Method and apparatus for encoding and decoding signals transmitted in a fieldbus communication network

Abstract

This invention relates to fieldbus technology and signal encoding / decoding technology, and particularly to a method, apparatus, and computer storage medium for encoding and decoding signals transmitted in a fieldbus communication network. According to one aspect of the invention, a method for encoding signals transmitted in a fieldbus communication network comprises the following steps: filling data bits into a data segment of a signal frame; filling unused bits having a set value pattern into portions of the data segment not filled by the data bits; and encapsulating the data segment to generate the signal frame, wherein the value pattern is set such that: a) the values ​​of the filled unused bits are periodic; and b) when the signal frame is transmitted, at least one component of an electromagnetic radiation frequency associated with the periodicity is less than a set threshold.

Description

Technical Field

[0001] This invention relates to fieldbus technology and signal encoding / decoding technology, and particularly to a method for encoding and decoding signals transmitted in a fieldbus communication network, an apparatus for implementing the method, and a computer storage medium for implementing the method. Background Technology

[0002] CAN bus networks offer strong real-time data communication between nodes and easily facilitate redundant structures, improving system reliability and flexibility. CAN's high performance and reliability are widely recognized, and it is extensively used in industrial automation, shipbuilding, medical equipment, and other industrial applications.

[0003] With the rapid development of industries such as electronics, semiconductors, and communications, the demand for intelligent automotive electronics is also increasing. To enhance product competitiveness, automakers are incorporating more and more electronic control systems into vehicle control. However, since the actual usage rate of automotive CAN systems is typically limited to a maximum of 500 kbit / s, the significant increase in electronic control units (ECUs) leads to a sharp increase in bus load, causing network congestion and affecting the reliability and real-time performance of information transmission.

[0004] CAN-FD offers higher bandwidth than the CAN bus and represents an upgrade from it. It inherits the main characteristics of the CAN bus, increases network communication bandwidth, and improves the rate of missed frame detection, while maintaining most of the network system's hardware and software, especially the physical layer, unchanged. The CAN-FD protocol fully utilizes reserved bits in the CAN bus to distinguish between different frame formats. When applying the CAN-FD protocol to existing automotive networks, a CAN-FD controller needs to be added; however, CAN-FD can also participate in the existing CAN communication network, improving network system compatibility.

[0005] Electromagnetic compatibility (EMC) mainly includes the adverse electromagnetic interference (EMI) generated by the system itself and its sensitivity to external electromagnetic signals (EMS). Because EMC performance has a significant impact on CAN systems, it has become an important performance indicator for the system. Summary of the Invention

[0006] One object of the present invention is to provide a method and apparatus for encoding signals transmitted in a fieldbus communication network, which can reduce electromagnetic interference emissions during signal transmission.

[0007] A method for encoding signals transmitted in a fieldbus communication network according to one aspect of the present invention comprises the following steps:

[0008] Fill the data bits into the data segment of a signal frame;

[0009] Fill the unused bits with a set value pattern into the portion of the data segment that is not filled with the data bits; and

[0010] Encapsulate the data segment to generate the signal frame.

[0011] The value selection mode is set such that:

[0012] a) The values ​​of the unused bits that are filled have a periodicity; and

[0013] b) When the signal frame is transmitted, at least one component of the electromagnetic radiation frequency associated with the periodicity is less than a set threshold.

[0014] Preferably, in the above method, the signal frame is a CAN frame or a CAN-FD frame.

[0015] Preferably, in the above method, the values ​​of the unused bits filled within a byte are periodic.

[0016] Preferably, in the above method, the unused bits that are filled are repeatedly taken within a byte at a period of more than 1.

[0017] Preferably, in the above method, the value mode is one of the following: "11001100", "00110011", "10101010", and "01010101".

[0018] Preferably, in the above method, the at least one electromagnetic radiation frequency associated with the periodicity is determined as:

[0019]

[0020] Among them, f n Where n is the electromagnetic radiation frequency, n is a natural number greater than or equal to 1, Bund_rate is the transmission rate of the CAN frame or CAN-FD frame, and N is the period of repetition of the filled bits within one byte.

[0021] An apparatus for encoding signals transmitted in a fieldbus communication network according to another aspect of the invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the program is executed to:

[0022] Fill the data bits into the data segment of a signal frame;

[0023] Fill the unused bits with a set value pattern into the portion of the data segment that is not filled with the data bits; and

[0024] Encapsulate the data segment to generate the signal frame.

[0025] The value selection mode is set such that:

[0026] a) The values ​​of the unused bits that are filled have a periodicity; and

[0027] b) When the signal frame is transmitted, at least one component of the electromagnetic radiation frequency associated with the periodicity is less than a set threshold.

[0028] Another object of the present invention is to provide a method and apparatus for encoding signals transmitted in a fieldbus communication network.

[0029] A method for decoding signals transmitted in a fieldbus communication network according to another aspect of the present invention comprises the following steps:

[0030] Receive signal frames encoded using the method described above;

[0031] Extracting data segments from the signal frame; and

[0032] The data bits are obtained by identifying unused bits based on the value pattern.

[0033] An apparatus for decoding signals transmitted in a fieldbus communication network, according to another aspect of the invention, comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is executed to:

[0034] Receive signal frames generated by the apparatus described above;

[0035] Extracting data segments from the signal frame; and

[0036] The data bits are obtained by identifying unused bits based on the value pattern.

[0037] The present invention also provides a computer-readable storage medium storing a computer program thereon, characterized in that the program, when executed by a processor, implements the method described above.

[0038] In several embodiments of the present invention, periodically valued bits are stuffed into the unfilled portions of a data segment according to a specific stuffing pattern. By selecting a suitable stuffing pattern, the components of electromagnetic radiation frequencies or electromagnetic interference levels associated with periodicity can be reduced. Since only the signal encoding method is modified, it can be implemented in software without changing the hardware structure. Furthermore, existing communication protocols do not mandate the stuffing method for unfilled portions, thus the above encoding method has good compatibility. Attached Figure Description

[0039] The above and / or other aspects and advantages of the present invention will become clearer and more readily understood from the following description taken in conjunction with the accompanying drawings, in which like or similar elements are denoted by the same reference numerals. The drawings include:

[0040] Figure 1 This is an exemplary spectrum diagram regarding electromagnetic emission interference in a CAN system.

[0041] Figure 2 for Figure 1 A magnified view of a portion of the spectrum shown.

[0042] Figure 3A and 3B These are schematic diagrams of CAN frame format and CAN-FD frame format, respectively.

[0043] Figure 4A This illustrates a scenario where five or more consecutive bits with the same value appear in a bitstream.

[0044] Figure 4B This diagram illustrates bit stuffing performed on the bit stream by the transmitting side and destuffing performed on the bit stream from the transmitting side by the receiving side.

[0045] Figure 5 A schematic waveform diagram of a CAN-FD frame containing unused bits.

[0046] Figure 6 Here is another exemplary spectrum diagram regarding electromagnetic emission interference in a CAN system.

[0047] Figure 7 This is a flowchart of a method for encoding signals transmitted in a fieldbus communication network according to an embodiment of the present invention.

[0048] Figure 8 This is a flowchart of a method for decoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention.

[0049] Figure 9This is a schematic block diagram of an apparatus for encoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention.

[0050] Figure 10 This is a schematic block diagram of an apparatus for decoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention. Detailed Implementation

[0051] The invention will now be described more fully with reference to the accompanying drawings, which illustrate exemplary embodiments of the invention. However, the invention may be implemented in various forms and should not be construed as being limited to the embodiments given herein. The foregoing embodiments are intended to make the disclosure herein complete and comprehensive, so as to convey the full scope of protection of the invention to those skilled in the art.

[0052] In this specification, terms such as "comprising" and "including" indicate that, in addition to having units and steps that are directly and explicitly stated in the specification and claims, the technical solution of the present invention does not exclude the presence of other units and steps that are not directly or explicitly stated.

[0053] In this specification, terms such as "first" and "second" do not indicate the order of the units in terms of time, space, size, etc., but are merely used to distinguish the units.

[0054] In this specification, "coupling" should be understood to include situations in which electrical energy or electrical signals are directly transmitted between two units, or in situations in which electrical energy or electrical signals are indirectly transmitted through one or more third units.

[0055] Figure 1 This is an exemplary spectrum diagram regarding electromagnetic emission interference from a CAN system. In this example, the CAN system is based on the CAN-FD protocol with a data transmission rate of 2 Mbit / s. Figure 1 The horizontal axis represents frequency in MHz; the vertical axis represents the amplitude of the frequency component in dBμV / m.

[0056] Figure 1 The three curves a, b, and c in the figure represent the electromagnetic emission interference spectrum curves of the CAN system obtained by different measurement methods (Standby-Qp method, Standby-Pk method, and Standby-Av method). Figure 1 As shown, the electromagnetic emission interference level exceeds the threshold level near 1.66MHz. Figure 1 The horizontal line segments H_Qp and H_Av in the figure represent the threshold levels in Standby-Qp and Standby-Av modes, respectively.

[0057] Figure 2 for Figure 1 A magnified view of a portion of the spectrum shown. See also... Figure 2 The electromagnetic emission interference spectrum curve a is approximately 5.1 dB higher than the threshold H_Qp near 1.662 MHz.

[0058] For many applications, it is necessary to ensure that within a certain frequency range (e.g.) Figure 1 The electromagnetic emission interference level in the 0.53MHz to 1.8MHz band does not exceed the threshold level. However, the complexity of the system makes it difficult to determine the electromagnetic emission interference source (e.g., the source causing interference in a specific frequency band) for a particular frequency band. Figure 1 (Interference sources whose electromagnetic emission interference levels exceed the threshold around 1.66MHz). Therefore, emission protection measures are usually general and not specific. Common protection measures include selecting components with good electromagnetic compatibility performance, using surface mount packaging, and reasonable component layout.

[0059] However, after in-depth research, the inventors of this invention discovered that electromagnetic interference sources at specific frequencies may be related to the stuffing method or value pattern of non-data bits within a data segment. Therefore, interference sources at specific frequencies can be eliminated or suppressed by selecting an appropriate value pattern. This will be described in detail below.

[0060] CAN bus data frames are distinguished by standard format and extended format. The standard frame format is as follows: Figure 3A As shown in the attached diagram, a standard CAN data frame includes an arbitration segment (ARB_PHASE) and a data segment (DATA_PHASE). Figure 3B This is a schematic diagram of the CAN-FD frame format. Figure 3B The CAN-FD frame shown is Figure 3A Compared to the standard CAN frame, the CAN-FD frame has the following characteristics: In the CAN-FD frame, the arbitration segment (ARB_PHASE) has the same transmission rate as the CAN frame, while the data segment (DATA_PHASE) has a minimum transmission rate of 2 Mbit / s and a maximum of 5 Mbit / s; the CAN-FD frame has a larger data payload, and a single frame can transmit up to 64 bytes of data.

[0061] To ensure sufficient clock edges for resynchronization of bus nodes during communication, according to the CAN frame protocol and CAN-FD frame encoding rules, during framing, if the transmitting side detects five consecutive bits of the same value or polarity in the bitstream between the frame start and the cyclic check segment, it will insert a supplementary bit with the opposite value or polarity (this insertion operation is also called "bit stuffing"). Conversely, when the receiving side receives the bitstream after bit stuffing, it will automatically delete the supplementary bit immediately following the five consecutive bits of the same value. Figure 4A This illustrates a scenario where five or more consecutive bits of the same value appear in a bitstream. Figure 4B This diagram illustrates bit stuffing performed on the bit stream by the transmitting side (represented by ECU1 in the diagram) and destuffing performed on the bit stream received via the CAN bus by the receiving side (represented by ECU2 in the diagram).

[0062] When filling data segments of CAN and CAN-FD frames with data bits, it cannot be guaranteed that the data segment will always be completely filled with data bits. For the unfilled portions of the data segment, they are typically filled with bits of value "0" (0x00 in hexadecimal) or bits of value "1" (0xFF in hexadecimal). To distinguish this from data bit filling operations and bit filling operations, the filling operation for unfilled data bits will be referred to as "stuffing," and the stuffed bits will be called unused bits or stuffed bits. Figure 5 A schematic waveform diagram of a CAN-FD frame containing different bits.

[0063] Since the stuffing bitstream consists of all "0"s or all "1"s, according to the CAN frame protocol and CAN-FD frame encoding rules, a padding bit of opposite polarity should be inserted after every 5 stuffing bits. For example, a bitstream consisting of all "0"s, "0000000000000000000000000…", will be transformed into "00000" after the bit stuffing operation. 1 00000 1 00000 1 00000 1 0000… This means that the padding bit “1” appears in the packed bit stream at a fixed period (6 bits per period). When a CAN frame or CAN-FD frame containing this bit stream is transmitted over a communication medium (e.g., cable), electromagnetic interference will peak at the frequency associated with this fixed period. The associated frequency here includes the fundamental frequency and its higher harmonics, which can be determined using the following formula:

[0064]

[0065] Here, f n The associated frequency or electromagnetic radiation frequency, n is a natural number greater than or equal to 1, Bund_rate is the transmission rate of the CAN frame or CAN-FD frame, and N is the period during which the supplementary bit is "1".

[0066] Assuming a data transfer rate (Bund_rate) of 2 Mbit / s and a period of 6, the peak frequencies of electromagnetic interference can be determined as 333 kHz (fundamental frequency), 666 kHz (second harmonic), 999 kHz (third harmonic), 1.332 MHz (fourth harmonic), 1.665 MHz (fifth harmonic), and so on. This is consistent with... Figure 1 The example shown matches.

[0067] It should be noted that although the above description of the method for determining the peak frequency of electromagnetic emission interference is based on a bit stream with all "0" values ​​as the filling bits, the above method is still applicable to bit streams with all "1" values ​​as the filling bits. Specifically, the value of the supplementary bits is "0" in this case, the value period is still 6 bits, and the peak frequency of electromagnetic emission interference can still be determined using the above formula (1).

[0068] In several embodiments of the present invention, a specified spectral range (e.g., by employing an appropriate filling bit value pattern) is specified. Figure 1 The electromagnetic emission interference level (i.e., the components of each electromagnetic radiation frequency) in the range of 0.53MHz to 1.8MHz is controlled below a set threshold level. A broader objective is to control the electromagnetic emission interference level (i.e., the components of that electromagnetic radiation frequency) at one or more specified frequencies below a set threshold level by employing an appropriate filling bit value pattern.

[0069] The following section will further describe how to control electromagnetic emission interference levels using appropriate value patterns.

[0070] In the following description, the value pattern is characterized by the period in which the filled bits are either "1" or "0". It should be noted that the value period can be either the period in which the filled bits are "1" or the period in which the filled bits are "0". For example, the period in which the filled bits are "1" is used as the value period in the following description, but it is easy to understand that the description also applies to the case where the period in which the filled bits are "0" is used as the value period.

[0071] As can be seen above, when the stuffing bits are all "0", the bit stuffing encoding rules result in a value cycle of 6 (a cycle of "1"). However, when the stuffing bit value pattern is set to a non-all "0" pattern (especially avoiding a pattern of 5 or more all "0" values), the value cycle will be less than 6. Examples of such non-all "0" patterns include, but are not limited to, "0000100001...", "1000010000...", "11001100...", "00110011...", "001001001...", "100100100...", "10101010...", and "01010101...".

[0072] Table 1 shows the relationship between the fundamental frequency of the electromagnetic emission interference peak and the period of the filling bit (the period with a value of 1), which can be determined using the above equation (1).

[0073] Table 1

[0074]

[0075]

[0076] In Table 1, the value periods 6 and 1 are equivalent, so the associated base frequency is 333KHz. When the value periods are 2 and 4, the filled bits periodically take the value "1" within a byte, and the associated base frequencies are 1000KHz and 500KHz, respectively. When the value periods are 3 and 5, the associated base frequencies are 667KHz and 400KHz, respectively. The filled bits periodically take the value "1" within multiple bytes. That is to say, the value of the filled bits is not periodic within a byte.

[0077] In several embodiments of the present invention, the value pattern examples in Table 1 corresponding to period 2 or 4 are used to fill the portion of the data segment that is not filled with data bits, thereby allowing the specified frequency range (e.g.) to be filled with data bits. Figure 1 The electromagnetic emission interference level (0.53MHz to 1.8MHz) is controlled below a set threshold level, or the electromagnetic emission interference level at one or more specified frequencies is controlled below a set threshold level.

[0078] Figure 6 This is another exemplary spectrum diagram regarding electromagnetic emission interference in a CAN system. In this example, the CAN system is based on the CAN-FD protocol with a data transmission rate of 2 Mbit / s. Figure 6 The horizontal axis represents frequency in MHz; the vertical axis represents the amplitude of the frequency component in dBμV / m.

[0079] Figure 6 Curves d (black solid line) and e (light gray curve) represent electromagnetic emission interference spectrum curves under different value modes (measurement method is Standby-Qp). Curve d corresponds to the electromagnetic emission interference spectrum curve under the value mode "00000000" (i.e., the case with a value period of 6 in Table 1), while curve e corresponds to the electromagnetic emission interference spectrum curve under the value mode "11001100" (i.e., the case with a value period of 4 in Table 1).

[0080] like Figure 6 As shown, curve d peaks near frequencies of 666 kHz, 999 kHz, 1332 kHz, and 1665 kHz (labeled ①, ②, ③, and ④ in the figure, respectively), while curve e peaks near frequencies of 500 kHz, 1000 kHz, and 1500 kHz (labeled ⑤, ⑥, and ⑦ in the figure, respectively). Comparing curves d and e reveals that, at most frequencies, the former generates greater electromagnetic interference than the latter. This means that by using the value mode "11001100", the overall level of electromagnetic interference can be reduced. Furthermore, see... Figure 6 Around 1.66MHz, the electromagnetic emission interference level of curve d exceeds the threshold level. Figure 6 The horizontal line segment H_Qp in the figure represents the threshold level under the Standby-Qp mode, while the electromagnetic interference level of curve e is significantly lower than the threshold level, and the electromagnetic interference levels of curves d and e at this frequency differ by 14dB. In other words, by adopting the value mode "11001100", the electromagnetic interference level at a specific frequency can be reduced.

[0081] Figure 7 This is a flowchart illustrating a method for encoding signals transmitted in a fieldbus communication network according to an embodiment of the present invention. In this embodiment, a CAN bus communication network is used as a specific example of a fieldbus communication network, and a CAN-FD frame is used as a specific example of a signal frame. However, those skilled in the art will recognize upon reading this specification that the principles of the present invention can also be applied to other types of fieldbus communication networks.

[0082] like Figure 7 As shown, in step S701, the received data bits are filled into a data segment of a CAN-FD frame.

[0083] Then proceed to step S702, which determines whether the data segment has been filled with the received data bits. If so, proceed to step S703; otherwise, proceed to step S704.

[0084] In step S703, the data segment is encapsulated according to the format specified by the frame protocol to generate a CAN-FD signal frame.

[0085] Returning to step S704, another branch of step S702, in step S704, for the portion of the data segment not filled with data bits, bits are filled according to a set value pattern. As described above, by selecting an appropriate value pattern, the overall level of electromagnetic interference (EMI) within a specified frequency range or the EMI level at one or more specified frequencies can be reduced. In this embodiment, the appropriate value pattern can be selected according to application requirements. For example, to reduce the EMI level near 1.66MHz, a value pattern with a period of 2, 3, 4, or 5 can be considered; or, to reduce the overall EMI level, a value pattern with a period of 2 or 4 can be considered, such as "11001100", "00110011", "10101010", and "01010101". In summary, by selecting an appropriate value pattern, the values ​​of the filled bits are periodic, and when the signal frame is transmitted, at least one component of the electromagnetic radiation frequency associated with the periodicity or the EMI level is less than a set threshold.

[0086] The specific details regarding value selection patterns and bit stuffing operations have been provided above. Figure 1-6 A detailed description has been provided, so it will not be repeated here.

[0087] After step S704, Figure 7 The process shown proceeds to step S703.

[0088] Figure 8 This is a flowchart illustrating a method for decoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention. In this embodiment, a CAN bus communication network is used as a specific example of a fieldbus communication network, and a CAN-FD frame is used as a specific example of a signal frame. However, those skilled in the art will recognize upon reading this specification that the principles of the present invention can also be applied to other types of fieldbus communication networks.

[0089] like Figure 8 As shown, in step S801, the receiver receives according to... Figure 7 The CAN-FD frame generated by the embodiment shown.

[0090] Then, step S802 is performed to extract a data segment from the received CAN-FD frame. The extracted data segment may be completely filled with data bits, or it may contain unused bits filled according to a value pattern.

[0091] Next, in step S803, the unused bits are identified based on the value pattern, thereby determining the data bits within the data segment.

[0092] Figure 9 This is a schematic block diagram of an apparatus for encoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention.

[0093] Figure 9 The illustrated device 90 includes a memory 910, a processor 920, and a computer program 930 stored in the memory 910 and executable on the processor 920, wherein executing the computer program 930 can achieve the above-mentioned functions. Figure 7 The method described herein is for encoding signals transmitted in a fieldbus communication network.

[0094] Figure 10 This is a schematic block diagram of an apparatus for decoding signals transmitted in a fieldbus communication network according to another embodiment of the present invention.

[0095] Figure 10 The illustrated device 100 includes a memory 1010, a processor 1020, and a computer program 1030 stored in the memory 1010 and executable on the processor 1020, wherein executing the computer program 1030 can achieve the above-mentioned functions. Figure 8 The method described herein is for decoding signals transmitted in a fieldbus communication network.

[0096] According to another aspect of the invention, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed by a processor, can realize the above-described functions. Figure 7 The method described herein is for encoding signals transmitted in a fieldbus communication network.

[0097] According to another aspect of the invention, a computer-readable storage medium is also provided, on which a computer program is stored, which, when executed by a processor, can realize the above-described functions. Figure 8 The method described herein is for decoding signals transmitted in a fieldbus communication network.

[0098] The term "computer-readable storage medium" as used herein includes various types of computer storage media, and can be any available medium accessible to a general-purpose or special-purpose computer. For example, a computer-readable storage medium may include RAM, ROM, EPROM, E2PROM, registers, hard disks, removable disks, CD-ROMs or other optical disc storage, magnetic disk storage or other magnetic storage devices, or any other temporary or non-temporary medium capable of carrying or storing desired program code units having the form of instructions or data structures and accessible by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. As used herein, disks typically magnetically copy data, while discs optically copy data using lasers. Combinations of the above should also be included within the scope of protection of computer-readable storage media. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and storage medium may reside as discrete components in the user terminal.

[0099] Those skilled in the art will understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described herein can be implemented as electronic hardware, computer software, or a combination of both.

[0100] To demonstrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps have been generally described above according to their functionality. Whether such functionality is implemented in hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in varying ways for specific applications; however, such implementation decisions should not be construed as departing from the scope of this invention.

[0101] The embodiments and examples presented herein are provided to best illustrate embodiments according to the present technology and its particular applications, thereby enabling those skilled in the art to practice and use the invention. However, those skilled in the art will understand that the above description and examples are provided merely for ease of illustration and example. The descriptions presented are not intended to cover all aspects of the invention or to limit the invention to the precise forms disclosed.

Claims

1. A method for encoding signals transmitted in a fieldbus communication network, comprising the following steps: Fill the data bits into the data segment of a signal frame; Fill the unused bits with a set value pattern into the portion of the data segment that is not filled with the data bits; and The data segment is encapsulated to generate the signal frame. in, The value selection mode is set such that: a) The values ​​of the unused bits that are filled have a periodicity; and b) When the signal frame is transmitted, at least one component of the electromagnetic radiation frequency associated with the periodicity is less than a set threshold.

2. The method as described in claim 1, wherein, The signal frame is a CAN frame or a CAN-FD frame.

3. The method as described in claim 2, wherein, The values ​​of the unused bits that are filled within a byte are periodic.

4. The method of claim 3, wherein, The unused bits that are filled are repeated within a byte at a period greater than 1.

5. The method of claim 3, wherein, The value pattern is one of the following: "11001100", "00110011", "10101010", and "01010101".

6. The method of claim 4, wherein, The at least one electromagnetic radiation frequency associated with the periodicity is determined as follows: Among them, f n Where n is the electromagnetic radiation frequency, n is a natural number greater than or equal to 1, Bund_rate is the transmission rate of the CAN frame or CAN-FD frame, and N is the period of repetition of the filled bits within one byte.

7. An apparatus for encoding signals transmitted in a fieldbus communication network, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, Execute the computer program to: Fill the data bits into the data segment of a signal frame; Fill the unused bits with a set value pattern into the portion of the data segment that is not filled with the data bits; and The data segment is encapsulated to generate the signal frame. The value selection mode is set such that: a) The values ​​of the unused bits that are filled have a periodicity; and b) When the signal frame is transmitted, at least one component of the electromagnetic radiation frequency associated with the periodicity is less than a set threshold.

8. The apparatus of claim 7, wherein, The signal frame is a CAN frame or a CAN-FD frame.

9. The apparatus of claim 8, wherein, The values ​​of the unused bits that are filled within a byte are periodic.

10. The apparatus of claim 9, wherein, The unused bits that are filled are repeated within a byte at a period greater than 1.

11. The apparatus of claim 9, wherein, The value pattern is one of the following: "11001100", "00110011", "10101010", and "01010101".

12. The apparatus of claim 10, wherein, The at least one electromagnetic radiation frequency associated with the periodicity is determined as follows: Among them, f n Where n is the electromagnetic radiation frequency, n is a natural number greater than or equal to 1, Bund_rate is the transmission rate of the CAN frame or CAN-FD frame, and N is the period of repetition of the filled bits within one byte.

13. A computer-readable storage medium storing a computer program thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-6.

14. A method for decoding signals transmitted in a fieldbus communication network, comprising the following steps: Receive a signal frame encoded using the method described in any one of claims 1-6; Extracting data segments from the signal frame; and The data bits are obtained by identifying unused bits based on the value pattern.

15. An apparatus for decoding signals transmitted in a fieldbus communication network, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, Execute the computer program to: Receive a signal frame generated by the apparatus according to any one of claims 7-12; Extracting data segments from the signal frame; and The data bits are obtained by identifying unused bits based on the value pattern.

16. A computer-readable storage medium storing a computer program thereon, characterized in that, When the computer program is executed by the processor, it implements the method as described in claim 14.

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