CN115955258B - A reference waveform-based navigation signal transceiver isolation adaptive cancellation method - Google Patents

Abstract

The present application relates to a reference waveform-based navigation signal transceiver isolation adaptive cancellation method. The method includes: the receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated from the transmitting antenna and the mid-high orbit navigation signal transmitted by the mid-high orbit satellite, and obtains the combined signal after the combination; transmits the signal at the entrance of the transmitter antenna The low-orbit navigation signal is used as the analog reference interference signal, and the analog cancellation is performed according to the analog reference interference signal and the combined signal to obtain the analog cancellation result; the frequency conversion and sampling are performed on the analog cancellation result to obtain the intermediate frequency digital signal, and the analog reference interference signal Perform frequency conversion and sampling to obtain a digital reference interference signal. The method can overcome the problem of unsatisfactory cancellation effect under the generated interference signal waveform, and improve the ability to suppress the interference signal.

Description

An adaptive cancellation method for navigation signal transmission and reception isolation based on reference waveform

Technical Field

The present application relates to the field of radio communication technology, and in particular to a method for adaptive cancellation of navigation signal transceiver isolation based on a reference waveform.

Background Art

Broadcasting navigation signals on low-orbit satellites and providing navigation services to users together with medium- and high-orbit satellite systems can improve the user's space observation geometry. At the same time, low-orbit satellites need to receive medium- and high-orbit navigation signals to achieve autonomous orbit determination. Therefore, for low-orbit satellites, on the one hand, they need to receive medium- and high-orbit navigation signals, and on the other hand, they need to broadcast navigation signals to the ground. The navigation signals broadcast to the ground will cause co-frequency interference to the reception of medium- and high-orbit navigation signals. Therefore, low-orbit satellites need to solve the problem of isolating the transmission and reception of co-frequency signals while receiving medium- and high-orbit navigation signals.

For the problem of transceiver isolation, the commonly used solutions currently include: optimizing the transceiver antenna and the satellite structure, reducing the degree of signal radiation leakage from the transmitting antenna to the receiving antenna. This method depends on the satellite platform and antenna design and can be used for larger satellite platforms. For small low-orbit satellite platforms, the degree of satellite isolation is limited. In addition, a cancellation method can be used to cancel the interference signal from the received signal according to its waveform. The traditional cancellation method is based on the locally generated interference signal waveform for cancellation processing. However, since the real interference signal is transmitted through the channel, including the RF channel, power amplifier, antenna, space transmission and other links, the actual received interference signal has a certain amplitude and phase distortion, and the locally generated interference signal waveform is difficult to accurately describe the above channel characteristics, resulting in unsatisfactory cancellation effect.

Summary of the invention

Based on this, it is necessary to provide a navigation signal transmission and reception isolation adaptive cancellation method based on a reference waveform to address the above technical problems.

A method for adaptive cancellation of navigation signal transmission and reception isolation based on reference waveform, the method comprising:

The receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated outward by the transmitting antenna and the medium-and-high-orbit navigation signal transmitted by the medium-and-high-orbit satellite, and obtains a combined signal after combining;

Using the low-orbit navigation signal transmitted at the entrance of the transmitter antenna as a simulated reference interference signal, performing simulated cancellation according to the simulated reference interference signal and the combined signal, and obtaining a simulated cancellation result;

Performing frequency conversion and sampling on the analog cancellation result to obtain an intermediate frequency digital signal, and performing frequency conversion and sampling on the analog reference interference signal to obtain a digital reference interference signal;

Adaptive digital cancellation is performed according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result, so as to achieve the isolation of sending and receiving simultaneous same-frequency signals.

In one of the embodiments, it also includes: inputting the digital reference interference signal into a time domain adaptive filter, and performing adaptive filtering using corresponding filter coefficients to obtain a filtered digital reference interference signal; and canceling the filtered digital reference interference signal from the intermediate frequency digital signal to obtain a digital cancellation result.

In one embodiment, the filter coefficient is calculated based on the digital cancellation result:

；

;

为迭代因子，

为共轭运算，

为滤波器系数，

为数字对消结果，

为滤波后的数字参考干扰信号。in,

is the iteration factor,

is the conjugate operation,

is the filter coefficient,

is the result of digital cancellation,

is the filtered digital reference interference signal.

In one of the embodiments, it also includes: performing power division phase shifting on the analog reference interference signal to obtain two orthogonal components of the analog reference interference signal; performing vector modulation on the two orthogonal components according to the corresponding reference carrier estimation result to obtain a vector modulated signal; and performing cancellation processing on the vector modulated signal and the combined signal to obtain a simulated cancellation result.

In one of the embodiments, the method further includes: performing power estimation on the simulation cancellation result to obtain a power estimation result of the simulation cancellation result; and adjusting the current reference carrier estimation result according to the power estimation result to:

；

;

为同相分量，

为正交分量，

为参考载波的最佳幅度，

为参考载波的最佳相位。in,

is the in-phase component,

are orthogonal components,

is the optimal amplitude of the reference carrier,

is the optimal phase of the reference carrier.

In one of the embodiments, the method further includes: performing analog power estimation on the analog cancellation result to obtain an analog power estimation result, and performing digital power estimation on the intermediate frequency digital signal to obtain a digital power estimation result;

A power estimation result of the analog cancellation result is obtained according to the analog power estimation result and the digital power estimation result.

In one of the embodiments, it also includes: traversing the phase within a preset phase search range, and obtaining the optimal phase according to the phase value when the power estimation result is the minimum; according to the power estimation result, adjusting the amplitude to minimize the power estimation result to obtain the optimal amplitude; and obtaining the current reference carrier estimation result according to the optimal phase and the optimal amplitude.

In one of the embodiments, the preset phase search range is 0~2π.

A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

The receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated outward by the transmitting antenna and the medium-and-high-orbit navigation signal transmitted by the medium-and-high-orbit satellite, and obtains a combined signal after combining;

Using the low-orbit navigation signal transmitted at the entrance of the transmitter antenna as a simulated reference interference signal, performing simulated cancellation according to the simulated reference interference signal and the combined signal, and obtaining a simulated cancellation result;

Performing frequency conversion and sampling on the analog cancellation result to obtain an intermediate frequency digital signal, and performing frequency conversion and sampling on the analog reference interference signal to obtain a digital reference interference signal;

Adaptive digital cancellation is performed according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result, so as to achieve the isolation of sending and receiving simultaneous same-frequency signals.

A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

The receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated outward by the transmitting antenna and the medium-and-high-orbit navigation signal transmitted by the medium-and-high-orbit satellite, and obtains a combined signal after combining;

Using the low-orbit navigation signal transmitted at the entrance of the transmitter antenna as a simulated reference interference signal, performing simulated cancellation according to the simulated reference interference signal and the combined signal, and obtaining a simulated cancellation result;

Performing frequency conversion and sampling on the analog cancellation result to obtain an intermediate frequency digital signal, and performing frequency conversion and sampling on the analog reference interference signal to obtain a digital reference interference signal;

Adaptive digital cancellation is performed according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result, so as to achieve the isolation of sending and receiving simultaneous same-frequency signals.

The above-mentioned method of adaptive cancellation of navigation signal transceiver isolation based on reference waveform, by collecting the low-orbit navigation signal coupled output from the transmission channel at the low-orbit receiving end, using the low-orbit navigation signal at the entrance of the transmitting antenna as the reference interference signal, isolating the combined signal containing the same frequency and the low-orbit navigation signal and the medium- and high-orbit navigation signal for transceiver, thereby eliminating the strong interference coupled in the receiving antenna and improving the cancellation effect of the interference signal. Among them, the transceiver isolation is specifically achieved by using the reference interference signal to perform interference cancellation in the signal analog channel to achieve the suppression of strong interference signals, so that the subsequent digital sampling device can work normally, and the reference interference signal sampled through the analog channel and the combined signal collected by the receiving antenna are adaptively cancelled in the digital domain. The embodiment of the present invention can overcome the problem of unsatisfactory cancellation effect under the generated interference signal waveform and improve the ability to suppress interference signals.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic flow chart of a method for adaptive cancellation of navigation signal transmission and reception isolation based on a reference waveform in one embodiment;

FIG2 is a structural block diagram of a navigation signal transmission and reception isolation adaptive cancellation device based on a reference waveform in one embodiment;

FIG3 is a block diagram of a simulation cancellation channel in one embodiment;

FIG4 is a block diagram of an adaptive digital cancellation processing module in one embodiment;

FIG5 is a schematic diagram of simulation results of power estimation results varying with phase angle and signal amplitude in a specific embodiment;

FIG6 is a structural block diagram of a navigation signal transmission and reception isolation adaptive cancellation device based on a reference waveform in a specific embodiment;

FIG. 7 is a diagram showing the internal structure of a computer device in one embodiment.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

In one embodiment, as shown in FIG1 , a method for adaptive cancellation of navigation signal transmission and reception isolation based on a reference waveform is provided, comprising the following steps:

Step 102: The receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated outward by the transmitting antenna and the medium- and high-orbit navigation signal transmitted by the medium- and high-orbit satellites to obtain a combined signal.

，发射天线202向外辐射低轨导航信号

，发射天线辐射的低轨导航信号

在空间耦合到接收天线，同时，接收天线203接收到来自中高轨卫星的中高轨导航信号对接收信号

，经过接收天线合路后，得到合路信号

，

，

对

引起强干扰。As shown in FIG2 , the structure block diagram of the navigation signal receiving and transmitting isolation adaptive cancellation device based on the reference waveform, the transmitter 201 outputs the low-orbit navigation signal broadcast to the ground through modulation frequency conversion and power amplifier amplification.

, the transmitting antenna 202 radiates the low-orbit navigation signal outward

, the low-orbit navigation signal radiated by the transmitting antenna

In space, the receiving antenna 203 receives the medium-high orbit navigation signal from the medium-high orbit satellite.

, after being combined by the receiving antenna, the combined signal is obtained

,

,

right

Causes strong interference.

Step 104: Use the low-orbit navigation signal transmitted at the transmitter antenna entrance as a simulated reference interference signal, perform simulated cancellation based on the simulated reference interference signal and the combined signal, and obtain a simulated cancellation result.

，将其送入模拟对消通道204，作为模拟对消的模拟参考干扰信号，模拟对消通道204对接收到的合路信号

进行模拟对消处理，得到模拟对消结果。Transmit the signal from the transmitter antenna entrance

, and send it to the analog cancellation channel 204 as the analog reference interference signal for analog cancellation. The analog cancellation channel 204 receives the combined signal

Perform simulation cancellation processing to obtain simulation cancellation results.

Step 106, frequency conversion and sampling are performed on the analog cancellation result to obtain an intermediate frequency digital signal, and frequency conversion and sampling are performed on the analog reference interference signal to obtain a digital reference interference signal.

，从发射机天线入口处发射信号

，将其送入参考干扰通道205进行下变频与采样处理，得到采样后的数字参考干扰信号

。The analog cancellation result obtained after the analog cancellation is input into the down-conversion module 306 for down-conversion sampling to obtain an intermediate frequency digital signal

, the signal is transmitted from the transmitter antenna entrance

, and send it to the reference interference channel 205 for down-conversion and sampling processing to obtain the sampled digital reference interference signal

.

Step 108, performing adaptive digital cancellation according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result, so as to achieve isolation of simultaneous transmission and reception of the same-frequency signal.

和数字参考干扰信号

进行数字域自适应对消处理，得到同频收发隔离对消后的数字对消结果

。The adaptive digital cancellation processing module 206 processes the digital intermediate frequency signal according to the input digital intermediate frequency signal.

and digital reference interference signal

Perform digital domain adaptive cancellation processing to obtain the digital cancellation result after isolating the same-frequency transmission and reception.

.

In the above-mentioned method of adaptive cancellation of navigation signal reception and transmission isolation based on reference waveform, the low-orbit navigation signal coupled and output from the transmission channel is collected at the low-orbit receiving end, and the low-orbit navigation signal at the entrance of the transmitting antenna is used as a reference interference signal to isolate the combined signal containing the low-orbit navigation signal of the same frequency and the medium- and high-orbit navigation signal, thereby eliminating the strong interference coupled in the receiving antenna and improving the cancellation effect of the interference signal. Among them, the transmission and reception isolation is realized specifically by using the reference interference signal to perform interference cancellation in the signal analog channel to suppress the strong interference signal, so that the subsequent digital sampling device can work normally, and the reference interference signal sampled through the analog channel and the combined signal collected by the receiving antenna are adaptively cancelled in the digital domain. The embodiment of the present invention can overcome the problem of unsatisfactory cancellation effect under the waveform of the generative interference signal and improve the ability to suppress interference signals.

In one embodiment, as shown in FIG3 , a block diagram of a simulation cancellation channel is provided, and the steps of performing simulation cancellation according to the simulation reference interference signal and the combined signal to obtain the simulation cancellation result include: performing power division phase shifting on the simulation reference interference signal to obtain two orthogonal components of the simulation reference interference signal; performing vector modulation on the two orthogonal components according to the corresponding reference carrier estimation result to obtain the vector modulated signal; performing cancellation processing on the vector modulated signal and the combined signal to obtain the simulation cancellation result. In this embodiment, the reference interference signal waveform processed by the radio frequency channel, power amplifier, etc. can be used to effectively eliminate the strong interference coupled in the receiving antenna and improve the cancellation effect of the interference signal. In addition, the design of the simulation cancellation channel of the present invention is simpler and can quickly perform simulation cancellation.

输入功分移相器301，得到模拟参考干扰信号的两路正交分量信号

和

，将正交分量信号

和

输入矢量调制模块302进行矢量调制，调制后得到的信号为

，

，其中

和

为矢量调制模块302的输入，由参考载波估计模块305处理得到。将矢量调制后的

和输入的合路信号

输入模拟模拟对消器303完成对消处理，得到模拟对消结果为

，

，将模拟对消结果送入功率估计模块304，根据输出的功率估计结果估计参考载波。Specifically, as shown in FIG3 , the simulated reference interference signal

Input the power divider phase shifter 301 to obtain two orthogonal component signals of the analog reference interference signal

and

, the orthogonal component signal

and

The input vector modulation module 302 performs vector modulation, and the signal obtained after modulation is

,

,in

and

is the input of the vector modulation module 302 and is processed by the reference carrier estimation module 305.

And the combined signal of the input

Input simulation canceller 303 to complete the cancellation process, and obtain the simulation cancellation result:

,

, the simulation cancellation result is sent to the power estimation module 304, and the reference carrier is estimated according to the output power estimation result.

In one embodiment, as shown in FIG6 , a structural block diagram of a navigation signal receiving and transmitting isolation adaptive cancellation device based on a reference waveform is provided. The steps of obtaining a reference carrier estimation result include: performing power estimation on a simulated cancellation result to obtain a power estimation result of the simulated cancellation result; and adjusting the current reference carrier estimation result according to the power estimation result to:

；

;

为同相分量，

为正交分量，

为参考载波的最佳幅度，

为参考载波的最佳相位；对模拟对消结果进行功率估计，得到模拟对消结果的功率估计结果的步骤，包括：对模拟对消结果进行模拟功率估计，得到模拟功率估计结果，对中频数字信号进行数字功率估计，得到数字功率估计结果；根据模拟功率估计结果和数字功率估计结果，得到模拟对消结果的功率估计结果；根据功率估计结果，调整当前的参考载波估计结果的步骤，包括：在预先设置的相位搜索范围内遍历相位，根据功率估计结果最小时的相位值得到最佳相位；根据功率估计结果，对幅度进行调整以使功率估计结果最小，得到最佳幅度；根据最佳相位和最佳幅度，得到当前的参考载波估计结果。in,

is the in-phase component,

are orthogonal components,

is the optimal amplitude of the reference carrier,

The invention discloses a method for obtaining an optimal phase of a reference carrier; performing power estimation on an analog cancellation result to obtain a power estimation result of the analog cancellation result, comprising: performing analog power estimation on the analog cancellation result to obtain an analog power estimation result, performing digital power estimation on an intermediate frequency digital signal to obtain a digital power estimation result; obtaining a power estimation result of the analog cancellation result according to the analog power estimation result and the digital power estimation result; and adjusting a current reference carrier estimation result according to the power estimation result, comprising: traversing the phase within a preset phase search range, obtaining an optimal phase according to a phase value when the power estimation result is minimum; adjusting an amplitude according to the power estimation result to minimize the power estimation result to obtain an optimal amplitude; and obtaining a current reference carrier estimation result according to the optimal phase and the optimal amplitude.

In this embodiment, the analog cancellation result is subjected to analog rough estimation and digital precise estimation, so that the blind search result of the reference carrier is more accurate. Specifically, as shown in FIG6 , the analog cancellation result is sent to the analog power estimator, and a rough estimation is performed to obtain an analog power estimation result. The analog cancellation result is frequency-converted and sampled to obtain an intermediate frequency digital signal. The intermediate frequency digital signal is subjected to digital power estimation to obtain a digital power estimation result after precise estimation. The power estimation result P is obtained based on the analog power estimation result and the digital power estimation result. A blind search for the best analog reference carrier is performed based on the power estimation result. The search is divided into two steps:

，寻找使得P最小的相位值，记为

；(1) Traverse the phase range from 0 to 2π

, find the phase value that makes P minimum, denoted as

;

。(2) According to the power estimation value P, adjust the amplitude A to minimize P. The corresponding amplitude is

.

In a specific embodiment, as shown in Figure 5, a schematic diagram of simulation results of power estimation results varying with phase angle and signal amplitude is provided, and the preset phase search range is 0~2π. In this embodiment, it can be seen from Figure 5 that by traversing 0~2π and different signal amplitudes, the minimum power estimation result can be found, and the corresponding angle and amplitude values are the results of blind search, and the optimal reference waveform angle and amplitude are obtained.

In one embodiment, as shown in FIG4 , a structural block diagram of an adaptive digital cancellation processing module is provided, and the steps of performing adaptive digital cancellation according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result include: inputting the digital reference interference signal into a time domain adaptive filter, and performing adaptive filtering using the corresponding filter coefficient to obtain a filtered digital reference interference signal; canceling the filtered digital reference interference signal from the intermediate frequency digital signal to obtain a digital cancellation result. In this embodiment, digital cancellation is performed using a digital reference waveform and an intermediate frequency digital signal output by an analog cancellation channel, which can further cancel the interference signal in the intermediate frequency digital signal, and analog cancellation and digital cancellation are used to eliminate the influence of non-ideal factors of channels such as radio frequency and power amplifier on the reference waveform, thereby improving the cancellation effect of the transmit-receive isolation.

输入下变频采样模块401进行下变频和采样，得到采样后的数字信号

，将

作为数字对消的数字参考干扰信号，送入滤波器402，滤波器402为时域自适应滤波器，得到滤波后的信号

，

，其中，

为自适应滤波器的系数，

为卷积运算。将

和

送入数字对消器303，从

中将滤波后的数字参考干扰信号对消掉，得到数字对消结果

，

，将数字对消结果

输入滤波器系数计算模块404进行迭代计算。Specifically, the simulated reference interference signal

The input down-conversion sampling module 401 performs down-conversion and sampling to obtain the sampled digital signal.

,Will

The digital reference interference signal used as digital cancellation is sent to filter 402, which is a time domain adaptive filter to obtain the filtered signal

,

,in,

are the coefficients of the adaptive filter,

is the convolution operation.

and

Sent to the digital canceller 303, from

The filtered digital reference interference signal is cancelled to obtain the digital cancellation result.

,

, cancel the numbers and get the result

The input filter coefficient calculation module 404 performs iterative calculations.

In one embodiment, the step of obtaining the filter coefficients includes: calculating the filter coefficients according to the digital cancellation results as follows:

；

;

为迭代因子，

为共轭运算，

为滤波器系数，

为数字对消结果，

为滤波后的数字参考干扰信号。在本实施例中，根据数字对消结果计算滤波器系数，具体地，迭代因子可取0.0001。in,

is the iteration factor,

is the conjugate operation,

is the filter coefficient,

is the result of digital cancellation,

is the filtered digital reference interference signal. In this embodiment, the filter coefficient is calculated according to the digital cancellation result. Specifically, the iteration factor may be 0.0001.

It should be understood that, although the various steps in the flowchart of FIG. 1 are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in FIG. 1 may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be shown in FIG7. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected via a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for adaptive cancellation of navigation signal reception and transmission isolation based on a reference waveform is implemented. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covered on the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

Those skilled in the art will understand that the structure shown in FIG. 7 is merely a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method in the above embodiment when executing the computer program.

In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method in the above embodiment are implemented.

Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and/or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims (7)

1. A navigation signal receiving and transmitting isolation self-adaptive cancellation method based on a reference waveform, which is characterized by comprising the following steps:

the receiving antenna of the low-orbit satellite simultaneously receives the low-orbit navigation signal radiated outwards by the transmitting antenna and the medium-high-orbit navigation signal transmitted by the medium-high-orbit satellite to obtain a combined signal after combining;

taking a low-rail navigation signal transmitted at an antenna inlet of a transmitter as a simulation reference interference signal, and performing simulation cancellation according to the simulation reference interference signal and the combined signal to obtain a simulation cancellation result;

performing frequency conversion and sampling on the analog cancellation result to obtain an intermediate frequency digital signal, and performing frequency conversion and sampling on the analog reference interference signal to obtain a digital reference interference signal;

performing self-adaptive digital cancellation according to the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result so as to realize receiving and transmitting isolation of the simultaneous same-frequency signals;

the step of obtaining the reference carrier estimation result includes:

performing power estimation on the simulation cancellation result to obtain a power estimation result of the simulation cancellation result;

according to the power estimation result, the current reference carrier estimation result is adjusted as follows:

，

wherein ,

is an in-phase component>

Is a quadrature component->

For the optimal amplitude of the reference carrier, +.>

Is the best phase of the reference carrier.

2. The method of claim 1, wherein the step of performing adaptive digital cancellation based on the digital reference interference signal and the intermediate frequency digital signal to obtain a digital cancellation result comprises:

inputting the digital reference interference signal into a time domain adaptive filter, and performing adaptive filtering by using a corresponding filter coefficient to obtain a filtered digital reference interference signal;

and canceling the filtered digital reference interference signals from the intermediate frequency digital signals to obtain digital cancellation results.

3. The method of claim 2, wherein the step of obtaining the filter coefficients comprises:

and calculating according to the digital cancellation result to obtain a filter coefficient as follows:

，

wherein ,

for the iteration factor->

For conjugate operation, ++>

For the filter coefficients +.>

In order to obtain the result of the digital cancellation,

is a filtered digital reference interference signal.

4. The method of claim 1, wherein the step of performing analog cancellation based on the analog reference interference signal and the combined signal to obtain an analog cancellation result comprises:

performing power division phase shift on the analog reference interference signal to obtain two paths of orthogonal components of the analog reference interference signal;

vector modulation is carried out on the two paths of orthogonal components according to the corresponding reference carrier estimation result, and a signal after vector modulation is obtained;

and carrying out cancellation processing on the vector modulated signal and the combined signal to obtain an analog cancellation result.

5. The method of claim 1 wherein the step of performing power estimation on the simulated cancellation results to obtain power estimation results for the simulated cancellation results comprises:

performing analog power estimation on the analog cancellation result to obtain an analog power estimation result, and performing digital power estimation on the intermediate frequency digital signal to obtain a digital power estimation result;

and obtaining a power estimation result of the simulation cancellation result according to the simulation power estimation result and the digital power estimation result.

6. The method of claim 1, wherein the step of adjusting the current reference carrier estimate based on the power estimate comprises:

traversing the phase in a preset phase searching range, and obtaining an optimal phase according to a phase value when a power estimation result is minimum;

according to the power estimation result, adjusting the amplitude to minimize the power estimation result to obtain the optimal amplitude;

and obtaining a current reference carrier estimation result according to the optimal phase and the optimal amplitude.

7. The method of claim 1, wherein the preset phase search range is 0-2 pi.

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