CN218570220U - Satellite-borne low-phase-noise frequency source - Google Patents

Abstract

The utility model relates to a space-borne low-phase noise frequency source, which includes a reference source, a sampling phase detector, an expansion capture circuit, a filter circuit, a medium oscillation circuit and a coupling circuit; the output end of the reference source and the sampling phase detector The input end of the sampling phase detector is connected to the input end of the expansion capture circuit and the filter circuit, the output end of the expansion capture circuit and the filter circuit is connected to the input end of the dielectric oscillation circuit, and the output of the dielectric oscillation circuit The terminal is connected with the input terminal of the coupling circuit, and the output terminal of the coupling circuit is connected with the sampling phase detector and outputs a signal. The utility model introduces a new sampling phase detection circuit and uses sampling phase locking technology to optimize the design of the entire circuit, so as to meet the requirements of current frequency source synthesis with low phase noise, high pure frequency spectrum and high stability.

Description

A Spaceborne Low Phase Noise Frequency Source

technical field

The utility model relates to the technical field of communication, in particular to a space-borne low-phase-noise frequency source.

Background technique

With the continuous development of radar, satellite measurement and control communication technology, space exploration, and measuring instruments, the system puts forward higher requirements for performance indicators such as phase noise, spectrum purity, and frequency stability of local oscillators. Seeking lower phase noise and purer spectrum Local oscillator sources with higher stability have become the main trend in the development of microwave local oscillator sources.

The current popular frequency-division phase-locked oscillation source has achieved excellent performance, but its performance in terms of phase noise is not so satisfactory due to the limitation of its own design process level and other factors. In this scenario, the sampling phase-locked oscillator source has attracted widespread attention from engineers due to its advantages in phase noise. This technology uses a dielectric resonator voltage-controlled oscillator (DRVCO) sampling phase-locked frequency multiplier with high output frequency , with the advantages of low phase noise and small power consumption, it can be widely used in aerospace, military, satellite communication and other fields. In the past, the combination of sampling phase-locking and DRVCO to realize the high-frequency oscillation source was the solution of low-frequency phase-locking and frequency multiplication. The index did not reflect the phase noise superiority of sampling phase-locking, mainly because of the narrow pulse at that time. The formation technology is still immature, which limits the upper limit operating frequency of the sampling phase detector; however, with the development of narrow pulse forming technology, the upper limit operating frequency of the sampler is getting higher and higher, and the sampling lock designed by the current sampling phase detector The phase frequency source has been able to meet the requirements of the satellite communication platform environment with low phase noise. Therefore, how to design a low phase noise frequency source that meets the requirements of use needs to be considered at present.

It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to those of ordinary skill in the art.

Utility model content

The purpose of the utility model is to overcome the disadvantages of the prior art, provide a space-borne low-phase-noise frequency source, and solve the problems existing in the existing low-phase-noise frequency source.

The purpose of this utility model is achieved through the following technical solutions: a space-borne low-phase noise frequency source, which includes a reference source, a sampling phase detector, an expansion capture circuit, a filter circuit, a dielectric oscillation circuit and a coupling circuit; the reference source The output end of the sampling phase detector is connected to the input end of the sampling phase detector, the output end of the sampling phase detector is connected to the input end of the expansion capture circuit and the filter circuit, the output end of the expansion capture circuit and the filter circuit is connected to the input of the dielectric oscillation circuit The output end of the dielectric oscillation circuit is connected with the input end of the coupling circuit, the output end of the coupling circuit is connected with the sampling phase detector, and the signal is output.

The sampling phase detector includes a pulse forming circuit, a sampling circuit and a holding circuit; the output end of the pulse forming circuit is connected to the input end of the sampling circuit, and the output end of the sampling circuit is connected to the output end of the holding circuit.

The output terminal of the reference source is connected to the input terminal of the pulse forming circuit, the output terminal of the holding circuit is connected to the input terminals of the expansion and capture circuit and the filter circuit, and the output terminal of the coupling circuit is connected to the input terminal of the sampling circuit.

The expansion capture circuit includes an operational amplifier U4, capacitors C3 and C6 and a resistor R3 are connected between the 3rd pin and the 6th pin of the operational amplifier U4, the capacitor C3 and the resistor R3 are connected in series, the capacitor C3 and the capacitor C6 are connected in parallel, Capacitors C3 and C6 and resistor R3 form a filter circuit.

The utility model has the following advantages: a space-borne low-phase noise frequency source, by introducing a new sampling phase detection circuit, using sampling phase-locking technology to optimize the design of the entire circuit to meet the current frequency source synthesis of low phase noise, high-purity spectrum , High stability requirements.

Description of drawings

Fig. 1 is the circuit schematic diagram of the present utility model;

Fig. 2 is the circuit diagram of sampling phase detector;

Fig. 3 is a schematic diagram of the expansion capture circuit and the filter circuit.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only It is a part of the embodiments of this application, not all of them. The components of the embodiments of the application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present application provided in conjunction with the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application. Below in conjunction with accompanying drawing, the utility model is described further.

As shown in Fig. 1, the utility model relates to a kind of space-borne low-phase-noise frequency source specifically, and it comprises reference source, sampling phase detector, expansion capture circuit, filtering circuit, medium oscillation circuit and coupling circuit; The reference source The output end is connected to the input end of the sampling phase detector, the output end of the sampling phase detector is connected to the input end of the expansion capture circuit and the filter circuit, the output end of the expansion capture circuit and the filter circuit is connected to the input end of the dielectric oscillation circuit connected, the output end of the medium oscillating circuit is connected with the input end of the coupling circuit, the output end of the coupling circuit is connected with the sampling phase detector, and the signal is output.

Further, the sampling phase detector mainly includes pulse forming circuit, sampling circuit and holding circuit; the output end of the pulse forming circuit is connected with the input end of the sampling circuit, and the output end of the sampling circuit is connected with the output end of the holding circuit connect. The output terminal of the reference source is connected to the input terminal of the pulse forming circuit, the output terminal of the holding circuit is connected to the input terminals of the expansion and capture circuit and the filter circuit, and the output terminal of the coupling circuit is connected to the input terminal of the sampling circuit.

Among them, as shown in Figure 2, due to the integration of the device, the sampling phase detector is selected as the JVJQ2018 sampling phase detector. The reference signal forms a comb spectrum signal through the step tube inside the device. The base tube is compared with the RF input signal. When the RF input signal frequency is an integer multiple of the reference signal frequency, the high-frequency signal is removed through the LC filter, and a stable DC voltage signal is output from the LF output terminal. When the RF signal frequency ≠ the reference signal frequency When the signal is an integer multiple, the high-frequency signal is removed by the LC filter circuit, and the LF output terminal outputs a continuous IF signal (beat voltage), thereby realizing the sampling phase detection function.

Furthermore, the dielectric oscillation circuit uses an integrated circuit device CRO2013S-1 voltage-controlled dielectric oscillator, and the coupling circuit uses a traditional directional microstrip coupler.

As shown in Figure 3, the expansion capture circuit includes an operational amplifier U4. Capacitors C3 and C6 and a resistor R3 are connected between the third pin and the sixth pin of the operational amplifier U4. The capacitor C3 and the resistor R3 are connected in series, and the capacitor C3 and the resistor R3 are connected in series. Capacitor C6 is connected in parallel, capacitors C3 and C6 and resistor R3 form a filter circuit; the signal after sampling phase discrimination is sent to the circuit for filter amplification, and the whole circuit adopts a mature active filter circuit.

The working process of the utility model is as follows: after the reference source inputs the reference signal, the step diode of the pulse forming circuit in the sampling phase detector is driven to replace the sampling pulse of the millisecond level, and the repetition period of the pulse is completely consistent with the frequency period of the reference source signal , the sampling pulse is periodically sent to the sampling circuit of the sampling phase detector together with the radio frequency signal of the dielectric oscillation circuit obtained by the coupling circuit, and then the holding circuit holds the sampled voltage until the next cycle, when the dielectric oscillation circuit It is an integer multiple of the reference frequency and maintains strict phase synchronization. The sampling phase detector will output an error voltage to form a stable DC voltage after passing through the filter circuit and the expansion capture circuit. It will be a continuous step-like beat voltage that pulls the medium oscillating circuit until the circuit locks. In this circuit, when the frequency of the radio frequency signal output by the dielectric oscillating circuit is near a certain harmonic of the sampling pulse frequency, the dielectric oscillating circuit can be locked at a certain harmonic of the sampling pulse frequency through the control of the filter circuit and the expansion and capture circuit. on the subharmonic.

The above descriptions are only preferred implementations of the present utility model, and it should be understood that the present utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments , and can be modified within the scope of the ideas described herein by the teachings above or by skill or knowledge in the relevant art. However, changes and changes made by those skilled in the art do not depart from the spirit and scope of the utility model, and should all be within the protection scope of the appended claims of the utility model.

Claims (4)

1. A satellite-borne low-phase-noise frequency source, characterized by: the device comprises a reference source, a sampling phase discriminator, an expansion and capture circuit, a filter circuit, a dielectric oscillation circuit and a coupling circuit; the output end of the reference source is connected with the input end of the sampling phase discriminator, the output end of the sampling phase discriminator is connected with the input ends of the spread-capture circuit and the filter circuit, the output ends of the spread-capture circuit and the filter circuit are connected with the input end of the dielectric oscillation circuit, the output end of the dielectric oscillation circuit is connected with the input end of the coupling circuit, and the output end of the coupling circuit is connected with the sampling phase discriminator and outputs signals.

2. A satellite-borne low-phase-noise frequency source according to claim 1, characterized in that: the sampling phase discriminator comprises a pulse forming circuit, a sampling circuit and a holding circuit; the output end of the pulse forming circuit is connected with the input end of the sampling circuit, and the output end of the sampling circuit is connected with the output end of the holding circuit.

3. A satellite-borne low-phase-noise frequency source according to claim 2, characterized in that: the output end of the reference source is connected with the input end of the pulse forming circuit, the output end of the holding circuit is connected with the input ends of the diffusion circuit and the filter circuit, and the output end of the coupling circuit is connected with the input end of the sampling circuit.

4. A satellite-borne low-phase-noise frequency source according to claim 1, characterized in that: the amplifying and capturing circuit comprises an operational amplifier U4, capacitors C3 and C6 and a resistor R3 are connected between a No. 3 pin and a No. 6 pin of the operational amplifier U4, the capacitor C3 is connected with the resistor R3 in series, the capacitor C3 is connected with the capacitor C6 in parallel, and the capacitors C3, C6 and the resistor R3 form a filter circuit.

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