A telemetry monitoring system for occultation detection payload

Abstract

The present application provides a telemetry monitoring system for an occultation detection payload, including multiple telemetry monitoring links, each of which includes a connected DCDC conversion module and a telemetry monitoring module, the DCDC conversion module is connected to a primary power supply input at the front end, and the telemetry monitoring module is connected to a rear end load module; the telemetry monitoring module is composed of a low voltage difference regulator and a telemetry circuit connected to the low voltage difference regulator, wherein the low voltage difference regulator is configured to perform secondary conversion on the high ripple voltage output by the DCDC conversion module to provide a stable working voltage to the load module; the telemetry circuit is configured to determine telemetry voltage data based on the collected front-stage input voltage and rear-stage output voltage of the low voltage difference regulator, and monitor the status of each load module inside the payload according to the telemetry voltage data. The present application can greatly reduce the monitoring pressure of the host computer interface, and effectively improve the monitoring efficiency of the detection system and the reliability of the detection payload.

Description

Technical Field

[0001] The present application belongs to the technical field of occultation detection payloads, and in particular, relates to a telemetry monitoring system for occultation detection payloads. Background Art

[0002] Occultation detection technology is an effective detection technology that uses the global satellite navigation system (GNSS) to detect environmental parameters of the atmosphere and ionosphere. With the rapid development of commercial aerospace in recent years, this detection technology has been continuously improved, and the detection accuracy and detection speed have been greatly improved. The basic principle of the payload is to receive GNSS navigation star signals that pass through the atmosphere and ionosphere. During the propagation process, the important parameters of the signal itself, such as frequency, phase, amplitude, etc., will undergo relevant changes. These changes will carry information about the temperature and humidity of the atmosphere along the path the signal passes through, and the electron density of the ionosphere. The payload uses the internal occultation-related algorithm to perform inversion and solution, and can obtain important detection information such as the real-time temperature, humidity, air pressure of the atmosphere, and the electron density of the ionosphere. This plays an irreplaceable role in enhancing the positioning accuracy of the navigation system, monitoring the space environment, and improving the accuracy of weather forecasts.

[0003] At present, for the sake of high reliability, occultation detection payloads are required to monitor the working status of their main working units in real time inside the payload. The monitored object is generally the telemetry data of the power supply voltage of each working unit. Under normal circumstances, a normal telemetry voltage indicates that the corresponding working unit is in normal working condition. On the contrary, when the telemetry voltage of a certain working unit becomes abnormal due to force majeure factors such as internal or external factors of the payload, it indicates that the working unit must be in an abnormal state. At this time, the system control unit that receives the telemetry information needs to promptly cut off the power supply unit of the corresponding working unit and shut down the abnormal module to ensure that other working units are not affected by the abnormal module, thereby ensuring the safety of the overall payload and the entire satellite platform.

[0004] In particular, due to the complex internal system design of the detection payload and the large number of functional modules, for safety reasons, it is often required to monitor the telemetry data of each level of conversion voltage so that when an abnormality occurs, it can be quickly and accurately located; however, this often leads to greater pressure on the monitoring host computer interface and the inability to display other important information that needs to be displayed, such as algorithm execution status, internal temperature conditions and a large amount of other key information that needs to be displayed by the host computer, resulting in poor reliability and safety of the occultation detection payload. Summary of the invention

[0005] In view of this, the present application aims to propose a telemetry monitoring system for occultation detection payload to solve at least one of the above problems.

[0006] To achieve the above purpose, the technical solution of this application is implemented as follows:

[0007] The present application provides a telemetry monitoring system for an occultation detection payload, comprising a plurality of telemetry monitoring links, each of which comprises a connected DCDC conversion module and a telemetry monitoring module, wherein the DCDC conversion module is connected to a primary power supply inputted at the front end, and the telemetry monitoring module is connected to a rear end load module;

[0008] The telemetry monitoring module is composed of a low voltage dropout regulator and a telemetry circuit connected to the low voltage dropout regulator, wherein the low voltage dropout regulator is configured to perform secondary conversion on the high ripple voltage output by the DCDC conversion module to provide a stable operating voltage to the load module; the telemetry circuit is configured to determine telemetry voltage data based on the collected front-stage input voltage and rear-stage output voltage of the low voltage dropout regulator, and monitor the status of each load module inside the load according to the telemetry voltage data.

[0009] Further, the low voltage difference regulator includes a voltage stabilizing chip, the input end of the voltage stabilizing chip is connected to the output end of the DCDC conversion module through a first resistor and a second resistor connected in parallel, and the output end of the voltage stabilizing chip is connected to the load module through a third resistor and a fourth resistor connected in parallel, wherein the load module at least includes an ARM processing module, an FPGA module and a data interface module;

[0010] The input end of the voltage stabilizing chip is also grounded through a fifth resistor and a seventh resistor connected in series, wherein the point between the fifth resistor and the seventh resistor is configured as a remote sensing voltage output point, and the output point is connected to the output end of the voltage stabilizing chip through an eighth resistor and a ninth resistor connected in series;

[0011] The input end and the output end of the voltage stabilizing chip are also respectively connected with voltage stabilizing capacitor groups connected in parallel.

[0012] Furthermore, the output ends of multiple telemetry circuits are all connected to the ARM processing module, and the ARM processing module is configured to read the telemetry voltage data of the telemetry voltage output point of each link according to a preset monitoring strategy, and take an average value of the read telemetry voltage data, compare the average value with a pre-stored set range, and control the action of the voltage stabilizing chip according to the comparison result.

[0013] Furthermore, the pre-stored setting range is 2.454±0.3.

[0014] Furthermore, the telemetry voltage output point is also grounded via a sixth capacitor, and the sixth capacitor and the seventh resistor form a low-pass filter circuit.

[0015] Furthermore, the enable pin of the voltage stabilizing chip is connected to a tenth resistor, and the other end of the tenth resistor is connected to the input end of the voltage stabilizing chip.

[0016] Furthermore, the resistance values ​​of the first resistor, the second resistor, the third resistor and the fourth resistor are all 0Ω.

[0017] Furthermore, the voltage stabilizing chip adopts a chip of model XC6209E332MR.

[0018] Compared with the prior art, the telemetry monitoring system for occultation detection payload described in this application has the following beneficial effects:

[0019] The telemetry monitoring system for an occultation detection payload described in the present application designs a telemetry circuit, which can simultaneously monitor the working status of the front and rear stages of the low-voltage difference regulator based on one telemetry quantity, thereby greatly reducing the monitoring pressure of the host computer interface and effectively reducing the complexity of the monitoring strategy, thereby effectively improving the monitoring efficiency of the detection system and the reliability of the detection payload. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 This is an overall structural block diagram of a telemetry monitoring system for occultation detection payload described in an embodiment of the present application;

[0022] Figure 2 A schematic diagram of each load unit of the occultation payload described in an embodiment of the present application;

[0023] Figure 3 This is a schematic diagram of the telemetry circuit connection described in an embodiment of the present application. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0025] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] The occultation detection payload is a satellite-borne meteorological detection payload. Its basic principle is to receive signals emitted by the global navigation system through detection payloads distributed in low orbits. When these signals pass through the atmosphere and ionosphere, their own parameters such as frequency, phase or amplitude will change accordingly. These parameters contain relevant information about the paths through which the signals pass through the atmosphere and ionosphere. The occultation detection payload can solve this information in real time through internal correlation algorithms. This information plays an important role in improving the accuracy of weather forecasts and the positioning accuracy of navigation systems. For reliability reasons, the detection payload needs to monitor the status of the main working unit modules in real time, which is reflected in the collection and processing of the working telemetry voltage of each module.

[0027] Under normal circumstances, as long as the working voltage of each module is normal and stable, the payload system as a whole will be in a stable state; on the contrary, when the telemetry value of the working voltage of a module is abnormal due to internal or external force majeure of the payload, the working unit must be in an abnormal working state. At this time, the control module needs to take corresponding actions quickly to shut down the abnormal unit to ensure that other modules of the payload are not affected by the abnormal module, thereby ensuring the safety of the detection payload and the entire satellite platform. This involves the design of the telemetry circuit inside the occultation payload and the implementation of specific monitoring strategies.

[0028] In view of this practical problem, the present application proposes a telemetry monitoring system for occultation detection payload, including multiple telemetry monitoring links, each of which includes a DCDC conversion module and a telemetry monitoring module connected to each other, the DCDC conversion module is connected to a primary power supply input at the front end, and the telemetry monitoring module is connected to a rear end load module;

[0029] The telemetry monitoring module consists of a low voltage dropout regulator and a telemetry circuit connected to the low voltage dropout regulator, wherein the low voltage dropout regulator is configured to perform secondary conversion on the high ripple voltage output by the DCDC conversion module to provide a stable operating voltage to the load module; the telemetry circuit is configured to determine telemetry voltage data based on the collected front-stage input voltage and rear-stage output voltage of the low voltage dropout regulator, and monitor the status of each load module inside the load according to the telemetry voltage data.

[0030] The telemetry monitoring system for an occultation detection payload described in the present application monitors the front-stage input voltage and the rear-stage output voltage of an LDO (Low Dropout Regulator, a low voltage difference regulator selected in this embodiment is an XC6209E332MR voltage regulator chip) simultaneously through a telemetry monitoring system. When an abnormality occurs, the abnormality location can be accurately located and corresponding processing can be performed, thereby effectively improving the reliability and safety of the payload.

[0031] Specifically, in this embodiment, the division of each functional module and the power supply strategy inside the load are first described in detail, and then a reasonable and effective monitoring strategy is designed for the telemetry of the working status of each working unit inside the load; and the following specific implementation plan is given for the reasonable range setting of the telemetry data.

[0032] Figure 1 The overall structural block diagram of the internal telemetry monitoring system of the occultation payload is as follows: the main functional modules of the occultation payload can be divided into three parts, namely, ARM and related peripheral modules (i.e., ARM processing module), FPGA and related peripheral modules (i.e., FPGA module), and interface module and related peripheral parts (i.e., data interface module); after the external primary power is input into the payload, it is given to the DCDC conversion module through the fuse and surge suppression module. According to the composition of the main functional modules of the occultation payload, the DCDC conversion module is divided into three routes for power conversion respectively. According to the specific load and the back-end load, the number and model of the DCDC conversion module and the current output capacity will also be adjusted accordingly, which is not specifically limited here.

[0033] The DCDC conversion module itself is a switching power supply. Its basic principle is to use the charging and discharging principle of inductors and capacitors and control their charging and discharging with MOS switches to complete the conversion of the required output voltage. At present, the conversion efficiency of the DCDC conversion module of conventional satellite payloads can reach more than 90%; however, due to the switching characteristics of the DCDC conversion module itself, the output voltage ripple will be large, but the large ripple will cause the back-end processor to malfunction. Therefore, the first-level voltage output cannot be directly given to the back-end microprocessor and other load units;

[0034] In order to meet the low ripple requirements of the back-end load, a corresponding LDO unit needs to be added between the DCDC conversion module and the load to perform secondary conversion on the high ripple voltage output by the DCDC conversion module. Since the working mechanism of the LDO itself is to use an operational amplifier with a MOS tube, and use the voltage control current output principle of the MOS tube to output a stable voltage value through resistor voltage regulation, the output ripple is extremely small, which can better meet the high steady-state voltage requirements of the load; and after the conversion of the first-stage DCDC conversion module, it also avoids directly converting the primary power supply through the LDO, which makes the voltage difference between the front and rear ends of the LDO too large, resulting in excessive losses, making the overall power module efficiency low, and causing serious heating problems.

[0035] In particular, Figure 1 The three main functional modules within the mid-occultation payload can be further subdivided according to the specific detection tasks performed, such as Figure 2 The following is a block diagram showing the further subdivision of the three main functional modules within the payload, as follows:

[0036] ARM and related peripheral modules can be divided into baseband algorithm processing ARM module and control and interface ARM module. The baseband algorithm processing ARM is mainly responsible for controlling the data loop and acquiring the occultation data observation quantity; the control and interface ARM is mainly responsible for receiving platform-related instructions, sending the acquired occultation detection data to the outside and selecting the specific interface type.

[0037] FPGA and related peripheral modules will also vary depending on the navigation star to be observed. Since different navigation stars correspond to different parameters such as frequency points, different FPGAs need to be configured to receive and process specific navigation star signals, and the corresponding observation data is processed and sent to the ARM unit. The block diagram only lists two FPGAs corresponding to two navigation stars, but in fact the number of FPGAs can be increased or decreased according to the specific application situation.

[0038] The interface module and related peripherals can be divided into detection data transmission interface module and remote control telemetry data interface module according to the specific execution functions; the detection data transmission interface module includes various types of data interfaces, whose function is to send the detection data solved by the payload to the whole satellite platform through a specific interface, and the commonly used interfaces are LVDS interface, GMII interface and 2711 interface, etc. These interfaces may not be integrated into the payload at the same time, and there may be more than the number listed in the diagram, but it does not affect its basic functional division. The function of the remote control telemetry data interface is to receive the remote control instructions of the whole satellite platform and send the telemetry data to the whole satellite platform so that the whole satellite platform can monitor the payload status in real time. The commonly used interfaces are CAN interface, RS422 interface, RS485 interface and UART interface. Similarly, these interfaces may be integrated at the same time in the actual payload, and there may be more than the interfaces listed in the diagram, but it does not affect its basic functional division.

[0039] Combination Figure 2 The specific division shown can select specific models and specific numbers of LDOs to meet specific load requirements. The main measurement indicators are the output voltage level, output current capability, and whether there are timing control requirements for the LDO. Similarly, in order to match the output of the corresponding LDO, the front-stage DCDC conversion module also needs to be adjusted accordingly according to actual needs, but it does not affect its basic functional division; for example, the interface module in the figure contains multiple interface types, and each interface type includes different interface chips and drive circuits. For these different interface chip voltage and current requirements, the corresponding type of LDO can be selected for power supply, and then respectively supplied to the corresponding load modules at the back end; the power supply strategy of the ARM processing module and the FPGA module is consistent with the interface module.

[0040] The LDO front and rear stages are connected through a resistor network to form a telemetry circuit, which can realize simultaneous monitoring of the input voltage and output voltage. The problem can be quickly located according to the different monitoring data, avoiding the problem of excessive telemetry and complicated monitoring strategy caused by adding telemetry circuits at the input and output ends respectively. It can effectively simplify the monitoring strategy and improve the monitoring efficiency.

[0041] Figure 2The following is a detailed connection diagram of the telemetry circuit of the occultation payload. VCC_MCU_IN is the input voltage output by the DCDC conversion module to the LDO. Two 0Ω resistors need to be added at the input and output positions to facilitate the debugging and confirmation of the voltage of the LDO front and rear stages. After the resistors R5 and R7 are connected in series, one end is connected to the voltage input end and the other end is grounded. The middle position of the resistors R5 and R7 is the telemetry data output point. This position is connected to the LDO output end after being connected in series with the resistors R8 and R9. The resistors R8 and R9 adopt a series structure to improve the reliability of the telemetry circuit. In this way, the output end and the input end are connected together through the resistor network, so that the telemetry point voltage between the resistors R5 and R7 is determined by the input voltage and the output voltage. The telemetry point voltage is VCC_MCU_YC, and the telemetry voltage data is directly given to the ADC sampling unit of the ARM processing module for reading.

[0042] The monitoring strategy of the ARM processing module is: to read the telemetry voltage data 5 times per second, take the average value after reading, and then compare it with the pre-stored set value; when the telemetry value is not within the reasonable range of the set value, the ARM processing module will pull down the enable pin of the LDO of the corresponding unit, that is, Figure 3 The LDO_OFF signal in the module ensures that the module is powered off and protects other functional modules from being affected by abnormal modules.

[0043] In addition, the capacitance of resistor C6 in the circuit is 0.1uF, which forms a low-pass RC filter circuit with resistor R7, which can stabilize the telemetry voltage output to ensure output stability; capacitors C1, C2, and C3 are input stabilizing capacitors at the front end of the LDO, and capacitors C4 and C5 are output stabilizing capacitors at the back end of the LDO; R10 is the pull-up resistor of the LDO enable pin, which ensures that the LDO is in the on state in the initial state.

[0044] The relationship between the module telemetry voltage and the input voltage and output voltage is described as follows: Assume that the telemetry point voltage value is V1, the LDO input terminal input voltage is Vin, and the LDO output terminal output voltage is Vout. Figure 3 As shown, V1 is determined by the input voltage Vin and the output voltage Vout. By obtaining the expression of V1 and combining it with the specific application circuit, the input and output states can be monitored simultaneously.

[0045] According to Kirchhoff's current law, the current in the resistor R7 loop is composed of the input voltage through the resistor R5, the current from the resistor R7 to the ground, and the current in the output voltage through the resistor R8 and the resistor R9 loop. The product of the current and the resistor R7 is equal to V1.

[0046] That is: [(Vin-V1) / R7+(Vout-V1) / (R8+R9)]*R7=V1;

[0047] According to the above formula, we can get the unique correspondence between V1 and LDO input voltage and output voltage, V1=R7[R7*Vin+(R8+R9)*Vout] / [1+R7(R7+R8+R9)].

[0048] For example, when the input voltage is 4V, the output voltage is 3.3V, the voltage divider resistors R5 and R7 are 1K respectively, and the resistors R8 and R9 connecting the output and input are 470Ω respectively; then according to the above expression, there are the following three cases:

[0049] When both the input and output are normal, according to Kirchhoff's current law, the voltage monitoring value at this time can be obtained as 2.454V;

[0050] When the LDO back-end load is abnormal due to internal or external force majeure factors, causing the LDO back-end output to be short-circuited, then due to the foldback short-circuit protection function of the LDO itself, the output voltage will be pulled down to 0V, while the input voltage remains unchanged. Then, according to the circuit connection diagram and expression, it can be concluded that the voltage monitoring data at this time is 1.307V;

[0051] When the front-end DCDC output is abnormal, the LDO front-end and back-end voltages will be abnormal, then the monitoring voltage data must be less than 1.307V;

[0052] The above three situations include all possible situations of telemetry data. According to the specific telemetry data, the status of each working unit inside the load can be reasonably monitored, and the fault point can be quickly located when an abnormality occurs.

[0053] In particular, attention should be paid to the setting of the reasonable range of telemetry voltage: the reasonable range cannot be set too wide, otherwise it cannot play a monitoring role, and it cannot respond quickly when an abnormality occurs, and the reliability of the payload cannot be guaranteed; the reasonable range cannot be set too narrow, because the operating environment of the payload is in the space environment, and the actual temperature difference during on-orbit operation is very large, and temperature changes will cause changes in current and then cause changes in telemetry voltage. Setting it too narrow can easily lead to false triggering, affecting the normal execution of the payload detection task.

[0054] Therefore, the telemetry voltage setting requires that the load complete the corresponding high and low temperature experiments on the ground, and take the maximum and minimum values ​​as the minimum range (the reasonable range set in this embodiment is 2.454±0.3), leaving an appropriate margin to deal with the telemetry voltage drift caused by device aging, short-term latching of semiconductor devices, etc.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0056] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A telemetry monitoring system for occultation detection payload, characterized in that: It includes multiple telemetry monitoring links, each of which includes a DCDC conversion module and a telemetry monitoring module connected to each other, the DCDC conversion module is connected to a primary power supply input from the front end, and the telemetry monitoring module is connected to a rear end load module; The telemetry monitoring module is composed of a low voltage dropout regulator and a telemetry circuit connected to the low voltage dropout regulator, wherein the low voltage dropout regulator is configured to perform secondary conversion on the high ripple voltage output by the DCDC conversion module to provide a stable operating voltage to the load module; the telemetry circuit is configured to determine telemetry voltage data based on the collected front-stage input voltage and rear-stage output voltage of the low voltage dropout regulator, and monitor the status of each load module inside the load according to the telemetry voltage data; The low voltage difference regulator includes a voltage stabilizing chip, the input end of the voltage stabilizing chip is connected to the output end of the DCDC conversion module through a first resistor and a second resistor connected in parallel, and the output end of the voltage stabilizing chip is connected to the load module through a third resistor and a fourth resistor connected in parallel, wherein the load module at least includes an ARM processing module, an FPGA module and a data interface module; The input end of the voltage stabilizing chip is also grounded through a fifth resistor and a seventh resistor connected in series, wherein the point between the fifth resistor and the seventh resistor is configured as a remote sensing voltage output point, and the output point is connected to the output end of the voltage stabilizing chip through an eighth resistor and a ninth resistor connected in series; The input end and the output end of the voltage stabilizing chip are also respectively connected with voltage stabilizing capacitor groups connected in parallel.

2. The telemetry monitoring system for occultation detection payload according to claim 1, characterized in that: The output ends of multiple telemetry circuits are all connected to the ARM processing module, and the ARM processing module is configured to read the telemetry voltage data of the telemetry voltage output point of each link according to a preset monitoring strategy, and take an average value of the read telemetry voltage data, compare the average value with a pre-stored set range, and control the action of the voltage stabilizing chip according to the comparison result.

3. The telemetry monitoring system for occultation detection payload according to claim 2, characterized in that: The pre-stored setting range is 2.454±0.

3.

4. The telemetry monitoring system for occultation detection payload according to claim 1, characterized in that: The telemetry voltage output point is also grounded via a sixth capacitor, and the sixth capacitor and the seventh resistor form a low-pass filter circuit.

5. The telemetry monitoring system for occultation detection payload according to claim 1, characterized in that: The enable pin of the voltage stabilizing chip is connected to a tenth resistor, and the other end of the tenth resistor is connected to the input end of the voltage stabilizing chip.

6. The telemetry monitoring system for occultation detection payload according to claim 1, characterized in that: The resistance values ​​of the first resistor, the second resistor, the third resistor and the fourth resistor are all 0Ω.

7. The telemetry monitoring system for occultation detection payload according to claim 1, characterized in that: The voltage stabilizing chip adopts the XC6209E332MR chip.

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