CN114089618A - Method for observing and detecting atomic clock jump by using single pulsar - Google Patents
Method for observing and detecting atomic clock jump by using single pulsar Download PDFInfo
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Abstract
The invention provides a method for observing and detecting atomic clock jumps by utilizing a single pulsar, which is used for observing candidate pulsars in a timing manner, analyzing the timing to obtain the average phase deviation before and after the clock jumps, searching the ambiguity of the whole cycle of the pulsars caused by the clock jumps, calculating a given time jump value and finally correcting the system time. The invention takes the time after the interruption and restart as the reference to observe 1 pulsar, can realize the high-precision calculation of any clock jump value and provides support for the accurate recovery of the time signal after the interruption.
Description
Technical Field
The invention belongs to the technical field of time frequency, and relates to a method for detecting the jump size of an atomic time at any time.
Background
Atomic time is the current time reference keeping basis, and is generated by depending on an atomic clock. The atomic clock belongs to a precise instrument, the manufacturing process is complex, the requirement on the environment is high, the mass production is difficult, two clocks manufactured by the same manufacturer have great performance difference, and the service life of the common atomic clock is about 10 years. Atomic time is an integral time scale, has the characteristic of error accumulation, and influences the long-term stability of the atomic time. Atomic time is derived from an atomic clock, and is influenced by the manufacturing technology and the using environment of the atomic clock, so that a single clock has errors and can cause the interruption of the atomic time when a fault occurs. In order to avoid atomic time interruption, a timekeeping laboratory usually adopts a mode of combining a plurality of atomic clocks to keep time, utilizes comparison among atomic clocks in a timekeeping clock group to find and shield problematic atomic clocks in time, and adopts an atomic time algorithm to form a comprehensive atomic time scale, thereby reducing the influence of single clock error and improving the accuracy and reliability of atomic time.
Only the time keeps the laboratory by a set of atomic clock unitedly to watch the time, and most of the time user terminal only has 1 atomic clock, and for the time kept by 1 atomic clock, when the atomic clock is interrupted, when 1 new atomic clock is changed again or replaced, the time before and after interruption is discontinuous, the time can not be recovered independently by self, and the time needs to be compared and calibrated with an external time reference, so that the time before interruption can be kept continuous. The traditional method is to detect clock jumps by using another 1 continuously running atomic clock and compare the detected clock jumps based on 1pps of the atomic clock. However, 1pps is a periodic pulse signal and has no identifiability. The time jump value less than 1s can only be detected by comparing the reference atomic clock with 1pps, and the clock jump more than 1s has the problem of integer ambiguity. Thus, a 1pps atomic clock alone cannot detect a greater than 1s clock jump. The accurate calibration of time needs to be realized by combining external time code information.
Pulsar is a compact celestial body, has the characteristics of strong magnetic field and strong electric field, radiates stable periodic pulse signals, is known as the most stable 'natural clock' in the nature, considers that the long-term stability of millisecond pulsar can be comparable with that of an atomic clock, and can be applied to the time-frequency field. The pulsar clock has the advantages of long service life, high reliability, wide service range, difficult attack and the like. The pulsar rotation frequency can be measured very accurately by astronomical observation techniques, such as pulsar J0437-4715 by timing techniques, and the measured intrinsic rotation frequency value is 173.68794581218460089Hz, the error is 8.0E-14Hz, and the uncertainty (error/rotation frequency) of the rotation frequency is 4.6E-16. With the progress of observation technology, for example, FAST starts to observe pulsar in a conventional manner and build SKA in the future, the measurement precision of the intrinsic autorotation frequency of pulsar is continuously improved, and the application of pulsar is further accelerated.
The pulsar radiates stable periodic pulse signals, different pulsar radiates different contour characteristics, different rotation periods and identifiability. The periodic pulse signal of the radiation can be likened to a second pulse (1pps) of an atomic clock. According to the 1pps comparison technology similar to the traditional atomic clock, a clock jump value larger than the rotation period of the pulsar cannot be detected by using a single pulsar. In addition, the millisecond pulsar timing has high precision and is more suitable for detecting clock jumps, but the detectable clock jump value range is smaller due to the short period. Even if the clock skip value Δ t smaller than the period (P) is detected, it cannot be determined whether the actual clock skip value is Δ t or Δ t-P.
In 2020, Yunnan astronomical stage Li Shixuan et al, the method for detecting the clock jump of an atomic clock based on pulsar timing observation is provided, Bayesian statistical method is used for resolving the clock jump value of the atomic clock, and the algorithm is verified by using observed data of a Yunnan 40-meter antenna, wherein the resolving error of the clock jump value is 80 ns. But this method is only suitable for detecting clock jumps smaller than the period of the pulsar rotation. In the text, the clock jump is detected by using J0437-4715 timing observation data, the period of the source is 5.7ms, and when the clock jump value is greater than 5.7ms, the clock jump value is solved by using the source, the self-rotation integer ambiguity of the pulsar exists, and the actual clock jump value cannot be obtained.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a method for observing and detecting atomic clock hops by using a single pulsar, which can realize the calculation of any atomic clock hop value by observing 1 pulsar signal.
The technical scheme adopted by the invention for solving the technical problem comprises the following steps:
(1) taking the time provided by the atomic clock after restarting as a reference, and carrying out timing observation on the pulsar to obtain a pulsar data integral profile and a pulse arrival time TOA;
(2) the historical data before clock jump and the observed data after clock jump of pulsar are timed and analyzed uniformly to obtain the decimal part phi of the pulse phase jump value before and after time jump0；
(3) In the form of P.phi0Taking the pulsar period P as a step length as an initial value, and iteratively searching to obtain a clock jump correction value delta t;
(4) correcting the reference time by using the clock jump correction value delta t, and repeating the steps (1) to (3) to obtain an updated clock jump correction value delta t';
(5) and controlling the time frequency system by using the clock jump correction value delta t' to realize the time calibration of the reference system.
The pulsar selects a pulsar in a double-star system.
The step (3) utilizes a single-star clock jump resolving method to carry out iterative search to obtain a clock jump correction value delta t; the single-satellite clock-jump calculation method obtains a final timing residual error of a solar system planet calendar or a double-satellite orbit parameter caused by a reference time error, and then obtains a clock jump value according to trend fitting in the residual error.
The single-star clock jump resolving method comprises the following steps:
(1) fitting the whole time span data of the pulsar to obtain a rough decimal phase jump value phi before and after the clock jump0And then P.phi0The value is used as the initial value of the subsequent iteration fitting clock hop value;
(2) judging the initial clock jump value P phi0If it is the final clock jump value, if it is the clock jump value P.phi0After the reference clock is corrected, timing processing is carried out on the whole data, the timing analysis result meets the judgment condition A, and the initial clock hop value is the final clock hop fitting value;
the judgment condition A is that the relative deviation of timing residual values of the timing data before and after clock jump is smaller than a set threshold value;
if the initial value P.phi0If the clock jump value is not the final clock jump value, judging whether the clock jump value is positive or negative, adding 1 pulse cycle P on the initial value as a clock jump correction value, correcting the clock jump, and then timing and analyzing the whole timing data again; according to the judgment condition B, analyzing the direction k of clock jump value correction, and if the clock is correctWhen the residual value after the jump becomes small, the iteration direction of the clock jump value is positive, and k takes the value of 1; otherwise, the iteration direction of the clock hop value is negative, and k takes the value of-1;
the judgment condition B is that timing processing is carried out after two adjacent iterative clock hop value corrections, and the difference delta of data timing residual errors after two adjacent clock hop value corrections is used as an evaluation standard; delta & lt 0 shows that the pulsar timing residual error becomes smaller after the iteration clock jump value, and delta & gt 0 shows that the pulsar timing residual error becomes larger after the iteration correction clock jump;
(3) if the clock jump value is larger than the period P, continuously iterating to search the real clock jump value, continuously iterating to increase the whole period number by taking the pulsar period P as the step length to change the clock jump value, and iterating the corrected value delta t for the ith clock jumpi＝P·(k·Ni+φ0) I +1 th clock iteration correction value Δ ti+1＝Δti+ P.k; and judging whether the clock is the best clock jump or not by judging the conditions A and B.
The threshold value is set to 0.01 in the determination condition a.
Before the step (1), 1 millisecond pulsar with timing precision higher than the set requirement and in a double-star system is selected, and the integral duration, the observation frequency and the total observation data time span of each observation are determined according to the antenna observation capability and the pulsar radiation intensity.
The invention has the beneficial effects that: and 1 pulsar is observed by taking the time after the interruption and restart as a reference, so that high-precision calculation of any clock jump value can be realized, and support is provided for accurate recovery of the time signal after the interruption.
Drawings
FIG. 1 is a schematic diagram of clock hopping causing pulsar phase hopping;
FIG. 2 is a flow diagram of an embodiment for correcting time jumps using a single pulsar observation;
FIG. 3 is a timing residual diagram of pulsar J0437-4715;
FIG. 4 is a schematic diagram of the change in timing residuals from J0437-4715 caused by reference clock jumps.
Detailed Description
The present invention will be further described with reference to the following drawings and examples, which include, but are not limited to, the following examples.
The rotation of the pulsar is stable, for the same reference clock, the Arrival Time (TOA) of pulses observed by the pulsar at different moments has correlation, namely, the phase of a pulse signal has correlation, and researches show that the phase consistency of the pulses of the pulsar at different moments is better than 0.1% of the phase, namely, the phase stability is high. If a reference clock jumps, the observed pulse phase after the clock jump will also jump. However, the existing pulsar timing technology can only measure the phase jump in less than 1 period, and the phase measurement range is as follows: 0.5-0.5, the integer phase period variation caused by clock jump cannot be judged, i.e. the problem of phase ambiguity of the whole cycle exists, as shown in FIG. 1.
Pulsar timing analysis is to study the correlation of the measured pulse arrival time TOA at different times. The ground pulsar observation station is influenced by the rotation and revolution of the earth, is not an inertial system, and generally selects a solar system centroid reference system as a basic reference system. Therefore, the TOA obtained by the observation station needs to be converted to the TOA at the solar system centroid SSB, so as to eliminate the external influence on the time delay of the pulse signal, and only leave the characteristic capable of reflecting the pulse star intrinsic radiation signal. The TOA conversion process mainly comprises geometric delay, gravitational delay, relativistic time conversion (TT conversion to TCB), dispersion delay and the like, and the pulsar timing TOA conversion model is
TSSB＝Tobs-Δclock-ΔR-ΔS-ΔE-ΔA-ΔD (1)
Wherein, TSSBIs the time, T, at which the pulse arrives at the solar system centroid, SSBobsIs the time of arrival of the pulse at the observation station (with the observation station atomic clock as the reference time), ΔclockIs the time deviation, Δ, of the atomic clock of the observation station relative to the earth's time TTRIs the Roemer delay, i.e. the geometric time delay, Delta, caused by the earth's relative motion with the solar system centroidSIs gravitational delay, an additional time delay, Δ, due to space-time bending caused by massive celestial bodies in the solar systemEIs Einstein delay, i.e. the delay of relativistic time (the delay of TT to TCB), ΔAIs the earth's atmospheric delay, ΔDIs the dispersion delay, i.e. the delay of the observed signal as it propagates in the interplanetary medium relative to propagation in a vacuum. If the pulsar is in a double-star system, the influence of double-star orbit on the pulsar signal needs to be corrected.
According to the formula, the accuracy of the reference clock directly influences the TOA time conversion accuracy, the solar system planet calendar is used in the TOA conversion process, accurate time information required for reading the solar system planet calendar is needed, and if the reference clock has errors, the error in reading the planet calendar is caused. If the pulsar is in a double-star system, the calculation of the double-star orbit also needs reference time, and the reference time error causes errors in the calculation of the double-star orbit delay. Therefore, if the reference time is in clock jump, the TOA conversion error caused by the time error will be reflected in the timing residual, which is mainly represented by 3 types: 1) systematic phase jumps of less than 1 spin cycle; 2) annual trend items caused by reading errors of solar system planet calendar tables; 3) and a double-star orbit error trend term caused by the double-star orbit reference time error. The amplitude of each error trend item is closely related to the size of the clock hop value. Therefore, the clock hop value can be accurately solved by utilizing the rule.
Using a single pulsar to detect clock hops, assuming that the pulsar ephemeris parameters are precisely known, the main ephemeris parameters include: pulsar rotation parameters, position parameters, double-star orbit parameters (if double-star), and the like. The pulse ephemeris parameter values can be obtained by analyzing the timing data before clock jump. The single pulsar timing data is used for resolving clock hopping, and the pulsar timing residual data of the whole time span can be divided into two parts: 1) timing data before clock jump, residual error ResBefore the clock jumps(ii) a 2) Timing data after clock jump, residual error ResAfter the clock jumps。
The basic idea of using single star to solve the clock jump value is to fit the decimal period phase value phi0Then, the whole-cycle phase of the pulsar is taken as a step length (namely 1 is taken as the step length), and the clock jump value Δ t is continuously corrected in an iterative way, wherein the clock jump correction value formula is as follows:
Δt＝P·(Ni+φ0) (2)
wherein P is the rotation period of pulsar, NiIs the full-cycle phase ambiguity value for the ith iteration.
And correcting the reference time by taking the clock jump value delta t as a correction quantity, timing and fitting again, and judging whether the clock jump value fitting value is reasonable or not mainly according to the following two standards in the clock jump value fitting process.
A. The method comprises the following steps of judging whether a fitted clock jump fitting value is reasonable or not by taking a clock jump timing residual value as a standard, wherein for the same pulsar observation system, the timing residual value obtained in different time periods is not changed greatly, namely when timing analysis is carried out after clock jump is accurately corrected, the relative deviation of the timing residual value of timing data before and after clock jump is less than 0.01, and the formula is as follows:
B. timing processing is carried out after two adjacent iterations of clock jump value correction, and data timing residual Res is obtained after two adjacent iterations of clock jump value correctionAfter the clock jumpsThe difference was used as an evaluation criterion
Delta < 0, indicating the pulsar timing residual Res after the iterative clock hopping valueAfter the clock jumpsWhen the clock jump correction value is reduced, namely the clock jump correction value tends to converge to a true value, iteration correction can be continued; if delta is larger than 0, iteratively correcting pulsar timing residual error Res after clock jumpAfter the clock jumpsWhen the value becomes larger, the clock jump correction value begins to diverge and begins to deviate from the true value, and the clock jump iteration direction needs to be reversed.
The specific steps of resolving the reference time jump value based on the single pulsar observation data are as follows:
(1) fitting to obtain decimal phase jump value phi0
Fitting the whole time span data (including all data before and after clock Jump) of the pulsar by using the phase Jump fitting function of pulsar timing software tempo2 to obtain rough decimal phase Jump before and after clock JumpJump value phi0And then P.phi0The value is used as the initial value of the fit-to-clock-hop value for the subsequent iteration.
(2) Judging the direction of the clock jump value correction value
First, an initial clock jump value P.phi is determined0If it is the final clock jump value, if it is the clock jump value P.phi0And after the reference clock is corrected, timing processing (no fitting) is carried out on the whole data, the timing analysis result meets the clock jump fitting judgment condition A, and the initial clock jump value is the final clock jump fitting value.
If the initial value P.phi0If the clock value is not the final clock value, the positive and negative of the clock value need to be judged, and 1 pulse cycle P is added to the initial value, namely: and (1+ phi), and the delta t is used as a clock jump correction value, and the whole timing data (before and after the clock jump) is subjected to timing analysis again after the clock jump is corrected. Analyzing the direction k of clock jump value correction according to the judgment condition B, if the residual error value after clock jump becomes small, the iteration direction of the clock jump value is positive, and k takes the value of 1; otherwise, the iteration direction of the clock hop value is negative, and k takes the value of-1.
(3) Searching for the size of the given clock jump
If the clock hop value is larger than the period P, continuously iterating to search the real clock hop value, taking the pulsar period P as the step length, changing the clock hop value by continuously iterating to increase the whole period number, and judging whether the clock hop is the optimal clock hop or not according to the judgment conditions A and B given above.
According to the single-star clock jump value calculation steps given above, firstly, the clock jump initial value P.phi is given0And then, calculating and judging the direction k of a clock jump correction value according to the initial value, wherein the iteration integer period number of the clock jump is N, the value of the iteration integer period number is 0,1,2,3. Namely, the iteration correction value of the ith clock jump is as follows:
Δti＝P·(k·Ni+φ0) (5)
the iteration correction value of the (i + 1) th clock jump is as follows:
Δti+1＝Δti+P·k (6)
according to the clock-jump value Δ t given aboveiAnd Δ ti+1Respectively counting the remaining timeIn contrast, the above determination condition A, B is used to determine whether the clock is the optimum clock skip value. The final clock hop fit value is given by continuously iterative searching.
The principle of detecting the clock jump by using a single pulsar is based on the trend reflected in the final timing residual error caused by the reference time error of the solar system planet calendar or the double-star orbit parameter, and then the clock jump value is obtained according to the trend fitting in the residual error, so that the pulsar needs to be subjected to timing observation with a certain time span after the clock jump occurs, and the longer the data span is, the better the clock jump detection is.
In candidate pulsar for detecting clock hops, pulsars in a double-star system are preferentially selected, so that the clock hop detection efficiency is improved by the double-star orbit characteristic on the one hand; on the other hand, the two-star orbit represents an orbit period term (day) in the timing residual, and the planet calendar represents a anniversary term (year), so that the two-star system pulsar greatly shortens the observation data span required after clock jump. At present, the shortest orbit period of the two stars is 1.5 hours, namely the star is observed for 1.5 hours after the clock jump occurs, and the clock jump correction value can be calculated by utilizing the timing data.
The time jump correction implementation scheme by utilizing single pulsar observation comprises the following steps:
the clock jump value detection of the time signal can be realized by observing a single pulsar under the assumption that the reference time frequency system for observing the pulsar is interrupted, so that the time signal is discontinuous after the time frequency system is restarted and the time jump phenomenon is generated. The following gives an embodiment of correcting the clock jump value of the reference atomic clock by using observation J0437-4715, and the specific implementation mode is as follows:
(1) pulsar observation scheme making after clock jump
Firstly, 1 millisecond pulsar (such as J0437-4715) with high timing precision in a double-star system is selected from pulsar historical data observed by the antenna. And determining the integral duration, observation frequency, total observation data time span and the like of each observation according to the observation capability of the antenna and the radiation intensity of the pulsar.
(2) Timing observations of candidate pulsar
And (3) carrying out conventional timing observation on the pulsar J0437-4715 according to a formulated scheme by taking the time provided by the atomic clock after restarting as a reference, for example: the integration period for each observation was 20 minutes, 5 observations per day, and at least 6 consecutive days (5.7 days for the source two-star orbital cycle). And acquiring an integral profile and pulse arrival time TOA data information by professional pulsar data processing software PSRCHIVE.
(3) The average deviation of the phase before and after clock jump is obtained by timing analysis
Utilizing pulsar timing data processing software tempo2 to carry out unified timing analysis on historical data before J0437-4715 clock jumps and observed data after clock jumps to obtain a pulse phase jump value decimal part phi before and after time jumps0。
(4) Searching for pulsar whole-cycle ambiguities caused by clock jumps
In the form of P.phi0And (4) taking the pulsar period P as a step length as an initial value, and obtaining a clock jump correction value delta t by iterative search by utilizing a single-star clock jump resolving method.
(5) The calculation gives a time jump value.
And correcting the reference time by using the searched clock jump correction value delta t, and performing timing fitting by using tempo2 again to obtain an updated clock jump correction value delta t'.
(6) Correcting system time
And (4) utilizing the clock jump correction value delta t' obtained by calculation to realize the time calibration of the reference system by controlling the time-frequency system.
Then, single pulsar detection time hopping method simulation verification is carried out by utilizing data observed by 40 m antenna pulsar J0437-4715 of Hao at national time center of China. The observation data span is MJD: 58454.6-58789.7, for a total of 335 days, 152 TOA data points, and if no clock jump occurs, the total data timing residual is 386ns, and the timing residual is shown in FIG. 3.
Assuming that the system reference time of the Haoying 40-meter observation station suddenly slows down by 20s at the MJD58600 moment, namely the time jump value is-20 s, the clock jump affects the timing residual errors of J0437-4715 as shown in FIG. 4, the black point is the pulsar timing residual error when the clock jump does not occur, the pulse phase is stable, the red point is the timing residual error observed after the clock jump occurs, the residual error points are distributed and dispersed, and present a certain regularity, and errors are generated due to the system reference time, so that errors are generated in the reading time of the two-star orbit parameters and the solar system planet ephemeris parameters, and the induced two-star orbit periodic change and the planet ephemeris anniversary change are generated, but the observed data span after the clock jump is 189 days, and the whole anniversary change cannot be reflected.
In the basic function of the timing software tempo2, clock jump correction value fitting software is compiled according to the single-star clock jump calculation algorithm given above, and the high-precision fitting function of the clock jump correction value is realized. When the software is used for fitting the clock jump correction value, the parameters of the pulse ephemeris are assumed to be known, and the parameters of the pulse ephemeris are obtained by fitting the timing data before the clock jump. Then, clock jump correction values are calculated by using clock jump fitting software, and the table below shows the results given by fitting.
Table using parameters associated with J0437-4715 fitting clock hops
| Parameter name | Parameter value | Error of the measurement | Whether to fit or not |
| The Chijing meridian | 04:37:15.9125508 | 5.4E-6 | Whether or not |
| Declination | -47:15:09.20867 | 0.00011 | Whether or not |
| Frequency of | 173.68794573754 | 3.1E-10 | Whether or not |
| Reciprocal of 1 order of frequency | -1.7284E-15 | 1.0E-18 | Whether or not |
| Correction value of clock jump (second) | 19.999999988 | 6.4E-08 | Is that |
The previously simulated observation system time is slowed by 20s (-20s) and thus the actual correction value for the system time is 20 s. In the table, the clock jump correction value calculated by using the single star detection method is 19.999999988s, the error is 64ns, and the deviation from the actual clock jump correction value is 12 ns. At present, the TOA measurement precision of Haohein 40-meter antenna observation J0437-4715 is about 300ns, the fitting precision of the clock jump correction value calculated based on the source is far better than that of the TOA measurement precision, and the clock jump correction value calculation precision is further improved along with the improvement of the measurement precision of the pulsar TOA in the future.
Claims (6)
1. A method for observing and detecting atomic clock jumps by using a single pulsar is characterized by comprising the following steps:
(1) taking the time provided by the atomic clock after restarting as a reference, and carrying out timing observation on the pulsar to obtain a pulsar data integral profile and a pulse arrival time TOA;
(2) the historical data before clock jump and the observed data after clock jump of pulsar are timed and analyzed uniformly to obtain the decimal part phi of the pulse phase jump value before and after time jump0；
(3) In the form of P.phi0Taking the pulsar period P as a step length as an initial value, and iteratively searching to obtain a clock jump correction value delta t;
(4) correcting the reference time by using the clock jump correction value delta t, and repeating the steps (1) to (3) to obtain an updated clock jump correction value delta t';
(5) and controlling the time frequency system by using the clock jump correction value delta t' to realize the time calibration of the reference system.
2. The method for detecting atomic clock hops using single pulsar observations as claimed in claim 1, wherein said pulsar selects a pulsar in a two-star system.
3. The method for detecting atomic clock hops by using single pulsar observation according to claim 1, wherein the step (3) obtains the clock hop correction value Δ t by using a single-star clock hop solution method through iterative search; the single-satellite clock-jump calculation method obtains a final timing residual error of a solar system planet calendar or a double-satellite orbit parameter caused by a reference time error, and then obtains a clock jump value according to trend fitting in the residual error.
4. The method for detecting atomic clock hops by using single pulsar observation according to claim 3, wherein the single pulsar clock hop calculation method comprises the following steps:
(1) fitting the whole time span data of the pulsar to obtain a rough decimal phase jump value phi before and after the clock jump0And then P.phi0The value is used as the initial value of the subsequent iteration fitting clock hop value;
(2) judging the initial clock jump value P phi0If it is the final clock jump value, if it is the clock jump value P.phi0After the reference clock is corrected, timing processing is carried out on the whole data, the timing analysis result meets the judgment condition A, and the initial clock hop value is the final clock hop fitting value;
the judgment condition A is that the relative deviation of timing residual values of the timing data before and after clock jump is smaller than a set threshold value;
if the initial value P.phi0If the clock jump value is not the final clock jump value, judging whether the clock jump value is positive or negative, adding 1 pulse cycle P on the initial value as a clock jump correction value, correcting the clock jump, and then timing and analyzing the whole timing data again; analyzing the direction k of clock jump value correction according to the judgment condition B, if the residual error value after clock jump becomes small, the iteration direction of the clock jump value is positive, and k takes the value of 1; otherwise, the iteration direction of the clock hop value is negative, and k takes the value of-1;
the judgment condition B is that timing processing is carried out after two adjacent iterative clock hop value corrections, and the difference delta of data timing residual errors after two adjacent clock hop value corrections is used as an evaluation standard; delta & lt 0 shows that the pulsar timing residual error becomes smaller after the iteration clock jump value, and delta & gt 0 shows that the pulsar timing residual error becomes larger after the iteration correction clock jump;
(3) if the clock jump value is larger than the period P, continuously iterating to search the real clock jump value, continuously iterating to increase the whole period number by taking the pulsar period P as the step length to change the clock jump value, and iterating the corrected value delta t for the ith clock jumpi＝P·(k·Ni+φ0) I +1 th clock iteration correction value Δ ti+1＝Δti+ P.k; and judging whether the clock is the best clock jump or not by judging the conditions A and B.
5. The method for detecting atomic clock hops using single pulsar observation according to claim 4, wherein a threshold value of 0.01 is set in said determination condition A.
6. The method for detecting atomic clock hops by single pulsar observation according to claim 4, wherein 1 millisecond pulsar with timing precision higher than the set requirement and in a two-star system is selected before the step (1), and the integral duration, observation frequency and total observation data time span of each observation are determined according to the antenna observation capability and the pulsar radiation intensity.
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