Imaging system with high electromagnetic compatibility performance

Abstract

The present invention relates to the technical field of imaging systems, and in particular to an imaging system with high electromagnetic compatibility performance, comprising a distributor, a linear array focal plane group, an area array focal plane group, an imaging processor group, a laser group, and a controller. The distributor receives an external primary power supply and provides independent secondary power supply to each device. The housing of each device is connected to the shielded ground of its corresponding cable, and the housing of each device is connected to the cabin. The secondary ground inside the distributor and the secondary ground inside the laser group are not connected to their respective housings. The secondary ground inside the linear array focal plane group, the secondary ground inside the area array focal plane group, the secondary ground inside the imaging processor group, and the secondary ground inside the controller are all crimped to their respective housings via a copper-plated grounding method. The present invention can improve the electromagnetic compatibility performance of the imaging system and avoid mutual interference between the various components within the imaging system.

Description

Technical Field

[0001] The present invention belongs to the technical field of imaging systems, and in particular relates to an imaging system with high electromagnetic compatibility. Background Art

[0002] Imaging systems are typically designed as floating ground systems. The housings of each device within the system are connected to the shield ground of the corresponding cable, but the shield grounds of each cable are not directly connected to the signal ground. Instead, all shield grounds on each cable are connected to the signal ground at a single point. With increasing operating frequencies and faster transmission rates, signals exceeding 1 GHz are beginning to appear in imaging systems, necessitating multi-point grounding for each high-frequency device. The housings of each high-frequency device are connected to the shield ground of the corresponding cable, while the shield grounds of each cable are also directly connected to the signal ground. While all high-frequency device housings are connected to the signal ground, they are also connected to each other via a secondary equipotential signal. The housings of each high-frequency device are connected to the cabin, and the power supply provides power to each high-frequency device. In addition to providing a secondary return line, the power supply also outputs telemetry voltage and a telemetry return line. This can cause shunting of the return currents of the power supply circuits, leading to mutual interference between components within the imaging system. Summary of the Invention

[0003] In view of this, the present invention aims to provide an imaging system with high electromagnetic compatibility to solve the problem of mutual interference between various parts of the imaging system caused by multi-point grounding of various high-frequency devices.

[0004] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0005] An imaging system with high electromagnetic compatibility performance includes a power distributor, a linear array focal plane group, an area array focal plane group, an imaging processor group, a laser group and a controller; wherein the power distributor receives a primary power supply input from an external source and provides an independent secondary power supply for the linear array focal plane group, the area array focal plane group, the imaging processor group and the controller; the controller communicates with the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group respectively and receives telemetry signals returned by the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group; the controller controls the power distributor to turn on and off the power of the linear array focal plane group, the area array focal plane group and the imaging processor group; The casing of the device, the casing of the linear array focal plane group, the casing of the area array focal plane group, the casing of the imaging processor group, the casing of the laser group, and the casing of the controller are all connected to the shielded ground of their corresponding cables. At the same time, the casing of the power distributor, the casing of the linear array focal plane group, the casing of the area array focal plane group, the casing of the imaging processor group, the casing of the laser group, and the casing of the controller are all connected to the cabin panel; the secondary ground inside the power distributor and the secondary ground inside the laser group are not connected to their own casings; the secondary ground inside the linear array focal plane group, the secondary ground inside the area array focal plane group, the secondary ground inside the imaging processor group, and the secondary ground inside the controller are all crimped to their own casings through copper grounding.

[0006] Furthermore, an isolation transformer is used inside the distributor to isolate the external input primary power supply from the output secondary power supply, and independently provide secondary power supply for the linear array focal plane group, the area array focal plane group, the imaging processor group and the controller. The power supply of the linear array focal plane group, the power supply of the area array focal plane group, the power supply of the imaging processor group and the power supply of the controller are not connected inside the distributor, and the secondary return line of the linear array focal plane group, the secondary return line of the area array focal plane group, the secondary return line of the imaging processor group, the secondary return line of the laser group and the secondary return line of the controller are not connected inside the distributor.

[0007] Furthermore, telemetry signals returned to the controller by the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group are transmitted using a photoelectric isolation device.

[0008] Furthermore, the optoelectronic isolation device includes a matching optoelectronic transmitting device and an optoelectronic receiving device. The linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group respectively send their respective telemetry signals through independent optoelectronic transmitting devices, and the controller receives each telemetry signal through the optoelectronic receiving device corresponding to each optoelectronic transmitting device.

[0009] Furthermore, the secondary ground inside the laser group is not connected to the secondary ground inside the controller.

[0010] Furthermore, the controller includes a control logic circuit and a focus motor; wherein,

[0011] One connection method between the control logic circuit and the focus motor is as follows: the signal of the control logic circuit and the signal of the focus motor are transmitted using a photoelectric isolation device, and the secondary ground inside the control logic circuit and the secondary ground inside the focus motor are not connected;

[0012] Another way to connect the control logic circuit and the focusing motor is: the signal of the control logic circuit is connected to the signal of the focusing motor for transmission, the secondary ground inside the control logic circuit is connected to the secondary ground inside the focusing motor, and focusing and imaging work in a time-sharing manner.

[0013] Furthermore, the secondary loop in the distributor that supplies power to the linear array focal plane group, the area array focal plane group, the imaging processor group, the laser group and the controller is connected to the secondary ground inside the controller through a series resistor.

[0014] Furthermore, the resistance of the series resistor Select by:

[0015] ;

[0016] Where R is the resistance of the secondary circuit in the distributor. is the noise voltage threshold for stable signal transmission, is the inductive reactance of the transmission line, and I is the maximum current value in the secondary return current of the linear array focal plane group, area array focal plane group, imaging processor group, laser group and controller.

[0017] Furthermore, the key signals output by the controller are driven by the OC gate drive circuit, and the key signals are connected to their respective secondary power supplies using pull-up resistors at the linear array focal plane group, area array focal plane group, and imaging processor group ends. At the same time, the key signals are connected to their respective internal secondary grounds using grounding capacitors at the linear array focal plane group, area array focal plane group, and imaging processor group ends.

[0018] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0019] (1) The housings of the power distributor, linear array focal plane group, area array focal plane group, imaging processor group, laser group and controller are all connected to the shielded ground of the corresponding cables and to the cabin board; the secondary ground inside the power distributor and laser group is not connected to their own housings; the secondary ground inside the linear array focal plane group, area array focal plane group, imaging processor group and controller is crimped to the housing through the copper grounding method on the circuit board, thereby improving the electromagnetic compatibility performance of the imaging system;

[0020] (2) The telemetry signals from the linear array focal plane group, area array focal plane group, imaging processor group, and laser group back to the controller are transmitted in a photoelectric isolation manner to avoid the conduction interference caused by the signal grounds of the various devices being connected together. This can effectively prevent the laser group with strong interfering pulsating current characteristics from interfering with the signals of other devices.

[0021] (3) For stepper motor focusing devices with interference in the controller, one solution for connecting the control logic circuit and the focusing motor is to use optoelectronic isolation for signal transmission to avoid the signal ground of the control logic circuit and the focusing motor being connected together to cause conduction interference, and the secondary grounds between the control logic circuit and the focusing motor are not connected together; another solution for connecting the control logic circuit and the focusing motor is to directly connect the signal of the control logic circuit and the focusing motor, and the secondary grounds between the control logic circuit and the focusing motor are also connected together, but no imaging is performed during the focusing working stage, and no focusing is performed during the imaging working stage. By adopting a time-sharing working mode of focusing and imaging, interference caused by focusing on imaging is avoided;

[0022] (4) For the possible shunt effect of the telemetry loop inside the distributor, photoelectric isolation or resistance separation is used to suppress or reduce the interference caused by the secondary return shunt;

[0023] (5) Most signals are transmitted in differential form, single-ended signals are transmitted using resistor current limiting, and key signals are transmitted using RC integration circuits to reduce the impact of external interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 1 is a schematic structural diagram of an imaging system with high electromagnetic compatibility according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of a grounding topology structure using photoelectric isolation according to an embodiment of the present invention;

[0027] Figure 3 2. It is a schematic diagram of a grounding topology structure using resistance isolation according to an embodiment of the present invention;

[0028] Figure 4 2 is a schematic structural diagram of an RC integration circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, features defined as "first", "second" and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0032] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0034] like Figure 1-Figure 4As shown, the imaging system with high electromagnetic compatibility performance includes a distributor, a linear array focal plane group, an area array focal plane group, an imaging processor group, a laser group and a controller; wherein the distributor receives an external input primary power supply and provides independent power supply of a secondary power supply to the linear array focal plane group, the area array focal plane group, the imaging processor group and the controller; the laser group independently receives an external input primary power supply and generates a related secondary power supply to power related internal circuits; the controller receives an external input primary power supply and generates a related secondary power supply to power related internal circuits, such as the control logic The controller controls the power supply of the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group respectively, performs relevant timing coordination, and receives the telemetry signals returned by the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group; the controller controls the power on and off of the linear array focal plane group, the area array focal plane group and the imaging processor group by controlling the power distributor; the laser group generates an instantaneous laser pulse, which is projected to the area array focal plane group after reflection to detect the laser footprint.

[0035] In a specific embodiment of the present invention, (1) the distributor adopts the DCDC product of the 510th Institute; (2) the linear array focal plane group and the area array focal plane group adopt the linear array detector and the area array detector of Changguang Chenxin Company and the FPGA chip of Fudan Microelectronics Company; (3) the imaging processor group adopts the FPGA chip of Fudan Microelectronics Company; (4) the laser group adopts the product of Shanghai Institute of Optics and Fine Mechanics; (5) the control logic part of the controller adopts the FPGA of Fudan Microelectronics Company, and the focusing motor adopts a stepping motor.

[0036] The housing of the power distributor, the housing of the linear array focal plane group, the housing of the area array focal plane group, the housing of the imaging processor group, the housing of the laser group, and the housing of the controller are all connected to the shielded ground of their corresponding cables through grounding piles. At the same time, the housings of the power distributor, the housings of the linear array focal plane group, the housings of the area array focal plane group, the housings of the imaging processor group, the housings of the laser group, and the housings of the controller are all connected to the cabin board; the secondary ground inside the power distributor and the secondary ground inside the laser group are not connected to their own housings; the secondary ground inside the linear array focal plane group, the secondary ground inside the area array focal plane group, the secondary ground inside the imaging processor group, and the secondary ground inside the controller are all press-connected to their own housings through a large-area copper grounding method on the circuit board. Through the above arrangement, the electromagnetic compatibility performance of the imaging system is improved.

[0037] In order to prevent the possible shunt effect on the internal telemetry loop of the distributor, photoelectric isolation or resistance isolation is used to suppress or reduce the interference caused by the secondary return shunt.

[0038] Using opto-isolated grounding topology such as Figure 2As shown, the linear array focal plane group contains m independent linear array focal planes, the imaging processor group contains n independent imaging processors, and the area array focal plane group contains q independent area array focal planes. Each linear array focal plane, area array focal plane, and imaging processor is a module. An isolation transformer is used within the power distribution box to isolate the external primary power input from the secondary power output, providing independent power to each module. The power supplies and secondary return lines of each module are not connected within the power distribution box. Telemetry signals from each module to the controller are transmitted via the power distribution box using optoelectronic isolation.

[0039] The photoelectric isolation method is realized through the photoelectric isolation equipment, which includes the matching photoelectric transmitting equipment and photoelectric receiving equipment. The linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group respectively send their respective telemetry signals through independent photoelectric transmitting equipment, and the controller receives each telemetry signal through the photoelectric receiving equipment corresponding to each photoelectric transmitting equipment.

[0040] Low-cost grounding topologies using resistive isolation such as Figure 3 As shown, the power distribution unit and controller are combined into a single electrical box, collectively referred to as the controller. The original controller is called the controller control section, and the original power distribution unit is called the controller power supply and distribution section. The controller power supply and distribution section provides power to all components except the laser group. The linear array focal plane group contains m independent linear array focal planes, the imaging processor group contains n independent imaging processors, and the area array focal plane group contains q independent area array focal planes. Each linear array focal plane, area array focal plane, and imaging processor is a module. The controller power supply and distribution section uses an isolation transformer to isolate the external primary power input from the secondary power output, providing independent power to each module. The power supplies of each module are not connected within the power distribution unit, and the secondary circuits of each module are not connected within the power distribution unit. The secondary circuits within the controller power supply and distribution section, which power each linear array focal plane group, each area array focal plane group, and each imaging processor group, are connected to the secondary ground of the controller control section through series resistors.

[0041] The resistance of the series resistor The choice depends on the maximum current value I in the secondary return of each module, the resistance value R of the secondary return line in the power supply and distribution part of the controller, and the noise voltage threshold for stable signal transmission. , the inductive reactance of the transmission line , as follows:

[0042] .

[0043] For laser groups with pulsating current characteristics that cause strong interference, the telemetry signal of the laser group is optically isolated from the telemetry signals of other devices to avoid conduction interference caused by connecting the signal grounds together. The secondary ground of the laser group is not connected to the secondary ground of the controller.

[0044] For stepper motor focusing devices with interference in the controller, one solution for connecting the control logic circuit and the focusing motor is to transmit the signal of the control logic circuit and the signal of the focusing motor using optoelectronic isolation (implemented by optoelectronic isolation equipment) to avoid conductive interference caused by connecting the signal grounds together, and the secondary ground inside the control logic circuit is not connected to the secondary ground inside the focusing motor; another solution for connecting the control logic circuit and the focusing motor is to transmit the signal of the control logic circuit and the signal of the focusing motor through connection, and the secondary ground inside the control logic circuit is connected to the secondary ground inside the focusing motor, but no imaging is performed during the focusing working stage, and no focusing is performed during the imaging working stage. By adopting a time-sharing working mode of focusing and imaging, interference of focusing on imaging is avoided.

[0045] To prevent the short-circuit faults between devices that may cause large currents and improve anti-interference capabilities, the differential telemetry signals output by the linear array focal plane group, area array focal plane group, and imaging processor group are transmitted in differential form; the single-ended telemetry signals output by the linear array focal plane group, area array focal plane group, and imaging processor group are not directly output through the power supply, but are limited by current in series with a resistor to ensure that the short-circuit current is within the milliampere level when the signal is short-circuited. Figure 4 As shown, the key signals output by the controller (such as the master-slave identification signals) are driven by the OC (open-drain) gate drive circuit. The key signals are connected to the secondary power supply at the linear array focal plane group, the area array focal plane group, and the imaging processor group using pull-up resistors. At the same time, the key signals are connected to the secondary grounds of the linear array focal plane group, the area array focal plane group, and the imaging processor group using grounding capacitors. That is, the key signals are output using an RC integration circuit. In the event of a short circuit, the current limiting effect of the pull-up resistor can ensure that the short-circuit current is at the milliampere level when the signal is short-circuited. At the same time, the grounding capacitor can filter out possible interference on the transmission line.

[0046] When the controller detects that the load current within the power distribution unit (including the linear array focal plane group, area array focal plane group, and imaging processor group) exceeds 10% to 20% of the rated current, the power distribution unit automatically implements current limiting protection and shuts off the output voltage. When the controller detects an abnormal telemetry voltage within the power distribution unit, it shuts off power to the abnormal telemetry voltage group within the power distribution unit (including the linear array focal plane group, area array focal plane group, and imaging processor group). When the controller detects that the operating temperature of the linear array focal plane group, area array focal plane group, and imaging processor group exceeds the safe temperature threshold, it shuts off power to the abnormal temperature group within the power distribution unit. By monitoring the load current, telemetry voltage, and operating temperature of each device in the power distribution unit, the controller can quickly shut down the abnormal device to prevent it from affecting other normally operating devices. If a laser group experiences an abnormality, the controller automatically implements current limiting protection and shuts off the output voltage.

[0047] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved. This is not limited herein.

[0048] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. An imaging system with high electromagnetic compatibility performance, characterized in that: It includes a distributor, a linear array focal plane group, an area array focal plane group, an imaging processor group, a laser group and a controller; wherein, The distributor receives primary power input from the outside and provides independent secondary power supply for the linear array focal plane group, area array focal plane group, imaging processor group and controller; the controller communicates with the linear array focal plane group, area array focal plane group, laser group and imaging processor group respectively, and receives telemetry signals returned by the linear array focal plane group, area array focal plane group, laser group and imaging processor group; the controller controls the distributor to control the power on and off of the linear array focal plane group, area array focal plane group and imaging processor group; The casing of the power distributor, the casing of the linear array focal plane group, the casing of the area array focal plane group, the casing of the imaging processor group, the casing of the laser group, and the casing of the controller are all connected to the shielded ground of their corresponding cables. At the same time, the casing of the power distributor, the casing of the linear array focal plane group, the casing of the area array focal plane group, the casing of the imaging processor group, the casing of the laser group, and the casing of the controller are all connected to the cabin panel; the secondary ground inside the power distributor and the secondary ground inside the laser group are not connected to their own casings; the secondary ground inside the linear array focal plane group, the secondary ground inside the area array focal plane group, the secondary ground inside the imaging processor group, and the secondary ground inside the controller are all crimped to their own casings through copper grounding.

2. The imaging system with high electromagnetic compatibility according to claim 1, characterized in that: An isolation transformer is used inside the distributor to isolate the external input primary power supply from the output secondary power supply, and independently provide secondary power supply for the linear array focal plane group, area array focal plane group, imaging processor group and controller. The power supply of the linear array focal plane group, the power supply of the area array focal plane group, the power supply of the imaging processor group and the power supply of the controller are not connected inside the distributor, and the secondary return line of the linear array focal plane group, the secondary return line of the area array focal plane group, the secondary return line of the imaging processor group, the secondary return line of the laser group and the secondary return line of the controller are not connected inside the distributor.

3. The imaging system with high electromagnetic compatibility according to claim 1, characterized in that: The telemetry signals returned to the controller by the linear array focal plane group, the area array focal plane group, the laser group and the imaging processor group are transmitted using a photoelectric isolation device.

4. The imaging system with high electromagnetic compatibility according to claim 3, characterized in that: The optoelectronic isolation equipment includes matching optoelectronic transmitting equipment and optoelectronic receiving equipment. The linear array focal plane group, area array focal plane group, laser group and imaging processor group respectively send their own telemetry signals through independent optoelectronic transmitting equipment, and the controller receives each telemetry signal through the optoelectronic receiving equipment corresponding to each optoelectronic transmitting equipment.

5. The imaging system with high electromagnetic compatibility according to claim 3, characterized in that: The secondary ground inside the laser group is not connected to the secondary ground inside the controller.

6. The imaging system with high electromagnetic compatibility according to claim 4, characterized in that: The controller includes a control logic circuit and a focus motor; wherein, One connection method between the control logic circuit and the focus motor is as follows: the signal of the control logic circuit and the signal of the focus motor are transmitted using a photoelectric isolation device, and the secondary ground inside the control logic circuit and the secondary ground inside the focus motor are not connected; Another way to connect the control logic circuit and the focusing motor is: the signal of the control logic circuit is connected to the signal of the focusing motor for transmission, the secondary ground inside the control logic circuit is connected to the secondary ground inside the focusing motor, and focusing and imaging work in a time-sharing manner.

7. The imaging system with high electromagnetic compatibility according to claim 2, characterized in that: The secondary return line in the distributor that supplies power to the linear array focal plane group, the area array focal plane group, and the imaging processor group is connected to the secondary ground inside the controller through a series resistor.

8. The imaging system with high electromagnetic compatibility according to claim 7, characterized in that: The resistance of the series resistor Select by: ； Where R is the resistance of the secondary circuit in the distributor. is the noise voltage threshold for stable signal transmission, is the inductive reactance of the transmission line, and I is the maximum current value in the secondary return current of the linear array focal plane group, area array focal plane group, imaging processor group, laser group and controller.

9. The imaging system with high electromagnetic compatibility according to claim 1, characterized in that: The key signals output by the controller are driven by the OC gate drive circuit. The key signals are connected to their respective secondary power supplies using pull-up resistors at the linear array focal plane group, area array focal plane group, and imaging processor group ends. At the same time, the key signals are connected to their respective internal secondary grounds using grounding capacitors at the linear array focal plane group, area array focal plane group, and imaging processor group ends.

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