the constellation diagram, and the constellation mapping module 106 is further configured to map the second data stream to the constellation diagram.

Specifically, the constellation mapping module can map "00" to constellation point 1+j, map "01" to constellation point-1+j, map "10" to constellation point-1-j, and map "01" to constellation point-1-j. 11" is mapped to the constellation points 1-j.

It can be seen that the constellation mapping module 105 maps the first data stream "01001010..." to the constellation points of "-1+j, 1+j, -1-j, -1-j..." respectively. The constellation mapping module 105 separates the real part and the imaginary part of each constellation point as two outputs, and can obtain the output real part of the first mapping signal "-1, 1, -1, -1..." and the output The second mapping signal of the imaginary part is "1, 1, -1, -1...".

It can be understood that the constellation mapping module 106 can also map the second data stream "01101010..." to the constellation points "-1+j, -1-j, -1-j, -1-j..." respectively . The constellation mapping module 106 separates the real part and the imaginary part of each constellation point as two outputs, and can obtain the output real part of the third mapping signal "1, -1, -1, -1..." and the output imaginary The fourth mapping signal "1, -1, -1, -1" of the part.

It can be seen that the two data streams can obtain four mapped signals through the constellation mapping module. There are many ways of constellation mapping shown in this embodiment. In this embodiment, only two symbols are mapped to the same constellation point as an example for illustration. In other implementations, three symbols may also be used. Or 4 symbols are a group for constellation mapping, etc., which is not specifically limited.

The pre-filtering modules 107 , 108 , 109 and 110 are respectively used for pre-filtering the four-channel mapped signals to obtain the four-channel filtered signals. The pre-filtering is finite impulse response filtering, the bandwidth of the filtered signal is smaller than the bandwidth of the mapped signal, and the filtered signal is a baud rate signal. Therefore, after pre-filtering, compared with the mapped signal before pre-filtering, the information of the filtered signal is not lost, but the occupied bandwidth is narrowed.

The shaping modules 111 , 112 , 113 to 114 are used to respectively perform waveform shaping on the four-channel filtered signals to correspondingly obtain the four-channel shaped signals.

The digital-to-analog conversion modules 115 , 116 , 117 and 118 are respectively used to perform digital-to-analog conversion on the four channels of shaped signals to obtain four channels of analog signals.

The modulator 119 is used to modulate the two analog signals from the digital-to-analog conversion modules 115 and 116 to output one modulated signal, and the modulator 120 is used to modulate the two analog signals from the digital-to-analog conversion modules 117 and 118 to modulate Output another modulated signal.

The multiplexer 123 is used to multiplex the two modulated signals into an optical signal, and transmit the optical signal to a channel connected between the sending device 101 and the receiving device, and the channel shown in this embodiment is an optical fiber.

During the transmission of the signal to the receiving device in the optical fiber, channel impairment occurs. The channel impairment can be equalized by the receiving device. The specific structure of the receiving device 102 is optionally described below with reference to FIG. 1b:

The receiving device 102 includes a local laser 125, a polarization multiplexing coherent front end 126, four analog-to-digital converters (ie, analog-to-digital converters 127, 128, 129, and 130), and two dispersion compensation modules (ie, dispersion compensation modules 131 and 132) , a polarization compensation module 133, two phase recovery modules (ie, phase recovery modules 134 and 135), four post-filter modules (ie, post-filter modules 136, 137, 138, and 139), four sequence detection modules (ie, sequence detection modules 140 , 141 , 142 and 143 ), a de-interleaving module 145 and an FEC decoding module 144 .

It should be clearly stated that the description of the structure of the receiving device 102 in this embodiment is an optional example, which is not limited, as long as the receiving device 102 can convert the optical signal from the transmitting device 101 into an original signal.

The functions of the polarization multiplexing coherent front end 126, the analog-to-digital converter, the dispersion compensation module, the polarization compensation module 133, the phase recovery module, the post-filtering module, the sequence detection module, the de-interleaving module, and the FEC decoding module shown in this embodiment can be determined by Software implementation, specifically, the processor included in the receiving device executes the computer program stored in the memory, so as to execute the functions corresponding to the above-mentioned components. The above-mentioned devices may also be independent chips for performing corresponding functions.

The polarization multiplexing coherent front end 126 is used for decoupling the optical signal from the sending device 101 to obtain the decoupled optical signal, and the polarization multiplexing coherent front end 126 is also used for polarization separation of the decoupled optical signal to form the first path The modulated signal and the second modulated signal, the polarization multiplexing coherent front end 126 is also used to mix the optical signal from the local laser 125 and the modulated signal of the first modulated signal to restore the first modulated signal and the second modulated signal of the low-frequency baseband The polarization multiplexing coherent front-end 126 is also used to mix the optical signal from the local laser 125 and the second modulated signal to restore the low frequency baseband third and fourth analog signals.

The analog-to-digital converters 127, 128, 129, and 130 are respectively used to perform analog-to-digital conversion on the four channels of analog signals to obtain four channels of digital signals, namely the first channel digital signal, the second channel digital signal, the third channel digital signal and the third channel digital signal. Four digital signals.

The dispersion compensation module 131 is used for performing dispersion compensation on the first channel digital signal and the second channel digital signal to obtain the first channel dispersion compensation signal, and the dispersion compensation module 132 is used for performing dispersion compensation on the third channel digital signal and the fourth channel digital signal Compensation to obtain the second channel dispersion compensation signal.

The polarization compensation module 133 is configured to perform polarization compensation on the first channel of dispersion compensation signal and the second channel of dispersion compensation signal, so as to obtain the first channel of polarization compensation signal and the second channel of polarization compensation signal.

The phase recovery module 134 is configured to perform phase recovery on the first channel of dispersion compensation signal to output the first channel of equalization recovery signal and the second channel of equalization recovery signal, and the phase recovery module 135 is configured to perform phase recovery on the second channel of dispersion compensation signal to output The third channel of equalization recovery signal and the fourth channel of equalization recovery signal.

The post-filtering modules 136, 137, 138, and 139 are respectively used for post-filtering the four-channel equalized restoration signals to obtain four-channel filtered signals, namely the first-channel filtered signal, the second-channel filtered signal, and the third-channel filtered signal. The filtered signal and the fourth filtered signal.

The sequence detection modules 140, 141, 142, and 143 are respectively used to perform sequence detection on the four-channel filtered signals to output the four-channel sequence signals, namely the first-channel sequence signal, the second-channel sequence signal, the third-channel sequence signal, and the fourth-channel sequence signal. road sequence signal.

The de-interleaving module 145 is used for de-interleaving the four-channel sequence signal and then inputting it to the FEC decoding module 144 .

The FEC decoding module 144 is configured to perform FEC decoding on the first-channel sequence signal, the second-channel sequence signal, the third-channel sequence signal, and the fourth-channel sequence signal, so as to obtain the original signal.

The following describes how the receiving device 102 implements the process of suppressing the ISI impairment of the channel in the existing solution:

Specifically, the receiving device 102 can suppress the ISI damage through the post-filtering module and the sequence detection module, wherein the white noise superimposed on the channel of the optical signal from the transmitting device 101 is amplified by channel equalization, and the post-filtering The module is capable of filtering out noise.

In addition, the post-filtering module can convert wideband signals into narrowband signals to introduce controllable inter-symbol crosstalk, and then the sequence detection module can suppress the influence of ISI damage and improve system performance.

The sequence detection module can use the Viterbi algorithm or the BCJR algorithm to perform sequence detection on the signal from the post-filtering module to suppress ISI damage.

In order to enable the FEC decoding module 144 to obtain the original signal, the sequence detection module needs to input the soft information of each symbol in each channel of the sequence signal to the FEC decoding module 144 .

For example, if the transmitting device encodes the original signal by means of binary FEC encoding, the soft information L of each symbol can be shown in the following formula 1:

Formula 1:

As shown in Equation 1, the soft information of each symbol input to the FEC decoding module 144 is the logarithm of the probability that the symbol takes 0 divided by the probability that the symbol takes 1.

In this example, the sending device side uses binary FEC encoding to encode the original signal as an example for illustration. In other examples, the sending device may also use non-binary FEC encoding to encode the original signal. For such an example The description of soft information under the nature will not be repeated.

However, the soft information obtained by the existing solution is for each symbol, and the greater the ISI of the channel, the greater the correlation of the soft information between at least two adjacent symbols. For example, when the FEC decoding module 144 performs FEC decoding on the signal "0110001...", it can input the soft information of each symbol included in the signal "0110001..." to the FEC decoding module, specifically, the soft information for the symbol "0" "L1", soft information "L2" for symbol "1", etc. When the ISI of the channel is relatively large, the correlation between the soft information "L1" for the symbol "0" and the soft information "L2" for the symbol "1" output by the sequence detection module is relatively large, but the adjacent ones are at least The correlation between the soft information of two symbols When the de-interleaving process is performed by the de-interleaving module, the correlation between the soft information of the adjacent at least two symbols is scattered, resulting in effective information that is helpful for decoding , reducing the effect of suppressing ISI damage and reducing the accuracy of decoding.

By using the method shown in this application, ISI damage can be effectively suppressed and the decoding accuracy can be effectively improved, which is specifically described with reference to FIG. 2 , wherein FIG. 2 is the first implementation of the decoding method provided by the application. Example step flow chart.

Step 201: The receiving device receives an optical signal from the transmitting device.

The sending device processes the original signal to generate the corresponding optical signal, and transmits the optical signal to the receiving device through the optical fiber between the sending device and the receiving device. For the specific process of sending the optical signal to the receiving device, please refer to Referring to the embodiment shown in FIG. 1a, details are not repeated in this embodiment.

It can be seen that the receiving device can receive the optical signal from the transmitting device through the optical fiber.

Step 202: The receiving device converts the optical signal to obtain the information to be detected.

Specifically, the receiving device can sequentially convert the optical signal through a polarization multiplexing coherent front end, an analog-to-digital converter, a dispersion compensation module, a polarization compensation module, a phase recovery module, and a post-filtering module to obtain the information to be detected. For description, please refer to the embodiment shown in FIG. 1b, and details are not repeated in this embodiment.

It can be seen that, as shown in this embodiment, the four post-filters output four channels of information to be detected, and the steps shown in the subsequent steps are to process one channel of information to be detected output by each post-filter.

Step 203: The receiving device divides the information to be detected to form multiple groups.

The execution subject of this step is the sequence detection module of the receiving device. For the specific description of the sequence detection module, please refer to the embodiment shown in FIG. 1 b , which will not be described in detail.

In this embodiment, the receiving device divides the information to be detected so that each group includes multiple symbols, and the multiple symbols located in each group are mapped to at least one constellation point included in the constellation diagram of the optical signal, Wherein, the at least one constellation point is transmitted through at least two consecutive time slots.

Taking the first symbol and the second symbol included in the information to be detected as an example, how to perform grouping is described:

The number of first symbols may be one or more, the number of second symbols may also be one or more, and at least one first symbol and at least one second symbol are located adjacent to each other in the information to be detected.

The transmitting device has mapped at least one first symbol to the first constellation point and has mapped at least one second symbol to the second constellation point.

Among them, the first constellation point and the second constellation point need to meet the following conditions:

The first constellation point and the second constellation point are two different constellation points on the constellation diagram of the optical signal, or the first constellation point and the second constellation point are the same constellation point on the constellation diagram of the optical signal. In order to transmit the correlation between the soft information of the first symbol and the soft information of the second symbol to the receiving device, the time slot for transmitting the first constellation point and the time slot for transmitting the second constellation point are consecutive and mutually exclusive. same.

Under the condition that the first constellation point and the second constellation point satisfy the above-mentioned conditions, the receiving device can divide at least one first symbol and at least one second symbol into the same group.

It should be clear that the above description takes the symbols mapped to two constellation points in the same group as an example for illustration, and in other examples, the same group may also include symbols mapped to more than two constellation points. , which is not specifically limited in this embodiment.

For example, the group includes at least one symbol mapped to the first constellation point, at least one symbol mapped to the second constellation point, and so on, and also includes at least one symbol mapped to the Mth constellation point, The value of M can be a positive integer greater than or equal to 3.

The method of dividing the information to be detected is not limited in this embodiment, as long as the multiple symbols included in each divided group are mapped to at least one constellation on the constellation diagram of the optical signal On the point, the at least one constellation point can be transmitted in at least two consecutive time slots.

For better understanding, the following is an illustrative description with specific examples:

Example 1

In this example, the optical signal is a binary phase shift keying (BPSK) optical signal as an example to illustrate:

In this example, during the constellation mapping process, the transmitting device may map each symbol to one constellation point. For example, in the process of performing constellation mapping on the symbol stream "10100...", the first symbol "1" of the symbol stream is mapped to the first constellation point (for example, the first constellation point may be "1") , the second symbol "0" of the symbol stream is mapped to the second constellation point (for example, the second constellation point may be "-1"), wherein the first constellation point and the second constellation point may be the same It may also be different, which is not specifically limited in this embodiment. In this example, the first constellation point and the second constellation point are different as an example for illustrative description.

In this example, the information to be detected is {b ₁ b ₂ b ₃ b ₄ ...} as an example. In this embodiment, grouping can be performed according to the GF of the FEC decoding module of the receiving device. Specifically, if the GF of the FEC decoding module is GF ( 2^n), it can be determined that each packet includes n symbols that are adjacent in the information to be detected.

For example, if the GF of the FEC decoding module is GF(2^2), it can be known that each group includes 2 symbols. Specifically, if the information to be detected is {b ₁ b ₂ b ₃ b ₄ …}, it is divided into The first grouping is {b ₁ b ₂ }, the second is {b ₃ b ₄ }, and so on.

It can be seen from the above description that in this example, each symbol is mapped to one constellation point, and the two adjacent symbols are mapped to different constellation points. Specifically, the first grouping is included in {b ₁ b ₂ } The two symbols of are mapped to two different constellation points, and the two symbols included in the first group {b ₁ b ₂ } are transmitted through two different consecutive time slots in the channel. It can be seen that when n is 2, each packet transmits the correlation between two consecutive time slots in the channel.

Example 2

In this example, the optical signal is a BPSK optical signal as an example for illustrative description, wherein the information to be detected is {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ …}.

The GF of the FEC decoding module is GF(2^n). In this example, taking the value of n as 3 as an example, it can be known that each packet includes 3 symbols. Specifically, the information to be detected {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ ... } divides the first group into {b ₁ b ₂ b ₃ }, the second as {b ₄ b ₅ b ₆ }, and so on.

In this example, each symbol is mapped to one constellation point, and three adjacent symbols are mapped to three different constellation points. It can be known that the three symbols included in the first group {b ₁ b ₂ b ₃ } symbols are mapped to three constellation points, and the three constellation points mapped to the three symbols included in the first group {b ₁ b ₂ b ₃ } are carried out through three different and consecutive time slots in the channel. transmission.

It can be seen that when n is 3, each packet transmits the correlation between three consecutive time slots in the channel.

The description of the value of n in Example 1 and Example 2 is an example and not limited. In other examples, n can also take a higher-order value, for example, n takes a value of 4, 6, or other values.

This example does not limit the specific value of n, as long as n is a positive integer greater than or equal to 2.

Example 3

In Example 1 and Example 2, it is taken as an example that any two adjacent symbols in the information to be detected are mapped to two constellation points, while in this example, two or more adjacent symbols in the information to be detected are taken as an example How to group when mapped to the same constellation point.

For example, in this example, the optical signal is a four-level pulse amplitude modulation (PAM4) optical signal as an example for illustrative illustration:

In this example, in the process of constellation mapping, the transmitting device can map every two adjacent symbols to the same constellation point, for example, the symbol stream to be subjected to constellation mapping is {I ₁ I ₂ I ₃ I ₄ … ...}, divide the symbol stream to be subjected to constellation mapping to form multiple packets to be mapped, and the multiple packets to be mapped may be {I ₁ I ₂ }{I ₃ I ₄ }..., where {I ₁ I ₂ } is the first symbol and the second symbol in the symbol stream to be subjected to constellation mapping, {I ₃ I ₄ } is the third symbol and the fourth symbol in the symbol stream to be subjected to constellation mapping, and so on.

If the value of {I ₁ I ₂ } is 00, the sending device can map {I ₁ I ₂ } to the constellation point "-3"; if the value of {I ₁ I ₂ } is 01, the sending device {I ₁ I ₂ } can be mapped to the constellation point "-1", if the value of {I ₁ I ₂ } is 10, the sending device can map {I ₁ I ₂ } to the constellation point "3" , if the value of {I ₁ I ₂ } is 11, the sending device can map {I ₁ I ₂ } to the constellation point "1".

For example, the receiving device converts the optical signal from the transmitting device to obtain the information to be detected {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ b ₇ b ₈ …}. The receiving device can perform grouping according to the GF of the FEC decoding module of the receiving device. Specifically, if the GF of the FEC decoding module is (2^n), it can be determined that each grouping includes n symbols that are adjacent to each other in the information to be detected. .

For example, if the GF of the FEC decoding module is _GF ( _{2 ^ 4} ), it can be known that each _packet includes _{4 symbols} . b ₈ ... }, the first grouping is {b ₁ b ₂ b ₃ b ₄ }, the second grouping is {b ₅ b ₆ b ₇ b ₈ }, and so on.

It can be seen from the above description that in this example, every two symbols are mapped to one constellation point, and the constellation points mapped to every two adjacent symbols are transmitted through two consecutive different time slots. It can be seen that the first The four symbols included in the grouping {b ₁ b ₂ b ₃ b ₄ } are mapped to two constellation points transmitted through two consecutive time slots, and it can be known that the first group {b ₁ b ₂ b ₃ The four symbols included in b ₄ } are transmitted in two different and consecutive time slots in the channel. It can be seen that when n is 4, each packet transmits the correlation between two consecutive time slots in the channel.

That is, {b ₁ b ₂ } is mapped to the first constellation point, and {b ₃ b ₄ } is mapped to the second constellation point. In this example, the first constellation point and the second constellation point may be the same constellation point, The constellation points may also be different, as long as the time slot for transmitting the first constellation point and the time slot for transmitting the second constellation point are adjacent and different from each other.

It should be clear that the above description of the example of the grouping is only an example, and it is not limited, as long as each grouping of the information to be detected is divided, the symbols included are mapped to at least one constellation point to pass the information. Two or more than two consecutive time slots may be used for transmission, so that each packet can transmit the correlation between at least two consecutive time slots in the channel.

Step 204: The receiving device acquires target joint soft information corresponding to the target group.

The execution subject of this step may be the sequence detection module of the receiving device, and the target group shown in this embodiment is any one of multiple groups that the receiving device divides the information to be detected.

The target joint soft information is used to indicate various values of the target group, so that the FEC decoding module of the receiving device can decode each symbol included in the target group according to the target joint soft information.

For example, the target joint soft information includes multiple values that the target group has, and the probability of each value.

Combined with the above example 1, the target joint soft information is described:

If the target grouping is {b ₁ b ₂ }, the target joint soft information s ₁ includes: if {b ₁ b ₂ }={00}, the probability that the target grouping is 0 is P1, and if {b ₁ b ₂ }={01}, then the probability of the target group taking a value of 1 is P2, if {b ₁ b ₂ }={10}, then the probability of the target group taking a value of 2 is P3, if {b ₁ b ₂ }= {11}, then the probability that the target grouping value is 3 is P4, as shown in Table 1 below:

Table 1

target grouping	value	probability
{b 1 b 2 }={00}	0	P1
{b 1 b 2 }={01}	1	P2
{b 1 b 2 }={10}	2	P3
{b 1 b 2 }={11}	3	P4

It can be seen that the receiving device can obtain a plurality of joint soft information {s ₁ s ₂ … } for the information to be detected {b ₁ b ₂ b ₃ b ₄ …}, where the joint soft information s ₂ is a group {b ₃ b For the joint soft information of ₄ }, for the description of s ₂ , please refer to the above description of s ₁ of the target group {b ₁ b ₂ }, and details are not repeated.

Optionally, the sequence detection module shown in this embodiment may send partial probability values of the target grouping to the FEC decoding module. Specifically, in the case that the target joint soft information of the target grouping has M probability values, the sequence The detection module can send M-1 probability values to the FEC decoding module, and the FEC decoding module can obtain each probability value included in the joint soft information of the target group. For example, as shown in Table 1, the sequence detection module can convert P1, P2 And P3 is sent to the FEC decoding module, and the FEC decoding module can calculate P4=1-P1-P2-P3.

Combined with the above example 2, the target joint soft information is described:

If the target grouping is {b ₁ b ₂ b ₃ }, the target joint soft information s ₁ includes: if {b ₁ b ₂ b ₃ }={000}, the probability that the target grouping is 0 is P1, and if { b ₁ b ₂ b ₃ }={001}, then the probability of the target group taking a value of 1 is P2, and if {b ₁ b ₂ b ₃ }={011}, then the probability that the target group taking a value of 3 is P3, If {b ₁ b ₂ b ₃ }={111}, the probability that the target group takes a value of 7 is P4; if {b ₁ b ₂ b ₃ }={010}, the probability that the target group takes a value of 2 is P5, if {b ₁ b ₂ b ₃ }={100}, the probability of the target group taking a value of 4 is P6, if {b ₁ b ₂ b ₃ }={110}, then the target group taking a value of 6 The probability is P7. If {b ₁ b ₂ b ₃ }={101}, the probability that the target group is 5 is P8. For details, see Table 2 below:

Table 2

target grouping	value	probability
{b 1 b 2 b 3 }={000}	0	P1
{b 1 b 2 b 3 }={001}	1	P2
{b 1 b 2 b 3 }={011}	3	P3
{b 1 b 2 b 3 }={111}	7	P4
{b 1 b 2 b 3 }={010}	2	P5
{b 1 b 2 b 3 }={100}	4	P6
{b 1 b 2 b 3 }={110}	6	P7
{b 1 b 2 b 3 }={101}	5	P8

It can be seen that the receiving device can obtain a plurality of joint soft information {s ₁ s ₂ … } for the information to be detected {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ …}, where the joint soft information s ₂ is a packet For the joint soft information of {b ₄ b ₅ b ₆ }, for the description of s ₂ , please refer to the above description of s ₁ of the target grouping {b ₁ b ₂ b ₃ }, and details are not repeated.

Combined with the above example 3, in the information to be detected {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ b ₇ b ₈ ... }, the target joint soft information of the target group {b ₁ b ₂ b ₃ b ₄ } It includes 2^4=16 values and the probability of each value. For details, please refer to the above description, which will not be repeated.

In the above example, the target joint soft information includes multiple values of the target group, and the probability of each value is used as an example for illustration. In other examples, the target joint soft information may also include the target The multiple values that the group has, and the logarithm of the ratio of the probabilities of two of the multiple values.

Continue to illustrate with the above example 1:

In the case where the target group is {b ₁ b ₂ }, if {b ₁ b ₂ }={00}, the probability that the target group is 0 is P1, and if {b ₁ b ₂ }={01}, the target The probability that the grouping value is 1 is P2. If {b ₁ b ₂ }={10}, the probability that the target grouping value is 2 is P3. If {b ₁ b ₂ }={11}, the target grouping value is P3. The probability of 3 is P4.

Specifically, the receiving device may predetermine the numerator of each probability ratio included in the target joint soft information of the target group {b ₁ b ₂ }, so that each probability included in the target joint soft information of the target group {b ₁ b ₂ } The numerator of the ratio is the same, and the FEC decoding module of the receiving device can determine the logarithm of the ratio of the probabilities of any two values included in the target group based on the target joint soft information.

For example, acquiring the target joint soft information s ₁ for the target group {b ₁ b ₂ } includes: L1, L2 and L3, where,

Step 205: The receiving device performs de-interleaving on the target joint soft information to obtain a de-interleaving sequence.

The execution body of this step is the de-interleaving module of the receiving device. For the specific description of the de-interleaving module, please refer to the embodiment shown in FIG. 1b, and details will not be repeated.

It can be seen that the de-interleaving module shown in this embodiment can de-interleave the joint soft information of each packet included in the information to be detected to obtain a de-interleaving sequence.

For example, in combination with the above example 1, when the information to be detected is {b ₁ b ₂ b ₃ b ₄ ......} and the divided groups are {b ₁ b ₂ }{b ₃ b ₄ } ...... , the de-interleaving module can de-interleave the joint soft information s ₁ of {b ₁ b ₂ } to form a de-interleaved symbol stream M1, and the de-interleaving module can also de-interleave the joint soft information s ₂ of {b ₃ b ₄ }. Interleaving to form the de-interleaved symbol stream M2, and so on, it can be known that the de-interleaving sequence is M1M2...

Step 206: The receiving device performs FEC decoding on the deinterleaved sequence to obtain the original signal of the target packet.

The execution subject shown in this step may be the FEC decoding module of the receiving device. For the specific description of the FEC decoding module, please refer to the embodiment shown in FIG. 1b, and details are not repeated.

Specifically, the de-interleaving module inputs the de-interleaving sequence to the FEC decoding module. The FEC decoding module shown in this embodiment is used to implement non-binary FEC decoding, and the FEC decoding module performs FEC decoding on the de-interleaving sequence to obtain the original target packet. Signal.

When the FEC decoding module is used to implement non-binary FEC decoding, it is effectively guaranteed that the FEC decoding module successfully decodes the target joint soft information.

It can be seen that when the FEC decoding module obtains the original signal of each packet of the information to be detected, the FEC decoding module can obtain the original signal of the information to be detected, so as to realize the decoding of the information to be detected.

The beneficial effects of this embodiment are described below:

In the process of decoding the information to be detected as shown in this embodiment, the information to be detected needs to be grouped, and each group includes symbols mapped to more than one constellation point, and the symbols included in the group are mapped to one or more constellations. point, transmit through two or more consecutive and mutually different time slots, so that multiple symbols included in each group are transmitted through at least two consecutive time slots in the channel. It can be seen that each packet transmits at least two consecutive time slots in the channel. Correlation between two consecutive time slots.

The receiving device performs de-interleaving processing on each packet, thereby effectively ensuring that the de-interleaving processing will not break up the correlation between at least two consecutive time slots in the channel transmitted by each packet, effectively avoiding the need for help. Loss of decoded valid information, the valid information is used to indicate the correlation between at least two consecutive time slots in the channel, it can be seen that the accuracy of decoding the information to be detected is improved, and the sequence detection module is effectively improved. Each group was subjected to sequence detection to suppress the effects of ISI damage.

In this embodiment, more information is transmitted to the FEC decoding module. For example, for the group {b ₁ b ₂ }, if the existing scheme is adopted, the FEC decoding module needs to transmit two probability values, that is, the symbol b ₁ The probability value and the probability value of the symbol b ₂ , and the method shown in this embodiment, as shown in Table 1, needs to transmit at least three probability values to the FEC decoding module for the group {b ₁ b ₂ }, so as to improve the decoding performance. bring greater performance gains.

Each packet shown in this embodiment transmits the correlation between at least two consecutive time slots in the channel, so that the packet can be decoded accurately without repeated iteration, and the complexity and efficiency of the decoding process are reduced.

Another embodiment of the decoding method provided by the present application will be described below with reference to FIG. 3 , wherein FIG. 3 is a flowchart of the steps of the second embodiment of the decoding method provided by the present application.

First, the premise of executing the method shown in this embodiment is described:

Two or more adjacent symbols in the information to be detected shown in this example are mapped to the same constellation point, and the constellation point is transmitted through the same time slot. It can be seen that it is difficult for the receiving device to decode two or more symbols transmitted through the same time slot.

Compared with the embodiment shown in FIG. 2 , the method shown in this embodiment can also reduce the complexity of the decoding process of the FEC decoding module and effectively improve the decoding efficiency when the ISI damage can be effectively suppressed. The specific execution process is as follows Show:

Step 301: The receiving device receives an optical signal from the transmitting device.

Step 302: The receiving device converts the optical signal to obtain the information to be detected.

For the description of the specific execution process of steps 301 to 302 shown in this embodiment, please refer to steps 201 to 202 shown in FIG. 2 for details, and the specific execution process will not be repeated.

Step 303: The receiving device divides the information to be detected to form a plurality of first groups.

For the process of dividing the information to be detected by the receiving device shown in this embodiment to form multiple first groups, please refer to the process of dividing the information to be detected by the receiving device shown in step 203 shown in FIG. 2 to form multiple groups, Details are not described in this embodiment.

Step 304: The receiving device divides the first group into a plurality of second groups.

The execution body of this step is the sequence detection module of the receiving device. For the specific description of the sequence detection module, please refer to the embodiment shown in FIG. 1 b , which will not be described in detail.

This embodiment does not limit the number of symbols included in the second group, as long as the multiple symbols included in each second group are mapped to at least one constellation point included in the constellation diagram of the optical signal, and the at least one constellation point It is sufficient to perform transmission through at least two consecutive and mutually different time slots.

Optionally, the receiving device may evenly divide multiple symbols included in the first group into multiple second groups. For example, if the first group includes M symbols, after dividing the first group into two second groups, In this case, each second group includes M/2 symbols, and the M/2 symbols are mapped to at least one constellation point included in the constellation diagram of the optical signal, and the at least one constellation point passes through at least two consecutive and Different time slots are used for transmission. In other examples, the number of symbols included in each second group divided by the first group may also be unequal.

For better understanding, an exemplary description is given below in conjunction with Example 3 in the embodiment shown in FIG. 2 as an example:

It can be seen from the above example 3 that the information to be detected is {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ b ₇ b ₈ ... }, and the GF of the FEC decoding module is GF(2^4), it can be known that Each first group includes 4 symbols. Specifically, the first first group divided by grouping the to-be-detected information {b ₁ b ₂ b ₃ b ₄ b ₅ b ₆ b ₇ b ₈ ...} is { b ₁ b ₂ b ₃ b ₄ }, the second first grouping is {b ₅ b ₆ b ₇ b ₈ }, and so on.

In this example, every two symbols are mapped to one constellation point. It can be known that the symbol b ₁ b ₂ in the first first group {b ₁ b ₂ b ₃ b ₄ } is mapped to the first constellation point, and the symbol b ₃ b ₄ is mapped to a second constellation point, and the first constellation point and the second constellation point may be the same or different, which is not specifically limited in this example.

The receiving device divides the second group on the basis of each divided first group:

The following specifically takes the first group {b ₁ b ₂ b ₃ b ₄ } as an example for illustrative description:

The first packet {b ₁ b ₂ b ₃ b ₄ } shown in this example is capable of transmitting the correlation between two consecutive time slots in the channel (ie the time slot used to transmit the first constellation point and the time slot used to transmit the first constellation point The time slot of two constellation points, and the time slot used for transmitting the first constellation point and the time slot used for transmitting the second constellation point are adjacent at the transmission time), the divided second group also needs two transmission channels in the channel. correlation between consecutive time slots, for this purpose, the second grouping is required to include one symbol in {b ₁ b ₂ }, the second grouping is also required to include one symbol in {b ₃ b ₄ }, the second Please refer to Table 3 for details of the grouping method:

table 3

The division method of the second group 1	{b 1 b 3 }{b 2 b 4 }
The division method of the second group 2	{b 1 b 4 }{b 2 b 3 }

As shown in Table 3, there are two ways to divide the first group {b ₁ b ₂ b ₃ b ₄ } into two second groups, and the receiving device can use any method to divide the first group into two groups. a second group.

In the case of dividing a first packet into two second packets, the number of symbols included in the second packet is smaller than the number of symbols included in the first packet, and the second packet can also transmit two different and continuous time The correlation between the slots (ie, the time slot used to transmit the first constellation point and the time slot used to transmit the second constellation point).

Optionally, in the process of dividing the first group into a plurality of second groups, the division method of the second group may also be selected based on the correlation. In the division mode, the division mode with the greatest correlation of the second group is selected for division, thereby improving the correlation between different and consecutive time slots transmitted by the divided second group.

Continuing to refer to the above example, because this example takes the optical signal as PAM4 as an example, and the coding method used by PAM4 is Gray coding, it can be seen that the correlation transmitted by the above-mentioned division method 1 of the second grouping is greater than that of the above-mentioned division method 2. For the correlation of transmission, the receiving device can use the above-mentioned second grouping method 1 to divide the second group.

Step 305: The receiving device acquires the target joint soft information corresponding to the target second group.

The target second group shown in this embodiment is any second group in any first group included in the information to be detected.

For the description of the execution process of acquiring the target joint soft information shown in step 305 shown in this embodiment, please refer to the process shown in step 204 shown in FIG. will not go into details.

Step 306: The receiving device performs de-interleaving on the target joint soft information to obtain a de-interleaving sequence.

Step 307: The receiving device performs FEC decoding on the de-interleaved sequence to obtain the original signal of the target second packet.

For the specific execution process of step 306 to step 307 shown in this embodiment, please refer to the execution process of step 205 to step 206 shown in FIG. 2 , and details are not repeated.

With the method shown in this embodiment, since the number of symbols included in the second group is smaller than the number of symbols included in the first group, in the process of decoding each second group by the FEC decoding module, the FEC decoding module can be effectively reduced. the decoding difficulty and improve the decoding efficiency.

For better understanding, continue to refer to the above example, in the case where the first packet is {b ₁ b ₂ b ₃ b ₄ }, the GF of the FEC decoding module is GF(2^4), and in the FEC decoding When the module decodes the second packet {b ₁ b ₃ }{b ₂ b ₄ }, the decoding can be realized when the GF of the FEC decoding module is GF(2^2). It can be seen that the FEC decoding module decodes the second packet The order of the required GF is smaller than the order of the GF required by the FEC decoding module to decode the first packet, thereby reducing the decoding difficulty of the FEC decoding module.

For the description of the beneficial effects of the method shown in this embodiment, reference may also be made to FIG. 2 , which will not be repeated in this embodiment.

The following embodiment provides a decoding method that can effectively improve decoding accuracy. In order to better understand the method shown in this embodiment, the following first combines the receiving equipment shown in FIG. 4 to the method shown in this embodiment. The structure is explained:

As shown in FIG. 4, the receiving device 400 includes a local laser 125, a polarization multiplexing coherent front end 126, four analog-to-digital converters (ie analog-to-digital converters 127, 128, 129 and 130), two dispersion compensation modules (ie Dispersion compensation modules 131 and 132), polarization compensation module 133, two phase recovery modules (ie phase recovery modules 134 and 135), four post-filter modules (ie, post-filter modules 136, 137, 138 and 139), four There are sequence detection modules (ie sequence detection modules 140, 141, 142 and 143), a de-interleaving module 145 and an FEC decoding module 144. For a detailed description of the above structures, please refer to FIG. 1b, which will not be repeated.

Compared with the embodiment shown in FIG. 1b, the receiving device shown in this embodiment further includes an interleaving module 401, the interleaving module 401 is connected between the FEC decoding module 144 and each sequence detection module, and the interleaving module 401 is used to The symbol stream from the FEC decoding module 144 is interleaved and transmitted to the corresponding sequence detection module to iterate the joint soft information to improve the accuracy of the joint soft information transmitted by the sequence detection module to the FEC decoding module, thereby improving the The accuracy of FEC decoding module decoding based on joint soft information is obtained.

Based on the receiving device shown in FIG. 4 , another embodiment of the decoding method provided by the present application is described below with reference to FIG. 5 :

In the method shown in this embodiment, the receiving device can decode the information to be detected based on a turbo code iteration. Specifically, the receiving device repeatedly iterates the information to be detected between the sequence detection module and the FEC decoding module to achieve accurate decoding of the information to be detected. The specific process is as follows:

Step 501: The receiving device receives an optical signal from the transmitting device.

Step 502: The receiving device converts the optical signal to obtain the information to be detected.

Step 503: The receiving device divides the information to be detected to form multiple groups.

For the description of the specific execution process of step 501 to step 503 shown in this embodiment, please refer to the description of the process shown in step 201 to step 203 shown in FIG. 2 for details, and details are not repeated.

Step 504: The receiving device acquires the first target joint soft information corresponding to the target group.

For the process of receiving and acquiring the first target joint soft information shown in this embodiment, please refer to the process of the receiving device acquiring the target joint soft information shown in step 204 shown in FIG. 2 , and details are not repeated in this embodiment.

Step 505: The receiving device performs de-interleaving on the first target joint soft information to obtain a first de-interleaving sequence.

For the specific process of acquiring the first de-interleaving sequence by the receiving device shown in this embodiment, please refer to the process of acquiring the de-interleaving sequence by the receiving device shown in step 205 in FIG. 2 , which is not repeated in this embodiment.

Step 506: The receiving device performs FEC decoding on the first deinterleaved sequence corresponding to the target packet to obtain the original signal of the target packet and the joint soft information after the first FEC decoding.

In this embodiment, when the FEC decoding module receives the first target joint soft information corresponding to the target group output from the sequence detection module, it can perform FEC decoding on the first target joint soft information corresponding to the target group to obtain Joint soft information after first FEC decoding.

Continuing with the above example 1, in the case where the target packet is {b ₁ b ₂ }, and the target packet comes from the sequence detection module 140, the de-interleaving module performs the first step corresponding to the target packet {b ₁ b ₂ }. After the target joint soft information is de-interleaved, it is transmitted to the FEC decoding module, and the FEC decoding module can perform FEC decoding on the first target joint soft information corresponding to the target group {b ₁ b ₂ } to obtain the joint soft information after the first FEC decoding. .

Step 507: The receiving device interleaves the joint soft information after the first FEC decoding to obtain a first interleaving sequence.

In this embodiment, in order to enable the sequence detection module to iteratively detect the joint soft information multiple times, so as to improve the accuracy of decoding, the FEC decoding module receives the first target joint soft information from the sequence detection module and In the case of the first FEC decoded joint soft information generated by the FEC decoding module itself, the FEC decoding module only sends the first FEC decoded joint soft information to the sequence detection module.

Optionally, in order to improve the accuracy of sequence detection performed by the sequence detection module on the joint soft information after decoding the first FEC, the FEC decoding module transmits the joint soft information after decoding the first FEC to the interleaving module, and the interleaving module performs the joint soft information decoding on the first FEC. After FEC decoding, the joint soft information is interleaved to generate the first interleaving sequence. The interleaving module can transmit the first interleaving sequence to the corresponding sequence detection module. For example, the first target joint soft information in the target packet comes from the sequence detection module. module 140, the interleaving module transmits the first interleaving sequence to the sequence detecting module 140, and the sequence detecting module 140 performs sequence detection on the first interleaving sequence of the target packet again.

Step 508: The receiving device performs sequence detection on the first interleaved sequence to obtain the second target joint soft information.

When the sequence detection module receives the first interleaving sequence from the interleaving module, the sequence detection module can perform sequence detection on the first interleaving sequence to obtain the second target joint soft information of the target packet.

Step 509: The receiving device performs de-interleaving on the second target joint soft information to obtain a second de-interleaving sequence.

For the process of obtaining the second de-interleaving sequence by the receiving device shown in this step, please refer to the process of obtaining the first de-interleaving sequence by the receiving device shown in the above step 505, and details are not repeated.

Step 510: The receiving device performs FEC decoding on the second deinterleaved sequence corresponding to the target packet to obtain the original signal of the target packet and the joint soft information after the second FEC decoding.

For the process of obtaining the joint soft information after the second FEC decoding by the receiving device shown in this step, please refer to the process of the receiving device obtaining the joint soft information after the first FEC decoding shown in step 506, and details are not repeated.

It can be seen that, in this embodiment, the FEC decoding module repeatedly performs FEC decoding on the joint soft information of the target packet from the sequence detection module, thereby improving the accuracy of the original signal of the target packet decoded by the FEC decoding module.

Specifically, if the FEC decoding module determines that it is necessary to perform sequence detection on the joint soft information corresponding to the target group again, the FEC decoding module sends the second FEC-decoded joint soft information to the sequence detection module again, so that the sequence detection module can detect the target group again. The joint soft information corresponding to the group is subjected to sequence detection again. For the description of the specific process, please refer to the steps 507 to 509 above.

It should be clear that, if the accuracy of the joint soft information of the target grouping obtained by the FEC decoding module is higher, the more accurate the decoding of the target grouping by the FEC decoding module can be guaranteed. Repeated sequence detection is performed on the joint soft information of the grouping, thereby improving the accuracy of the joint soft information of the target grouping obtained by the FEC decoding module.

If the FEC decoding module determines that it is not necessary to perform sequence detection on the joint soft information corresponding to the target group again, the original signal of the target group obtained by the FEC decoding this time is obtained to realize the decoding of the target group.

This embodiment does not limit the number of iterations of the joint soft information of the target group. For the description of the process of each iteration, please refer to the above-mentioned iterative process of detecting joint soft information in the second sequence, and details are not repeated.

For the description of the beneficial effects of the method shown in this embodiment, please refer to the embodiment shown in FIG. 2 .

Because the method shown in this embodiment is adopted, the joint soft information corresponding to the target group can be iterated, thereby effectively improving the decoding accuracy of the information to be detected, and effectively improving the system performance.

In this embodiment, due to the process of iterating the joint soft information of the target group each time, more information is transmitted. For example, for the group {b ₁ b ₂ }, if the existing scheme is adopted, it needs to be Two probability values are transmitted, that is, the soft information of the symbol b ₁ and the soft information of the symbol b ₂ , and the method shown in this embodiment is adopted, as shown in Table 1, for the joint soft information iteration of the group {b ₁ b ₂ } In the process, at least three probability values need to be transmitted, which effectively ensures the accuracy of the joint soft information output by the sequence detection module, and brings greater performance benefits to the iterative performance, and solves the system cost caused by turbo convergence. .

The structure of the receiving device is described from the perspective of functional modules as shown in FIG. 1 b and FIG. 4 , and the structure of the receiving device is described below in conjunction with FIG. 6 from the perspective of physical hardware, wherein FIG. 6 is provided by this application. A structural example diagram of the third embodiment of the receiving device.

The receiving device includes a processor 602 , a memory 603 and a receiver 601 . The processor 602, the memory 603 and the receiver 601 are interconnected by wires. Among them, the memory 603 is used for storing program instructions and data. It should be noted that the receiving device may be a receiving device that implements the decoding methods in the embodiments shown in FIG. 2 , FIG. 3 , and FIG. 5 .

In a possible implementation manner, the memory 603 stores program instructions and data supporting the steps shown in FIG. 2 , the receiver 601 is used to execute the step 201 shown in FIG. 2 , and the processor 602 is used to execute the steps shown in FIG. 2 . Steps 202 to 206 .

In a possible implementation manner, the memory 603 stores program instructions and data supporting the steps shown in FIG. 3 , the receiver 601 is used to execute the step 301 shown in FIG. 3 , and the processor 602 is used to execute the steps shown in FIG. 3 . Step 302 to Step 307 .

In a possible implementation manner, the memory 603 stores program instructions and data supporting the steps shown in FIG. 5 , the receiver 601 is used to execute the step 501 shown in FIG. 5 , and the processor 602 is used to execute the steps shown in FIG. 5 . Step 502 to Step 511.

The embodiment of the present application also provides a chip. The chip integrates circuits and one or more interfaces for implementing the functions of the above-mentioned processor 602 . When a memory is integrated in the chip, the chip can perform the method steps of any one or more of the foregoing embodiments. When the memory is not integrated in the chip, it can be connected with the external memory through the interface. The chip implements the actions performed by the receiving device in the above embodiment according to the program codes stored in the external memory.

Those of ordinary skill in the art can understand that all or part of the steps of implementing the above embodiments can be completed by hardware, or can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. The storage medium can be read only memory, random access memory, etc. Specifically, for example, the above-mentioned processing unit or processor may be a central processing unit, a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate Array (field programmable gate array, FPGA) or other programmable logic device, transistor logic device, hardware component or any combination thereof. Whether the above functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of this application.

When implemented in software, the method steps described in the above embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the procedures or functions according to the embodiments of the present application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions may be stored on or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted over a wire from a website site, computer, server or data center (eg coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (eg infrared, wireless, microwave, etc.) means to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that includes one or more available media integrated.

Finally, it should be noted that the above is only the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any changes or substitutions should be included within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims (18)

1. A decoding method, characterized in that the method comprises:

   The receiving device converts the received optical signal to obtain information to be detected, the information to be detected includes a plurality of groups, each of the groups includes a plurality of symbols, and the plurality of symbols are mapped to the constellation of the optical signal. On the included at least one constellation point, the at least one constellation point is transmitted through at least two consecutive time slots;

   The receiving device acquires target joint soft information corresponding to the target group, where the target joint soft information is used to indicate various values of the target group, and the target group is one of the multiple groups;

   The receiving device performs forward error correction (FEC) decoding on the target joint soft information to obtain the original signal of the target packet.
2. The method according to claim 1, wherein after the receiving device acquires the target joint soft information corresponding to the target group, the method further comprises:

   The receiving device de-interleaves the target joint soft information to obtain a de-interleaving sequence;

   The receiving device performs forward error correction (FEC) decoding on the target joint soft information to obtain the original signal of the target packet, including:

   The receiving device performs FEC decoding on the deinterleaved sequence to obtain the original signal of the target packet.
3. The method according to claim 1 or 2, wherein the acquiring, by the receiving device, the target joint soft information corresponding to the target group comprises:

   The receiving device performs sequence detection on the target packet to obtain the target joint soft information.
4. The method according to any one of claims 1 to 3, wherein the obtaining, by the receiving device, the target joint soft information corresponding to the target group comprises:

   The receiving device performs FEC decoding on the joint soft information corresponding to the target group to obtain the joint soft information after FEC decoding;

   The receiving device performs sequence detection on the joint soft information after FEC decoding to obtain the target joint soft information.
5. The method according to claim 4, wherein the receiving device performs sequence detection on the joint soft information after FEC decoding to obtain the target joint soft information comprising:

   The receiving device interleaves the joint soft information after the FEC decoding to obtain an interleaving sequence;

   The receiving device performs sequence detection on the interleaved sequence to obtain the target joint soft information.
6. The method according to any one of claims 1 to 5, wherein before the receiving device converts the received optical signal to obtain the information to be detected, the method further comprises:

   The receiving device determines at least one first symbol and at least one second symbol included in the information to be detected, wherein the at least one first symbol is mapped to a first constellation point, and the at least one second symbol is mapped to to the second constellation point, the at least one first symbol and the at least one second symbol are adjacent in the information to be detected;

   The receiving device divides at least part of the at least one first symbol and at least part of the second symbol of the at least one second symbol into the target group.
7. The method according to any one of claims 1 to 6, wherein the target joint soft information includes multiple values of the target group, and a value of any one of the multiple values. probability.
8. The method according to any one of claims 1 to 6, wherein the target joint soft information comprises any two values among multiple values possessed by the target group, and the two values The logarithm of the ratio of the probabilities.
9. A receiving device, characterized in that the receiving device comprises:

   The conversion module is used for converting the received optical signal to obtain the information to be detected, the information to be detected includes a plurality of groups, each of the groups includes a plurality of symbols, and the plurality of symbols are mapped to the optical signal. On at least one constellation point included in the constellation diagram, the at least one constellation point is transmitted through at least two consecutive time slots;

   A sequence detection module, configured to acquire target joint soft information corresponding to a target grouping, the target joint soft information is used to indicate various values of the target grouping, and the target grouping is one of the multiple groups ;

   A forward error correction FEC decoding module, configured to perform forward error correction FEC decoding on the target joint soft information to obtain the original signal of the target packet.
10. The receiving device according to claim 9, wherein the receiving device further comprises a de-interleaving module, and the de-interleaving module is configured to perform de-interleaving on the target joint soft information to obtain a de-interleaving sequence;

    The FEC decoding module is further configured to perform FEC decoding on the deinterleaved sequence to obtain the original signal of the target packet.
11. The receiving device according to claim 9 or 10, wherein the sequence detection module is specifically configured to perform sequence detection on the target packet to obtain the target joint soft information.
12. The receiving device according to claim 9 or 10, characterized in that:

    The FEC decoding module is further configured to perform FEC decoding on the joint soft information corresponding to the target grouping to obtain joint soft information after FEC decoding;

    The sequence detection module is further configured to perform sequence detection on the joint soft information after FEC decoding to obtain the target joint soft information.
13. The receiving device according to claim 12, wherein the receiving device further comprises an interleaving module, and the interleaving module is configured to interleave the joint soft information after the FEC decoding to obtain an interleaving sequence;

    The sequence detection module is further configured to perform sequence detection on the interleaved sequence to obtain the target joint soft information.
14. The receiving device according to any one of claims 9 to 13, wherein the sequence detection module is further configured to:

    Determine at least one first symbol and at least one second symbol included in the information to be detected, wherein the at least one first symbol is mapped to a first constellation point, and the at least one second symbol is mapped to a second constellation point, the at least one first symbol and the at least one second symbol are located adjacent to each other in the information to be detected;

    Dividing at least a portion of the at least one first symbol and at least a portion of the at least one second symbol into the target packet.
15. The receiving device according to any one of claims 9 to 14, wherein the target joint soft information comprises multiple values of the target packet, and any value of the multiple values The probability.
16. The receiving device according to any one of claims 9 to 14, wherein the target joint soft information comprises any two values of multiple values possessed by the target group, and the two values The logarithm of the ratio of the probabilities of the value.
17. A receiving device, characterized in that it includes a processor, a memory and a receiver, and the processor is respectively interconnected with the memory and the receiver through a line;

    The receiver is configured to receive an optical signal from a transmitting device, and the processor is configured to invoke program codes in the memory to execute the method of any one of claims 1 to 8.
18. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program, and when the computer program is executed by hardware, is used to execute the method shown in any one of claims 1 to 8 .

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