A system based on single-fiber CAN communication optical network

Abstract

The utility model relates to a system based on a single-fiber CAN communication optical network, including a host and at least one slave, the host includes a first controller, a first photoelectric transceiver module, and a first signal conversion module, and the slave includes a second controller, a second photoelectric transceiver module, and a second signal conversion module; the first photoelectric transceiver module is connected to the second photoelectric transceiver module through a single optical fiber; the first controller is connected to the first photoelectric transceiver module, and the first controller is also connected to the first photoelectric transceiver module through the first signal conversion module; the second photoelectric transceiver module is connected to the second controller through the second signal conversion module. The utility model realizes two-way communication of a single optical fiber in a CAN communication network, while reducing communication costs.

Description

Technical Field

[0001] The utility model relates to the technical field of optical network communication, in particular to a system based on a single-fiber CAN communication optical network. Background Art

[0002] With the development of information technology, optical network communication technology has been widely used in various fields. However, in the implementation process of traditional CAN communication network, due to the limitations of transmission media and communication protocols, multiple optical fibers are usually required for data transmission, which undoubtedly increases the communication cost and complexity. Therefore, based on the protocol of CAN communication network, it is an urgent problem to realize single optical fiber communication and reduce production costs at the same time.

[0003] Existing solution CN113840189A-A vehicle CAN network fiber optic system based on passive optical network, such as Figure 1 As shown, a vehicle controller and a fiber optic transceiver are disclosed, wherein the vehicle controller is connected to the fiber optic transceiver via an optical fiber, and the fiber optic transceiver is connected to the fiber optic distribution network via an optical fiber, and its function is to obtain the bus status belonging to all CAN nodes, and then send the bus status of the CAN node to the corresponding node, and the vehicle controller node receives the uplink signal transmitted by the CAN node through the fiber optic distribution network, and converts it into a downlink signal, which is broadcast to all CAN nodes through the fiber optic distribution network to complete the transmission of the CAN signal. However, this solution requires the use of a CAN communication IC chip to be implemented, which is costly. Utility Model Content

[0004] The utility model aims to realize bidirectional communication of a single optical fiber, reduce communication costs, and provide a system based on a single-fiber CAN communication optical network.

[0005] In order to achieve the above-mentioned utility model object, the utility model embodiment provides the following technical solutions:

[0006] A system based on a single-fiber CAN communication optical network, comprising a host and at least one slave;

[0007] The host includes a first controller, a first optoelectronic transceiver module, and a first signal conversion module, and the slave includes a second controller, a second optoelectronic transceiver module, and a second signal conversion module;

[0008] The first optoelectronic transceiver module and the second optoelectronic transceiver module are communicatively connected via a single optical fiber;

[0009] The first controller sends an electrical signal to the first optoelectronic transceiver module and the first signal conversion module at the same time. At the same time, the first optoelectronic transceiver module receives the optical signal of the second optoelectronic transceiver module, converts the optical signal into an electrical signal, and sends it to the first signal conversion module. The first signal conversion module flips the electrical signal and performs a logic operation with the electrical signal sent by the first controller to obtain a first input signal. The first controller receives the first input signal.

[0010] The second optoelectronic transceiver module receives the optical signal of the first optoelectronic transceiver module, converts the optical signal into an electrical signal and sends it to the second signal conversion module. The second signal conversion module performs a logical operation on the optical signal and the electrical signal sent by the second controller to obtain a second input signal. The second controller receives the second input signal. At the same time, the electrical signal sent by the second controller is flipped by the second signal conversion module and sent to the second optoelectronic transceiver module.

[0011] In the above scheme, one-to-one or one-to-many CAN single optical fiber bidirectional communication between the host and the slaves is realized, and the traditional CAN communication IC chip is removed to save costs.

[0012] Furthermore, the first signal conversion module includes a first reverse direction unit and a first same direction unit;

[0013] The output end of the first optoelectronic transceiver module is connected to the input end of the first reverse unit, the output end of the first reverse unit is connected to the input end of the first unidirectional unit, the output end of the first unidirectional unit is connected to the input end of the first controller, and the output end of the first controller is respectively connected to the input end of the first optoelectronic transceiver module and the input end of the first unidirectional unit;

[0014] The first controller sends an electrical signal to the first optoelectronic transceiver module;

[0015] The first optoelectronic transceiver module converts the optical signal received from other slaves into an electrical signal and sends it to the first reverse unit. The first reverse unit flips the electrical signal and sends it to the first unidirectional unit. The first unidirectional unit performs a logical operation on the flipped electrical signal and the electrical signal sent by the first controller to the first optoelectronic transceiver module to obtain a first input signal. The first unidirectional unit sends the first input signal to the first controller.

[0016] As an implementation method, the first inverting unit is a NOT gate, and the first same-direction unit is an AND gate.

[0017] As another possible implementation mode, the first inverting unit is a MOS tube, and the first inverting unit is an AND gate.

[0018] Furthermore, the second signal conversion module includes a second same direction unit and a second reverse direction unit;

[0019] The output end of the second optoelectronic transceiver module is connected to the input end of the second same-direction unit, the output end of the second same-direction unit is connected to the input end of the second controller, the output end of the second controller is respectively connected to the input end of the second reverse unit and the input end of the second same-direction unit, and the output end of the second reverse unit is connected to the input end of the second optoelectronic transceiver module;

[0020] The second controller sends an electrical signal to the second reverse unit, and the second reverse unit flips the electrical signal and sends it to the second optoelectronic transceiver module;

[0021] The second optoelectronic transceiver module converts the optical signal received from the host into an electrical signal and sends it to the second unidirectional unit. The second unidirectional unit performs a logical operation on the electrical signal sent by the second optoelectronic transceiver module and the electrical signal sent by the second controller to the second reverse unit to obtain a second input signal. The second unidirectional unit sends the second input signal to the second controller.

[0022] As an implementation method, the second inverting unit is a NOT gate, and the second same-direction unit is an AND gate.

[0023] As another possible implementation mode, the second inverting unit is a MOS tube, and the second inverting unit is an AND gate.

[0024] In the above solution, the first inverting unit and the second inverting unit are preferably NOT gates, because the GS of the MOS tube has a junction capacitance which will produce a certain delay when it is turned on.

[0025] Furthermore, it also includes a splitter, and the first optoelectronic transceiver module is communicatively connected to multiple second optoelectronic transceiver modules through the splitter. The first optoelectronic transceiver module and the splitter are connected by a single optical fiber, and each of the second optoelectronic transceiver modules is connected to the splitter by a single optical fiber.

[0026] In the above scheme, a splitter is used to replace multiple repeaters in traditional optical fibers. As long as the slave address is set correctly, it is only necessary to plug the optical fiber into the splitter to achieve communication with multiple slaves. There is no need to use transceivers and other equipment for signal conversion on the slave end, which further saves costs.

[0027] Compared with the prior art, the utility model has the following beneficial effects: the utility model uses a unidirectional unit and a reverse unit to realize the signal logic processing function, realizes the communication of a single optical fiber in the CAN communication network, and reduces the CAN communication IC chip to reduce the cost. The circuit implementation principle is simple, and the overall cost of the system is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the prior art in the background technology;

[0030] Figure 2 This is a system block diagram of the utility model;

[0031] Figure 3 This is the schematic diagram of the host circuit of the utility model;

[0032] Figure 4 This is the schematic diagram of the slave circuit of the utility model;

[0033] Figure 5 This is a schematic diagram of signal trends in Example 2 of the utility model;

[0034] Figure 6 This is a system block diagram of Example 3 of the utility model. DETAILED DESCRIPTION

[0035] The technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the utility model.

[0036] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present utility model, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance, or implying any such actual relationship or order between these entities or operations. Example 1

[0037] The utility model is realized by the following technical solutions: Figure 2As shown, a system based on a single-fiber CAN communication optical network includes a host and at least one slave; the host includes a first controller, a first optoelectronic transceiver module, and a first signal conversion module, and the slave includes a second controller, a second optoelectronic transceiver module, and a second signal conversion module. In an implementable manner, the first optoelectronic transceiver module and the second optoelectronic transceiver module are connected to each other through a single optical fiber; the first controller simultaneously sends an electrical signal to the first optoelectronic transceiver module and the first signal conversion module, and at the same time, the first optoelectronic transceiver module receives the optical signal of the second optoelectronic transceiver module, converts the optical signal into an electrical signal and sends it to the first signal conversion module, the first signal conversion module flips the electrical signal and performs a logical operation with the electrical signal sent by the first controller to obtain a first input signal, and the first controller receives the first input signal; the second optoelectronic transceiver module receives the optical signal of the first optoelectronic transceiver module, converts the optical signal into an electrical signal and sends it to the second signal conversion module, the second signal conversion module performs a logical operation with the electrical signal sent by the second controller to obtain a second input signal, and the second controller receives the second input signal, and at the same time, the electrical signal sent by the second controller is flipped by the second signal conversion module and sent to the second optoelectronic transceiver module.

[0038] Furthermore, the first signal conversion module includes a first reverse unit and a first unidirectional unit; the output end of the first photoelectric transceiver module is connected to the input end of the first reverse unit, the output end of the first reverse unit is connected to the input end of the first unidirectional unit, the output end of the first unidirectional unit is connected to the input end of the first controller, and the output end of the first controller is respectively connected to the input end of the first photoelectric transceiver module and the input end of the first unidirectional unit. The first controller sends an electrical signal to the first photoelectric transceiver module; the first photoelectric transceiver module converts the optical signal received from other slaves into an electrical signal and sends it to the first reverse unit, the first reverse unit flips the electrical signal and sends it to the first unidirectional unit, the first unidirectional unit performs a logic operation on the flipped electrical signal and the electrical signal sent by the first controller to the first photoelectric transceiver module to obtain a first input signal, and the first unidirectional unit sends the first input signal to the first controller.

[0039] In one embodiment, see Figure 3 The schematic diagram of the circuit principle of the host is shown in FIG. 2 , wherein the first reverse unit is a NOT gate N1, and the first unidirectional unit is an AND gate U1; the RD pin of the first optoelectronic transceiver module is connected to the input of the NOT gate N1, and the output of the NOT gate N1 is connected to the input of the AND gate U1; the output of the first controller is respectively connected to the input of the AND gate U1 and the TD pin of the first optoelectronic transceiver module.

[0040] In another embodiment, the first reverse unit is a MOS tube, and the first in-direction unit is an AND gate; the RD pin of the first optoelectronic transceiver module is connected to the gate of the MOS tube, and the drain of the MOS tube is connected to the input end of the AND gate; the output end of the first controller is respectively connected to the input end of the AND gate and the TD pin of the first optoelectronic transceiver module.

[0041] Furthermore, the second signal conversion module includes a second unidirectional unit and a second reverse unit; the output end of the second photoelectric transceiver module is connected to the input end of the second unidirectional unit, the output end of the second unidirectional unit is connected to the input end of the second controller, the output end of the second controller is respectively connected to the input end of the second reverse unit and the input end of the second unidirectional unit, and the output end of the second reverse unit is connected to the input end of the second photoelectric transceiver module. The second controller sends an electrical signal to the second reverse unit, and the second reverse unit flips the electrical signal and sends it to the second photoelectric transceiver module; the second photoelectric transceiver module converts the optical signal sent by the host into an electrical signal and sends it to the second unidirectional unit, the second unidirectional unit performs a logical operation on the electrical signal sent by the second photoelectric transceiver module and the electrical signal sent by the second controller to the second reverse unit to obtain a second input signal, and the second unidirectional unit sends the second input signal to the second controller.

[0042] In one embodiment, see Figure 4 Schematic diagram of the circuit principle of the slave, the second reverse unit is a MOS tube M2, the second in-direction unit is an AND gate U2; the RD pin of the second photoelectric transceiver module is connected to the input end of the AND gate U2, the output end of the second controller is respectively connected to the input end of the AND gate U2 and the gate of the MOS tube M2, the output end of the AND gate U2 is connected to the input end of the second controller, and the drain of the MOS tube M2 is connected to the TD pin of the second photoelectric transceiver module.

[0043] In another embodiment, the second inverting unit is a NOT gate, and the second in-direction unit is an AND gate; the RD pin of the second optoelectronic transceiver module is connected to the input of the AND gate, the output of the second controller is respectively connected to the input of the AND gate and the input of the NOT gate, the output of the AND gate is connected to the input of the second controller, and the output of the NOT gate is connected to the TD pin of the second optoelectronic transceiver module. Example 2

[0044] This embodiment provides an practicable signal trend description based on the above embodiment 1, such as Figure 5 As shown, according to the CAN communication protocol, when there is data transmission, the signal is high and low level, and when there is no data transmission, the signal is always high level. Usually, the host first controller sends data first. The dotted arrows and corresponding numbers indicate the order of data flow:

[0045] 1. The CANTX pin of the first controller sends data, and the output signal TX1 is simultaneously transmitted to the input end of the first unidirectional unit and the TD pin of the first photoelectric transceiver module. At this time, since the RD pin of the first photoelectric transceiver module has no data output, the signal RD1 is at a low level. RD1 is flipped to a high level after passing through the first reverse unit, so the level of the signal RX4 output by the first unidirectional unit is the same as the level of the signal TX1;

[0046] 2. The first optoelectronic transceiver module converts the signal TX1 into an optical signal and sends it to the second optoelectronic transceiver module through a single optical fiber;

[0047] 3. The second photoelectric transceiver module converts the received optical signal into an electrical signal RD2 and sends it to the second unidirectional unit. The RD pin of the second photoelectric transceiver module sends data, and the electrical signal RD2 is high and low level. At this time, since the CANTX pin of the second controller has no data to send, the signal TX2 is high level, so the level of the signal RX2 output by the second unidirectional unit is the same as the level of the signal RD2;

[0048] 4. The second unidirectional unit converts the electrical signal RD2 into a signal RX2 and sends it to the CANRX pin of the second controller;

[0049] 5. Based on the signal RX2, the second controller feeds back the output signal TX2 to the second same-direction unit and the second reverse unit. The CANTX pin of the second controller sends data, and the signal TX2 is high and low level. At this time, because the data has reached the line with sequence number 5, the signal RD2 on the line with sequence number 3 has no data, that is, the signal RD2 is high level, so the level of the signal RX2 output by the second same-direction unit is the same as the level of the signal TX2; after the second same-direction unit performs a logic operation on the signal RD2 and the signal TX2, it outputs the signal RX2 to the second controller;

[0050] 6. The second inverting unit flips the signal TX2 into the signal TD1 and sends it to the second optoelectronic transceiver module;

[0051] 7. The second optoelectronic transceiver module converts the signal TD1 into an optical signal and transmits it to the first optoelectronic transceiver module through a single optical fiber;

[0052] 8. The first optoelectronic transceiver module converts the received optical signal into an electrical signal RD1 and sends it to the first reverse unit. At this time, the electrical signal RD1 is at a high or low level, and the signal RX1 after being flipped by the first reverse unit is still at a high or low level;

[0053] 9. The first reverse unit flips the electrical signal RD1 into a signal RX1 and sends it to the first same-direction unit;

[0054] 10. After the first isodirectional unit performs a logic operation on the signal RX1 and the signal TX1, it outputs the signal RX4 to the first controller. The signal RX1 is at a high-low level, but the signal TX1 is at a high level at this time, so the level of the signal RX4 output by the first isodirectional unit is the same as the level of the signal RX1. Example 3

[0055] The difference between this embodiment and embodiment 1 is that Figure 6 As shown, it also includes a splitter, the first optoelectronic transceiver module is communicatively connected to multiple second optoelectronic transceiver modules through the splitter, the first optoelectronic transceiver module and the splitter are connected by a single optical fiber, and each of the second optoelectronic transceiver modules and the splitter are connected by a single optical fiber.

[0056] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A system based on a single-fiber CAN communication optical network, comprising a host and at least one slave, characterized in that: The host includes a first controller, a first optoelectronic transceiver module, and a first signal conversion module, and the slave includes a second controller, a second optoelectronic transceiver module, and a second signal conversion module; The first optoelectronic transceiver module and the second optoelectronic transceiver module are communicatively connected via a single optical fiber; The first controller sends an electrical signal to the first optoelectronic transceiver module and the first signal conversion module at the same time. At the same time, the first optoelectronic transceiver module receives the optical signal of the second optoelectronic transceiver module, converts the optical signal into an electrical signal, and sends it to the first signal conversion module. The first signal conversion module flips the electrical signal and performs a logic operation with the electrical signal sent by the first controller to obtain a first input signal. The first controller receives the first input signal. The second optoelectronic transceiver module receives the optical signal of the first optoelectronic transceiver module, converts the optical signal into an electrical signal and sends it to the second signal conversion module. The second signal conversion module performs a logical operation on the optical signal and the electrical signal sent by the second controller to obtain a second input signal. The second controller receives the second input signal. At the same time, the electrical signal sent by the second controller is flipped by the second signal conversion module and sent to the second optoelectronic transceiver module.

2. A system based on a single-fiber CAN communication optical network according to claim 1, characterized in that: The first signal conversion module includes a first reverse direction unit and a first same direction unit; The output end of the first optoelectronic transceiver module is connected to the input end of the first reverse unit, the output end of the first reverse unit is connected to the input end of the first unidirectional unit, the output end of the first unidirectional unit is connected to the input end of the first controller, and the output end of the first controller is respectively connected to the input end of the first optoelectronic transceiver module and the input end of the first unidirectional unit; The first controller sends an electrical signal to the first optoelectronic transceiver module; The first optoelectronic transceiver module converts the optical signal received from other slaves into an electrical signal and sends it to the first reverse unit. The first reverse unit flips the electrical signal and sends it to the first unidirectional unit. The first unidirectional unit performs a logical operation on the flipped electrical signal and the electrical signal sent by the first controller to the first optoelectronic transceiver module to obtain a first input signal. The first unidirectional unit sends the first input signal to the first controller.

3. A system based on a single-fiber CAN communication optical network according to claim 2, characterized in that: The first inverting unit is a NOT gate, and the first same-direction unit is an AND gate.

4. A system based on a single-fiber CAN communication optical network according to claim 2, characterized in that: The first reverse unit is a MOS tube, and the first non-reciprocating unit is an AND gate.

5. The system based on a single-fiber CAN communication optical network according to claim 1, characterized in that: The second signal conversion module includes a second same direction unit and a second reverse direction unit; The output end of the second optoelectronic transceiver module is connected to the input end of the second same-direction unit, the output end of the second same-direction unit is connected to the input end of the second controller, the output end of the second controller is respectively connected to the input end of the second reverse unit and the input end of the second same-direction unit, and the output end of the second reverse unit is connected to the input end of the second optoelectronic transceiver module; The second controller sends an electrical signal to the second reverse unit, and the second reverse unit flips the electrical signal and sends it to the second optoelectronic transceiver module; The second optoelectronic transceiver module converts the optical signal received from the host into an electrical signal and sends it to the second unidirectional unit. The second unidirectional unit performs a logical operation on the electrical signal sent by the second optoelectronic transceiver module and the electrical signal sent by the second controller to the second reverse unit to obtain a second input signal. The second unidirectional unit sends the second input signal to the second controller.

6. A system based on a single-fiber CAN communication optical network according to claim 5, characterized in that: The second inverting unit is a NOT gate, and the second same-direction unit is an AND gate.

7. The system based on single-fiber CAN communication optical network according to claim 5, characterized in that: The second inverting unit is a MOS tube, and the second inverting unit is an AND gate.

8. A system based on a single-fiber CAN communication optical network according to any one of claims 1 to 7, characterized in that: It also includes a splitter, the first optoelectronic transceiver module is communicatively connected to multiple second optoelectronic transceiver modules through the splitter, the first optoelectronic transceiver module is connected to the splitter with a single optical fiber, and each of the second optoelectronic transceiver modules is connected to the splitter with a single optical fiber.

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