RU4872U1 - FREQUENCY STANDARD BASED ON QUANTUM DISCRIMINATOR - Google Patents

Abstract

A frequency standard based on a quantum discriminator comprising a crystal oscillator, a frequency multiplier, a harmonic generator, a quantum discriminator, a selective low-frequency amplifier, a synchronous detector and an integrating amplifier, the output of which is connected to the input of the crystal oscillator, the output of which is connected to the input of the frequency synthesizer, the first the output of which is connected to the second input of the harmonic generator, characterized in that a key programmable modulator is introduced, the input of which is connected to the second direct output of the frequency synthesizer, and the output with the second input of the synchronous detector and the input of the frequency synthesizer.

Description

FREQUENCY STANDARD BASED ON QUANTUM DISCRIMINATOR

Suggested Model 0 | It can be used in rubidium reference frequency sensors.

There are well-known Aetotz standards, which are used in rubidium reference frequency sensors, for example, Frequency and time standards based on quantum generators and discriminators of nodes edited by B.P. Fateev, M ,, Sov.radio, 1978,. Grigoryyats, etc., Quantum standards Frequencies, Science, 1967, pp. 288.

A disadvantage of analogues is a significant dependence of frequency instability on the parameters of the modulus of the signal.

The closest but technical essence to the proposed one is the Standards of frequency and time on the basis of quantum generators and discriminators under the editorship of B.P. Shateev, M ,, Sov.radio, 1978, p. 304, adopted as a prototype

The structural diagram of the prototype investment in figure 1, where indicated;

I - synthesizer with frequency shift keying,

Z is a harmonic generator,

3- frequency multiplier,

4-crystal oscillator,

5-quantum discriminator,

6-modulating low-frequency generator,

7- integrating amplifier,

8- selective low-frequency amplifier,

9-synchronous detector.

The prototype contains a series-connected frequency synthesizer I, harmonics generator Z quantum discriminator 5, selective low-frequency amplifier 8, synchronous detector 9, integrating amplifier 7, crystal oscillator. 4, the frequency multiplier 3, the output of which is connected to another input of the harmonic generator 2, or the output of the key programmable modulator b is connected to the corresponding inputs of the frequency multiplier 3 and the synchronous detector 9. The common output point of the crystal oscillator 4 and the input of the frequency multiplier 3 is connected to the input of the frequency synthesizer with frequency manipulation.

The prototype works as follows.

The frequency of the signal of the crystal oscillator 4 J- located in the auto-tuning ring according to the quantum discriminator 5, using the frequency multiplier 3 is multiplied by / t / time. The frequency signal A // from the output of the multiplier 3 is applied to the harmonic generator 2,

At the same time, a signal with a frequency of s is supplied to the harmonic generator 2. from synthesizer I. Harmonic generator 2 generates a frequency signal (), where / tjt is the frequency multiplier of the signal in harmonics generator 2,

The signal of the harmonic generator 2 is fed to a quantum discriminator 5 and creates a microwave field in it, the frequency of which is compared with the frequency of the spectral absorption line of the hyperfine transition (STF) of rubidium atoms.

The quantum discriminator 5 operates on the principle of double radio resonance, for the indication of which and the creation of a self-tuning signal of the crystal oscillator 4, phase modulation of the frequency multiplier 3 is used with the help of a) low-frequency modulating generator b.

The signal of the generator b is supplied simultaneously to the frequency multiplier 3 and to the input of the synchronous detector 9. The signal from the output of the quantum discriminator 5, the magnitude and sign of which depends on the frequency detuning (, 1 s ° frequency of the STP of the quantum discriminator, is amplified by a selective amplifier 8, is input to another input of the synchronous detector 9 5,

Synchronous detector 9 generates a direct current error signal, which, through the intrinsic amplifier 7, adjusts the frequency of the crystal oscillator 3 to the highly stable frequency of the STP quantum discriminator 5 in the considered auto-tuning ring.

The disadvantage of the prototype is the large dependence of the frequency instability of the crystal oscillator 4 in the self-tuning ring according to the quantum discriminator 5 on the phase modulation parameters: the instability of the amplitude, the frequency of the modulating generator b and its cliff factor on the one hand, and the instability of the frequency deviation and its clear factor in the frequency multiplier 3 itself.

For the transformer of the indicated 1 redistributor in devices ©, containing sequentially compatible frequency synthesizer with frequency manipulation, a harmonic generator, a quantum discriminator, a selective low-frequency amplifier, an in-line detector, an integrating irium amplifier, a crystal oscillator, a frequency multiplier, the output of which is connected to the other input of the harmonic generator, and the common exit point of the crystal oscillator and the input of the multiplier whose frequency is connected to one of the inputs of the frequency synthesizer, a key programmable modulator is introduced, the output to torogo odiovremenno coupled to corresponding inputs of a synchronous detector and a frequency synthesizer with frequency shift keying, the other output is connected to the input of the programmable key modulator.

The structural diagram of the proposed frequency standard with a small effect of the modulation parameters on the frequency instability of the crystal oscillator in the auto-tuning ring by the quantum discriminator is shown in figure 2, where it is indicated:

1-5 and 7-9 - as in the prototype,

3.

The frequency eod standard compares the frequency synthesizer with a frequency interface JSCHI I, harmonic generator 2, quantum discriminator 5, selective low-frequency amplifier 8, synchronous detector 9, integrating amplifier 7, crystal oscillator 4, the output of which is connected simultaneously with one of the inputs of the synthesizer frequency I and through a frequency multiplier by the 3rd other input of the harmonic generator 2, B1, the input of the key programmable modulator b is connected simultaneously with the corresponding inputs of the siphon detector 9 and the frequency synthesizer s I, one of the outputs of which is connected to the input of the key programmable modulator b,

The proposed frequency standard works as follows.

A quartz oscillator 4 operates in a frequency-locked loop according to the highly stable frequency of the absorption line of the quantum discriminator 5. This ring is formed by randomly connected links from a multiplier 3, a harmonic generator 2, a quantum discriminator 5, a selective amplifier 8, a siphon detector 9, an integrating amplifier 7 and a crystal oscillator 4.

Synthesizer I is used to convert the multiplied frequency of the crystal oscillator to the frequency of the spectral absorption line of the quantum discriminator 5,

To generate a self-tuning signal, the frequency of the synthesizer I is frequency-shifted using the key programmable modulator 6, which provides output voltage in the form of a square wave, which is independent of the instability of the modulator and synthesizer parameters.

This allows you to weaken the influence of the phase modulation parameters on the frequency instability of the quartz gtarator 4 in the auto-tuning ring, reduce the dimensions of the frequency standard and increase the reliability of its operation.

Thus, the “standard frequency standard” provides increased frequency stability and reliability by weakening the influence of the parameters of the phase ® mods and has novelty, utility and meets the requirements of the useful models.

Patent holder - Voronezh Research Institute of Communications.

Deputy Chief Engineer Yu.V. Snowy

Claims (1)

A frequency standard based on a quantum discriminator comprising a crystal oscillator, a frequency multiplier, a harmonic generator, a quantum discriminator, a selective low-frequency amplifier, a synchronous detector and an integrating amplifier, the output of which is connected to the input of the crystal oscillator, the output of which is connected to the input of the frequency synthesizer, the first the output of which is connected to the second input of the harmonic generator, characterized in that a key programmable modulator is introduced, the input of which is connected to the second direct output of the frequency synthesizer, and the output with the second input of the synchronous detector and the input of the frequency synthesizer.