A method for measuring ionospheric vertical electron density

Abstract

The present invention discloses a method for measuring the vertical electron density of the ionosphere. The first step is to output n T values ​​of the meteor trail communication device within a time period T. p (t). In “T p (t) and V P (t) According to each T in the corresponding table p (t) Numerical query V P (t) value; the duration T of measuring the received signal strength P of the meteor trail p (t), and the vertical electron density of the ionosphere outside the meteor trail area, that is, the vertical electron density of the background ionosphere of the meteor trail is called V(t); the average value V of the vertical electron density of the background ionosphere in the meteor trail area within the period T is obtained; dV(t) and f(T P (t)); f(T P (t)) is the average of V(t) in the T period as the background ionosphere vertical electron density V in the area during the period. Ionosphere monitoring based on GNSS signals uses an inversion algorithm to calculate the electron density of each layer of the ionosphere. The obtained meteor trail background ionosphere vertical electron density V is more accurate, and the revelation of the ionosphere activity law in the area is more real and powerful. It can be widely used in the fields of improving satellite navigation accuracy, improving satellite communication performance and fast frequency selection of shortwave communications.

Description

Technical Field

[0001] The invention belongs to the field of communications, and in particular relates to a method for predicting the vertical electron density of the ionosphere. Background Art

[0002] When a meteor encounters the Earth, it breaks into the Earth's atmosphere, and its speed relative to the Earth reaches 12 to 72 kilometers per second. The high-speed meteor rubs violently against the air in the atmosphere. As the meteor penetrates into the dense area of ​​the atmosphere (120 to 80 kilometers above sea level), the friction becomes more intense, and substances such as iron and calcium begin to melt and evaporate. The atoms of the substance gain a very high thermal motion speed, which arouses the ionization of the surrounding atmosphere. As the meteor moves, a cylindrical ionized gas column is formed at the tail of the meteor, which is called a "meteor trail." After the meteor trail is formed, the initial radius is only a few centimeters, and then the volume of the meteor trail expands rapidly. During the diffusion process, the electron density in the meteor trail decreases until the meteor trail disappears. Generally, the diffusion process lasts from a few tenths of a second to a few seconds. For huge meteor trails, it lasts for several minutes. The diameter of the ionized gas column is 5 kilometers, and the length of the meteor trail is 30 kilometers. Huge meteors can be seen with the naked eye. A boundary is formed between the ionized gas column and the ionosphere.

[0003] By measuring the pseudorange and carrier phase data of GNSS signals at different frequencies, we can analyze and obtain parameters such as the total electron concentration (TEC) of the ionospheric layer at the ionosphere puncture point under different satellite signals, thereby giving the temporal and spatial changes of relevant ionosphere parameters, which is of great significance in ionospheric scientific research and engineering applications, such as satellite navigation, satellite communications and shortwave communications. This technology cannot accurately detect the ionosphere in layers, introduces the limitations of the thin-layer hypothetical ionosphere tomography model, and cannot overcome the limitations of empirical models and traditional ground detection methods. At present, it is only suitable for monitoring the vertical distribution and disturbance state of the large-scale ionospheric electron density of nearly 1,000 kilometers, but cannot directly, real-time and accurately measure the small-scale ionospheric electron density of tens of kilometers. Summary of the invention

[0004] The purpose of the present invention is to provide a method for measuring the vertical electron density of the ionosphere, which measures the vertical electron density of the ionosphere in a small-scale area in the ionosphere through the boundary formed by the meteor trail.

[0005] The object of the present invention is achieved by the following technical means: a method for predicting the vertical electron density of the ionosphere,

[0006] Get the n V output by the meteor trail communication device within the time period T P (t) and T P (t), where V P(t) is the vertical electron density of the ionosphere in the set scale area at the set height above the midpoint of the line connecting the master and slave stations of the meteor trail communication antenna; T P (t) is the duration of the received signal strength P of the meteor trail;

[0007] Obtain the background ionospheric vertical electron density V1(t) in the meteor trail region within the time period T, and obtain the mean value V1;

[0008] According to the physical characteristics of the ionosphere, we can get T P The fitting function of (t), that is, f(T P (t));

[0009] Predict the vertical electron density V(t) of the background ionosphere of the meteor trail at time t in the next T period, V(t) = V P (t)-f(T P (t));

[0010] The average value of V(t) in the T period is the background ionospheric vertical electron density V in the area in the next T period;

[0011] The background ionospheric vertical electron density V is used in satellite navigation, satellite communication and shortwave communication, so as to enhance the accuracy of satellite navigation, improve the performance of satellite communication and achieve rapid frequency selection of shortwave communication.

[0012] The duration T of the received signal strength P of the meteor trail p (t) Measured by meteor trail communication equipment.

[0013] The vertical electron density V1(t) of the background ionosphere in the meteor trail region during period T is measured by GNSS equipment.

[0014] The value of T is n T P The maximum value in (t).

[0015] The f(T P (t)) = k1T P (t)+k0.

[0016] The f(T P (t)) = k2(T P (t)) 2 +k1T P (t)+k0.

[0017] When f(T P When f(T)) is a nonlinear function, P (t)) is linearized to obtain dV(t)-dV(t-1)=f'(T P (t)) = 2k2T P(t)+k1, k is obtained by linear regression i , i=1, 2, k0=dV(t)-k2(T P (t)) 2 +k1T P (t), dV(T) = V P (t)-V1.

[0018] The coefficient k is determined by calculating the linear regression method from n dV(t) in the T period. i ,i=0,1,…;dV(T)=V P (t)-V1.

[0019] The beneficial effects of the present invention are as follows: the ionosphere monitoring based on GNSS signals uses an inversion algorithm to calculate the electron density of each layer of the ionosphere, which introduces the limitations of the thin-layer hypothetical ionosphere tomography model, while the ionization density obtained by meteor trail communication comes from a small-scale area of ​​30 km above the midpoint of the antenna line between the transceiver stations at an altitude of 100 km above the ground, so data acquisition is more direct. The obtained meteor trail background ionosphere vertical electron density V is more accurate, and the revelation of the ionosphere activity law in the region is more real and powerful, which can be widely used in the fields of improving satellite navigation accuracy, improving satellite communication performance and fast frequency selection of shortwave communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the meteor trail channel propagation;

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0022] [Example 1]

[0023] like Figure 1 As shown in Figure 1, a method for predicting the vertical electron density of the ionosphere is

[0024] Get the n V output by the meteor trail communication device within the time period T P (t) and T P (t), where V P (t) is the vertical electron density of the ionosphere in the set scale area at the set height above the midpoint of the line connecting the master and slave stations of the meteor trail communication antenna; T P (t) is the duration of the received signal strength P of the meteor trail;

[0025] Specific V P(t) is the vertical electron density of the ionosphere at an altitude of 100 km above the ground and in a small-scale area of ​​30 km above the midpoint of the line connecting the main and slave stations of the meteor trail communication antenna. The altitude and size are changed according to the position of the ionosphere used for communication.

[0026] During the period T, the meteor trail communication device outputs n T P (t), in “V P (t) and T P (t) According to each T P (t) Numerical query V P The value of (t).

[0027] Through the long-term observation records of the meteor trail observatory, V P (t) and T P (t) corresponding table, and then according to the recorded T P (t) value, query to get V P (t)

[0028] Obtain the vertical electron density V1(t) of the background ionosphere in the meteor trail region within the time period T, and obtain the mean value V1; Figure 1 As shown, V1(t) is obtained according to the GPS receiver and GPS.

[0029] According to the physical characteristics of the ionosphere, we can get T P The fitting function of (t), that is, f(T P (t));

[0030] Where f(T P (t)) According to the physical characteristics of the ionosphere, there are many forms of fitting functions, which vary with the location of the observation station, the time of observation, and the physical parameters of the meteor trail, but T P The value of (t) is V P (t)-V(t) is an increasing function.

[0031] According to practical observation experience, f(T P (t)) can be in polynomial form and can be T P (t) first degree polynomial, second degree polynomial

[0032] f(T P (t)) can also use other function forms, but must satisfy T P The value of (t) is V P (t)-V(t) is an increasing function.

[0033] Predict the vertical electron density V(t) of the background ionosphere of the meteor trail at time t in the next T period, V(t) = V P (t)-f(TP (t));

[0034] The average value of V(t) in the T period is the background ionospheric vertical electron density V in the area in the next T period;

[0035] The background ionospheric vertical electron density V is used in satellite navigation, satellite communication and shortwave communication, so as to enhance the accuracy of satellite navigation, improve the performance of satellite communication and achieve rapid frequency selection of shortwave communication.

[0036] The duration T of the received signal strength P of the meteor trail p (t) is measured by meteor trail communication equipment. p (t) Figure 1 The meteor trail communication antenna is measured by the master and slave stations.

[0037] The vertical electron density V1(t) of the background ionosphere in the meteor trail region during the period T is measured by GNSS equipment. Figure 1 GPS receiver and GPS satellites in the.

[0038] The cylindrical reflector formed by the meteor trail and the observation data V P (t) and T P (t) is used to calculate the background ionosphere vertical electron density V in the area during the period T, and a more accurate background ionosphere vertical electron density V is obtained, thereby improving satellite navigation accuracy, improving satellite communication performance, and enabling shortwave communication to quickly select frequencies.

[0039] The value of T is n T P The maximum value in (t).

[0040] The f(T P (t)) = k1T P (t)+k0.

[0041] The f(T P (t)) = k2(T P (t)) 2 +k1T P (t)+k0.

[0042] When f(T P When f(T)) is a nonlinear function, P (t)) is linearized to obtain dV(t)-dV(t-1)=f'(T P (t)) = 2k2T P (t)+k1, k is obtained by linear regression i , i=1, 2, k0=dV(t)-k2(T P (t))2 +k1T P (t), dV(T) = V P (t)-V1.

[0043] The coefficient k is determined by calculating the linear regression method from n dV(t) in the T period. i ,i=0,1,…;dV(T)=V P (t)-V1.

[0044] Finally, the background ionospheric vertical electron density V is used in satellite navigation, satellite communication and shortwave communication.

[0045] In the existing technology, the obtained values ​​of the background ionosphere vertical electron density V within a large-scale range of thousands of kilometers are the same. There is a gap between the background ionosphere vertical electron density V at different altitudes, which leads to a large error between the obtained value and the actual value. By utilizing the meteor trail phenomenon within a small-scale range of tens of kilometers, a more accurate background ionosphere vertical electron density V within this scale range can be obtained, thereby achieving the purpose of improving satellite navigation accuracy, improving satellite communication performance, and rapid frequency selection of shortwave communications.

Claims

1. A method for predicting the vertical electron density of the ionosphere, Features: Get the n V output by the meteor trail communication device within the time period T P (t) and T P (t), where V P (t) is the vertical electron density of the ionosphere in the set scale area at the set height above the midpoint of the line connecting the master and slave stations of the meteor trail communication antenna; T P (t) is the duration of the received signal strength P of the meteor trail; Get the vertical electron density V of the background ionosphere in the meteor trail area during the period T 1 (t), and get the mean value V 1 ; According to the physical characteristics of the ionosphere, we can get T P The fitting function of (t), that is, f(T P (t)); Predict the vertical electron density V(t) of the background ionosphere of the meteor trail at time t in the next T period, V(t) = V P (t)-f(T P (t)); The average value of V(t) in the T period is the background ionospheric vertical electron density V in the area in the next T period; The background ionospheric vertical electron density V is used in satellite navigation, satellite communication and shortwave communication, so as to enhance the accuracy of satellite navigation, improve the performance of satellite communication and achieve rapid frequency selection of shortwave communication.

2. A method for predicting ionospheric vertical electron density according to claim 1, Features: The duration T of the received signal strength P of the meteor trail p (t) Measured by meteor trail communication equipment.

3. The method for predicting the vertical electron density of the ionosphere according to claim 1, Features: The vertical electron density V of the background ionosphere in the meteor trail region during the period T 1 (t) Measured by GNSS equipment.

4. The method for predicting the vertical electron density of the ionosphere according to claim 1, Features: The value of T is n T P The maximum value in (t).

5. The method for predicting the vertical electron density of the ionosphere according to claim 1, Features: The f(T P (t)) = k 1 T P (t)+k 0 .

6. The method for predicting the vertical electron density of the ionosphere according to claim 1, Features: The f(T P (t)) = k 2 (T P (t)) 2 +k 1 T P (t)+k 0 .

7. A method for predicting ionospheric vertical electron density according to claim 5 or 6, Features: When f(T P When f(T)) is a nonlinear function, P (t)) is linearized to obtain dV(t)-dV(t-1)=f'(T P (t))=2k 2 T P (t)+k 1 , we get k by linear regression i , i=1,2,k 0 =dV(t)-k 2 (T P (t)) 2 +k 1 T P (t), dV(T) = V P (t)-V 1 .

8. A method for predicting ionospheric vertical electron density according to claim 5 or 6, Features: The coefficient k is determined by calculating the linear regression method from n dV(t) in the T period. i ,i=0,1,…;dV(T)=V P (t)-V 1 .

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