CN106940399A - Temporal frequency apparatus for evaluating based on atomic clock - Google Patents
Temporal frequency apparatus for evaluating based on atomic clock Download PDFInfo
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- CN106940399A CN106940399A CN201710093646.2A CN201710093646A CN106940399A CN 106940399 A CN106940399 A CN 106940399A CN 201710093646 A CN201710093646 A CN 201710093646A CN 106940399 A CN106940399 A CN 106940399A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R23/00—Arrangements for measuring frequencies; Arrangements for analysing frequency spectra
- G01R23/02—Arrangements for measuring frequency, e.g. pulse repetition rate; Arrangements for measuring period of current or voltage
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
- G01K1/20—Compensating for effects of temperature changes other than those to be measured, e.g. changes in ambient temperature
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- General Physics & Mathematics (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
Abstract
The invention discloses a kind of temporal frequency apparatus for evaluating based on atomic clock, the temporal frequency apparatus for evaluating includes base detection module, microprocessor when atomic frequency standard, temperature measurement module, tc compensation, multichannel；The atomic frequency standard is compensated with the temperature system successively, the frequency signal of atomic frequency standard output is received for the tc compensation, base detection module when the temperature system compensation is with the multichannel, for being exported after the temperature system is compensated into the frequency signal received compensation to base detection module during the multichannel；The temperature measurement module is connected with the atomic frequency standard, the temperature information for measuring the atomic clock external working environment；The temperature measurement module is connected with microprocessor, for the temperature information to be sent to the microprocessor；The microprocessor is connected with the tc compensation.
Description
Technical field
The present invention relates to field of circuit technology, more particularly to a kind of temporal frequency apparatus for evaluating based on atomic clock.
Background technology
Atomic clock with the Stability index of its superelevation, have been applied in such as satellite navigation, when base time service, time synchronized,
Many Field of Time and Frequency such as national defense and military.In view of the specific requirement of above-mentioned application field, especially field work is to the severe of environment
Carve and require, the changeable external environment of atomic clock, especially working temperature environment, and the presence of atomic clock system temperature coefficient is always
All it is the problem of the field researcher research, the change of ambient temperature will cause internal system lamp temperature, chamber temperature etc.
The change of core component operating temperature, further results in the unstable of atomic hyperfine 0-0 jump frequencies, final influence system
The stability of system rate-adaptive pacemaker.
The content of the invention
The present invention provides a kind of temporal frequency apparatus for evaluating based on atomic clock, solves above-mentioned technical problem, reaches
It can reduce or offset the shadow of whole machine output signal frequency stability caused by the change of atomic clock external working environment temperature
Loud technique effect.
The present invention provides a kind of temporal frequency apparatus for evaluating based on atomic clock, and the temporal frequency apparatus for evaluating includes original
Base detection module, microprocessor when sub- frequency marking, temperature measurement module, tc compensation, multichannel；The atomic frequency standard successively with it is described
Temperature system is compensated, and the frequency signal of atomic frequency standard output, the temperature system compensation are received for the tc compensation
Base detection module during with the multichannel, for being exported after the temperature system is compensated into the frequency signal received compensation to described
Base detection module during multichannel；The temperature measurement module is connected with the atomic frequency standard, for measuring the extraneous building ring of the atomic clock
The temperature information in border；The temperature measurement module is connected with microprocessor, for the temperature information to be sent to the microprocessor；
The microprocessor is connected with the tc compensation.
It is preferred that, the tc compensation includes DDS external reference clocks end, and base is referred to during for being provided for DDS.
It is preferred that, the tc compensation also includes C field current compensating modules, and the C field currents compensating module includes
VCSS constant current units, C an enamel-covered wire and D/A modules；The output end of the VCSS constant flow modules is connected with the C enamel-covered wire,
The D/A modules of stating are connected with the VCSS constant flow modules；Control voltage after for being changed according to the D/A modules adjusts institute
State the electric current that C enamel-covered wires pass through.
It is preferred that, base detection module is made up of multiple unification circuits during the multichannel.
It is preferred that, counting, latch, microprocessor, high accuracy meter when the unification circuit includes isolated amplifier, walked
Number device, DDS module, filter shape module；The isolated amplifier respectively with it is described walk when count, DDS module be connected, for connecing
Receive the measured clock source simultaneously point two paths of signals after the isolated amplifier, be respectively fed to it is described walk when count, DDS module；Institute
Count and be connected in series successively with the latch, microprocessor, high-resolution counter when stating away；The DDS module, filter shape
Module and high-resolution counter are sequentially connected in series；The microprocessor is connected with DDS module, and the measured clock source is compensation
The frequency signal exported afterwards.
It is preferred that, microprocessor converted by the access to latch after measured clock source frequency values, and lead to
The frequency division value that command word rewrites the measured clock source frequency signal of another road isolated amplifier feeding in DDS is crossed, makes DDS output letters
Number it is 1Hz, ' 0 ' or ' 1 ' signal all the way that filtered shaping is controlled with microprocessor delivers to, obtained through ' with ' computing by microprocessor
The calibrating that device ' 0 ', ' 1 ' is controlled 1PPS signal output.
At least there is following beneficial effect in the application
The application has increased temperature measurement module and tc compensation module newly on conventional atom clock technology.Newly-increased module
It can reduce or offset the shadow of whole machine output signal frequency stability caused by the change of atomic clock external working environment temperature
Ring.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, embodiment will be described below
Needed for the accompanying drawing to be used be briefly described, it should be apparent that, drawings in the following description be only the present invention some
Embodiment.
Fig. 1 is a kind of schematic diagram of time-domain signal optimization Simulation system of the application better embodiment；
Fig. 2 is C field current compensation principle figures；
The schematic diagram of base detection module when Fig. 3 is multichannel；
Fig. 4 is the circuit diagram that frequency source signal sample examines and determine principle；
Fig. 5 is signal source sampling time sequence figure；
Fig. 6 is program execution flow figure.
Embodiment
In order to be better understood from above-mentioned technical proposal, below in conjunction with Figure of description and specific embodiment to upper
Technical scheme is stated to be described in detail.
The application provides a kind of temporal frequency apparatus for evaluating based on atomic clock, and the temporal frequency apparatus for evaluating includes original
Base detection module, microprocessor when sub- frequency marking, temperature measurement module, tc compensation, multichannel；
The atomic frequency standard is compensated with the temperature system successively, and it is defeated to receive atomic frequency standard for the tc compensation
The frequency signal gone out, base detection module when the temperature system compensation is with the multichannel, for temperature system compensation to be connect
Exported after the frequency signal compensation received to base detection module during the multichannel；
The temperature measurement module is connected with the atomic frequency standard, and the temperature for measuring the atomic clock external working environment is believed
Breath；The temperature measurement module is connected with microprocessor, for the temperature information to be sent to the microprocessor；The microprocessor
Device is connected with the tc compensation.
The tc compensation includes DDS external reference clocks end, and base is referred to during for being provided for DDS.The temperature
Compensating coefficient also include C field current compensating modules, the C field currents compensating module include VCSS constant current units, C enamel-covered wires and
D/A modules；The output end of the VCSS constant flow modules is connected with the C enamel-covered wire, described to state D/A modules and VCSS perseverances
Flow module is connected；Control voltage after for being changed according to the D/A modules adjusts the electric current that the C enamel-covered wire passes through.
A) outside DDS FREQUENCY CONTROLs
Come from the DDS external reference clocks end that the frequency output signal fo of atomic frequency standard is delivered in temperature compensation module,
Base is referred to during for being provided for DDS；
The ambient temperature information T for coming from temperature measurement module delivers to microprocessor, for microprocessor to environment temperature T
Change is judged that once T changes, microprocessor will enter line frequency amendment to DDS, and the method that it is specifically corrected is as follows：
If the temperature coefficient of atomic frequency standard system is+1E-12, i.e., ambient temperature T, which often raises 10C, will cause atomic frequency standard system
The change of output signal fo frequency stability generation+1E-12 magnitudes.By taking fo=10MHz as an example, T changes 10C, then f/fo=+
1E-12, i.e. f=(+1E-5) Hz=10Hz, microprocessor need to carry out DDS negative-feedback (- 1E-5) Hz=-10Hz amendment.
The DDS chips used in embodiment is AD9854, when 10MHz is referred to exemplified by base, when without internal PLL lock phases
During ring, its minimum frequency resolution ratio is 10MHz/248(4E-8)Hz.Microprocessor is according to DDS control sequential, and output is accordingly
Level signal act on DDS and its output frequency is changed, while temperature measurement module measurement is obtained into the conversion of temperature T parameter values
For corresponding frequencies correction value, carry out ' 0 ', ' 1 ' to 48 bit frequency registers inside DDS and fill, such as a certain moment atom is frequently
The frequency values of mark output are 10MHz, and the temperature coefficient of the system is+1E-12, and temperature detecting module is sent to the ring of microprocessor
Border temperature information is 10 DEG C of rise, then now microprocessor needs to carry out negative-feedback process to DDS, i.e., DDS is carried out
10MHz-10Hz FREQUENCY CONTROLs are exported, and concrete operating principle is：The f0=10MHz of atomic frequency standard output is delivered to DDS when base
2 process of frequency multiplication, the i.e. frequency of DDS real works are carried out inside reference edge, DDS to it for 20MHz, in above-mentioned 48 frequencies referred to
In rate register, if microprocessor puts ' 1 ' to its 48 wholes, then under the timing control signal of DDS microprocessors, it will export
20MHz frequency, same reason, if microprocessor puts ' 0 ' to its 48 wholes, then the SECO of DDS microprocessors
Under signal, 0MHz frequency will be exported.Now want to export 10MHz-10Hz frequency signals, then corresponding 48 bit frequency register
Value should be：
(10MHz-10Hz) * 248/20MHz=140737488355187 (d)=7FFFFFFFFF73 (h)=
11111111111111111111111111111111111111101110011 (b), microprocessor is in DDS timing control signals
Under, 48 bit frequency control words are write in DDS, DDS then accordingly exports revised frequency signal, i.e. compensation output f1 to user
End.
B) internal C field currents compensation
Referring to Fig. 2, atomic clock output frequency f0 has following relation with magnetic field (C)：
Δ f/f=1.68 × 10-7HΔH (1)
In formula, f is atomic ground state hyperfine structure 0-0 jump frequencies, in actual atomic clock system, above-mentioned atomic clock
Output signal frequency f0 indirect reactions f value；Δ f is the sizes values that actual frequency changes；H is C sizes values of internal system,
As a result of C enamel-covered wire winding methods of helix tube in actual atomic clock system, therefore the electric current I values in upper figure are reacted
H value；Δ H is the sizes values of actual C change.
Thus atomic clock output signal frequency count value and C field currents I transformational relation, its sizes values is with specific one
Atomic clock cavity bubble system and C enamel-covered wire coiling numbers of plies etc. have compared with Important Relations.And we concern C field currents I change
The magnitude that atomic clock output signal frequency can be caused to change, this is the core place of this patent, and this magnitude is with different originals
Secondary clock and difference, approximate range is 10-12—10-11.So when the whole machine output signal frequency reproduction of the preset atomic clock of user
Be worth for f0=10, when 000,000.000,00 (Hz), processor using f0 as reproduction reference frequency value, once in sampling time t
Changes in (such as 10S), i.e. f0=10,000,000.000,0 × (Hz) ' × ' position and anteposition change when,
Processor can change D/A outputs, D/A is through voltage according to transformational relation between actual atomic clock C field currents I and output frequency f0
After the VCCS modules of control electric current source, the electric current I in the C field coils being wound on atomic clock resonant cavity body wall is set to change, from
And C sizes values H is changed, further correct the output signal frequency f0 of atomic clock.
Base detection module during on multichannel
Fig. 3 and Fig. 4 are referred to, base detection module is made up of multiple unification circuits during the multichannel.The unification electricity
Counting, latch, microprocessor, high-resolution counter, DDS module, filter shape module when road includes isolated amplifier, walked；
The isolated amplifier respectively with it is described walk when count, DDS module be connected, for receive measured clock source and process the isolation
Point two paths of signals after amplifier, be respectively fed to it is described walk when count, DDS module；It is described walk when count successively with the latch,
Microprocessor, high-resolution counter are connected in series；The DDS module, filter shape module and high-resolution counter are sequentially connected in series
Connection；The microprocessor is connected with DDS module, and the measured clock source is the frequency signal exported after compensating.
By taking the unification circuit of measured clock source 1 as an example：Measured clock source 1 is loaded into the frequency source signal end in upper figure, warp
Cross after isolated amplifier, counted in being counted when signal enters to walk all the way, when walking and measured clock source 1 is handled, obtain corresponding
Frequency values and deliver to latch 1.Microprocessor converted by the access to latch 1 after measured clock source 1 frequency
Rate value, and the frequency dividing for the frequency signal of measured clock source 1 sent into by another road self-isolation amplifier in command word rewriting DDS
Value, it is 1Hz to make DDS output signals, and ' 0 ' or ' 1 ' signal all the way that filtered shaping is controlled with microprocessor is delivered to, and is transported through ' with '
Calculation obtains being examined and determine the signal output with 1PPS by the control of microprocessor ' 0 ', ' 1 '.
Enabling signal, signal of closing the door when high-resolution counter works in Fig. 4 is referring to Fig. 5, assume that A is reference clock source
Atomic clock output signal after compensating, B is measured clock source N, and simultaneously accredited clock source N=10 platforms, the time T of sampling
For " my god ", then there is a kind of following scheme：To N=1 measured clock source 1, in a certain morning 6：01, microprocessor is according in Fig. 3
The rising edge signal of reference clock source signal is designated as the rising edge of a-signal in Fig. 4, and now processor is to ' with ' door one in Fig. 3
Individual ' 1 signal, is ' 0 ' because now another road of ' with ' door derives from measured clock source signal 1, so whole ' with ' door output
For ' 0 '.We are designated as this moment to enable high-resolution counter " starting counting up " operation；When measured clock source n-signal is passed through in Fig. 4
When the rising edge crossed after isolated amplifier, DDS, filter shape processing arrives, ' 1 ' is obtained with door computing in Fig. 4, is now closed high
Precision Time interval counter counts are operated, as shown in Figure 6, i.e., " terminate to count ".So as to obtain a measured clock source 1 with
Reference clock source time difference data t1 (being x (t) in figure).Morning 6 next day：01, repeat process above so that obtain one it is tested when
Clock source 1 and reference clock source time difference data t2 (is x (t+ Δs t)) in figure, Wo Menyou, Δ t1=t2-t1 repeat Δ t1 above
Process, have formula：
Δ ti=ti+1-ti (2)
Other N=2,3 ... 10 corresponding measured clock sources 2, measured clock source 3 ... the measurement side in measured clock source 10
Method is as measured clock source 1, simply time of measuring selection in the morning 6：02nd, morning 6：03rd ... morning 6：10.This side
Method is also an advantage that：The calibrating of many N=10 platform clock sources is completed in a short time.
The time T of sampling for " my god ", calculate measured clock source stability, had according to formula (2)：
(Δ f/f) i=(Δ ti+1- Δ ti)/(t) (3)
In formula (3) because the time T of sampling for " my god " (i.e. 86400 seconds), therefore t=86400.Formula (3) is obtained
(Δ f/f) i data substitute into Allan variance calculating formula (4) and draw last measured clock source Stability index.
At least there is following beneficial effect in the application：
The application has increased temperature measurement module and tc compensation module newly on conventional atom clock technology.Newly-increased module
It can reduce or offset the shadow of whole machine output signal frequency stability caused by the change of atomic clock external working environment temperature
Ring.
It should be noted last that, above embodiment is merely illustrative of the technical solution of the present invention and unrestricted,
Although the present invention is described in detail with reference to example, it will be understood by those within the art that, can be to the present invention
Technical scheme modify or equivalent, without departing from the spirit and scope of technical solution of the present invention, it all should cover
Among scope of the presently claimed invention.
Claims (6)
1. a kind of temporal frequency apparatus for evaluating based on atomic clock, it is characterised in that the temporal frequency apparatus for evaluating includes original
Base detection module, microprocessor when sub- frequency marking, temperature measurement module, tc compensation, multichannel；
The atomic frequency standard is compensated with the temperature system successively, and atomic frequency standard output is received for the tc compensation
Frequency signal, base detection module when the temperature system compensation is with the multichannel, for temperature system compensation to be received
Frequency signal compensation after export to base detection module during the multichannel；
The temperature measurement module is connected with the atomic frequency standard, the temperature information for measuring the atomic clock external working environment；
The temperature measurement module is connected with microprocessor, for the temperature information to be sent to the microprocessor；The microprocessor
It is connected with the tc compensation.
2. temporal frequency apparatus for evaluating as claimed in claim 1, it is characterised in that the tc compensation is included outside DDS
Portion reference clock end, base is referred to during for being provided for DDS.
3. temporal frequency apparatus for evaluating as claimed in claim 2, it is characterised in that the tc compensation also includes C
Current compensation module, the C field currents compensating module includes VCSS constant current units, C enamel-covered wires and D/A modules；The VCSS
The output end of constant flow module is connected with the C enamel-covered wire, and the D/A modules of stating are connected with the VCSS constant flow modules；For
Control voltage after being changed according to the D/A modules adjusts the electric current that the C enamel-covered wire passes through.
4. temporal frequency apparatus for evaluating as claimed in claim 1, it is characterised in that base detection module is by multiple during the multichannel
Unification circuit is constituted.
5. temporal frequency apparatus for evaluating as claimed in claim 4, it is characterised in that the unification circuit includes isolation and amplified
Device, counting, latch, microprocessor, high-resolution counter, DDS module, filter shape module when walking；The isolated amplifier
Respectively with it is described walk when count, DDS module be connected, for receive measured clock source and after the isolated amplifier divide two-way
Signal, be respectively fed to it is described walk when count, DDS module；It is described walk when count successively with the latch, microprocessor, high-precision
Degree counter is connected in series；The DDS module, filter shape module and high-resolution counter are sequentially connected in series；Micro- place
Reason device is connected with DDS module, and the measured clock source is the frequency signal exported after compensating.
6. temporal frequency apparatus for evaluating as claimed in claim 5, it is characterised in that microprocessor passes through the access to latch
The frequency values in the measured clock source after being converted, and the quilt that another road isolated amplifier is sent into DDS is rewritten by command word
Survey the frequency division value of clock source frequency signal, make DDS output signals be 1Hz, filtered shaping and microprocessor control all the way ' 0 '
Or ' 1 ' signal deliver to, obtain being examined and determine the signal output with 1PPS by the control of microprocessor ' 0 ', ' 1 ' through ' with ' computing.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710093646.2A CN106940399A (en) | 2017-02-21 | 2017-02-21 | Temporal frequency apparatus for evaluating based on atomic clock |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710093646.2A CN106940399A (en) | 2017-02-21 | 2017-02-21 | Temporal frequency apparatus for evaluating based on atomic clock |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107608200A (en) * | 2017-09-25 | 2018-01-19 | 江汉大学 | A kind of space ejection type atomic clock device |
| CN109856472A (en) * | 2018-12-13 | 2019-06-07 | 江汉大学 | Catch calibrating installation in miniaturization fishpond based on multi-way detecting signal |
| CN110687555A (en) * | 2019-09-23 | 2020-01-14 | 西安空间无线电技术研究所 | Navigation satellite atomic clock weak frequency hopping on-orbit autonomous rapid detection method |
| CN111142604A (en) * | 2019-12-25 | 2020-05-12 | 兰州空间技术物理研究所 | C field circuit capable of automatically compensating temperature coefficient of rubidium clock |
| CN113108825A (en) * | 2021-03-26 | 2021-07-13 | 山东师范大学 | Atomic clock error measurement and correction method and error measurement and correction instrument |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107608200A (en) * | 2017-09-25 | 2018-01-19 | 江汉大学 | A kind of space ejection type atomic clock device |
| CN107608200B (en) * | 2017-09-25 | 2020-05-22 | 江汉大学 | Ejecting atomic clock device for space |
| CN109856472A (en) * | 2018-12-13 | 2019-06-07 | 江汉大学 | Catch calibrating installation in miniaturization fishpond based on multi-way detecting signal |
| CN110687555A (en) * | 2019-09-23 | 2020-01-14 | 西安空间无线电技术研究所 | Navigation satellite atomic clock weak frequency hopping on-orbit autonomous rapid detection method |
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| CN113108825A (en) * | 2021-03-26 | 2021-07-13 | 山东师范大学 | Atomic clock error measurement and correction method and error measurement and correction instrument |
| CN113108825B (en) * | 2021-03-26 | 2022-08-23 | 山东师范大学 | Atomic clock error measurement and correction method and error measurement and correction instrument |
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Application publication date: 20170711 |