CN111458730B - GNSS carrier tracking method based on Doppler residual estimation and receiver - Google Patents
GNSS carrier tracking method based on Doppler residual estimation and receiver Download PDFInfo
- Publication number
- CN111458730B CN111458730B CN202010302731.7A CN202010302731A CN111458730B CN 111458730 B CN111458730 B CN 111458730B CN 202010302731 A CN202010302731 A CN 202010302731A CN 111458730 B CN111458730 B CN 111458730B
- Authority
- CN
- China
- Prior art keywords
- tracking
- doppler
- carrier
- module
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/24—Acquisition or tracking or demodulation of signals transmitted by the system
- G01S19/29—Acquisition or tracking or demodulation of signals transmitted by the system carrier including Doppler, related
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
- G01S19/24—Acquisition or tracking or demodulation of signals transmitted by the system
- G01S19/30—Acquisition or tracking or demodulation of signals transmitted by the system code related
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
Abstract
The invention discloses a GNSS carrier tracking method based on Doppler residual estimation and a receiver, wherein the receiver comprises a receiving antenna, a radio frequency front-end module, a baseband signal processing module, a positioning resolving module and a tracking parameter prediction module, and the carrier tracking method comprises the following steps: the radio frequency front end module receives a GNSS signal transmitted by the receiving antenna and processes the GNSS signal to acquire a digital intermediate frequency signal; the baseband signal processing module captures and tracks the digital intermediate frequency signal to obtain tracking data; the positioning resolving module acquires positioning information according to the tracking data; a tracking parameter prediction module obtains a Doppler prediction result; and the baseband signal processing module tracks the carrier signal of the next epoch by using Doppler residual estimation. The invention can enlarge the traction range of carrier tracking errors, enhance the adaptability of a loop to dynamic signals and effectively improve the tracking robustness of GNSS reception in a high dynamic scene.
Description
Technical Field
The invention relates to a GNSS carrier tracking method based on Doppler residual estimation and a receiver.
Background
The satellite navigation positioning technology has basically replaced the ground-based radio navigation, the traditional geodetic survey and the astronomical survey navigation positioning technology at present, and promotes the brand new development of the field of geodetic survey and navigation positioning. Nowadays, the GNSS system is not only an infrastructure of national safety and economy, but also an important mark for embodying the status of modernized big countries and the national comprehensive strength. Due to the important significance in politics, economy, military and other aspects, the major military countries and the economic bodies in the world compete to develop independent and autonomous satellite navigation systems.
The gnss (global Navigation Satellite system) refers to four global Navigation positioning systems including the us GPS, russian GLONASS, Galileo in europe and Beidou in our country, and can provide uninterrupted and high-precision global Navigation signal resources for users, thereby realizing all-weather real-time positioning, speed measurement and time service functions. The GNSS is widely applied to various fields such as navigation, surveying and mapping, disaster monitoring and scientific research at present, and along with the continuous improvement and development of the GNSS technology, the receiver or the processing chip is expected to break through the limits of cost, power consumption, size and the like, and can be assembled on intelligent terminals such as various foundation air-based space bases and the like, so that the development of positioning technologies such as automatic driving, unmanned aerial vehicles and space vehicles can be greatly promoted. In these application scenarios, signals are often degraded due to the dynamics of users, the openness of signal propagation, and the complexity of the receiving environment, which seriously damages the service performance of the GNSS, such as availability, reliability, continuity, and the like.
The concrete expression is as follows: 1. for a carrier moving at a high speed, the signal frequency is influenced by the Doppler effect and changes rapidly, and a conventional tracking algorithm cannot track the dynamic change of a signal in time, so that the receiver is easy to lose lock; 2. in urban areas with high buildings, dense trees and serious electromagnetic radiation pollution, GNSS signals are easily influenced by shielding, multipath, interference and the like to cause signal energy attenuation and phase distortion, and the tracking measurement error and even the positioning interruption of a receiver caused by the signal energy attenuation and the phase distortion are increased; 3. the GNSS signal is an open transmission channel from a satellite transmitting end to a user receiving end, and the influence of atmosphere such as ionosphere troposphere and the like in the GNSS signal can cause time-varying and random delay and flicker of the GNSS signal and influence the normal work of a receiver.
GNSS signal tracking in complex environments is a challenge and difficulty currently encountered by all receivers. With the increasing demands on positioning accuracy and coverage of applications such as mobile internet based on location services, the contradiction between the high GNSS dependency of users and receiver robustness becomes more prominent. In order to improve the robustness and reliability of the receiver, it is necessary to adopt an advanced tracking algorithm to improve the dynamic adaptation range, the interference resistance and the like of the receiver.
Disclosure of Invention
The technical problem to be solved by the invention is to overcome the defects of poor adaptability and low anti-interference capability of a receiver tracking algorithm to dynamic signals in the prior art, provide an adaptability cavity to the dynamic signals, and effectively improve the tracking robustness of GNSS reception in a high dynamic scene.
The invention solves the technical problems through the following technical scheme:
a GNSS carrier tracking method based on Doppler residual estimation is used for a receiver and is characterized in that the receiver comprises a receiving antenna, a radio frequency front end module, a baseband signal processing module, a positioning resolving module and a tracking parameter predicting module, and the GNSS carrier tracking method comprises the following steps:
the radio frequency front-end module receives a GNSS signal transmitted by the receiving antenna and processes the GNSS signal to acquire a digital intermediate frequency signal;
the baseband signal processing module captures and tracks the digital intermediate frequency signal to obtain tracking data, wherein the tracking data comprises a Doppler tracking result;
the positioning resolving module acquires positioning information according to the tracking data;
the tracking parameter prediction module reversely deduces the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
and the baseband signal processing module is used for comparing the Doppler tracking result with the Doppler prediction result to obtain Doppler residual estimation and tracking the carrier signal of the next epoch by using the Doppler residual estimation.
The existing GNSS carrier tracking uses a frequency discriminator to assist a phase discriminator, so that the dynamic adaptability and the error traction range are improved. The nature of the tracking loop vulnerability cannot still be changed. The method using doppler residual estimation is essentially the concept of doppler assistance for each individual tracking channel using the positioning information of multiple satellite channels. If the signals of the channels track normally, the original Doppler estimate and the positioning Doppler estimate of each channel should be consistent, and the residual error is small. When a single tracking channel is affected by interference and tracking is unstable, the original Doppler estimation of the channel is detected through the information of positioning Doppler, if the error is large, the Doppler of the interference channel can be pulled back to a normal level, which is equivalent to an assistance of other normal satellite channels to the fault channel.
Preferably, the baseband signal processing module includes a correlator, a phase detector, a frequency detector, a filter and an NCO, and the baseband signal processing module performs acquisition and tracking processing on the digital intermediate frequency signal to obtain a carrier signal includes:
the correlator correlates the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of a homodromous branch and an orthogonal branch, and respectively sends the correlation values to a phase discriminator and a frequency discriminator to obtain a tracking error of a carrier phase and a tracking error of a Doppler frequency, and then sends the tracking errors to the filter;
the filter carries out filtering and noise reduction on the tracking error of the carrier phase and the tracking error of the Doppler frequency and then transmits the signals to the NCO;
and the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
Preferably, the receiver further includes a signal-to-carrier-to-noise ratio estimator, and the GNSS carrier tracking method further includes:
and the signal carrier-to-noise ratio estimator receives the correlation value and outputs signal quality data according to the correlation value.
Preferably, the baseband signal processing module further includes a determining module, and the GNSS carrier tracking method further includes:
the judging module is used for judging whether to carry out positioning calculation, if so, the positioning calculation module obtains positioning information according to the tracking data, and if not, the judging module is used for judging whether to carry out positioning calculation or not, if so, the positioning calculation module obtains positioning information according to the tracking data:
transmitting tracking data to the filter;
the filter carries out filtering and noise reduction on the tracking error of the carrier phase and the tracking error of the Doppler frequency and then transmits the signals to the NCO;
and the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency, and then outputs a carrier signal to the positioning resolving module according to the current carrier phase and the Doppler tracking result.
Preferably, the GNSS carrier tracking method further includes:
the filter carries out filtering and noise reduction on Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO generates a recurring carrier signal according to the latest tracking result.
Preferably, the filter includes a system model and an observation model for carrier tracking, wherein the system noise of the carrier signal is determined by crystal oscillator phase noise and dynamic random walk noise, the observed noise variance output by the phase detector and the frequency detector is determined by signal carrier-to-noise ratio, the observed noise variance of the doppler residual is determined by the estimated value of the clock drift output by the positioning calculation module, and the filter gain is determined according to the system noise and the observation noise model.
The invention also provides a receiver which is characterized by comprising a receiving antenna, a radio frequency front-end module, a baseband signal processing module, a positioning resolving module and a tracking parameter predicting module,
the radio frequency front end module is used for receiving GNSS signals transmitted by the receiving antenna and processing the GNSS signals to acquire digital intermediate frequency signals;
the baseband signal processing module is used for acquiring and tracking the digital intermediate frequency signal to obtain tracking data, and the tracking data comprises a Doppler tracking result;
the positioning resolving module is used for acquiring positioning information according to the tracking data;
the tracking parameter prediction module is used for reversely deducing the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
the baseband signal processing module is further configured to compare the doppler tracking result with the doppler prediction result to obtain a doppler residual estimation, and perform carrier signal tracking of a next epoch using the doppler residual estimation.
The receiver is a receiver of a GNSS.
Preferably, the baseband signal processing module comprises a correlator, a phase detector, a frequency detector, a filter, an NCO and a Doppler residual estimator,
the correlator is used for correlating the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of a homodromous branch and an orthogonal branch, respectively sending the correlation values to the phase discriminator and the frequency discriminator to obtain a tracking error of a carrier phase and a tracking error of a Doppler frequency, and then sending the tracking errors to the filter;
the filter is used for filtering and denoising the tracking error of the carrier phase and the tracking error of the Doppler frequency, and then transmitting the filtered and denoised tracking error to the NCO;
and the NCO is used for generating a recurrent carrier signal according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
And the Doppler residual error estimator is used for calculating Doppler residual error estimation according to tracking data transmitted by the NCO and Doppler prediction results obtained in the direction of the sight of the satellite channels.
Preferably, the first and second liquid crystal films are made of a polymer,
the filter is also used for filtering and denoising the Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO is used for generating a recurrent carrier signal according to the latest tracking result.
Preferably, the filter includes a system model and an observation model for carrier tracking, wherein the system noise of the carrier signal is determined by crystal oscillator phase noise and dynamic random walk noise, the observed noise variance output by the phase detector and the frequency detector is determined by signal carrier-to-noise ratio, the observed noise variance of the doppler residual is determined by the estimated value of the clock drift output by the positioning calculation module, and the filter gain is determined according to the system noise and the observation noise model.
On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The positive progress effects of the invention are as follows:
according to the invention, the Doppler error observed quantity output by the frequency discriminator is used for assisting carrier tracking, compared with the phase error output by the phase discriminator, the traction range of the carrier tracking error can be enlarged, the adaptability of a loop to dynamic signals is enhanced, and the tracking robustness of GNSS reception in a high dynamic scene can be effectively improved.
The invention uses the signal carrier-to-noise ratio C/N0The filtering gain is controlled, the influence caused by signal energy attenuation and phase distortion caused by multipath, interference, ionosphere flicker and the like can be inhibited, and the tracking precision is improved.
The invention carries out Doppler residual estimation by using the positioning information solved by a plurality of satellite channels, can assist by using Doppler residual observed quantity under the condition that a certain satellite is shielded or the output of an interference phase discriminator and a frequency discriminator is invalid, and increases the robustness of a receiver.
Drawings
Fig. 1 is a schematic structural diagram of a receiver according to embodiment 1 of the present invention.
Fig. 2 is another schematic structural diagram of a receiver according to embodiment 1 of the present invention.
Fig. 3 is a flowchart of a GNSS carrier tracking method according to embodiment 1 of the present invention.
Fig. 4 is a flowchart of a GNSS carrier tracking method according to embodiment 1 of the present invention.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
Example 1
Referring to fig. 1 and 2, the present embodiment provides a receiver, which includes a receiving antenna 11, a radio frequency front end module 12, a baseband signal processing module 13, a positioning calculation module 14, and a tracking parameter prediction module.
The radio frequency front end module is used for receiving GNSS signals transmitted by the receiving antenna and processing the GNSS signals to acquire digital intermediate frequency signals;
the GNSS signal is received by the antenna of the receiver, and is converted into a digital intermediate frequency signal by the radio frequency front end module through down-conversion, amplification and filtering, sampling and quantization and the like, and the digital intermediate frequency signal is sent to the baseband signal processing module.
The baseband signal processing module is used for acquiring and tracking the digital intermediate frequency signal to obtain tracking data, and the tracking data comprises a Doppler tracking result;
and the baseband signal processing module captures the digital intermediate frequency signal to obtain the initial estimation of parameters such as the number, the code delay, the Doppler frequency and the like of the visible satellite.
The positioning resolving module is used for acquiring positioning information according to the tracking data;
the tracking data in this embodiment includes code delay, carrier phase and doppler frequency. And the positioning resolving module extracts navigation messages according to tracking data such as code delay, carrier phase, Doppler frequency and the like, calculates the satellite position and resolves positioning information such as user position speed and the like.
The positioning information includes: satellite ephemeris, receiver position velocity information, receiver clock bias.
In this embodiment, the tracking parameter prediction module is provided in the receiver as a separate module, and in other embodiments, the tracking parameter prediction module may be a sub-module in the positioning solution module.
The tracking parameter prediction module is used for reversely deducing the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
the tracking parameter prediction module calculates the Doppler prediction result of the next epoch satellite relative to the receiver.
The baseband signal processing module is further configured to compare the doppler tracking result with the doppler prediction result to obtain a doppler residual estimation, and perform carrier signal tracking of a next epoch using the doppler residual estimation.
In this embodiment, the doppler prediction result forms feedback to the doppler tracking result. The doppler tracking results are further calibrated.
Specifically, the phase-locked loop structure is used to initialize the carrier tracking during the receiver baseband signal processing stage. Referring to fig. 2, the baseband signal processing module includes a correlator 21, a phase detector 22, a frequency detector 23, a filter 24, an NCO (numerically controlled oscillator) 25, and a doppler residual estimator 26.
The correlator is used for correlating the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of a homodromous branch and an orthogonal branch, respectively sending the correlation values to the phase discriminator and the frequency discriminator to obtain a tracking error of a carrier phase and a tracking error of a Doppler frequency, and then sending the tracking errors to the filter;
the filter is used for filtering and denoising the tracking error of the carrier phase and the tracking error of the Doppler frequency, and then transmitting the filtered and denoised tracking error to the NCO;
and the NCO is used for generating a recurrent carrier signal according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
The receiver further comprises a signal carrier to noise ratio estimator for receiving the correlation values and outputting signal quality data according to the correlation values.
The filter is also used for filtering and denoising the Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO is used for generating a recurrent carrier signal according to the latest tracking result.
And the Doppler residual error estimator is used for calculating Doppler residual error estimation according to tracking data transmitted by the NCO and Doppler prediction results obtained in the direction of the sight of the satellite channels.
The embodiment provides an optimized filter, where the filter includes a system model and an observation model for carrier tracking, where the system noise of a carrier signal is determined by crystal oscillator phase noise and dynamic random walk noise, an observation noise variance output by a phase detector and a frequency detector is determined by a signal carrier-to-noise ratio, an observation noise variance of a doppler residual is determined by an estimated value of a clock drift output by the positioning and resolving module, and a filter gain is determined according to the system noise and the observation noise model.
And a carrier tracking loop in the baseband signal processing unit sends Doppler residual errors, phase and Doppler errors output by the phase discriminator and the frequency discriminator and other observed quantities to a loop filter for filtering and noise reduction, and is used for generating a carrier phase and Doppler tracking result at a new moment and driving an NCO to generate a new local reproduction signal for tracking a new epoch.
The baseband signal processing module further comprises a judging module, and the GNSS carrier tracking method further comprises:
the judging module is used for judging whether to carry out positioning calculation, if so, the positioning calculation module obtains positioning information according to the tracking data, and if not, the judging module is used for judging whether to carry out positioning calculation or not, if so, the positioning calculation module obtains positioning information according to the tracking data:
transmitting tracking data to the filter;
the filter carries out filtering and noise reduction on the tracking error of the carrier phase and the tracking error of the Doppler frequency and then transmits the signals to the NCO;
and the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency, and then outputs a carrier signal to the positioning resolving module according to the current carrier phase and the Doppler tracking result.
And a tracking module in the baseband signal processing unit initializes each satellite channel according to the acquisition result, and each tracking channel is divided into a code tracking loop and a carrier tracking loop and is respectively used for acquiring code delay and accurate estimation of carrier phase and Doppler frequency. And adjusting the tracking strategy of the carrier tracking loop according to whether the positioning calculation module outputs effective position and speed information. The initial phase relies only on the phase detector and frequency detector outputs to obtain an effective estimate of the carrier parameters.
In this embodiment, the phase-locked loop is a loop structure, the NCO generates a more accurate carrier signal by using a tracking error of a carrier phase and a doppler frequency and a doppler residual, the carrier signal is transmitted to the positioning calculation module for a latest positioning calculation, the doppler residual is generated according to the positioning calculation, and is transmitted to the correlator for generating the tracking error, the latest doppler residual and the tracking error are transmitted to the NCO for completing signal processing of one epoch, and the signal processing process is looped to make the carrier signal more accurate.
In the next epoch, the NCO generates carrier signals according to the latest tracking error and the Doppler residual error and respectively transmits the carrier signals to the correlator and the positioning resolving module.
Referring to fig. 3, with the receiver, the present embodiment further provides a GNSS carrier tracking method, including:
102, the positioning resolving module acquires positioning information according to the tracking data;
103, the tracking parameter prediction module reversely deduces the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
and step 104, the baseband signal processing module compares the Doppler tracking result with the Doppler prediction result to obtain a Doppler residual estimation and tracks the carrier signal of the next epoch by using the Doppler residual estimation.
And the positioning settlement module carries out positioning calculation according to the latest carrier signal, namely the tracking result.
Step 101 comprises:
and 1014, the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
The positioning resolving module acquires positioning information according to tracking data such as code delay, carrier phase and Doppler tracking result
Using the correlation value of step 1011, the GNSS carrier tracking method includes:
and the signal carrier-to-noise ratio estimator receives the correlation value and outputs signal quality data according to the correlation value.
Referring to fig. 4, further, the present embodiment also provides a GNSS carrier tracking method capable of selecting a tracking policy, specifically:
the baseband signal processing module further includes a determining module, and the step 1012 and the step 1013 include:
and step 203, the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
And then outputting a carrier signal to the positioning resolving module according to the current carrier phase and the Doppler tracking result.
Step 104 comprises:
the filter carries out filtering and noise reduction on Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO generates a recurring carrier signal according to the latest tracking result.
Further, the filter comprises a system model and an observation model of carrier tracking, wherein the system noise of a carrier signal is determined by crystal oscillator phase noise and dynamic random walk noise, the observation noise variance output by the phase discriminator and the frequency discriminator is determined by a signal carrier-to-noise ratio, the observation noise variance of the Doppler residual is determined by an estimated value of a clock drift output by the positioning resolving module, and the filter gain is determined according to the system noise and the observation noise model.
In the embodiment, the error is further calibrated by using the Doppler residual error, so that the Doppler frequency is more accurate, the carrier signal is more accurate, and the positioning is more accurate.
In the embodiment, the carrier tracking is assisted by using the Doppler error observed quantity output by the frequency discriminator, and compared with a phase error output by a pure phase discriminator, the traction range of the carrier tracking error can be enlarged, the adaptability of a loop to dynamic signals is enhanced, and the tracking robustness of GNSS reception in a high-dynamic scene can be effectively improved.
This embodiment uses the signal-to-carrier-to-noise ratio C/N0The filtering gain is controlled, the influence caused by signal energy attenuation and phase distortion caused by multipath, interference, ionosphere flicker and the like can be inhibited, and the tracking precision is improved.
In the embodiment, the doppler residual estimation is performed by using the positioning information obtained by resolving a plurality of satellite channels, so that under the condition that a certain satellite is blocked or the outputs of the phase discriminator and the frequency discriminator are invalid, the doppler residual observed quantity can be used for assisting, and the robustness of the receiver is improved.
While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.
Claims (10)
1. A GNSS carrier tracking method based on Doppler residual estimation is used for a receiver, and is characterized in that the receiver comprises a receiving antenna, a radio frequency front end module, a baseband signal processing module, a positioning resolving module and a tracking parameter predicting module, and the GNSS carrier tracking method comprises the following steps:
the radio frequency front-end module receives a GNSS signal transmitted by the receiving antenna and processes the GNSS signal to acquire a digital intermediate frequency signal;
the baseband signal processing module captures and tracks the digital intermediate frequency signal to obtain tracking data, wherein the tracking data comprises a Doppler tracking result;
the positioning resolving module acquires positioning information according to the tracking data;
the tracking parameter prediction module reversely deduces the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
and the baseband signal processing module is used for comparing the Doppler tracking result with the Doppler prediction result to obtain Doppler residual estimation and tracking the carrier signal of the next epoch by using the Doppler residual estimation.
2. The GNSS carrier tracking method of claim 1, wherein the baseband signal processing module includes a correlator, a phase detector, a frequency detector, a filter, and an NCO, and the baseband signal processing module performs acquisition and tracking processing on the digital intermediate frequency signal to obtain tracking data includes:
the correlator correlates the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of a homodromous branch and an orthogonal branch, and respectively sends the correlation values to a phase discriminator and a frequency discriminator to obtain a tracking error of a carrier phase and a tracking error of a Doppler frequency, and then sends the tracking errors to the filter;
the filter carries out filtering and noise reduction on the tracking error of the carrier phase and the tracking error of the Doppler frequency and then transmits the signals to the NCO;
and the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency.
3. The GNSS carrier tracking method of claim 2 wherein the receiver further includes a signal-to-carrier-to-noise ratio estimator, the GNSS carrier tracking method further comprising:
and the signal carrier-to-noise ratio estimator receives the correlation value and outputs signal quality data according to the correlation value.
4. The GNSS carrier tracking method according to claim 2, wherein the baseband signal processing module further includes a determining module, the GNSS carrier tracking method further comprising:
the judging module judges whether to carry out positioning calculation, if so, the positioning calculation module obtains positioning information according to the tracking data, and if not:
transmitting tracking data to the filter;
the filter carries out filtering and noise reduction on the tracking error of the carrier phase and the tracking error of the Doppler frequency and then transmits the signals to the NCO;
and the NCO updates the carrier phase and the Doppler tracking result according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency, and then outputs a carrier signal to the positioning resolving module according to the current carrier phase and the Doppler tracking result.
5. The GNSS carrier tracking method of claim 2 further comprising:
the filter carries out filtering and noise reduction on Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO generates a recurring carrier signal according to the latest tracking result.
6. The GNSS carrier tracking method of claim 4 wherein the filter includes a system model and an observation model of carrier tracking, wherein the system noise of the carrier signal is determined by crystal phase noise and dynamic random walk noise, wherein the observed noise variance of the output of the phase detector and the frequency detector is determined by the signal-to-carrier-to-noise ratio, wherein the observed noise variance of the doppler residual is determined by the estimated value of the clock drift output by the positioning solution module, and wherein the filter gain is determined based on the system noise and the observation noise model.
7. A receiver is characterized by comprising a receiving antenna, a radio frequency front-end module, a baseband signal processing module, a positioning resolving module and a tracking parameter predicting module,
the radio frequency front end module is used for receiving GNSS signals transmitted by the receiving antenna and processing the GNSS signals to acquire digital intermediate frequency signals;
the baseband signal processing module is used for acquiring and tracking the digital intermediate frequency signal to obtain tracking data, and the tracking data comprises a Doppler tracking result;
the positioning resolving module is used for acquiring positioning information according to the tracking data;
the tracking parameter prediction module is used for reversely deducing the satellite channel sight according to the positioning information to obtain a Doppler prediction result in the satellite channel sight direction;
the baseband signal processing module is further configured to compare the doppler tracking result with the doppler prediction result to obtain a doppler residual estimation, and perform carrier signal tracking of a next epoch using the doppler residual estimation.
8. The receiver of claim 7 wherein said baseband signal processing module comprises a correlator, a phase detector, a frequency detector, a filter, an NCO, and a Doppler residual estimator,
the correlator is used for correlating the digital intermediate frequency signal and a recurrent carrier signal generated by the NCO to obtain correlation values of a homodromous branch and an orthogonal branch, respectively sending the correlation values to the phase discriminator and the frequency discriminator to obtain a tracking error of a carrier phase and a tracking error of a Doppler frequency, and then sending the tracking errors to the filter;
the filter is used for filtering and denoising the tracking error of the carrier phase and the tracking error of the Doppler frequency, and then transmitting the filtered and denoised tracking error to the NCO;
the NCO is used for generating a recurrent carrier signal according to the latest tracking error of the carrier phase and the latest tracking error of the Doppler frequency;
and the Doppler residual error estimator is used for calculating Doppler residual error estimation according to tracking data transmitted by the NCO and Doppler prediction results obtained in the direction of the sight of the satellite channels.
9. The receiver of claim 8,
the filter is also used for filtering and denoising the Doppler residual estimation, the tracking error of the carrier phase and the tracking error of the Doppler frequency to obtain a carrier phase and Doppler frequency tracking result;
the NCO is used for generating a recurrent carrier signal according to the latest tracking result.
10. The receiver of claim 9 wherein the filter comprises a system model and an observation model of carrier tracking, wherein the system noise of the carrier signal is determined by crystal phase noise and dynamic random walk-around noise, wherein the observed noise variance of the phase detector and the frequency detector output is determined by signal-to-carrier-to-noise ratio, wherein the observed noise variance of the doppler residual is determined by an estimate of the clock drift output by the position solution module, and wherein the filter gain is determined based on the system noise and the observation model.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010302731.7A CN111458730B (en) | 2020-04-17 | 2020-04-17 | GNSS carrier tracking method based on Doppler residual estimation and receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010302731.7A CN111458730B (en) | 2020-04-17 | 2020-04-17 | GNSS carrier tracking method based on Doppler residual estimation and receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111458730A CN111458730A (en) | 2020-07-28 |
| CN111458730B true CN111458730B (en) | 2021-02-02 |
Family
ID=71682547
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010302731.7A Active CN111458730B (en) | 2020-04-17 | 2020-04-17 | GNSS carrier tracking method based on Doppler residual estimation and receiver |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111458730B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111983654B (en) * | 2020-08-24 | 2021-03-19 | 中国矿业大学 | Method for constructing ionosphere phase scintillation factor in arctic region based on GNSS |
| CN114650107B (en) * | 2020-12-17 | 2024-05-28 | 北京合众思壮科技股份有限公司 | Signal quality monitoring method and device, electronic equipment and storage medium |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101738624A (en) * | 2009-12-15 | 2010-06-16 | 和芯星通科技(北京)有限公司 | Signal acquisition system and method for satellite navigation receiver |
| JP5854718B2 (en) * | 2011-09-08 | 2016-02-09 | 日本無線株式会社 | Satellite signal receiver |
| CN107255822A (en) * | 2017-06-01 | 2017-10-17 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | GNSS receiver modulated parameter estimating method under multi-path environment |
| CN109407126A (en) * | 2018-10-15 | 2019-03-01 | 北极星云空间技术股份有限公司 | A kind of method that multimode rake receiver alignment by union resolves |
| CN110068843A (en) * | 2019-05-06 | 2019-07-30 | 北京六分科技有限公司 | Satellite positioning receiver, method and apparatus |
| CN110161546A (en) * | 2019-05-23 | 2019-08-23 | 杭州中科微电子有限公司 | A kind of satellite orientation device and method using iteration Weighted Fuzzy degree function method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103592662B (en) * | 2013-11-29 | 2016-09-28 | 中国航天科工信息技术研究院 | The carrier wave tracing method of a kind of gps signal receiver and loop |
| CN106646548B (en) * | 2016-10-27 | 2020-03-10 | 易通共享技术(广州)有限公司 | Multimode ultra-fast and low-power-consumption positioning receiver system and method |
| CN106707306B (en) * | 2016-12-09 | 2019-04-02 | 北京无线电计量测试研究所 | A kind of GNSS receiver carrier-phase measurement error-detecting method |
| CN107728172A (en) * | 2017-09-08 | 2018-02-23 | 南京理工大学 | A kind of spaceborne receiver of the Big Dipper/GPS dual-mode and its navigation locating method |
| CN208270770U (en) * | 2017-11-21 | 2018-12-21 | 嘉兴佳利电子有限公司 | A kind of intelligence GNSS track following instrument |
-
2020
- 2020-04-17 CN CN202010302731.7A patent/CN111458730B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101738624A (en) * | 2009-12-15 | 2010-06-16 | 和芯星通科技(北京)有限公司 | Signal acquisition system and method for satellite navigation receiver |
| JP5854718B2 (en) * | 2011-09-08 | 2016-02-09 | 日本無線株式会社 | Satellite signal receiver |
| CN107255822A (en) * | 2017-06-01 | 2017-10-17 | 西南电子技术研究所（中国电子科技集团公司第十研究所） | GNSS receiver modulated parameter estimating method under multi-path environment |
| CN109407126A (en) * | 2018-10-15 | 2019-03-01 | 北极星云空间技术股份有限公司 | A kind of method that multimode rake receiver alignment by union resolves |
| CN110068843A (en) * | 2019-05-06 | 2019-07-30 | 北京六分科技有限公司 | Satellite positioning receiver, method and apparatus |
| CN110161546A (en) * | 2019-05-23 | 2019-08-23 | 杭州中科微电子有限公司 | A kind of satellite orientation device and method using iteration Weighted Fuzzy degree function method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111458730A (en) | 2020-07-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8456353B2 (en) | Method and system for determining clock corrections | |
| US7692577B2 (en) | Method and apparatus for geolocation determination | |
| CN104076371B (en) | Utilize the internet focus positioning of satellite system | |
| CN111158022B (en) | Receiver tracking method based on low-earth-orbit satellite | |
| US7986266B2 (en) | Method and system for selecting optimal satellites in view | |
| KR101199048B1 (en) | Precise absolute time transfer from a satellite system | |
| US7463979B2 (en) | Method and apparatus for initializing an approximate position in a GPS receiver | |
| CN111158023B (en) | Receiver terminal anti-interference method based on low-earth orbit satellite | |
| US7446703B2 (en) | Apparatus and method for receiving GPS signals in a mobile terminal | |
| FI110290B (en) | A method for determining the phase of information and an electronic device | |
| US20070236387A1 (en) | Method of optimization of processing of location data in the presence of a plurality of satellite positioning constellations | |
| WO2003092319A1 (en) | Position determination for a wireless terminal in a hybrid position determination system | |
| CN111458730B (en) | GNSS carrier tracking method based on Doppler residual estimation and receiver | |
| US6154173A (en) | Method and apparatus for processing multipath reflection effects in timing systems | |
| CN114594500B (en) | GNSS/LEO fusion positioning receiver system and positioning method | |
| US6970785B2 (en) | Device for a mobile terminal for determining position by filtering integrity data from an augmentation device | |
| WO2010080675A2 (en) | Method and system for selecting optimal satellites for a-gps location of handsets in wireless networks | |
| JP2002350526A (en) | Method of determining information element boundary, system and electronic apparatus | |
| Soloviev et al. | Decoding navigation data messages from weak GPS signals | |
| US20050147191A1 (en) | Extended frequency error correction in a wireless communication receiver | |
| CN114397681B (en) | GNSS receiver carrier tracking method based on robust prediction variable structure filtering | |
| CN114740500A (en) | Satellite navigation receiver multi-address interference detection processing method | |
| CN117250649A (en) | Distance and Doppler combined quick positioning method based on single low-orbit satellite | |
| Zhu et al. | Radio Frequency Compatibility Assessment of COMPASS New Signals |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Unit E2-601, Artificial Intelligence Industrial Park, No. 88, Jinjihu Avenue, Suzhou Industrial Park, China (Jiangsu) Pilot Free Trade Zone, Suzhou City, Jiangsu Province, 215000 Patentee after: Suzhou Tianshuo Navigation Technology Co.,Ltd. Address before: Room 305, building 1, 1228 Jinhu Road, China (Shanghai) pilot Free Trade Zone, Pudong New Area, Shanghai, 201206 Patentee before: Shanghai Jingrong Network Technology Co.,Ltd. |
|
| CP03 | Change of name, title or address |