Direct-connection polar orbit meteorological satellite handheld terminal and direct-connection polar orbit meteorological satellite method thereof

Abstract

The invention provides a direct-connection polar orbit meteorological satellite handheld terminal and a direct-connection polar orbit meteorological satellite method thereof. Comprising the following steps: acquiring a satellite uplink signal and a satellite downlink signal, processing the satellite uplink signal and the satellite downlink signal through a duplexer, transmitting the processed signal to a high-speed agile transceiver for frequency conversion and conversion, interacting with a multifunctional system on chip to complete satellite transit window calculation and parameter adjustment, and displaying the satellite transit window calculation and parameter adjustment to a user through a display screen. Meteorological satellite orbit parameters are pre-stored in a lightweight form; calculating a transit time window of the polar orbit meteorological satellite according to the orbit parameters of the meteorological satellite; estimating the signal frequency offset of the polar orbit meteorological satellite, and performing frequency offset compensation; frequency offset compensation is completed, access information is sent, and polar orbit meteorological satellite signals are captured; requesting polar orbit meteorological satellite data according to the carrier offset; and receiving polar orbit meteorological satellite data, wherein the polar orbit meteorological satellite data comprises message information issued by a polar orbit meteorological satellite and orbit parameters. According to the method, the complexity of a program is greatly simplified, and implementation on a small-computing-power embedded platform is facilitated.

Description

Technical Field

[0001] The present invention relates to the field of satellite mobile communication technology, and in particular to a handheld terminal directly connected to a polar-orbiting meteorological satellite and a method for directly connecting to a polar-orbiting meteorological satellite. Background Art

[0002] Meteorological satellites are the most widely used and most efficient satellites among my country's civilian remote sensing satellites. Their main application areas include weather forecasting, climate change research, disaster prevention and mitigation, ecological and environmental monitoring, water conservancy, forestry, grassland, aviation and transportation. With the development of meteorological satellite technology, meteorological satellites have changed from traditional observation data to direct product provision. my country's new generation of polar-orbiting meteorological satellites have the ability to directly provide products. Satellites are equipped with onboard broadcasting equipment, which can directly release typhoon and forest fire information to subscribers during the satellite's transit, which is used to guide real-time emergency response on the ground.

[0003] In the field of disaster prevention and mitigation, terminals that receive direct broadcast information from meteorological satellites need to have the characteristics of low power consumption, light weight, and high reliability. Traditional terminals use a secondary frequency conversion system, which includes complex radio frequency channels for receiving, amplifying, and frequency conversion, and large-scale FPGA, DSP and other digital processors. They are large in size and have high power consumption requirements, making it difficult to support portable applications in the field. The existing technology uses orbital recursion to achieve this, which is complex to implement. The existing technology uses the method of calculating the satellite position and speed to obtain the radial velocity to calculate the Doppler frequency. The calculation is complex and difficult to implement on a small computing power embedded platform. In addition, the existing technology mostly uses secondary frequency conversion and large-scale FPGA, DSP and other digital devices to achieve this, which results in large hardware scale and high power consumption requirements. Summary of the invention

[0004] In view of the defects in the prior art, an object of the present invention is to provide a handheld terminal directly connected to a polar-orbiting meteorological satellite and a method for directly connecting to a polar-orbiting meteorological satellite.

[0005] A handheld terminal directly connected to a polar-orbiting meteorological satellite provided by the present invention comprises: a multifunctional system-on-chip, a high-speed agile transceiver, and a display screen;

[0006] The satellite uplink signal and downlink signal are obtained and processed by the duplexer, then transmitted to the high-speed agile transceiver for frequency conversion and conversion processing, and then interact with the multi-functional system-on-chip to complete the satellite transit window calculation and parameter adjustment, and are displayed to the user through the display screen.

[0007] Preferably, the multifunctional system-on-chip is responsible for the control of the entire terminal, completing satellite transit window calculation, parameter adjustment, request and reception of satellite products, Bluetooth and storage management.

[0008] Preferably, the high-speed agile transceiver completes down-conversion and analog-to-digital conversion of satellite downlink signals and up-conversion and digital-to-analog conversion of terminal uplink signals;

[0009] The display screen displays the products sent by the satellite and the status of the handheld terminal itself.

[0010] Preferably, it also includes: a duplexer, a receiving channel, a transmitting channel, a memory, a button and a Bluetooth module;

[0011] The duplexer completes the composite antenna transmission of the satellite downlink signal and the handheld terminal uplink signal;

[0012] The receiving channel completes filtering and amplification of satellite downlink signals;

[0013] The sending channel completes filtering and amplification of the terminal uplink signal;

[0014] The memory completes the storage of satellite orbit parameters and issued products;

[0015] The button is used to set the mode of the handheld terminal;

[0016] The Bluetooth module is used for communication with third-party devices.

[0017] Preferably, it also includes: a lithium battery, a charge and discharge management module and a composite interface;

[0018] The lithium battery and the charge and discharge management module are used for charge management, discharge management and level conversion;

[0019] The composite interface is used for inputting power, interacting with external data signals, and charging third-party devices.

[0020] According to a method for directly connecting to a polar-orbiting meteorological satellite provided by the present invention, the method for directly connecting to a polar-orbiting meteorological satellite using the handheld terminal for directly connecting to a polar-orbiting meteorological satellite includes:

[0021] Step S1: pre-storing meteorological satellite orbit parameters in a lightweight form;

[0022] Step S2: Calculating the time window of the polar-orbiting meteorological satellite transit according to the meteorological satellite orbit parameters;

[0023] Step S3: estimating the frequency deviation of the polar-orbiting meteorological satellite signal and performing frequency deviation compensation;

[0024] Step S4: completing frequency offset compensation, sending access information, and capturing polar-orbiting meteorological satellite signals;

[0025] Step S5: Requesting polar-orbiting meteorological satellite data according to the carrier offset;

[0026] Step S6: receiving the polar-orbiting meteorological satellite data, wherein the polar-orbiting meteorological satellite data includes message information and orbital parameters sent by the polar-orbiting meteorological satellite.

[0027] Preferably, step S2 comprises:

[0028] Step S2.1: Use Beidou / GPS device to obtain the longitude λ1 and latitude of the current location and the current time t1;

[0029] Step S2.2: Estimate satellite arrival latitude The time series t m , the calculation formula is as follows:

[0030]

[0031] In the formula, represents the latitude of the satellite's subsatellite point at time t0, and m represents the arrival latitude The serial number of T represents the orbital period of the meteorological satellite to be connected stored in advance;

[0032] Step S2.3: Estimate the m The longitude of the satellite subsatellite point at this time m , the calculation formula is as follows:

[0033] λ m =λ0-2π(t m -t0) / 24h

[0034] Where λ0 represents the longitude of the satellite's sub-satellite point at time t0;

[0035] Step S2.4: Estimate the m The distance d between the satellite and the current location at this moment m , the calculation formula is as follows:

[0036]

[0037] Where R represents the radius of the earth;

[0038] Step S2.5: Estimate the m The angle θ between the satellite and the current location at this moment m , the calculation formula is as follows:

[0039]

[0040] Step S2.6: When θ m Greater than the preset threshold θ t When , it means the satellite is visible to the location, otherwise it is invisible.

[0041] Preferably, the step S3 comprises:

[0042] Step S3.1: Estimate the maximum Doppler frequency shift Δf m , the calculation formula is as follows:

[0043]

[0044] In the formula, f0 represents the carrier frequency, g represents the gravitational acceleration, θ m Indicates t m The angle between the satellite and the current location at the moment, R represents the radius of the earth, c represents the speed of light, and h represents the orbital height of the satellite;

[0045] Step S3.2: Estimate the transit time t, calculated as follows:

[0046]

[0047] Preferably, step S4 comprises:

[0048] Step S4.1: In the local signal carrier, set the frequency offset to Δf when the satellite enters m , set the frequency deviation to -Δf when the satellite leaves the country m , and for Δf m ~-Δf m Perform linear interpolation to generate a frequency deviation-timetable;

[0049] Step S4.2: adjusting the frequency signal of the access satellite to send an access request instruction according to the frequency deviation-timetable;

[0050] Step S4.3: According to the frequency deviation-timetable, adjusting the local carrier signal of the receiving satellite to capture the satellite downlink return command;

[0051] Step S4.4: confirm that the reply format meets the requirements, and adjust the uplink frequency signal according to step S4.2 to send a confirmation instruction;

[0052] Step S4.5: adjusting the local carrier signal according to step S4.3 to complete the capture of the downlink signal;

[0053] Step S4.6: Use the local tracking loop to track the satellite carrier signal and generate a carrier offset.

[0054] Preferably, step S5 comprises:

[0055] Step S5.1: Generate a carrier offset according to the satellite carrier signal tracked by the local tracking loop, adjust the uplink frequency signal, and send a regional product request instruction;

[0056] Step S5.2: The satellite receives the product request instruction and sends the corresponding product;

[0057] Step S5.3: Complete the product reception and push it to the mobile phone via Bluetooth.

[0058] Compared with the prior art, the present invention has the following beneficial effects:

[0059] 1. The method of directly connecting the polar-orbiting meteorological satellite of the present invention utilizes the characteristics that the polar-orbiting meteorological satellite is a circular orbit, and the ascending node or descending node time is almost unchanged to calculate the satellite transit time, which greatly simplifies the complexity of the program;

[0060] 2. The present invention estimates the Doppler frequency deviation of the signal according to the highest elevation angle during the transit period, which is convenient for implementation on a small computing power embedded platform;

[0061] 3. The present invention adopts a highly integrated high-speed agile transceiver to realize direct up-conversion / down-conversion, and adopts a multifunctional on-chip system to realize complex system management, despreading, demodulation, decoding, as well as encoding, spread spectrum, and modulation operations. It has the advantages of simple software and hardware systems and low power consumption. The existing technology mostly adopts secondary frequency conversion and large-scale FPGA, DSP and other digital devices to achieve it, and the hardware scale is huge and the power consumption requirement is large. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0063] Figure 1 It is a schematic diagram of the composition of the handheld terminal directly connected to the polar-orbiting meteorological satellite of the present invention;

[0064] Figure 2 It is a schematic diagram of the process of directly connecting the terminal of the present invention to a polar-orbiting meteorological satellite. DETAILED DESCRIPTION

[0065] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0066] The present invention realizes lightweight interaction between ground and polar-orbiting meteorological satellites, has the advantages of simple principle, compact composition, easy operation, high reliability, good stability, etc., and can be used in the fields of emergency rescue, disaster prevention and mitigation.

[0067] Embodiment 1

[0068] According to the present invention, a handheld terminal directly connected to a polar-orbiting meteorological satellite is provided. Figure 1As shown, it includes: a multifunctional system-on-chip, a high-speed agile transceiver, a duplexer, a receiving channel, a transmitting channel, a memory, a display screen, a button, a Bluetooth module, a lithium battery, a charge and discharge management module and a composite interface.

[0069] The satellite uplink signal and downlink signal are obtained and processed by the duplexer, then transmitted to the high-speed agile transceiver for frequency conversion and conversion, and then interact with the multi-functional system-on-chip to complete the satellite transit window calculation and parameter adjustment, and are presented to the user through the display.

[0070] The multifunctional system-on-chip is responsible for the control of the entire terminal, completing satellite transit window calculation, parameter adjustment, satellite product request and reception, Bluetooth and storage management; the high-speed agile transceiver completes the down-conversion, analog-to-digital conversion of the satellite downlink signal and the up-conversion and digital-to-analog conversion of the terminal uplink signal; the duplexer completes the composite antenna transmission of the satellite downlink signal and the handheld terminal uplink signal; the receiving channel completes the filtering and amplification of the satellite downlink signal; the transmitting channel completes the filtering and amplification of the terminal uplink signal; the memory completes the storage of satellite orbit parameters and issued products; the display screen completes the display of the satellite issued products and the handheld terminal's own status display; the button is used to set the mode of the handheld terminal; the Bluetooth module is used for communication with third-party devices; the lithium battery and charge and discharge management module are used for charging management, discharge management and level conversion; the composite interface is used for power input, interaction of external data signals and charging of third-party devices.

[0071] In actual implementation, the high-speed agile transceiver can choose the domestic GM4634 or the imported AD9364 device, whose operating frequency band is 70MHz to 6GHz, which can meet the requirements of polar-orbiting meteorological satellite signal transmission and reception. The multi-function system-on-chip can choose the imported ZU9EG device, which includes PS and PL parts. The terminal management function can be implemented in the PS part, and the signal processing part can be implemented by the PL part.

[0072] Embodiment 2

[0073] like Figure 2 As shown in the figure, the handheld terminal has steps such as request and confirmation in the access process. Since the satellite is in high-speed motion, the received and transmitted signals have Doppler frequency deviation. If the frequency deviation compensation mechanism is not adopted, the satellite-to-ground processing system needs to search in a large frequency deviation range, which will greatly consume limited processing resources. Therefore, by estimating the size of Doppler and taking pre-adjustment measures, the demand for processing resources can be reduced.

[0074] A method for directly connecting to a polar-orbiting meteorological satellite provided by the present invention comprises:

[0075] Step S1: Pre-store meteorological satellite orbit parameters in a lightweight form. The specific method of pre-store meteorological satellite orbit parameters in a lightweight form is: pre-store the local time T0 of the ascending / descending node of the meteorological satellite to be connected, the orbit period T, the orbit height h, the longitude λ0 and latitude of the satellite's sub-satellite point at a certain time t0 And the satellite's corresponding ascending / descending orbit attribute k. Among them, T0, T, h, t0, λ0, The ascending / descending track attribute k is stored as a signed integer, with the ascending track being 1 and the descending track being -1.

[0076] Step S2: Calculate the time window of the polar-orbiting meteorological satellite transit according to the meteorological satellite orbit parameters. Step S2 includes:

[0077] Step S2.1: Use Beidou / GPS device to obtain the longitude λ1 and latitude of the current location and the current time t1.

[0078] Step S2.2: Estimate satellite arrival latitude The time series t m , the calculation formula is as follows:

[0079]

[0080] In the formula, represents the latitude of the satellite's subsatellite point at time t0, and m represents the arrival latitude The serial number of T represents the orbital period of the meteorological satellite to be connected that is stored in advance.

[0081] Step S2.3: Estimate the m The longitude of the satellite subsatellite point at this time m , the calculation formula is as follows:

[0082] λ m =λ0-2π(t m -t0) / 24h

[0083] Where λ0 represents the longitude of the satellite's sub-satellite point at time t0, and 24h represents 24 hours.

[0084] Step S2.4: Estimate the m The distance d between the satellite and the current location at this moment m , the calculation formula is as follows:

[0085]

[0086] In the formula, R represents the radius of the earth, and R=6400km.

[0087] Step S2.5: Estimate the mThe angle θ between the satellite and the current location at this moment m , the calculation formula is as follows:

[0088]

[0089] Step S2.6: When θ m Greater than the preset threshold θ t When , it means the satellite is visible to the location, otherwise it is invisible.

[0090] Step S3: estimating the frequency deviation of the polar-orbiting meteorological satellite signal and performing frequency deviation compensation. Step S3 includes:

[0091] Step S3.1: Estimate the maximum Doppler frequency shift Δf m , the calculation formula is as follows:

[0092]

[0093] In the formula, f0 represents the carrier frequency, g represents the gravitational acceleration, θ m Indicates t m The angle between the satellite and the current location at this moment, R represents the radius of the earth, c represents the speed of light, and h represents the orbital altitude of the satellite.

[0094] Step S3.2: Estimate the transit time t, calculated as follows:

[0095]

[0096] Step S4: completing frequency offset compensation, sending access information, and capturing polar-orbiting meteorological satellite signals. Step S4 includes:

[0097] Step S4.1: In the local signal carrier, set the frequency offset to Δf when the satellite enters m , set the frequency deviation to -Δf when the satellite leaves the country m , and for Δf m ~-Δf m Linear interpolation is performed to generate a frequency deviation-time table with a time accuracy of 5s.

[0098] Step S4.2: According to the frequency deviation-timetable, the frequency signal of the access satellite is adjusted to send an access request instruction.

[0099] Step S4.3: According to the frequency deviation-timetable, the local carrier signal of the receiving satellite is adjusted to capture the downlink return command of the satellite.

[0100] Step S4.4: Confirm that the reply format meets the requirements, and adjust the uplink frequency signal according to step S4.2 to send a confirmation instruction.

[0101] Step S4.5: Adjust the local carrier signal according to step S4.3 to complete the capture of the downlink signal.

[0102] Step S4.6: Use the local tracking loop to track the satellite carrier signal and generate a carrier offset.

[0103] Step S5: Request polar-orbiting meteorological satellite data according to the carrier offset. Step S5 includes:

[0104] Step S5.1: Generate carrier offset based on the satellite carrier signal tracked by the local tracking loop, adjust the uplink frequency signal, and send a regional product request instruction.

[0105] Step S5.2: The satellite receives the product request instruction and sends the corresponding product.

[0106] Step S5.3: Complete the product reception and push it to the mobile phone via Bluetooth.

[0107] Step S6: receiving the polar-orbiting meteorological satellite data, wherein the polar-orbiting meteorological satellite data includes message information and orbital parameters sent by the polar-orbiting meteorological satellite.

[0108] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0109] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A handheld terminal directly connected to a polar-orbiting meteorological satellite, characterized in that: include: Multifunctional system-on-chip, high-speed agile transceiver, display screen; The satellite uplink signal and downlink signal are obtained and processed by the duplexer, then transmitted to the high-speed agile transceiver for frequency conversion and conversion processing, and then interact with the multi-functional system-on-chip to complete the satellite transit window calculation and parameter adjustment, and are displayed to the user through the display screen.

2. The handheld terminal for directly connecting to polar-orbiting meteorological satellites according to claim 1, characterized in that: The multifunctional on-chip system is responsible for the control of the entire terminal, completing satellite transit window calculation, parameter adjustment, request and reception of satellite products, Bluetooth and storage management.

3. The handheld terminal for directly connecting to polar-orbiting meteorological satellites according to claim 1, characterized in that: The high-speed agile transceiver performs down-conversion and analog-to-digital conversion of satellite downlink signals and up-conversion and digital-to-analog conversion of terminal uplink signals; The display screen displays the products sent by the satellite and the status of the handheld terminal itself.

4. The handheld terminal for directly connecting to polar-orbiting meteorological satellites according to claim 1, characterized in that: Also includes: Duplexer, receiving channel, transmitting channel, memory, buttons and Bluetooth module; The duplexer completes the composite antenna transmission of the satellite downlink signal and the handheld terminal uplink signal; The receiving channel completes filtering and amplification of satellite downlink signals; The sending channel completes filtering and amplification of the terminal uplink signal; The memory completes the storage of satellite orbit parameters and issued products; The button is used to set the mode of the handheld terminal; The Bluetooth module is used for communication with third-party devices.

5. The handheld terminal directly connected to a polar-orbiting meteorological satellite according to claim 1, characterized in that: Also includes: Lithium battery, charge and discharge management module and composite interface; The lithium battery and the charge and discharge management module are used for charge management, discharge management and level conversion; The composite interface is used for inputting power, interacting with external data signals, and charging third-party devices.

6. A method for directly connecting to a polar-orbiting meteorological satellite, characterized in that: Using the handheld terminal for directly connecting to a polar-orbiting meteorological satellite as described in any one of claims 1 to 5, the method for directly connecting to a polar-orbiting meteorological satellite comprises: Step S1: pre-storing meteorological satellite orbit parameters in a lightweight form; Step S2: Calculating the time window of the polar-orbiting meteorological satellite transit according to the meteorological satellite orbit parameters; Step S3: estimating the frequency deviation of the polar-orbiting meteorological satellite signal and performing frequency deviation compensation; Step S4: completing frequency offset compensation, sending access information, and capturing polar-orbiting meteorological satellite signals; Step S5: Requesting polar-orbiting meteorological satellite data according to the carrier offset; Step S6: receiving the polar-orbiting meteorological satellite data, wherein the polar-orbiting meteorological satellite data includes message information and orbital parameters sent by the polar-orbiting meteorological satellite.

7. The method for directly connecting to a polar-orbiting meteorological satellite according to claim 1, characterized in that: The step S2 comprises: Step S2.1: Use Beidou / GPS device to obtain the longitude λ1 and latitude of the current location and the current time t1; Step S2.2: Estimate satellite arrival latitude The time series t m , the calculation formula is as follows: In the formula, represents the latitude of the satellite's subsatellite point at time t0, and m represents the arrival latitude The serial number of T represents the orbital period of the meteorological satellite to be connected stored in advance; Step S2.3: Estimate the m The longitude of the satellite subsatellite point at this time m , the calculation formula is as follows: l m =λ0-2π(t m -t0) / 24h Where λ0 represents the longitude of the satellite's sub-satellite point at time t0; Step S2.4: Estimate the m The distance d between the satellite and the current location at this moment m , the calculation formula is as follows: Where R represents the radius of the earth; Step S2.5: Estimate the m The angle θ between the satellite and the current location at this moment m , the calculation formula is as follows: Step S2.6: When θ m Greater than the preset threshold θ t When , it means the satellite is visible to the location, otherwise it is invisible.

8. The method for directly connecting to a polar-orbiting meteorological satellite according to claim 1, characterized in that: The step S3 comprises: Step S3.1: Estimate the maximum Doppler frequency shift Δf m , the calculation formula is as follows: In the formula, f0 represents the carrier frequency, g represents the gravitational acceleration, θ m Indicates t m The angle between the satellite and the current location at the moment, R represents the radius of the earth, c represents the speed of light, and h represents the orbital height of the satellite; Step S3.2: Estimate the transit time t, calculated as follows:

9. The method for directly connecting to a polar-orbiting meteorological satellite according to claim 1, characterized in that: The step S4 comprises: Step S4.1: In the local signal carrier, set the frequency offset to Δf when the satellite enters m , set the frequency deviation to -Δf when the satellite leaves the country m , and for Δf m ~-Δf m Perform linear interpolation to generate a frequency deviation-timetable; Step S4.2: adjusting the frequency signal of the access satellite to send an access request instruction according to the frequency deviation-timetable; Step S4.3: According to the frequency deviation-timetable, adjusting the local carrier signal of the receiving satellite to capture the satellite downlink return command; Step S4.4: confirm that the reply format meets the requirements, and adjust the uplink frequency signal according to step S4.2 to send a confirmation instruction; Step S4.5: adjusting the local carrier signal according to step S4.3 to complete the capture of the downlink signal; Step S4.6: Use the local tracking loop to track the satellite carrier signal and generate a carrier offset.

10. The method for directly connecting to a polar-orbiting meteorological satellite according to claim 1, characterized in that: The step S5 comprises: Step S5.1: Generate a carrier offset according to the satellite carrier signal tracked by the local tracking loop, adjust the uplink frequency signal, and send a regional product request instruction; Step S5.2: The satellite receives the product request instruction and sends the corresponding product; Step S5.3: Complete the product reception and push it to the mobile phone via Bluetooth.

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