A voltage-controlled oscillator and signal generating device with low phase noise in the frequency doubling band

Abstract

The present invention discloses a voltage-controlled oscillator and signal generator with low phase noise in the octave band, belonging to the field of circuit design technology. The device comprises a coupled resonant cavity network, including a first coupled resonator and a second coupled resonator, which generate signals of different resonant frequencies under the control of a tuning voltage; a transistor, the emitter of which is respectively connected to the output ends of the first coupled resonator and the second coupled resonator, for amplifying the resonant frequency signals; and a broadband negative resistance network, connected to the base of the transistor, for generating a uniform or constant negative resistance across the tuning band. The coupled resonant cavity network of the present invention provides the required oscillation frequency, and the negative resistance network is coupled to the base of the transistor to provide a negative resistance value that varies uniformly across the entire passband, thereby ensuring that the VCO can maintain stable oscillation throughout the entire S-band while maintaining good noise performance.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit design, and in particular to a voltage-controlled oscillator and a signal generating device with low phase noise in an octave band. Background Art

[0002] A voltage-controlled oscillator (VCO) is an oscillator circuit whose output frequency is proportional to the input control voltage. The magnitude of the output signal depends on the design of the VCO circuit, while the operating frequency is determined by the resonator that provides the input signal. Clock generation and recovery circuits typically use the VCO within a phase-locked loop (PLL) as an external reference to generate the clock. Therefore, the VCO is crucial to the performance of the PLL. PLLs are particularly important in wireless networks because they enable communications equipment to quickly lock onto the carrier frequency being transmitted.

[0003] The dynamic operating range and noise performance of a voltage-controlled oscillator (VCO) can limit or impact the performance of the phase-locked loop (PLL), and thus the performance of devices incorporating the PLL. For example, the performance of RF transceivers, mobile phones, and modem cards is affected by the VCO's performance. Wideband tunability of the VCO is one of the most fundamental performance considerations in VCO design, and it depends on the technology and topology used. The dynamic time-averaged quality factor (Q factor) of the resonant cavity (generally inversely proportional to the VCO's operating frequency range) and the noise of the tuning diode affect the VCO's noise performance.

[0004] Current developments in RF technology place higher demands on VCO design: low phase noise, low power consumption, and a wide frequency tuning range. Despite continuous improvements in VCO technology, low phase noise remains a bottleneck. Existing technologies have the following main drawbacks and deficiencies:

[0005] 1. From the perspective of tuning bandwidth, existing LC resonator-based VCOs do not yet have a tuning range that covers the entire S-band. While YIG resonator-based VCOs can achieve a wider tuning range, they are expensive and bulky, which presents certain drawbacks for today's miniaturization needs.

[0006] 2. From the perspective of phase noise, the phase noise level of VCOs with wider bandwidth operating near the S band is generally around -80dBc / Hz@10kHz, and the phase noise level still needs to be improved.

[0007] In summary, the invention of a voltage-controlled oscillator with a multiplication band and low phase noise is very necessary. Summary of the Invention

[0008] The purpose of the present invention is to overcome the problems of the prior art and provide a voltage-controlled oscillator and a signal generating device with low phase noise in the frequency doubling band.

[0009] The object of the present invention is achieved through the following technical solution: a voltage-controlled oscillator with low phase noise in the frequency doubling band, the voltage-controlled oscillator comprising a coupled resonant cavity network, a quartz crystal, i.e., a transistor, and a broadband negative resistance network.

[0010] The coupled resonant cavity network includes a first coupled resonator and a second coupled resonator, and the first coupled resonator and the second coupled resonator generate different resonant frequency signals under the control of a tuning voltage. Specifically, the tuning voltage is provided by a power supply module or device with an adjustable output voltage, and its value is 0V-20V. The two coupled resonators are used to generate a resonant frequency, and can be LC oscillators, RC oscillators, etc., and different resonant frequencies will be generated under different tuning voltage excitations. Preferably, the first coupled resonator and the second coupled resonator use the same resonator and generate the same resonant frequency under the same tuning voltage excitation.

[0011] The emitters of the transistors are connected to the output terminals of the first and second coupled resonators, respectively, for amplifying the resonant frequency signal. The VCO operating frequency is output by the collectors of the transistors. Specifically, the VCO of the present invention uses parallel-emitter transistors for amplification. Two identical tuning networks (coupled resonators) are coupled to the emitters of the parallel-emitter transistors. The two oscillation frequencies of equal amplitude and opposite phase suppress odd-order modes and superimpose even-order modes, enabling an output frequency adjustable within a range of twice the fundamental frequency, thereby increasing the tuning frequency range.

[0012] A broadband negative resistance network is connected to the base of the transistor and is used to maintain a constant resistance throughout the entire passband of the resonant cavity. Specifically, while changing the oscillation frequency of the coupled resonant cavity network and thus the VCO operating frequency by tuning the voltage, the negative resistance network generates a uniform or constant negative resistance across the tuning band, thereby ensuring that the VCO can maintain stable oscillation throughout the entire S-band while maintaining good noise performance.

[0013] In one example, according to the oscillation principle of a negative resistance circuit (broadband negative resistance network), the oscillation starting conditions of the circuit are:

[0014] R IN +R L <0

[0015] Among them, R IN Represents the real part of the input impedance; R L represents the real part of the load impedance; the condition for oscillation balance is:

[0016] R IN =-R L , and X IN =-X L

[0017] Among them, X INrepresents the imaginary part of the input impedance; X L Represents the imaginary part of the load impedance. In practical applications, it is usually necessary to meet the following requirements:

[0018] R L =-R IN / 3

[0019] However, ensuring that the negative resistance of the circuit meets the oscillation conditions within a wide passband is a difficulty in current broadband VCO design. The impedance calculation formula for the 1.6G-4.1G frequency band of the present invention is:

[0020] Zin=Vin / Iin

[0021] Where Vin is the input voltage; Iin is the input current. After performing AC equivalent on the transistor circuit, we get:

[0022] Zin=[(1+β)X c X vr +h ie (X c +X vr )] / X c +h ie

[0023] Among them, β is the parameter that characterizes the current amplification capability of the transistor; Xc is the equivalent capacitive reactance of the negative resistance circuit; X vr is the equivalent capacitive reactance of the varactor diode; h ie It is the input resistance of the transistor output when AC is short-circuited, and is used to reflect the control ability of the base voltage on the base current when the output voltage Uce remains unchanged. c <<h ie Sometimes:

[0024] Zin≈(1+β) / h ie *X c X vr +(X c +X vr )=-gm / ω2C*C vr +1 / jω(C*C vr / (C+C vr ))

[0025] R IN =-gm / ω 2 C*C vr ,X IN =1 / jω(C*C vr / (C+C vr ))

[0026] Where gm represents the control capability of the transistor input voltage on the output current, i.e., the amplification effect; C is the equivalent capacitance of the negative resistance circuit; Cvr is the equivalent capacitance of the varactor diode. After the impedance that meets the 1.6G-4.1G frequency band is obtained by calculation, the load impedance and input impedance are made to meet the starting conditions, and then a negative resistance circuit that meets the impedance required for the 1.6G-4.1G frequency band is constructed based on capacitance and inductance. As a preferred embodiment, the broadband negative resistance network inductor L9, one end of the inductor L9 is connected to a grounded capacitor C10, the other end is connected to a grounded capacitor C11, and an inductor L10 is connected between the inductor L9 and the grounded capacitor C10, and the other end of the inductor L10 is connected to a grounded capacitor C12, the values of L9, L10, C10, C11, and C12 are specifically based on the impedance required to meet the 1.6G-4.1G frequency band, and under the condition that the impedance requirements can be met, the value of the capacitance is increased as much as possible to reduce phase noise.

[0027] In one example, the voltage-controlled oscillator further includes a filter network for filtering the tuning voltage to remove clutter signals in the tuning voltage, thereby improving the anti-interference capability of the VCO.

[0028] In one example, the filter network is an LC filter circuit. As a preferred option, the LC filter circuit includes a first LC filter subcircuit and a second LC filter subcircuit, and the tuning voltage is filtered by the first LC filter subcircuit and the second LC filter subcircuit respectively and then input to the first coupled resonator and the second coupled resonator accordingly. Specifically, the first LC filter subcircuit includes an inductor L6 and an inductor L5 connected in series, a grounded capacitor C7 is connected between the inductor L6 and the inductor L5, and the other end of the inductor L5 (the end away from the inductor L6) is connected to the grounded capacitor C6. The second LC filter subcircuit includes an inductor L8 and an inductor L7 connected in series, a grounded capacitor C9 is connected between the inductor L8 and the inductor L7, and the other end of the inductor L7 (the end away from the inductor L8) is connected to the grounded capacitor C8.

[0029] In one example, both the first coupled resonator and the second coupled resonator are LC oscillators, and the resonant frequency f satisfies:

[0030]

[0031] Wherein, L represents the inductance value of the oscillator; C represents the capacitance value of the oscillator.

[0032] In one example, the LC oscillator includes two varactors connected in parallel, with a microstrip line disposed between the two varactors. The output of the LC oscillator is connected between the microstrip line and one of the varactors. In this example, the use of two varactors connected in parallel increases the capacitance variation range of the varactors, thereby broadening the VCO's tuning frequency range to cover the entire S-band.

[0033] In one example, the two varactor diodes in the LC oscillator have identical specifications. Specifications here refer to the varactor's performance parameters, including its capacitance. In this example, the Q value of two identical varactor diodes connected in parallel is the same as that of a single varactor diode, which does not degrade phase noise and achieves low-noise output.

[0034] In one example, the microstrip line is an arc-shaped microstrip line. In this case, the model expression of the LC oscillator composed of two parallel-connected varactor diodes and a microstrip line is:

[0035]

[0036] At this time, the F factor is expressed as:

[0037]

[0038] In the above two equations, Δω represents the change in angular frequency; T represents temperature; R represents the loss resistance in the LC oscillator; V0 represents the output voltage; Q represents the dynamic time-averaged quality factor of the resonant cavity; ω0 represents the initial angular frequency; I T represents the tail current; g m,tail represents the transconductance of the tail current source transistor; γ represents the transistor noise figure. In a resonant network, the Q of the inductor is much lower than that of the MIM capacitor and varactor diode. Therefore, the Q of the resonant network (coupled resonant cavity network) is primarily determined by the spiral inductor. Therefore, to improve the Q of the resonant network, it is important to select an inductor with a high Q value. In this example, the equivalent inductance generated by a curved microstrip line is used for resonance, effectively improving the inductor's Q.

[0039] In one example, the first coupled resonator and the second coupled resonator use varactor diodes and microstrip lines of the same specifications. At this time, the circuit from the tuning voltage to the two resonators to the transistor emitter is completely mirrored, so the outputs of the two resonators are exactly the same during the Vt change process, ensuring the efficiency of signal coupling.

[0040] In one example, the voltage-controlled oscillator further includes an output matching network connected to the collector of the transistor, thereby obtaining a stable operating frequency at the output end of the output matching network.

[0041] In one example, the output matching network includes a first capacitor for matching the transistor output terminal with the subsequent stage, as well as a capacitor and inductor for impedance matching the output terminal of the voltage-controlled oscillator. As a preferred embodiment, the output matching network includes a capacitor C3, a resistor R1, a capacitor C2, and a capacitor C1 connected in sequence, with a ground inductor L2 provided between the resistor R1 and the capacitor C2, and a ground inductor L1 provided between the capacitor C2 and the capacitor C1. Among them, C3 is used to match the transistor output terminal with the subsequent stage and also for DC isolation. C1, C2, L1, and L2 match the output impedance line to take into account errors in actual engineering.

[0042] In one example, the voltage-controlled oscillator further includes a DC power supply network connected to the broadband negative resistance network and the base of the transistor. Preferably, the DC power supply network voltage VCC is sequentially connected to resistors R2 and R3, with the other end of resistor R3 connected to the broadband negative resistance network. A grounded capacitor C4 is also connected between resistors R2 and R3. Furthermore, resistors R2 and R3 are further connected to an inductor L3, with one end of inductor L3 connected to one side of grounded capacitor C4 and the other end of inductor L3 connected to grounded capacitor C5. A connection between inductor L3 and capacitor C5 is made between the collector of the transistor.

[0043] The present invention also includes a signal generating device, which includes a voltage-controlled oscillator formed by any one of the above examples or a plurality of examples, and is used to generate a specific frequency signal.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. In one example, the coupled resonant cavity network of the present invention provides the required oscillation frequency, and the negative resistance network is coupled to the base of the transistor to provide a negative resistance value that varies uniformly throughout the passband, thereby ensuring that the VCO can maintain stable oscillation throughout the entire S-band while maintaining good noise performance.

[0046] 2. In one example, a filter network is used to filter out clutter signals in the tuning voltage, thereby improving the anti-interference capability of the VCO.

[0047] 3. In one example, using two varactor diodes connected in parallel can increase the capacitance variation range of the varactor diodes, thereby widening the tuning frequency range of the VCO to cover the entire S-band.

[0048] 4. In one example, the Q value of two identical varactor diodes connected in parallel is the same as the Q value of a single varactor diode, which does not deteriorate the phase noise and achieves low-noise output.

[0049] 5. In one example, the equivalent inductance obtained based on the arc-shaped microstrip line is resonated, effectively improving the Q value of the inductor.

[0050] 6. In one example, using resonators of the same specifications can output the same resonant frequency to the transistor emitter when the tuning voltage changes, ensuring signal coupling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The same reference numerals are used in these drawings to represent the same or similar parts. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application.

[0052] Figure 1 A system block diagram in an example of the present invention;

[0053] Figure 2 is a circuit schematic diagram of a coupled resonant cavity network and a filter network in an example of the present invention;

[0054] Figure 3 A schematic circuit diagram of a broadband negative resistance network and a DC power supply network in an example of the present invention;

[0055] Figure 4 is a circuit schematic diagram of an output matching network in an example of the present invention;

[0056] Figure 5 A noise test diagram in an example of the present invention;

[0057] Figure 6 This is a noise test diagram in another example of the present invention. DETAILED DESCRIPTION

[0058] The technical solution of the present invention is described clearly and completely below with reference to the accompanying drawings. It is apparent that the embodiments described are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0059] In the description of the present invention, it should be noted that the directions or positional relationships indicated by "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the directions or positional relationships described in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the use of ordinal numbers (for example, "first and second", "first to fourth", etc.) is for the purpose of distinguishing objects and is not limited to this order, and cannot be understood as indicating or implying relative importance.

[0060] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention.

[0061] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0062] A voltage controlled oscillator with low phase noise in the frequency octave band, a preferred example of which is as follows Figure 1 As shown, it includes a coupled resonant cavity network, an NPN transistor, a broadband negative resistance network, a filtering network, an output matching network and a DC power supply network.

[0063] like Figure 2 As shown, the coupled resonant cavity network includes a first coupled resonator and a second coupled resonator with identical circuit structures. The first coupled resonator includes a first varactor diode VR1 and a second varactor diode VR2 connected in parallel, with a first curved microstrip line provided between the cathodes of the first varactor diode VR1 and the cathodes of the second varactor diode VR2, and the emitter of the transistor connected between the first curved microstrip line and the cathode of the second varactor diode VR2. The second coupled resonator includes a third varactor diode VR3 and a fourth varactor diode VR4 connected in parallel, with a second curved microstrip line provided between the cathodes of the third varactor diode VR3 and the cathodes of the fourth varactor diode VR4, and the emitter of the transistor connected between the second curved microstrip line and the cathode of the fourth varactor diode VR4.

[0064] Furthermore, if Figure 2 As shown, the filter network is an LC filter circuit, comprising a first LC filter sub-circuit and a second LC filter sub-circuit. The first LC filter sub-circuit comprises inductors L6 and L5 connected in series, with a grounded capacitor C7 connected between them. The other end of inductor L5 (the end away from inductor L6) is also connected to grounded capacitor C6. The second LC filter sub-circuit comprises inductors L8 and L7 connected in series, with a grounded capacitor C9 connected between them. The other end of inductor L7 (the end away from inductor L8) is also connected to grounded capacitor C8. The tuning voltage Vt is filtered by the first and second LC filter sub-circuits before being applied to four varactors, which have identical specifications.

[0065] Furthermore, if Figure 3As shown, the broadband negative resistance network inductor L9, one end of the inductor L9 is connected to the grounded capacitor C10, the other end of the inductor L9 is connected to the grounded capacitor C11, and the inductor L10 is connected between the inductor L9 and the grounded capacitor C10, the other end of the inductor L10 is connected to the grounded capacitor C12, and the capacitor L9 and the grounded capacitor C11 are connected to the base of the transistor.

[0066] Furthermore, if Figure 3 As shown, the voltage VCC of the DC power supply network is sequentially connected to resistors R2 and R3, and the other end of the resistor R3 is connected to the grounded capacitor C10; a grounded capacitor C4 is also connected between the resistors R2 and R3, and an inductor L3 is also connected to the resistors R2 and R3, one end of the inductor L3 is connected to one side of the grounded capacitor C4, and the other end of the inductor L3 is connected to the grounded capacitor C5, and the collector of the transistor is connected between the inductor L3 and the capacitor C5.

[0067] Furthermore, if Figure 4 As shown in the figure, the output matching network consists of capacitor C3, resistor R1, capacitor C2, and capacitor C1, connected in sequence. The other end of capacitor C3 is connected to the collector of the transistor. A grounding inductor L2 is provided between resistor R1 and capacitor C2, and a grounding inductor L1 is provided between capacitors C2 and C1. The VCO operating frequency is output from capacitor C1. C3 matches the transistor output with the subsequent stage and also provides DC isolation. C1, C2, L1, and L2 match the 50Ω impedance line at the output to account for errors in actual projects.

[0068] In this example, the tuning voltage Vt is varied to change the capacitance of the varactor, thereby varying the resonant frequency of the resonator. This, in turn, changes the VCO operating frequency. The negative resistance network produces a uniform or constant negative resistance across the tuning frequency band. Combined with the aforementioned horseshoe-shaped resonant cavity structure, a voltage-controlled oscillator (VCO) with a 1.6-4.1GHz frequency band, covering the entire S-band, and a phase noise of -90dBc / Hz at 10kHz, is designed.

[0069] The VCO was fabricated using a Rogers 5880 printed circuit board (PCB) with a thickness of 0.8 mm. Based on the aforementioned principles and layout, the test results of the actual circuit designed are as follows:

[0070] When the Vt voltage is 0V, the output frequency is 1.599GHz, the harmonic suppression is less than 15, and the output power is 4.1dBm; when the Vt voltage is 18V, the output frequency is 4.195GHz, the harmonic suppression is less than 40, and the output power is 2.1dBm. As the voltage increases, the frequency gradually increases, the harmonic suppression gradually improves, and the output power gradually decreases. According to the noise test chart Figure 5It can be seen that the phase noise of the voltage-controlled oscillator can reach -92.67dBc / Hz at a 10KHz offset, -109.50dBc / Hz at a 100KHz offset, and -128.91dBc / Hz at a 1MHz offset.

[0071] In another example, the same circuit principle as the above example is used. Calculate the value of the varactor diode in the resonant cavity at the required output frequency, that is, the inductor of the oscillator; according to R L =-R IN / 3,X IN =-X L Calculate the values of the capacitor and inductor in the negative resistance network to realize voltage-controlled oscillators with outputs in other frequency bands. For example, a 3GHz-6GHz voltage-controlled oscillator. At this time, when the Vt voltage is 0V, the output frequency is 2.760GHz, the harmonic suppression is <15, and the output power is 3.44dBm; when the Vt voltage is 18V, the output frequency is 6.300GHz, the harmonic suppression is <20, and the output power is -0.9dBm. As the voltage increases, the frequency gradually increases, the harmonic suppression gradually increases, and the output power gradually decreases. Based on the noise test graph Figure 6 It can be seen that the phase noise of the voltage-controlled oscillator at a 10KHz offset is calculated according to the phase noise calculation formula. The specific calculation formula is:

[0072] L(Δω)=(Pn)dBm-(Psig)dBm-10lg(Δf)

[0073] Where L(Δω) represents the phase noise of the output frequency; Pn represents the effective power of the signal; Psig represents the effective power of the spectrum analyzer noise floor, which is given by Figure 6 In this example, the value of (Pn)dBm - (Psig)dBm is 54.47dB. Δf represents the resolution bandwidth (RES BW), which is 1 kHz in this example. Based on this phase noise calculation formula, the phase noise of the voltage-controlled oscillator at a 10 kHz offset is calculated to be -84.47dBc / Hz.

[0074] The above specific implementation methods are detailed descriptions of the present invention. It cannot be considered that the specific implementation methods of the present invention are limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, they can make several simple deductions and substitutions without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A voltage-controlled oscillator with low phase noise in the frequency octave band, characterized by: The voltage controlled oscillator comprises: A coupled resonant cavity network includes a first coupled resonator and a second coupled resonator, wherein the first coupled resonator and the second coupled resonator generate signals of different resonant frequencies under the control of a tuning voltage; The first coupled resonator and the second coupled resonator are both LC oscillators; The LC oscillator includes two varactor diodes connected in parallel, with a microstrip line provided between the two varactor diodes; The specifications of the two varactor diodes in the LC oscillator are the same; The first coupled resonator and the second coupled resonator use varactor diodes and microstrip lines of the same specifications; a transistor, wherein the emitter of the transistor is connected to the output end of the first coupled resonator and the output end of the second coupled resonator, respectively, and is used to amplify the resonant frequency signal; a broadband negative resistance network connected to the base of the transistor for generating a uniform or constant negative resistance over the tuning frequency band; The impedance calculation formula for the 1.6G-4.1G frequency band is: Zin≈(1+β) / h ie *X c X vr +(X c +X vr )=-gm / ω2C*C vr +1 / jω(C*C vr / (C+C vr )) R IN =-gm / ω 2 C*C vr ,X IN =1 / jω(C*C vr / (C+C vr )) Among them, β is the parameter that characterizes the current amplification capability of the transistor; h ie is the input resistance of the transistor output when the AC short circuit occurs, which is used to reflect the control ability of the base voltage on the base current when the output voltage Uce remains unchanged; Xc is the equivalent capacitive reactance of the negative resistance circuit; X vr is the equivalent capacitive reactance of the varactor diode; gm represents the control capability of the transistor input voltage on the output current, i.e., the amplification effect; C is the equivalent capacitance of the negative resistance circuit; C vr is the equivalent capacitance of the varactor diode; R IN represents the real part of input impedance; X IN represents the imaginary part of the input impedance; The load impedance and input impedance are made to meet the oscillation conditions, and then a negative resistance circuit that meets the impedance required by the 1.6G-4.1G frequency band is constructed based on capacitors and inductors.

2. The voltage-controlled oscillator with low phase noise in the octave band according to claim 1, characterized in that: The voltage controlled oscillator further includes a filter network for filtering the tuning voltage.

3. The voltage-controlled oscillator with low phase noise in the octave band according to claim 2, characterized in that: The filtering network is an LC filtering circuit.

4. The voltage-controlled oscillator with low phase noise in the octave band according to claim 1, characterized in that: The microstrip line is an arc-shaped microstrip line.

5. The voltage-controlled oscillator with low phase noise in an octave band according to claim 1, characterized in that: The voltage controlled oscillator further includes an output matching network connected to the collector of the transistor.

6. A signal generating device, characterized in that: The device comprises the voltage-controlled oscillator according to any one of claims 1 to 5.

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