CN116961588B - Low-noise frequency multiplication crystal oscillator circuit - Google Patents
Low-noise frequency multiplication crystal oscillator circuit Download PDFInfo
- Publication number
- CN116961588B CN116961588B CN202311212338.9A CN202311212338A CN116961588B CN 116961588 B CN116961588 B CN 116961588B CN 202311212338 A CN202311212338 A CN 202311212338A CN 116961588 B CN116961588 B CN 116961588B
- Authority
- CN
- China
- Prior art keywords
- capacitor
- transistor
- resistor
- network
- crystal resonator
- 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
- 239000013078 crystal Substances 0.000 title claims abstract description 84
- 230000010355 oscillation Effects 0.000 claims abstract description 32
- 239000003990 capacitor Substances 0.000 claims description 98
- 238000001228 spectrum Methods 0.000 abstract description 3
- 230000005284 excitation Effects 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 7
- 239000010453 quartz Substances 0.000 description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 235000012431 wafers Nutrition 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
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
- H03B19/00—Generation of oscillations by non-regenerative frequency multiplication or division of a signal from a separate source
- H03B19/06—Generation of oscillations by non-regenerative frequency multiplication or division of a signal from a separate source by means of discharge device or semiconductor device with more than two electrodes
- H03B19/14—Generation of oscillations by non-regenerative frequency multiplication or division of a signal from a separate source by means of discharge device or semiconductor device with more than two electrodes by means of a semiconductor device
-
- 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
- H03B1/00—Details
- H03B1/04—Reducing undesired oscillations, e.g. harmonics
-
- 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
- H03B5/30—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator
- H03B5/32—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator being a piezoelectric resonator
- H03B5/36—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element being electromechanical resonator being a piezoelectric resonator active element in amplifier being semiconductor device
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Oscillators With Electromechanical Resonators (AREA)
Abstract
The invention discloses a low-noise frequency multiplication crystal oscillator circuit, which comprises two identical transistor tuning amplifying circuits, two identical crystal resonator networks, a voltage-controlled tuning network and an output matching filter network, wherein the voltage-controlled tuning network is connected with the output matching filter network; the two crystal resonator networks are connected to two ends of the voltage-controlled tuning network, the two transistor tuning amplifying circuits are correspondingly connected to one end of one crystal resonator network, the output matching filter network is symmetrically connected with the output ends of the two transistor tuning amplifying circuits, and two oscillation signals with opposite phases are synthesized into one output. The invention utilizes symmetrical transistor circuits to provide oscillation excitation, simultaneously realizes the circuit functions of oscillation and frequency multiplication, combines fundamental wave signals with opposite phases obtained at two symmetrical points, and obtains high-purity frequency doubling signal output for canceling odd frequency spectrums. The frequency doubling signal obtained by the circuit scheme has better phase noise performance, and the circuit is simple and reliable and is easy to popularize.
Description
Technical Field
The invention belongs to the technical field of quartz crystal oscillators, and particularly relates to a low-noise frequency multiplication crystal oscillator circuit.
Background
As known, quartz crystals exist in a large amount in nature and are easy to synthesize artificially, the acquisition cost is low, and an oscillator made of piezoelectric quartz crystals can generate stable high-quality reference frequency signals, so that the oscillator is always the heart of electronic information equipment such as modern electronic communication equipment, instruments and meters and the like. The oscillation frequency of the crystal oscillator is determined by the natural resonant frequency of the crystal resonator used, and depends on the overall size, the elastic coefficient and the density of the crystal resonator. Quartz wafers have a wide range of vibration modes, in which thickness shear vibration has the characteristics of wide frequency range, good temperature characteristics, high stability, and convenience in processing, and therefore, the application is the greatest. The quartz crystal resonant frequency based on thickness shearing work is inversely proportional to the thickness, the higher the resonant frequency is, the thinner the wafer is, and the greater the processing difficulty is, so that the output frequency of the crystal oscillator cannot be too high, and is generally not more than 200MHz.
In engineering practice, the output signal of a crystal oscillator is often multiplied by a frequency multiplication chain of special frequency multiplication-filtering-amplification to obtain the required high frequency reference signal. In the prior art, a special frequency multiplication circuit is generally adopted to realize the multiplication of the crystal oscillator output frequency, a plurality of harmonic frequency multiplication technologies based on PN junction nonlinearity are developed, such as a Schottky diode frequency multiplication technology (US 5434522), a varactor diode-based nonlinear transmission line (NLTL) technology, a step-by-Step Recovery Diode (SRD) frequency multiplication technology, a transistor active frequency multiplication technology (US 6549083 B2) and the like, a frequency tripling scheme which is realized by using a transistor PN junction nonlinearity is adopted by a patent CN 201830202U, and a frequency doubling device based on a crystal oscillator circuit is also disclosed by the patent CN104767488A, wherein the scheme can obtain-140 dBc/Hz@1kHz phase noise when the frequency doubling output frequency is 120 MHz; there are also companies that sell specialized frequency multipliers such as the AMK series frequency multiplier products provided by Mini-circles. According to the prior frequency doubling technical scheme, the additional frequency doubling phase noise is deteriorated according to the 20log N rule, and when the frequency doubling is performed (N=2), the additional phase noise is deteriorated by at least 6dB, and the special frequency doubling circuit realizes the multiplication of the crystal oscillator output frequency, so that the frequency doubling circuit is inconvenient to use, complex in circuit, large in size and high in power consumption.
Disclosure of Invention
The invention aims to provide a low-noise frequency multiplication crystal oscillator circuit, which mainly solves the problems of inconvenient use, complex circuit, large volume and high power consumption of the traditional frequency multiplication crystal oscillator.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a low-noise frequency multiplication crystal oscillator circuit comprises two identical transistor tuning amplifying circuits, two identical crystal resonator networks, a voltage-controlled tuning network and an output matching filter network; the output matching filter network is symmetrically connected with the output ends of the two transistor tuning amplifying circuits, and two oscillation signals with opposite phases are synthesized into one path for output; the transistor tuning amplifying circuits are connected with each other.
Further, in the present invention, the two transistor tuning amplifying circuits are respectively denoted as a first amplifying circuit and a second amplifying circuit;
the first amplifying circuit comprises a transistor Q1, a voltage dividing resistor R1 and a voltage dividing resistor R2, wherein one end of the voltage dividing resistor R3 is connected with a collector of the transistor Q1, the other end of the voltage dividing resistor R2 is connected with a power supply VCC, one end of the voltage dividing resistor R1 is connected with the power supply VCC after being connected in series, one end of the resistor R3 is connected with a base of the transistor Q1, the other end of the resistor R3 is connected with a common end of the voltage dividing resistor R1 and the voltage dividing resistor R2, a capacitor C3 is connected between the base and an emitter of the transistor Q1, a capacitor C4 is connected between the emitter of the transistor Q1 and the ground, a resistor R4 is connected with the emitter of the transistor Q1 at one end, and inductors L4 and C5 are connected with the other end of the resistor R4 after being connected in parallel; wherein the oscillation signal is taken out from the collector a point of the transistor Q1;
the second amplifying circuit comprises a transistor Q2, a voltage dividing resistor R10 and a voltage dividing resistor R11, wherein one end of the voltage dividing resistor R10 is connected with the collector of the transistor Q1, the other end of the voltage dividing resistor R11 is connected with the power supply VCC, a resistor R9, the other end of the resistor R9 is connected with the base of the transistor Q1, the other end of the resistor R9 is connected with the common end of the voltage dividing resistor R10 and the voltage dividing resistor R11, a capacitor C12 is connected between the base and the emitter of the transistor Q1, a capacitor C13 is connected between the emitter of the transistor Q1 and the ground, a resistor R8, one end of which is connected with the emitter of the transistor Q2, and inductors L7 and C11, the other end of which are connected with the other end of the resistor R8 in parallel, are connected with each other;
wherein another oscillating signal with the opposite phase to the signal at the point a is taken out from the point B of the collector of the transistor Q2.
Further, in the present invention, two of the crystal resonator networks are denoted as a first crystal network and a second crystal network, respectively;
the first crystal network comprises a crystal resonator Y1 and an inductor L1 connected in parallel with the crystal resonator Y1, an inductor L2 with one end connected with the base electrode of the transistor Q1 and the other end connected with the crystal resonator Y1, and a capacitor C1 with one end connected with the crystal resonator Y1 and the other end connected with the voltage-controlled tuning network;
the second crystal network comprises a crystal resonator Y2 and an inductor L9 connected in parallel with the crystal resonator Y2, an inductor L8 with one end connected with the base of the transistor Q2 and the other end connected with the crystal resonator Y2, and a capacitor C15 with one end connected with the crystal resonator Y2 and the other end connected with the voltage-controlled tuning network.
Further, in the present invention, the voltage-controlled tuning network includes a varactor diode D1, a resistor R5 with one end connected to the positive electrode of the varactor diode D1 and the other end connected to ground, a resistor R6 with one end connected to the negative electrode of the varactor diode D1 and the other end connected in series in turn and connected to an external voltage-controlled terminal EFC, a resistor R7, and a capacitor C7 with one end connected between the resistor R6 and the resistor R7 and the other end grounded; the positive electrode of the varactor diode D1 is also connected with one end of the capacitor C1; the negative pole of the varactor diode D1 is also connected to one end of the capacitor C15.
Further, in the invention, the output matching filter network consists of a capacitor C6, a capacitor C8, a capacitor C9, a capacitor C10 and an inductor L5; the capacitor C6 and the capacitor C10 are connected in series and then are respectively connected to the collector A, B points of the transistor Q1 and the transistor Q2, one end of the capacitor C9 is connected to the ground, the other end of the capacitor C9 is connected to the common end of the capacitor C6 and the capacitor C7, one end of the inductor L5 is connected to the common node of the capacitor C6, the capacitor C9 and the capacitor C10, the other end of the inductor L5 is connected to the capacitor C8, and the radio frequency signal RF is output from the other end of the capacitor C8.
Further, in the invention, the power supply filter capacitor C2 and the power supply filter capacitor C14 are also included; the power supply filter capacitor C2 and the power supply filter capacitor C14 are respectively connected between the power supply VCC and the ground.
Compared with the prior art, the invention has the following beneficial effects:
(1) The transistor tuning amplifying circuit adopts two completely symmetrical amplifiers to form a differential structure, two paths of differential signals with opposite phases are led out from the same positions of the collector electrodes of the two oscillating transistors, the fundamental wave signals and odd harmonic signals of the oscillators can be effectively counteracted after the two paths of differential signals are combined, and the high-purity even frequency doubling signals are obtained.
(2) The output signal of the invention is directly synthesized by two opposite phase oscillation signals, the degradation of theoretical phase noise is only 3dB during frequency doubling, and the phase noise theory of a conventional frequency doubling circuit is modified to 6dB. Therefore, the scheme of the invention can obtain the frequency multiplication signal with better phase noise than the prior frequency multiplication circuit.
Drawings
Fig. 1 is a schematic diagram of a frequency multiplied oscillator circuit of the present invention.
Fig. 2 is a differential signal output by the oscillating circuit of the present invention.
Fig. 3 is a frequency spectrum of the output frequency multiplication signal of the main oscillating circuit of the present invention.
Fig. 4 is a graph of phase noise of a 100MHz ultra low phase noise oscillator fundamental signal, a conventional frequency doubling signal, and a frequency doubling signal synthesized by differential oscillation using the present invention.
Detailed Description
The invention will be further illustrated by the following description and examples, which include but are not limited to the following examples.
As shown in fig. 1, the low-noise frequency multiplication crystal oscillator circuit disclosed by the invention utilizes the characteristic that odd harmonics can be counteracted after a differential radio frequency signal is combined, adopts a differential structure to form a main oscillation circuit, outputs differential oscillation signals at two symmetrical points of the main oscillation circuit, directly synthesizes and outputs even frequency multiplication signals, and has simple circuit and easy integration. Different from the synthesis after power division, the scheme synthesizes two paths of oscillation signals, the phase noise of the signal after frequency multiplication is obviously optimized compared with the traditional frequency multiplication technology, and the frequency multiplication signal with high frequency spectrum purity and better phase noise index can be output.
The frequency doubling crystal oscillator circuit comprises two completely symmetrical transistor tuning amplifying circuits, crystal resonator networks respectively led out from the base electrodes of the transistors, voltage-controlled tuning networks connecting the two crystal resonator networks together, and output matching networks respectively connected with the collector electrodes of the transistors and outputting frequency doubling signals; the transistor tuning amplifying circuit consists of a radio frequency transistor, a direct current bias circuit and an LC tuning network; the crystal resonator network consists of a quartz crystal resonator, a neutralization inductor, a frequency modulation inductor and a capacitor; the voltage-controlled tuning network consists of a varactor and a direct current biasing element thereof; the output matching filter network consists of an LC frequency-selecting network.
In this embodiment, the two transistor tuning amplifying circuits are respectively denoted as a first amplifying circuit and a second amplifying circuit; the first amplifying circuit comprises a transistor Q1, a voltage dividing resistor R1 and a voltage dividing resistor R2, wherein one end of the voltage dividing resistor R3 is connected with a collector of the transistor Q1, the other end of the voltage dividing resistor R2 is connected with a power supply VCC, one end of the voltage dividing resistor R1 is connected with the power supply VCC after being connected in series, one end of the resistor R3 is connected with a base of the transistor Q1, the other end of the resistor R3 is connected with a common end of the voltage dividing resistor R1 and the voltage dividing resistor R2, a capacitor C3 is connected between the base and an emitter of the transistor Q1, a capacitor C4 is connected between the emitter of the transistor Q1 and the ground, a resistor R4 is connected with the emitter of the transistor Q1 at one end, and inductors L4 and C5 are connected with the other end of the resistor R4 after being connected in parallel; wherein the oscillating signal is taken out from the collector a point of the transistor Q1.
The second amplifying circuit comprises a transistor Q2, a voltage dividing resistor R10 and a voltage dividing resistor R11, wherein one end of the voltage dividing resistor R10 is connected with the collector of the transistor Q1, the other end of the voltage dividing resistor R11 is connected with the power supply VCC, a resistor R9, the other end of the resistor R9 is connected with the base of the transistor Q1, the other end of the resistor R9 is connected with the common end of the voltage dividing resistor R10 and the voltage dividing resistor R11, a capacitor C12 is connected between the base and the emitter of the transistor Q1, a capacitor C13 is connected between the emitter of the transistor Q1 and the ground, a resistor R8, one end of which is connected with the emitter of the transistor Q2, and inductors L7 and C11, the other end of which are connected with the other end of the resistor R8 in parallel, are connected with each other;
wherein another oscillating signal with the opposite phase to the signal at the point a is taken out from the point B of the collector of the transistor Q2.
In this embodiment, the two crystal resonator networks are denoted as a first crystal network and a second crystal network, respectively; the first crystal network comprises a crystal resonator Y1 and an inductor L1 connected in parallel with the crystal resonator Y1, an inductor L2 with one end connected with the base electrode of the transistor Q1 and the other end connected with the crystal resonator Y1, and a capacitor C1 with one end connected with the crystal resonator Y1 and the other end connected with the voltage-controlled tuning network.
The second crystal network comprises a crystal resonator Y2 and an inductor L9 connected in parallel with the crystal resonator Y2, an inductor L8 with one end connected with the base of the transistor Q2 and the other end connected with the crystal resonator Y2, and a capacitor C15 with one end connected with the crystal resonator Y2 and the other end connected with the voltage-controlled tuning network.
In this embodiment, the voltage-controlled tuning network includes a varactor diode D1, a resistor R5 with one end connected to the positive electrode of the varactor diode D1 and the other end connected to ground, a resistor R6 with one end connected to the negative electrode of the varactor diode D1 and the other end connected in series in turn and connected to an external voltage-controlled terminal EFC, a resistor R7, and a capacitor C7 with one end connected between the resistor R6 and the resistor R7 and the other end grounded; the positive electrode of the varactor diode D1 is also connected with one end of the capacitor C1; the negative pole of the varactor diode D1 is also connected to one end of the capacitor C15.
In this embodiment, the output matching filter network is composed of a capacitor C6, a capacitor C8, a capacitor C9, a capacitor C10 and an inductor L5; the capacitor C6 and the capacitor C10 are connected in series and then are respectively connected to the collector A, B points of the transistor Q1 and the transistor Q2, one end of the capacitor C9 is connected to the ground, the other end of the capacitor C9 is connected to the common end of the capacitor C6 and the capacitor C7, one end of the inductor L5 is connected to the common node of the capacitor C6, the capacitor C9 and the capacitor C10, the other end of the inductor L5 is connected to the capacitor C8, and the radio frequency signal RF is output from the other end of the capacitor C8.
In this embodiment, the oscillator circuit further includes a power supply filter capacitor C2 and a power supply filter capacitor C14; the power supply filter capacitor C2 and the power supply filter capacitor C14 are respectively connected between the power supply VCC and the ground.
In fig. 1, the radio frequency transistors Q1 and Q2 are main vibration excitation transistors, during operation, the voltage division capacitors C3 and C4 and the first crystal network meet the capacitor three-point oscillation condition, the voltage division capacitors C12 and C13 and the second crystal network meet the capacitor three-point oscillation condition, the values of the voltage division capacitors C3 and C4 and the voltage division capacitors C12 and C13 are properly adjusted, the circuit meets the phase condition and the gain condition necessary for oscillation, the circuit oscillates around the resonance frequency of the crystal resonator, and the circuit starts to oscillate, and the oscillation signal is a fundamental wave signal.
The LC parallel resonance networks respectively composed of the inductor L4, the capacitor C5, the inductor L7 and the capacitor C11 are all resonant near the fundamental frequency of the oscillator and are in a high-resistance state for the oscillating signal, so that the gain of an amplifying circuit can be increased, the signal-to-noise ratio of a loop can be improved, and the phase noise of the oscillating signal can be improved.
The inductor L2 and the inductor L8 are connected in series in respective crystal resonance networks to play a role in adjusting the oscillation frequency, the oscillation frequency can be reduced by increasing the inductance value of the inductor L2 and the inductor L8, and the oscillation frequency can be increased by reducing the inductance value of the inductor L; the capacitors C1 and C15 are also connected in series in the respective crystal resonance networks, and have the functions of blocking direct current signals and adjusting the oscillation frequency, increasing the capacitance value of the capacitors can reduce the oscillation frequency, and reducing the capacitance value of the capacitors can increase the oscillation frequency; the inductors L1 and L9 are respectively connected in parallel at two ends of the crystal resonators Y1 and Y2, and are connected in parallel with the electrostatic capacitances of the two crystal resonators to resonate at the oscillation frequency so as to neutralize the electrostatic capacitances of the crystal resonators.
In the voltage-controlled tuning network, a varactor diode D1 is connected in series between two crystal resonator networks, and a resistor R5 is connected between the anode of the varactor diode D1 and the ground to provide zero-level reference voltage for the varactor diode D1; the resistors R6 and R7 are connected to the voltage-controlled voltage end EFC and the negative electrode of the varactor diode D1, and the direct-current voltage-controlled tuning voltage given by the voltage-controlled end EFC is loaded to the varactor diode through the resistors R6 and R7. When the EFC voltage is increased, the capacitance of the varactor diode junction is reduced, the fundamental frequency is increased, and when the EFC voltage is reduced, the capacitance of the varactor diode junction is increased, and the fundamental frequency is reduced; the capacitor C7 is connected between nodes R6 and R7 of the resistor and the ground, and R7 forms a typical RC low-pass filter, so that high-frequency noise signals which are connected in series by the voltage-controlled end EFC can be filtered, and phase noise of the oscillation signals during voltage-controlled tuning can be improved.
The output matching filter network is a four-port network, one end of the output matching filter network is grounded through a capacitor C9, two symmetrical ports are respectively connected to a collector A of a transistor Q1 and a collector B of a transistor Q2 through capacitors C6 and C10 with the same capacitance value, and a combined signal is sequentially output through an inductor L5 and a capacitor C8 to obtain a final radio frequency signal RF; in addition, the dc feed inductances L3, L6 on the one hand supply the transistors Q1, Q2 with dc voltages, respectively, and on the other hand participate in tuning together with the output matching network in order to output a frequency-doubled signal satisfying the requirements.
In particular, the two transistor tuning amplifying circuits and the resonator network circuit are symmetrical, and the values of the corresponding circuit elements are completely the same, so that differential signals with opposite phases are obtained at the collector A of the transistor Q1 and the collector B of the transistor Q2, as shown in figure 2, and the inhibition of the frequency doubling signals after the combination on odd harmonic signals of fundamental wave frequency is achieved; tuning output matching network element values, and conveniently obtaining even frequency multiplication signals such as frequency doubling and frequency quadrupling of oscillation fundamental wave signals at a radio frequency output end RF; as shown in fig. 3.
In the circuit scheme of the invention, the main oscillation circuit directly generates two paths of differential oscillation signals with opposite phases, and after the two paths of differential oscillation signals are combined, even-order frequency multiplication signals for canceling odd harmonics of an oscillation fundamental wave signal are directly output, so that the circuit is simple and easy to integrate. In addition, the main vibration circuit directly generates two paths of differential signals with the same frequency and opposite phases, and the frequency multiplication signal obtained after power synthesis has better phase noise index than the traditional frequency multiplication signal. FIG. 4 is a graph showing the comparison of phase noise of a 100MHz low noise oscillator, 200MHz phase noise of 100MHz double output, and 200MHz signal phase noise index obtained by differential oscillation of the present invention. It can be seen that the differential frequency doubling circuit scheme of the invention has very obvious improvement on the phase noise performance compared with the traditional frequency doubling circuit technology. In addition, through the circuit scheme of the invention, a crystal resonator with lower fundamental wave frequency can be adopted to realize high-frequency output, the circuit is simple and easy to integrate, and the circuit has obvious advantages in the aspects of frequency stability, cost control and the like.
The above embodiment is only one of the preferred embodiments of the present invention, and should not be used to limit the scope of the present invention, but all the insubstantial modifications or color changes made in the main design concept and spirit of the present invention are still consistent with the present invention, and all the technical problems to be solved are included in the scope of the present invention.
Claims (4)
1. The low-noise frequency multiplication crystal oscillator circuit is characterized by comprising two identical transistor tuning amplifying circuits, two identical crystal resonator networks, a voltage-controlled tuning network and an output matching filter network; the output matching filter network is symmetrically connected with the output ends of the two transistor tuning amplifying circuits, and two oscillation signals with opposite phases are synthesized into one path for output; the transistor tuning amplifying circuits are connected with each other;
the voltage-controlled tuning network comprises a varactor diode D1, a resistor R5, a resistor R6 and a resistor R7, wherein one end of the resistor R5 is connected with the positive electrode of the varactor diode D1, the other end of the resistor R5 is connected with the ground, one end of the resistor R6 is connected with the negative electrode of the varactor diode D1, the other end of the resistor R6 is connected with an external voltage-controlled end EFC in series, and one end of the capacitor C7 is connected between the resistor R6 and the resistor R7; the positive electrode and the negative electrode of the varactor diode D1 are also connected with a crystal resonator network;
the output matching filter network consists of a capacitor C6, a capacitor C8, a capacitor C9, a capacitor C10 and an inductor L5; the capacitor C6 and the capacitor C10 are connected in series and then connected to the two transistor tuning amplifying circuits respectively, one end of the capacitor C9 is connected to the ground, the other end of the capacitor C9 is connected to the common end of the capacitor C6 and the common end of the capacitor C10, one end of the inductor L5 is connected to the common node of the capacitor C6, the capacitor C9 and the capacitor C10, the other end of the inductor L5 is connected to the capacitor C8, and the radio frequency signal RF is output from the other end of the capacitor C8.
2. The low noise frequency doubling crystal oscillator circuit according to claim 1, wherein two of the transistor tuning amplifying circuits are respectively denoted as a first amplifying circuit and a second amplifying circuit;
the first amplifying circuit comprises a transistor Q1, a voltage dividing resistor R1 and a voltage dividing resistor R2, wherein one end of the voltage dividing resistor R3 is connected with a collector of the transistor Q1, the other end of the voltage dividing resistor R2 is connected with a power supply VCC, one end of the voltage dividing resistor R1 is connected with the power supply VCC after being connected in series, one end of the resistor R3 is connected with a base of the transistor Q1, the other end of the resistor R3 is connected with a common end of the voltage dividing resistor R1 and the voltage dividing resistor R2, a capacitor C3 is connected between the base and an emitter of the transistor Q1, a capacitor C4 is connected between the emitter of the transistor Q1 and the ground, a resistor R4 is connected with the emitter of the transistor Q1 at one end, and inductors L4 and C5 are connected with the other end of the resistor R4 after being connected in parallel; wherein the oscillation signal is taken out from the collector a point of the transistor Q1;
the second amplifying circuit comprises a transistor Q2, a voltage dividing resistor R10 and a voltage dividing resistor R11, wherein one end of the voltage dividing resistor R10 is connected with the collector of the transistor Q1, the other end of the voltage dividing resistor R11 is connected with the power supply VCC, a resistor R9, the other end of the resistor R9 is connected with the base of the transistor Q1, the other end of the resistor R9 is connected with the common end of the voltage dividing resistor R10 and the voltage dividing resistor R11, a capacitor C12 is connected between the base and the emitter of the transistor Q1, a capacitor C13 is connected between the emitter of the transistor Q1 and the ground, a resistor R8, one end of which is connected with the emitter of the transistor Q2, and inductors L7 and C11, the other end of which are connected with the other end of the resistor R8 in parallel, are connected with each other;
wherein another oscillating signal with the opposite phase to the signal at the point a is taken out from the point B of the collector of the transistor Q2.
3. The low noise frequency doubling crystal oscillator circuit according to claim 2, wherein two of the crystal resonator networks are denoted as a first crystal network and a second crystal network, respectively;
the first crystal network comprises a crystal resonator Y1 and an inductor L1 connected in parallel with the crystal resonator Y1, an inductor L2 with one end connected with the base electrode of the transistor Q1 and the other end connected with the crystal resonator Y1, and a capacitor C1 with one end connected with the crystal resonator Y1 and the other end connected with the voltage-controlled tuning network;
the second crystal network comprises a crystal resonator Y2 and an inductor L9 connected in parallel with the crystal resonator Y2, an inductor L8 with one end connected with the base of the transistor Q2 and the other end connected with the crystal resonator Y2, and a capacitor C15 with one end connected with the crystal resonator Y2 and the other end connected with the voltage-controlled tuning network.
4. The low noise frequency doubling crystal oscillator circuit according to claim 3, further comprising a power supply filter capacitor C2 and a power supply filter capacitor C14; the power supply filter capacitor C2 and the power supply filter capacitor C14 are respectively connected between the power supply VCC and the ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311212338.9A CN116961588B (en) | 2023-09-20 | 2023-09-20 | Low-noise frequency multiplication crystal oscillator circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311212338.9A CN116961588B (en) | 2023-09-20 | 2023-09-20 | Low-noise frequency multiplication crystal oscillator circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116961588A CN116961588A (en) | 2023-10-27 |
| CN116961588B true CN116961588B (en) | 2023-12-29 |
Family
ID=88446505
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311212338.9A Active CN116961588B (en) | 2023-09-20 | 2023-09-20 | Low-noise frequency multiplication crystal oscillator circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116961588B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004297840A (en) * | 2004-07-22 | 2004-10-21 | Nippon Telegr & Teleph Corp <Ntt> | Voltage-controlled oscillator |
| JP2004320414A (en) * | 2003-04-16 | 2004-11-11 | Toyo Commun Equip Co Ltd | Spurious suppression high frequency oscillation circuit |
| JP2005101964A (en) * | 2003-09-25 | 2005-04-14 | Toyo Commun Equip Co Ltd | High frequency multiple oscillation circuit |
| JP2012049961A (en) * | 2010-08-30 | 2012-03-08 | Nec Corp | Push-push oscillator and phase shift monitoring method |
| CN202713231U (en) * | 2012-07-04 | 2013-01-30 | 上海鸿晔电子科技有限公司 | high frequency low phase noise constant temperature crystal oscillation circuit |
| JP2015008397A (en) * | 2013-06-25 | 2015-01-15 | 日本電気株式会社 | Voltage-controlled oscillator and method of controlling the same |
| CN104348416A (en) * | 2013-07-29 | 2015-02-11 | 日本电波工业株式会社 | Differential oscillator |
| CN106374836A (en) * | 2016-10-14 | 2017-02-01 | 北京无线电计量测试研究所 | Voltage-controlled temperature-compensated crystal oscillator |
| CN109239568A (en) * | 2018-10-19 | 2019-01-18 | 北京无线电计量测试研究所 | A kind of test circuit and test device for quartz resonator |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9240755B2 (en) * | 2013-04-17 | 2016-01-19 | Nihon Dempa Kogyo Co., Ltd. | Oscillator circuit |
-
2023
- 2023-09-20 CN CN202311212338.9A patent/CN116961588B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004320414A (en) * | 2003-04-16 | 2004-11-11 | Toyo Commun Equip Co Ltd | Spurious suppression high frequency oscillation circuit |
| JP2005101964A (en) * | 2003-09-25 | 2005-04-14 | Toyo Commun Equip Co Ltd | High frequency multiple oscillation circuit |
| JP2004297840A (en) * | 2004-07-22 | 2004-10-21 | Nippon Telegr & Teleph Corp <Ntt> | Voltage-controlled oscillator |
| JP2012049961A (en) * | 2010-08-30 | 2012-03-08 | Nec Corp | Push-push oscillator and phase shift monitoring method |
| CN202713231U (en) * | 2012-07-04 | 2013-01-30 | 上海鸿晔电子科技有限公司 | high frequency low phase noise constant temperature crystal oscillation circuit |
| JP2015008397A (en) * | 2013-06-25 | 2015-01-15 | 日本電気株式会社 | Voltage-controlled oscillator and method of controlling the same |
| CN104348416A (en) * | 2013-07-29 | 2015-02-11 | 日本电波工业株式会社 | Differential oscillator |
| CN106374836A (en) * | 2016-10-14 | 2017-02-01 | 北京无线电计量测试研究所 | Voltage-controlled temperature-compensated crystal oscillator |
| CN109239568A (en) * | 2018-10-19 | 2019-01-18 | 北京无线电计量测试研究所 | A kind of test circuit and test device for quartz resonator |
Non-Patent Citations (1)
| Title |
|---|
| 一种低相噪压控振荡器的设计与实现;张振宇;索瑞隆;杨爱军;赵凡;;无线电工程(第02期);78-81 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116961588A (en) | 2023-10-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106877819B (en) | Voltage controlled oscillator based on composite resonator | |
| US6094103A (en) | Multiple feedback loop ring oscillator and delay cell | |
| US7545229B2 (en) | Tunable frequency, low phase noise and low thermal drift oscillator | |
| US7902930B2 (en) | Colpitts quadrature voltage controlled oscillator | |
| CN109510597B (en) | Broadband enhancement type injection locking quad-frequency device | |
| CN115498962B (en) | Low-phase-noise crystal oscillator circuit and implementation method | |
| TW201310892A (en) | Low noise oscillators | |
| Yu et al. | A wideband CMOS frequency quadrupler with transformer-based tail feedback loop | |
| US6933794B2 (en) | Voltage-controlled oscillator and electronic device using same | |
| CN116488584B (en) | High-frequency spectrum purity frequency multiplication crystal oscillator circuit | |
| CN116961588B (en) | Low-noise frequency multiplication crystal oscillator circuit | |
| CN115051650B (en) | S-band frequency-doubling low-phase-noise voltage-controlled oscillator and signal generating device | |
| CN111147021B (en) | Voltage controlled oscillator | |
| JP3762645B2 (en) | Injection-locked oscillator, oscillator, and high-frequency communication device using them | |
| JP2003087052A (en) | Frequency synthesizer | |
| CN217508714U (en) | Voltage-controlled oscillator and signal generating device of frequency doubling band low phase noise | |
| CN116886046B (en) | Voltage-controlled oscillating circuit | |
| CA2212821C (en) | High stability single-port saw resonator oscillator | |
| CN212785265U (en) | Heap colpitts oscillator | |
| TW202103450A (en) | Injection locked divide-by-three frequency divider providing an injection locked frequency divider that has a wide frequency locking range and low power consumption | |
| CN107666284A (en) | A kind of high frequency crystal oscillator | |
| KR100844457B1 (en) | Colpitts quadrature voltage controlled oscillator | |
| RU2207705C1 (en) | Controllable crystal oscillator incorporating provision of high-ratio frequency multiplication | |
| Naik et al. | A 1.8 V Quadrature Phase LC Oscillator for 5G Applications | |
| CN118100802A (en) | Millimeter wave frequency band three-coil coupled oscillator structure and chip |
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 |