CN207216296U - A kind of constant temperature sequential generating means based on VCXO - Google Patents

Abstract

It the utility model is related to a kind of constant temperature sequential generating means based on VCXO, including VCXO modules, radiofrequency signal generation module, quantized system and servo loop module, the frequency signal of the VCXO modules output produces microwave interrogation signals through the radiofrequency signal generation module and acts on quantized system, the quantized system produces quantum frequency discrimination signal and is delivered to servo loop module, the servo loop module produces direct current voltage control signal, and feedback effect in VCXO modules, makes its output frequency change again；The quantized system includes spectrum lamp and integrated filtering resonance bubble；Also include control sequential and module, gps signal receiver, logic gate array and high-speed shutter device occurs.Constant temperature sequential generating means its internal module harmony height of the present utility model based on VCXO, different situations are can adapt to by effective SECO.

Description

A kind of constant temperature sequential generating means based on VCXO

Technical field

It the utility model is related to atomic clock technical field, and in particular to a kind of constant temperature sequential generating means based on VCXO.

Background technology

In inactive type rubidium atom frequency scale, physical system is the core component of whole atomic frequency standard, and it is steady that it provides a frequency Atomic resonance Absorption Line fixed, line width is narrower.After comprehensive modulate, the band of quartz oscillator is come from caused by electronic circuit The microwave interrogation signals of modulation act on physical system, after quantum frequency discrimination, the place by servo circuit to quantum frequency discrimination information Reason, most the output frequency of local oscillator is locked in the hyperfine 0-0 transition centers frequency of ground state of rubidium atom at last.It is existing most of Servo circuit synchronizes phase demodulation according to the comprehensive synchronous phase discrimination signal provided to quantum frequency discrimination signal, and is believed according to identified result Breath realizes that the closed loop of complete machine locks by the way of the independent voltage-controlled local oscillators of D/A, higher eventually through local oscillator output stability Frequency signal.In today of digitlization popularization, the requirement minimized plus society to atomic clock, and GPS synchronous calibrations Promote, harsher requirement is proposed to existing atomic clock, it is necessary to which servo-controlled links to be concentrated on to small place Task is completed by rational SECO on reason device.But most of existing atomic clock servo circuit part is all or module Change the situation of " individual soldier fights ".

Utility model content

The technical problems to be solved in the utility model is：It is proposed that a kind of improved constant temperature sequential based on VCXO fills Put.

The utility model is to solve the technical scheme that above-mentioned technical problem proposes to be：A kind of constant temperature sequential hair based on VCXO Generating apparatus, including VCXO modules, radiofrequency signal generation module, quantized system and servo loop module, the VCXO modules output Frequency signal produce microwave interrogation signals through the radiofrequency signal generation module and act on quantized system, the quantized system production Raw quantum frequency discrimination signal is delivered to servo loop module, the servo loop module produce direct current voltage control signal again feedback effect in VCXO modules, its output frequency is set to change；The quantized system includes spectrum lamp and integrated filtering resonance bubble；

Also include control sequential and module, gps signal receiver, logic gate array and high-speed shutter device, the GPS occurs To the control sequential module occurs for the signal output of signal receiver, and the control terminal that module occurs for the control sequential connects respectively Logic gate array and the servo loop module is connected to, signal output to the control sequential of the servo loop module occurs Device, the input of the logic gate array are connected to the output end of the servo loop module, the logic gate array it is defeated Go out end and the module feedback control high-speed shutter device occurs via the servo loop module and control sequential, the high speed is fast Door gear is suitable to by the on or off of shutter device to control light between being arranged at spectrum lamp and integrated filtering the resonance bubble By or block.

Further, in addition to voltage-controlled correcting module and gain control module, the voltage-controlled correcting module and gain control Module is successively set between the servo loop module and VCXO modules.

Further, in addition to be adapted for engagement with the temperature control modules of VCXO modules, the temperature control module contain Temperature Controlling Chip and Thermistor, the temperature control module are placed in high stability crystal oscillator VCXO.

Further, the thermistor is located among electric bridge, and when operating ambient temperature is unchanged, electric bridge is in flat Weighing apparatus, the temperature-compensated voltage value for being delivered to heating coil loop is 0, when operating ambient temperature changes, thermistor Resistance will diminish or become big, then electric bridge both ends have voltage difference, are changed into temperature-compensated voltage after Temperature Controlling Chip differential amplification Voltage source is delivered to, while exports and gives external heat wire coil loop.

The beneficial effects of the utility model are：

Constant temperature sequential generating means its internal module harmony of the present utility model based on VCXO is high, by it is effective when Sequence control can adapt to different situations.

Brief description of the drawings

The constant temperature sequential generating means of the present utility model based on VCXO is described further below in conjunction with the accompanying drawings.

Fig. 1 is the structured flowchart of the constant temperature sequential generating means based on VCXO in the utility model；

Fig. 2 is the signal transmission schematic diagram in logic gate array；

Fig. 3 is the signal period figure that frequency signal test side detects；

Fig. 4 is signal timing diagram caused by control sequential generation module；

Fig. 5 is GPS second pulse signal and the frequency signal timing diagram of VCXO modules output；

Fig. 6 is total timing diagram；

Fig. 7 is the electrical block diagram of temperature control modules；

Fig. 8 is the electrical block diagram of gain adjustment module.

Embodiment

Embodiment

According to Fig. 1, the constant temperature sequential generating means based on VCXO in the utility model, including VCXO modules, penetrate Frequency signal generator module, quantized system and servo loop module, the frequency signal of the VCXO modules output are believed through the radio frequency Number generation module produces microwave interrogation signals and acts on quantized system, and the quantized system, which produces quantum frequency discrimination signal and is delivered to, to be watched Loop module is taken, the servo loop module produces direct current voltage control signal, and feedback effect in VCXO modules, makes its output frequency again Change；The quantized system includes spectrum lamp and integrated filtering resonance bubble.

Also include control sequential and module, gps signal receiver, logic gate array and high-speed shutter device, the GPS occurs To the control sequential module occurs for the signal output of signal receiver, and the control terminal that module occurs for the control sequential connects respectively Logic gate array and the servo loop module is connected to, signal output to the control sequential of the servo loop module occurs Device, the input of the logic gate array are connected to the output end of the servo loop module, the logic gate array it is defeated Go out end and the module feedback control high-speed shutter device occurs via the servo loop module and control sequential, the high speed is fast Door gear is suitable to by the on or off of shutter device to control light between being arranged at spectrum lamp and integrated filtering the resonance bubble By or block.

Occurred on logic gate array by control sequential, produce the N number of NOT gate of odd level, its input, which receives, comes from servo The signal of loop, the high speed Shutter that its output end is fed back in the spectrum lamp module of quantized system, to control its state ' opening ' or ' pass '.

When Fig. 1 schematic diagrams are started working, it is assumed that the high speed Shutter in this moment spectrum lamp module is ' opening ' state, So, the light of spectrum lamp excitation is former in conventional atom frequency marking by being directly entered after high speed Shutter in integrated resonance optical filtering bubble In the presence of reason, the quantum frequency discrimination of quantized system is completed.The signal that quantum frequency discrimination signal obtains through servo loop is sent into gate Array, because spectrum lamp excitation light of upper moment can pass through integrated filtering resonance bubble, so the moment is through letter caused by servo loop Number it is high level ' 1 ', becomes low level ' 0 ' after odd level logic inverter, the high speed Shutter acted in spectrum lamp module, It is ' pass ' state.Circulate, ' 0 ' change that occurs ' 1 '-' 0 '-' 1 ' in the output end of logic gate array ..., lead to successively Overfrequency signal detection, we can show that corresponding time parameter delivers to control sequential and module occurs.

Odd number NOT gate is produced by microprocessor to be serially connected, can produce self-oscillation, and the circuit forms a ring Shape oscillator.It is t if the number N of NOT gate is odd number in circuit, between the mean transit delay of each gate circuit is slow, ring oscillator Caused cycle of oscillation is T.It is assumed that the initial state of certain moment A1 point is 1, then after 1 transmission delay t, A2 points are changed into 0, then pass through Cross 1 transmission delay t, A3 point and be changed into 1 ..., after the N number of transmission delay Nt of odd number, initial state ' 1 ' is changed into ' 0 '.Same reason：Just State ' 0 ' is changed into ' 1 '.Signal transmission signal is as shown in Fig. 2 can obtain：

T0=2Nt（1）

After above-mentioned ring oscillator seals in atomic clock system, Fig. 3 can be obtained.

In the signal period that Fig. 3 frequency signal test side detects

T1=2(Nt+△t) （2）

Wherein, △ t are the atomic time parameter that we need to know.Pass through formula（1）With（2）, can be derived from：

△t=（T1-T0）/2 （3）

△ t in above formula are extremely important to our lower further work expansion：According to Fig. 1 it is recognised that △ t are by measuring Subsystem and the circuit of periphery determine that and the response time of electronic circuit is very fast, generally also reached 10nS magnitudes with On, so the key for determining △ t values should be the quantized system part in Fig. 1.Obtaining formula（3）In △ t after, it is sent To control sequential generation module.

Detection produces control sequential generation module after above-mentioned time parameter △ t are obtained with each road sequential, produces three Road clock signal：Detection, modulation, synchronous phase demodulation, as shown in Figure 4.Need to determine above-mentioned tune according to time parameter △ t herein System, the frequency values of synchronous phase discrimination signal, and detection signal is then.Wherein：（1）, caused modulated signal The radiofrequency signal generation module delivered in Fig. 1, for completing " comprehensive modulation " in conventional atom clock technology；（2）, it is caused with The servo loop that the synchronous synchronous phase discrimination signal with phase of above-mentioned modulated signal is delivered in Fig. 1, for completing conventional atom clock technology In " synchronous phase demodulation " function；（3）, the caused detection signal with above-mentioned modulation, the frequency multiplication relation of synchronous phase discrimination signal 4 deliver to figure Servo loop in 1, the detection for aftermentioned each function sequential.

It is divided into four kinds of situations shown in Fig. 4：

1st, the frequency f of microwave interrogation signals is more than（It is less than）Atomic transition center frequency fo and in Atomic absorption line width scope Within when, i.e. f>fo(f<Fo), unlocked frequency signal is consistent with the frequency of modulated signal in the Fig. 4 obtained through quantum frequency discrimination, Only because atom relaxation time and phase time are delayed and the difference in phase be present.

2nd, when the frequency of microwave interrogation signals is equal to atomic transition center frequency, i.e. f=fo, obtained signal frequency is former 2 times of modulated signal, now atomic frequency standard is in the lock state, and the locking signal shown in Fig. 4 occurs；

3rd, when the frequency of microwave interrogation signals is significantly away from atomic transition center frequency, i.e. f is introduced into effective quantum mirror Within the scope of frequency Absorber Bandwidth, the signal obtained after processing will be a lasting level, and now atomic frequency standard is in lock-off State；

4th, another special situation is exactly that spectrum lamp has the process of a relaxation oscillations, now from quantized system frequency discrimination Output end can detect the irregular signal waveform of high frequency, until spectrum lamp enters normal operating conditions, and whole relaxation oscillation Process duration is by specific complete machine cold conditions or hot determines.

For these four situations, using the detection sequential of 4 multiple-frequency modulation signalsContinuous 4 rising edges as triggering Pulse, level sampling is carried out to the signal after quantum frequency discrimination respectively, and be recorded as D1, D2, D3, D4 respectively.

For the first situation, there are 3 low levels, 1 high level in 4 level of record.Servo loop is according to tradition The voltage-controlled deviation correcting technology of atomic clock, the corresponding single-point direct current of voltage-controlled correcting module acquisition sent in correction voltage signal to Fig. 1 entangle Bias-voltage acts on VCXO；

For second of situation, the level of record has relational expression：D1=D3 and D2=D4.Now servo loop will not be made For voltage-controlled correcting module, i.e. VCXO will not be by direct current correction voltage effect；

For the third situation, the level of record has relational expression：D1=D2=D3=D4.Now servo loop will send and entangle Voltage-controlled correcting module in bias-voltage signal to Fig. 1, voltage-controlled correcting module will obtain corresponding straight according to preset stepped parameter Stream gets together the lasting frequency sweep for acting on VCXO, realizing to VCXO of voltage.

For the 4th kind of situation, because this moment spectrum lamp is in relaxation oscillation process, the signal high frequency at quantum frequency discrimination It is irregular, in the data that multigroup continuous 4 sampling time sequence rising edges sample to obtain it is possible to that the first situation or second occurs Kind situation or the third situation, therefore can not be judged by sampled level, the method for solution is：Due in this link, institute What is judged is whether atomic frequency standard is in the lock state, and the 4th kind of situation substantially illustrates that atomic frequency standard is not in locking, In the detection sequential of 4 multiple-frequency modulation signal frequencies of continuous 4 rising edges triggering, can set more than one group（On continuous 4 It is one group to rise along triggering）The judgment mode of sampling, atom frequency standard locking condition adjudgement is made respectively to multigroup obtained level that samples, And multigroup judgement is done and computing, final lock-out state judged result is obtained, this makes it possible to solve the 4th kind of feelings well The problem of condition is brought.Now servo loop will not act on voltage-controlled correcting module, i.e. VCXO will not be made by direct current correction voltage With.

Corrected on GPS, according to Fig. 1, receiver obtains the signal that gps satellite is sent, and second arteries and veins is obtained after converted processing Rush signal to deliver in control sequential generation module, the frequency signal of VCXO outputs is carried out in the range of a cycle of pulse per second (PPS) The servo loop that corresponding correction value is delivered in Fig. 1 is counted and obtained, and corresponding direct current is exported by voltage-controlled correcting module and entangled Collecting voltage acts on VCXO, and corresponding sequential is as shown in Figure 5.

GPS second pulse gate signal（Width is T）In high level, after the t1 times, first arteries and veins of VCXO frequency signals The rising edge of punching, make counter Enable Pin effective, start VCXO frequency signals and count, after the T seconds, the low electricity of GPS second pulse gate It is flat not stop counting when arriving, after the t2 times, when then and the rising edge of VCXO frequency signals that arrives arrive when count Number device is closed.Here enable signal（Actual signal strobe）Time width, exactly equal to VCXO frequency signals complete cycle Number.According to above-mentioned relevant parameter：T, t1, t2, N, corresponding VCXO frequencies letter can be obtained according to traditional GPS time differences comparison technology Number correction value.Total sequential of above-mentioned 3 utility models point controls as shown in Figure 6.Enabled, low level is represented in figure with high level Represent and stop.

On temperature control modules：Contain Temperature Controlling Chip in the inside（Temperature control is used）And thermistor（Thermometric is used）.By center Processor control can be with set temperature value T, because whole temperature control modules are placed in high stability crystal oscillator VCXO (temperature control module), institute Corresponding operating ambient temperature can be set with central processing unit and obtain actual operating ambient temperature information.Its principle As shown in Figure 7.Two of which R and R1 are the resistance with identical temperature coefficient, and its resistance should select suitable with Rk.Here R1 value reflects actual working environment temperature T.Rk is a thermistor, and it is affixed on the surface of temperature control module, to perceive Actual operating ambient temperature T.Therefore when operating ambient temperature T is unchanged, electric bridge is in balance in upper figure, is delivered to heater wire The temperature-compensated voltage value on ring road is 0.Once operating ambient temperature T changes, then thermistor Rk resistance will diminish （Temperature raises）Or become big（Temperature reduces）, then be present voltage difference in electric bridge both ends, be changed into after operational amplifier A differential amplification Temperature-compensated voltage is delivered to voltage source, while exports and give traditional heating wire coil loop.The gain amplifier of whole circuit is by transporting The negative feedback resistor Rw regulations of amplifier are calculated, Rw is a digital potentiometer, is mended by adjusting Rw resistance to reach foregoing circuit Repay the factor and change function.

On gain adjustment module, the bridge temperature measurement module in Fig. 8 is consistent with above-mentioned described temperature control module principle.It is voltage-controlled Bridge thermometric in module is mainly by two resistance identicals R, a preset temperature value thermistor (temperature) sensor Ro（It is determined VCXO operating ambient temperature）And temperature-measuring thermistor Rk compositions.When VCXO operating ambient temperatures are constant, i.e. thermistor Rk Measured value is equal with preset value Ro, and now resistance bridge A, B ends output voltage difference will be 0, whole voltage-controlled module output end Uout Export as 0.When VCXO operating ambient temperatures change, then A, B end of bridge form certain voltage difference, by voltage with A3, which to be delivered to, with device A1 and A2 transmission carries out differential amplification, it is contemplated that the voltage difference after amplification must effectively can gather, so Differential amplification A3 output end adds a gain linearity regulation circuit A4.Obtained voltage difference U out and voltage-controlled correcting module After caused voltage-controlled voltage summation, VCXO modules are delivered to.

It is of the present utility model to be not limited to above-described embodiment, the technical scheme of above-mentioned each embodiment of the present utility model that This can form new technical scheme with combined crosswise, and all technical schemes formed using equivalent substitution, all fall within this practicality in addition In the protection domain of new requirement.

Claims (4)

1. a kind of constant temperature sequential generating means based on VCXO, including VCXO modules, radiofrequency signal generation module, quantized system and Servo loop module, the frequency signal of the VCXO modules output produce microwave interrogation signals through the radiofrequency signal generation module Quantized system is acted on, the quantized system produces quantum frequency discrimination signal and is delivered to servo loop module, the servo loop mould Block produces direct current voltage control signal, and feedback effect in VCXO modules, makes its output frequency change again；The quantized system includes Spectrum lamp and integrated filtering resonance bubble；

It is characterized in that：Also include control sequential and module, gps signal receiver, logic gate array and high-speed shutter device occur, To the control sequential module occurs for the signal output of the gps signal receiver, and the control of module occurs for the control sequential End is connected respectively to logic gate array and the servo loop module, the signal output of the servo loop module to the control Sequential generating means, the input of the logic gate array are connected to the output end of the servo loop module, the gate The output end of array occurs module feedback via the servo loop module and control sequential and controls the high-speed shutter device, institute State high-speed shutter device be arranged between the spectrum lamp and integrated filtering resonance bubble be suitable to by the on or off of shutter device with Control light by or block.

2. the constant temperature sequential generating means based on VCXO according to claim 1, it is characterised in that：Also include voltage-controlled amendment mould Block and gain control module, the voltage-controlled correcting module and gain control module be successively set on the servo loop module and Between VCXO modules.

3. the constant temperature sequential generating means based on VCXO according to claim 2, it is characterised in that：Also include being adapted for engagement with The temperature control module of VCXO modules, the temperature control module contain Temperature Controlling Chip and thermistor, and the temperature control module is placed in Gao Wenjing Shake in VCXO.

4. the constant temperature sequential generating means based on VCXO according to claim 3, it is characterised in that：The thermistor is located at Among electric bridge, when operating ambient temperature is unchanged, electric bridge is in balance, is delivered to the temperature-compensated voltage of heating coil loop It is worth for 0, when operating ambient temperature changes, the resistance of thermistor will diminish or become big, then electric bridge both ends have electricity Pressure difference, it is changed into temperature-compensated voltage after Temperature Controlling Chip differential amplification and is delivered to voltage source, while exports and give external heat silk thread Ring road.