A deception jamming detection method based on pure inertial speed assistance

Abstract

The application provides a kind of fraud interference detection method based on pure inertial speed auxiliary, utilizes the inertial auxiliary information that inertial measurement device is output in navigation stage, by Doppler consistency detection to each satellite, removes fraud signal, then carries out the position speed solution of satellite navigation positioning device, afterwards, the accuracy detection of solution result is carried out, the reliability of positioning is improved.The method can quickly detect fraud signal in the presence of fraud interference, and has certain fraud signal removal capability, and the algorithm is simple to apply, without complex or large amount of calculation formula, real-time and operation amount can be guaranteed on the algorithm programming realization of DSP or FPGA hardware platform, that is, easy to engineering implementation.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of satellite navigation technology, and particularly relates to a spoofing interference detection method based on pure inertial speed assistance. BACKGROUND

[0002] In the use environment of military satellite navigation positioning devices, the situation of human-made spoofing interference is often faced. Spoofing interference is to broadcast signals same as or similar to real satellite navigation signals, so that the satellite navigation positioning device receives and uses the spoofing signals, resulting in incorrect positioning, and achieving the purpose of spoofing interference.

[0003] At present, the satellite navigation positioning device cannot be correctly positioned when encountering spoofing interference. SUMMARY

[0004] The present application provides a spoofing interference detection method based on pure inertial speed assistance, which can solve the technical problem that the satellite navigation positioning device cannot be correctly positioned when encountering spoofing interference.

[0005] The present application provides a spoofing interference detection method based on pure inertial speed assistance, which comprises:

[0006] S10, the satellite navigation positioning device captures the satellite navigation signal, and performs bit synchronization and frame synchronization on the tracking satellite based on the satellite navigation signal;

[0007] S20, on the basis of completing the frame synchronization of the satellite navigation positioning device and the tracking satellite, the pseudo-range, the Doppler observation and the ephemeris parameter of each satellite are obtained;

[0008] S30, the transmission time of each satellite is obtained based on the pseudo-range of each satellite, and the position information and the speed information of each satellite are obtained based on the transmission time of each satellite and the ephemeris parameter;

[0009] S40, in the case that the inertial measurement device is in the navigation state, the inertial assistance information output by the inertial measurement device is obtained, and it is judged whether the X, Y and Z direction inertial accelerations in the inertial assistance information are all not greater than the preset acceleration and the pure inertial combined speed in the inertial assistance information is not less than the preset combined speed, if yes, turn to S50, otherwise, turn to S60; wherein the inertial assistance information comprises the X, Y and Z direction inertial accelerations and the X, Y and Z direction inertial speeds in the geocentric rectangular coordinate system;

[0010] S50, taking the speed information output by the inertial measurement device as the speed information of the satellite navigation positioning device, obtaining the satellite Doppler backstepping of each satellite based on the speed information of the satellite navigation positioning device and the speed information of each satellite, eliminating the satellites whose absolute value of the difference between the Doppler observation and the backstepping satellite Doppler is greater than a preset threshold, judging whether the number of eliminated satellites is greater than or equal to three, if yes, there is a spoofing interference, turning to S10, otherwise, turning to S60;

[0011] S60, establishing a satellite navigation positioning device position and speed solving equation based on the position information and pseudo-range of the eliminated satellites, the position information and clock error of the satellite navigation positioning device; linearizing the satellite navigation positioning device position and speed solving equation to obtain a first observation equation about position and a second observation equation about speed;

[0012] S70, performing least squares iteration on the first observation equation to obtain the position information of the satellite navigation positioning device; performing least squares iteration on the second observation equation to obtain the speed information of the satellite navigation positioning device; wherein the speed information of the satellite navigation positioning device includes X, Y, Z direction positioning device speed in the geocentric rectangular coordinate system;

[0013] S80, performing coordinate conversion on the X, Y, Z direction inertial speed in the geocentric rectangular coordinate system to obtain the north, sky, east direction inertial speed in the geodetic coordinate system; performing coordinate conversion on the X, Y, Z direction positioning device speed in the geocentric rectangular coordinate system to obtain the north, sky, east direction positioning device speed in the geodetic coordinate system;

[0014] S90, judging whether the absolute value of the difference between the east direction inertial speed and the east direction positioning device speed is not more than a preset east speed, the absolute value of the difference between the north direction inertial speed and the north direction positioning device speed is not more than a preset north speed, and the absolute value of the difference between the inertial horizontal combined speed of the east direction and the north direction and the positioning device horizontal combined speed of the east direction and the north direction is not more than a preset horizontal combined speed, if yes, there is no spoofing interference, taking the position information and speed information of the satellite navigation positioning device as the positioning result, otherwise, there is a spoofing interference, turning to S10.

[0015] Preferably, in S40, the preset acceleration is set to 30 m / s 2 , and the preset combined speed is set to 100 m / s.

[0016] Preferably, the backstepping satellite Doppler of each satellite is obtained by the following formula:

[0017]

[0018] In the formula, A is the backstepping satellite Doppler, and are the X, Y, Z direction speeds of the Jth satellite respectively, X, Y, Z velocity of the satellite navigation positioning device respectively, X, Y, Z unit vectors of the satellite navigation positioning device pointing to the Jth satellite respectively, t u is the clock drift.

[0019] Preferably, the preset threshold in S50 is set to 25 Hz.

[0020] Preferably, the satellite navigation positioning device position and velocity solving equation is established by the following formula:

[0021]

[0022] In the formula, ρ J is the pseudo-range of the Jth satellite, J = 1, 2,..., n, n is the total number of satellites after rejection, X J , Y J , Z J are X, Y, Z coordinates of the Jth satellite respectively, X U , Y U , Z U are X, Y, Z coordinates of the satellite navigation positioning device respectively, C is the speed of light, t u is the clock error.

[0023] Preferably, the first observation equation about position is obtained by the following formula:

[0024] z1 = Hx1 + ε

[0025] wherein,

[0026] x1 = (X U , Y U , Z U , t u )

[0027]

[0028] In the formula, z1 is the first observation, H is the coefficient matrix, x1 is the first state quantity, ε is the measurement error, X, Y, Z unit vectors of the satellite navigation positioning device pointing to the Jth satellite respectively.

[0029] Preferably, the second observation equation about velocity is obtained by the following formula:

[0030] z2 = Hx2 + ε

[0031] wherein, z2 = B

[0032]

[0033] In the formula, z2 is a second observation, x2 is a second state quantity, and B is a Doppler observation.

[0034] Preferably, in S90, the preset east speed, the preset north speed and the preset horizontal resultant speed are all set to 5 m / s.

[0035] Preferably, the rate at which the inertial measurement device outputs the inertial auxiliary information is not less than the positioning frequency of the satellite navigation positioning device.

[0036] By using the inertial auxiliary information output by the inertial measurement device in the navigation stage, the application detects the Doppler consistency of each satellite, eliminates the spoofing signals, and then performs the position and speed calculation of the satellite navigation positioning device, and then performs the accuracy detection of the calculation result, thereby improving the reliability of the positioning. The method can quickly detect the spoofing signals in the presence of spoofing interference, has a certain spoofing signal elimination capability, and has a simple algorithm without complex or large amount of calculation formula. The real-time performance and the amount of calculation can be guaranteed in the algorithm programming implementation on the DSP or FPGA hardware platform, that is, the engineering implementation is easy. BRIEF DESCRIPTION OF DRAWINGS

[0037] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is apparent that the accompanying drawings described below are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0038] Figure 1 A flowchart of a spoofing interference detection method based on pure inertial speed assistance provided by an embodiment of the application is shown. DETAILED DESCRIPTION

[0039] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0040] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0041] The relative arrangement of parts and steps, numerical expressions, and numerical values set forth in the examples are not intended to limit the scope of the application unless otherwise specifically stated. It is to be understood that the drawings are not necessarily to scale as the dimensions of the parts shown are for the purpose of illustration and description only. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as if the techniques, methods, and apparatus were discussed in detail herein. In all examples shown and discussed herein, any specific values are to be interpreted as illustrative only and not as a limitation. Thus, other examples of example embodiments can have different values. It is noted that like numbers and letters on the figures identify like parts throughout the several figures, and thus, once an item is defined in one figure, it is not necessary to discuss it further in connection with other figures.

[0042] As shown in Figure 1 The present application provides a pure inertial velocity auxiliary-based deception jamming detection method, which comprises:

[0043] S10, a satellite navigation positioning device captures a satellite navigation signal and performs bit synchronization and frame synchronization on a tracking satellite based on the satellite navigation signal;

[0044] S20, based on the frame synchronization of the satellite navigation positioning device and the tracking satellite, pseudo-range, Doppler observation and ephemeris parameters of each satellite are obtained;

[0045] S30, the transmission time of each satellite is obtained based on the pseudo-range of each satellite, and the position information and velocity information of each satellite are obtained based on the transmission time of each satellite and the ephemeris parameters;

[0046] S40, in the case that the inertial measurement device is in a navigation state, inertial auxiliary information output by the inertial measurement device is obtained, it is judged whether the X, Y and Z direction inertial accelerations in the inertial auxiliary information are all not greater than a preset acceleration and the pure inertial combined velocity in the inertial auxiliary information is not less than a preset combined velocity, if yes, go to S50, otherwise, go to S60; wherein the inertial auxiliary information includes X, Y and Z direction inertial accelerations and X, Y and Z direction inertial velocities in the geocentric rectangular coordinate system;

[0047] S50, taking the speed information output by the inertial measurement device as the speed information of the satellite navigation positioning device, obtaining the satellite Doppler backstepping of each satellite based on the speed information of the satellite navigation positioning device and the speed information of each satellite, eliminating the satellite whose absolute value of the difference between the Doppler observation and the backstepping satellite Doppler is greater than a preset threshold, judging whether the number of eliminated satellites is greater than or equal to three, if yes, there is a deception interference, turning to S10, otherwise, turning to S60;

[0048] S60, based on the position information and the pseudo-range of the eliminated satellite and the position information and the clock difference of the satellite navigation positioning device, establishing a satellite navigation positioning device position and speed solving equation; linearizing the satellite navigation positioning device position and speed solving equation to obtain a first observation equation about position and a second observation equation about speed;

[0049] S70, performing least square iteration on the first observation equation to obtain the position information of the satellite navigation positioning device; performing least square iteration on the second observation equation to obtain the speed information of the satellite navigation positioning device; wherein the speed information of the satellite navigation positioning device includes X, Y and Z direction positioning device speed in the geocentric rectangular coordinate system;

[0050] S80, performing coordinate conversion on the X, Y and Z direction inertial speed in the geocentric rectangular coordinate system to obtain the north, sky and east direction inertial speed in the geodetic coordinate system; performing coordinate conversion on the X, Y and Z direction positioning device speed in the geocentric rectangular coordinate system to obtain the north, sky and east direction positioning device speed in the geodetic coordinate system;

[0051] S90, judging whether the absolute value of the difference between the east direction inertial speed and the east direction positioning device speed is not more than a preset east speed, the absolute value of the difference between the north direction inertial speed and the north direction positioning device speed is not more than a preset north speed, and the absolute value of the difference between the inertial horizontal combined speed of the east direction and the north direction and the positioning device horizontal combined speed of the east direction and the north direction is not more than a preset horizontal combined speed, if yes, there is no deception interference, taking the position information and the speed information of the satellite navigation positioning device as the positioning result, otherwise, there is a deception interference, turning to S10.

[0052] The present application utilizes the inertial auxiliary information output by the inertial measurement device in the navigation stage, detects the Doppler consistency of each satellite, eliminates the deception signal, then performs the position and speed solving of the satellite navigation positioning device, and then detects the accuracy of the solving result, thereby improving the reliability of the positioning. The method can quickly detect the deception signal in the presence of deception interference, has a certain deception signal elimination capability, the algorithm is simple to apply, there is no complex or huge calculation formula, and the real-time performance and the calculation amount can be guaranteed in the algorithm programming implementation on the DSP or FPGA hardware platform, that is, easy to implement in engineering.

[0053] In order to have a further understanding of the present application, the following Figure 1 A fraud jamming detection method based on pure inertial velocity assistance is described in detail, which comprises the following steps:

[0054] Step one, satellite acquisition, tracking and synchronization

[0055] The satellite navigation positioning device acquires satellite navigation signals, and performs bit synchronization and frame synchronization on the tracked satellites based on the satellite navigation signals; wherein the bit synchronization is completed before the frame synchronization;

[0056] Step two, observation extraction

[0057] On the basis of completing the frame synchronization of the satellite navigation positioning device and the tracked satellites, the pseudorange, Doppler observation and ephemeris parameters of each satellite after completing the frame synchronization are obtained;

[0058] Step three, satellite position and velocity calculation

[0059] Based on the pseudorange of each satellite, the transmission time of each satellite is obtained, and based on the transmission time and the ephemeris parameters of each satellite, the position information and velocity information of each satellite are obtained according to the satellite position calculation method provided by the satellite navigation interface control file (ICD);

[0060] Step four, fraud jamming detection condition judgment

[0061] In the case that the inertial measurement device is in the navigation state (i.e. the misalignment state), the inertial assistance information output by the inertial measurement device is obtained, and it is judged whether the X, Y and Z direction inertial accelerations in the inertial assistance information are all not greater than 30 m / s 2 and the pure inertial combined velocity in the inertial assistance information is not less than 100 m / s, if yes, go to step five, otherwise, go to step six;

[0062] Wherein, the rate of the inertial assistance information output by the inertial measurement device is not less than the positioning frequency of the satellite navigation positioning device;

[0063] Step five, satellite Doppler consistency detection

[0064] The pure inertial velocity information (X, Y and Z direction inertial velocities) in the inertial assistance information is taken as the three-dimensional velocity of the satellite navigation positioning device, and the satellite Doppler backstepping of each satellite is obtained by the following formula:

[0065]

[0066] Wherein, A is the backstepping satellite Doppler, are the X, Y and Z direction velocities of the Jth satellite, are the X, Y and Z direction velocities of the satellite navigation positioning device, are the unit vectors of the satellite navigation positioning device pointing to the X, Y, Z directions of the Jth satellite, respectively, t u is the clock drift.

[0067] If the number of removed satellites is greater than or equal to three, it is determined that there is a spoofing interference, a warning is sent to the satellite navigation positioning device, and the process goes to step one, otherwise, the process goes to step six.

[0068] If the same satellite exceeds the detection threshold for five times in succession, it is considered that the tracking signal of the satellite is a spoofing signal, the signal is removed from the tracking channel, and other satellite signals are captured.

[0069] Step six, satellite navigation positioning device position and velocity solution

[0070] According to the available satellites removed in step five, a satellite navigation positioning device position and velocity solution equation is established:

[0071]

[0072] In the formula, ρ J is the pseudo-range of the Jth satellite, J = 1, 2,..., n, n is the total number of satellites removed, X J , Y J , Z J are the X, Y, Z coordinates of the Jth satellite, respectively, X U , Y U , Z U are the X, Y, Z coordinates of the satellite navigation positioning device, respectively, C is the speed of light, t u is the clock error.

[0073] The satellite navigation positioning device position and velocity solution equation is linearized to obtain a first observation equation about the position:

[0074] z1 = Hx1 + ε

[0075] In the formula, z1 is an n x 1 vector,

[0076] x1 = (X U , Y U , Z U , t u ) is a 4 x 1 vector,

[0077]

[0078] In the formula, z1 is a first observation, H is a coefficient matrix, x1 is a first state quantity, and ε is a measurement error, X, Y, Z are unit vectors of the satellite navigation positioning device pointing to the Jth satellite in X, Y, Z directions respectively;

[0079] wherein, Similarly, the calculation is ε is an n x 1 measurement error vector, which can include random (ranging random jitter) and deterministic (bias) terms at the same time;

[0080] The position and velocity solving equation of the satellite navigation positioning device is linearized to obtain a second observation equation of velocity:

[0081] z2 = Hx2 + ε

[0082] wherein, z2 = B, is an n x 1 vector,

[0083] is a 4 x 1 vector,

[0084] In the formula, z2 is a second observation, x2 is a second state quantity, and B is a Doppler observation;

[0085] The first observation equation is iterated by least squares to obtain the position information of the satellite navigation positioning device; the second observation equation is iterated by least squares to obtain the velocity information of the satellite navigation positioning device; wherein the velocity information of the satellite navigation positioning device includes the X, Y, Z direction positioning device velocity in the geocentric rectangular coordinate system;

[0086] Step seven, position and velocity accuracy detection

[0087] In each positioning solving task (period 500 ms), the pure inertial velocity in the latest received inertial auxiliary information is compared with the velocity measurement result of the satellite receiver, and the comparison method is: if the east speed of the pure inertial east speed and the east speed of the velocity measurement result is not more than 5 m / s, and the north speed of the pure inertial north speed and the north speed of the velocity measurement result is not more than 5 m / s, and the pure inertial horizontal combined speed (east speed and north speed) and the horizontal combined speed of the velocity measurement result is not more than 5 m / s, it is considered that there is no cheating interference, no pre-warning is performed, and the positioning result is normally output, otherwise it is considered that there is cheating interference, and a pre-warning is sent to the user.

[0088] In summary, the application provides a spoofing interference detection method based on pure inertial speed assistance, which utilizes the inertial assistance information output by the inertial measurement device in the navigation stage, performs Doppler consistency detection on each satellite, eliminates the spoofing signal, then performs position and speed solving of the satellite navigation positioning device, and then performs accuracy detection on the solving result, thereby improving the positioning reliability.

[0089] For the convenience of description, spatial relative terms such as "above", "upper", "top", "up", etc. can be used herein to describe the spatial positional relationship of one device or feature with other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "on" other devices or structures will be positioned "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0090] In addition, it should be noted that the use of "first", "second", and the like to qualify components is merely for the convenience of distinguishing the corresponding components, and the above terms have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the scope of protection of the present application.

[0091] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A deception interference detection method based on pure inertial velocity assistance, characterized in that, The method includes: S10. The satellite navigation and positioning device captures satellite navigation signals and performs bit synchronization and frame synchronization of the tracked satellites based on the satellite navigation signals. S20. Based on the synchronization of the satellite navigation and positioning device with the tracking satellite frame, obtain the pseudorange, Doppler observations and ephemeris parameters of each satellite; S30. Obtain the launch time of each satellite based on the pseudorange of each satellite, and obtain the position and velocity information of each satellite based on the launch time and ephemeris parameters of each satellite. S40. When the inertial measurement device is in navigation mode, acquire the inertial auxiliary information output by the inertial measurement device, and determine whether the inertial accelerations in the X, Y, and Z directions in the inertial auxiliary information are all not greater than the preset accelerations and whether the pure inertial resultant velocity in the inertial auxiliary information is not less than the preset resultant velocity. If yes, proceed to S50; otherwise, proceed to S60. The inertial auxiliary information includes the inertial accelerations and inertial velocities in the X, Y, and Z directions in the geocentric rectangular coordinate system. S50. Use the velocity information output by the inertial measurement device as the velocity information of the satellite navigation and positioning device. Based on the velocity information of the satellite navigation and positioning device and the velocity information of each satellite, obtain the satellite Doppler data back-inferred from each satellite. Remove satellites whose absolute value of the difference between the Doppler observation and the back-inferred satellite Doppler is greater than a preset threshold. Determine whether the number of satellites removed is greater than or equal to three. If so, there is deception interference. Proceed to S10. Otherwise, proceed to S60. S60. Based on the position information and pseudorange of the removed satellites, and the position information and clock error of the satellite navigation and positioning device, establish the position and velocity calculation equations of the satellite navigation and positioning device; linearize the position and velocity calculation equations of the satellite navigation and positioning device to obtain the first observation equation for position and the second observation equation for velocity. S70. Perform least squares iteration on the first observation equation to obtain the position information of the satellite navigation and positioning device; perform least squares iteration on the second observation equation to obtain the velocity information of the satellite navigation and positioning device; wherein, the velocity information of the satellite navigation and positioning device includes the X, Y, and Z velocities of the positioning device in the geocentric rectangular coordinate system; S80. Perform coordinate transformation on the X, Y, and Z inertial velocities in the geocentric rectangular coordinate system to obtain the North, Sky, and East inertial velocities in the geodetic coordinate system; perform coordinate transformation on the X, Y, and Z positioning device velocities in the geocentric rectangular coordinate system to obtain the North, Sky, and East positioning device velocities in the geodetic coordinate system. S90. Determine whether the absolute value of the difference between the eastward inertial velocity and the eastward positioning device velocity does not exceed the preset eastward velocity, the absolute value of the difference between the northward inertial velocity and the northward positioning device velocity does not exceed the preset northward velocity, and the absolute value of the difference between the sum of the eastward and northward inertial horizontal velocities and the sum of the eastward and northward positioning device horizontal velocities does not exceed the preset horizontal sum of velocities. If yes, there is no deception interference, and the position information and velocity information of the satellite navigation positioning device are used as the positioning result. Otherwise, there is deception interference, and proceed to S10.

2. The method according to claim 1, characterized in that, In S40, the preset acceleration is set to 30 m / s². 2 The preset combined velocity is set to 100m / s.

3. The method according to claim 1, characterized in that, The satellite Doppler data obtained by back-reaming each satellite is obtained using the following formula: In the formula, A is the retroactive satellite Doppler. These represent the X, Y, and Z velocities of the J-th satellite, respectively. These represent the X, Y, and Z velocities of the satellite navigation and positioning device, respectively. These are the unit vectors in the X, Y, and Z directions pointing from the satellite navigation and positioning device to the J-th satellite, respectively, t u ′ is for clock drifting.

4. The method according to claim 1, characterized in that, In the S50, the preset threshold is set to 25Hz.

5. The method according to claim 1, characterized in that, The equation for calculating the position and velocity of a satellite navigation and positioning device is established using the following formula: In the formula, ρ J Let X be the pseudorange of the J-th satellite, where J = 1, 2, ..., n, and n is the total number of satellites after elimination. J Y J Z J These are the X, Y, and Z coordinates of the J-th satellite, respectively. U Y U Z U These represent the X, Y, and Z coordinates of the satellite navigation and positioning device, respectively, where C is the speed of light, and t is the distance between the two coordinates. u This refers to the clock difference.

6. The method according to claim 1, characterized in that, The first observation equation regarding position is obtained through the following formula: z1=Hx1+ε in, x1=(X U ,Y U ,Z U ,t u ) In the formula, z1 is the first observation, H is the coefficient matrix, x1 is the first state variable, and ε is the measurement error. These are the X, Y, and Z unit vectors pointing from the satellite navigation and positioning device to the J-th satellite.

7. The method according to claim 1, characterized in that, The second observation equation regarding velocity is obtained through the following equation: z2=Hx2+ε Where z2 = B In the formula, z2 is the second observation, x2 is the second state variable, and B is the Doppler observation.

8. The method according to claim 1, characterized in that, In S90, the preset east speed, preset north speed, and preset horizontal combined speed are all set to 5 m / s.

9. The method according to claim 1, characterized in that, The rate at which the inertial measurement unit outputs inertial auxiliary information is not less than the positioning frequency of the satellite navigation and positioning device.

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