Ionized layer time delay monitoring system and method

Abstract

The invention discloses an ionosphere time delay monitoring system and method, and belongs to the technical field of ionosphere time delay monitoring, and the ionosphere time delay monitoring system comprises a satellite and a monitoring station which are in communication connection. The satellite is used for sending at least three pseudo-range ranging signals to the monitoring station; the monitoring station is used for receiving each pseudo-range ranging signal, synchronously measuring a plurality of pseudo-range ranging values correspondingly obtained by each pseudo-range ranging signal, and determining the total electron number of the ionized layer on the ranging signal path between the satellite and the monitoring station based on the plurality of pseudo-range ranging values. The ionosphere time delay monitoring method provided by the invention has the advantages of high real-time performance, accurate monitoring result and the like.

Description

[0001] Cross-references

[0002] This disclosure claims application number 202410661173.1 filed on May 27, 2024 and entitled "A Kind of Ionization The entire contents of the Chinese patent application are hereby incorporated by reference. All are incorporated into this article. Technical Field

[0003] The present application relates to the technical field of ionospheric delay monitoring, and in particular to an ionospheric delay monitoring system and method. Background Art

[0004] Ionospheric delay is a major positioning error term in satellite navigation and positioning, and also has an important impact in the fields of satellite communications and satellite remote sensing. The International GPS Service (IGS) organization uses a large number of ground stations to observe dual-frequency pseudoranges, calculate the TEC values ​​of different ionospheric puncture points, and form data covering the global ionosphere for use by a wide range of users.

[0005] In the current field of ionospheric delay monitoring, multi-frequency pseudorange signals broadcast by navigation satellites are commonly used, two different pseudorange signals are selected for pseudorange measurement, and then the ionospheric TEC value (ionospheric total electron count) is calculated using the dual-frequency method.

[0006] However, currently navigation satellites broadcast pseudorange signals at three frequencies. How to fully utilize the pseudorange values ​​of the three frequencies to obtain a better total ionospheric electron number is a controversial issue.

[0007] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0008] The main purpose of the present application is to provide an ionospheric delay monitoring system and method, aiming to solve the problem that the existing pseudo-range measurement values ​​of at least three frequency points cannot be fully utilized to calculate the total number of ionospheric electrons.

[0009] To achieve the above-mentioned purpose, the present application also provides an ionospheric delay monitoring system, comprising a satellite and a monitoring station connected in communication; the satellite is used to send at least three pseudorange ranging signals to the monitoring station; the monitoring station is used to receive and synchronously measure each of the pseudorange ranging signals to obtain a plurality of pseudorange ranging values, and determine the total number of ionospheric electrons on the ranging signal path between itself and the satellite based on each of the pseudorange ranging values.

[0010] In addition, to achieve the above-mentioned purpose, the present application also provides an ionospheric delay monitoring method, which is applied to the ionospheric delay monitoring system described in any embodiment of the present application, and the method is executed by a monitoring station, and the method includes: obtaining x pseudorange ranging signals broadcast by the satellite, wherein x is a positive integer greater than or equal to 3; synchronously measuring each of the pseudorange ranging signals to obtain x pseudorange ranging values, and selecting y pseudorange ranging values ​​from the x pseudorange ranging values; or selecting y from the x pseudorange ranging signals for synchronous measurement to obtain y pseudorange ranging values; respectively using pseudorange ranging expressions The pseudorange measurement values ​​are represented by the formula; the y pseudorange measurement values ​​are divided into two groups, the first group includes m pseudorange measurement values, and the second group includes h pseudorange measurement values, wherein 3≤y≤x, m+h=y, y, m, h are all positive integers; the two groups of pseudorange measurement values ​​represented by each pseudorange measurement expression are respectively averaged to obtain a first corrected average pseudorange measurement value and a second corrected average pseudorange measurement value; the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station is determined based on the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value.

[0011] The ionospheric delay monitoring system and method provided in the present application provide a new signal structure and can accurately calculate the total number of ionospheric electrons. The monitoring station can obtain the pseudorange measurement signal at any time and calculate the real-time total number of ionospheric electrons based on the above method. It has the advantages of strong real-time performance and accurate monitoring results. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic diagram of the structure of an ionospheric delay monitoring system according to an embodiment of the present application;

[0013] Figure 2 is a structural block diagram of a satellite and a monitoring station according to an implementation mode of the present application;

[0014] Figure 3 This is a structural schematic diagram of an ionospheric delay monitoring system according to another embodiment of the present application;

[0015] Figure 4 Schematic diagram of the structure of an ionospheric delay monitoring system according to another embodiment of the present application;

[0016] Figure 5 The present invention is a flowchart of an ionospheric delay monitoring method according to one embodiment of the present application.

[0017] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] In related technologies, when a satellite and a ground station communicate by radio, the radio signal will generate delays when passing through the atmosphere, including ionospheric delays and tropospheric delays. When the signal carrier frequency is less than 30GHz, the delay of the troposphere to the radio signal is considered equal; while the delay of the ionosphere to the radio signal is inversely proportional to the square of the carrier frequency and proportional to the total number of ionospheric electrons on the path. The mathematical expression of the delay generated by the radio signal passing through the ionosphere can be:

[0020]

[0021] Where: dI is the time delay of the RF signal (i.e., radio signal) when it passes through the ionosphere path of the satellite-to-ground line (unit: meter); f is the carrier frequency of the radio signal (unit: Hertz); TEC is the total number of ionosphere electrons on the path between the satellite and the ground station (unit: electrons / square meter).

[0022] Obtaining ionospheric TEC values ​​is not only widely used in the field of satellite navigation, but also in satellite communications, satellite remote sensing and other fields.

[0023] Ionospheric delay is a major positioning error term in satellite navigation and positioning, and also has an important impact in satellite communications and satellite remote sensing. In the current field of ionospheric delay monitoring, multi-frequency ranging signals broadcast by navigation satellites are commonly used, and two different ranging signals are selected from them for pseudo-range measurement, and then the dual-frequency method is used to calculate the ionospheric TEC value.

[0024] Navigation satellites broadcast triple-frequency pseudorange signals. Currently, using dual-frequency pseudorange values ​​to obtain the total number of ionosphere electrons is a very mature technology both in theory and in engineering implementation. However, how to use triple-frequency pseudorange signals and three pseudorange ranging values ​​to obtain the total number of ionosphere electrons is a controversial issue. This application provides a method for calculating the total number of ionosphere electrons using at least three pseudorange values, wherein the simplest system is when the number of pseudorange ranging values ​​is 3.

[0025] In order to solve the above problems, the embodiment of the present application provides an ionospheric delay monitoring system. The following first describes the various parameters involved in the embodiment of the present application as follows:

[0026] m represents the number of the first group of pseudo-range measurement values; h represents the number of the second group of pseudo-range measurement values; k represents the serial number of the first group of pseudo-range measurement values; j represents the serial number of the second group of pseudo-range measurement values; y represents the total number of selected pseudo-range measurement values; x represents the total number of pseudo-range measurement signals or pseudo-range measurement values;

[0027] dρ(n) represents the pseudo-range measurement difference, unit: meter; ρ 1,mean (n) represents the first corrected average pseudorange measurement value, unit: meter; ρ 2,mean (n) represents the second corrected average pseudorange measurement value, unit: meter; ρ zi (n) represents the pseudo-range measurement value numbered i at the nth moment, in meters; R true,zi (n) represents the real space distance traversed by the pseudo-range measurement signal numbered i at the nth moment, in meters; I zi (n) represents the ionospheric delay of the pseudo-range signal numbered i at the nth time, in meters; T duiliu,zi (n) represents the tropospheric delay of the pseudo-range measurement signal numbered i at the nth moment, in meters; c represents the speed of light, in meters per second; δt s (n) represents the clock difference between the satellite and the system time at the nth moment, in seconds; δt z (n) represents the clock difference of the monitoring station at the nth moment relative to the system time, in seconds; sagnac zz (n) represents the Sagnac effect delay of the pseudo-range measurement signal at the nth moment, in meters; Re s (n) represents the relativistic delay of the satellite clock at the nth moment, in meters; X zi (n) represents the hardware device delay of the pseudo-range measurement signal numbered i at the nth moment, in meters. The hardware device delay of the pseudo-range measurement signal includes the transmission delay of the satellite for the pseudo-range measurement signal numbered i and the reception delay of the monitoring station for the pseudo-range measurement signal numbered i;

[0028] ρ zk (n),ρ zj (n) represents the pseudo-range measurement value numbered k or j at the nth moment, in meters; R true,zk (n), R true,zj (n) represents the real space distance that the pseudo-range measurement signals numbered k and j have traveled at the nth moment, in meters; I zk (n), I zj (n) represents the ionospheric delay of the pseudo-range measurement signal numbered k, j at the nth moment, in meters; T duiliu,zk (n), T duiliu,zj (n) represents the tropospheric delay of the pseudo-range measurement signal numbered k, j at the nth moment, in meters; X zk(n), X zj (n) represents the hardware device delay of the pseudo-range measurement signals numbered k and j at the nth moment, in meters. The hardware device delay of the pseudo-range measurement signals includes the transmission delay of the satellite for the pseudo-range measurement signals numbered k and j, and the reception delay of the monitoring station for the pseudo-range measurement signals numbered k and j;

[0029] Q ion represents the ionospheric delay coefficient, TEC(n) represents the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station at the nth moment, unit: electron / square meter;

[0030] f zk (n) represents the carrier frequency of the pseudo-range measurement signal numbered k at the nth time, in Hertz; f zj (n) represents the carrier frequency of the pseudo-range measurement signal numbered j at the nth moment, in Hertz.

[0031] Special mention: Q ion is the ionospheric delay coefficient, which is published by some international organizations. With the in-depth study of ionospheric delay, the ionospheric delay coefficient is becoming more and more accurate. The ionospheric delay coefficient used to be 40.28, 40.30, and is currently 40.309. There may be more accurate ionospheric delay coefficients in the future. This application does not specifically limit the ionospheric delay coefficient, and takes the latest published value. In this embodiment, Q ion The value is 40.309.

[0032] The ionospheric delay monitoring system and related methods provided in the embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0033] The present application provides an ionospheric delay monitoring system and method for at least three pseudo-range ranging signals. The simplest system form of the system is that the satellite broadcasts three pseudo-range ranging signals to obtain three pseudo-range ranging values, from which three pseudo-range ranging values ​​are selected for calculation. At this time, x=3, y=3, m=2, h=1, y=m+h. In order to illustrate the system and method, three pseudo-range ranging signals and corresponding three pseudo-range ranging values ​​are used for illustration.

[0034] Figure 1 Schematic diagram of the structure of the ionospheric delay monitoring system according to the embodiment of the present application, as shown in FIG. Figure 1 As shown, the system includes a satellite 100 and a monitoring station 200 which are in communication connection. The ionospheric delay monitoring system provided by this embodiment is described in detail below in conjunction with the accompanying drawings.

[0035] refer to Figure 1, the satellite 100 may send a first pseudo-range measurement signal, a second pseudo-range measurement signal, and a third pseudo-range measurement signal to the monitoring station 200. The monitoring station 200 receives the first pseudo-range measurement signal, the second pseudo-range measurement signal, and the third pseudo-range measurement signal, and synchronously measures the first pseudo-range measurement signal, the second pseudo-range measurement signal, and the third pseudo-range measurement signal to obtain a first pseudo-range measurement value, a second pseudo-range measurement value, and a third pseudo-range measurement value, and a total number of ionospheric electrons on the ranging signal path between the satellite 100 and the monitoring station 200 determined based on the first pseudo-range measurement value, the second pseudo-range measurement value, and the third pseudo-range measurement value.

[0036] The ionospheric delay monitoring system provided in the embodiment of the present application can be applied to aerospace systems, for example, satellite navigation, satellite communication, satellite remote sensing, satellite reconnaissance, and meteorological satellites. The embodiment of the present application only takes the monitoring station to determine the total number of ionospheric electrons on the ranging signal path as an example for exemplary description.

[0037] It is worth noting that in the embodiment of the present application, if the telemetry signal is a spread spectrum system, the telemetry signal sent by the telemetry unit in the satellite can be used as a pseudo-range measurement signal.

[0038] In addition, it is worth noting that the monitoring station 200 in the embodiment of the present application can be one or more. When there are multiple monitoring stations 200, the multiple monitoring stations 200 can each determine the total number of ionospheric electrons on the ranging signal path between themselves and the satellite 100.

[0039] In some embodiments, the carrier frequency of the first pseudorange ranging signal, the carrier frequency of the second pseudorange ranging signal, and the carrier frequency of the third pseudorange ranging signal are different from each other.

[0040] In some embodiments, the carrier frequency of the first pseudo-range measurement signal, the carrier frequency of the second pseudo-range measurement signal, and the carrier frequency of the third pseudo-range measurement signal are frequency-hopped according to a preset frequency-hopping pattern on the time axis. That is, the pseudo-range measurement signals at different times do not use the same fixed frequency, but use signals of different frequencies at different times. Frequency hopping of the signals in this way can improve the anti-interference ability of the signals and enhance the anti-interception ability of the signals.

[0041] Of course, the carrier frequency of the first pseudorange measurement signal, the carrier frequency of the second pseudorange measurement signal and the carrier frequency of the third pseudorange measurement signal may also remain unchanged for a long time, that is, the time interval between two frequency hoppings is infinite.

[0042] In addition, it should be noted that the pseudo-range ranging signal described in the embodiments of the present application refers to a modulated signal obtained by modulating the ranging code signal in the carrier signal. In some specific embodiments, the ranging code can be a pseudo code, a weil code, an M code, etc., and this application does not specifically limit the specific selection of the ranging code.

[0043] The specific process of the monitoring station 200 determining the total number of ionospheric electrons on the ranging signal path between the monitoring station 200 and the satellite 100 can be found in the introduction of the subsequent method embodiments, which will not be expanded here.

[0044] Figure 2 is a structural block diagram of a satellite and a monitoring station according to an implementation mode of the present application, such as Figure 2 As shown, the satellite 100 may include a pseudorange generating device 102 and a satellite time and frequency device 103. The pseudorange generating device 102 may generate and broadcast a first pseudorange ranging signal, a second pseudorange ranging signal and a third pseudorange ranging signal. The satellite time and frequency device 103 provides the pseudorange generating device 102 with a time and frequency signal.

[0045] The monitoring station 200 may include a pseudo-range measuring device 204, a processing device 202 and a monitoring time-frequency device 203. The pseudo-range measuring device 204 may receive a first pseudo-range measuring signal, a second pseudo-range measuring signal and a third pseudo-range measuring signal, and synchronously measure the first pseudo-range measuring signal, the second pseudo-range measuring signal and the third pseudo-range measuring signal to obtain a first pseudo-range measuring value, a second pseudo-range measuring value and a third pseudo-range measuring value. The pseudo-range measuring device 204 may include a receiving antenna and a receiver. The receiving antenna receives the pseudo-range measuring signal of the satellite and generates a pseudo-range measuring value by the pseudo-range measuring device. The monitoring time-frequency device 203 provides a time-frequency signal for the pseudo-range measuring device 204. The monitoring time-frequency device 203 may also provide a time-frequency signal for the processing device 202.

[0046] The processing device 202 establishes a communication connection with the pseudorange measurement device 204. The processing device 202 can also be used to obtain a first pseudorange measurement value, a second pseudorange measurement value, and a third pseudorange measurement value, and determine the total number of ionospheric electrons on the ranging signal path between the satellite 100 and the monitoring station 200 based on the first pseudorange measurement value, the second pseudorange measurement value, and the third pseudorange measurement value.

[0047] It should be noted that the three pseudo-range measuring devices 204 in the embodiment of the present application can be independently set, or can also be integrated into one hardware device, that is, the functions of the three pseudo-range measuring devices 204 are realized by one hardware device, which all belong to the protection scope of the present application. And it can be understood that the pseudo-range measuring device 204, the processing device 202 and the monitoring time and frequency device 203 in the monitoring station 200 are modules divided by function, and specifically in hardware implementation, they can be implemented separately or integrated into one device, which all belong to the protection scope of the present application.

[0048] In some embodiments, the monitoring station 200 may include one or more pseudorange measuring devices 204; illustratively, when there are three pseudorange measuring devices 204, one pseudorange measuring device 204 receives a first pseudorange measuring signal and determines a first pseudorange measuring value based on the first pseudorange measuring signal, another pseudorange measuring device 204 receives a second pseudorange measuring signal and determines a second pseudorange measuring value based on the second pseudorange measuring signal, and another pseudorange measuring device 204 receives a third pseudorange measuring signal and determines a third pseudorange measuring value based on the third pseudorange measuring signal, and the three pseudorange measuring devices 204 are set with a zero baseline.

[0049] It is worth pointing out that the zero baseline setting mentioned in this application does not mean that the distance between the three pseudo-range measuring devices is 0, but that the distance setting between the three pseudo-range measuring devices must satisfy that the spatial paths experienced by the pseudo-range measuring signals received by each pseudo-range measuring device are approximately the same. When the distance between the three pseudo-range measuring devices becomes smaller and smaller, when they become one device or integrated into one chip, the approximately same gradually becomes the same, with the same satellite-to-ground space distance, the same tropospheric delay, and the same total number of ionospheric electrons.

[0050] In some embodiments, the three pseudo-range measuring devices 204 use the same time-frequency system, and synchronously measure the first pseudo-range measuring signal, the second pseudo-range measuring signal, and the third pseudo-range measuring signal at a preset time interval to obtain the first pseudo-range measuring value, the second pseudo-range measuring value, and the third pseudo-range measuring value. This allows the three pseudo-range measuring devices 204 to perform measurements at the same time to obtain the pseudo-range measuring values ​​at the same time. In actual use, the preset time interval can be set to 1s, for example, and the pseudo-range measuring devices 204 perform measurements at the rising edge or falling edge of their respective 1PPS (1Pulse Per Second) signals.

[0051] In some embodiments, the pseudorange generating device 102 has a transmission delay, and the pseudorange ranging device 204 of the monitoring station 200 has a receiving delay; wherein the pseudorange ranging signal transmission delay refers to the delay generated by the satellite pseudorange generating device 102 in the process of generating and transmitting the pseudorange ranging signal. The transmission delay of the pseudorange generating device 102 can be transmitted through the pseudorange ranging signal. Alternatively, the processing device 202 is preset with the transmission delay of the pseudorange generating device 102 and the receiving delay of the pseudorange ranging device 204.

[0052] By loading the pseudorange ranging signal transmission delay into the pseudorange ranging signal and transmitting it to the monitoring station, the existing signal between the satellite and the monitoring station is fully utilized to transmit the pseudorange ranging signal transmission delay. There is no need to set up an additional communication link, so no additional communication resources are occupied, which can greatly reduce communication costs and save frequency resources.

[0053] It is worth noting that the above embodiments are only described by using the monitoring station and the satellite's own signals (pseudo-range ranging signals broadcast by the pseudo-range generating device 102) to transmit the pseudo-range ranging signal transmission delay as an example. In other embodiments of the present application, the monitoring station and the satellite can also use additional communication signals to transmit the pseudo-range ranging signal transmission delay. For example, a telemetry unit can be provided in the satellite, and the pseudo-range ranging signal transmission delay can be transmitted by the telemetry signal broadcast by the telemetry unit, or the pseudo-range ranging signal transmission delay can be transmitted to the monitoring station through other user-defined communication link signals. The present application does not specifically limit the specific signal used to transmit the pseudo-range ranging signal transmission delay.

[0054] Figure 3 FIG. 1 is a schematic diagram of the structure of an ionospheric delay monitoring system according to another embodiment of the present application. Figure 3 As shown, the ionospheric delay monitoring system may further include a central station 210 , wherein the central station 210 is in communication connection with the monitoring station 200 ; the central station 210 may obtain monitoring parameters of the monitoring station 200 based on the communication results with the monitoring station 200 .

[0055] Specifically, the central station 210 can be located on the ground or integrated into a satellite, and the monitoring station 200 and the central station 210 can be directly connected in communication. For example, in a city, the monitoring station 200 and the central station 210 can communicate directly through a 4G network or a 5G network. Of course, the monitoring station 200 can also be connected in communication with the central station 210 through a satellite 100. For example, at sea or in a desert, the central station 210 and the monitoring station 200 both communicate directly through the satellite 100, thereby realizing communication between the monitoring station 200 and the central station 210 through the satellite 100.

[0056] In addition, continue to refer to Figure 3 When the central station 210 is connected to the monitoring station 200 for communication via the satellite 100, there may be a main feeder link between the central station 210 and the satellite 100, and there may be a slave feeder link between the monitoring station 200 and the satellite 100; wherein the main feeder link includes a main feeder link uplink signal and a main feeder link downlink signal, and the slave feeder link includes a slave feeder link uplink signal and a slave feeder link downlink signal, the main feeder link uplink signal and the slave feeder link downlink signal constitute a forward communication link, and the main feeder link downlink signal and the slave feeder link uplink signal constitute a return communication link.

[0057] Specifically, taking the case where the central station 210 is located on the ground as an example, during the communication process between the central station 210 and the monitoring station 200, the central station 210 broadcasts the main feed link uplink signal fu1 to the satellite 100. After receiving the uplink communication signal fu1, the satellite 100 forwards the signal to obtain the slave feed link downlink signal fd2 and transmits the downlink communication signal fd2 to the monitoring station 200. The monitoring station 200 broadcasts the slave feed link uplink signal fu2 to the satellite 100. After receiving the uplink communication signal fu2, the satellite 100 forwards the signal to obtain the main feed link downlink signal fd1 and transmits the downlink communication signal fd1 to the central station 210. The monitoring station 200 and the central station 210 communicate with each other through forwarding by the satellite 100, and the satellite 100 does not need to perform modulation, demodulation and other processing on the signal. In this way, the communication between the monitoring station 200 and the central station 210 can simplify the structure of the satellite 100, reduce the complexity of the satellite 100, and further reduce the cost of the satellite 100. Of course, it should be understood that when the central station 210 is integrated into the satellite, Figure 3 The main feed link and the slave feed link in the system are combined into one.

[0058] In this embodiment, the monitoring station 200 can exchange data with the central station 210 based on the communication link, so that the central station 210 can obtain other parameters such as the total number of ionosphere electrons of each monitoring station 200. The central station 210 summarizes the total number of ionosphere electrons of each monitoring station 200, processes it accordingly, and then publishes it, thereby improving positioning and navigation accuracy. For the method for determining the total number of ionosphere electrons, please refer to the introduction of the subsequent method embodiment, which will not be expanded here.

[0059] In some embodiments, there is also a pseudo-range measurement signal link between the monitoring station 200 and the satellite 100, and the pseudo-range measurement signal link includes three pseudo-range measurement signals; wherein the carrier frequency of the downlink signal from the feeder link can be the same as the carrier frequency of any of the pseudo-range measurement signals; or different from the carrier frequencies of the three pseudo-range measurement signals.

[0060] Specifically, when the carrier frequency of the pseudo-range ranging signal is different from the carrier frequency of the downlink signal of the slave feeder link, that is, the pseudo-range ranging signal and the downlink signal of the slave feeder link use different carrier frequencies. When the carrier frequency of the pseudo-range ranging signal is the same as the carrier frequency of the downlink signal of the slave feeder link, that is, the pseudo-range ranging signal is combined with the downlink signal of the slave feeder link, and the code division multiple access technology is used for communication, so that frequency resources can also be saved and the use and operation cost of the equipment can be reduced.

[0061] The monitoring station 200 in the embodiment of the present application may be a base station, a radar, etc. Figure 4As shown, the number of monitoring stations 200 in the embodiment of the present application can be one or more. For example, by deploying multiple monitoring stations 200 covering the world, the country, or different cities, each monitoring station 200 can monitor the ionospheric delay within its coverage area, and each monitoring station 200 communicates with the central station 210 to send the ionospheric delay of its respective monitoring area to the central station 210, so that the central station 210 can obtain the ionospheric delay of different locations around the world or the country. When performing navigation or remote sensing monitoring, the corresponding equipment manufacturer or user can obtain the corresponding ionospheric delay according to its own regional location to perform position correction and improve navigation and positioning accuracy.

[0062] In addition, when there are multiple monitoring stations 200 , some or all of the multiple monitoring stations 200 can communicate directly with the central station 210 , or some or all of the multiple monitoring stations 200 can communicate indirectly with the central station 210 via the satellite 100 .

[0063] It should be understood that in this exemplary embodiment, the central station 210 communicates with the monitoring station 200 to control the monitoring station 200 to perform corresponding actions. Typically, an Internet of Things system can be constructed based on the communication system provided in the embodiment of the present application. The specific content of the operating parameters can be determined according to the needs of the user. For example, the operating parameters may include the location information of the monitoring station 200, the current temperature information of the location of the monitoring station 200, etc.

[0064] On the basis of the above embodiments, the embodiments of the present application further provide an ionospheric delay monitoring method. The ionospheric delay monitoring method provided in the embodiments of the present application can also determine the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station through three-way pseudo-range measurement values. The ionospheric delay monitoring method can be applied to the ionospheric delay monitoring system described in any of the above embodiments, and the ionospheric delay monitoring method can be executed by the monitoring station. The following is an exemplary description of the ionospheric delay monitoring method by taking the monitoring station executing the method as an example.

[0065] It should be noted that, because the pseudo-range measurement equipment is set with a zero baseline, the satellite-ground space distances of the three pseudo-range measurement signals are exactly the same, so there is equation (11):

[0066] R true,z1 (n) = R true,z2 (n) = R true,z3 (n)(11);

[0067] In addition, because the pseudo-range measurement equipment has a zero baseline setting, the pseudo-range measurement signals pass through exactly the same atmospheric layer, so the tropospheric delays they are subjected to are exactly the same, and the ionospheric delays are different due to different carrier frequencies. That is, the tropospheric delays of the three pseudo-range measurement signals are also the same, so there is equation (12):

[0068] T duiliu,z1 (n) = T duiliu,z2 (n) = T duiliu,z3 (n)(12);

[0069] When there are x pseudo-range measurement signals, the x pseudo-range measurement signals experience the same spatial distance and the same tropospheric delay.

[0070] It should also be noted that, in this embodiment, the satellite-to-ground space distance, tropospheric delay, and ionospheric delay are all unknown quantities. When calculating the total number of ionospheric electrons on the ranging signal path, the satellite-to-ground space distance and the tropospheric delay are equal and cancel each other out.

[0071] When the satellite broadcasts a pseudorange signal, the obtained pseudorange measurement value has the same Sagnac effect delay and the relativistic effect delay of the satellite clock.

[0072] The following is a detailed introduction to the ionospheric delay monitoring method provided by this application.

[0073] Figure 5 FIG. 1 is a flow chart of an ionospheric delay monitoring method according to an embodiment of the present application, wherein the method is executed by a monitoring station, such as Figure 5 As shown, the ionospheric delay monitoring method may also include the following steps:

[0074] Step 10: Obtain x pseudo-range measurement signals broadcast by the satellite, where x is a positive integer greater than or equal to 3;

[0075] Step 20: synchronously measure the pseudo-range measurement signals to obtain x pseudo-range measurement values, and select y pseudo-range measurement values ​​from the x pseudo-range measurement values; or, select y pseudo-range measurement signals from the x pseudo-range measurement signals for synchronous measurement to obtain y pseudo-range measurement values;

[0076] Step 30: using pseudo-range measurement expressions to represent each of the pseudo-range measurement values;

[0077] Step 40: Divide the y pseudo-range measurement values ​​into two groups, the first group includes m pseudo-range measurement values, and the second group includes h pseudo-range measurement values, wherein 3≤y≤x, m+h=y, m+h=y, m, h are both greater than or equal to 1, and y, m, h are all positive integers;

[0078] Step 50: averaging the two groups of pseudorange measurement values ​​represented by the pseudorange measurement expressions to obtain a first corrected average pseudorange measurement value and a second corrected average pseudorange measurement value;

[0079] Step 60: Determine the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station based on the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value.

[0080] The method for calculating the total number of ionospheric electrons provided by the present application has x pseudorange measurement values, and y pseudorange measurement values ​​are selected from all x pseudorange measurement values, wherein the minimum value of y is 3 and the maximum value does not exceed x, and then the selected y pseudorange measurement values ​​are divided into two groups, one of which has m pseudorange measurement values ​​and the other has h pseudorange measurement values, y=m+h. Each group of pseudorange measurement values ​​is first averaged to obtain a corrected average pseudorange measurement value, and the two corrected average pseudorange measurement values ​​are then subtracted to calculate the total number of ionospheric electrons.

[0081] In order to illustrate the use of this method, here only x=3, y=3, m=2, h=1 is used as an example for exemplary description, that is, there are two corrected average pseudo-range measurement values, the first group first averages the two pseudo-range measurement values, and the second group has only one pseudo-range measurement value, which is also averaged. Then the total number of ionospheric electrons is calculated based on the two corrected average pseudo-range measurement values.

[0082] Correspondingly, in step 10, x=3, and the three pseudorange measurement signals can be recorded as a first pseudorange measurement signal, a second pseudorange measurement signal and a third pseudorange measurement signal, wherein the carrier frequencies of the first pseudorange measurement signal, the second pseudorange measurement signal and the third pseudorange measurement signal are different.

[0083] Step 20 is to synchronously measure the three pseudo-range measurement signals to obtain a first pseudo-range measurement value, a second pseudo-range measurement value and a third pseudo-range measurement value.

[0084] Step 30 is to use the first pseudorange measurement expression to represent the first pseudorange measurement value, use the second pseudorange measurement expression to represent the second pseudorange measurement value, and use the third pseudorange measurement expression to represent the third pseudorange measurement value.

[0085] In an exemplary embodiment, the monitoring station can obtain the formula expression of the first pseudorange measurement value, the second pseudorange measurement value, and the third pseudorange measurement value of the specific embodiment according to the pseudorange measurement value numbered i among the y pseudorange measurement values ​​shown in formula (1), where i is 1, 2, and 3 respectively.

[0086] ρ zi (n) = R true,zi (n)+I zi (n)+T duiliu,zi (n)+c·(δt z (n)-δt s (n))+sagnac zz (n)+Re s (n)+X zi (n)(1);

[0087] The monitoring station may use the first pseudorange measurement expression shown in the following formula (1-1) to represent the first pseudorange measurement value:

[0088] ρ z1 (n) = R true,z1 (n)+I z1 (n)+T duiliu,z1 (n)+c·(δt z (n)-δt s (n))+sagnac zz (n)+Re s (n)+X z1 (n)(1-1);

[0089] Furthermore, the second pseudorange measurement value is represented by the second pseudorange measurement expression shown in the following formula (1-2):

[0090] ρ z2 (n) = R true,z2 (n)+I z2 (n)+T duiliu,z2 (n)+c·(δt z (n)-δt s (n))+sagnac zz (n)+Re s (n)+X z2 (n)(1-2);

[0091] And, the third pseudorange measurement value is represented by the third pseudorange measurement expression shown in the following formula (1-3):

[0092] ρ z3 (n) = R true,z3 (n)+I z3 (n)+T duiliu,z3 (n)+c·(δt z (n)-δt s (n))+sagnac zz (n)+Re s (n)+X z3 (n)(1-3);

[0093] In some embodiments, after step 30, the ionospheric delay monitoring method may further include the following steps: using a pseudorange smoothing algorithm to perform pseudorange smoothing correction on the first pseudorange measurement value, the second pseudorange measurement value, and the third pseudorange measurement value, so as to reduce the random error of the pseudorange measurement value, which is conducive to improving the accuracy of the final determined total number of ionospheric electrons, thereby improving the accuracy of the ionospheric delay between the satellite and the monitoring station. The specific content of the pseudorange smoothing algorithm is not repeated here.

[0094] As described above, the first pseudorange measurement signal, the second pseudorange measurement signal and the third pseudorange measurement signal include the same satellite-to-ground space distance delay and tropospheric delay. Therefore, in step 60, the monitoring station uses three pseudorange measurement values ​​to eliminate the same error terms and ultimately determine the total number of ionospheric electrons between the monitoring station and the satellite.

[0095] Exemplarily, in step 40, all three pseudorange measurement values ​​are selected, x=y=3, and the three pseudorange measurement values ​​are divided into two groups, the first group may include the first pseudorange measurement value and the second pseudorange measurement value, and the second group may include the third pseudorange measurement value.

[0096] Accordingly, step 50 is:

[0097] Step 51: Determine a first corrected average pseudorange measurement value represented by a first corrected average pseudorange measurement expression by using a first pseudorange measurement value represented by a first pseudorange measurement expression and a second pseudorange measurement value represented by a second pseudorange measurement expression.

[0098] Step 52: Determine the pseudorange measurement difference using the first corrected average pseudorange measurement value represented by the first corrected average pseudorange measurement expression and the second corrected average pseudorange measurement value represented by the second corrected average pseudorange measurement expression.

[0099] In step 51, the first group has two pseudorange measurement values, which are averaged to obtain a first corrected average pseudorange measurement value. Specifically, the monitoring station calculates the first average pseudorange value according to formula (2).

[0100]

[0101] At this time, m=2, k=1,2.

[0102] The monitoring station averages the first pseudorange measurement value represented by the first pseudorange measurement expression shown in formula (1-1) and the second pseudorange measurement value represented by the second pseudorange measurement expression shown in formula (1-2) to obtain the first corrected average pseudorange measurement value represented by the first corrected average pseudorange measurement expression shown in formula (2-1):

[0103]

[0104] In step 52, the second group has one pseudorange measurement value, which is averaged to obtain a second corrected average pseudorange measurement value. Specifically, the monitoring station calculates the second corrected average pseudorange measurement value according to formula (3).

[0105]

[0106] At this time, h=1, y=3, j=3.

[0107] The second group has only one pseudorange measurement value, which is the third pseudorange measurement value. The second corrected average pseudorange measurement value is obtained by averaging. The second corrected average pseudorange measurement value is expressed by formula (3-1).

[0108]

[0109] In an exemplary embodiment, step 60 may specifically include the following steps:

[0110] S61: Determine a pseudorange measurement difference using the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value;

[0111] S62: Determine the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station based on the pseudorange ranging difference.

[0112] Specifically, after obtaining the first corrected average pseudorange measurement value, the monitoring station further performs a difference calculation on the first corrected average pseudorange measurement value shown in formula (2-1) and the second corrected average pseudorange measurement value shown in formula (3-1) according to formula (5) for calculating the pseudorange difference value, and simultaneously uses the pseudorange measurement equipment shown in formulas (11) and (12) to set a zero baseline relationship, and obtains the pseudorange measurement difference value shown in the following formula (5-1):

[0113]

[0114] Then, the monitoring station can determine the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station as shown in the following formula (6-1) based on the carrier frequency of each signal in the pseudo-range ranging signal and the preset ionospheric delay coefficient and formula (6) using formula (5-1):

[0115]

[0116] In some embodiments, the value of the ionospheric delay coefficient may be 40.309. In other embodiments, the ionospheric delay coefficient may also be 40.28 or 40.30. In the future, there may be other more precise ionospheric delay coefficients, all of which fall within the scope of protection of this application.

[0117] It is worth mentioning that the Beidou satellite navigation system, GPS satellite navigation system, Galileo satellite navigation system and Glonass satellite navigation system all broadcast triple-frequency pseudo-range measurement signals. Therefore, the above systems can all use the method of total ionospheric electron number provided in the embodiment of the present application to calculate the total ionospheric electron number.

[0118] It is worth noting that the above embodiment only uses three pseudo-range measurement signals as an example to illustrate the method of the present application. When the number of pseudo-range measurement signals x=2, two pseudo-range measurement values ​​are obtained. At this time, y pseudo-range measurement values ​​are still selected, y=x=2, and the y pseudo-range measurement values ​​are divided into two groups, each group has only one pseudo-range measurement value, and each group averages the pseudo-range measurement values ​​in the group. At this time, because each group has only one pseudo-range measurement value, the first corrected average pseudo-range measurement value and the second corrected average pseudo-range measurement value are respectively equal to the two pseudo-range measurement values ​​measured minus their respective hardware device delays. The first corrected average pseudo-range measurement value and the second corrected average pseudo-range measurement value are used to make a difference, and then the total number of ionospheric electrons is calculated. At this time, it is completely consistent with the existing method of directly calculating the total number of ionospheric electrons using two pseudo-range measurement values, that is, the method of the present application degenerates into the known method of calculating the total number of ionospheric electrons using two pseudo-range measurement values. Therefore, the method provided by the present application can also meet the situation of x=2, and the method provided by the present application is more general.

[0119] In this embodiment, after the monitoring station determines the total number of electrons in the ionosphere, the monitoring station can exchange data with the central station based on the communication link, so that the central station can obtain the total number of electrons in the ionosphere of each monitoring station. The central station can improve satellite positioning, navigation accuracy, etc. by summarizing the total number of electrons in the ionosphere of each monitoring station and publishing it. The central station obtains the total number of electrons in the ionosphere determined by the monitoring station based on the data interaction result, and the communication link includes a forward communication link and a return communication link.

[0120] In some embodiments, after determining the total number of ionospheric electrons on the ranging signal path between the monitoring station and the satellite, the method further includes: performing data exchange with a central station based on a communication link, wherein the central station obtains the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station based on the data exchange result, and the communication link includes a forward communication link and a return communication link.

[0121] In summary, it can be seen that the ionospheric delay monitoring method provided in the embodiment of the present application fully utilizes the information of at least three pseudo-range measurement values, and the total number of ionospheric electrons can be accurately calculated using at least three pseudo-range measurement values. The monitoring station can obtain the pseudo-range measurement signal at any time and calculate the real-time total number of ionospheric electrons based on the above method, which has the advantages of strong real-time performance and accurate monitoring results.

[0122] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An ionospheric delay monitoring system, characterized in that: Satellites and monitoring stations including communications links; The satellite is used to send at least three pseudo-range measurement signals to the monitoring station; The monitoring station is used to receive and synchronously measure each of the pseudo-range ranging signals to obtain a plurality of pseudo-range ranging values, and determine the total number of ionospheric electrons on the ranging signal path between itself and the satellite based on each of the pseudo-range ranging values.

2. The ionospheric delay monitoring system according to claim 1, characterized in that: The carrier frequencies of at least three of the plurality of pseudorange measurement signals are different from each other.

3. The ionospheric delay monitoring system according to claim 1, characterized in that: The carrier frequency of at least one pseudorange measurement signal among the plurality of pseudorange measurement signals is frequency-hopped according to a preset frequency-hopping pattern on the time axis.

4. The ionospheric delay monitoring system according to claim 1, characterized in that: The satellite includes satellite time and frequency equipment and pseudo-range generating equipment; the monitoring station includes monitoring time and frequency equipment, pseudo-range measuring equipment and processing equipment; The satellite time and frequency device is used to provide a time and frequency signal to the pseudorange generating device; The pseudorange generating device is used to generate and broadcast the at least three pseudorange ranging signals, wherein the pseudorange ranging signals are spread spectrum signals; Wherein, the satellite time and frequency device and the pseudorange generating device are integrated or separately arranged; The monitoring time-frequency device is at least used to provide a time-frequency signal to the pseudo-range measuring device; The pseudo-range measuring device is used to receive each of the pseudo-range measuring signals, and synchronously measure each of the pseudo-range measuring signals to obtain a plurality of pseudo-range measuring values; The processing device is in communication connection with the pseudo-range measuring device, and the processing device is used to obtain each of the pseudo-range measuring values, and determine the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station based on each of the pseudo-range measuring values; The time-frequency monitoring device, the pseudo-range measuring device and the processing device are separately or integratedly arranged.

5. The ionospheric delay monitoring system according to claim 4, characterized in that: The pseudo-range generating device has a transmission delay, and the pseudo-range measuring device has a reception delay; The transmission delay of the pseudorange generating device is transmitted through a pseudorange measuring signal, or the transmission delay of the pseudorange generating device and the receiving delay of the pseudorange measuring device are preset in the processing device.

6. The ionospheric delay monitoring system according to claim 1, characterized in that: The monitoring station synchronously measures each of the pseudo-range measurement signals at a preset time interval to obtain a plurality of the pseudo-range measurement values; the monitoring station includes one or more of the pseudo-range measurement devices, and when there are multiple pseudo-range measurement devices, a zero baseline is set for the multiple pseudo-range measurement devices.

7. The ionospheric delay monitoring system according to claim 1, characterized in that: The system further comprises: The central station is connected to the monitoring station for communication. The central station obtains the monitoring parameters of the monitoring station based on the communication result with the monitoring station.

8. The ionospheric delay monitoring system according to claim 7, characterized in that: The central station is directly connected to the monitoring station for communication; or, the central station is connected to the monitoring station for communication via the satellite; When the central station is in communication connection with the monitoring station via the satellite, there is a main feeder link between the central station and the satellite, and there is a slave feeder link between the monitoring station and the satellite; The main feeder link includes a main feeder link up signal and a main feeder link down signal, the slave feeder link includes a slave feeder link up signal and a slave feeder link down signal, the main feeder link up signal and the slave feeder link down signal constitute a forward communication link, and the slave feeder link up signal and the main feeder link down signal constitute a return communication link; The monitoring station and the central station are connected by satellite communication via the forward communication link and the return communication link.

9. A method for monitoring ionospheric delay, characterized in that: Applied to the ionospheric delay monitoring system according to any one of claims 1 to 8, the method is performed by a monitoring station, and the method comprises: Acquire x pseudorange measurement signals broadcast by the satellite, where x is a positive integer greater than or equal to 3; Synchronously measuring each of the pseudorange ranging signals to obtain x pseudorange ranging values, and selecting y pseudorange ranging values ​​from the x pseudorange ranging values; or, selecting y from the x pseudorange ranging signals for synchronous measurement to obtain y pseudorange ranging values; Using pseudorange measurement expressions to represent each of the pseudorange measurement values; Divide the y pseudorange measurement values ​​into two groups, the first group includes m pseudorange measurement values, and the second group includes h pseudorange measurement values, wherein 3≤y≤x, m+h=y, m and h are both greater than or equal to 1, and y, m, and h are all positive integers; The two groups of pseudo-range measurement values ​​represented by each pseudo-range measurement expression are respectively averaged to obtain a first corrected average pseudo-range measurement value and a second corrected average pseudo-range measurement value; The total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station is determined based on the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value.

10. The ionospheric delay monitoring method according to claim 9, characterized in that: The pseudorange measurement expressions are used to represent the pseudorange measurement values ​​respectively, including: The pseudorange measurement value numbered i is represented by the pseudorange measurement expression shown in the following formula (1): zi (n) = R true,zi (n)+I zi (n)+T duiliu,zi (n)+c·(δt z (n)-δt s (n))+sagnac zz (n)+Re s (n)+X zi (n) (1); Wherein, i=1, 2, ..., y, i is a positive integer; Where: zi (n) represents the pseudo-range measurement value numbered i at the nth moment, in meters; R true,zi (n) represents the real space distance traversed by the pseudo-range measurement signal numbered i at the nth moment, in meters; I zi (n) represents the ionospheric delay of the pseudo-range signal numbered i at the nth time, in meters; T duiliu,zi (n) represents the tropospheric delay of the pseudo-range measurement signal numbered i at the nth moment, in meters; c represents the speed of light, in meters per second; δt s (n) represents the clock difference between the satellite and the system time at the nth moment, in seconds; δt z (n) represents the clock difference of the monitoring station at the nth moment relative to the system time, in seconds; sagnac zz (n) represents the Sagnac effect delay of the pseudo-range measurement signal at the nth moment, in meters; Re s (n) represents the relativistic delay of the satellite clock at the nth moment, in meters; X zi (n) represents the hardware device delay of the pseudorange ranging signal numbered i at the nth moment, in meters. The hardware device delay of the pseudorange ranging signal includes the satellite's transmission delay for the pseudorange ranging signal numbered i and the monitoring station's reception delay for the pseudorange ranging signal numbered i.

11. The ionospheric delay monitoring method according to claim 9, characterized in that: The determining, based on the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value, the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station comprises: Determine a pseudorange measurement difference value using the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value; The total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station is determined based on the pseudorange measurement difference.

12. The ionospheric delay monitoring method according to claim 11, characterized in that: The determining, based on the pseudorange measurement difference, the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station comprises: Based on the carrier frequency of each signal in the pseudorange ranging signal and the preset ionospheric delay coefficient, and the pseudorange ranging difference, the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station is determined as shown in the following formula (6): Where: m represents the number of the first set of pseudo-range measurement values; k represents the number of the first set of pseudo-range measurement values; h represents the number of the second set of pseudo-range measurement values; j represents the number of the second set of pseudo-range measurement values; y represents the total number of selected pseudo-range measurement values; dρ(n) represents the pseudo-range measurement difference, in meters; Q ion represents the ionospheric delay coefficient; TEC(n) represents the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station at the nth moment, unit: electron / square meter; f zk (n) represents the carrier frequency of the pseudo-range measurement signal numbered k at the nth time, in Hertz; f zj (n) represents the carrier frequency of the pseudo-range measurement signal numbered j at the nth moment, in Hertz.

13. The ionospheric delay monitoring method according to claim 12, characterized in that: The method of respectively calculating the average of two groups of pseudorange measurement values ​​represented by each pseudorange measurement expression to obtain a first corrected average pseudorange measurement value and a second corrected average pseudorange measurement value comprises: The first group of m pseudorange measurement values ​​represented by the pseudorange measurement expression are averaged to obtain the first corrected average pseudorange measurement value as shown in formula (2): Wherein, k is a positive integer from 1 to m; The second group of h pseudorange measurement values ​​represented by the pseudorange measurement expression are averaged to obtain the second corrected average pseudorange measurement value as shown in formula (3): Wherein, j is a positive integer from m+1 to y; The determining of the pseudorange measurement difference by using the first corrected average pseudorange measurement value and the second corrected average pseudorange measurement value comprises: According to the first corrected average pseudorange measurement value shown in formula (2) and the second corrected average pseudorange measurement value shown in formula (3), the pseudorange measurement difference value shown in the following formula (5) is determined: Where: m represents the number of the first group of pseudo-range measurement values; k represents the number of the first group of pseudo-range measurement values; h represents the number of the second group of pseudo-range measurement values; j represents the number of the second group of pseudo-range measurement values; y represents the total number of selected pseudo-range measurement values; dρ(n) represents the pseudo-range measurement difference, in meters; ρ 1,mean (n) represents the first corrected average pseudorange measurement value, unit: meter; ρ 2,mean (n) represents the second corrected average pseudorange measurement value, unit: meter; ρ zk (n),ρ zj (n) represents the pseudo-range measurement value numbered k or j at the nth moment, in meters; R true,zk (n), R true,zj (n) represents the real space distance that the pseudo-range measurement signals numbered k and j have traveled at the nth moment, in meters; I zk (n), I zj (n) represents the ionospheric delay of the pseudo-range measurement signal numbered k, j at the nth moment, in meters; T duiliu,zk (n), T duiliu,zj (n) represents the tropospheric delay of the pseudo-range measurement signal numbered k, j at the nth moment, in meters; X zk (n), X zj (n) represents the hardware device delay of the pseudorange ranging signals numbered k and j at the nth moment, in meters. The hardware device delay of the pseudorange ranging signal includes the transmission delay of the satellite for the pseudorange ranging signals numbered k and j, and the reception delay of the monitoring station for the pseudorange ranging signals numbered k and j.

14. The ionospheric delay monitoring method according to claim 9, characterized in that: After determining the total number of ionospheric electrons on the ranging signal path between the monitoring station and the satellite, the method further includes: Data is exchanged with a central station based on a communication link, wherein the central station obtains the total number of ionospheric electrons on the ranging signal path between the satellite and the monitoring station based on the data interaction result, and the communication link includes a forward communication link and a return communication link.

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