CN202374217U - Frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting PCB (Printed Circuit Board) technology - Google Patents
Frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting PCB (Printed Circuit Board) technology Download PDFInfo
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- CN202374217U CN202374217U CN2011205045034U CN201120504503U CN202374217U CN 202374217 U CN202374217 U CN 202374217U CN 2011205045034 U CN2011205045034 U CN 2011205045034U CN 201120504503 U CN201120504503 U CN 201120504503U CN 202374217 U CN202374217 U CN 202374217U
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- feedthrough capacitor
- yig
- oscillating unit
- tuned oscillator
- capacitor
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Abstract
The utility model discloses a frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting the PCB (Printed Circuit Board) technology. The YIG tuned oscillator comprises a sealed magnet body, an oscillation unit and an external power supply as well as a first straight-through capacitor, a second straight-through capacitor and an SMA (Shape Memory Alloy) output interface which are arranged on a casing of the sealed magnet body; the oscillation unit comprises a printed circuit board as well as a microwave transistor, an emitting electrode feeding circuit, a grounding capacitor, a YIG coupling unit, a collecting electrode feeding circuit and an output circuit which are mounted on the printed circuit board; the grounded grounding capacitor is connected between the emitting electrode feeding circuit and YIG coupling unit; and the grounding capacitor is composed of copper foil on the printed circuit board. The tuned oscillator provided by the utility model solves the problem that impedance discontinuity, oscillation stop and the like are caused when a lumped element is adopted in a radio-frequency channel.
Description
Technical field
The utility model relates to a kind of spectrum measuring device, and adopts the yig tuned oscillator of PCB technology.
Background technology
Spectrum analyzer is the indispensable means that radio signal is measured, and is the common tool of being engaged in the electronic product research and development, producing, check, and uses very extensively.
Spectrum analyzer is divided into scan-type spectrum analyzer and real-time formula spectrum analyzer, and the scan-type spectrum analyzer is mainly used in the spectrum analysis of continuous signal and periodic signal, and its basic principle structure chart is as shown in Figure 1; Spectrum analyzer 1 comprises RF signal input end 11, attenuator 12, frequency mixer 13; Amplifier 14, filter 15, wave detector 16; Local oscillator 17, sweeping generator 18 and display 19 etc., its basic principle is the method through scanning local oscillator 17; The signal that radio-frequency input signals and local oscillator 17 produced carries out mixing, and the intermediate-freuqncy signal that obtains is amplified, after the Filtering Processing, is output as vision signal through wave detector 16; Pass through various computings again, final measurement is exported on display 19.
It is thus clear that local oscillator plays an important role in the scan-type spectrum analyzer.In the prior art, adopt the local oscillator of yig tuned oscillator as the scan-type spectrum analyzer, yig tuned oscillator is called for short YTO more; The power module that it generally includes oscillating circuit, the closed magnet of sealing scanning magnetic field can be provided and supply power for oscillating circuit; Wherein the basic principle structure chart of oscillating circuit 2 is as shown in Figure 2, and it comprises microwave transistor 25, emitter feed circuit 21, collector electrode feed circuit 23, coupled structure 22, ground capacity 24 and output circuit 26, and wherein microwave transistor 25 is an oscillating tube; After powering on for oscillating tube; All contain abundant harmonic component in the kick of voltage and the fluctuation of electric current, the YIG bead in the coupled structure 22 produces resonance to harmonic component wherein, through suitable dc point is set for feed circuit; Make entire circuit be in unsteady state; Thereby realize vibration, output circuit 26 is used for oscillator signal is cushioned amplification, finally realizes the output of signal.Wherein ground capacity 24 is used to realize the ground connection of radio frequency path.
In the prior art, the oscillating circuit among the YTO is to adopt printed circuit board technology to process, but its critical component ground capacity adopts lamped element to realize more; Because in radio circuit, the parasitic capacitance in the lamped element encapsulation, lead-in inductance, series resistance etc. can not look like in low-frequency channel, to be left in the basket, they can change with frequency change; Even one or more resonance points appear, and causing the impedance sudden change, the failure of oscillation phenomenon appears; So the operating frequency of this type of YTO is lower, frequency band is narrower.
Summary of the invention
In order to solve the problem that exists in the prior art, the utility model provides a kind of yig tuned oscillator of the PCB of employing technology, and have the spectrum measuring device of this yig tuned oscillator.
The utility model provides a kind of yig tuned oscillator of the PCB of employing technology; Comprise sealing magnet, oscillating unit, an external power supply and be installed in one first feedthrough capacitor, second feedthrough capacitor and the SMA output interface on the shell of described sealing magnet; Described oscillating unit comprises a pcb board; And be installed in a microwave transistor on the described pcb board, an emitter feed circuit, a ground capacity, a YIG coupling unit, a collector electrode feed circuit, an output circuit; Described external power supply is installed in the outside of described sealing magnet; Its positive-negative output end is connected with second feedthrough capacitor with described first feedthrough capacitor respectively; Its earth terminal is connected with the sealing magnet; Described oscillating unit is installed in the inside of described sealing magnet, and the positive-negative power input of described oscillating unit is connected with second feedthrough capacitor with described first feedthrough capacitor respectively, and the output of described oscillating unit is connected with described SMA output interface; Described emitter feed circuit and YIG coupling unit are connected in series between the emitter of negative supply input and described microwave transistor of described oscillating unit successively; Described collector electrode feed circuit is connected in series between the collector electrode of positive supply input and described microwave transistor of described oscillating unit, and described output circuit is connected in series between the output of collector electrode and described oscillating unit of described microwave transistor, between described emitter feed circuit and described YIG coupling unit; Be connected with the ground capacity of a ground connection, described ground capacity is to be made up of the Copper Foil on the pcb board.
In the described tuned oscillator of the utility model, the electric capacity span of described ground capacity can also be 1pF-5pF.
In the described tuned oscillator of the utility model, described ground capacity can also be made up of the rectangle Copper Foil.
In the described tuned oscillator of the utility model, described ground capacity can also be made up of fan-shaped Copper Foil.
In the described tuned oscillator of the utility model, described ground capacity can also be made up of the interdigitated Copper Foil.
In the described tuned oscillator of the utility model, between the positive output end of described external power supply and described first feedthrough capacitor, can also be connected with the filter capacitor of a ground connection, its electric capacity span is 100uF-470uF.
In the described tuned oscillator of the utility model, the electric capacity span of described filter capacitor can also be 220uF-330uF.
In the described tuned oscillator of the utility model, the capacitance of described filter capacitor can also be 220uF.
In the described tuned oscillator of the utility model, the line of the long axis of symmetry of described SMA output interface and described first feedthrough capacitor and described second feedthrough capacitor can also be at angle, and this angle span is 20 degree-60 degree.
And the utility model has also proposed a kind of spectrum measuring device, and it has aforesaid yig tuned oscillator.
The yig tuned oscillator of the described employing of the utility model PCB technology has solved lamped element and in radio frequency path, can cause problems such as impedance sudden change, failure of oscillation, has reached the purpose of widening operating frequency range.
And the described yig tuned oscillator of the utility model also has the following advantages:
1, the element that adopts the PCB Copper Foil to constitute, setting member parameter is arbitrarily produced and is debugged also convenient;
2, between the positive supply input of oscillating circuit and power output end, be connected a big filter capacitor, reduced greatly because the influence that the power supply output ripple produces oscillating circuit;
3, no longer too much receive the restriction in space through the relative position of SMA output interface and feedthrough capacitor suitably being set, making the components and parts of putting oscillating circuit.
Description of drawings
Fig. 1 is the basic principle structure chart of scan-type spectrum analyzer 1.
Fig. 2 is the basic principle structure chart of yig tuned oscillator 2.
Fig. 3 is the structural representation of the yig tuned oscillator 3 described in the embodiment.
Fig. 4 is that the position of SMA output interface 36 and first feedthrough capacitor 34 and second feedthrough capacitor 35 concerns sketch map.
Embodiment
Introduce a preferred embodiments of the utility model below in conjunction with accompanying drawing.
With reference to figure 3; The described yig tuned oscillator 3 of the utility model comprises an external power supply 31, a sealing magnet 32 and an oscillating unit 33, and on the shell of sealing magnet 32, is connected with one first feedthrough capacitor 34, second feedthrough capacitor 35 and a SMA output interface 36.
Oscillating unit 33 is to adopt PCB technology to process, and an emitter feed circuit 331, ground capacity 332, YIG coupling unit 333, microwave transistor 334, collector electrode feed circuit 335, an output circuit 336 are installed on its pcb board.Wherein YIG coupling unit 333 is made up of coupling loop and YIG bead.
External power supply 31 is installed in the outside of sealing magnet 32; The positive-negative output end of external power supply 31 is connected with second feedthrough capacitor 35 with first feedthrough capacitor 34 respectively; External power supply 31 earth terminals are connected with sealing magnet 32; Oscillating unit 33 is installed in the inside of sealing magnet 32; The positive-negative power input of oscillating unit 33 is connected with second feedthrough capacitor 35 with first feedthrough capacitor 34 respectively; The output of oscillating unit 33 is connected with SMA output interface 36, and emitter feed circuit 331 and YIG coupling unit 333 are connected in series between the emitter of negative supply input and microwave transistor 334 of oscillating unit 33 successively, and collector electrode feed circuit 335 is connected in series between the collector electrode of positive supply input and microwave transistor 334 of oscillating unit 33; Output circuit 336 is connected in series between the output of collector electrode and oscillating unit 33 of microwave transistor 334; Between emitter feed circuit 331 and YIG coupling unit 333, be connected with the ground capacity 332 of a ground connection, ground capacity 332 is to be made up of the Copper Foil on the pcb board.
Sealing magnet 32 is enclosed electromagnet structures that adopt magnetic material to be processed into; It comprises a base and a cover plate; The main coil of electromagnet apparatus and the syntonizing coil that fine tune magnetic field is used are installed on the base; Base and cover plate are tightened in together through hex(agonal)screw, form the electromagnet structure of a sealing, are used to the magnetic circuit that oscillating unit 33 provides a sealing.External power supply 31 is tightened on the hex(agonal)screw through Philip's head screw; Realize the fixing of external power supply 31; In order to realize that external power supply 31 is 33 power supplies of internal oscillator unit; On the cover board open and get aperture; Realize the positive-negative power output of external power supply 31 and being electrically connected of sealing magnet 32 through first feedthrough capacitor 34 and second feedthrough capacitor 35, the pin of first feedthrough capacitor 34 and second feedthrough capacitor 35 is imported with the introducing one by one of accomplishing voltage in the sealing jack of elasticity draw-in groove through inserting on the external power supply 31 one to one, and; The positive-negative power input of oscillating unit 33 is connected with second feedthrough capacitor 35 with first feedthrough capacitor 34 respectively, thereby realized being connected of external power supply 31 and oscillating unit 33.The pcb board of oscillating unit 33 is installed on the cover plate of sealing magnet 32; Emitter feed circuit 331 in the oscillating unit 33 is connected to through the coupling loop in the YIG coupling unit 333 on the emitter that is added to microwave transistor 334, and collector electrode feed circuit 335 is added on the collector electrode of microwave transistor 334, and output circuit 336 also is added on the collector electrode of microwave transistor 334; Output circuit 336 comprises broadband matching circuit and buffering amplifier; Broadband matching network can influence the input impedance of microwave transistor 334, makes it in broadband range, be in the negative resistance state, thereby increases the vibration bandwidth; Can also the output impedance of microwave transistor 334 be compensated in frequency band internal reactance value; Make it become very little, be beneficial to the output of its power, buffer amplifier is used to make power output to reach the output requirement; The output of oscillating unit 33 is connected with SMA output interface 36, and the SMA output interface is fixed on the cover plate of sealing magnet 32 through fixed pedestal.
Between emitter feed circuit 331 and YIG coupling unit 333, be connected with ground capacity 332, be used to realize the ground connection of radio frequency path; In the utility model; Ground capacity 332 forms through applying copper corrosion at pcb board, and the size of the area through the debugging copper sheet can change the input impedance of microwave transistor 334 emitters; Make it in operating frequency range, become negative resistance, thereby realize vibration.
As additional embodiments, the span of ground capacity 332 can be between 1pF-5pF, and concrete value can be confirmed according to system requirements and concrete debug results.
As additional embodiments; Can adopt the rectangle copper sheet; Copper segment or interdigitated copper sheet constitute ground capacity 332, can be according to different designing requirement, and the copper sheet that takes different shapes is grounded electric capacity 332; When the operating frequency of oscillator requires to hang down, can consider to be suitable for interdigitated electric capacity.
As additional embodiments, between the positive output end of external power supply 31 and first feedthrough capacitor 34, be connected the filter capacitor 37 of a Da Rong value, the span of its electric capacity is 100pF-400pF.
As additional embodiments, between the positive output end of external power supply 31 and first feedthrough capacitor 34, be connected the filter capacitor 37 of a Da Rong value, the span of its electric capacity is 220pF-330pF.
As additional embodiments, between the positive output end of external power supply 31 and first feedthrough capacitor 34, be connected the filter capacitor 37 of a Da Rong value, the value of its electric capacity is 220pF.
Between external power supply 31 and oscillating unit 33, connect filter capacitor 37, can effectively eliminate the interference that external power supply 31 produces owing to the influence that receives the outside noise signal oscillating unit 33.
As additional embodiments; With reference to figure 4, on the cover plate of sealing magnet 32, the line of the long axis of symmetry of SMA output interface 36 and first feedthrough capacitor 34 and second feedthrough capacitor 35 at an angle; This angle can be arbitrarily angled between the 20-60 degree, and 45 degree are for best.
According to the shortest principle of outgoing route; Nearest with the output of oscillating unit 33 will be satisfied in the installation site of SMA output interface 36 as far as possible; Thereby reduction loss; And the installation site of SMA output interface 36 can not be overlapping with the installation site of first punching 34 and second feedthrough capacitor 35, thus just passable as long as stagger in the position of SMA output interface 36 and first punching 34 and second feedthrough capacitor 35 in principle, but in the practice; The long axis of symmetry of the mounting seat of SMA output interface 36 and first feedthrough capacitor 34 and second feedthrough capacitor 35 to be wired to 20-60 degree angle better, becoming miter angle be the best.
The utility model has also proposed a kind of spectrum measuring device, and it comprises RF signal input end, frequency mixer, amplifier; Filter, wave detector, local oscillator, sweeping generator and display etc.; Its basic principle is the method through the scanning local oscillator, makes the signal of radio-frequency input signals and local oscillator generation carry out mixing, with the intermediate-freuqncy signal that obtains amplify, after the Filtering Processing; Be output as vision signal through wave detector, pass through various computings again, final measurement is exported on display; Wherein said local oscillator adopts aforesaid yig tuned oscillator 3, and concrete implementation method repeats no more with reference to top description here.
The above-described specific embodiment that is merely the utility model; And be not used in qualification protection scope of the present invention; All within spirit of the present invention and principle, any modification of being made, be equal to replacement, improvement etc., all should be included within the protection range of the utility model.
Claims (18)
1. a yig tuned oscillator that adopts PCB technology is characterized in that,
Comprise sealing magnet, oscillating unit, an external power supply and be installed in one first feedthrough capacitor, second feedthrough capacitor and the SMA output interface on the shell of described sealing magnet; Described oscillating unit comprises a pcb board; And be installed in a microwave transistor on the described pcb board, an emitter feed circuit, a ground capacity, a YIG coupling unit, a collector electrode feed circuit, an output circuit
Described external power supply is installed in the outside of described sealing magnet, and its positive-negative output end is connected with second feedthrough capacitor with described first feedthrough capacitor respectively, and its earth terminal is connected with described sealing magnet,
Described oscillating unit is installed in the inside of described sealing magnet; The positive-negative power input of described oscillating unit is connected with second feedthrough capacitor with described first feedthrough capacitor respectively; The output of described oscillating unit is connected with described SMA output interface; Described emitter stage feed circuit and YIG coupling unit are connected in series between the emitter stage of negative supply input and described microwave transistor of described oscillating unit successively; Described colelctor electrode feed circuit is connected in series between the colelctor electrode of positive supply input and described microwave transistor of described oscillating unit; Described output circuit is connected in series between the output of colelctor electrode and described oscillating unit of described microwave transistor
Between described emitter feed circuit and described YIG coupling unit, be connected with the ground capacity of a ground connection, described ground capacity is to be made up of the Copper Foil on the pcb board.
2. tuned oscillator according to claim 1 is characterized in that, the electric capacity span of described ground capacity is 1pF-5pF.
3. tuned oscillator according to claim 2 is characterized in that described ground capacity is made up of the rectangle Copper Foil.
4. tuned oscillator according to claim 2 is characterized in that described ground capacity is made up of fan-shaped Copper Foil.
5. tuned oscillator according to claim 2 is characterized in that described ground capacity is made up of the interdigitated Copper Foil.
6. according to claim 1,2,3,4 or 5 described tuned oscillators, it is characterized in that between the positive output end of described external power supply and described first feedthrough capacitor, be connected with the filter capacitor of a ground connection, its electric capacity span is 100uF-470uF.
7. tuned oscillator according to claim 6 is characterized in that, the electric capacity span of described filter capacitor is 220uF-330uF.
8. tuned oscillator according to claim 7 is characterized in that, the capacitance of described filter capacitor is 220uF.
9. tuned oscillator according to claim 8 is characterized in that, the line of the long axis of symmetry of described SMA output interface and described first feedthrough capacitor and described second feedthrough capacitor at angle, this angle span be 20 the degree-60 the degree.
10. spectrum measuring device; It is characterized in that; Has the described yig tuned oscillator of claim 1; Described yig tuned oscillator comprises sealing magnet, oscillating unit, an external power supply and is installed in one first feedthrough capacitor, second feedthrough capacitor and the SMA output interface on the shell of described sealing magnet
Described oscillating unit comprises a pcb board, and is installed in a microwave transistor on the described pcb board, an emitter feed circuit, a ground capacity, a YIG coupling unit, a collector electrode feed circuit, an output circuit,
Described external power supply is installed in the outside of described sealing magnet, and its positive-negative output end is connected with second feedthrough capacitor with described first feedthrough capacitor respectively, and its earth terminal is connected with described sealing magnet,
Described oscillating unit is installed in the inside of described sealing magnet; The positive-negative power input of described oscillating unit is connected with second feedthrough capacitor with described first feedthrough capacitor respectively; The output of described oscillating unit is connected with described SMA output interface; Described emitter stage feed circuit and YIG coupling unit are connected in series between the emitter stage of negative supply input and described microwave transistor of described oscillating unit successively; Described colelctor electrode feed circuit is connected in series between the colelctor electrode of positive supply input and described microwave transistor of described oscillating unit; Described output circuit is connected in series between the output of colelctor electrode and described oscillating unit of described microwave transistor
Between described emitter feed circuit and described YIG coupling unit, be connected with the ground capacity of a ground connection, described ground capacity is to be made up of the Copper Foil on the pcb board.
11. spectrum measuring device according to claim 10 is characterized in that, the electric capacity span of described ground capacity is 1pF-5pF.
12. spectrum measuring device according to claim 11 is characterized in that, described ground capacity is made up of the rectangle Copper Foil.
13. spectrum measuring device according to claim 11 is characterized in that, described ground capacity is made up of fan-shaped Copper Foil.
14. spectrum measuring device according to claim 11 is characterized in that, described ground capacity is made up of the interdigitated Copper Foil.
15. according to claim 10,11,12,13 or 14 described spectrum measuring devices; It is characterized in that; Between the positive output end of described external power supply and described first feedthrough capacitor, be connected with the filter capacitor of a ground connection, its electric capacity span is 100uF-470uF.
16. spectrum measuring device according to claim 15 is characterized in that, the electric capacity span of described filter capacitor is 220uF-330uF.
17. spectrum measuring device according to claim 16 is characterized in that, the capacitance of described filter capacitor is 220uF.
18. spectrum measuring device according to claim 17 is characterized in that, the line of the long axis of symmetry of described SMA output interface and described first feedthrough capacitor and described second feedthrough capacitor at angle, this angle span be 20 the degree-60 the degree.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011205045034U CN202374217U (en) | 2011-12-07 | 2011-12-07 | Frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting PCB (Printed Circuit Board) technology |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011205045034U CN202374217U (en) | 2011-12-07 | 2011-12-07 | Frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting PCB (Printed Circuit Board) technology |
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| Publication Number | Publication Date |
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| CN202374217U true CN202374217U (en) | 2012-08-08 |
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| CN2011205045034U Expired - Lifetime CN202374217U (en) | 2011-12-07 | 2011-12-07 | Frequency spectrum measuring device and a YIG (Yttrium Iron Garnet) tuned oscillator adopting PCB (Printed Circuit Board) technology |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104779952A (en) * | 2015-04-22 | 2015-07-15 | 西南应用磁学研究所 | Plane integrated yig frequency synthesizer structure |
| CN112800714A (en) * | 2020-12-30 | 2021-05-14 | 科大讯飞股份有限公司 | Printed circuit board design method and related device |
-
2011
- 2011-12-07 CN CN2011205045034U patent/CN202374217U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104779952A (en) * | 2015-04-22 | 2015-07-15 | 西南应用磁学研究所 | Plane integrated yig frequency synthesizer structure |
| CN112800714A (en) * | 2020-12-30 | 2021-05-14 | 科大讯飞股份有限公司 | Printed circuit board design method and related device |
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| GR01 | Patent grant | ||
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| CX01 | Expiry of patent term |
Granted publication date: 20120808 |