CN-115685261-B - Satellite navigation simulator pseudo-range measurement method based on signal synthesis amplitude-phase characteristics

Abstract

The technical scheme of the invention provides a satellite navigation simulator pseudo-range measurement method based on signal synthesis amplitude-phase characteristics, which changes one path of signal pseudo-range in a double path of satellite synthesis signals, calculates signal phase difference in a frequency domain by measuring signal amplitude change, further obtains signal time delay, finally obtains a pseudo-range actual change value, and realizes pseudo-range measurement. The method reduces the influence of signal time domain jitter on the measurement result by changing the time domain measurement into the frequency domain measurement, and simultaneously measures the relative change of the signal peak level, and the inherent noise component in the signal is counteracted, thereby reducing the noise influence and greatly improving the measurement precision.

Inventors

• LIANG WEI
• ZHONG CHONGXIA
• YAO HEJUN
• HUANG YAN
• WU XIAOYU
• XU YUAN
• GAO CHUNLIU
• WU JINTIE

Assignees

• 北京市计量检测科学研究院

Dates

Publication Date

20260512

Application Date

20210729

Claims (3)

1. 1. A satellite navigation simulator pseudo-range measurement method based on signal synthesis amplitude-phase characteristics, the method comprising: Selecting a simulator navigation system to output a satellite single carrier signal of any frequency point, and measuring a single satellite peak level of a first satellite; comparing the synthesized peak level with the single-satellite peak level, judging whether the added value of the synthesized signal amplitude is 6.02dB, and if so, judging that the signal amplitudes and phases of the two satellites are the same; changing the pseudo range of any satellite in two paths of satellite signals, testing the synthesized peak level for the second time, comparing the synthesized peak level with the single-satellite peak level to obtain a difference value, and acquiring an actual adjustment pseudo range value between the two satellite signals according to the difference value, so as to obtain the pseudo range control precision of the simulator; wherein, the difference value is obtained by comparing the synthesized peak level with the single star peak level, which comprises the following steps: comparing the synthesized peak level obtained by the second test with the single star peak level to obtain a logarithmic change value of the synthesized signal amplitude The amplitude and phase difference relationship is: ; According to the logarithmic change value of the synthesized signal amplitude Acquiring phase difference : 。
2. 2. The method of claim 1, wherein the time delay is calculated from a logarithmic change in amplitude of the composite signal Then, the actual adjustment pseudo-range value is obtained according to the time delay : ; Wherein Is periodic.
3. 3. The method of claim 1, wherein changing the pseudorange of the satellite comprises changing the pseudorange value of the satellite in one direct jump, or setting a fixed pseudorange change rate and duration, and calculating an accumulated pseudorange change value after the pseudorange duration change time.

Description

Satellite navigation simulator pseudo-range measurement method based on signal synthesis amplitude-phase characteristics Technical Field The invention relates to the field of satellite navigation pseudo-range testing, in particular to a satellite navigation simulator pseudo-range measuring method based on signal synthesis amplitude-phase characteristics. Background The global navigation satellite system (Global Navigation SATELLITE SYSTEM, GNSS) is a system that uses satellite pseudorange signals to range and achieve positioning. The satellite navigation system has the advantages of high precision, wide coverage, convenient application and the like, is widely applied to the fields of unmanned driving, intelligent traffic, intelligent agriculture, disaster monitoring and the like, and develops towards high precision, anti-interference and multi-sensor fusion in the future. The satellite navigation simulator (for short, the simulator) is a standard signal source for simulating a navigation system, can simulate carrier state scenes at any time and any place, can simulate various error models such as troposphere, ionosphere, clock error, multipath and the like, is indispensable equipment in the construction, verification and application of the satellite navigation system, is also indispensable testing verification and metering detection equipment in the whole process of designing, researching, developing, producing, maintaining and the like of a satellite navigation terminal, and is widely applied to the fields of universities, scientific research institutions, production enterprises and military industry. The simulator is used as a core device for verification and detection of navigation systems and terminal products, and the performance and the precision of the simulator are very important. The pseudo range is the distance from the satellite with error to the carrier, the simulator simulates different satellites through different channels, the time delay of the control channel is multiplied by the light speed to obtain the satellite pseudo range, and the pseudo range control precision directly reflects the simulation level of the simulator because the pseudo range is directly related to the positioning index, and the smaller and finer the pseudo range control resolution of the simulator, the smaller and more accurate the pseudo range control error. The traditional pseudo-range control precision is tested by adopting a high-speed sampling digital oscilloscope, the waveform time delay generated by the pseudo-range change of a single-channel satellite signal is tested by the oscilloscope, and the actual change value of the pseudo-range is obtained by multiplying the light speed, so that the pseudo-range control error is calculated. The simulation satellite signal can be a BPSK modulation signal or a single carrier signal, the BPSK modulation signal mainly collects change time delay of a turning point, the single carrier signal collects peak change time delay, but no matter which signal oscilloscope measures, the problems of waveform jitter and the like exist, the high-precision pseudo-range measurement below the centimeter level is seriously affected, and the uncertainty of a measurement result is large. The specific method of the prior measuring technology is that a 1PPS pulse signal output by an simulator is used as an oscilloscope reference trigger signal, a single satellite (channel) signal is simulated and output, the oscilloscope records the initial position of a waveform, the satellite pseudo-range delta d (delta d is generally the minimum pseudo-range control resolution which can be achieved) is changed, the waveform moves horizontally, the waveform ending position is recorded, the time delay delta t of the two positions of the waveform is measured by the oscilloscope, and the actual change quantity of the pseudo-range is obtained by multiplying the light speed. When the satellite signal is a BPSK modulation signal, the waveform position of the zero-crossing turning point of the signal is recorded, in actual measurement, as the turning point of the BPSK modulation signal is not a point, but is a zero-crossing curve with amplitude fluctuation, as shown in fig. 3, the turning time of the modulation signal is about 4ns, the amplitude has interference fluctuation, the waveform position recording point cannot be accurately found, the uncertainty of the measurement time delay is nanosecond, high-precision pseudo-range change cannot be measured, and meanwhile, the measurement signal is limited to the BPSK modulation mode and is not applicable to other modulation modes. When the satellite signal is single carrier wave, the peak level position of sine wave is recorded, the oscillograph displays that the waveform has jitter due to factors such as crystal oscillator stability, various noise interferences and the like, the single carrier wave jitter is recorded by using a fluorescent function, as shown in fig. 4, th