A method and device and equipment for calibrating the gain of the reflection channel of an occultation detector

Abstract

An embodiment of the present invention provides a method, device, and equipment for calibrating the gain of the reflection channel of an occultation detector. The method includes: under preset ambient temperature conditions, inputting two or more calibration sources into the reflection channel of the occultation detector respectively, and outputting the DDM noise observation values corresponding to each calibration source; obtaining the gain deviation values caused by the deviation of the AD sampling values of each calibration source from the target values; determining the equivalent noise temperature corresponding to each calibration source, and determining the equivalent input noise power based on the equivalent noise temperature; determining the total gain of the reflection channel of the occultation detector and the system noise figure based on the DDM noise observation values, the gain deviation values, and the equivalent input noise power. Through the embodiment of the present invention, the calibration of the gain of the reflection channel of the occultation detector is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and particularly to a method and device and equipment for calibrating the gain of a reflection channel of a occultation sounder. Background Art

[0002] A GNSS-R (Global Navigation Satellite System - Reflectometry) occultation sounder is an instrument for detecting the Earth's atmosphere and ocean environment by using Global Navigation Satellite System (GNSS) signals. It receives GNSS satellite signals reflected by the Earth's atmosphere or ocean surface to invert relevant physical parameters of the atmosphere and ocean.

[0003] Measuring the sea surface wind field by using GNSS reflected signals is one of the main tasks and functions of a GNSS-R occultation sounder. This function requires pre-launch calibration of the gain and noise figure of the reflection channel of the GNSS-R occultation sounder to calculate the absolute power of the reflected signal and noise corresponding to the on-board GNSS-R DDM (Delay-Doppler Mapping) waveform.

[0004] For measuring the sea surface wind field, accurate calibration of the reflection channel gain and noise figure is crucial. When measuring the sea surface wind field by using GNSS-R signals, it is necessary to accurately know the absolute power of the reflected signal. The power of the reflected signal is closely related to the sea surface roughness, and the sea surface roughness is affected by the sea surface wind field. By calculating the absolute power of the reflected signal and noise, the information of the sea surface wind field can be inverted more accurately. If the gain calibration is inaccurate, it will lead to an incorrect estimation of the reflected signal power, and thus a large error will be generated in the wind field inversion process. Similarly, inaccurate calibration of the noise figure will affect the extraction of the true reflected signal because in the actual measurement environment, the signal is received mixed with noise. Summary of the Invention

[0005] In view of the above problems, a method and device and equipment for calibrating the gain of a reflection channel of an occultation sounder are provided to overcome or at least partially solve the above problems, including:

[0006] A method for calibrating the gain of a reflection channel of an occultation sounder, the method comprising:

[0007] Under preset ambient temperature conditions, input two or more calibration sources into the reflection channel of the occultation sounder respectively, and output the DDM noise observation values corresponding to each calibration source;

[0008] Obtain the gain deviation values caused by the deviation of the AD sampling value of each calibration source from the target value;

[0009] Determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature;

[0010] Determine the total gain of the reflection channel of the occultation detector and the system noise figure based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power.

[0011] In an embodiment of the present invention, the determining the total gain of the reflection channel of the occultation detector and the system noise figure based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power includes:

[0012] Determine the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent noise temperature;

[0013] Determine the system noise figure based on the system noise power.

[0014] In an embodiment of the present invention, the determining the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power includes:

[0015] Combine the DDM noise observation value, the gain deviation value, and the equivalent input noise power with a preset reflection channel calibration formula to determine the total channel gain and the system noise power. The preset reflection channel calibration formula is used to describe the numerical relationship between the DDM noise observation value, the gain deviation value, the equivalent input noise power, the total channel gain, and the system noise power.

[0016] In an embodiment of the present invention, the reflection channel calibration formula is:

[0017] DDM noise observation value = (total channel gain + gain deviation value) * (equivalent input noise power + system noise power).

[0018] In an embodiment of the present invention, the determining the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power includes:

[0019] When there are more than two calibration sources, determine a set of candidate calibration values based on the DDM noise observation values, the gain deviation values, and the input noise powers of any two calibration sources. The candidate calibration values include the candidate total channel gain and the candidate system noise power;

[0020] Take the average value of the candidate total channel gains in multiple sets of candidate calibration values as the total channel gain corresponding to the multiple sets of calibration sources;

[0021] Taking the average value of the candidate system noise power among multiple groups of candidate calibration values as the system noise power corresponding to the multiple groups of calibration sources;

[0022] In an embodiment of the present invention, determining the system noise figure based on the system noise power includes:

[0023] Obtaining the Boltzmann constant, the noise reference temperature, and the system bandwidth constant;

[0024] Determining the product value of the Boltzmann constant, the noise reference temperature, and the system bandwidth constant;

[0025] Determining the quotient value of the system noise power and the product value;

[0026] Adding the quotient value to a preset constant value to obtain the system noise figure.

[0027] In an embodiment of the present invention, the calibration source is any one of the following:

[0028] Blackbody, liquid nitrogen, noise source.

[0029] An occultation detector reflection channel gain calibration device, the device includes:

[0030] A noise observation value determination module, configured to input two or more calibration sources into the occultation detector reflection channel respectively under a preset ambient temperature condition, and output the DDM noise observation value corresponding to each calibration source;

[0031] A gain deviation value acquisition module, configured to acquire the gain deviation value caused by the AD sampling value of each calibration source deviating from the target value;

[0032] A noise power determination module, configured to determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature;

[0033] A calibration data determination module, configured to determine the total gain of the occultation detector reflection channel and the system noise figure based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power.

[0034] An electronic device, including a processor, a memory, and a computer program stored on the memory and capable of running on the processor, where when the computer program is executed by the processor, it implements the above-mentioned occultation detector reflection channel gain calibration method.

[0035] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the above-mentioned occultation detector reflection channel gain calibration method.

[0036] The embodiments of the present invention have the following advantages:

[0037] In the embodiments of the present invention, under the condition of a preset ambient temperature, two or more calibration sources are respectively input into the reflection channel of the occultation detector, and the DDM noise observation values corresponding to each calibration source are output.

[0038] The gain deviation values caused by the deviation of the AD sampling value of each calibration source from the target value are obtained; the equivalent noise temperature corresponding to each calibration source is determined, and the equivalent input noise power is determined based on the equivalent noise temperature; the total gain of the reflection channel of the occultation detector and the system noise figure are determined based on the DDM noise observation values, the gain deviation values, and the equivalent input noise power, realizing the calibration of the gain of the reflection channel of the occultation detector. Description of the Drawings

[0039] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for the description of the present invention will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0040] Figure 1 is a flowchart of the steps of a method for calibrating the gain of the reflection channel of an occultation detector provided by an embodiment of the present invention;

[0041] Figure 2 is a flowchart of the steps of another method for calibrating the gain of the reflection channel of an occultation detector provided by an embodiment of the present invention;

[0042] Figure 3a is a schematic diagram of the principle block of a reflection channel calibration system provided by an embodiment of the present invention;

[0043] Figure 3b is a schematic diagram of the principle block of another reflection channel calibration system provided by an embodiment of the present invention;

[0044] Figure 3c is a general test principle block provided by an embodiment of the present invention;

[0045] Figure 4 is a schematic structural diagram of an apparatus for calibrating the gain of the reflection channel of an occultation detector provided by an embodiment of the present invention. Detailed Embodiments

[0046] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0047] Currently, since signals and noise coexist in the reflection channel of the occultation sounder, it is difficult to accurately estimate the noise observation value after the occultation sounder is launched.

[0048] In the embodiments of the present invention, to ensure that various values of the reflection channel of the occultation sounder can be accurately calculated after the occultation sounder is launched, a preset calibration source can be used to perform calibration calculations on the total gain of the reflection channel and the system noise coefficient of the occultation sounder reflection channel.

[0049] Refer to Figure 1 , which shows a flowchart of the steps of a method for calibrating the gain of the reflection channel of an occultation sounder provided by an embodiment of the present invention, and specifically may include the following steps:

[0050] Step S101, under the condition of a preset ambient temperature, input two or more calibration sources into the reflection channel of the occultation sounder respectively, and output the DDM noise observation values corresponding to each calibration source;

[0051] In the embodiments of the present invention, a calibration source can be selected under the condition of a preset ambient temperature, and the calibration calculation of the reflection channel gain can be performed based on the selected calibration source. A calibration source is a reference source used to calibrate or test a measuring device, instrument, or system. The calibration source can provide known and stable signals or physical quantities to ensure the accuracy and reliability of the device. The calibration source selected in the embodiments of the present invention can be any one of the following: blackbody, liquid nitrogen, noise source. It should be noted that in addition to the above examples, other substances that meet the characteristics of the calibration source can also be selected as the calibration source.

[0052] After two or more calibration sources are selected, the calibration sources can be input into the reflection channel of the occultation sounder under the condition of a preset ambient temperature, and then the DDM noise observation values corresponding to each calibration source can be measured. Among them, the preset temperature environment is used to simulate the temperature of the occultation sounder and can be set according to actual needs. For example, when the temperature at the time of launching the occultation sounder this time is T1, then when performing data calibration before launching, indoor simulation tests can be carried out in accordance with T1 to determine the DDM noise observation values corresponding to each calibration source in the T1 environment. When the temperature at the time of launching the occultation sounder this time is T2, then when performing data calibration before launching, indoor simulation tests can be carried out in accordance with T2 to determine the DDM noise observation values corresponding to each calibration source in the T2 environment.

[0053] In the embodiment of the present invention, data calibration is realized through a calibration source with known parameters under indoor simulation conditions before the occultation detector is launched.

[0054] Step S102: Obtain the gain deviation value caused by each calibration source when the AD sampling value deviates from the target value.

[0055] After determining the calibration source, the gain deviation value caused by each calibration source when the AD sampling value deviates from the target value can be determined according to the type of the calibration source. There is a corresponding relationship among the calibration source, the deviation of the AD sampling value from the target value, and the gain deviation value. The target value in the deviation of the AD sampling value from the target value can be set according to actual needs. For example, the gain deviation value caused when the AD sampling value deviates from the target value by 13.5, and the actual gain deviation value caused when the AD sampling value deviates from the target value by 13.5.

[0056] In practical applications, the gain deviation value caused when the AD sampling value deviates from the target value can be obtained through calibration inside the reflection channel of the detector.

[0057] Step S103: Determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature.

[0058] In practical applications, there is a corresponding relationship among the calibration source, the equivalent noise temperature, and the equivalent input noise power. Therefore, after determining the calibration source, the equivalent noise temperature can also be determined according to the type of the calibration source, and then the equivalent input noise efficiency can be determined based on the equivalent noise temperature.

[0059] For example, the equivalent noise temperature of liquid nitrogen is 80K, and the corresponding equivalent input noise power is -179.6 dBW; the equivalent noise temperature of the matched load is 328K, and the corresponding equivalent input noise power is -173.4 dBW; the equivalent noise temperature of the noise source is 8283.6K, and the corresponding equivalent input noise power is -159.4 dBW.

[0060] Step S104: Determine the total gain of the reflection channel of the occultation detector and the system noise figure based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power.

[0061] According to the foregoing introduction, determine the DDM noise observation value, the gain deviation value, and the equivalent input noise power, then the unknown total gain of the reflection channel of the occultation detector and the system noise figure can be determined by combining the known DDM noise observation value, the gain deviation value, and the equivalent input noise power. Specifically, in the embodiment of the present invention, there are two unknown calibration values, namely the total gain of the reflection channel of the occultation detector and the system noise figure. Therefore, at least two calibration source combinations are required to realize the calibration of the unknown quantity.

[0062] In an embodiment of the present invention, under preset ambient temperature conditions, two or more calibration sources are respectively input into the reflection channel of the occultation detector, and the DDM noise observation values corresponding to each calibration source are output; the gain deviation values caused by the deviation of the AD sampling value from the target value for each calibration source are obtained; the equivalent noise temperature corresponding to each calibration source is determined, and the equivalent input noise power is determined based on the equivalent noise temperature; the total gain of the reflection channel of the occultation detector and the system noise figure are determined based on the DDM noise observation values, the gain deviation values, and the equivalent input noise power, thereby realizing the calibration of the gain of the reflection channel of the occultation detector.

[0063] Referring to Figure 2 , the flowchart of steps of another method for calibrating the gain of the reflection channel of the occultation detector provided by an embodiment of the present invention is shown, and specifically may include the following steps:

[0064] Step S201, under preset ambient temperature conditions, two or more calibration sources are respectively input into the reflection channel of the occultation detector, and the DDM noise observation values corresponding to each calibration source are output;

[0065] Step S202, obtain the gain deviation values caused by the deviation of the AD sampling value from the target value for each calibration source;

[0066] Step S203, determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature;

[0067] Step S204, determine the total channel gain and the system noise power based on the DDM noise observation values, the gain deviation values, and the equivalent noise temperature;

[0068] In practical applications, the unknown total channel gain and the system noise power can be determined according to the known DDM noise observation values, gain deviation values, and equivalent noise temperature determined by the calibration source.

[0069] In an embodiment of the present invention, the specific process of step S204 may be: combining the DDM noise observation values, the gain deviation values, and the equivalent input noise power with a preset calibration formula for the reflection channel to determine the total channel gain and the system noise power, and the preset calibration formula for the reflection channel is used to describe the numerical relationship between the DDM noise observation values, the gain deviation values, the equivalent input noise power, and the total channel gain and the system noise power.

[0070] Among them, the calibration formula for the reflection channel is:

[0071] DDM noise observation value = (total channel gain + gain deviation value) * (equivalent input noise power + system noise power).

[0072] In the above reflection channel calibration formula, the gain deviation value, DDM noise observation value and equivalent input noise power are all known quantities. The total channel gain and system noise power, each different calibration source can obtain a formula according to the above formula. Two or more calibration sources can be combined to resolve the two unknown quantities.

[0073] In one embodiment of the present invention, when there are two calibration sources, a set of solutions for two unknown quantities is obtained based on two known sets of numerical values.

[0074] In another embodiment of the present invention, when there are more than two calibration sources, a group of candidate calibration values ​​can be determined based on the DDM noise observation values, gain deviation values ​​and input noise powers of any two calibration sources, the candidate calibration values ​​including candidate channel total gains and candidate system noise powers; the average value of the candidate channel total gains in multiple groups of candidate calibration values ​​is used as the channel total gain corresponding to the multiple groups of calibration sources; the average value of the candidate system noise powers in the multiple groups of candidate calibration values ​​is used as the system noise power corresponding to the multiple groups of calibration sources.

[0075] The two unknown quantities in the embodiment of the present invention require at least two sets of data to determine. When there are more than two calibration sources, the data of any two calibration sources can be used to obtain a set of candidate system noise power and channel total gain.

[0076] Furthermore, the actual calibration data can be determined based on the obtained multiple groups of candidate system noise power and channel total gain. Specifically, the actual calibration data can be determined by averaging, that is, the average system noise power is obtained by adding up each candidate system noise power and dividing it by the number of groups, and the actual system noise power is obtained by adding up each channel total gain and dividing it by the number of groups, and the average channel total gain is obtained as the actual channel total gain.

[0077] For example, suppose that three calibration sources are used for calibration, among which, the relevant known data of calibration source 1 and calibration source 2 can obtain the first group of unknown quantities, namely, candidate system noise power 1 and channel total gain 1; the relevant known data of calibration source 1 and calibration source 3 can obtain the second group of unknown quantities, namely, candidate system noise power 2 and channel total gain 2; the relevant known data of calibration source 2 and calibration source 3 can obtain the third group of unknown quantities, namely, candidate system noise power 3 and channel total gain 3.

[0078] Then the system noise power = (candidate system noise power 1 + candidate system noise power 2 + candidate system noise power 3) / 3;

[0079] Total channel gain = (total channel gain 1 + total channel gain 2 + total channel gain 3) / 3.

[0080] Step S205: determining the system noise factor based on the system noise power.

[0081] After determining the system noise power, the actual system noise figure can be determined based on the system noise power according to the corresponding relationship between the system noise power and the system noise figure.

[0082] In an embodiment of the present invention, determining the system noise figure based on the system noise power includes: obtaining the Boltzmann constant, the noise reference temperature, and the system bandwidth constant; determining the product value of the Boltzmann constant, the noise reference temperature, and the system bandwidth constant; determining the quotient value of the system noise power and the product value; and adding the quotient value to a preset constant value to obtain the system noise figure.

[0083] In practical applications, the relationships among the noise power, the noise figure, and the noise temperature are as follows:

[0084]

[0085] Therefore,

[0086]

[0087] Among them, is the system noise figure of the reflection channel of the detector, k is the Boltzmann constant, T0 is the noise reference temperature, and B is the system bandwidth constant. The Boltzmann constant, the noise reference temperature, and the system bandwidth constant are fixed data after determining the calibration environment.

[0088] The embodiment of the present invention is different from the traditional system calibration research method. A gain calibration system and method for the reflection channel of a multi-calibration-source GNSS-R occultation detector according to the present invention provides a new error correction method for accurate height measurement of the system by accurately calibrating the total gain and noise figure of the system reflection channel, and further improves the height measurement accuracy. The present invention uses two or more calibration sources with different equivalent temperatures, and realizes high-precision calibration of the system by accurately controlling the environmental temperature and digital control AGC. Moreover, the present invention can perform pre-launch calibration on the reflection channel system, and can apply the calibration result to on-orbit data inversion, avoiding the complexity of on-orbit calibration.

[0089] Reference Figure 3a , is a schematic block diagram of a reflection channel calibration system implemented in the present invention. The reflection channel calibration system may include four parts: a reflection antenna, an LNA (low noise amplifier) and a filter, a down-conversion channel, and a baseband processing. Among them, the reflection antenna can be used to receive GNSS reflection signals, and the input power is Pin. The LNA and the filter are used to amplify the reflection signals received by the reflection antenna and filter out out-of-band interference signals. The down-conversion channel is used to perform down-conversion, intermediate frequency amplification, intermediate frequency filtering, and AD sampling on the signals of the amplifier and the filter. The baseband processing is used to capture, track, and solve the sampled digital intermediate frequency signals, and then output the DDM correlation power value (i.e., the DDM noise observation value of the input calibration source).

[0090] Reference Figure 3b As shown in the figure, it is a schematic diagram of the principle of another reflection channel calibration system for the implementation of the present invention. The detailed design circuit of the reflection channel may include a reflection antenna, a cavity filter, a first-stage LNA, a radio frequency filter, a second-stage LNA, downconversion, an intermediate frequency amplifier, an intermediate frequency filter, an AD, a baseband FPGA, a reflection DSP, etc.

[0091] The reflection antenna can be used to receive GNSS reflection signals and then transmit the signals to the cavity filter. The cavity filter filters the received reflection signals to remove out-of-band interference. The first-stage LNA amplifies the filtered signals with low noise and then transmits the signals to the radio frequency filter. The radio frequency filter can be used to suppress image interference. Then the signals enter the second-stage LNA for further amplification. The amplified signals enter the downconversion module. The oven-controlled crystal oscillator provides the system clock and inputs it to the phase-locked local oscillator source, and then outputs the local oscillator signal to provide the local oscillator signal for downconversion. The downconversion module performs frequency migration on the signals, downconverting the radio frequency signals into intermediate frequency signals, and then entering the intermediate frequency amplifier for intermediate frequency amplification. The intermediate frequency amplified signals enter the intermediate frequency filter for intermediate frequency filtering. The intermediate frequency filtered signals enter the AD for analog-to-digital conversion. The converted intermediate frequency digital signals enter the baseband FPGA for digital signal acquisition and tracking. The processed signals enter the reflection DSP for data inversion and calculation, and output the DDM correlation power value (i.e., the DDM noise observation value of the input calibration source).

[0092] Reference Figure 3c As shown in the figure, it is a schematic diagram of the overall test principle for the implementation of the present invention. The specific test process is as follows:

[0093] In this test, liquid nitrogen, a matched load, and a noise source are used as three input noise sources with known powers. Under the condition that the temperature of the incubator is controlled to an ambient temperature of 0°C to 45°C, the acquisition of the DDM signals of the reflection channel of the detector under different noise source conditions is completed. Finally, the calculation of the total link gain and equivalent noise coefficient of the receiver is completed through post-data processing.

[0094] There are three calibration working modes in the test: liquid nitrogen mode, matched load mode, and noise source mode. Under different test modes, the reflection channel is respectively connected to liquid nitrogen, a matched load, and a noise source signal.

[0095] The main body of the occultation detector is placed inside the high and low temperature chamber, and the ground equipment is placed outside the high and low temperature chamber. The GNSS signal simulator generates GNSS satellite signals, which are connected to the positioning and occultation channels of the occultation detector through a radio frequency power divider. The linear voltage regulator provides a +28V system power supply for the main body of the occultation detector. The main body of the occultation detector is connected to the ground test equipment through an interface module. The interface module transmits low-speed 422 data, high-speed 422 data, and 1553B data to the ground test equipment, and then transmits them to the data receiving PC through the USB bus for display and post-processing of data. The analog signal acquisition is measured using a multimeter.

[0096] It should be noted that, for the method embodiments, for the sake of simple description, they are expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of the present invention are not limited by the described action sequence, because according to the embodiments of the present invention, some steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily essential for the embodiments of the present invention.

[0097] Referring to Figure 4 , a schematic structural diagram of a gain calibration device for the reflection channel of an occultation detector provided by an embodiment of the present invention is shown, which may specifically include the following modules:

[0098] The noise observation value determination module 401 is configured to input two or more calibration sources into the reflection channel of the occultation detector under a preset environmental temperature condition, and output the DDM noise observation value corresponding to each calibration source;

[0099] The gain deviation value acquisition module 402 is configured to acquire the gain deviation value caused by the deviation of the AD sampling value of each calibration source from the target value;

[0100] The noise power determination module 403 is configured to determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature

[0101] The calibration data determination module 404 is configured to determine the total gain of the reflection channel of the occultation detector and the system noise coefficient based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power.

[0102] In an embodiment of the present invention, the calibration data determination module 404 may include:

[0103] The gain and power determination sub-module is configured to determine the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent noise temperature;

[0104] A noise system determination sub-module, configured to determine a system noise coefficient based on the system noise power.

[0105] In an embodiment of the present invention, when the noise system determination sub-module is used to determine the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power, it is specifically configured to: combine the DDM noise observation value, the gain deviation value, and the equivalent input noise power with a preset reflection channel calibration formula to determine the total channel gain and the system noise power, where the preset reflection channel calibration formula is used to describe the numerical relationship between the DDM noise observation value, the gain deviation value, the equivalent input noise power, the total channel gain, and the system noise power.

[0106] In an embodiment of the present invention, the reflection channel calibration formula is:

[0107] DDM noise observation value = (total channel gain + gain deviation value) * (equivalent input noise power + system noise power).

[0108] In an embodiment of the present invention, the calibration data determination module 404 may include:

[0109] A candidate calibration value determination sub-module, configured to, when there are more than two calibration sources, determine a set of candidate calibration values based on the DDM noise observation value, the gain deviation value, and the input noise power of any two calibration sources, where the candidate calibration values include a candidate total channel gain and a candidate system noise power;

[0110] A total gain determination sub-module, configured to use the average value of the candidate total channel gains in multiple sets of candidate calibration values as the total channel gain corresponding to the multiple sets of calibration sources;

[0111] A system noise power determination sub-module, configured to use the average value of the candidate system noise powers in multiple sets of candidate calibration values as the system noise power corresponding to the multiple sets of calibration sources.

[0112] In an embodiment of the present invention, the system noise power determination sub-module may include:

[0113] A basic coefficient determination unit, configured to obtain the Boltzmann constant, the noise reference temperature, and the system bandwidth constant;

[0114] A product value determination unit, configured to determine the product value of the Boltzmann constant, the noise reference temperature, and the system bandwidth constant;

[0115] A quotient value determination unit, configured to determine the quotient value of the system noise power and the product value;

[0116] A system noise figure determination unit for adding the quotient value to a preset constant value to obtain the system noise figure.

[0117] In an embodiment of the present invention, the calibration source is any one of the following:

[0118] Blackbody, liquid nitrogen, noise source.

[0119] In an embodiment of the present invention, under preset ambient temperature conditions, two or more calibration sources are respectively input into the reflection channel of the occultation detector, and the DDM noise observation values corresponding to each calibration source are output;

[0120] Obtain the gain deviation value caused by the deviation of the AD sampling value of each calibration source from the target value; determine the equivalent noise temperature corresponding to each calibration source, and determine the equivalent input noise power based on the equivalent noise temperature; determine the total gain and system noise figure of the reflection channel of the occultation detector based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power, thereby realizing the calibration of the gain of the reflection channel of the occultation detector.

[0121] An embodiment of the present invention further provides an electronic device, which may include a processor, a memory, and a computer program stored on the memory and capable of running on the processor. When the computer program is executed by the processor, the above-mentioned gain calibration method for the reflection channel of the occultation detector is realized.

[0122] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned gain calibration method for the reflection channel of the occultation detector is realized.

[0123] For the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For the relevant parts, refer to the partial description of the method embodiment.

[0124] Each embodiment in this specification is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0125] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a device, or a computer program product. Therefore, the embodiments of the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0126] Embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate a means for implementing the specified functions in one process Figure 1 or more processes and / or blocks Figure 1 or more blocks.

[0127] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing terminal device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction means, and the instruction means implements the specified functions in one process Figure 1 or more processes and / or blocks Figure 1 or more blocks.

[0128] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device, so that a series of operation steps are executed on the computer or other programmable terminal device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable terminal device provide steps for implementing the specified functions in one process Figure 1 or more processes and / or blocks Figure 1 or more blocks.

[0129] Although the preferred embodiments of the embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0130] Finally, it should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or terminal device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or terminal device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or terminal device comprising the said element.

[0131] The above provides a detailed introduction to a method and device, and equipment for calibrating the gain of the reflection channel of an occultation detector. In this text, specific examples are used to elaborate on the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for calibrating the gain of a reflection channel of an occultation detector, characterized in that: The method comprises: Under the preset ambient temperature conditions, two or more calibration sources are respectively input into the reflection channel of the occultation detector, and the DDM noise observation value corresponding to each calibration source is output; Obtain the gain deviation value caused by each calibration source when the AD sampling value deviates from the target value; Determine an equivalent noise temperature corresponding to each calibration source, and determine an equivalent input noise power based on the equivalent noise temperature; Determine the total gain and system noise coefficient of the occultation detector reflection channel based on the DDM noise observation value, the gain deviation value and the equivalent input noise power; Wherein, determining the total gain and system noise coefficient of the occultation detector reflection channel based on the DDM noise observation value, the gain deviation value and the equivalent input noise power includes: Determine the total channel gain and system noise power based on the DDM noise observation value, the gain deviation value and the equivalent noise temperature; determining a system noise figure based on the system noise power; Wherein, determining the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent input noise power includes: Determine the total channel gain and the system noise power by combining the DDM noise observation value, the gain deviation value, and the equivalent input noise power with a preset reflection channel calibration formula, wherein the preset reflection channel calibration formula is used to describe the numerical relationship between the DDM noise observation value, the gain deviation value, the equivalent input noise power, the total channel gain, and the system noise power; Wherein, the preset reflection channel calibration formula is: DDM noise observation value = (total channel gain + gain deviation value) * (equivalent input noise power + system noise power).

2. The method according to claim 1, characterized in that The determining of the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value and the equivalent input noise power comprises: When the number of calibration sources is greater than 2, a set of candidate calibration values ​​is determined based on the DDM noise observation values, the gain deviation value, and the input noise power of any two calibration sources, the candidate calibration values ​​including candidate channel total gain and candidate system noise power; Taking the average value of the total gains of the candidate channels in the multiple groups of candidate calibration values ​​as the total gains of the channels corresponding to the multiple groups of calibration sources; An average value of the candidate system noise powers in the multiple groups of candidate calibration values ​​is used as the system noise powers corresponding to the multiple groups of calibration sources.

3. The method according to claim 1, characterized in that The determining of the system noise factor based on the system noise power comprises: Get the Boltzmann constant, noise reference temperature, and system bandwidth constant; Determining a product value of the Boltzmann constant, the noise reference temperature, and the system bandwidth constant; Determining a quotient value of the system noise power and the product value; The system noise coefficient is obtained by adding the quotient value to a preset constant value.

4. The method according to claim 1, characterized in that: The calibration source is any one of the following: Black body, liquid nitrogen, noise source.

5. A device for calibrating the gain of a reflection channel of an occultation detector, characterized in that: The device comprises: The noise observation value determination module is used to input two or more calibration sources into the reflection channel of the occultation detector respectively under the preset ambient temperature condition, and output the DDM noise observation value corresponding to each calibration source; A gain deviation value acquisition module is used to gain acquire the gain deviation value caused by each calibration source when the AD sampling value deviates from the target value; A noise power determination module, used to determine an equivalent noise temperature corresponding to each calibration source, and determine an equivalent input noise power based on the equivalent noise temperature; A calibration data determination module, used to determine the total gain and system noise coefficient of the occultation detector reflection channel based on the DDM noise observation value, the gain deviation value and the equivalent input noise power; Wherein, the calibration data determination module includes: A gain and power determination submodule, configured to determine a total channel gain and a system noise power based on the DDM noise observation value, the gain deviation value, and the equivalent noise temperature; A noise system determination submodule, configured to determine a system noise factor based on the system noise power; Wherein, when the noise system determination submodule is used to determine the total channel gain and the system noise power based on the DDM noise observation value, the gain deviation value and the equivalent input noise power, it is specifically used to: combine the DDM noise observation value, the gain deviation value and the equivalent input noise power with a preset reflection channel calibration formula to determine the total channel gain and the system noise power, and the preset reflection channel calibration formula is used to describe the numerical relationship between the DDM noise observation value, the gain deviation value, the equivalent input noise power and the total channel gain and the system noise power; Wherein, the reflection channel calibration formula is: DDM noise observation value = (total channel gain + gain deviation value) * (equivalent input noise power + system noise power).

6. An electronic device, characterized in that: The invention comprises a processor, a memory and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the method for calibrating the gain of the reflection channel of the occultation detector as claimed in any one of claims 1 to 4 is implemented.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for calibrating the gain of a reflection channel of an occultation detector as claimed in any one of claims 1 to 4 is implemented.

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