CN205490488U - By ejector half rubidium atomic frequency standard - Google Patents

Abstract

The utility model relates to an atomic frequency standard technical field especially relates to a by ejector half rubidium atomic frequency standard. Including the user terminal module, synthesize the voltage -controlled crystal oscillator of module and electricity connection in proper order, buffer, radio frequency doubling of frequency module, microwave doubling of frequency module, the physical unit, servo circuit, servo circuit is including the shaping circuit module of electricity connection in proper order, the phase detection module, integrating circuit, adc and data processing module, the physical unit is connected with shaping circuit module input electricity with the alternating current signal output of synthesizing the module, data processing module's the output and the output of radio frequency doubling of frequency module all are connected with user terminal module electricity. Servo circuit inputs the module to user terminal with the frequency stability of frequency scale, and convenience of customers knows the operating condition stability of frequency scale. In addition, synthesize the module and adopt direct digital formula frequency synthesizer to replace traditional varactor diode modulated circuit, do not receive influence of temperature for atomic frequency standard has higher stability.

Description

A kind of inactive type rubidium atom frequency scale

Technical field

This utility model relates to Technology of Atomic Frequency Standards field, particularly relates to a kind of inactive type rubidium atom frequency scale.

Background technology

Traditional inactive type rubidium atom frequency scale is made up of physical location and electronic circuit two large divisions, and wherein physical location includes the compositions such as spectral lamp, integrated filtering resonance bubble, microwave cavity, photodetector, C field, magnetic cup；Electronic circuit includes integration module, VCXO, isolated amplifier, radio frequency times frequency module, microwave multiple-frequency module and servo circuit etc..Physical system provides quantum frequency discrimination benchmark, and electronic circuit provides microwave interrogation signals and frequency locking function, is locked on the Atomic Absorption peak of physical system by the output frequency of VCXO.

Atomic frequency standard be widely used in satellite location, navigate with communicate, the field such as instrument and meter and astronomy, this is accomplished by atomic frequency standard all higher precision and degree of stability, the degree of stability of its duty can not be monitored by traditional atomic frequency standard, is unfavorable for the maintenance of atomic frequency standard.Additionally, due to have employed capister modulation circuit in tradition rubidium frequency standard, capister is temperature sensing element, and when variation of ambient temperature, the amplitude inevitably resulting in square wave frequency modulation changes, thus affects the degree of stability of rubidium frequency standard.

Utility model content

The purpose of this utility model is to provide a kind of inactive type rubidium atom frequency scale, and it has a preferable degree of stability, and is easy to user and is monitored the degree of stability of its duty.

nullThe technical solution of the utility model is: a kind of inactive type rubidium atom frequency scale，Including integration module and the VCXO that is sequentially connected electrically、Isolated amplifier、Radio frequency times frequency module、Microwave multiple-frequency module、Physical location and servo circuit，Described servo circuit outfan is connected with VCXO，The input of described integration module is connected with isolated amplifier outfan，The outfan of integration module is connected with radio frequency times frequency module and servo circuit respectively，Also include the user terminal module for showing frequency marking relevant information、The first wireless communication module and the second wireless communication module for radio communication，Described servo circuit includes the shaping circuit module being sequentially connected electrically、Phase detecting module、Integrating circuit、Analog-digital converter and data processing module，The AC signal outfan of described physical location and integration module electrically connects with shaping circuit module input，The outfan of described isolated amplifier and the outfan of data processing module are connected with user terminal module by the first wireless communication module and the second wireless communication module respectively.

Further, described shaping circuit module includes the first shaping circuit and the second shaping circuit, the AC signal outfan of described integration module and the electrical connection of the first shaping circuit input, the AC signal outfan of described physical location and the electrical connection of the second shaping circuit input, described first shaping circuit and the second shaping circuit outfan all electrically connect with phase detecting module.

Further, described integration module includes phase accumulator, Direct Digital Synthesizer and the low pass filter being sequentially connected with, the input of described phase accumulator is connected with keying FM signal outfan and setpoint frequency signal output part, the clock signal input terminal of described Direct Digital Synthesizer is connected with VCXO clock signal output terminal, and described low pass filter outfan is connected with radio frequency times frequency module and servo circuit respectively.

Further, described physical location includes integrated filtering resonance bubble, is filled with buffer gas in described integrated filtering resonance bubble.

Further, described Direct Digital Synthesizer uses AD9832 chip.

The beneficial effects of the utility model are: the two-way AC signal that integration module and physical location light cell produce, respectively by shaping circuit shaping, obtain along reasonable burst pulse, it is then fed into phase detecting circuit and carries out phase demodulation, obtain the pulse signal of corresponding two signal phase differences, corresponding DC voltage is become through integration, a series of frequency difference Value Data can be obtained after analog digital conversion and data process, such that it is able to calculate frequency stability, the frequency stability of frequency marking is sent to user terminal module by wireless communication module, user can be facilitated to understand the stable working state degree of frequency marking, can also realize remotely monitoring simultaneously, even if user is the most at the scene, also will appreciate that the enforcement operating mode of frequency marking.It addition, integration module uses Direct Digital Synthesizer to replace traditional capister modulation circuit, it is not influenced by temperature so that atomic frequency standard has higher degree of stability.

Accompanying drawing explanation

Fig. 1 is this utility model catenation principle block diagram；

Fig. 2 is servo circuit internal module annexation figure；

Fig. 3 is the internal sequential chart of servo circuit；

Fig. 4 is the internal annexation figure of integration module；

In figure: 1 VCXO, 2 isolated amplifiers, 3 radio frequency times frequency modules, 4 microwave multiple-frequency modules, 5 physical locations, 6 servo circuits, 601a the first shaping circuit, 601b the second shaping circuit, 602 phase detecting module, 603 integrating circuit, 604 analog-digital converters, 605 data processing modules, 7 synthetic circuits, 701 phase accumulators, 702 memorizeies, 703 digital to analog converters, 704 low pass filters, 8 user terminal modules, 9 first wireless communication modules, 10 second wireless communication modules.

Detailed description of the invention

In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with drawings and Examples, this utility model is further elaborated.Specific embodiment described herein, only in order to explain this utility model, is not used to limit this utility model.As long as just can be mutually combined additionally, technical characteristic involved in each embodiment of this utility model disclosed below does not constitutes conflict each other.

As it is shown in figure 1, the inactive type rubidium atom frequency scale that this utility model uses includes integration module 7, user terminal module the 8, first wireless communication module the 9, second wireless communication module 10 and VCXO 1, isolated amplifier 2, radio frequency times frequency module 3, microwave multiple-frequency module 4, physical location 5 and the servo circuit 6 being sequentially connected electrically.Spectral lamp, integrated filtering resonance bubble, microwave cavity, photodetector, C field, magnetic cup etc. are included again in physical location 5.Greatly reduce for making Doppler widen, in integrated filtering resonance bubble, be filled with buffer gas, the buffer gas being filled with in the present embodiment usually noble gas or make the non-inert gas of elastic collision with 87Rb atom.

As in figure 2 it is shown, servo circuit 6 includes shaping circuit module, phase detecting module 602, integrating circuit 603, analog-digital converter 604 and the data processing module 605 being sequentially connected electrically.Shaping circuit module includes again the first shaping circuit 601a and the second shaping circuit 601b.Wherein, the AC signal outfan of integration module 7 and the electrical connection of the first shaping circuit 601a input, described physical location 5 photronic AC signal outfan and the electrical connection of the second shaping circuit 601b input, the first shaping circuit 601a and the second shaping circuit 601b outfan all electrically connect 602 with phase detecting module.

It is illustrated in figure 3 the signal timing diagram before and after servo circuit 7 processes.Integration module 7 and physical location 5 light cell output two-way AC signal process to shaping circuit module, obtain along reasonable burst pulse, it is then fed in phase detecting module 602 carrying out phase demodulation process, obtain the pulse signal of corresponding two signal phase differences, through a few divisional processing of integrating circuit, become corresponding DC voltage, this DC voltage is carried out analog digital conversion, finally carry out data process, rectify a deviation voltage and the stability of frequency can be obtained.Correction voltage is sent to VCXO 1, the frequency stability of frequency marking is sent to user terminal module 8 by the second wireless communication module 10, simultaneously, isolated amplifier 2 outputs it signal by the first wireless communication module 9 and is sent to user terminal module 8, and user can be allowed to understand the steadiness of current atom frequency marking complete machine.User terminal module 8 can be mobile phone, panel computer, laptop computer etc., and user can realize the long-range monitoring to frequency marking, even if user is the most at the scene, also will appreciate that the enforcement operating mode of frequency marking.

Concrete integration details is as follows: the present embodiment is as a example by 8 analog-digital converter 604 samplings, the numerical range that it can represent on digital signal is 0-255, generally may require that user gives a calibration value (such as 122) before testing, it is used for defining analog digital conversion digital signal value corresponding during 0 degree of phase place, and the analog digital conversion digital signal value corresponding to phase value that can be easily computed corresponding-1800 ,+1800 accordingly is 61 and 186.If so defining, then minimum resolution is about about 30.With the calibration value 122 of this analog-digital converter, as a example by acquisition time is 10 seconds, calculates during actual samples and once need 1000 data.We take collection data in the 1st, the 101st, the 201st ... voltage value V_i, it is translated into phase valueConcrete conversion formula is:

3600 complete number of cycles in wherein N is 1000 data of i-th, V_iThe analog digital conversion numerical value (having positive and negative dividing) corresponding to the i-th-1 1000 data moment, φ is deducted for 1000 data moment of i-th_iBe total phase value that 1000 data moment of required i-th are experienced, then 1000 data time difference frequencies of i-th are according to f_iFor:

In the method, it is possible to obtain a series of frequency difference Value Data f_i.There is corresponding f_iValue, is substituted into below equation calculating frequency stability, and result is delivered to user terminal module 8, and user can be allowed to understand current atom frequency marking complete machine stability situation:

${\mathrm{H\σ}}_f(3,\mathrm{\τ})=\sqrt{\frac{1}{6(m-2)}\underset{i=1}{\overset{m-2}{\Σ}}{(f_{i+2}-2f_{i+1}+f_i)}^2}$

Wherein τ is sample time, f_iProcess the frequency-splitting obtained for above-mentioned data, m is pendulous frequency.

It is illustrated in figure 4 the inside annexation figure of integration module 7.Integration module 7 is mainly made up of the phase accumulator 701 being sequentially connected with, Direct Digital Synthesizer and low pass filter 704.Wherein the Direct Digital Synthesizer in the present embodiment uses AD9832 chip, and it includes memorizer 702 and digital to analog converter 703.The reference source of Direct Digital Synthesizer is the frequency signal that isolated amplifier 2 inputs to integration module 7.The input input of phase accumulator 701 has keying FM signal (i.e. 79HZ modulated square wave signal) and frequency setting signal.Phase accumulator 701 exports two frequency value F 0, F1 is saved in memorizer 702, when the FSELECT port of AD9832 chip has square-wave signal to input (level rising edge or trailing edge conversion), the IOUT end of AD9832 chip will read the value of F1 or F0 the most respectively as output from memorizer 702, and the phase place of signal can be kept unchanged.Owing to the digital to analog converter 703 of AD9832 chip is converted to several more, further increase the quality of output signal.And make an uproar mutually to improve, suppress the technical specification such as spuious, the present embodiment accesses low pass filter 704 and exports below.

The above, detailed description of the invention the most of the present utility model, it is noted that any those of ordinary skill in the art in the technical scope disclosed by this utility model, the change that can readily occur in or replacement, all should contain within protection domain of the present utility model.

Claims (5)

1. an inactive type rubidium atom frequency scale, including integration module (7) and be sequentially connected electrically VCXO (1), isolated amplifier (2), radio frequency times frequency module (3), microwave multiple-frequency module (4), physical location (5) and servo circuit (6), described servo circuit (6) outfan with VCXO (1) connects, the input of described integration module (7) and isolated amplifier (2) Outfan connects, the outfan of integration module (7) respectively with radio frequency times frequency module (3) and watching Take circuit (6) to connect, it is characterised in that: also include the use for showing frequency marking relevant information Family terminal module (8), for first wireless communication module (9) of radio communication and the second nothing Line communication module (10), described servo circuit (6) includes the shaping circuit mould being sequentially connected electrically Block, phase detecting module (602), integrating circuit (603), analog-digital converter (604) and Data processing module (605), described physical location (5) exchanges letter with integration module (7) Number outfan electrically connects with shaping circuit module input, described isolated amplifier (2) defeated Go out the outfan of end and data processing module (605) respectively by the first wireless communication module (9) It is connected with user terminal module (8) with the second wireless communication module (10).

2. a kind of inactive type rubidium atom frequency scale as claimed in claim 1, it is characterised in that: Described shaping circuit module includes the first shaping circuit (601a) and the second shaping circuit (601b), The AC signal outfan of described integration module (7) and the first shaping circuit (601a) input End electrical connection, the AC signal outfan of described physical location (5) and the second shaping circuit (601b) Input electrically connects, described first shaping circuit (601a) and the second shaping circuit (601b) Outfan all electrically connects with phase detecting module (602).

3. a kind of inactive type rubidium atom frequency scale as claimed in claim 1, it is characterised in that: Described integration module (7) includes phase accumulator (701), the Direct Digital being sequentially connected with Frequency synthesizer and low pass filter (704), the input of described phase accumulator (701) It is connected with keying FM signal outfan and setpoint frequency signal output part, described Direct Digital The clock signal input terminal of frequency synthesizer is connected with VCXO clock signal output terminal, described Low pass filter (704) outfan respectively with radio frequency times frequency module (3) and servo circuit (6) Connect.

4. a kind of inactive type rubidium atom frequency scale as claimed in claim 1, it is characterised in that: Described physical location (5) includes integrated filtering resonance bubble, fills in described integrated filtering resonance bubble There is buffer gas.

5. a kind of inactive type rubidium atom frequency scale as claimed in claim 3, it is characterised in that: Described Direct Digital Synthesizer uses AD9832 chip.