CN112953393B - Broadband voltage-controlled oscillator with low phase noise - Google Patents
Broadband voltage-controlled oscillator with low phase noise Download PDFInfo
- Publication number
- CN112953393B CN112953393B CN202110382648.XA CN202110382648A CN112953393B CN 112953393 B CN112953393 B CN 112953393B CN 202110382648 A CN202110382648 A CN 202110382648A CN 112953393 B CN112953393 B CN 112953393B
- Authority
- CN
- China
- Prior art keywords
- resistor
- varactor
- strip line
- transmission line
- grounded
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
- H03B5/08—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance
- H03B5/12—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising lumped inductance and capacitance active element in amplifier being semiconductor device
Landscapes
- Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
Abstract
The invention discloses a broadband voltage-controlled oscillator with low phase noise, which comprises an active amplifying circuit and a frequency selection feedback network; the frequency selective feedback network comprises a loop phase shift network, a filter. The loop phase shift network adopts a structure that a suspended strip line is connected between pairs of two pairs of reverse series varactors which are connected back to provide correct phase shift for the circuit and increase the working bandwidth; the filter is composed of a tuning voltage source, a coupling transmission line and a pair of anti-series varactors connected back to back, wherein the anti-series varactors are also connected to a suspension strip line in the middle, and the coupling transmission line adopts a suspension strip line structure to reduce phase noise. The two ends of the frequency selection feedback network are respectively connected with the base electrode and the collector electrode of the bipolar transistor in the active amplifying circuit. Compared with other voltage-controlled oscillators adopting microstrip structures to design filters, the invention realizes a voltage-controlled oscillator with low phase noise on the basis of broadband.
Description
Technical Field
The invention relates to the field of microwave millimeter wave active devices, in particular to a broadband voltage-controlled oscillator with low phase noise.
Background
In recent years, along with the high-speed development of microwave millimeter wave circuits and systems, the functions of the circuits and the systems are more and more complex, meanwhile, the working frequency of the systems is higher and higher, the working bandwidth is also larger and more demanding on technical indexes of the wireless mobile communication systems, and the voltage-controlled oscillator is a core module in a phase-locked loop. The basic phase-locked loop circuit structure is shown in fig. 3, and consists of the following main modules: phase Detector (PD), loop Filter (LF), voltage Controlled Oscillator (VCO). The phase detector is used to compare the phase of the input signal Fref with the output signal Fout of the voltage controlled oscillator, the output voltage of which is a function of the phase difference corresponding to the two signals. The loop filter is used for filtering out high-frequency components and noise output by the phase discriminator. The voltage-controlled oscillator is controlled by the output voltage of the loop filter, so that the oscillation frequency is close to the frequency of the input signal until the frequencies of the two are the same. Designing a wideband, low phase noise voltage controlled oscillator is related to the performance of the entire pll, which in turn is related to the performance of the entire microwave millimeter wave system.
The voltage-controlled oscillator is a core base device of the microwave millimeter wave circuit and is used for generating a microwave millimeter wave source. Tunable wideband and phase noise are key performance indicators for voltage controlled oscillators. The lower phase noise requires a high quality factor filter to achieve. In practical applications, the advantages of low cost, small size and easy integration of oscillators using planar filters make them increasingly popular in communication systems, such as oscillators with microstrip structures. However, the oscillator of the microstrip structure is difficult to realize low phase noise because its unloaded Q value is very low. As shown in fig. 4, this is a microstrip coupling transmission line electric field profile, where 4, 5, 6 are metal conduction bands, 7 are dielectric plates, 8 are metal floors, and the solid lines with arrows are electric field lines. The microstrip planar circuit is of a semi-open structure, so that radiation loss is large; meanwhile, the dielectric loss of the microstrip line is larger, so that the Q value is lower, which means that the low phase noise of the oscillator with the microstrip structure is difficult to realize. And because the dielectric plate of the microstrip coupling transmission line is thinner, it is difficult to realize closer coupling.
The suspended stripline is also a planar structure, as shown in fig. 5, based on a coupled transmission line electric field profile of the suspended stripline, where 9 is a metal wall, 10, 11, 12 is a metal conduction band, 13 is a dielectric plate, and the solid lines with arrows are electric field lines. Since this is a closed structure, there is no radiation loss; because the dielectric plate is thinner, other parts in the metal cavity are air, and the equivalent dielectric constant is close to 1, the dielectric loss is lower. The structure has the advantages of low transmission loss, high Q value and simple structure, and is suitable for replacing microstrip lines to manufacture filters with low phase noise. Meanwhile, the height adjusting range of the metal cavity is larger, so that the coupling tightness adjusting range is also larger; in addition, in the aspect of processing and manufacturing, the method is compatible with the existing manufacturing of the circuit board, and has the advantage of simplicity and convenience in manufacturing. However, no clear solution has been proposed to further design a voltage controlled oscillator for a filter with a suspended stripline structure, so as to realize a low phase noise wideband voltage controlled oscillator.
Disclosure of Invention
The invention aims to: the invention aims to overcome the defects of the prior art and provide a low-phase noise broadband voltage-controlled oscillator.
The technical scheme is as follows: in order to achieve the purpose, the invention adopts the following technical scheme:
a broadband voltage-controlled oscillator with low phase noise comprises an active amplifying circuit and a frequency selection feedback network; the frequency selection feedback network comprises a loop phase shift network and a filter; the loop phase shift network comprises two pairs of anti-series varactors connected back to back, and a suspension strip line is connected in the middle of the anti-series varactors to provide correct phase shift for the circuit and ensure that the circuit can normally start vibrating within the working bandwidth. The suspended strip line is of a closed structure, low in transmission loss, high in Q value and simple in structure. The filter is fabricated using a coupled transmission line based on a suspended stripline structure, thereby reducing phase noise.
Further, the filter comprises a tuning voltage source, a coupling transmission line and a pair of anti-series varactors connected back to back, wherein the middle of the anti-series varactors is connected with a suspended strip line. The capacitance value of the varactor can be changed by adjusting the tuning voltage source in the frequency selective feedback network, so as to adjust the center frequency of the filter, and realize wideband tuning.
Further, the coupling transmission line is of a suspended strip line structure, and the real object comprises a first metal upper cover, a first circuit board and a first metal lower cover; the first metal upper cover and the first metal lower cover are buckled together to form a cavity, the first circuit board is clamped in the cavity, and the transmission line on the first circuit board, the first metal upper cover and the first metal lower cover form a suspension strip line structure.
Further, the active amplifying circuit comprises a bipolar transistor and a direct current bias network, and provides enough gain for the circuit. And two ends of the frequency selection network are respectively connected with a base electrode and a collector electrode of a bipolar transistor in the active amplifying circuit.
The beneficial effects are that: the invention discloses a broadband voltage-controlled oscillator with low phase noise, which adopts a structure of an indirect suspension strip line in the middle of two pairs of anti-series varactors connected back to back as a loop phase shift network to provide correct phase shift for a circuit and expand working bandwidth; a coupled transmission line based on a suspended stripline structure and a varactor diode are used as a frequency selection unit. Compared with a microstrip filter circuit, the low phase noise is realized on the basis of the broadband of the voltage-controlled oscillator.
Drawings
FIG. 1 is a circuit diagram of a low phase noise wideband voltage controlled oscillator of the present invention
Fig. 2 is an exploded schematic view of a physical model, in which a rectangular block on the first circuit board 2 is a schematic view of circuit elements;
FIG. 3 is a circuit block diagram of a phase locked loop of the background art;
FIG. 4 is an electric field distribution diagram of a microstrip coupled transmission line in the background art;
fig. 5 is a diagram of a coupled transmission line electric field distribution based on a suspended stripline structure in the background art.
Detailed Description
The invention will be further described with reference to the accompanying drawings.
This embodiment discloses a low phase noise wideband voltage controlled oscillator, as shown in fig. 1, comprising an active amplifying circuit and a frequency selective feedback network. The active amplifying circuit comprises a bipolar transistor and a direct current bias circuit; the frequency selection feedback network comprises a loop phase shift network and a filter; the two ends of the frequency selection feedback network are respectively connected with the base electrode and the collector electrode of the bipolar transistor in the active amplifying circuit.
The active amplifying circuit provides enough gain for the system, the Q1 is a bipolar transistor, the direct current bias circuit is arranged according to the bipolar transistor, the active amplifying circuit is ensured to provide enough gain in the whole working frequency bandwidth, the starting condition that the amplitude in the Barkhausen criterion is larger than 1 is met, and the circuit is ensured to work normally; the frequency selective feedback network should provide, in addition to the desired frequency response, the correct phase shift such that the total phase shift of the whole circuit is equal to 0 ° or an integer multiple of 360 °, the barkhausen criterion being fulfilled on the basis of the active amplifying circuit providing sufficient gain: the loop gain is larger than 1, the loop phase shift is equal to 0 degree or integer multiple of 360 degrees, and the normal starting of the circuit is ensured.
The loop phase shift network consists of a suspended strip line and a varactor, SSL1 and SSL2 are suspended strip lines, and compared with a micro-strip line which is a semi-open structure, the suspended strip line is of a closed structure, and has low transmission loss, high Q value and simple structure. VD1, VD2, VD3, VD4 are varactors. While a single varactor can tune the filter over a wider frequency band, the desired phase shift cannot be maintained over a wider range to keep the oscillator running. Thus, the use of multiple diodes in the circuit and the addition of the suspended stripline to collectively adjust the loop phase shift requires optimizing the length of the suspended stripline based on frequency tuning to ensure a very wide tuning range. Meanwhile, as the voltage-capacitance characteristic of the varactor has nonlinearity, nonlinear distortion of the voltage-controlled oscillator can be caused, and the nonlinear distortion of the voltage-controlled oscillator can be reduced by adopting a back-to-back connected anti-series varactor pair mode, a structure that a suspended strip line is inserted into the back-to-back connected anti-series varactor pair is adopted in the circuit, so that correct phase shift is provided for the circuit, the bandwidth is expanded, and the nonlinear distortion is reduced.
The filter is composed of a tuning voltage source, a coupling transmission line and a varactor. Coupled Line1 and Coupled Line2 are Coupled transmission lines based on a suspended strip Line structure, SSL3 is a suspended strip Line, and VD5 and VD6 are varactors. The varactor diode not only provides correct phase shift for the circuit, but also plays a role in adjusting the center frequency of the filter, and under the action of the tuning voltage source Vtune, the varactor diode can change the capacitance value along with the change of voltage to adjust the center frequency of the filter together with the suspended strip line, so that the oscillator can adjust the oscillation frequency under the control of the tuning voltage.
The resistance in the frequency selective feedback network is 22k ohms and is used as a non-resonant rf choke to apply the same tuning voltage to the six varactors and is not affected by the high frequency signal. R1 and R2 in the active amplifying circuit are bias resistors and are used for direct current bias of the bipolar transistor; the capacitors C1 and C2 are used for isolating direct current signals and coupling high-frequency signals.
The Coupled Line1 and the Coupled Line2 connected with the three pairs of varactors are Coupled transmission lines based on a suspended strip Line structure, and since the microstrip planar circuit is a semi-open structure, the transmission loss is large, and the Q value is low, which means that it is difficult to realize a filter with a microstrip structure with low phase noise. The filter is thus implemented using a suspended stripline structure. Firstly, carrying out modeling simulation and tuning optimization on a coupling transmission line model based on a suspended strip line structure in three-dimensional electromagnetic field simulation software, such as High Frequency Structure Simulator (HFSS), determining the width and length of a metal conduction band and the interval between the conduction bands to meet the requirement of frequency selection, and then deriving an S parameter model to be connected with other elements of a circuit in Advanced Design System (ADS) software to carry out collaborative simulation optimization and evaluate the performance.
One end of a power supply VCC in the active amplifying circuit is grounded, the other end of the power supply VCC is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with a collector electrode of the bipolar transistor, one end of a resistor R2 and one end of a capacitor C1. The emitter of the bipolar transistor is grounded, the base of the bipolar transistor is connected with the other end of the resistor R2 and one end of the capacitor C2, the other end of the capacitor C1 is connected with one end of the resistor R3 and the anode of the varactor VD1, and the other end of the resistor R3 is grounded. The cathode of the varactor VD1 is connected with one end of the suspended strip Line SSL1, the other end of the suspended strip Line SSL1 is connected with one end of the resistor R5, the cathode of the varactor VD3, the anode of the varactor VD3 is connected with one end of the resistor R7, the upper right end of the Coupled transmission Line1, the other end of the resistor R7 is grounded, the other end of the capacitor C2 is connected with one end of the resistor R4, the anode of the varactor VD2, and the other end of the resistor R4 is grounded. The cathode of the varactor VD2 is connected with one end of the suspended strip Line SSL2, the other end of the suspended strip Line SSL2 is connected with one end of the resistor R6, the cathode of the varactor VD4, the anode of the varactor VD4 is connected with one end of the resistor R8, the right lower end of the Coupled transmission Line Coupled Line1, and the other end of the resistor R8 is grounded.
The left Bian Sanduan of the Coupled transmission Line Coupled Line1 is respectively connected with the right three ends of the Coupled transmission Line Coupled Line2, one end of a resistor R9 is connected between the left middle end of the Coupled transmission Line Coupled Line1 and the right middle end of the Coupled transmission Line Coupled Line2, the other end of the resistor R9 is grounded, the left middle end of the Coupled transmission Line Coupled Line2 is connected with the anode of a varactor VD6, the cathode of the varactor VD6 is connected with one end of a suspension strip Line SSL3, the other end of the suspension strip Line SSL3 is connected with the cathode of a varactor VD5 and one end of a resistor R10, the anode of the varactor VD5 is grounded, one end of a power supply Vtune is connected with the other end of the resistor R5, the other end of the resistor R6 and the other end of the resistor R10, and the other end of the power supply Vtune is grounded.
The method and the circuit structure provided by the invention can realize a low-phase noise and broadband voltage-controlled oscillator.
Claims (3)
1. A low phase noise wideband voltage controlled oscillator, characterized by: comprises an active amplifying circuit and a frequency selection feedback network; the frequency selection feedback network comprises a loop phase shift network and a filter; the loop phase shift network comprises two pairs of anti-series varactors connected back to back, and a suspension strip line is connected in the middle of the anti-series varactors;
the active amplifying circuit comprises a bipolar transistor and a direct current bias network, and two ends of the frequency selection feedback network are respectively connected with a base electrode and a collector electrode of the bipolar transistor in the active amplifying circuit;
one end of a power supply VCC in the active amplifying circuit is grounded, the other end of the power supply VCC is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with a collector electrode of a bipolar transistor, one end of a resistor R2 and one end of a capacitor C1;
the emitter of the bipolar transistor is grounded, the base of the bipolar transistor is connected with the other end of the resistor R2 and one end of the capacitor C2, the other end of the capacitor C1 is connected with one end of the resistor R3 and the anode of the varactor VD1, and the other end of the resistor R3 is grounded;
the cathode of the varactor VD1 is connected with one end of a suspended strip Line SSL1, the other end of the suspended strip Line SSL1 is connected with one end of a resistor R5 and the cathode of the varactor VD3, the anode of the varactor VD3 is connected with one end of a resistor R7 and the upper right end of a Coupled transmission Line1, the other end of the resistor R7 is grounded, the other end of a capacitor C2 is connected with one end of a resistor R4 and the anode of the varactor VD2, and the other end of the resistor R4 is grounded; the cathode of the varactor VD2 is connected with one end of a suspended strip Line SSL2, the other end of the suspended strip Line SSL2 is connected with one end of a resistor R6 and the cathode of the varactor VD4, the anode of the varactor VD4 is connected with one end of a resistor R8 and the right lower end of a Coupled transmission Line connected Line1, and the other end of the resistor R8 is grounded;
the left Bian Sanduan of the Coupled transmission Line Coupled Line1 is respectively connected with the right three ends of the Coupled transmission Line Coupled Line2, one end of a resistor R9 is connected between the left middle end of the Coupled transmission Line Coupled Line1 and the right middle end of the Coupled transmission Line Coupled Line2, the other end of the resistor R9 is grounded, the left middle end of the Coupled transmission Line Coupled Line2 is connected with the anode of a varactor VD6, the cathode of the varactor VD6 is connected with one end of a suspension strip Line SSL3, the other end of the suspension strip Line SSL3 is connected with the cathode of a varactor VD5 and one end of a resistor R10, the anode of the varactor VD5 is grounded, one end of a power supply Vtune is connected with the other end of the resistor R5, the other end of the resistor R6 and the other end of the resistor R10, and the other end of the power supply Vtune is grounded.
2. A low phase noise wideband voltage controlled oscillator as recited in claim 1 wherein: the filter comprises a tuning voltage source, a coupling transmission line and a pair of anti-series varactor diode pairs which are connected back to back, wherein the middle of each anti-series varactor diode pair is connected with a suspension strip line.
3. A low phase noise wideband voltage controlled oscillator as defined in claim 2 wherein: the coupling transmission line is of a suspended strip line structure, and the real object comprises a first metal upper cover (1), a first circuit board (2) and a first metal lower cover (3); the first metal upper cover and the first metal lower cover are buckled together to form a cavity, the first circuit board (2) is clamped in the middle, and a transmission line on the first circuit board (2), the first metal upper cover (1) and the first metal lower cover (3) form a suspension strip line structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110382648.XA CN112953393B (en) | 2021-04-09 | 2021-04-09 | Broadband voltage-controlled oscillator with low phase noise |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110382648.XA CN112953393B (en) | 2021-04-09 | 2021-04-09 | Broadband voltage-controlled oscillator with low phase noise |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112953393A CN112953393A (en) | 2021-06-11 |
| CN112953393B true CN112953393B (en) | 2023-09-29 |
Family
ID=76231324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110382648.XA Active CN112953393B (en) | 2021-04-09 | 2021-04-09 | Broadband voltage-controlled oscillator with low phase noise |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112953393B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115498962B (en) * | 2022-11-16 | 2023-03-24 | 成都世源频控技术股份有限公司 | Low-phase-noise crystal oscillator circuit and implementation method |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2299422Y (en) * | 1998-01-06 | 1998-12-02 | 大卫·席门 | Broadband electronic oscillator |
| CN1304211A (en) * | 2000-01-11 | 2001-07-18 | 阿尔卑斯电气株式会社 | Oscillator with voltage control |
| CN2586295Y (en) * | 2002-12-12 | 2003-11-12 | 台达电子工业股份有限公司 | Voltage controlled oscillator |
| CN101162889A (en) * | 2006-10-13 | 2008-04-16 | 日本电气株式会社 | Voltage controlled oscillator and its control method |
| CN101453214A (en) * | 2007-08-31 | 2009-06-10 | 广州逸锋电子科技有限公司 | Pasting type voltage controlled oscillator |
| CN101622783A (en) * | 2007-03-06 | 2010-01-06 | 日本电波工业株式会社 | High-frequency voltage-controlled oscillation circuit |
| CN102624334A (en) * | 2012-04-13 | 2012-08-01 | 复旦大学 | Rotary traveling wave voltage controlled oscillator with high power and large tuning ranges |
| JP2013090214A (en) * | 2011-10-19 | 2013-05-13 | Nippon Dempa Kogyo Co Ltd | Voltage-controlled oscillator |
| US8830007B1 (en) * | 2012-03-19 | 2014-09-09 | Scientific Components Corporation | Ultra-low noise VCO |
| CN104617879A (en) * | 2014-11-20 | 2015-05-13 | 成都九洲迪飞科技有限责任公司 | UHF-band wide-band voltage-controlled oscillator |
| CN107508577A (en) * | 2017-09-30 | 2017-12-22 | 天津中科海高微波技术有限公司 | Adjustable Integrated VCO |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2566283C (en) * | 2005-11-02 | 2011-10-18 | Synergy Microwave Corporation | User-definable, low cost, low phase hit and spectrally pure tunable oscillator |
-
2021
- 2021-04-09 CN CN202110382648.XA patent/CN112953393B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2299422Y (en) * | 1998-01-06 | 1998-12-02 | 大卫·席门 | Broadband electronic oscillator |
| CN1304211A (en) * | 2000-01-11 | 2001-07-18 | 阿尔卑斯电气株式会社 | Oscillator with voltage control |
| CN2586295Y (en) * | 2002-12-12 | 2003-11-12 | 台达电子工业股份有限公司 | Voltage controlled oscillator |
| CN101162889A (en) * | 2006-10-13 | 2008-04-16 | 日本电气株式会社 | Voltage controlled oscillator and its control method |
| CN101622783A (en) * | 2007-03-06 | 2010-01-06 | 日本电波工业株式会社 | High-frequency voltage-controlled oscillation circuit |
| CN101453214A (en) * | 2007-08-31 | 2009-06-10 | 广州逸锋电子科技有限公司 | Pasting type voltage controlled oscillator |
| JP2013090214A (en) * | 2011-10-19 | 2013-05-13 | Nippon Dempa Kogyo Co Ltd | Voltage-controlled oscillator |
| US8830007B1 (en) * | 2012-03-19 | 2014-09-09 | Scientific Components Corporation | Ultra-low noise VCO |
| CN102624334A (en) * | 2012-04-13 | 2012-08-01 | 复旦大学 | Rotary traveling wave voltage controlled oscillator with high power and large tuning ranges |
| CN104617879A (en) * | 2014-11-20 | 2015-05-13 | 成都九洲迪飞科技有限责任公司 | UHF-band wide-band voltage-controlled oscillator |
| CN107508577A (en) * | 2017-09-30 | 2017-12-22 | 天津中科海高微波技术有限公司 | Adjustable Integrated VCO |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112953393A (en) | 2021-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Sánchez-Renedo et al. | Tunable combline filter with continuous control of center frequency and bandwidth | |
| CA2608203C (en) | Tunable oscillator having series and parallel tuned resonant circuits | |
| US6326854B1 (en) | Coaxial resonator and oscillation circuits featuring coaxial resonators | |
| CN102970031B (en) | Phase-locked loop frequency synthesizer | |
| KR19980702555A (en) | High-Power, Low-Noise, Voltage-Controlled Oscillator | |
| CN112953393B (en) | Broadband voltage-controlled oscillator with low phase noise | |
| US5748051A (en) | Low phase noise UHF and microwave oscillator | |
| WO2004062084A1 (en) | System and method for an ultra low noise micro-wave coaxial resonator oscillator using 5/8ths wavelength resonator | |
| CN115051650B (en) | S-band frequency-doubling low-phase-noise voltage-controlled oscillator and signal generating device | |
| Nick et al. | A very low phase-noise voltage-controlled-oscillator at X-band | |
| CN107221733A (en) | A kind of HBAR resonators and tunable microwave oscillator | |
| Cai et al. | A low phase noise differential oscillator employing stub-loaded nested split-ring resonator inspired balanced bandpass filter | |
| Poddar et al. | Slow wave resonator based tunable oscillators | |
| Huang et al. | An electrically tunable X-band voltage-controlled oscillator using substrate integrated waveguide dual-mode bandpass filter with circular cavity | |
| Cai et al. | A low phase noise oscillator using SIW combline resonator | |
| US6690244B2 (en) | Low phase-noise integrated voltage controlled oscillator | |
| CN109921807A (en) | A kind of broadband chaotic oscillating circuit | |
| CN217508714U (en) | Voltage-controlled oscillator and signal generating device of frequency doubling band low phase noise | |
| Khamin-Hamedani et al. | Design of low phase-noise oscillators based on microstrip triple-band bandpass filter using coupled lines resonator | |
| Liu et al. | Design of low phase-noise voltage-controlled oscillator using tunable evanescent-mode cavity | |
| Wünsche et al. | Microstrip Combline Bandpass Filter with Tuning Range Enhancement and Bandwidth Tunability Using Resonator Loaded Series Varactor and SLR | |
| Shi et al. | Design of Wideband Voltage Controlled Oscillator with Suspended Stripline Structure | |
| CN210297640U (en) | C-band voltage-controlled oscillator | |
| Rohde et al. | Configurable ultra low noise ultra wideband power efficient VCOs | |
| CN111416576B (en) | Oscillator based on coaxial medium resonant cavity and design method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |