阅读说明：本技术 一种基于伪码辅助载波的改进星间测距方法 (Improved inter-satellite ranging method based on pseudo code auxiliary carrier ) 是由 燕锋 项博鸿 章跃跃 夏玮玮 谢晔 石云墀 沈连丰 于 2020-12-18 设计创作，主要内容包括：本发明公开了一种基于伪码辅助载波的改进星间测距方法,首先通过伪码测距的方法得到初始伪距值,再采用平滑伪距的模型对初始伪距值进行处理,从而得到精度更高的伪距值；然后将伪距值代入双频载波测距模型中,得到精度较高的整周模糊度；最后将精确的整周数和载波内的相位差值代入双频伪码辅助的载波测距模型中,可得星间的距离。本方法可以在星间同步的情况下达到厘米级的测距精度。(The invention discloses an improved inter-satellite ranging method based on pseudo code auxiliary carrier, which comprises the steps of firstly obtaining an initial pseudo range value by a pseudo code ranging method, and then processing the initial pseudo range value by adopting a smooth pseudo range model, thereby obtaining a pseudo range value with higher precision; then substituting the pseudo range value into a double-frequency carrier ranging model to obtain the integer ambiguity with higher precision; and finally, substituting the accurate whole cycle number and the phase difference value in the carrier into a carrier ranging model assisted by the double-frequency pseudo code to obtain the distance between the satellites. The method can achieve centimeter-level distance measurement accuracy under the condition of inter-satellite synchronization.)

1. An improved inter-satellite ranging method based on pseudo code assisted carrier is characterized by comprising the following steps:

step 1: firstly, obtaining a rough measurement pseudo range value by an inter-satellite pseudo code ranging method, and then obtaining an accurate pseudo range value by a carrier smoothing pseudo range method;

step 2: simultaneously inputting the received carrier signal and a local signal into a phase discriminator at a receiving end so as to obtain the phase difference of the carrier in the period, wherein the local signal is a signal which is well synchronized between the receiving end and the transmitting end;

and step 3: substituting the accurate pseudo range value into a dual-frequency pseudo code auxiliary carrier ranging model to obtain the whole cycle number;

and 4, step 4: and substituting the whole cycle number and the phase difference in the cycle into a double-frequency pseudo code auxiliary carrier ranging model to finally obtain an inter-satellite ranging value.

2. The improved inter-satellite ranging method based on the pseudo-code assisted carrier according to claim 1, wherein the step 1 comprises the following specific steps:

step 1-1: firstly, a coarse pseudorange value d is obtained by a pseudo code ranging method between satellites₁(t₀),d₂(t₀) Then, the pseudo range value ρ (t) with improved accuracy is obtained by the equation (1)₀)；

Wherein f is₁,f₂The carrier frequency is the dual-frequency carrier frequency of the dual-frequency pseudo code auxiliary carrier ranging model;

step 1-2: obtaining a correlation coefficient delta (t) of the phase measurement by equation (2)₀,t₁)；

Wherein, t₀Indicates the current time, t₁Denotes the next time instant, λ₁、λ₂Is the wavelength of the carrier wave and,is the carrier phase at time t₁Is measured by the measurement of (a) a,is that the carrier phase is at t₀A measured value of time of day;

step 1-3: the correlation coefficient delta (t)₀,t₁) Performing iterative computation by substituting formula (3) to finally obtain smoothed pseudorange value rho_s(ii) a P at the initial time_iSet to 0;

where w is a weight coefficient, ρ_s(t₀) Is the final smoothed pseudorange value, ρ_i(t₀) Is at t₀Intermediate measurement of the pseudoranges at time, p_i(t₁) Is at t₁Pseudorange intermediate measurements at time instants.

Technical Field

The invention belongs to the field of inter-satellite ranging, and particularly relates to an inter-satellite ranging method based on carrier smoothing pseudorange and pseudo code auxiliary carrier.

Background

With the development of mobile communication, the world-wide integrated network plays an increasingly important role. In an inter-satellite communication network, accurate ranging is an important link for ensuring the normal operation of the satellite communication network. At present, the main methods for inter-satellite ranging include pseudo code ranging, carrier ranging, and sidetone ranging. It is very important to select a suitable ranging method according to a specific situation. At present, the main research focus of inter-satellite ranging is how to utilize a pseudo code ranging method to assist a carrier ranging method and carrier ranging data to smooth pseudo range data so as to obtain a ranging value with higher precision. This shows that the main direction of future inter-satellite ranging research is still how to combine different ranging methods to better meet the requirements.

However, both the carrier smoothed pseudorange method and the pseudocode assisted carrier ranging method have corresponding drawbacks, the pseudocode assisted carrier ranging method has a problem of measurement accuracy of integer ambiguity, and the carrier smoothed pseudorange has a problem of high computational complexity.

Disclosure of Invention

The purpose of the invention is as follows: aiming at the prior art, an improved inter-satellite ranging method based on pseudo code auxiliary carrier is provided, and under the condition of improving ranging accuracy, the calculation complexity is reduced.

The technical scheme is as follows: an improved inter-satellite ranging method based on pseudo code auxiliary carrier comprises the following steps:

step 1: firstly, obtaining a rough measurement pseudo range value by an inter-satellite pseudo code ranging method, and then obtaining an accurate pseudo range value by a carrier smoothing pseudo range method;

step 2: simultaneously inputting the received carrier signal and a local signal into a phase discriminator at a receiving end so as to obtain the phase difference of the carrier in the period, wherein the local signal is a signal which is well synchronized between the receiving end and the transmitting end;

and step 3: substituting the accurate pseudo range value into a dual-frequency pseudo code auxiliary carrier ranging model to obtain the whole cycle number;

and 4, step 4: and substituting the whole cycle number and the phase difference in the cycle into a double-frequency pseudo code auxiliary carrier ranging model to finally obtain an inter-satellite ranging value.

Further, the step 1 comprises the following specific steps:

step 1-1: firstly, a coarse pseudorange value d is obtained by a pseudo code ranging method between satellites₁(t₀),d₂(t₀) Then, the pseudo range value ρ (t) with improved accuracy is obtained by the equation (1)₀)；

Wherein f is₁,f₂The carrier frequency is the dual-frequency carrier frequency of the dual-frequency pseudo code auxiliary carrier ranging model;

step 1-2: obtaining a correlation coefficient delta (t) of the phase measurement by equation (2)₀,t₁)；

Wherein, t₀Indicates the current time, t₁Denotes the next time instant, λ₁、λ₂Is the wavelength of the carrier wave and,is the carrier phase at time t₁Is measured by the measurement of (a) a,is that the carrier phase is at t₀A measured value of time of day;

step 1-3: correlating the phasesNumber delta (t)₀,t₁) Performing iterative computation by substituting formula (3) to finally obtain smoothed pseudorange value rho_s(ii) a P at the initial time_iSet to 0;

where w is a weight coefficient, ρ_s(t₀) Is the final smoothed pseudorange value, ρ_i(t₀) Is at t₀Intermediate measurement of the pseudoranges at time, p_i(t₁) Is at t₁Pseudorange intermediate measurements at time instants.

Has the advantages that: the invention relates to an improved inter-satellite ranging method based on double-frequency pseudo code assisted carrier ranging, which is different from the traditional ranging method in that a smoothed pseudo range value is used as the input of a double-frequency pseudo code assisted carrier ranging model, so that the error of the traditional ranging algorithm is improved.

Drawings

FIG. 1 is a block diagram of dual frequency pseudo code assisted carrier inter-satellite ranging in accordance with the present invention;

fig. 2 is a flow chart of the method of the present invention.

Detailed Description

The invention is further explained below with reference to the drawings.

As shown in fig. 1 and fig. 2, an improved inter-satellite ranging method based on a pseudo code auxiliary carrier, in which a carrier frequency of a transmission signal and a carrier frequency of a reception signal are set to 1.5GHZ, includes the following steps:

step 1: and at a receiving end, obtaining a rough measurement pseudo range value by a pseudo code ranging method between satellites. Because the accuracy of the rough measurement pseudo range value is not high, the rough measurement pseudo range value cannot be directly substituted into the double-frequency carrier ranging model, and therefore the accurate pseudo range value is obtained through a carrier smoothing pseudo range method.

Step 2: and simultaneously inputting the received carrier signal and the local signal into the phase discriminator at a receiving end, thereby obtaining the phase difference in the carrier period.

And step 3: and substituting the accurate pseudo range value into a dual-frequency pseudo code auxiliary carrier ranging model to obtain the whole cycle number. Since the calculation accuracy of the integer ambiguity in the pseudo code assisted carrier ranging is affected by the pseudo range obtained in step 1, the higher the accuracy of the pseudo range value obtained in step 1 is, the higher the accuracy of the integer ambiguity here is.

In this step, the smoothed pseudorange value obtained in step 1 is used to replace the coarsely measured pseudorange value in the conventional method, so that the measured value of the whole-cycle ambiguity can be greatly improved.

And 4, step 4: and substituting the whole cycle number and the phase difference in the cycle into a double-frequency pseudo code auxiliary carrier ranging model to finally obtain an inter-satellite ranging value.

Wherein, the step 1 comprises the following specific steps:

step 1-1: firstly, a coarse pseudorange value d is obtained by a pseudo code ranging method between satellites₁(t₀),d₂(t₀) Then, the accuracy of the obtained pseudo range value ρ (t) is improved by the formula (1) of the carrier smoothed pseudo range model₀)；

Wherein f is₁,f₂Is the dual-frequency carrier frequency of the dual-frequency pseudo code auxiliary carrier ranging model.

Step 1-2: after the initial pseudo range is more accurate, the correlation coefficient delta (t) of the phase measurement is obtained through the formula (2) of the carrier smoothing pseudo range model₀,t₁)；

Wherein, t₀Indicates the current time, t₁Denotes the next time instant, λ₁、λ₂Is the wavelength of the carrier wave and,is the carrier phase at time t₁Is measured by the measurement of (a) a,is that the carrier phase is at t₀A measure of time of day.

Step 1-3: the correlation coefficient delta (t)₀,t₁) Performing iterative computation by substituting formula (3) to finally obtain smoothed pseudorange value rho_s(ii) a P at the initial time_iSet to 0;

where w is a weight coefficient, ρ_s(t₀) Is the final smoothed pseudorange value, ρ_i(t₀) Is at t₀Intermediate measurement of the pseudoranges at time, p_i(t₁) Is at t₁Pseudorange intermediate measurements at time instants.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.