Frequency offset estimation method and device

Abstract

The embodiment of the invention provides a frequency offset estimation method, which is applied to a receiving device, and by using the method, frequency offset estimation in a relatively large frequency offset range can be realized based on a second pilot symbol in a second signal received by the receiving device. The frequency offset range may be divided into a plurality of consecutive frequency offset segments, and the plurality of consecutive frequency offset segments may include a first frequency offset segment. Specifically, the receiving device can receive a second signal, the second signal comprises a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted. After the receiving device obtains the second signal, the first frequency offset estimation value corresponding to the second signal in the first frequency offset section can be determined firstly, and then the frequency offset estimation value of the second signal is determined according to the first frequency offset estimation value, so that the frequency offset estimation in the frequency offset range is realized.

Description

Technical Field

[0001] The present application relates to the field of communications, and in particular to a method and device for estimating a frequency offset. Background Art

[0002] In a coherent optical communication system, due to the wavelength drift and jitter of the signal light source and the local oscillator light source, the signal received by the receiving device will have a frequency offset, and the signal offset will affect the recovery of the received signal by the receiving device. Therefore, it is particularly important to determine the frequency offset of the signal received by the receiving device. Among them, the signal light source can be a transmitting laser at the transmitting end, and the local oscillator light source can be a local laser at the receiving end.

[0003] In some scenarios, the data frame sent by the sending device to the receiving device may include a training sequence and a pilot symbol. The receiving device may determine the frequency offset of the received signal based on the training sequence and the pilot symbol in the received signal, thereby performing signal recovery on the received signal. However, with the development of communication technology, the structure of the data frame has also changed accordingly. In some scenarios, the data frame no longer includes the aforementioned training sequence.

[0004] When the data frame no longer includes a training sequence, how the receiving device determines the frequency offset of the received signal is a problem that urgently needs to be solved. Summary of the invention

[0005] The embodiment of the present application provides a method for estimating a frequency offset, which can accurately determine the frequency offset of a signal received by a receiving device based on a pilot symbol in the signal received by the receiving device.

[0006] In a first aspect, an embodiment of the present application provides a method for estimating a frequency offset, which can be applied to a receiving device. By using this method, a frequency offset estimation within a frequency offset range can be implemented based on a second pilot symbol in a second signal received by the receiving device. The frequency offset range can be a larger frequency offset estimation range. When performing frequency offset estimation, the aforementioned frequency offset range can be divided into a plurality of continuous frequency offset segments, and the plurality of continuous frequency offset segments can include a first frequency offset segment. Specifically, the receiving device can receive a second signal, the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted. After the receiving device obtains the second signal, the frequency offset estimation value of the second signal can be determined. When determining the frequency offset estimation value of the second signal, the receiving device does not directly determine the frequency offset estimation value of the second signal within the aforementioned frequency offset range, but first determines the first frequency offset estimation value corresponding to the second signal in the first frequency offset segment, and then determines the frequency offset estimation value of the second signal according to the first frequency offset estimation value. The span of the first frequency offset segment is smaller than the span of the frequency offset range, and the first frequency offset estimation value can be estimated more accurately based on the second pilot symbol. Correspondingly, based on the first frequency offset estimation value, the frequency offset estimation value of the second signal can also be accurately determined. It can be seen that, using the solution of the embodiment of the present application, the receiving device can achieve frequency offset estimation within the frequency offset range based on the second pilot symbol in the received second signal.

[0007] In a possible implementation, the first frequency offset estimation value of the second signal in the first frequency offset segment can be determined by two parts. One part is "a certain frequency offset value", and the other part is the jitter frequency offset jittering near the "certain frequency offset value". As a specific example, the aforementioned "certain frequency offset value" can be a preset frequency offset lock value corresponding to the first frequency offset segment, and the aforementioned jitter frequency offset can be a target jitter frequency offset. In this case, based on the second pilot symbol, the first frequency offset estimation value corresponding to the second signal in the first frequency offset segment is determined. In specific implementation, the second pilot symbol can be firstly frequency compensated according to the preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol. Then, according to the phase difference between the first compensated pilot symbol and the first pilot symbol, the target jitter frequency offset is determined, the first signal includes the first pilot symbol, and the second pilot symbol is the symbol received by the receiving device after the first pilot symbol is transmitted; after determining the target jitter frequency offset, the first frequency offset estimation value can be determined according to the target jitter frequency offset and the preset offset lock value. For example, the sum of the target jitter frequency offset and the preset offset lock value may be determined as the first frequency offset estimate. It can be seen that, using the solution of the embodiment of the present application, although there is no training sequence in the second signal, when calculating the first frequency offset estimate, it can be calculated based on the preset frequency offset lock value, so that even if there is no training sequence in the second signal, the first frequency offset estimate corresponding to the second signal in the first frequency offset segment can be calculated.

[0008] In a possible implementation, considering that the jitter frequency offset range that can be determined based on the second pilot symbol is a range that is symmetrical relative to 0, in one example, the preset frequency offset lock value may be the center frequency of the first frequency offset segment. In other words, the first frequency offset segment is symmetrical relative to the preset frequency offset lock value, so that within the first frequency offset segment, the target jitter frequency offset can be accurately estimated based on the second pilot symbol.

[0009] In a possible implementation, the second signal may include multiple second pilot symbols. Therefore, in a specific implementation, "performing frequency compensation on the second pilot symbol according to the preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol" can perform frequency compensation on each of the multiple second pilot symbols according to the preset frequency offset lock value to obtain a first compensated pilot symbol corresponding to each second pilot symbol, so as to facilitate the subsequent determination of the target jitter frequency offset based on the first compensated pilot symbol corresponding to each second pilot symbol, thereby accurately determining the target jitter frequency offset.

[0010] In a possible implementation, "determining the target jitter frequency offset based on the first compensation pilot symbol corresponding to each second pilot symbol" can be implemented in detail by obtaining the phase difference corresponding to each first compensation pilot symbol according to the first compensation pilot symbol corresponding to each second pilot symbol and each first pilot symbol. Then, the jitter frequency offset corresponding to each first compensation pilot symbol is determined according to the phase difference corresponding to each first compensation pilot symbol. Furthermore, the target jitter frequency offset is determined based on the jitter frequency offset corresponding to each first compensation pilot symbol.

[0011] In a possible implementation, the frequency offset estimation value of the first signal is determined according to the first frequency offset estimation value. In a specific implementation, for example, the corresponding first frequency offset estimation value can be calculated for at least one first frequency offset segment in the aforementioned multiple continuous frequency offset segments. Then, according to the accuracy of the first frequency offset estimation value corresponding to at least one first frequency offset segment, the first frequency offset estimation value with the highest accuracy is selected from the first frequency offset estimation value corresponding to at least one first frequency offset segment as the frequency offset estimation value of the second signal. In a specific example, the accuracy of the first frequency offset estimation value can be determined based on the phase difference generated by the second pilot symbol obtained by the first frequency offset estimation value during the transmission process. For a certain first frequency offset estimation value, if the phase difference generated by the second pilot symbol determined based on the first frequency offset estimation value during the transmission process is smaller, it means that the first frequency offset estimation value is more accurate. Therefore, the phase difference generated by the first pilot symbol during the transmission process can be determined based on the first frequency offset estimation value corresponding to each first frequency offset segment, and then the first frequency offset estimation value corresponding to the first frequency offset segment with the smallest phase difference is determined as the frequency offset estimation value of the second signal.

[0012] In a possible implementation, the frequency offset range may be divided in an average division manner, in which case the spans of the various frequency offset segments are the same. In this manner, the division is simpler.

[0013] In one possible implementation, the aforementioned frequency offset range is a larger frequency offset range, which is larger than the jitter frequency offset range that can be determined based on the second pilot symbol. In addition, in order to enable the first frequency offset estimate to be accurately determined based on the second pilot symbol within the first frequency offset segment, the frequency span corresponding to each frequency offset segment in the multiple continuous frequency offset segments is less than or equal to the frequency span of the jitter frequency offset range. Among them, for a certain frequency offset segment, the frequency span corresponding to the frequency offset segment is the difference between the maximum frequency and the minimum frequency corresponding to the frequency offset segment. Similarly, the frequency span of the jitter frequency offset range is the difference between the maximum frequency and the minimum frequency of the jitter frequency offset range.

[0014] In a possible implementation, the frequency offset range mentioned in the embodiment of the present application is the frequency offset range between the received carrier and the carrier of the laser of the receiving device. The received carrier refers to the carrier received by the receiving device, and the laser of the receiving device may be a local laser of the receiving end. In one example, the receiving end may be a communication device including the receiving device.

[0015] In a possible implementation, after determining the frequency offset estimate of the second signal, frequency compensation may be performed on data symbols in the second signal, so as to restore data sent by the sending device based on the frequency compensated data symbols.

[0016] In the second aspect, an embodiment of the present application provides a receiving device, which includes: an acquisition unit, used to acquire a second signal, the second signal including a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; a processing unit, used to determine, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, the first frequency offset segment being a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing the frequency offset range; and determine the frequency offset estimate of the second signal according to the first frequency offset estimate.

[0017] In a possible implementation, the receiving device may be an optical module. In other words, the optical module may include the aforementioned acquisition unit and processing unit.

[0018] In a possible implementation, the receiving device may be a physical layer (PHY) chip. In other words, the PHY chip may include the aforementioned acquisition unit and processing unit.

[0019] In one possible implementation, the processing unit is used to: perform frequency compensation on the second pilot symbol according to a preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol; determine a target jitter frequency offset according to a phase difference between the first compensated pilot symbol and the first pilot symbol, wherein the first signal includes the first pilot symbol, and the second pilot symbol is a symbol received by a receiving device after the first pilot symbol is transmitted; determine the first frequency offset estimate value according to the target jitter frequency offset and the preset offset lock value.

[0020] In a possible implementation manner, the preset frequency offset locking value corresponding to the first frequency offset segment is the center frequency of the first frequency offset segment.

[0021] In one possible implementation, the second signal includes multiple second pilot symbols, and the second pilot symbols are frequency compensated according to a preset frequency offset locking value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol, including: frequency compensating each second pilot symbol among the multiple second pilot symbols according to the preset frequency offset locking value to obtain a first compensated pilot symbol corresponding to each second pilot symbol.

[0022] In a possible implementation, determining the target jitter frequency offset based on the phase difference between the first compensation pilot symbol and the first pilot symbol includes: obtaining the phase difference corresponding to each first compensation pilot symbol based on the first compensation pilot symbol corresponding to each second pilot symbol and each first pilot symbol; determining the jitter frequency offset corresponding to each first compensation pilot symbol based on the phase difference corresponding to each first compensation pilot symbol; and determining the target jitter frequency offset based on the jitter frequency offset corresponding to each first compensation pilot symbol.

[0023] In one possible implementation, the processing unit is used to: determine the phase difference generated by the first pilot symbol during the transmission process based on the first frequency offset estimation value corresponding to each of the first frequency offset segments; and determine the first frequency offset estimation value corresponding to the first frequency offset segment with the smallest phase difference as the frequency offset estimation value of the second signal.

[0024] In a possible implementation manner, the multiple continuous frequency offset segments are obtained by dividing the frequency offset range in an even division manner.

[0025] In one possible implementation, the frequency offset range is larger than a jitter frequency offset range that can be determined based on the second pilot symbol, and the frequency span corresponding to each frequency offset segment in the multiple continuous frequency offset segments is less than or equal to the frequency span of the jitter frequency offset range.

[0026] In a possible implementation manner, the frequency offset range is a frequency offset range between a received carrier and a carrier of a laser of the receiving device.

[0027] In a possible implementation manner, the processing unit is further configured to: perform frequency compensation on data symbols in the second signal based on a frequency offset estimate of the second signal.

[0028] In a third aspect, an embodiment of the present application provides an integrated circuit, comprising: an interface circuit for acquiring a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by a receiving device after a first signal sent by a sending device is transmitted; a processing circuit for determining, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, wherein the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; and determining a frequency offset estimate of the second signal according to the first frequency offset estimate.

[0029] Regarding the specific implementation of the processing circuit determining the first frequency offset estimation value corresponding to the second signal in the first frequency offset segment based on the second pilot symbol, reference may be made to the above-mentioned relevant description of the frequency offset estimation method in the first aspect and any item of the first aspect, and no repeated description will be made here.

[0030] In a fourth aspect, an embodiment of the present application provides a communication system, comprising: a sending device and a receiving device; the sending device is used to send a first signal to the receiving device; the receiving device is used to obtain a second signal, the second signal including a second pilot symbol, the second signal being a signal received by the receiving device after the first signal sent by the sending device is transmitted; based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal within a first frequency offset segment is determined, the first frequency offset segment being a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; based on the first frequency offset estimate, a frequency offset estimate of the second signal is determined.

[0031] Regarding the specific implementation of the receiving device determining the first frequency offset estimation value corresponding to the second signal in the first frequency offset segment based on the second pilot symbol, reference may be made to the above relevant description of the frequency offset estimation method in the first aspect and any item of the first aspect, and no repeated description will be made here.

[0032] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, including instructions or a computer program, which, when executed on a computer, enables the computer to execute any of the methods described in the first aspect above.

[0033] In a sixth aspect, an embodiment of the present application provides a computer program product comprising instructions or a computer program, which, when executed on a computer, enables the computer to execute any of the methods described in the first aspect above. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 is an architectural diagram of a coherent transmission system;

[0036] Figure 2a It is a structural diagram of a data frame;

[0037] Figure 2b It is a structural diagram of another data frame;

[0038] Figure 3 A schematic diagram of a flow chart of a frequency offset estimation method provided in an embodiment of the present application;

[0039] Figure 4 A schematic diagram of a frequency offset segment provided in an embodiment of the present application;

[0040] Figure 5 A schematic diagram of a flow chart of another frequency offset estimation method provided in an embodiment of the present application;

[0041] Figure 6 A schematic diagram of a flow chart of another frequency offset estimation method provided in an embodiment of the present application;

[0042] Figure 7 A schematic diagram of a flow chart of another frequency offset estimation method provided in an embodiment of the present application;

[0043] Figure 8A schematic diagram of the structure of a receiving device provided in an embodiment of the present application;

[0044] Fig. 9 A schematic diagram of the structure of an integrated circuit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The embodiment of the present application provides a method for estimating a frequency offset, which can accurately determine the frequency offset of a signal received by a receiving device based on a pilot symbol in the signal received by the receiving device.

[0046] See also Figure 1 , Figure 1 An architectural diagram of a coherent transmission system is shown.

[0047] like Figure 1 As shown, the transmitting end includes a transmitting laser and a coherent transmitter. The transmitting end can modulate the data to be transmitted to obtain multiple electrical signals. For example, 4 pulse amplitude modulation (4Pulse Amplitude Modulation, PAM4) is used to modulate the data to be transmitted to obtain 4 electrical signals. Then, the at least one electrical signal is processed by the transmitting laser and the coherent transmitter to obtain an optical signal. The optical signal is transmitted to the receiving end through the optical fiber.

[0048] The receiving end includes a coherent receiver, a local laser and a digital signal processing (DSP) module. After the optical signal sent by the transmitting end is transmitted to the receiving end, the receiving end receives the optical signal, and then processes the received optical signal using the local laser and the coherent receiver to obtain a corresponding electrical signal. Then, the electrical signal is processed by the DSP module. The processing of the electrical signal mentioned here includes but is not limited to: determining the frequency offset of the electrical signal, and further performing signal recovery on the electrical signal based on the determined frequency offset to recover the data sent by the transmitting end.

[0049] The data frames defined by the Optical Internet Forum (OIF) 400 Gbit / s zebest range (400ZR) standard and the 800 Gbit / s zebest range (800ZR) standard include training sequences and pilot symbols. Figure 2a To understand, Figure 2a A schematic diagram of the structure of a data frame is shown. Figure 2aAs shown, the data frame may include a training sequence, a pilot symbol, and a data symbol. That is to say, in this scenario, the data frame sent by the sending device to the receiving device includes a training sequence and a pilot symbol. Correspondingly, the data frame received by the receiving device also includes a training sequence and a pilot symbol. The receiving device can determine the frequency offset of the received signal based on the training sequence and the pilot symbol in the received signal. Among them, the frequency offset of the received signal generally jitters around a certain frequency offset value. Therefore, the frequency offset of the received signal can be determined by two parts. One part is the "certain frequency offset value" mentioned above, and the other part is the jitter frequency offset jittering around the "certain frequency offset value". For the convenience of description, the aforementioned "certain frequency offset value" is referred to as the "frequency offset locking value". Then: the training sequence can determine the aforementioned frequency offset locking value, and the pilot symbol can be used to determine the jitter frequency offset. For example, the frequency offset locking value determined based on the training sequence is 2 Hz, and the jitter frequency offset determined based on the pilot symbol is 0.35 Hz, then the frequency offset of the received signal can be (2+0.35) Hz. How the receiving device determines the aforementioned frequency offset lock value based on the training sequence and how the receiving device determines the jitter frequency offset based on the pilot symbol will not be described in detail here.

[0050] However, with the development of communication technology, the structure of data frames has also changed accordingly. In some scenarios, the data frames no longer include the aforementioned training sequence. For example, in 2023, OIF released the 800Gbit / s long range (800LR) standard draft. In the 800LR standard draft, the data frame structure was redesigned and the training sequence was removed. Figure 2b To understand, Figure 2b FIG. 2 shows another structural diagram of a data frame. Figure 2b As shown, the data frame no longer includes a training sequence, but includes pilot symbols and data symbols. In one example, a data frame has a total of 6144 symbols, and a pilot symbol is inserted into every 64 data symbols.

[0051] Although the data frame no longer includes the training sequence, the coherent transmission system's requirements for frequency offset are not reduced because the data frame no longer includes the training sequence. For example, the coherent transmission system's requirements for frequency offset are still ±3.6 GHz. In other words, the coherent transmission system requires that the receiving device be able to determine the frequency offset of the received signal when the frequency offset of the received signal is within the frequency offset range of ±3.6 GHz, so as to perform signal recovery on the received signal based on the determined frequency offset value.

[0052] Since the data frame no longer includes a training sequence, the receiving device can no longer determine the frequency offset of the received signal based on the training sequence and the pilot symbol. In the conventional technology, the range of the frequency offset that can be determined using only the pilot symbol in the received signal is approximately ±0.9 GHz, which cannot meet the above-mentioned requirement of ±3.6 GHz.

[0053] Therefore, how the receiving device can realize the frequency offset estimation within the frequency offset range (such as the aforementioned ±3.6 GHz or other ranges exceeding ±3.6 GHz) based on the pilot symbols in the received signal is a problem that needs to be solved urgently. The frequency offset range mentioned in the embodiment of the present application can be understood as the frequency offset range between the received carrier and the carrier of the laser of the receiving device. Among them, the received carrier refers to the carrier received by the receiving device, and the laser of the receiving device can correspond to Figure 1 The local laser at the receiving end is shown.

[0054] In order to solve the above problem, an embodiment of the present application provides a method for estimating a frequency offset. Next, the method for estimating a frequency offset is introduced in conjunction with the accompanying drawings.

[0055] See also Figure 3 , which is a flow chart of a frequency offset estimation method provided in an embodiment of the present application.

[0056] Figure 3 The method shown can be applied to a receiving device. The receiving device mentioned here can be an optical module or a PHY chip, and the embodiments of the present application do not make specific limitations.

[0057] In one example, the receiving device may include a DSP module, Figure 3 The method shown can be processed by the DSP module, for example, wherein the DSP module can be a software module or a hardware circuit, and the embodiment of the present application does not make any specific limitation.

[0058] Figure 3 The method shown may include the following S101-S103.

[0059] S101: Acquire a second signal, where the second signal includes a second pilot symbol, and the second signal is a signal received by a receiving device after a first signal sent by a sending device is transmitted.

[0060] In an embodiment of the present application, the sending device can send multiple data frames to the receiving device, and the first signal can be a signal corresponding to a certain data frame (for example, the first data frame) among the multiple data frames. Correspondingly, the second signal is a signal corresponding to the first data frame sent by the sending device to the receiving device.

[0061] As an example, the receiving device can sample multiple data frames received by itself at preset intervals to obtain a second signal. For example, the signals corresponding to the multiple data frames received by the receiving device are sampled at intervals of 10 data frames to obtain a second signal. For example: Assuming that the receiving device receives signals corresponding to 50 data frames, the receiving device can obtain the second signal corresponding to the 1st data frame, the second signal corresponding to the 11th data frame, the second signal corresponding to the 21st data frame, the second signal corresponding to the 31st data frame, and the second signal corresponding to the 41st data frame.

[0062] After sampling multiple second signals, subsequent S102-S103 can be performed based on each second signal to obtain the frequency offset estimation value of each second signal. For any second signal, the frequency offset estimation value corresponding to the second signal can be used as the frequency offset estimation value corresponding to the target number of data frames including the first data frame corresponding to the second signal. The target number can be the number of data frames included in the aforementioned preset interval. With reference to the above examples, the frequency offset estimation value of the second signal corresponding to the 1st data frame can be used as the frequency offset estimation value corresponding to the 10 data frames from the 1st data frame to the 10th data frame; the frequency offset estimation value of the second signal corresponding to the 11th data frame can be used as the frequency offset estimation value corresponding to the 10 data frames from the 11th data frame to the 20th data frame; the frequency offset estimation value of the second signal corresponding to the 21st data frame can be used as the frequency offset estimation value corresponding to the 10 data frames from the 21st data frame to the 30th data frame; the frequency offset estimation value of the second signal corresponding to the 31st data frame can be used as the frequency offset estimation value corresponding to the 10 data frames from the 31st data frame to the 40th data frame; the frequency offset estimation value of the second signal corresponding to the 41st data frame can be used as the frequency offset estimation value corresponding to the 10 data frames from the 41st data frame to the 50th data frame.

[0063] In one example, the first signal includes a first pilot symbol, which is received by a receiving device after being transmitted, and the second pilot symbol is a pilot symbol received by the receiving device after the first pilot symbol is transmitted.

[0064] As before for Figure 2b It can be seen from the description that the pilot symbols are inserted into the data symbols at certain intervals, so the second signal may include multiple second pilot symbols.

[0065] S102: Determine a first frequency offset estimation value corresponding to the second signal in a first frequency offset segment based on the second pilot symbol, where the first frequency offset segment is a frequency offset segment among a plurality of continuous frequency offset segments obtained by dividing a frequency offset range.

[0066] In an embodiment of the present application, the frequency offset range can be divided to obtain multiple continuous frequency offset segments. Regarding the frequency offset segment, it can correspond to a sub-range in the frequency offset range. Each frequency offset segment corresponds to a continuous sub-range, and the multiple continuous frequency offset segments are also continuous. In other words, the multiple continuous frequency offset segments can constitute the complete frequency offset range. In a specific example, the frequency offset range can be divided in an average division manner. In this case, the spans of the various frequency offset segments are the same. In this way, the division method is simpler. Of course, the frequency offset range can also be divided in a non-average division manner, which is not specifically limited in the embodiment of the present application.

[0067] In an embodiment of the present application, the aforementioned frequency offset range is a larger frequency offset range, which is larger than the jitter frequency offset range that can be determined based on the second pilot symbol. In addition, in order to enable the first frequency offset estimate to be accurately determined based on the second pilot symbol within the first frequency offset segment, the frequency span corresponding to each frequency offset segment in the multiple continuous frequency offset segments is less than or equal to the frequency span of the jitter frequency offset range. Because once the frequency span corresponding to the frequency offset segment is greater than the frequency span of the jitter frequency offset range, then within the frequency offset segment, the corresponding jitter frequency offset cannot be accurately estimated based on the second pilot symbol. Among them, for a certain frequency offset segment, the frequency span corresponding to the frequency offset segment is the difference between the maximum frequency and the minimum frequency corresponding to the frequency offset segment. Similarly, the frequency span of the jitter frequency offset range is the difference between the maximum frequency and the minimum frequency of the jitter frequency offset range.

[0068] In a specific example, the jitter frequency offset range that can be determined based on the second pilot symbol can be determined according to the symbol interval between adjacent second pilot symbols in the second signal and the transmission rate of the second signal. Assume that the jitter frequency offset range that can be determined based on the second pilot symbol is ±f track , where f track The unit is Hz, then f track It can be calculated by the following formula (1).

[0069]

[0070] In formula (1):

[0071] f symb is the transmission rate of the second signal;

[0072] L is the symbol interval between adjacent second pilot symbols in the second signal.

[0073] In the draft 800LR standard, f symb is 123.6 gigabaud per second (GBd / s), L is 64, and we substitute into formula (1), |f track |About 0.966GHz.

[0074] Assume that the frequency offset range is ±4.0 GHz (in compliance with the frequency offset requirements in the draft 800LR standard), and the frequency offset range is divided in an even manner, and the span of each frequency offset segment is 1.6 GHz (smaller than the span of the jitter frequency offset range). Then, the frequency offset segments can refer to Figure 4 To understand. Figure 4 A schematic diagram of a frequency offset segment provided in an embodiment of the present application. Figure 4 As shown, the frequency offset range is divided into 5 continuous frequency offset segments, corresponding to the frequency offset segment [-4.0GHz, -2.4GHz), the frequency offset segment [-2.4GHz, -0.8GHz), the frequency offset segment [-0.8GHz, 0.8GHz), the frequency offset segment [0.8GHz, 2.4GHz) and the frequency offset segment [2.4GHz, 4.0GHz].

[0075] In one example, the first frequency offset segment may be any frequency offset segment among the aforementioned multiple continuous frequency offset segments.

[0076] In one example, when S102 is implemented, the first frequency offset estimation value corresponding to the second signal in each first frequency offset segment may be determined. In another example, when S102 is implemented, the first frequency offset estimation value corresponding to the second signal in part of the first frequency offset segment may also be determined.

[0077] For any first frequency offset segment, there may be multiple implementations of determining the first frequency offset estimation value corresponding to the second signal in part of the first frequency offset segment. Two possible implementations are described below.

[0078] In one example, S102 may include the following steps A1-A3 during specific implementation.

[0079] A1: Perform frequency compensation on the second pilot symbol according to a preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol.

[0080] As mentioned above, the frequency offset of the second signal generally jitters around the frequency offset lock value. Therefore, the frequency offset of the second signal can be determined by two parts. One part is the frequency offset lock value, and the other part is the jitter frequency offset that jitters around the frequency offset lock value. In an embodiment of the present application, for the first frequency offset segment, a frequency offset lock value can be assumed for the first frequency offset segment, and the assumed frequency offset lock value is the preset frequency offset lock value. That is: if the frequency offset of the second signal is within the first frequency offset segment, the frequency offset of the second signal jitters around the preset frequency offset lock value. Then, based on the preset frequency offset lock value, a target jitter frequency offset that jitters around the preset frequency offset lock value is determined.

[0081] The embodiments of the present application do not specifically limit the preset frequency offset lock value. In one example, considering that the jitter frequency offset range that can be determined based on the second pilot symbol is a range symmetrical relative to 0 (i.e., ±**), therefore, in one example, the preset frequency offset lock value may be the center frequency of the first frequency offset segment. In other words, the first frequency offset segment is symmetrical relative to the preset frequency offset lock value, so that within the first frequency offset segment, the target jitter frequency offset can be accurately estimated based on the second pilot symbol. Of course, the preset frequency offset lock value may also be other frequencies within the first frequency offset segment, which is not specifically limited in the embodiments of the present application.

[0082] As mentioned above, the second signal may include multiple second pilot symbols. Therefore, in one example, when step A is implemented, frequency compensation may be performed on each of the multiple second pilot symbols according to the preset frequency offset lock value to obtain a first compensated pilot symbol corresponding to each second pilot symbol. In another example, when step A is implemented, frequency compensation may be performed on some of the multiple pilot symbols according to the preset frequency offset lock value to obtain a first compensated pilot symbol corresponding to each of the second pilot symbols.

[0083] In one example, for any second pilot symbol, its corresponding first compensation pilot symbol can be calculated using the following formula (2).

[0084] out1=out*e -jωt Formula (2)

[0085] In formula (2):

[0086] out1 is the first compensation pilot symbol;

[0087] out is the second pilot symbol;

[0088] ω is the angular frequency, ω=2*π*f, f is the preset frequency offset locking value;

[0089] t is the difference between the reception time of the current second pilot symbol and the reception time of the first second pilot symbol included in the second signal.

[0090] A2: Determine a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol.

[0091] After determining the first compensating pilot symbol, the phase difference between the first compensating pilot symbol and the first pilot symbol can be calculated, and then, according to the quantitative relationship between the phase and the frequency, the frequency corresponding to the phase difference is obtained, and the frequency corresponding to the phase difference can also be referred to as a jitter frequency offset. Further, according to the jitter frequency offset, the target jitter frequency offset is determined. As mentioned above, the second signal may include multiple second pilot symbols. And according to each second pilot symbol, a jitter frequency offset can be determined. Specifically, for each second pilot symbol, frequency compensation can be performed based on the aforementioned preset frequency offset lock value to obtain a first compensating pilot symbol corresponding to the second pilot symbol, and then, according to the phase difference between the first compensating pilot symbol and the first pilot symbol, the jitter frequency offset corresponding to the second pilot symbol can be determined. Therefore, in one example, when step A2 is specifically implemented, the target jitter frequency offset can be determined according to the jitter frequency offset corresponding to each second pilot symbol. For example, the average value of the jitter frequency offsets corresponding to multiple second pilot symbols can be determined as the target jitter frequency offset. In another example, when step A2 is implemented, the target jitter frequency offset may be determined according to the jitter frequency offsets corresponding to some second pilot symbols. For example, the average value of the jitter frequency offsets corresponding to some second pilot symbols may be determined as the target jitter frequency offset.

[0092] A3: Determine the first frequency offset estimation value according to the target jitter frequency offset and the preset offset lock value.

[0093] After determining the target jitter frequency offset, the first frequency offset estimate value can be determined based on the target jitter frequency offset and the preset offset lock value. In a specific example, the sum of the target jitter frequency offset and the preset offset lock value can be determined as the first frequency offset estimate value.

[0094] In one example, the first frequency offset segment may be preset with a plurality of selected frequency offset estimation values. In the specific implementation of S102, each selected frequency offset estimation value may be used to perform frequency compensation on the second pilot symbol, and a second compensation pilot symbol corresponding to each selected frequency offset estimation value may be obtained, and then, the phase difference between the second compensation pilot symbol corresponding to each selected frequency offset estimation value and the first pilot symbol may be calculated, and the phase difference corresponding to each selected frequency offset estimation value may be obtained. Then, the selected frequency offset estimation value with the smallest corresponding phase difference may be determined as the first frequency offset estimation value. Among them, for a certain selected frequency offset estimation value, frequency compensation for the second pilot symbol may be performed by using the selected frequency offset estimation value to perform frequency compensation on each second pilot symbol included in the second signal, and the second compensation pilot symbol corresponding to each second pilot symbol may be obtained. Accordingly, the phase difference corresponding to the selected frequency offset estimation value may be the average value of multiple phase differences obtained by calculating the phase difference between each second compensation pilot symbol and the first pilot symbol corresponding to it.

[0095] For example:

[0096] The first frequency offset segment corresponds to Figure 4 The frequency offset segment shown is: [0.8GHz, 2.4GHz), and the first frequency offset segment includes four selected frequency offset estimation values ​​of 0.8GHz, 1.2GHz, 1.6GHz and 2.0GHz. Then, the 96 second pilot symbols included in the second signal can be frequency compensated based on the selected frequency offset estimation value of 0.8GHz to obtain 96 second compensated pilot symbols. Then, for each of the 96 second compensated pilot symbols, the phase difference between the second compensated pilot symbol and the corresponding first pilot symbol is calculated to obtain 96 phase differences, and the average value of the 96 phase differences is calculated to obtain the phase difference corresponding to the selected frequency offset estimation value of 0.8GHz. Similarly, the phase difference corresponding to the selected frequency offset estimation value of 1.2GHz, the phase difference corresponding to the selected frequency offset estimation value of 1.6GHz, and the phase difference corresponding to the selected frequency offset estimation value of 2.0Hz can be calculated. Then, the phase differences corresponding to the candidate frequency offset estimation values ​​are compared. In one example, if the phase difference corresponding to the candidate frequency offset estimation value 1.6 GHz is the smallest, the candidate frequency offset estimation value 1.6 GHz may be used as the first frequency offset estimation value.

[0097] S103: Determine a frequency offset estimation value of the second signal according to the first frequency offset estimation value.

[0098] In an embodiment of the present application, when S103 is implemented, based on the accuracy of the first frequency offset estimation value corresponding to at least one first frequency offset segment, a first frequency offset estimation value with the highest accuracy can be selected from the first frequency offset estimation values ​​corresponding to at least one first frequency offset segment as the frequency offset estimation value of the second signal.

[0099] In one example, the accuracy of the first frequency offset estimate can be determined by the symbol decision error of the third signal obtained by frequency compensating the second signal based on the first frequency offset estimate. For a certain first frequency offset estimate, if the symbol decision error of the third signal determined based on the first frequency offset estimate is smaller, it means that the first frequency offset estimate is more accurate. As a specific example, frequency compensation can be performed on both the data symbols and the pilot symbols in the second signal based on the first frequency offset estimate to obtain the third signal. It is not difficult to understand that the third signal includes both data symbols frequency compensated based on the first frequency offset estimate and pilot symbols frequency compensated based on the first frequency offset estimate. Then, symbol decision is performed on the third signal to obtain a symbol decision error. Among them, the symbol decision error can include the sum of the absolute values ​​of the symbol decision errors of each symbol (data symbol and pilot symbol) included in the third signal. In one example, for a certain first frequency offset estimate, if the symbol decision error of the first frequency offset estimate is extremely small, for example, less than a preset error threshold, the first frequency offset estimate can be determined as the frequency offset estimate of the second signal. In another example, the symbol decision error of each first frequency offset estimate value corresponding to each of the first frequency offset segments can be calculated, and then the first frequency offset estimate value with the smallest symbol decision error can be determined as the frequency offset estimate value of the second signal.

[0100] In another example, the accuracy of the first frequency offset estimation value can be determined based on the phase difference generated by the second pilot symbol obtained by the first frequency offset estimation value during the transmission process. For a certain first frequency offset estimation value, if the phase difference generated by the second pilot symbol determined based on the first frequency offset estimation value during the transmission process is smaller, it means that the first frequency offset estimation value is more accurate. Therefore, based on the first frequency offset estimation value corresponding to each of the first frequency offset segments, the phase difference generated by the first pilot symbol during the transmission process can be determined respectively, and then the first frequency offset estimation value corresponding to the first frequency offset segment with the smallest phase difference is determined as the frequency offset estimation value of the second signal.

[0101] Regarding the phase difference generated during the transmission of the first pilot symbol, it may be an average value of the phase differences generated during the transmission of a plurality of first pilot symbols included in the first signal.

[0102] For any first pilot symbol, the phase difference generated during the transmission process can be calculated as follows:

[0103] First, the second pilot symbol is frequency compensated using the first frequency offset estimate to obtain a third compensated pilot symbol, and then the phase difference between the third compensated pilot symbol and the first pilot symbol is calculated to obtain the phase difference generated by the first pilot symbol during transmission. In one example, frequency compensation of the second pilot symbol using the first frequency offset estimate can be divided into two compensations, the first is to compensate the second pilot symbol using a preset frequency offset lock value to obtain a first compensated pilot symbol, and then, the first compensated pilot symbol is compensated using a target jitter frequency offset to obtain the third compensated pilot symbol. In another example, frequency compensation of the second pilot symbol using the first frequency offset estimate can also be performed using one-time compensation, that is, after determining the first frequency offset estimate, the second pilot symbol is directly compensated using the first frequency offset estimate to obtain the third compensated pilot symbol.

[0104] In one example, since the carrier phase recovery module must execute the step of "calculating the phase difference between the third compensation pilot symbol and the first pilot symbol" when performing carrier phase recovery, the "calculating the phase difference between the third compensation pilot symbol and the first pilot symbol" can be executed by the carrier phase recovery module, thereby reusing the existing calculation module of the receiving device.

[0105] In one example, after determining the frequency offset estimate of the second signal, frequency compensation can be performed on the data symbols in the second signal so as to restore the data sent by the transmitting device based on the frequency compensated data symbols. Regarding the specific implementation of frequency compensation for the data symbols in the second signal based on the frequency offset estimate of the second signal, it can follow the traditional method of frequency compensation for the data symbols, which is not described in detail here.

[0106] From the above description, it can be seen that, using the solution of the embodiment of the present application, even if the data frame sent by the sending device to the receiving device does not include a training sequence, the receiving device can also achieve frequency offset estimation within the frequency offset range based on the second pilot symbol in the received second signal.

[0107] The above is an introduction to the frequency offset estimation method provided in the embodiment of the present application. Next, the multiple continuous frequency offset segments are used as Figure 4 As an example, the frequency offset segment shown in Figures 5 to 7 , introduces the frequency offset estimation method provided in an embodiment of the present application.

[0108] Figure 5 A flowchart of another frequency offset estimation method provided in an embodiment of the present application.

[0109] Specifically, for Figure 4 The five first frequency offset segments shown execute S201-S205 respectively.

[0110] S201: Obtain a preset frequency offset locking value.

[0111] Among them, the preset frequency offset locking value of the frequency offset segment [-4.0GHz, -2.4GHz) is: -3.2GHz, the preset frequency offset locking value of the frequency offset segment [-2.4GHz, -0.8GHz) is: -1.6GHz, the preset frequency offset locking value of the frequency offset segment [-0.8GHz, 0.8GHz) is: 0GHz, the preset frequency offset locking value of the frequency offset segment [0.8GHz, 2.4GHz) is: 1.6GHz, and the preset frequency offset locking value of the frequency offset segment [2.4GHz, 4.0GHz] is: 3.2GHz.

[0112] S202: Perform frequency compensation on a second pilot symbol in the second signal according to the preset frequency offset locking value to obtain a first compensated pilot symbol.

[0113] In one example, the second signal may include multiple second pilot symbols, and frequency compensation may be performed on each second pilot symbol according to the preset offset lock value to obtain a first supplementary pilot symbol corresponding to each second pilot symbol.

[0114] Among them, for any second pilot symbol, frequency compensation is performed on it based on the preset frequency offset lock value. In specific implementation, the second pilot symbol can be frequency compensated by the formula (2) mentioned above to obtain the first supplementary pilot symbol corresponding to the second pilot symbol.

[0115] S203: Determine a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol.

[0116] In one example, for any second pilot symbol, the phase difference between the first compensated pilot symbol obtained by frequency compensating the second pilot symbol and the first pilot symbol can be calculated. Further, based on the quantitative relationship between the phase and the frequency, the frequency corresponding to the phase difference is obtained, and the frequency corresponding to the phase difference can also be called a jitter frequency offset.

[0117] As mentioned above, the second signal may include multiple second pilot symbols. Therefore, after performing S203 for each second pilot symbol, multiple jitter frequency offsets may be obtained (one second pilot symbol may correspond to one jitter frequency offset). In an example, a target jitter frequency offset may be determined based on the multiple jitter frequency offsets. For example, an average value of the multiple jitter frequency offsets may be determined as the target jitter frequency offset.

[0118] S204: Determine a first frequency offset estimation value according to the target jitter frequency offset and the preset offset lock value.

[0119] For any first frequency offset segment, a first frequency offset estimation value corresponding to the first frequency offset segment can be determined based on the target jitter frequency offset and the preset offset lock value. In a specific example, when S204 is implemented, the sum of the target jitter frequency offset and the preset offset lock value can be determined as the first frequency offset estimation value.

[0120] S205: Determine a phase difference generated by the first pilot symbol during transmission based on the first frequency offset estimation value.

[0121] For any first frequency offset segment, after calculating and obtaining the first frequency offset estimation value, the phase difference generated by the first pilot symbol during the transmission process can be further determined.

[0122] As mentioned above, the first signal may include multiple first pilot symbols. The phase difference generated during the transmission of the first pilot symbol may be an average value of the phase differences generated during the transmission of the multiple first pilot symbols included in the first signal.

[0123] In one example, for any first pilot symbol, the phase difference generated during the transmission process can be used to perform frequency compensation on the second pilot symbol using the first frequency offset estimate to obtain a third compensated pilot symbol, and then, the phase difference between the third compensated pilot symbol and the first pilot symbol is calculated to obtain the phase difference generated by the first pilot symbol during the transmission process.

[0124] As a specific example, frequency compensation for the second pilot symbol using the first frequency offset estimate can be divided into two compensations, the first is to compensate the second pilot symbol using a preset frequency offset lock value to obtain a first compensated pilot symbol, and then, the first compensated pilot symbol is compensated using a target jitter frequency offset to obtain the third compensated pilot symbol. As another example, frequency compensation for the second pilot symbol using the first frequency offset estimate can also be performed using one compensation, that is, after determining the first frequency offset estimate, the first frequency offset estimate is directly used to compensate the second pilot symbol to obtain the third compensated pilot symbol.

[0125] against Figure 4 After executing S201 to S205 respectively for the five first frequency offset segments, five phase differences can be obtained, and further, S206 and S207 are executed.

[0126] S206: Determine the first frequency offset estimation value with the smallest phase difference as the frequency offset estimation value of the second signal.

[0127] In one example, the five phase differences obtained may be sorted to obtain the smallest phase difference among the five phase differences, and then the first frequency offset estimation value corresponding to the smallest phase difference is determined as the frequency offset estimation value of the second signal. This is now illustrated with reference to the following Table 1:

[0128] Table 1

[0129]

[0130] In one example, if and Among these five phase differences, the smallest phase difference is Then F3 may be determined as the frequency offset estimation value of the second signal. S207: Based on the frequency offset estimation value of the second signal, frequency compensation is performed on the data symbols in the second signal.

[0131] After obtaining the frequency offset estimate of the second signal, frequency compensation can be performed on the data symbols in the second signal based on the frequency offset estimate of the second signal. The specific implementation of frequency compensation for the data symbols in the second signal based on the frequency offset estimate of the second signal can follow the traditional method of frequency compensating for data symbols, which is not described in detail here.

[0132] For other implementation details of S201-S207, please refer to the relevant description part in the previous text, which will not be repeated here.

[0133] Figure 6A flowchart of another frequency offset estimation method provided in an embodiment of the present application. Figure 6 The method shown may include the following S301-S307.

[0134] It should be noted that, compared with S201-S207, the difference between S301-S307 is that S205-S206 and S305-S306, S301-S304 and S201-S204 completely correspond, and S307 and S207 completely correspond.

[0135] Specifically, for Figure 4 The five first frequency offset segments shown execute S301-S305 respectively.

[0136] S301: Obtain a preset frequency offset locking value.

[0137] S302: Perform frequency compensation on a second pilot symbol in the second signal according to the preset frequency offset locking value to obtain a first compensated pilot symbol.

[0138] S303: Determine a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol.

[0139] S304: Determine a first frequency offset estimation value according to the target jitter frequency offset and the preset offset lock value.

[0140] Regarding S301-S304, Figure 5 The S201-S204 shown correspond to each other. For specific implementation, please refer to the description of S201-S204 in the previous text, and no repeated description is given here.

[0141] S305: Based on the first frequency offset estimation value, perform frequency compensation on the second signal to obtain a third signal, and determine a symbol decision error of the third signal.

[0142] For any first frequency offset segment, after calculating and obtaining the first frequency offset estimate value, the second signal can be frequency compensated based on the first frequency offset estimate value to obtain a third signal, and a symbol decision error of the third signal can be determined.

[0143] In one example, the second signal may be frequency compensated based on the first frequency offset estimate. Specifically, the data symbols and the second pilot symbols in the second signal may be frequency compensated based on the first frequency offset estimate. Accordingly, the third signal obtained by frequency compensating the second signal includes both the data symbols frequency compensated based on the first frequency offset estimate and the pilot symbols frequency compensated based on the first frequency offset estimate.

[0144] Then, symbol decision is performed on the third signal to obtain a symbol decision error, wherein the symbol decision error may include the sum of absolute values ​​of errors of symbol decision performed on each symbol included in the third signal.

[0145] against Figure 4 After executing S301-S305 respectively for the five first frequency offset segments shown, five symbol decision errors can be obtained, and further, S306 and S307 are executed.

[0146] S306: Determine the first frequency offset estimation value with the smallest symbol decision error as the frequency offset estimation value of the second signal.

[0147] In one example, the five symbol decision errors obtained may be sorted to obtain the smallest symbol decision error among the five phase differences, and then the first frequency offset estimation value corresponding to the smallest symbol decision error may be determined as the frequency offset estimation value of the second signal. This is now illustrated with reference to the following Table 2:

[0148] Table 2

[0149] The first frequency offset segment First frequency offset estimate The corresponding symbol decision error [-4.0GHz, -2.4GHz) F1 Δ1 [-2.4GHz, -0.8GHz) F2 Δ2 [-0.8GHz, 0.8GHz) F3 Δ3 [0.8GHz, 2.4GHz) F4 Δ4 [2.4GHz, 4.0GHz] F5 Δ5

[0150] In an example, if the smallest phase difference among the five symbol decision errors of Δ1, Δ2, Δ3, Δ4, and Δ5 is Δ3, then F3 may be determined as the frequency offset estimation value of the second signal.

[0151] S307: Perform frequency compensation on data symbols in the second signal based on the frequency offset estimation value of the second signal.

[0152] After obtaining the frequency offset estimate of the second signal, frequency compensation can be performed on the data symbols in the second signal based on the frequency offset estimate of the second signal. The specific implementation of frequency compensation for the data symbols in the second signal based on the frequency offset estimate of the second signal can follow the traditional method of frequency compensating for data symbols, which is not described in detail here.

[0153] Figure 7 A flowchart of another frequency offset estimation method provided in an embodiment of the present application. Figure 7 The method shown may include the following S401-S407.

[0154] S401: traverse a plurality of first frequency offset segments in a certain order.

[0155] In one example, the five first frequency offset segments may be traversed in the order of [-4.0 GHz, -2.4 GHz)→[-2.4 GHz, -0.8 GHz)→[-0.8 GHz, 0.8 GHz)→[0.8 GHz, 2.4 GHz)→[2.4 GHz, 4.0 GHz].

[0156] S402: For the first frequency offset segment currently traversed, obtain a preset frequency offset locking value corresponding to the first frequency offset segment.

[0157] S403: Perform frequency compensation on a second pilot symbol in the second signal according to the preset frequency offset locking value to obtain a first compensated pilot symbol.

[0158] S404: Determine a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol.

[0159] S405: Determine a first frequency offset estimation value according to the target jitter frequency offset and the preset offset lock value.

[0160] S402-S405 and Figure 5 The specific implementation of S201-S204 shown corresponds to that of S402-S405, and reference may be made to the description of S201-S204 above, which will not be repeated here.

[0161] S406: Based on the first frequency offset estimation value, perform frequency compensation on the second signal to obtain a third signal, and determine a symbol decision error of the third signal.

[0162] S406 and Figure 6 Corresponding to S305 shown, the specific implementation of S406 can refer to the description of S305 in the previous text, and will not be repeated here.

[0163] S407: Determine whether the symbol decision error of the third signal is less than a preset error threshold.

[0164] In one example, if the symbol decision error of the third signal is greater than or equal to a preset error threshold, it means that the symbol decision error of the third signal is large. Accordingly, it can be determined that the first frequency offset estimate determined by S405 is inaccurate. Therefore, if the symbol decision error of the third signal is greater than or equal to the preset error threshold, S401 can be executed to continue to traverse the multiple first frequency offset segments, and execute subsequent steps to determine the frequency offset estimate of the second signal from other first frequency offset segments.

[0165] In another example, if the symbol decision error of the third signal is less than the preset error threshold, it means that the symbol decision error of the third signal is extremely small. Accordingly, it can be determined that the first frequency offset estimate determined by S405 is accurate. Therefore, if the symbol decision error of the third signal is less than the preset error threshold, S408-S409 is executed.

[0166] S408: Determine the first frequency offset estimation value as the frequency offset estimation value of the second signal.

[0167] S409: Perform frequency compensation on data symbols in the second signal based on the frequency offset estimation value of the second signal.

[0168] After obtaining the frequency offset estimate of the second signal, frequency compensation can be performed on the data symbols in the second signal based on the frequency offset estimate of the second signal. The specific implementation of frequency compensation for the data symbols in the second signal based on the frequency offset estimate of the second signal can follow the traditional method of frequency compensating data symbols, which is not described in detail here.

[0169] Based on the frequency offset estimation method provided in the above embodiment, the embodiment of the present application further provides a receiving device. The receiving device is described below in conjunction with the accompanying drawings.

[0170] See also Figure 8 , which is a structural schematic diagram of a receiving device provided in an embodiment of the present application. Figure 8 The receiving device 800 shown is used to execute the frequency offset estimation method performed by the receiving device provided in the above method embodiment.

[0171] like Figure 8 As shown, the receiving device 800 includes: an acquisition unit 801 and a processing unit 802.

[0172] The acquisition unit 801 is used to acquire a second signal, where the second signal includes a second pilot symbol, and the second signal is a signal received by a receiving device after a first signal sent by a sending device is transmitted.

[0173] The processing unit 802 is used to determine, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, where the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; and determine a frequency offset estimate of the second signal according to the first frequency offset estimate.

[0174] In one possible implementation, the processing unit 802 is used to: perform frequency compensation on the second pilot symbol according to a preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol; determine a target jitter frequency offset according to a phase difference between the first compensated pilot symbol and the first pilot symbol, wherein the first signal includes the first pilot symbol, and the second pilot symbol is a symbol received by a receiving device after the first pilot symbol is transmitted; determine the first frequency offset estimate value according to the target jitter frequency offset and the preset offset lock value.

[0175] In a possible implementation manner, the preset frequency offset locking value corresponding to the first frequency offset segment is the center frequency of the first frequency offset segment.

[0176] In one possible implementation, the second signal includes multiple second pilot symbols, and the second pilot symbols are frequency compensated according to a preset frequency offset locking value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol, including: frequency compensating each second pilot symbol among the multiple second pilot symbols according to the preset frequency offset locking value to obtain a first compensated pilot symbol corresponding to each second pilot symbol.

[0177] In a possible implementation, determining the target jitter frequency offset based on the phase difference between the first compensation pilot symbol and the first pilot symbol includes: obtaining the phase difference corresponding to each first compensation pilot symbol based on the first compensation pilot symbol corresponding to each second pilot symbol and each first pilot symbol; determining the jitter frequency offset corresponding to each first compensation pilot symbol based on the phase difference corresponding to each first compensation pilot symbol; and determining the target jitter frequency offset based on the jitter frequency offset corresponding to each first compensation pilot symbol.

[0178] In one possible implementation, the processing unit 802 is used to: determine the phase difference generated by the first pilot symbol during the transmission process based on the first frequency offset estimation value corresponding to each of the first frequency offset segments; and determine the first frequency offset estimation value corresponding to the first frequency offset segment with the smallest phase difference as the frequency offset estimation value of the second signal.

[0179] In a possible implementation manner, the multiple continuous frequency offset segments are obtained by dividing the frequency offset range in an even division manner.

[0180] In one possible implementation, the frequency offset range is larger than a jitter frequency offset range that can be determined based on the second pilot symbol, and the frequency span corresponding to each frequency offset segment in the multiple continuous frequency offset segments is less than or equal to the frequency span of the jitter frequency offset range.

[0181] In a possible implementation manner, the frequency offset range is a frequency offset range between a received carrier and a carrier of a laser of the receiving device.

[0182] In a possible implementation manner, the processing unit 802 is further configured to: perform frequency compensation on data symbols in the second signal based on a frequency offset estimate of the second signal.

[0183] For the specific implementation of each step executed by each unit of the receiving device 800, reference may be made to the relevant description of the above method embodiment, and a repeated description will not be made here.

[0184] The present application also provides an integrated circuit. Fig. 9 , Fig. 9 A schematic diagram of the structure of an integrated circuit provided in an embodiment of the present application. Fig. 9 As shown, the integrated circuit 900 includes: an interface circuit 901 and a processing circuit 902 .

[0185] The interface circuit 901 is used to obtain a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted;

[0186] The processing circuit 902 is used to determine, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, where the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; and determine a frequency offset estimate of the second signal according to the first frequency offset estimate.

[0187] Regarding how the processing circuit 902 determines the first frequency offset estimation value corresponding to the second signal in the first frequency offset segment based on the second pilot symbol, reference may be made to the relevant description of the above method embodiment, which will not be repeated here.

[0188] In addition, an embodiment of the present application also provides a communication system, which includes a sending device and a receiving device, the sending device is used to send a first signal to the receiving device, and the receiving device is used to obtain a second signal, the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment is determined, and the first frequency offset segment is a frequency offset segment in multiple continuous frequency offset segments obtained by dividing the frequency offset range; according to the first frequency offset estimate, a frequency offset estimate of the second signal is determined.

[0189] For each step executed by the receiving device, reference may be made to the relevant description of the above method embodiment, which will not be repeated here.

Claims

1. A method for estimating a frequency offset, characterized in that: Applied to a receiving device, the method comprises: Acquire a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; Determine, based on the second pilot symbol, a first frequency offset estimation value corresponding to the second signal in a first frequency offset segment, wherein the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; A frequency offset estimate of the second signal is determined based on the first frequency offset estimate.

2. The method according to claim 1, characterized in that The determining, based on the second pilot symbol, a first frequency offset estimation value corresponding to the second signal in the first frequency offset segment comprises: Performing frequency compensation on the second pilot symbol according to a preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol; determining a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol, wherein the first signal includes the first pilot symbol, and the second pilot symbol is a symbol received by a receiving device after the first pilot symbol is transmitted; The first frequency offset estimation value is determined according to the target jitter frequency offset and the preset offset lock value.

3. The method according to claim 2, characterized in that The preset frequency offset locking value corresponding to the first frequency offset segment is the center frequency of the first frequency offset segment.

4. The method according to claim 2 or 3, characterized in that: The second signal includes a plurality of second pilot symbols, and frequency compensation is performed on the second pilot symbols according to a preset frequency offset lock value corresponding to the first frequency offset segment to obtain a first compensated pilot symbol, including: Frequency compensation is performed on each of the multiple second pilot symbols according to the preset frequency offset locking value to obtain a first compensated pilot symbol corresponding to each second pilot symbol.

5. The method according to claim 4, characterized in that The determining a target jitter frequency offset according to a phase difference between the first compensation pilot symbol and the first pilot symbol includes: Obtaining a phase difference corresponding to each of the first compensation pilot symbols according to the first compensation pilot symbol corresponding to each of the second pilot symbols and each of the first pilot symbols; Determine a jitter frequency offset corresponding to each of the first compensation pilot symbols according to a phase difference corresponding to each of the first compensation pilot symbols; The target jitter frequency offset is determined based on the jitter frequency offset corresponding to each first compensation pilot symbol.

6. The method according to any one of claims 1 to 5, characterized in that: The determining, according to the first frequency offset estimation value, a frequency offset estimation value of the first signal comprises: Based on the first frequency offset estimation value corresponding to each of the first frequency offset segments, respectively determine the phase difference generated by the first pilot symbol during the transmission process; The first frequency offset estimation value corresponding to the first frequency offset segment with the smallest phase difference is determined as the frequency offset estimation value of the second signal.

7. The method according to any one of claims 1 to 6, characterized in that: The multiple continuous frequency offset segments are obtained by dividing the frequency offset range in an even division manner.

8. The method according to claim 7, characterized in that The frequency offset range is larger than a jitter frequency offset range that can be determined based on the second pilot symbol, and a frequency span corresponding to each frequency offset segment in the multiple continuous frequency offset segments is smaller than or equal to a frequency span of the jitter frequency offset range.

9. The method according to any one of claims 1 to 8, characterized in that: The frequency offset range is the frequency offset range between the received carrier and the carrier of the laser of the receiving device.

10. The method according to any one of claims 1 to 9, characterized in that: The method further comprises: Frequency compensation is performed on data symbols in the second signal based on the frequency offset estimate of the second signal.

11. A receiving device, characterized in that: The receiving device comprises: an acquiring unit, configured to acquire a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; A processing unit is used to determine, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, where the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; and determine a frequency offset estimate of the second signal according to the first frequency offset estimate.

12. The receiving device according to claim 11, characterized in that The receiving device comprises: Optical module or physical layer PHY chip.

13. An integrated circuit, characterized in that: The integrated circuit comprises: The interface circuit is used to obtain a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; A processing circuit is used to determine, based on the second pilot symbol, a first frequency offset estimate corresponding to the second signal in a first frequency offset segment, wherein the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; and determine a frequency offset estimate of the second signal according to the first frequency offset estimate.

14. A communication system, characterized in that: The communication system comprises: a sending device and a receiving device; The sending device is used to send a first signal to the receiving device; The receiving device is used to obtain a second signal, wherein the second signal includes a second pilot symbol, and the second signal is a signal received by the receiving device after the first signal sent by the sending device is transmitted; Determine, based on the second pilot symbol, a first frequency offset estimation value corresponding to the second signal in a first frequency offset segment, wherein the first frequency offset segment is a frequency offset segment in a plurality of continuous frequency offset segments obtained by dividing a frequency offset range; A frequency offset estimate of the second signal is determined based on the first frequency offset estimate.

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