CN105610439A

CN105610439A - Frequency preset circuit

Info

Publication number: CN105610439A
Application number: CN201610135318.XA
Authority: CN
Inventors: 张意
Original assignee: CHENGDU SEEKCON MICROWAVE COMMUNICATION Co Ltd
Current assignee: CHENGDU SEEKCON MICROWAVE COMMUNICATION Co Ltd
Priority date: 2016-03-10
Filing date: 2016-03-10
Publication date: 2016-05-25

Abstract

The invention provides a frequency preset circuit, comprising a main loop, a pre-locked loop and a spread spectrum module, wherein the main loop and the pre-locked loop are switched by a switch; the pre-locked loop comprises a second phase-locked loop, a second loop filter, a switch, a voltage controlled oscillator, a power divider and a frequency divider sequentially in single connection; the main loop comprises a voltage controlled oscillator, a power divider, a frequency mixer, a first phase-locked loop, a first loop filter and a switch sequentially in single connection; a direct digital frequency synthesizer is in signal connection with the first phase-locked loop; and the spread spectrum module is in signal connection with the power divider. All components and circuits are produced and assembled by adopting an advanced micro assembly process, so that the size of the circuit is greatly reduced; the frequency preset circuit has the characteristics of small size, stable performance, high index consistency and the like, meanwhile, has good input and output matching, is suitable for batch production, and greatly reduces the production cost.

Description

A kind of frequency preset circuit

Technical field

The present invention relates to frequency synthesis technique field, be specifically related to a kind of frequency preset circuit.

Background technology

In electronic warfare, radar, communication system, frequency source is widely used as local oscillator, and more and more becomes the core component in system, is directly connected to the quality of system index.

Frequency synthesizer technology is one and has highly difficult advanced circuit engineering, its range of application is very wide, comprise that communication system, navigation system, radar, space electronic technology and instrument, instrument etc. all need applying frequency source technology, and the performance indications of frequency source directly affect the performance indications of complete machine. This technology is also mainly grasped by developed country at present, therefore their electronic system performance is better, their instrument such as spectrum analyzer, signal source, vector network analyzer can be dumped to China's high price, and a key core technology that the good frequency source of performance is exactly these instrument. China, as far back as the beginning of the seventies, just has research institute to launch development work to frequency synthesis technique, and has obtained certain achievement, but because technical difficulty is large and some other reason makes several research institutes of early stage research all not adhere to getting off. To the eighties domestic whole machine study institute because of requirement of engineering, all set up one after another the development team of oneself. Although through these development team struggles of more than 20 year, in frequency source technology, China has obtained some achievements, China's frequency synthesis technique compared with developed countries, still differs far away so far.

We it has been generally acknowledged that phase noise and spurious signal all worsen with 20logN, and optimal situation is N=1, phase noise and spuious inhibition is not worsened substantially, thereby obtain optimal frequency synthesized signal. The inherent shortcoming of the aspects such as that existing wideband frequency combiner circuit exists is spuious, volume, is difficult to be widely used.

Summary of the invention

The object of the invention is to for the deficiencies in the prior art, a kind of frequency preset circuit is provided, this frequency preset circuit can address the above problem well.

For reaching above-mentioned requirements, the technical scheme that the present invention takes is: a kind of frequency preset circuit is provided, and this frequency preset circuit comprises major loop, pre-lock ring road and spread spectrum module, and switch by switch on described major loop and pre-lock ring road; Described pre-lock ring road comprises the second phaselocked loop, the second loop filter, switch, voltage controlled oscillator, power splitter and the frequency divider that signal connects successively, and described frequency divider is connected with the second phaselocked loop signal; Described major loop comprises voltage controlled oscillator, power splitter, frequency mixer, the first phaselocked loop, first ring path filter and the switch that signal connects successively, and described Direct Digital Synthesizer is connected with the first phaselocked loop signal; Described spread spectrum module is connected with power splitter signal; The pre-lock ring of switch connection road, input signal is inputted and is passed through pre-lock ring road from the second phaselocked loop and forms feedback signal, and voltage controlled oscillator is locked in advance required frequency by described feedback signal; Change-over switch is connected major loop, it is phase-locked that the signal that the described feedback signal of voltage controlled oscillator output is exported with Direct Digital Synthesizer after by power splitter and frequency mixer output carries out 1:1, obtain the ultralow frequency signal of making an uproar mutually, by exporting after spread spectrum module extension frequency.

The advantage that this frequency preset circuit has is as follows:

(1) all parts and circuit all adopt advanced micro-packaging technology to produce assembling, greatly reduce circuit size, have that volume is little, stable performance, indicator consilience high, there is good input-output adapt ation simultaneously, be applicable to mass production, production cost reduces greatly, is applicable in all kinds of microwave systems such as radar, electronic countermeasure, satellite communication;

(2) realize 2GHz ~ 20GHz broadband 1:1 phase demodulation frequency and synthesized, obtained the ultralow frequency signal of making an uproar mutually, can be good at working frequency range internal stability, operating temperature range is wide, has wide application prospect.

Brief description of the drawings

Accompanying drawing described herein is used to provide further understanding of the present application, form the application's a part, in these accompanying drawings, represent same or analogous part with identical reference number, the application's schematic description and description is used for explaining the application, does not form the improper restriction to the application. In the accompanying drawings:

Fig. 1 is schematic diagram of the present invention.

Wherein: 1, the second phaselocked loop; 2, the second loop filter; 3, frequency divider; 4, switch; 5, voltage controlled oscillator; 6, power splitter; 7, spread spectrum module; 8, first ring path filter; 9, the first phaselocked loop; 10, frequency mixer; 11, Direct Digital Synthesizer.

Detailed description of the invention

For making the application's object, technical scheme and advantage clearer, below in conjunction with drawings and the specific embodiments, the application is described in further detail.

In the following description, quoting of " embodiment ", " embodiment ", " example ", " example " etc. shown to embodiment or the example so described can comprise special characteristic, structure, characteristic, character, element or limit, but be not that each embodiment or example must comprise special characteristic, structure, characteristic, character, element or limit. In addition, reuse phrase " according to the application embodiment " and, although be likely to refer to identical embodiment, not must refer to identical embodiment.

For the sake of simplicity, omitted and well known to a person skilled in the art some technical characterictic in below describing.

According to the application embodiment, a kind of frequency preset circuit is provided, as shown in Figure 1, comprise major loop, pre-lock ring road and spread spectrum module 7, switch by switch 4 on described major loop and pre-lock ring road; Described pre-lock ring road comprises the second phaselocked loop 1, the second loop filter 2, switch 4, voltage controlled oscillator 5, power splitter 6 and the frequency divider 3 that signal connects successively, and described frequency divider 3 is connected with the second phaselocked loop 1 signal; Described major loop comprises voltage controlled oscillator 5, power splitter 6, frequency mixer 10, the first phaselocked loop 9, first ring path filter 8 and the switch 4 that signal connects successively, and described Direct Digital Synthesizer 11 is connected with the first phaselocked loop 9 signals; Described spread spectrum module 7 is connected with power splitter 6 signals; Switch 4 is connected pre-lock ring road, and input signal is inputted and passed through pre-lock ring road from the second phaselocked loop 1 and forms feedback signal, and voltage controlled oscillator 5 is locked in advance required frequency by described feedback signal; Change-over switch 4 is connected major loop, the described feedback signal that voltage controlled oscillator 5 is exported by 10 outputs of power splitter 6 and frequency mixer after and the signal exported of Direct Digital Synthesizer 11 to carry out 1:1 phase-locked, obtain the ultralow frequency signal of making an uproar mutually, by exporting after spread spectrum module 7 extension frequencies.

According to the application embodiment, it is the standardized module of 50 ohm that the second phaselocked loop 1, the second loop filter 2, voltage controlled oscillator 5, power splitter 6, frequency divider 3, frequency mixer 10, the first phaselocked loop 9, first ring path filter 8, Direct Digital Synthesizer 11 and spread spectrum module 7 all adopt input, output-resistor.

According to the application embodiment, the second phaselocked loop 1, the second loop filter 2, switch 4, voltage controlled oscillator 5, power splitter 6, frequency divider 3, frequency mixer 10, the first phaselocked loop 9, first ring path filter 8, Direct Digital Synthesizer 11 and spread spectrum module 7 all adopt advanced micro-packaging technology to assemble.

The above embodiment only represents several embodiment of the present invention, and it describes comparatively concrete and detailed, but can not be interpreted as limitation of the scope of the invention. It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection domain of the present invention. Therefore protection scope of the present invention should be as the criterion with described claim.

Claims

1. a frequency preset circuit, is characterized in that: comprise major loop, pre-lock ring road and spread spectrum module (7), switch by switch (4) on described major loop and pre-lock ring road; Described pre-lock ring road comprises the second phaselocked loop (1), the second loop filter (2), switch (4), voltage controlled oscillator (5), power splitter (6) and the frequency divider (3) that signal connects successively, and described frequency divider (3) is connected with the second phaselocked loop (1) signal; Described major loop comprises voltage controlled oscillator (5), power splitter (6), frequency mixer (10), the first phaselocked loop (9), first ring path filter (8) and the switch (4) that signal connects successively, and described Direct Digital Synthesizer (11) is connected with the first phaselocked loop (9) signal; Described spread spectrum module (7) is connected with power splitter (6) signal; Switch (4) is connected pre-lock ring road, and input signal is inputted and passed through pre-lock ring road from the second phaselocked loop (1) and forms feedback signal, and voltage controlled oscillator (5) is locked in advance required frequency by described feedback signal; Change-over switch (4) is connected major loop, the described feedback signal of voltage controlled oscillator (5) output by power splitter (6) and frequency mixer (10) output afterwards and the signal exported of Direct Digital Synthesizer (11) to carry out 1:1 phase-locked, obtain the ultralow frequency signal of making an uproar mutually, by exporting after spread spectrum module (7) extension frequency.

2. frequency preset circuit according to claim 1, is characterized in that: it is the standardized module of 50 ohm that described the second phaselocked loop (1), the second loop filter (2), voltage controlled oscillator (5), power splitter (6), frequency divider (3), frequency mixer (10), the first phaselocked loop (9), first ring path filter (8), Direct Digital Synthesizer (11) and spread spectrum module (7) all adopt input, output-resistor.

3. frequency preset circuit according to claim 1, is characterized in that: described the second phaselocked loop (1), the second loop filter (2), switch (4), voltage controlled oscillator (5), power splitter (6), frequency divider (3), frequency mixer (10), the first phaselocked loop (9), first ring path filter (8), Direct Digital Synthesizer (11) and spread spectrum module (7) all adopt advanced micro-packaging technology to assemble.