Optocoupler-isolated self-adaptive multi-level unidirectional data transmission device

Abstract

The invention relates to the technical field of communication, in particular to an optical coupler isolation adaptive multi-level one-way data transmission device. Comprising a sending module, an information isolation transmission channel and a receiving module which are connected in sequence. Wherein the information isolation transmission channel is a one-way transmission module based on an optocoupler structure; in the output transmission process, the level number of the triode collector voltage is a natural number larger than 2. Compared with a general data transmission environment and a general transmission method, the transmission method provided by the invention is applied to the transmission device provided by the invention, and the rate and stability of unidirectional information transmission can be effectively improved under the condition of no information feedback.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to an optocoupler-isolated adaptive multi-level unidirectional data transmission device. Background Art

[0002] When performing unidirectional data transmission between different networks with strict isolation requirements, it is necessary to simultaneously meet the requirements of high electrical isolation, high communication rate, high reliability, and low interception, while also taking into account cost factors. As a unidirectional communication isolation device, high-speed optical couplers have significant advantages of low leakage and low interception compared to traditional isolation methods such as unidirectional optical fibers and magnetic coupling devices. They can achieve complete electrical isolation including the ground network, and have both isolation performance and cost advantages, but they have disadvantages in communication performance such as rate and reliability. Summary of the invention

[0003] In order to solve the problem of improving the communication rate and communication reliability during the communication process when an optical coupler is used as an isolation device, the present invention proposes an adaptive multi-level unidirectional data transmission device with optical coupler isolation.

[0004] An adaptive multi-level unidirectional data transmission device with optical coupling isolation includes a transmitting module, an information isolation transmission channel, and a receiving module connected in sequence; wherein the information isolation transmission channel is a unidirectional transmission module based on an optical coupling structure; specifically, the optical coupling structure includes a light emitting diode and a receiving transistor, and the receiving transistor works in an amplification region;

[0005] During the output transmission process, the sending module encodes the target data to be transmitted and sends a corresponding signal to the light-emitting diode, so that the light-emitting diode emits light of corresponding brightness, thereby causing the collector of the receiving transistor to generate a corresponding voltage. The receiving module detects the voltage of the collector of the receiving transistor through the AD circuit to obtain the corresponding data. The receiving module then decodes the data to obtain the target data; wherein, the level number of the transistor collector voltage is M, where , k is a natural number greater than 1.

[0006] Preferably, the signal sent by the sending module to the light emitting diode is a PWM signal.

[0007] Preferably, the receiving module detects the voltage of the collector of the receiving transistor through the AD circuit, and the process of obtaining the corresponding data is as follows:

[0008] The transistor collector voltage is sampled, interference is filtered out by a digital low-pass filter, and then symbol segmentation is performed through a waveform mutation detection algorithm and an adaptive threshold detection algorithm to obtain the segmented symbol level, and then the symbol level is converted into corresponding data according to the symbol level standard voltage.

[0009] Preferably, the symbol level standard voltage is dynamically adjusted regularly according to the actually collected statistical data of the symbol level.

[0010] Preferably, the sending module performs encoding in the following manner:

[0011] The target data is grouped into (Log2M)-1 bits each, and an adjustment code is added to each group of data to obtain the encoded target data. The value of the adjustment code makes the encoded target data satisfy the following: the contents of any two consecutive groups of data are inconsistent;

[0012] The receiving module decodes in the following way:

[0013] Delete the adjustment code in each set of data to obtain the target data.

[0014] Beneficial effects:

[0015] (1) Using optocouplers as isolation devices can achieve complete electrical isolation including the ground network, greatly improving the isolation level;

[0016] (2) The triode of the optocoupler device works in the linear amplification region to achieve multi-level modulation, which improves the efficiency of information transmission;

[0017] (3) By adding the level adjustment bit, the transmission level can be changed. The receiving side can implement adaptive symbol segmentation, avoiding dependence on the transmission baud rate and improving the stability and reliability of information transmission.

[0018] (4) Demodulation is performed by AD sampling, which preserves the integrity of symbol information to the greatest extent, and can realize active error correction of one-way information transmission, greatly improving the stability of the system and the accuracy of information;

[0019] (5) Dynamically implement symbol level calibration to reduce the dependence of symbol information on level, making the system insensitive to component accuracy, optical coupler characteristic differences, and ambient temperature changes, thereby reducing device costs and improving system stability;

[0020] (6) Using digital processing algorithms to detect symbol levels can effectively reduce the cost of the device.

[0021] (7) Compared with the general data transmission environment and the general transmission method, the transmission method proposed in the present invention is applied to the proposed transmission device, which can effectively improve the rate and stability of one-way information transmission without information feedback. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a principle block diagram of a one-way data transmission device with optical coupling isolation in an embodiment of the present invention;

[0023] Figure 2 It is an eight-symbol level reference diagram in an embodiment of the present invention;

[0024] Figure 3 This is an ideal transmission waveform diagram in an embodiment of the present invention;

[0025] Figure 4 This is a waveform diagram of actual sampling in an embodiment of the present invention;

[0026] Figure 5 An adaptive symbol detection diagram in an embodiment of the present invention;

[0027] Figure 6 This is a symbol level calibration diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figure 1 As shown, an adaptive multi-level unidirectional data transmission device with optical coupling isolation includes a sending module, an information isolation transmission channel, and a receiving module connected in sequence; wherein the information isolation transmission channel is a unidirectional transmission module based on an optical coupling structure; specifically, the optical coupling structure includes a light emitting diode and a receiving transistor, and the receiving transistor works in an amplification region;

[0030] During the output transmission process, the sending module encodes the target data to be transmitted and sends a corresponding signal to the light-emitting diode, so that the light-emitting diode emits light of corresponding brightness, thereby causing the collector of the receiving transistor to generate a corresponding voltage. The receiving module detects the voltage of the collector of the receiving transistor through the AD circuit to obtain the corresponding data. The receiving module then decodes the data to obtain the target data; wherein, the level number of the transistor collector voltage is M, where , k is a natural number greater than 1.

[0031] In a further embodiment, the signal sent by the sending module to the light emitting diode is a PWM signal;

[0032] The receiving module detects the voltage of the collector of the receiving transistor through the AD circuit, and the process of obtaining the corresponding data is as follows:

[0033] The transistor collector voltage is sampled, interference is filtered out by a digital low-pass filter, and then symbol segmentation is performed by a waveform mutation detection algorithm and an adaptive threshold detection algorithm to obtain the segmented symbol level, and then the symbol level is converted into corresponding data according to the symbol level standard voltage; in a further implementation scheme, the symbol level standard voltage is dynamically adjusted regularly according to the statistical data of the symbol level actually collected;

[0034] In some implementations, the sending module performs encoding in the following manner:

[0035] The target data is grouped into (Log2M)-1 bits each, and an adjustment code is added to each group of data to obtain the encoded target data. The value of the adjustment code makes the encoded target data satisfy the following: the contents of any two consecutive groups of data are inconsistent;

[0036] The receiving module decodes in the following way:

[0037] Delete the adjustment code in each set of data to obtain the target data.

[0038] The following describes the transmission process in more detail:

[0039] In this embodiment, the level number M is 8, and the target data to be transmitted is 0x5A.

[0040] First, group the target data into groups of 2 bits each, and get 01, 01, 10, 10;

[0041] An adjustment code is added to each group, and the default value of the adjustment code is 0, resulting in 010, 010, 100, 100; in order to make the contents of any two consecutive groups of data inconsistent, the adjustment codes of the first and third groups are inverted, and the encoded target data is: 011, 010, 101, 100; thereby ensuring that the symbol levels corresponding to adjacent groups change, which is conducive to the subsequent adaptive symbol segmentation according to the transmission level.

[0042] In this embodiment, there are 8 symbol level standard voltages. Initially, the symbol level standard voltages are as follows: Figure 2 As shown, the ideal symbol level received by the receiving module should be as follows Figure 3 However, due to the nonlinearity of the optical coupler, as well as factors such as modulation error, channel interference and sampling quantization error, the actual sampled waveform is as follows Figure 4 As shown, the waveform mutation detection algorithm is then used to obtain Figure 5 The waveform shown in the figure is then symbol-segmented using an adaptive threshold detection algorithm, and the symbol-level standard voltage is compared to obtain the data 011, 010, 101, 100. The last bit of each group of data, i.e., the adjustment code, is deleted to obtain the target data 01, 01, 10, 10, i.e., 0x5A.

[0043] like Figure 5 As shown, red represents the reference level, and blue represents the sampling level. It is found that the center level will be offset. This offset may migrate with the change of ambient temperature. Therefore, the present invention proposes to dynamically adjust the symbol level standard voltage regularly based on the statistical data of the symbol level obtained by actual sampling.

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An adaptive multi-level unidirectional data transmission device with optical coupling isolation, characterized in that: It includes a sending module, an information isolation transmission channel, and a receiving module connected in sequence; wherein the information isolation transmission channel is a unidirectional transmission module based on an optical coupling structure; specifically, the optical coupling structure includes a light emitting diode and a receiving transistor, and the receiving transistor works in an amplification region; During the output transmission process, the sending module encodes the target data to be transmitted and sends a corresponding signal to the light-emitting diode, so that the light-emitting diode emits light of corresponding brightness, thereby causing the collector of the receiving transistor to generate a corresponding voltage. The receiving module detects the voltage of the collector of the receiving transistor through the AD circuit to obtain the corresponding data. The receiving module then decodes the data to obtain the target data; wherein, the level number of the transistor collector voltage is M, where , k is a natural number greater than 1.

2. The optically-coupled, self-adaptive multi-level unidirectional data transmission device according to claim 1, characterized in that: The signal sent by the sending module to the light emitting diode is a PWM signal.

3. The optically-coupled, self-adaptive multi-level unidirectional data transmission device according to claim 1, characterized in that: The receiving module detects the voltage of the collector of the receiving transistor through the AD circuit, and the process of obtaining the corresponding data is as follows: The transistor collector voltage is sampled, interference is filtered out by a digital low-pass filter, and then symbol segmentation is performed through a waveform mutation detection algorithm and an adaptive threshold detection algorithm to obtain the segmented symbol level, and then the symbol level is converted into corresponding data according to the symbol level standard voltage.

4. The optically-coupled, self-adaptive multi-level unidirectional data transmission device according to claim 3, characterized in that: The symbol level standard voltage is dynamically adjusted regularly based on the actually collected statistical data of the symbol level.

5. The optically-coupled, isolated, adaptive multi-level unidirectional data transmission device according to claim 1, characterized in that: The sending module encodes in the following way: The target data is grouped into (Log2M)-1 bits each, and an adjustment code is added to each group of data to obtain the encoded target data. The value of the adjustment code makes the encoded target data satisfy the following: the contents of any two consecutive groups of data are inconsistent; The receiving module decodes in the following way: Delete the adjustment code in each set of data to obtain the target data.

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