CN115079211B - A satellite navigation signal performance evaluation method that can be used as a basis for frequency coordination - Google Patents

Abstract

The invention belongs to the field of satellite navigation system signal design, and particularly relates to a satellite navigation signal performance evaluation method for frequency coordination work. According to the method, various performance parameters of the navigation signal are calculated through computer modeling, capturing, tracking, compatibility, multipath resistance and anti-interference performance of the navigation signal are evaluated, various performances are quantized and normalized, and the evaluation result fully reflects all performances which can be related to a navigation signal system level. The signal performance evaluation result of the method can be used as a signal design basis in the initial stage of navigation system construction, and the compatibility performance evaluation result can be used as a basis for frequency coordination work, so that the method has the advantages of being comprehensive, visual, flexible and adjustable on line.

Description

A satellite navigation signal performance evaluation method that can be used as a basis for frequency coordination

Technical field:

The invention belongs to the field of satellite navigation system signal design, and in particular relates to a satellite navigation signal performance evaluation method for frequency coordination work.

Background technique:

There are generally four forms of performance evaluation methods for satellite navigation signals: theoretical calculation, computer simulation, ground-based physical simulation, and satellite-to-ground transmission and reception verification. According to the degree of conformity with the actual situation, the effectiveness of the evaluation results of these four schemes increases in turn, but the universality decreases in turn, and the evaluation cost becomes higher and higher. Specifically in frequency coordination work, the work is carried out in the early stage of navigation system construction, and the actual signal has not yet been and cannot be transmitted for verification. At the same time, frequency coordination work involves negotiations and bargaining among multiple parties, and the supporting evaluation methods need to be both "comprehensive and flexible". Therefore, the performance evaluation method should focus on the two means of "theoretical calculation" and "computer simulation", comprehensively consider all the performance indicators of the navigation signal, and comprehensively and systematically evaluate the comprehensive performance of the navigation signal.

The "theoretical calculation" evaluation of satellite navigation signals mainly involves establishing a theoretical model for signal transmission and reception, theoretically deriving the performance of a certain aspect of the signal under specific conditions, and obtaining theoretical evaluation results. This method has the strongest universality and can be used to evaluate the performance of various aspects of navigation signals. The "computer simulation" evaluation method of satellite navigation signals is a further enhancement of the "theoretical calculation" method. It uses computers to perform more comprehensive mathematical modeling and simulation analysis of the signal transmission and reception process, establishes a signal link model between satellite constellations and receivers around the world, and uses computers to quantify the various performance manifestations of the model to further verify the theoretical evaluation results of the signal.

Theoretical calculation was first applied in the evaluation of the compatibility of GPS and other GNSS systems, which was first proposed by the United States. It is used to evaluate the interference of the positioning, navigation and timing services of GPS and other GNSS systems to the services of each system and the impact on the navigation combat capability when the positioning, navigation and timing services of GPS and other GNSS systems are used alone or simultaneously. Finally, in 2004, GPS and GALIEO reached the "Agreement on the Promotion, Provision and Use of GALIEO and GPS Satellite-Based Navigation Systems and Related Applications".

In 2007, the International Telecommunication Union issued the "Coordination Method for Interference Estimation between Satellite Radionavigation Service Systems" (ITU-R M.1831SPANISH-2007, which has been abolished and updated to ITU-RM.1831-2015 in 2015). This recommendation uses the "aggregate gain factor" as the evaluation standard for compatibility theoretical calculations. In 2009, Dr. J.W.Betz of the United States proposed an equivalent carrier-to-noise ratio evaluation method under non-white noise (WOS:000274144200021). In the tracking of the coherent early and late loop (CELP), he derived the code tracking spectrum separation coefficient to indicate the size of the code tracking error, and pointed out the influence of the high-frequency components of the signal on the equivalent carrier-to-noise ratio, which is a milestone in the theoretical calculation of signal evaluation.

In his doctoral thesis “Some Theoretical Studies on GNSS Signal Design and Evaluation”, Tang Zuping from Huazhong University of Science and Technology derived in detail the evaluation methods for code tracking accuracy and multipath error suppression capability in navigation signals, and discussed the impact of signal parameters and receiver parameters on signal performance evaluation results.

S. Wallner of the European Space Agency [Interference Computations Between GPS and Galileo [J]//In Proceedings of International Technical Meeting of the Satellite Division of the Institute of Navigation.] calculated the inter-system interference between the same-frequency signals of the GPS and GALIEO systems in the L1 band, and considered the impact of the actual signal power spectral density on the carrier-to-noise ratio calculation.

Wang Yao et al. from the 54th Institute in Shijiazhuang [Interference Analysis and Simulation for GPS/Galileo Signals[C]//The 3rd Annual Conference of China Satellite Navigation Academic] considered the influence of signal parameters such as pseudo code and telegram on the calculation of spectrum separation coefficient, and analyzed and simulated the degree of interference between GPS and Galileo systems.

In his doctoral thesis "Overall Technical Research on GNSS Compatibility and Interoperability", Liu Wei from Shanghai Jiao Tong University studied the evaluation technology of GNSS system compatibility and interoperability performance, improved the compatibility evaluation technology and determined the alarm threshold, and conducted theoretical analysis and computer simulation evaluation on the compatibility between GPS, GALIEO and BeiDou systems.

Hong Yuan et al. from Tsinghua University, in their paper "Development of Navigation Signal Performance Evaluation Software Based on MATLAB[C]//The 3rd Annual Conference of China Satellite Navigation Academic", designed a signal performance evaluation software based on MATLAB, which has the feature of flexible configuration of signal parameters. Finally, the software was used to evaluate the signal reception performance.

In her doctoral thesis "Research on GNSS Signal RF Compatibility Analysis and Design Technology", Liu Li from Shanghai Jiao Tong University considered the impact of signal loss introduced by receiver quantization, sampling and band limiting operations on the "spectral separation coefficient" and "code tracking sensitivity coefficient", and proposed a universal GNSS compatibility performance simulation evaluation scheme.

D. Borio et al. from Italy [Spectral Separation Coefficients for digital GNSS receivers//14th European Signal Processing Conference] calculated the impact of satellite navigation signals on the acquisition module of digital receivers and verified and analyzed the compatibility performance of the signals during the acquisition process.

Chu Henglin et al. from Tsinghua University [Compatibility Analysis and Experiment of S-band Satellite Navigation Signals and Adjacent Frequency Signals [J]//Telemetry and Remote Control] actually received the S-band navigation signals broadcast by an in-orbit satellite and evaluated the impact of two adjacent frequency signals, cellular communication 4G signals and WLAN signals, on the S-band navigation signals.

Summary of the invention:

The purpose of the present invention is to provide a comprehensive evaluation method for satellite navigation signal performance, which has the characteristics of "comprehensive and intuitive" and "flexible and adjustable" and can be used as a basis for frequency coordination work.

1. A method for evaluating satellite navigation signal performance that can be used as a basis for frequency coordination, characterized in that:

(1) Find and sort out the parameter information of all existing navigation signals launched in the world from the official documents released by the International Telecommunication Union (ITU);

(2) Collecting the parameter information of newly designed signals that require frequency coordination;

(3) Establishing digital simulation models of existing signals, designed signals, and loops for signal reception on a computer;

(4) Calculate the three indicators of "received power loss", "signal-to-noise-interference ratio" and "equivalent carrier-to-noise ratio" of each signal. The smaller the value of the calculation result of "received power loss", the larger the values of the calculation results of "signal-to-noise-interference ratio" and "equivalent carrier-to-noise ratio", the stronger the signal capture performance;

(5) Calculate the three indicators of "code tracking error", "code tracking error lower bound" and "Gabor bandwidth" for each signal. The smaller the values of the calculation results of "code tracking error" and "code tracking error lower bound" and the larger the value of the calculation result of "Gabor bandwidth", the stronger the tracking performance of the signal;

(6) In the presence of other signal interference, calculate the two indicators of "spectral separation coefficient" and "code tracking sensitivity coefficient" of each signal at this time. The smaller the value of the calculated results of the two indicators, the stronger the signal compatibility performance;

(7) Calculate the two indicators of "multipath error envelope" and "average multipath error" for each signal. The smaller the values of the calculated results of the two indicators, the stronger the anti-multipath performance of the signal;

(8) In the presence of other signal interference in the surrounding area, the "anti-interference quality factor" index of each signal is calculated. The larger the value of the index calculation result, the stronger the anti-interference performance of the signal;

(9) The calculation results in (4)-(8) are normalized according to the highest performance index being 100 and the lowest performance index being 60, so as to obtain the normalized values of the performance indexes of all signals and draw a radar chart of the comprehensive performance of the signals;

(10) Using the compatibility performance evaluation results of the existing signal and the design signal as the basis for frequency coordination of the design signal;

(11) Compare other performance evaluation results of existing signals and designed signals to illustrate the rationality of the designed signals.

2. The method for calculating various indicators and parameter description for evaluating signal performance according to clauses (3) to (9) of claim 1, characterized in that:

(1) In order to establish a general navigation baseband signal model, c _n is the pseudo code symbol, p(t) is the rectangular code chip, T is the coherent integration time, D(t) is the data signal, f ₀ is the carrier frequency, θ is the carrier phase, δ is the lead-lag correlator spacing, β _ι is the broadband interference signal bandwidth, β _r is the receiver front-end low-pass filter bandwidth, _CS is the received signal power, G _s (f) is the received signal normalized power spectral density, G _ι (f) is the interference signal power spectral density, C _ι is the interference signal power, N ₀ is the noise power spectral density, τ is the signal transmission delay, _AS is the signal amplitude, ι(t) is the interference signal, n(t) is the noise signal, Var(*) represents the variance of *;

(2) A general pseudo code signal can be expressed as:

(3) A broadband interference signal can be expressed as:

(4) A general navigation signal complex envelope can be expressed as:

(5) When there is no error in carrier tracking, a baseband signal stripped of the carrier and data code and then spread by pseudo code can be expressed as:

r(t)＝A _s g(t-τ)e ^jθ +n(t)+ι(t)<4>

(6) The signal "receive power loss" metric, which reflects the received power loss due to the limited receiver bandwidth, can be expressed as:

(7) Under the same receiver conditions, if interference exists, the “signal-to-noise-interference ratio” indicator, which is positively correlated with the receiver signal acquisition performance, can be expressed as:

(8) If interference exists, the signal "equivalent carrier-to-noise ratio" indicator that measures the instantaneous branch reception performance can be expressed as:

(9) The mathematical model of the “code tracking error” indicator of the coherent lead-lag loop can be expressed as:

(10) The “code tracking error lower bound” indicator of the coherent lead-lag loop is the limit value of the tracking error when the lead-lag interval approaches zero. It represents the signal tracking performance limit determined by the signal structure. Its mathematical model can be expressed as:

(11) The “Gabor bandwidth” index related to the signal power spectrum and used to evaluate the signal tracking performance can be expressed as:

(12) The “spectral separation coefficient” index, which reflects the impact of interference signals on the performance of useful signals in real-time branch acquisition, carrier tracking, and data demodulation, can be expressed as:

(13) The “code tracking sensitivity coefficient”, which reflects the degree of interference of other signals on the useful signal in the code tracking loop, can be expressed as:

(14) α represents the amplitude of the multipath signal relative to the direct signal, _δm represents the time delay of the multipath signal relative to the direct signal, and _φm represents the carrier phase of the received multipath signal. When the received signal contains one multipath signal, it can be expressed as:

(15) The “average multipath error” indicator, which is composed of the maximum and minimum multipath errors, can be expressed as:

(16) The “anti-interference quality factor” index of pseudo code tracking can be expressed as:

(17) The “anti-interference quality factor” index of carrier tracking can be expressed as:

(18) Select "Gabor bandwidth" as the quantitative indicator of navigation signal tracking performance. The maximum value of Gabor bandwidth in all evaluation results is V _{Gabor_max} , the minimum value is V _{Gabor_min} , and the Gabor bandwidth to be normalized of the current evaluation signal is V _{Gabor_unknown} . At this time, the normalized result of the tracking performance of the current evaluation signal is:

(19) Select "receiving power loss" as the capture performance quantification indicator, record the maximum receiving power loss in all evaluation results as V _{powerloss_max} , the minimum receiving power loss as V _{powerloss_min} , and the normalized receiving power loss of the current evaluation signal as V _{powerloss_unknown} . At this time, the capture performance normalization result of the current evaluation signal is:

(20) Select "spectral separation coefficient" as the compatibility performance quantitative index, record the maximum value of the spectrum separation coefficient in all evaluation results as V _{SSC_max} , the minimum value of the spectrum separation coefficient as V _{SSC_min} , and the normalized spectrum separation coefficient of the current evaluation signal as V _{SSC_unknown} . At this time, the capture performance normalization result of the current evaluation signal is:

(21) Select "average multipath error maximum value" as the quantitative index of anti-multipath performance, record the average multipath error maximum value in all evaluation results as V _{MPerror_max} , the average multipath error minimum value as V _{MPerror_min} , and the average multipath error to be normalized of the current evaluation signal as V _{MPerror_unknown} . At this time, the acquisition performance normalization result of the current evaluation signal is:

(22) Select "anti-interference quality factor" as the quantitative index of anti-interference performance, record the maximum value of anti-interference quality factor in all evaluation results as V _{Q_max} , the minimum value of anti-interference quality factor as V _{Q_min} , and the normalized anti-interference quality factor of the current evaluation signal as V _{Q_unknown} . At this time, the capture performance normalization result of the current evaluation signal is:

The present invention is aimed at the evaluation of satellite navigation signal system waveform design. Satellite navigation signal is the carrier for realizing the basic functions of the navigation system, and its core is the waveform of the signal. The navigation signal waveform mainly includes three main parameters: modulation mode, carrier frequency, and pseudo code structure, which determine the basic performance of the signal system and play a decisive role in the key performance and indicators of the navigation system such as positioning, speed measurement, timing accuracy, compatibility and interoperability, and anti-interference ability. It is the core key technology of signal system design and the input condition of many key technologies in the subsequent navigation system construction process.

Compared with the prior art, the advantages of the present invention are:

1. Comprehensive and intuitive, the present invention fully considers all the performances involved in the signal system level, and unifies these performances into a whole for comparison, fully demonstrating the advantages and disadvantages of various aspects of the signal, and can serve as the basis for signal design in the initial stage of navigation system construction.

2. The compatibility index not only calculates the impact of the design signal on the existing signal, but also fully considers the interference factors between the existing signals, which can serve as the basis for frequency coordination work.

3. The module is flexible and online adjustable, and the results can be updated at any time at the frequency coordination site to ensure the smooth progress of the work.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is an overall flow chart of a satellite navigation signal performance evaluation method that can be used as a basis for frequency coordination;

Figure 2 shows the spectrum occupancy of the existing signal and the designed signal in the B3 frequency band;

Figure 3 shows the received power loss of each signal at different receiver bandwidths;

Figure 4 shows the CELP tracking error of each signal at different carrier-to-noise ratios;

Figure 5 shows the lower bound of CELP tracking error for each signal at different carrier-to-noise ratios;

Figure 6 shows the Gabor bandwidth of each signal at different receiver bandwidths;

Figure 7 is the multipath error envelope of the B3I signal;

Figure 8 is the multipath error envelope of the B3A signal;

Figure 9 is the multipath error envelope of the E6B signal;

Figure 10 is the multipath error envelope of the B3I signal;

Figure 11 is the multipath error envelope of the P3A1 signal;

Figure 12 is the multipath error envelope of the P3A2 signal;

Figure 13 is the multipath error envelope of the P3A3 signal;

FIG14 is a graph showing the CELP tracking error of each signal under different interference bandwidths;

FIG15 is the lower bound of the CELP tracking error for each signal under different interference bandwidths;

FIG16 is a diagram showing the signal-to-noise-interference ratio of each signal under different interference bandwidths;

FIG17 is an equivalent carrier-to-noise ratio of each signal under different interference bandwidths;

FIG18 is a pseudo code tracking anti-interference quality factor of each signal under different interference bandwidths;

FIG19 is a carrier tracking anti-interference quality factor of each signal under different interference bandwidths;

Figure 20 is the comprehensive evaluation and quantification result of the B3A signal;

FIG21 is a comprehensive evaluation and quantification result of the B3I signal;

Figure 22 is the comprehensive evaluation and quantification results of the E6A signal;

FIG23 is a comprehensive evaluation and quantification result of the E6B signal;

FIG24 is a comprehensive evaluation and quantification result of the P3A1 signal;

FIG25 is a comprehensive evaluation and quantification result of the P3A2 signal;

FIG26 is a comprehensive evaluation and quantification result of the P3A3 signal.

Detailed ways

In order to clearly illustrate the working process of evaluating the performance of the navigation signal based on various evaluation indicators of the present invention, the present invention is further explained by taking the navigation B3 frequency band (1215~1300MHz) as an example in combination with the embodiments and drawings, but this should not limit the scope of protection of the present invention.

The working process is as follows:

(1) Based on the ITU Recommendation R-REC-M.1787-3-201803-I, the modulation parameters of the existing navigation signals in the B3 frequency band (1215-1300 MHz) are summarized as shown in Table 1.

(2) Arrange the design signal parameters to be coordinated on the B3 frequency band as shown in Table 2;

(3) Draw the spectrum occupancy diagram as shown in Figure 2. It can be seen from the figure that the design signal only overlaps with Beidou B3I, B3A, Galileo E6B, E6A, and GLONASS L2, but is far away from the center frequency of GLONASS L2. Therefore, for the design signal at this time, only the Beidou and Galileo signals need to be paid attention to, so the signals that need to be evaluated in the end are B3I, B3A, E6B, E6A, P3A1, P3A2, and P3A3;

(4) Model the seven signals in (3) according to formula <3>;

(5) According to formula <5>, the “receive power loss” of the seven signals in (3) at different receiver bandwidths is calculated. The results are shown in FIG3 .

(6) According to formula <8>, the “CELP tracking error” of the seven signals in (3) at different carrier-to-noise ratios is calculated, and the results are shown in FIG4 ;

(7) According to formula <9>, the “CELP tracking error lower bound” of the seven signals in (3) at different CNRs is calculated. The results are shown in FIG5 .

(8) According to formula <10>, the “Gabor bandwidth” of the seven signals in (3) at different receiver bandwidths is calculated. The results are shown in FIG6 .

(9) According to formula <11>, the “spectral separation coefficient” between the three designed signals and the four existing signals in (3) is calculated. The results are shown in Table 3.

(10) According to formula <11>, the “spectral separation coefficient” between the four existing signals in (3) is calculated. The results are shown in Table 4.

(11) According to formula <12>, the "code tracking sensitivity coefficient" of the four existing signals when the three design signals in (3) exist is calculated to obtain the interference of the design signals in (3) on the existing signals. The results are shown in Table 5.

(12) According to formula <12>, the “code tracking sensitivity coefficients” of the three design signals when the four existing signals in (3) exist are calculated to obtain the interference of the existing signals in (3) on the design signals. The results are shown in Table 6.

(13) According to formula <12>, the interference between the four existing signals in (3) is calculated. The results are shown in Table 7.

(14) Calculate the “multipath error envelope” of the seven signals in (3) according to formula <13>. The results are shown in Figures 7 to 13.

(15) When wideband interference as represented by formula <2> exists, the “CELP tracking errors” of the seven signals in (3) under different interference bandwidths are calculated according to formula <8>, and the results are shown in FIG14 ;

(16) When wideband interference as represented by formula <2> exists, the “CELP tracking error lower bound” of the seven signals in (3) under different interference bandwidths is calculated according to formula <9>, and the results are shown in FIG15 ;

(17) When wideband interference as represented by formula <2> exists, the “signal-to-noise-interference ratio” of the seven signals in (3) under different interference bandwidths is calculated according to formula <6>, and the results are shown in FIG16 ;

(18) When broadband interference as represented by formula <2> exists, the “equivalent carrier-to-noise ratio” of the seven signals in (3) under different interference bandwidths is calculated according to formula <7>, and the results are shown in FIG17 ;

(19) When wideband interference as represented by formula <2> exists, the "pseudo-code tracking anti-interference quality factor" of the seven signals in (3) under different interference bandwidths is calculated according to formula <15>, and the results are shown in FIG18;

(20) When wideband interference as represented by formula <2> exists, the “carrier tracking anti-interference quality factor” of the seven signals in (3) under different interference bandwidths is calculated according to formula <16>, and the results are shown in FIG19 ;

(21) According to formulas <17> to <21>, various indicators are quantified and normalized to obtain the comprehensive evaluation quantization results of each signal as shown in Figures 20 to 26;

(22) The evaluation results in Figures 3 to 26 illustrate the design performance of the design signal itself at the signal system level, which can be used by users to compare and choose according to their actual situation, and can serve as an important basis for signal design in the initial stage of navigation system construction;

(23) The compatibility performance of the design signals in Tables 3 to 7 and Figures 20 to 26 can be used as a basis for frequency coordination.

Table 1.

Table 2.

table 3.

SSC(dB/Hz) B3I B3A E6B E6A P3A1 -83.01 -84.30 -89.06 -84.39 P3A2 -87.85 -88.41 -86.64 -79.83 P3A3 -75.21 -79.46 -82.00 -87.08

Table 4.

SSC(dB/Hz) B3I B3A E6B E6A B3I -71.87 -84.13 -83.08 -74.79 B3A -84.13 -70.63 -84.30 -85.81 E6B -83.08 -84.30 -68.74 -86.25 E6A -74.79 -85.81 -86.25 -73.53

table 5.

Table 6.

Table 7.

Claims (2)

1. A satellite navigation signal performance evaluation method capable of being used as a frequency coordination basis is characterized by comprising the following steps:

(1) The method comprises the steps of finding and sorting out parameter information of all transmitted existing navigation signals in the world from files issued by the international telecommunication union (International Telecommunication Union, ITU) authorities;

(2) Counting parameter information of a newly designed signal needing frequency coordination work;

(3) Establishing a digital simulation model of an existing signal, a design signal and a loop for signal reception on a computer;

(4) The smaller the value of the calculation result of the "receiving power loss", the "signal noise interference ratio" and the "equivalent carrier-to-noise ratio" of each signal is calculated, the larger the value of the calculation result of the "receiving power loss", the "signal noise interference ratio" and the "equivalent carrier-to-noise ratio" is calculated, the stronger the signal capturing performance is;

(5) Calculating 3 indexes of a code tracking error, a code tracking error lower bound and a Gabor bandwidth of each signal, wherein the smaller the numerical value of the calculation results of the code tracking error and the code tracking error lower bound is, the larger the numerical value of the calculation result of the Gabor bandwidth is, and the stronger the tracking performance of the signal is;

(6) Under the condition that other signal interference exists around, calculating 2 indexes of a frequency spectrum separation coefficient and a code tracking sensitivity coefficient of each signal at the moment, wherein the smaller the numerical value of the calculation result of the 2 indexes is, the stronger the signal compatibility performance is;

(7) Calculating 2 indexes of multipath error envelope and average multipath error of each signal, wherein the smaller the numerical value of the calculation result of the 2 indexes is, the stronger the multipath resistance of the signal is;

(8) Under the condition that other signal interference exists around, calculating an anti-interference quality factor index of each signal, wherein the larger the numerical value of an index calculation result is, the stronger the anti-interference performance of the signal is;

(9) Normalizing the calculation results in (4) - (8) according to the index with highest performance being 100 and the index with lowest performance being 60 to obtain normalized values of all performance indexes of all signals, and drawing a signal comprehensive performance radar chart;

(10) The rationality of the design of the signal is illustrated by comparing the comprehensive performance evaluation results of the existing signal and the design signal, and the evaluation result can be used as the basis of the design of the signal in the initial stage of the navigation system construction;

(11) And taking the compatibility performance evaluation result of the existing signal and the design signal as a working basis when the frequency of the design signal is coordinated.

2. The satellite navigation signal performance evaluation method according to claim 1, wherein the calculation method and the parameter description of each index are as follows:

(12) In order to build a general navigation baseband signal model, C _n is a pseudo code symbol, p (T) is a rectangular chip, T is a coherent integration time, D (T) is a data signal, f ₀ is a carrier frequency, θ is a carrier phase, δ is a lead-lag correlator spacing, β _ι is a wideband interference signal bandwidth, β _r is a receiver front-end low-pass filter bandwidth, C _S is a received signal power, G _s (f) is a received signal normalized power spectral density, G _ι (f) is an interference signal power spectral density, C _ι is an interference signal power, N ₀ is a noise power spectral density, τ is a transmission delay of a signal, a _S is a signal amplitude, iota (T) is an interference signal score, N (T) is a noise signal, and Var (x) represents a variance of x;

(13) One general pseudo code signal can be expressed as:

(14) One wideband interferer may be expressed as:

(15) One general navigation signal envelope can be expressed as:

(16) When there is no error in carrier tracking, a baseband signal after carrier and data code stripping and spreading by pseudo code can be expressed as:

r(t)＝A_sg(t-τ)e^jθ+n(t)+ι(t)

(17) The signal "received power loss" indicator reflecting the received power loss due to limited receiver bandwidth can be expressed as:

(18) Under the same receiver conditions, if interference exists, the "signal-to-noise-and-interference ratio" indicator that is positively correlated to the receiver signal acquisition performance can be expressed as:

(19) If interference exists, the signal equivalent carrier-to-noise ratio indicator for measuring the receiving performance of the instant branch can be expressed as follows:

(20) The mathematical model of the "code tracking error" indicator of the coherent lead-lag loop can be expressed as:

(21) The code tracking error lower bound index of the coherent lead-lag loop is the limit value of tracking error when the lead-lag distance approaches zero, and represents the signal tracking performance limit determined by the signal structure, and the mathematical model can be expressed as follows:

(22) The "Gabor bandwidth" index related to the signal power spectrum for evaluating the signal tracking performance can be expressed as:

(23) The index of the "spectral separation coefficient" reflecting the influence of the interference signal on the performance of the useful signal such as acquisition, carrier tracking and data demodulation on the instant branch can be expressed as:

(24) The "code tracking sensitivity coefficient" index reflecting the interference level of the useful signal by other signals in the code tracking loop can be expressed as:

(25) The amplitude of the multipath signal relative to the direct signal is denoted by α, δ _m denotes the time delay of the multipath signal relative to the direct signal, Φ _m denotes the carrier phase of the received multipath signal, and the received multipath signal can be expressed as:

(26) The "average multipath error" index consisting of the maximum and minimum multipath errors can be expressed as:

(27) The "anti-interference figure of merit" indicator of pseudo code tracking may be expressed as:

(28) The "anti-interference figure of merit" indicator of carrier tracking may be expressed as:

(29) The Gabor bandwidth is selected as a quantization index of the tracking performance of the navigation signal, the maximum value of the Gabor bandwidth in all evaluation results is recorded as V _{Gabor_max}, the minimum value is recorded as V _{Gabor_min}, the to-be-normalized Gabor bandwidth of the current evaluation signal is recorded as V _{Gabor_unknown;}, and the tracking performance normalization result of the current evaluation signal is that:

(30) Selecting 'receiving power loss' as a capture performance quantization index, recording the maximum value of the receiving power loss in all evaluation results as V _{powerloss_max}, the minimum value of the receiving power loss as V _{powerloss_min}, and the to-be-normalized receiving power loss of the current evaluation signal as V _{powerloss_unknown;}, wherein the capture performance normalization result of the current evaluation signal is as follows:

(31) The 'spectrum separation coefficient' is selected as a compatibility performance quantization index, the maximum value of the spectrum separation coefficient is recorded as V _{SSC_max}, the minimum value of the spectrum separation coefficient is recorded as V _{SSC_min}, the spectrum separation coefficient to be normalized of the current evaluation signal is recorded as V _{SSC_unknown;}, and the capturing performance normalization result of the current evaluation signal is recorded as follows:

(32) Selecting 'average multipath error maximum value' as an anti-multipath performance quantization index, recording the average multipath error maximum value as V _{MPerror_max}, the average multipath error minimum value as V _{MPerror_min} in all evaluation results, and capturing the current evaluation signal when the average multipath error to be normalized of the current evaluation signal is as V _MPerror _unknown;

The performance normalization results were:

(33) The anti-interference quality factor is selected as an anti-interference performance quantization index, the maximum value of the anti-interference quality factor in all evaluation results is recorded as V _{Q_max}, the minimum value of the anti-interference quality factor is recorded as V _{Q_min}, the anti-interference quality factor to be normalized of the current evaluation signal is recorded as V _{Q_unknown;}, and the capturing performance normalization result of the current evaluation signal is that: