CN106289239B - The method for eliminating wideband time domain interference in pulsar arrival time data - Google Patents
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Abstract
The present invention relates to astrophysics technical fields, more particularly to a kind of method of wideband time domain interference in elimination pulsar arrival time data, it include: the pulse signal for observing pulsar, obtain the recurrent pulses profile of pulsar, the recurrent pulses profile of pulsar is carried out to eliminate dispersion delay disposal, the wideband radio interference in pulsar pulse data signal is observed, the wideband time domain interference in pulsar arrival time data is eliminated.The present invention utilizes the correlation of wideband time domain interference, subtract each other the wideband time domain interference in the time domain interference elimination observations of pulsar data for eliminating wideband by channel, obtain true pulsar profile, the precision for improving pulsar arrival time, provides more reliable guarantee for the arrival time observational study of pulsar.
Description
Technical field
The present invention relates to astrophysics technical fields, more specifically to a kind of elimination pulsar arrival time data
The method of middle wideband time domain interference.
Background technique
Pulsar is one of big astronomical discovery the 1960s four, its discovery generates the present age astrophysical development
Tremendous influence, correlative study work once obtain Nobel Prize in physics twice respectively, this shows the observation and theory of pulsar
Research has great scientific meaning, and the observational study of pulsar is always the hot spot of field in astrophysics, it is that research is extreme
" natural laboratory " of physical property and physics law under physical condition.
The most significant feature of pulsar is exactly to have the extremely stable rotation period, long term monitoring the result shows that,
The long-time stability in period can compare favourably with atomic clock, even better than atomic clock.Radio astronomy observation is looked in the distance using radio
Mirror receives the pulse signal of the pulsar from cosmic space, carries out the spoke that period folding obtains pulsar to the data of pulsar
Penetrate the time of the signal arrival earth of profile and pulsar, i.e. pulsar arrival time.The research of pulsar is concentrated mainly on arteries and veins
The radiation profile and arrival time research of star are rushed, the research of pulsar profile can study the radiation characteristic and spoke of pulsar itself
Penetrate process；The research of pulsar arrival time can study the stability of pulsar and the application study of pulsar, such as pulsar meter
When and pulsar navigation research.
Since pulsar signal includes a large amount of system noise and radio interference noise, the research to pulsar is first had to
Interference is eliminated in consideration.
In digital processing field, common interference elimination method mainly has filtering and smooth, and pulsar signal
Inherently a kind of pulse, the acquisition of opposite and data with for data analysis, itself be exactly a kind of noise, common filtering with
It is smooth to cause filtering or smoothing effect to the signal of pulsar simultaneously, and the essence of pulsar research is exactly to pass through research pulse
The profile of star studies every property of pulsar, it is desirable that is eliminating the wheel that pulsar itself cannot be influenced while radio interference
Profile shape and feature.It is required so common filtering is eliminated with the interference for not being able to satisfy observations of pulsar smoothly.
Have in the world in observations of pulsar research time domain wideband radio interference elimination method at present: self-adaptive routing；Zero
Dispersion channel integral eliminates capable and experienced interference method.
Self-adaptive routing is most effective interference elimination method in the observation of current PRF star, but self-adaptive routing needs
Complicated hardware environment, needs two telescopes, receiver and real-time acquisition terminal, two telescopes be respectively primary telescope and
With reference to telescope, this method is effective, but implements extremely difficult, it is necessary first to establish complicated hardware environment, simultaneously
Adaptive filter algorithm needs debugging repeatedly, is only applied at present in Australian Parkes observatory.
Zero dispersion channel integral eliminates capable and experienced interference method as the elimination wideband radio interference of current pulsar Data processing
Main method, this method are integrated using channel zero dispersion amount, and noisy time point is found out, and then utilize surrounding time point
Data carry out interpolation and substitute the data at the time point, still, this method also a degree of shadow while eliminating radio interference
The chamfered shape of pulsar is rung.
Therefore, the technical issues of those skilled in the art's needs urgently solve is exactly: the proposition how to innovate
The radio interference of time domain wideband is eliminated in a kind of measure while not influencing pulsar chamfered shape.
Summary of the invention
To solve the above-mentioned problems, the pulsar of larger dispersion is eliminated in the time domain interference of radio wavelength band observation data, is obtained
Obtain more true pulsar profile and arrival time.The technical solution adopted in the present invention is as follows: a kind of elimination pulsar arrives
The method interfered up to wideband time domain in time data, comprising the following steps:
S1: the pulse signal of pulsar is observed；
It is received using radio telescope from pulsar signal in cosmic space, observes pulsar arrival time, the arteries and veins
Star signal is rushed after radio telescope focuses, after being mixed after being amplified by high sensitive receiver, digitlization is carried out and adopts
Collection, in observations of pulsar, since pulsar is simultaneously emitted by multi-frequency pulse signal, all pulse signals pass through interstellar space
After propagation, the time that the signal of different frequency reaches the earth is different；
S2: the recurrent pulses profile of pulsar is obtained；
Under the conditions of wideband, while the high frequency resolution of acquisition pulse star signal, high time resolution data, by right
The progress period is superimposed to obtain periodically pulsing profile after channel carries out dispersion delay correction；
S3: the recurrent pulses profile of pulsar is carried out to eliminate dispersion delay disposal；
Due to the effect of dispersion, different frequency dispersion delay is not eliminated, will lead to the profile deformation of pulsar, or can't see
The broadband signal received is divided into multiple channels by pulsar signal, observations of pulsar system, and the dispersion for calculating each channel is prolonged
Late, after the dispersion delay for deducting each channel, then channel superposition is carried out, that is, realizes and the recurrent pulses profile of pulsar is carried out
Eliminate dispersion delay disposal；
S4: the wideband radio interference in observation pulsar pulse data signal；
The recurrent pulses profile of pulsar is carried out after eliminating dispersion delay disposal, is had very in the place for having pulse signal
More radio interference, radio interference are superimposed upon on pulse signal, cause serious influence to the profile of pulsar and arrival time；
S5: the wideband time domain interference in pulsar arrival time data is eliminated；
The characteristic postponed using the dispersion of pulsar is eliminated in pulsar arrival time data by interference cancellation algorithm
Wideband time domain interference.
Further, the step S2 includes:
S21: astronomical receiver receives the pulsar signal of the interstellar matter by cosmic space, by the frequency of pulsar signal
Signal in rate bandwidth deltaf f amplifies, mixes down to intermediate frequency；
S22: intermediate-freuqncy signal is injected into terminal system, the letter that terminal system is Δ f frequency bandwidth using immediate frequency cable
Number it is divided into v1、v2、v3…..vnN subchannel, each subchannel bandwidth are Δ f/n；
S23: with subchannel vn/2On the basis of, calculate subchannel v1、v2、v3…..vnTo subchannel vn/2Time delay Δ
t1、Δt2、Δt3……Δtn；
S24: correcting the time delay of each subchannel, is overlapped to the data of each subchannel, obtains pulsar
Profile.
Further, the effect of the interstellar matter in the cosmic space is to cause to postpone to the pulse signal of pulsar.
Further, interference cancellation algorithm described in step S5 includes:
In actual observation, the numerical value of each sample record is denoted as pij, wherein i is channel position, and range is 0~n, and j is
Sampling sequence number, the period of pulsar are T, and sample rate is Δ τ, and the sampling number of a cycle is T/ Δ τ.
S51: channel correction
The data of T/ Δ τ times sampling of n subchannel are normalized, the high frequency attenuation of n sub- channel datas of correction,
The power response for calculating each channel carries out arithmetic mean to the period points in channel, with the mean power in any one channel
Channel correction is carried out on the basis of response, recalculates the numerical value p ' sampled every time in each channelij；
S52: dispersion delay and pulsar profile width are calculated
The dispersion delay time in whole bandwidth is calculated by dispersion delay time formula, arteries and veins is obtained by pulsar star catalogue
The nominal contour of star is rushed, or calculates the profile width W of pulsar using the nominal contour of historical datapsr；
S53: interference is eliminated
Calculate the value of the channel data sampled point of pulsar, the value of the sampled point includes: that pulsar signal value, radio are dry
Value, system noise value are disturbed, the pulsar signal value is only in the place with the presence of pulsar impulse radiation, the radio interference value
For random disturbances noise figure, the system noise all exists in whole cycle；
If dispersion delay time Δ t > 2Wpsr, in the cycle T of pulsar, there are pulsar signal, i.e., i-th in the i-th channel
The value of the channel data sampled point in channel includes: pulsar signal value, radio interference value, system noise value, then the i-th channel+n/2
The value for not having the channel data sampled point in pulsar signal and the i-th channel+n/2 includes: radio interference value, system noise value；
The value of the channel data sampled point in the i-th channel is subtracted into the value of the channel data sampled point in the i-th channel+n/2 to obtain the final product
To pulsar signal value.
Further, the profile width WpsrFor the phase width at signal both sides edge.
Further, the dispersion delay time formula are as follows: Vt=4.148808DM [(v0)-2-(vn)-2], DM in formula
For pulsar dispersion measure, unit is that parsec is per cubic centimeter, and the parsec is a kind of length unit astronomically, 1 second
Gap is equal to 3.2615637769744079138 light-years, v0、vnFor frequency, unit GHz.
Compared with the prior art, the invention has the benefit that
The present invention utilizes the correlation of wideband time domain interference, subtracts each other the time domain interference elimination pulse for eliminating wideband by channel
Star observes the wideband time domain interference in data, obtains true pulsar profile, improves the precision of pulsar arrival time, is arteries and veins
The arrival time observational study for rushing star provides more reliable guarantee.
Detailed description of the invention
Fig. 1 is the method flow diagram for eliminating wideband time domain interference in pulsar arrival time data of the invention；
Fig. 2 is the pulse signal schematic diagram of observation pulsar of the invention；
Fig. 3 is pulsar pulse arrival time of the invention with frequency variation diagram；
Fig. 4 is the recurrent pulses profile schematic diagram for obtaining pulsar of the invention；
Fig. 5 is the pulsar profile and time domain interference figure of the invention without eliminating when dispersion delay；
Fig. 6 is the pulsar profile and time domain interference figure eliminated after dispersion of the invention；
Fig. 7 is calculating pulse profile width diagram of the invention；
There is no the pulsar profile and time domain interference figure when eliminating dispersion delay in Fig. 8 the embodiment of the present invention；
Fig. 9 is De-dispersion but the profile diagram without eliminating the pulsar after interfering in the embodiment of the present invention；
Figure 10 is true pulsar profile diagram after eliminating time domain interference in the embodiment of the present invention；
Figure 11 is after eliminating time domain interference in the embodiment of the present invention with true after system white noise substitution negative value pulse profile
Real pulsar profile diagram.
Specific embodiment
The present invention is further described below combined with specific embodiments below.
As shown in Figure 1, the present invention provides a kind of method of wideband time domain interference in elimination pulsar arrival time data,
The following steps are included:
S1: the pulse signal of pulsar is observed；
As shown in Fig. 2, being received from pulsar signal in cosmic space, when observation pulsar reaches using radio telescope
Between, the pulsar signal is after radio telescope focuses, and after being mixed after being amplified by high sensitive receiver, carries out
Digital collection.
As shown in figure 3, in observations of pulsar, since pulsar is simultaneously emitted by multi-frequency pulse signal, all pulses
For signal after interstellar space propagation, the time that the signal of different frequency reaches the earth is different, and ordinate is channel in Fig. 3,
Different channels is different frequency, and the signal in the signal rather low-frequency channel of hf channel, which arrives first, takes things philosophically survey station.
S2: the recurrent pulses profile of pulsar is obtained；
As shown in figure 4, under the conditions of wideband, while the high frequency resolution of acquisition pulse star signal, high time resolution
Data are superimposed to obtain periodically pulsing profile by the progress period after carrying out dispersion delay correction to channel；It can be with from Fig. 4
It was found that pulse signal is very strong, while having many radio to interfere in the place for having pulse signal, these interference are superimposed upon pulse letter
On number, by pulsar profile and arrival time cause serious influence, especially high-precision pulsar arrival time is seen
Survey research and the research of pulsar radiation mechanism.
Observations of pulsar system principle is as shown in figure 4, the interstellar matter (ISM) that the signal of pulsar passes through cosmic space
Afterwards, the effect of ISM causes to postpone to the pulsar signal of pulsar, will believe frequency bandwidth for Δ f after astronomical receiver
Number amplification mixes down to intermediate frequency, is injected into terminal system by immediate frequency cable, terminal system is the signal point that frequency bandwidth is Δ f
At v1、v2、v3…..vnN subchannel, each subchannel bandwidth are Δ f/n.With vn/2On the basis of subchannel, v is calculated1、v2、
v3…..vnEach subchannel is to vn/2The time delay Δ t in channel1、Δt2、Δt3……Δtn, correct the time in each channel
The data in each channel are overlapped after delay, to obtain the profile of pulsar.
S3: the recurrent pulses profile of pulsar is carried out to eliminate dispersion delay disposal；
Due to the effect of dispersion, different frequency dispersion delay is not eliminated, will lead to the profile deformation of pulsar, or can't see
The broadband signal received is divided into multiple channels by pulsar signal, observations of pulsar system, and the dispersion for calculating each channel is prolonged
Late, after the dispersion delay for deducting each channel, then channel superposition is carried out, that is, realizes and the recurrent pulses profile of pulsar is carried out
Eliminate dispersion delay disposal.As shown in figure 5, obtaining very strong pulsar pulse signal after eliminating dispersion delay.
S4: the wideband radio interference in observation pulsar pulse data signal；
The recurrent pulses profile of pulsar is carried out after eliminating dispersion delay disposal, is had very in the place for having pulse signal
More radio interference, radio interference are superimposed upon on pulse signal, cause serious influence to the profile of pulsar and arrival time；
S5: the wideband time domain interference in pulsar arrival time data is eliminated；
The characteristic postponed using the dispersion of pulsar is eliminated in pulsar arrival time data by interference cancellation algorithm
Wideband time domain interference.
The size of pulsar dispersion is related at a distance from pulsar, its remoter dispersion values of distance are bigger, and the expression of dispersion is public
Formula is as follows:
Wherein DM is pulsar dispersion, l is the distance of pulse, neFor milky way galaxy average electron density.
Different frequency electromagnetic wave can be expressed as by time delay after interstellar space:
Vt=4.148808DM [(v0)-2-(v1)-2] (2)
Wherein Vt is the arrival earth receiver time delay of different frequency signals, and unit is millisecond, and DM is pulse star color
Amount is dissipated, unit is that parsec is per cubic centimeter, and parsec is a kind of length unit astronomically, and 1 parsec is equal to
3.2615637769744079138 light-year, v0、v1For frequency, unit GHz.
Observations of pulsar data disappear, and to interfere purpose be to eliminate narrowband interference in observations of pulsar band limits and when wideband
Domain interference.The method for usually eliminating pulsar interference is to find to interfere on the channel or time domain of interference by certain algorithm
The data in channel are eliminated in point, the interference on frequency domain, are using local value in time domain plus in the random noise substitution time domain of rms
Noise spot, this method can eliminate the channel of interference and the data of interference, obtain preferable profile, still, if interference
It is superimposed upon on the profile of pulsar, the value at the moment should be at this time:
Tsig=Tsys+Tpsr+Trfi (3)
In formula: TsigTotal signal strength, TpsrThe signal of pulsar, TsysFor system noise, TrfiFor radio interference.
In order to eliminate the influence of interference, and the sampled value at this moment is substituted using the value of system noise, this moment
Value is set as system noise, that is, Tsig~=Tsys, the radiant power of pulsar is had lost, this will improve the arrival of pulsar
Temporal noise, while the radiation profile of pulsar can be changed, so that the precision of the arrival time of pulsar is influenced, to pulsar
Radiation mechanism research impacts.
In the present invention, the numerical value for recording each observed samples is pij, i is channel position, and range is 0~n, and j is sampling
Serial number.The period of pulsar is T, and sample rate is Δ τ, and a cycle uses points for T/ Δ τ.
The step S5 includes:
S51: channel correction
The data of T/ Δ τ times sampling of n subchannel are normalized, the system of n sub- channel datas of correction is corresponding
And high frequency attenuation, the power response in each channel is calculated, arithmetic mean, calculation formula are carried out to the period points in channel are as follows:
Channel correction is carried out on the basis of the response of the mean power in any one channel, recalculates each of each channel
The numerical value p ' of samplingij；Such as on the basis of kth channel, then:
S52: dispersion delay and pulsar profile width are calculated
The dispersion delay time in whole bandwidth is calculated by dispersion delay time formula, can be obtained by formula (2):
Vt=4.148808DM [(v0)-2-(vn)-2] (6)
The nominal contour of pulsar is obtained by pulsar star catalogue, or calculates pulse using the nominal contour of historical data
The profile width W of starpsr；Pulse profile width is the phase width at signal both sides edge.
As shown in fig. 7, profile starts from 0.485, end at 0.519, relative width are as follows: (0.519-0.485) × T=
0.034T, T are the period of pulsar.
S53: interference is eliminated
In the present invention, the characteristic postponed using the dispersion of pulsar, the time of arrival (toa) of the pulsar of different frequency
Different, the signal of high frequency first reaches, the rear arrival of low frequency, remembers that the arrival time of high-frequency signal is tpsr-h, low frequency signal arrives
It is t up to the momentpsr-l, then tpsr-h< tpsr-l, and the interference signal same time reaches, trfi-h=trfi-l, by calculating pulsar
Radiation profile and pulsar observation bandwidth delay, if pulsar dispersion delay in observation bandwidth is greater than twice of arteries and veins
Rush star bandwidth deltaf t=tpsr-l-tpsr-h> 2Wpsr, after being calibrated by channel, channel, which reports to the leadship after accomplishing a task to subtract each other, can effectively eliminate penetrating for wideband
Electrical interference, the signal without influencing pulsar.
The value of the channel data sampled point of pulsar can be calculated by formula (3):
WhereinFor system noise, whole cycle all exists；Pulsar signal only has in the place for having impulse radiation
Signal,It is random disturbances noise for radio interference.
The value of the channel data sampled point of pulsar includes following several situations:
(1) there is no pulse signal and interference sample:
(2) there is no pulse signal, noisy sampling:
(3) sampling for having pulsar signal, not interfering with:
(4) there are pulsar signal, noisy sampling:
Since the signal of pulsar postpones with different frequency having time, as Δ t > 2WpsrWhen, there is pulsar letter in the i-th channel
Number when its sampled data are as follows:
Or
And i-th+The channel n/2 does not have pulse signal, sampled data are as follows:
Or
Between different channels, by having after the correction of channel:
The white noise for only remaining pulsar signal and system afterwards is subtracted each other in so channel i and the channel i+n/2
Finally to the profile for obtaining pulsar negative value after subtracting each other, substituted with the random number of the white noise range of system.
So available following conclusions: if dispersion delay time Δ t > 2Wpsr, pulsar period be T in,
There is pulsar signal in i-th channel, i.e. the value of the channel data sampled point in the i-th channel includes: pulsar signal value, radio interference
Value, system noise value, then the i-th channel+n/2 does not have the value packet of the channel data sampled point in pulsar signal and the i-th channel+n/2
Include: the value of the channel data sampled point in the i-th channel is subtracted the port number in the i-th channel+n/2 by radio interference value, system noise value
Pulsar signal value is obtained according to the value of sampled point.
So to dispersion deferred gratification Δ t > 2WpsrPulsar the channel data after correction can be subtracted each other, it is non-
Often effectively eliminate the signal for retaining pulsar while radio interference.
The present invention in practical applications, is handled the measured data of pulsar PSR J1645-0317.Fig. 8 shows
Since dispersion postpones, the pulse profile of dispersion delay and time domain interference is not eliminated；Fig. 9 indicates De-dispersion but without eliminating interference
Afterpulse profile；Figure 10 indicates that eliminating time domain interferes afterpulse profile, and Figure 11 is indicated after eliminating time domain interference, with system white noise
True pulsar profile after substitution negative value pulse profile.As can be seen from Figure 8, the signal of pulsar by dispersion postpone and when
The influence of domain interference, causes pulse profile to deform, or can't see pulsar signal；From fig. 9, it can be seen that eliminating dispersion delay
Very strong pulse signal is obtained afterwards, but there are many interference on pulse profile and background；From Figure 11, Figure 10 and Fig. 8, Fig. 9
Comparison is it can be seen that the interference in elimination time domain that can be extraordinary of the invention obtains true pulse profile.
Above to it is provided by the present invention it is a kind of eliminate pulsar arrival time data in wideband time domain interference method into
It has gone and has been discussed in detail, used herein a specific example illustrates the principle and implementation of the invention, the above implementation
The explanation of example is merely used to help understand method and its core concept of the invention；Meanwhile for the general technology people of this field
Member, according to the thought of the present invention, there will be changes in the specific implementation manner and application range, in conclusion this explanation
Book content should not be construed as limiting the invention.
Finally, it should be noted that the foregoing is only a preferred embodiment of the present invention, it is not intended to restrict the invention,
Although the present invention is described in detail referring to the foregoing embodiments, for those skilled in the art, still may be used
To modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features,
All within the spirits and principles of the present invention, any modification, equivalent replacement, improvement and so on should be included in of the invention
Within protection scope.
Claims (4)
1. a kind of method for eliminating wideband time domain interference in pulsar arrival time data, which comprises the following steps:
S1: the pulse signal of pulsar is observed；
It is received using radio telescope from pulsar signal in cosmic space, observes pulsar arrival time, the pulsar
Signal is after radio telescope focuses, and after amplifying, being mixed by high sensitive receiver, carries out digital collection,
In observations of pulsar, since pulsar is simultaneously emitted by multi-frequency pulse signal, all pulse signals are propagated by interstellar space
After, the time that the signal of different frequency reaches the earth is different；
S2: the recurrent pulses profile of pulsar is obtained；
Under the conditions of wideband, while the high frequency resolution of acquisition pulse star signal, high time resolution data, by channel
The progress period is superimposed to obtain periodically pulsing profile after carrying out dispersion delay correction；
S3: the recurrent pulses profile of pulsar is carried out to eliminate dispersion delay disposal；
Due to the effect of dispersion, different frequency dispersion delay is not eliminated, will lead to the profile deformation of pulsar, or can't see pulse
The broadband signal received is divided into multiple channels by star signal, observations of pulsar system, calculates the dispersion delay in each channel, button
Unless each after the dispersion delay in channel, then channel superposition is carried out, that is, realizes and the recurrent pulses profile of pulsar is eliminated
Dispersion delay disposal；
S4: the wideband radio interference in observation pulsar pulse data signal；
The recurrent pulses profile of pulsar is carried out after eliminating dispersion delay disposal, has in the place for having pulse signal and much penetrates
Electrical interference, radio interference are superimposed upon on pulse signal, cause serious influence to the profile of pulsar and arrival time；
S5: the wideband time domain interference in pulsar arrival time data is eliminated；
The characteristic postponed using the dispersion of pulsar eliminates the width in pulsar arrival time data by interference cancellation algorithm
The interference of frequency time domain；
Interference cancellation algorithm described in step S5 includes:
In actual observation, the numerical value of each sample record is denoted as pij, wherein i is channel position, and range is 0~n, and j is sampling
Serial number, the period of pulsar are T, and sample rate is Δ τ, and a cycle uses points for T/ Δ τ,
S51: channel correction
The data of T/ Δ τ times sampling of n subchannel are normalized, the high frequency attenuation of n sub- channel datas of correction calculates
The power response in each channel is carried out arithmetic mean to the period points in channel, is responded with the mean power in any one channel
On the basis of carry out channel correction, recalculate the numerical value p' sampled every time in each channelij；
S52: dispersion delay and pulsar profile width are calculated
The dispersion delay time in whole bandwidth is calculated by dispersion delay time formula, pulsar is obtained by pulsar star catalogue
Nominal contour, or calculate using the nominal contour of historical data the profile width W of pulsarpsr；
S53: interference is eliminated
The value of the channel data sampled point of pulsar is calculated, the value of the sampled point includes: pulsar signal value, radio interference
Value, system noise value, only in the place with the presence of pulsar impulse radiation, the radio interference value is the pulsar signal value
Random disturbances noise figure, the system noise all exist in whole cycle；
If dispersion delay time Δ t > 2Wpsr, it is in T in the period of pulsar, there is pulsar signal in the i-th channel, i.e., i-th is logical
The value of the channel data sampled point in road includes: pulsar signal value, radio interference value, system noise value, then the i-th channel+n/2 does not have
The value for having the channel data sampled point in pulsar signal and the i-th channel+n/2 includes: radio interference value, system noise value；
The value that the value of the channel data sampled point in the i-th channel subtracts the channel data sampled point in the i-th channel+n/2 is obtained into arteries and veins
Rush star signal value.
2. eliminating the method for wideband time domain interference in pulsar arrival time data as described in claim 1, which is characterized in that
The step S2 includes:
S21: astronomical receiver receives the pulsar signal of the interstellar matter by cosmic space, by the frequency band of pulsar signal
Signal in wide Δ f amplifies, mixes down to intermediate frequency；
S22: intermediate-freuqncy signal is injected into terminal system using immediate frequency cable, terminal system is the signal point that frequency bandwidth is Δ f
At v1、v2、v3…..vnN subchannel, each subchannel bandwidth are Δ f/n；
S23: with subchannel vn/2On the basis of, calculate subchannel v1、v2、v3…..vnTo subchannel vn/2Time delay Δ t1、Δ
t2、Δt3……Δtn；
S24: correcting the time delay of each subchannel, is overlapped to the data of each subchannel, obtains the period of pulsar
Property pulse profile.
3. eliminating the method for wideband time domain interference in pulsar arrival time data as described in claim 1, which is characterized in that
The profile width WpsrFor the phase width at signal both sides edge.
4. eliminating the method for wideband time domain interference in pulsar arrival time data as described in claim 1, which is characterized in that
The dispersion delay time formula are as follows: Vt=4.148808DM [(v0)-2-(vn)-2], DM is pulsar dispersion measure, unit in formula
Per cubic centimeter for parsec, the parsec is a kind of length unit astronomically, and 1 parsec is equal to
3.2615637769744079138 light-year, v0、vnFor frequency, unit GHz.
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