CN102981171A - Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver - Google Patents
Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver Download PDFInfo
- Publication number
- CN102981171A CN102981171A CN2012104337049A CN201210433704A CN102981171A CN 102981171 A CN102981171 A CN 102981171A CN 2012104337049 A CN2012104337049 A CN 2012104337049A CN 201210433704 A CN201210433704 A CN 201210433704A CN 102981171 A CN102981171 A CN 102981171A
- Authority
- CN
- China
- Prior art keywords
- doppler frequency
- satellite
- location
- lot
- gps
- 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.)
- Granted
Links
Images
Landscapes
- Position Fixing By Use Of Radio Waves (AREA)
Abstract
The invention discloses a global position system (GPS) satellite carrier frequency detection method, a detection device and a GPS receiver. The GPS satellite carrier frequency detection method is a method used for detecting whether a detection value of a carrier frequency of a GPS satellite which does not participate in locating services. The method includes a first step of calculating the movement velocity of the GPS receiver through utilization of location information and Doppler information of a satellite which is chosen to be used for GPS positioning, and obtaining a Doppler frequency calculation value of the carrier frequency of the GPS satellite which does not participate in the locating services, a second step of comparing the Doppler frequency calculation value of the carrier frequency of the GPS satellite which does not participate in the locating services and a Doppler frequency measured value of a digital carrier frequency locked loop of the GPS satellite, and a third step of ensuring that the Doppler frequency measured value of the digital carrier frequency locked loop of the GPS satellite which does not participate in the locating services is wrong when the Doppler frequency calculation value is inconsistent with the Doppler frequency measured value.
Description
The application is that the application number submitted on June 30th, 2009 is 200910158460.6, denomination of invention is divided an application for the application for a patent for invention of " the carrier frequency detection method of gps satellite and device and GPS receiver ".
Technical field
Present invention relates in general to a kind of GPS(GPS) technology, especially relate to the technology for detection of the carrier frequency of gps satellite.
Background technology
As shown in Figure 1, general GPS receiver mainly is comprised of antenna 10, prime amplifier 20, radio frequency-intermediate frequency (RF/IF) transducer 30, modulus (A/D) transducer 40, digital baseband processor 50, navigating processor 60 and control display unit 70.The radiofrequency signal (RF) of gps satellite emission receives by antenna 10, and by passive bandpass filter (not shown) filtering, to reduce to be with outer Radio frequency interference (RFI).Then, radiofrequency signal is amplified in advance by prime amplifier 20, and down-converted to intermediate frequency (IF) signal by RF/IF transducer 30, use 40 pairs of IF signal samplings of modulus (A/D) transducer and digitizing, the digital medium-frequency signal that obtains (being also referred to as digital baseband signal) is sent into digital baseband processor (DBP) 50 and is processed again.Digital baseband processor 50 is mainly finished following functions: search of satellite, traction and tracking satellite; The navigation message data-signal is carried out despreading, demodulate the navigation message data; Carrying out pseudo range measurement, carrier phase measurement and Doppler frequency deviation measures.For realizing despreading, the demodulation of spread-spectrum signal, comprise digital pseudo-code delay lock loop (DDLL), digital carrier phaselocked loop (DPLL) and digital carrier FLL (DFLL) among the DBP.The satellite information that obtains after the intermediate frequency data demodulation is sent to navigating processor 60 and positions calculating, determines user's Position, Velocity and Time (PVT) information.As can see from Figure 1, navigating processor 60 comprises: select star device 610 to be used for selecting corresponding satellite information to process, speed calculating apparatus 620 and position and clock resolver 630 are used for determining PVT information, and comprise after-treatment device 640.At last, PVT information is intuitively shown on the screen of GPS receiver by control display unit 70.
In the processing procedure of GPS receiver, pseudo-code delay lock loop, digital carrier phaselocked loop and digital carrier FLL are vital to the performance impact of receiver.The pseudo-code delay lock loop is used for measuring the time of reception of pseudo-code, and the value of this time of reception has directly determined the measuring accuracy of pseudorange.The digital carrier phaselocked loop is used for carrier phase measurement, and the digital carrier FLL is used for the Doppler frequency deviation of carrier wave to be measured, and these two measured values are used for the carrier phase of baseband signal and peeling off of Doppler frequency.If deviation appears in carrier phase-locked loop, carrier wave FLL and pseudo-code delay lock loop, then can directly cause the pseudo range measurement of satellite inaccurate, thereby so that deviation appears in the final user PVT information of calculating, this deviation is unacceptable many times.
Because carrier phase-locked loop, FLL and pseudo-code delay lock loop are to the decisive role of GPS receiver performance, this three's design also is vital.Because the reaction velocity of carrier wave FLL is fast than the pseudo-code delay lock loop, be used for revising the pseudo-code delay lock loop so all can consider the Doppler shift value that the carrier wave FLL is obtained when generally designing, if skew appears in the tracking frequencies of carrier wave FLL, then can cause the skew of pseudo-code delay lock loop.Fig. 2 shows over time synoptic diagram of carrier doppler frequency shift (FS) that static receiver carrier phase-locked loop under normal circumstances follows the tracks of.As can be seen from Figure 2, under normal circumstances, the carrier doppler frequency deviation Changing Pattern that DFLL follows the tracks of is very level and smooth reduce or increase.
When deviation appearred in the carrier doppler frequency deviation of DFLL tracking, situation was from shown in Figure 2 different.Fig. 3 shows when FLL and follows the tracks of when unusual the carrier doppler frequency of output.The problem that skew appears in Doppler frequency all occurred following the tracks of as can be seen from Figure 3 in 500s, 1000s and 1500s position, side-play amount is about 200Hz-400Hz, and this has directly caused positioning result and more than the actual position deviation 100m.Its reason mainly is in the weak signal situation, because the impact of noise and multipath is difficult to guarantee the long-term stability of FLL tracking, when frequency of occurrences deviation, uses carrier lock to detect and can't reflect also whether tracking is normal.
Summary of the invention
An object of the present invention is, propose a kind of method and apparatus, unusual frequency deviation occurs by the carrier wave that uses the method and device can effectively detect satellite.
Another object of the present invention is, proposes a kind of method and apparatus, can remotivate rapidly based on the testing result to the frequency shift (FS) of the carrier wave of gps satellite catching satellite that the unusual frequency deviation of carrier wave occurs by using the method and device.
Another object of the present invention is, proposes a kind of method and apparatus, can be based on the testing result of the frequency shift (FS) of the carrier wave of gps satellite being avoided the select of satellite with being judged as carrier wave and occurring unusual frequency deviation be used for the location by using the method and device.
Whether another object of the present invention is, proposes a kind of method and apparatus, correct by using the method and device can detect the carrier frequency detected value of the gps satellite that has neither part nor lot in the location.
A further object of the present invention is to propose a kind of GPS receiver that uses at least a said method and/or device.
According to an aspect of the present invention, a kind of method of Doppler shift of the carrier frequency for detection of gps satellite has been proposed, comprise: a. calculates the carrier frequency Doppler frequency changing value in the given time of every satellite for every satellite in all satellites on following the tracks of; The mean value of the Doppler frequency changing value of the carrier frequency of all satellites on b. calculating is followed the tracks of; If c. the Doppler frequency changing value of the carrier frequency of in all satellites in the described tracking or multi-satellite is both greater than the mean value of described Doppler frequency changing value and the product of setting weight, and again greater than setting threshold, judge that then unusual frequency deviation appears in the carrier wave of described or multi-satellite.
Correspondingly, the present invention has also proposed a kind of Doppler shift pick-up unit of the carrier frequency for detection of gps satellite, comprise: the frequency offset computations device, it is designed for for every satellite in all satellites on following the tracks of, calculate the carrier frequency Doppler frequency changing value in the given time of every satellite, and the mean value of the Doppler frequency changing value of the carrier frequency of all satellites in the calculating tracking; Frequency is with inclined to one side pick-up unit, if wherein the Doppler frequency changing value of the carrier frequency of in all satellites in the described tracking or multi-satellite is both greater than the mean value of described Doppler frequency changing value and the product of setting weight, and again greater than setting threshold, then described frequency judges that with inclined to one side pick-up unit unusual frequency deviation appears in the carrier wave of described or multi-satellite.
According to another aspect of the present invention, in the method for the Doppler shift of above-mentioned carrier frequency for detection of gps satellite, described step c further comprises: when the Doppler frequency changing value of the carrier frequency of described or multi-satellite both greater than the mean value of described Doppler frequency changing value and the product of the first weight, and during again greater than first threshold, unusual frequency deviation appears in the carrier wave of judging described one or multi-satellite, and described method further comprises: d. excites the recapture that occurs described or the multi-satellite of unusual frequency deviation to being judged as carrier wave.
Correspondingly, the present invention has also proposed a kind of GPS receiver, comprise digital baseband processor and navigating processor, wherein said navigating processor comprises above-mentioned Doppler shift pick-up unit, wherein when described Doppler shift pick-up unit judges that unusual frequency deviation appears in the carrier wave of or multi-satellite, described Doppler shift pick-up unit notice digital baseband processor excites the recapture that occurs described or the multi-satellite of unusual frequency deviation to being judged as carrier wave.
According to another aspect of the present invention, in the method for the Doppler shift of above-mentioned carrier frequency for detection of gps satellite, described step c further comprises: when the Doppler frequency changing value of the carrier frequency of described or multi-satellite both greater than the mean value of described Doppler frequency changing value and the product of the second weight, and during again greater than Second Threshold, unusual frequency deviation appears in the carrier wave of judging described one or multi-satellite, and described method further comprises: e. will not be judged as described or the multi-satellite that unusual frequency deviation appears in carrier wave and select to be used for the location.
Correspondingly, the present invention has also proposed a kind of GPS receiver, comprise digital baseband processor and navigating processor, wherein said navigating processor comprises above-mentioned Doppler shift pick-up unit and the star device that selects that is used for selecting star, wherein: when described Doppler shift pick-up unit judges that unusual frequency deviation appears in the carrier wave of or multi-satellite, described Doppler shift pick-up unit notice select star device will be not described one or multi-satellite select to be used for locating.
According to a further aspect of the invention, whether the carrier frequency detected value that has proposed a kind of gps satellite for detection of having neither part nor lot in the location correct method, comprise: a. utilizes positional information and the doppler information of the satellite that is selected for the GPS location, calculate the movement velocity of GPS receiver, and obtain the Doppler frequency calculating value of the carrier frequency of the described gps satellite that has neither part nor lot in the location by the Doppler frequency deviation computing formula; B. the described Doppler frequency calculating value of the carrier frequency of the described gps satellite that has neither part nor lot in the location and the digital carrier FLL doppler frequency measurement value of this gps satellite are compared; And c. determines that the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong when described Doppler frequency calculating value and described doppler frequency measurement value are inconsistent.
Correspondingly, the present invention has also proposed a kind of doppler frequency measurement value detection device, comprise: frequency offset calculation device and frequency deviation Difference test device, described frequency offset calculation device is used for utilizing positional information and the doppler information of the satellite that is selected for the GPS location, calculate the movement velocity of GPS receiver, and obtain the described Doppler frequency calculating value that has neither part nor lot in the gps satellite of location by the Doppler frequency deviation computing formula; Described frequency deviation Difference test device is used for the described Doppler frequency calculating value of the described gps satellite that has neither part nor lot in the location and the digital carrier FLL doppler frequency measurement value of this gps satellite are compared, and when described Doppler frequency calculating value and described doppler frequency measurement value are inconsistent, judge that the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong.
Correspondingly, the present invention has also proposed a kind of GPS receiver, comprise digital baseband processor and navigating processor, wherein said navigating processor comprises above-mentioned doppler frequency measurement value detection device, wherein when described doppler frequency measurement value detection device judged that the digital carrier FLL doppler frequency measurement value of the gps satellite that has neither part nor lot in the location is wrong, described doppler frequency measurement value detection device notice digital baseband processor excited the recapture that this is had neither part nor lot in the gps satellite of location.
Use can determine from the multi-satellite of following the tracks of effectively according to method and/or the device of the Doppler shift of the carrier frequency for detection of gps satellite of the present invention whether the DFLL of the carrier wave of certain satellite goes wrong.
In addition, in said method according to the present invention and corresponding GPS receiver, can excite recapture and tracking to the satellite that unusual frequency deviation appears in carrier wave based on testing result, so that a normal satellite number of following the tracks of and the satellite number that can be used for locating improve a lot when not using according to detection method of the present invention, for example can be with a satellite number increase about 20% of normally following the tracks of.
In addition, in said method according to the present invention and corresponding GPS receiver, be not used for the location owing to will not be judged as the select of satellite that unusual frequency deviation appears in carrier wave, the select of satellite that therefore can avoid unusual frequency deviation carrier wave being occurred is used for the location, thereby has improved the bearing accuracy of GPS receiver.
In addition, utilization is according to the carrier frequency detected value of the gps satellite for detection of having neither part nor lot in the location of the present invention correct method and corresponding doppler frequency measurement value detection device and GPS receiver whether, can effectively avoid the satellite of the vicious doppler frequency measurement value of tool is selected into for location Calculation, thereby improve the bearing accuracy of GPS receiver under the weak signal.
Description of drawings
The present invention can by with reference to hereinafter by reference to the accompanying drawings given description be better understood, wherein in institute's drawings attached, used same or analogous Reference numeral to represent identical or similar parts.Described accompanying drawing comprises in this manual and forms the part of this instructions together with following detailed description, and is used for further illustrating the preferred embodiments of the present invention and explains principle and advantage of the present invention.In the accompanying drawings:
Fig. 1 shows the structural drawing of GPS receiver of the prior art;
Fig. 2 shows the under normal circumstances carrier doppler frequency deviation variation diagram of DFLL tracking;
Fig. 3 shows the carrier doppler frequency that FLL is followed the tracks of unusual time output;
That Fig. 4 shows is according to an embodiment of the invention, for detection of the process flow diagram of the method for the Doppler shift of the carrier wave of gps satellite;
That Fig. 5 shows is according to an embodiment of the invention, for detection of the Doppler shift of the carrier wave of gps satellite and excite as required the process flow diagram of the method for satellite recapture;
Fig. 6 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 5;
That Fig. 7 shows is according to an embodiment of the invention, for detection of the Doppler shift of the carrier wave of gps satellite and do not select as required the process flow diagram of the method that satellite is used to locate;
Fig. 8 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 7;
That Fig. 9 shows is according to an embodiment of the invention, for detection of the DFLL doppler frequency measurement value process flow diagram of correct method whether;
Figure 10 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 9; And
Figure 11 shows an example of the frequency deviation testing result that obtains by the method for using as shown in Figure 5.
Embodiment
In connection with accompanying drawing example embodiment of the present invention is described hereinafter.For clarity and conciseness, all features of actual embodiment are not described in instructions.Yet, should understand, in the process of any this practical embodiments of exploitation, must make a lot of decisions specific to embodiment, in order to realize developer's objectives, and these decisions may change to some extent along with the difference of embodiment.In addition, might be very complicated and time-consuming although will also be appreciated that development, concerning the those skilled in the art that have benefited from present disclosure, this development only is routine task.
At this, what also need to illustrate a bit is, for fear of having blured the present invention because of unnecessary details, only show in the accompanying drawings with according to the closely-related apparatus structure of the solution of the present invention, and omitted other details little with relation of the present invention.
As start mentioned because in the weak signal situation, the impact of noise and multipath is difficult to the long-term stability that guarantees that FLL is followed the tracks of, so skew appears in the carrier frequency of satellite easily.
According to the characteristics of motion of gps satellite and the characteristics of motion of receiver, the computing formula of the Doppler frequency size of carrier wave is disclosed in " GPS principle and application " (second edition) that the people such as Elliott D.Kaplan show the 42nd page:
Wherein, f
TIt is the frequency of satellite emission signal;
V
rIt is satellite and user's relative velocity vector;
A is the rectilinear direction unit vector of pointing to the user along satellite;
C is velocity of propagation;
Dot product V
rA represents that the relative velocity vector is along the radial vector of the line of satellite.
Can learn by following formula, the variation size of Doppler frequency can be estimated under the truth, peak acceleration such as known receiver is that 0.5g(g is acceleration of gravity), then can estimate the maximal increment of Doppler frequency within the unit interval (when this acceleration is on the unit vector direction of the rectilinear direction of pointing to the user along satellite, obtaining) and be:
Because when receiver has this acceleration, larger variation all can occur in the multi-satellite carrier doppler frequency of following the tracks of, and when certain only has 1-2 satellite carrier Doppler frequency of tracking that larger variation occurs constantly, can think that then the DFLL that follows the tracks of this satellite carrier goes wrong.Based on this thinking, the present invention proposes a kind of method of Doppler shift of the carrier frequency for detection of gps satellite, wherein, calculate the DFLL carrier doppler frequency shift (FS) variable quantity within a certain period of time of the satellite on following the tracks of, if variable quantity meets some requirements, think that then the carrier wave of the satellite in the described tracking has problem, unusual frequency deviation namely occurred.
That Fig. 4 shows is according to an embodiment of the invention, for detection of the process flow diagram of the method for the Doppler shift of the carrier frequency of gps satellite, comprising following steps:
S410: for every satellite in all N satellite on following the tracks of, calculate the carrier frequency Doppler frequency changing value Δ f in the given time of every satellite
Di(i=1,2 ... N);
S420: the mean value that calculates the Doppler frequency changing value of all satellites on following the tracks of according to following equation:
S430: if the Doppler frequency changing value of or multi-satellite is arranged in all satellites of following the tracks of
W is the setting weight, and Δ f
DiGreater than setting threshold THRESH1, judge that then unusual frequency deviation appears in this of tracking or the carrier wave of multi-satellite.Wherein weight w and setting threshold THRESH1 can determine by emulation.For example, a kind of Weight Determination is: in the data that the unusual frequency deviation in many places is arranged, detect by setting different weighted values, then add up the correct probability of testing result, thereby obtain suitable weighted value.General this weighted value is set between the 1.5-3.0.
Especially, wherein calculate the Doppler frequency changing value Δ f of every satellite
dStep comprise: for described every satellite, with the Doppler frequency value f of the current time t of digital carrier FLL
Di(t) deduct (for example, supposing to represent with m unit interval) Doppler frequency value f before of the described schedule time
Di(t-m), obtain the Doppler frequency changing value Δ f of respective satellite
Di=f
Di(t)-f
Di(t-m).Especially, wherein m is chosen as between 10 to 20 usually.For example, the top unit interval can be 500ms.
Especially faster in the situation, by utilizing said method, can obtain good testing result at the DFLL Doppler shift.
Corresponding to the method for setting forth according to Fig. 4, according to one embodiment of present invention, a kind of Doppler shift pick-up unit of the carrier frequency for detection of gps satellite has been proposed.This Doppler shift pick-up unit comprises: the frequency offset computations device, it is designed for the step S410 of execution said method and the processing among the S420, namely, calculate the carrier frequency Doppler frequency changing value in the given time of each satellite on following the tracks of, and the mean value of the Doppler frequency variation of the carrier frequency of all satellites of following the tracks of; And frequency is with inclined to one side pick-up unit, it is designed for the processing among the step S430 that carries out said method, namely, detect the Doppler frequency changing value of the carrier frequency of each satellite of following the tracks of based on the result of calculation of frequency offset computations device, judge whereby whether the corresponding satellite carrier of following the tracks of unusual frequency deviation occurs.At this, do not draw separately in the accompanying drawings the synoptic diagram of Doppler shift pick-up unit, its structure can be referring to for example also being described in more detail hereinafter with 600 parts that represent among Fig. 6.
By method recited above and Doppler shift pick-up unit, can determine from the multi-satellite of following the tracks of effectively whether the DFLL of the carrier wave of certain satellite goes wrong.
Based on the method described in Fig. 4, can in the situation of the unusual frequency deviation of Doppler of the carrier frequency that detects gps satellite, take corresponding countermeasure for the different application situation.
Fig. 5 show according to another embodiment of the present invention for detection of Doppler shift and excite as required the process flow diagram of method of recapture that the satellite of unusual frequency deviation carrier wave occurred.
In method shown in Figure 5, step S510 to S530 corresponds respectively to the step S410 to S430 shown in Fig. 4, therefore, and for just no longer having described in detail at this for purpose of brevity of instructions.The difference of method shown in Figure 5 and method shown in Figure 4 is, has increased step S540: excite the recapture that occurs the satellite of unusual frequency deviation to being judged as carrier wave.
Fig. 6 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 5.As can be seen from Figure 6, in navigating processor 60, comprise Doppler shift pick-up unit 600 mentioned above, and this Doppler shift pick-up unit 600 comprises that frequency offset computations device 650 and frequency are with inclined to one side pick-up unit 660.The data of digital baseband processor 50 outputs are imported in the frequency offset computations device 650.In frequency offset computations device 650, carry out in conjunction with the step S510 of the described method of Fig. 5 and the processing among the S520, namely, calculate the carrier frequency Doppler frequency changing value in the given time of each satellite on following the tracks of, and the mean value of the Doppler frequency variation of the carrier frequency of all satellites of following the tracks of.In frequency with the processing among the step S530 that carries out said method in the inclined to one side pick-up unit 660, namely, based on the Doppler frequency changing value of the satellite in each tracking of result of calculation detection of frequency offset computations device 650, judge whereby whether the carrier wave of the respective satellite of following the tracks of unusual frequency deviation occurs.If determine that certain DFLL loop tracks has problem, then Doppler shift pick-up unit 600 notice digital baseband processors 50 excite the recapture that occurs the satellite of unusual frequency deviation to being judged as carrier wave.
By this for detection of Doppler shift and excite as required method and the corresponding GPS receiver of recapture that the satellite of unusual frequency deviation carrier wave occurred, can determine that the DFLL for the carrier wave of certain satellite goes wrong (unusual frequency deviation appears in the carrier wave of namely judging this satellite) afterwards, reduces because the positioning error that this problem is introduced by exciting the recapture to this satellite.
In addition, in selecting the star process, select to be used for the location for fear of DFLL being followed the tracks of the satellite information make mistakes larger, can in selecting star device, add and select the star strategy with reference to the Doppler shift amount.Therefore, the invention allows for a kind of method of selecting satellite, the method is also based on the method for setting forth according to Fig. 4.Fig. 7 shows this detection Doppler shift and does not select as required carrier frequency the process flow diagram of the method for the unusual satellite of skew to occur.
In method shown in Figure 7, step S710 to S730 corresponds respectively to the step S410 to S430 shown in Fig. 4, be to have increased step S740 with the difference of method shown in Figure 4, wherein will be detected the respective satellite that unusual frequency deviation appears in carrier wave and select to be used for the location.
Fig. 8 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 7.As can be seen from Figure 8, in navigating processor 60, increased equally mentioned above, comprise that frequency offset computations device 650 and frequency are with the Doppler shift pick-up unit 600 of inclined to one side pick-up unit 660.Wherein Doppler shift pick-up unit 600 carry out with in identical function set forth in fig. 6.The difference of GPS receiver shown in Figure 8 and GPS receiver shown in Figure 6 is that if determine that certain FLL loop tracks has problem, then Doppler shift pick-up unit 600 notices select star device 610 corresponding the select of satellite not to be used for the location.
By method and the corresponding GPS receiver of this selection satellite, can avoid effectively that FLL is followed the tracks of the satellite information of makeing mistakes larger and select to be used for the location, thereby guarantee the bearing accuracy of GPS.
Certainly also possiblely be, combine by Fig. 5 method of setting forth and the method for setting forth by Fig. 7 top, namely obtain at first respectively the mean value of the Doppler frequency changing value of the Doppler frequency changing value of each satellite of following the tracks of and all satellites; Then judge whether certain satellite carrier of following the tracks of unusual frequency deviation occurs; Occur in the situation of unusual frequency deviation detecting satellite carrier, excite recapture and/or avoid respective satellite is selected to be used for the location.Correspondingly, in the GPS receiver, also can comprise simultaneously from Doppler shift pick-up unit 600 to digital baseband processor 50 and to the signal stream that selects star device 610.Although do not provide corresponding method flow diagram and/or structure drawing of device at this, those skilled in the art can draw out corresponding method flow diagram and/or structure drawing of device according to foregoing description at an easy rate.
In addition, need to prove that weight and threshold value in the weight in the method flow diagram shown in Figure 5 and threshold value and the method flow diagram shown in Figure 7 can be the same or different.
For the satellite that has neither part nor lot in the location, according to another embodiment of the present invention, whether the carrier frequency detected value that has also proposed a kind of gps satellite for detection of having neither part nor lot in the location correct method.Fig. 9 shows the process flow diagram of the method, comprising following steps:
S910: positional information and the doppler information of the satellite by being selected for GPS location, calculate the movement velocity of GPS receiver, in the correct situation of the satellite information, the doppler information that participate in the location, the receiver movement velocity of then calculating this moment is correct, thereby can obtain having neither part nor lot in the Doppler frequency calculating value of carrier frequency of the satellite of location by following Doppler frequency deviation computing formula:
S920: will have neither part nor lot in the Doppler frequency calculating value of carrier frequency of satellite of location and the DFLL doppler frequency measurement value of this satellite and compare;
S930: when Doppler frequency calculating value and doppler frequency measurement value are inconsistent, guaranteeing to conclude that the DFLL doppler frequency measurement value of this satellite is wrong under the correct condition of this satellite position calculation.
Corresponding to the method for setting forth according to Fig. 9, according to one embodiment of present invention, whether correct doppler frequency measurement value detection device of a kind of gps satellite carrier frequency detected value for detection of having neither part nor lot in the location has been proposed.This doppler frequency measurement value detection device comprises: frequency offset calculation device and frequency deviation Difference test device.Processing in the frequency offset calculation device among the step S910 of execution said method, namely, positional information and the doppler information of the satellite by being selected for GPS location, calculate the movement velocity of GPS receiver, and calculate the Doppler frequency calculating value of the carrier frequency of the satellite that has neither part nor lot in the location by described Doppler frequency deviation computing formula.Participate in the correct situation of the satellite information of location and doppler information in hypothesis, this Doppler frequency calculating value is correct.Subsequently, in frequency deviation Difference test device, carry out the step S920 of said method and the processing among the S930, namely, compare having neither part nor lot in the Doppler frequency calculating value of position location satellite and the DFLL doppler frequency measurement value of this satellite, judge whereby whether the DFLL doppler frequency measurement value of respective satellite is correct.If this doppler frequency measurement value is incorrect, illustrate that then this satellite can not be used to location Calculation, thereby this doppler frequency measurement value detection device can notify digital baseband processor to excite the recapture that this is had neither part nor lot in the gps satellite of location.At this, do not draw separately in the accompanying drawings the synoptic diagram of doppler frequency measurement value detection device, can referring among Figure 10 for example with 601 parts that represent.
Figure 10 shows the structural drawing of the GPS receiver that wherein can carry out method shown in Figure 9.As can be seen from Figure 10, in navigating processor, increased doppler frequency measurement value detection device 601 mentioned above, that comprise frequency offset calculation device 680 and frequency deviation Difference test device 690.When the doppler frequency measurement value of doppler frequency measurement value detection device 601 judgement respective satellite was incorrect, then doppler frequency measurement value detection device 601 notice digital baseband processors 50 excited the recapture that this is had neither part nor lot in the gps satellite of location.
Especially, wherein said frequency offset calculation device 680 is realized with software mode.
Whether the carrier frequency detected value by this gps satellite for detection of having neither part nor lot in the location correct method and corresponding doppler frequency measurement value detection device and GPS receiver, effectively avoided the satellite of the vicious DFLL doppler frequency measurement of tool value is selected into for location Calculation, thereby improved the bearing accuracy of GPS receiver.
In addition, according to still another embodiment of the invention, for the ease of improving the bearing accuracy of GPS receiver, also above method described in conjunction with Figure 5 and/or method described in conjunction with Figure 7 and method described in conjunction with Figure 9 can be made up.Namely on the one hand, obtain respectively the mean value of the Doppler frequency changing value of the Doppler frequency changing value of each satellite of following the tracks of and all satellites; Then judge whether certain satellite carrier of following the tracks of unusual frequency deviation occurs; Occur in the situation of unusual frequency deviation detecting satellite carrier, excite recapture and/or avoid respective satellite is selected to be used for the location; On the other hand, can compare having neither part nor lot in the Doppler frequency calculating value of position location satellite and the DFLL doppler frequency measurement value of this satellite, judge whereby whether the DFLL doppler frequency measurement value of respective satellite is correct.If this doppler frequency measurement value is incorrect, illustrates that then this satellite can not be used to location Calculation, and excite the recapture that this is had neither part nor lot in the gps satellite of location.Correspondingly, in the GPS receiver, can comprise simultaneously Doppler shift pick-up unit 600 and doppler frequency measurement value detection device 601 and corresponding signal stream.Although do not provide corresponding method flow diagram and/or structure drawing of device at this, those skilled in the art can draw out corresponding method flow diagram and/or structure drawing of device according to foregoing description at an easy rate.
In above-mentioned the whole bag of tricks, all can be with the carrier-to-noise ratio (CNR) of satellite as with reference to condition.For example, can in said method, increase following steps: judge that whether the CNR of relevant satellite to be detected is greater than predetermined threshold, when CNR is stronger, for example as CNR during more than or equal to predetermined threshold THRESH3, think that this satellite-signal is believable, and the DFLL Doppler shift is normal, the result of above-mentioned detection method is invalid, and in according to the method for Fig. 5, do not excite the recapture that occurs the satellite of unusual frequency deviation to being judged as carrier wave, and/or in according to the method for Fig. 7, do not affect and to be judged as described or the multi-satellite that unusual frequency deviation appears in carrier wave and to select to be used for the location, and/or in the method according to Fig. 9, the DFLL doppler frequency measurement value of determining respective satellite is correct and can be selected for the location; As CNR during less than predetermined threshold THRESH3, the result of above-mentioned detection method is effective, and can carry out corresponding operation or processing.Wherein threshold value THRESH3 can determine by emulation.
According to another embodiment, in the method for the Doppler shift of above-mentioned carrier frequency for detection of gps satellite and/or for detection of the carrier frequency detected value of the gps satellite that has neither part nor lot in the location whether in the correct method, in order to improve the reliability of detection, also proposed to get among the N detection method of M.Namely, in testing process, repeat for N time on the continuous time interval to detect, and testing result counted, if wherein M testing result judges that all unusual frequency deviation appears in the carrier wave of respective satellite at least, think that then the result of determination that unusual frequency deviation appears in the carrier wave of described or multi-satellite is effective, and/or M testing result judges that all the described DFLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong at least, thinks that then the result of determination of digital carrier FLL doppler frequency measurement value mistake of the described gps satellite that has neither part nor lot in the location is effective.Wherein, M and N are positive integer and M≤N.After operation like this, effectively reduced the probability of false detection of detection method.
After using the Doppler shift detection method, can effectively reduce Satellite Doppler Method and follow the tracks of and forbidden the pseudorange that causes inaccurate.The result's that Figure 10 has obtained in conjunction with the described the method according to this invention of Fig. 5 more than having provided and having used a exemplary, wherein hwfrq represents the carrier doppler frequency that DFLL follows the tracks of, swfrq represents the carrier doppler frequency by the calculating of receiver speed, in the drawings the Frequency generated followed the tracks of of DFLL skew, side-play amount is detected about 200Hz, excite thus the recapture that occurs the satellite of unusual frequency deviation frequency deviation to being judged as carrier wave, thereby so that a normal satellite number of following the tracks of and the normal tracking satellite number that can be used for locating be significantly improved when not using according to detection method of the present invention, and can improve significantly the bearing accuracy of GPS receiver under the weak signal.
At last, also need to prove, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thereby not only comprise those key elements so that comprise process, method, article or the equipment of a series of key elements, but also comprise other key elements of clearly not listing, or also be included as the intrinsic key element of this process, method, article or equipment.In addition, do not having in the situation of more restrictions, the key element that is limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment that comprises described key element and also have other identical element.
Although more than describe by reference to the accompanying drawings embodiments of the invention in detail, should be understood that embodiment described above just is used for explanation the present invention, and be not construed as limiting the invention.For a person skilled in the art, can make various changes and modifications above-mentioned embodiment and do not deviate from the spirit and scope of the invention.Therefore, scope of the present invention is only limited by appended claim and equivalents thereof.
Claims (8)
1. one kind for detection of the carrier frequency detected value of the gps satellite that has neither part nor lot in the location correct method whether, comprising:
A. utilize positional information and the doppler information of the satellite be selected for the GPS location, calculate the movement velocity of GPS receiver, and obtain the Doppler frequency calculating value of the carrier frequency of the described gps satellite that has neither part nor lot in the location by the Doppler frequency deviation computing formula;
B. the described Doppler frequency calculating value of the carrier frequency of the described gps satellite that has neither part nor lot in the location and the digital carrier FLL doppler frequency measurement value of this gps satellite are compared; And
C. when described Doppler frequency calculating value and described doppler frequency measurement value are inconsistent, determine that the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong.
2. method according to claim 1 also comprises:
Judge that whether the carrier-to-noise ratio CNR of the described gps satellite that has neither part nor lot in the location is greater than predetermined threshold; And
As the CNR of the described gps satellite that has neither part nor lot in the location during greater than this predetermined threshold, judge that the result of determination of digital carrier FLL doppler frequency measurement value mistake of the gps satellite that has neither part nor lot in the location is invalid.
3. method according to claim 1 and 2, also comprise: on continuous time interval, repeat described step a to step c N time, if judge at least that wherein the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong for M time, the result of determination of then judging the digital carrier FLL doppler frequency measurement value mistake of the described gps satellite that has neither part nor lot in the location is effective, wherein, M and N are positive integer and M≤N.
4. one kind for detection of the carrier frequency detected value of the gps satellite that has neither part nor lot in the location correct doppler frequency measurement value detection device (601) whether, comprising: frequency offset calculation device (680) and frequency deviation Difference test device (690),
Described frequency offset calculation device (680) is used for utilizing positional information and the doppler information of the satellite that is selected for the GPS location, calculate the movement velocity of GPS receiver, and obtain the described Doppler frequency calculating value that has neither part nor lot in the gps satellite of location by the Doppler frequency deviation computing formula;
Described frequency deviation Difference test device (690) is used for the described Doppler frequency calculating value of the described gps satellite that has neither part nor lot in the location and the digital carrier FLL doppler frequency measurement value of this gps satellite are compared, and when described Doppler frequency calculating value and described doppler frequency measurement value are inconsistent, judge that the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong.
5. doppler frequency measurement value detection device according to claim 4 (601), wherein said frequency offset calculation device (680) are that software is realized.
6. a GPS (GPS) receiver comprises digital baseband processor (50) and navigating processor (60), and wherein said navigating processor (60) comprises according to claim 25 or 26 described doppler frequency measurement value detection devices (601),
Wherein when described doppler frequency measurement value detection device (601) judged that the digital carrier FLL doppler frequency measurement value of the gps satellite have neither part nor lot in the location is wrong, described doppler frequency measurement value detection device (601) notice digital baseband processor (50) excited the recapture that this is had neither part nor lot in the gps satellite of location.
7. GPS receiver according to claim 6, judge that wherein whether the carrier-to-noise ratio CNR of the described gps satellite that has neither part nor lot in the location is greater than predetermined threshold, as the CNR of the described gps satellite that has neither part nor lot in the location during greater than this predetermined threshold, do not affect navigating processor (60) the described satellite that has neither part nor lot in the location is used for location Calculation.
8. according to claim 6 or 7 described GPS receivers, wherein said doppler frequency measurement value detection device (601) repeats for N time on continuous time interval and calculates and judge, if judge at least that wherein the described digital carrier FLL doppler frequency measurement value that has neither part nor lot in the gps satellite of location is wrong for M time, the result of determination of then judging the digital carrier FLL doppler frequency measurement value mistake of the described gps satellite that has neither part nor lot in the location is effective, wherein, M and N are positive integer and M≤N.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210433704.9A CN102981171B (en) | 2009-06-30 | 2009-06-30 | Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210433704.9A CN102981171B (en) | 2009-06-30 | 2009-06-30 | Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009101584606A Division CN101937073B (en) | 2009-06-30 | 2009-06-30 | Method and device for detecting carrier frequency of GPS (Global Position System) satellites as well as GPS receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102981171A true CN102981171A (en) | 2013-03-20 |
| CN102981171B CN102981171B (en) | 2014-10-22 |
Family
ID=47855375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210433704.9A Active CN102981171B (en) | 2009-06-30 | 2009-06-30 | Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102981171B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107783166A (en) * | 2016-08-29 | 2018-03-09 | 千寻位置网络有限公司 | GPS velocity abnormality detection and the method and its system repaired |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5323164A (en) * | 1992-03-16 | 1994-06-21 | Pioneer Electronic Corporation | Satellite radio wave capturing method for a global positioning system (GPS) receiver |
| EP0527558B1 (en) * | 1991-07-09 | 1995-11-15 | Pioneer Electronic Corporation | GPS navigation system with local speed direction sensing and PDOP accuracy evaluation |
| US6931244B2 (en) * | 2000-07-27 | 2005-08-16 | Sanyo Electric Co., Ltd. | Radio equipment capable of real time change of antenna directivity and doppler frequency estimating circuit used for the radio equipment |
| CN101261318A (en) * | 2008-04-03 | 2008-09-10 | 北京航空航天大学 | High dynamic state spread-spectrum precise distance measurement receiving machine |
-
2009
- 2009-06-30 CN CN201210433704.9A patent/CN102981171B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0527558B1 (en) * | 1991-07-09 | 1995-11-15 | Pioneer Electronic Corporation | GPS navigation system with local speed direction sensing and PDOP accuracy evaluation |
| US5323164A (en) * | 1992-03-16 | 1994-06-21 | Pioneer Electronic Corporation | Satellite radio wave capturing method for a global positioning system (GPS) receiver |
| US6931244B2 (en) * | 2000-07-27 | 2005-08-16 | Sanyo Electric Co., Ltd. | Radio equipment capable of real time change of antenna directivity and doppler frequency estimating circuit used for the radio equipment |
| CN101261318A (en) * | 2008-04-03 | 2008-09-10 | 北京航空航天大学 | High dynamic state spread-spectrum precise distance measurement receiving machine |
Non-Patent Citations (1)
| Title |
|---|
| 王克锋等: "卫星通信多普勒频移计算方法研究", 《GNSS WORLD OF CHINA》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107783166A (en) * | 2016-08-29 | 2018-03-09 | 千寻位置网络有限公司 | GPS velocity abnormality detection and the method and its system repaired |
| CN107783166B (en) * | 2016-08-29 | 2020-10-16 | 千寻位置网络有限公司 | Method and system for detecting and repairing GPS (global positioning system) speed abnormity |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102981171B (en) | 2014-10-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101937073B (en) | Method and device for detecting carrier frequency of GPS (Global Position System) satellites as well as GPS receiver | |
| US7002516B2 (en) | Signal detector employing correlation analysis of non-uniform and disjoint sample segments | |
| JP4869022B2 (en) | Satellite signal tracking device and satellite signal receiver including the same | |
| US6388613B1 (en) | Portable GPS type distance/speed meter capable of selectively using doppler speed measuring method | |
| CN102426368B (en) | Losing lock detection method based on extended Kalman filter tracking loop in GPS receiver | |
| JP2009133702A (en) | Positioning device | |
| US20040116121A1 (en) | Compensating for frequency shift and timing shift in frequency and time tracking loops based on mobile unit velocity | |
| CN102426372A (en) | Carrier smoothing pseudo range method and device | |
| CN106291614A (en) | For the device of tracking satellite radio navigation signal in multi-path environment | |
| CN107450084A (en) | A kind of high sensitivity GNSS receiver and reacquisition implementation method based on CSAC | |
| CN102016622A (en) | Methods and apparatuses for processing satellite positioning system signals | |
| US7468691B2 (en) | Positioning device, positioning control method, and recording medium | |
| CN106918822A (en) | Calculate the GNSS receiver of the non-fuzzy discriminator for parsing subcarrier tracking fuzziness | |
| CN102176034A (en) | Satellite losing lock judging method of GPS (Global Positioning System) receiver | |
| US8031816B2 (en) | Method and apparatus for determining boundaries of information elements | |
| US6240366B1 (en) | GPS reception ratio detecting apparatus and portable type distance/speed meter capable of indicating GPS signal receiving condition | |
| US8953721B2 (en) | Cross correlation determination method and cross correlation determination device | |
| JP2008232771A (en) | Positioning device | |
| CN102981171B (en) | Global position system (GPS) satellite carrier frequency detection method and detection device and GPS receiver | |
| JP5519223B2 (en) | Satellite signal receiver | |
| JP2008209287A (en) | Satellite navigation receiver | |
| CN108627863B (en) | GNSS navigation message data demodulation method and device based on DFT and GNSS receiving terminal | |
| JP5679170B2 (en) | Satellite signal receiver | |
| JP2008089309A (en) | Positional information acquisition device, positional information acquisition method, and program for terminal device | |
| JP2002148326A (en) | Positioning method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20211129 Address after: 610041 floor 14, block a, Oriental hope building, No. 3, Gaopeng Avenue, high tech Zone, Chengdu, Sichuan Patentee after: Concave and Convex Electronics (Chengdu) Co.,Ltd. Address before: Room 1402, 289 Chunxiao Road, Zhangjiang hi tech park, Shanghai 201203 Patentee before: O2Micro Inc. |