Millimeter wave voltage-controlled oscillator and oscillation mode control method thereof

Abstract

The invention discloses a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof. The voltage-controlled oscillator comprises a first low-frequency oscillator, a second low-frequency oscillator, a first high-frequency oscillator, a second high-frequency oscillator, a first inductor, a second inductor, a third inductor, a fourth inductor and an odd-even mode switch control module. The odd-even mode switch control module can control the first low-frequency oscillator and the second low-frequency oscillator to work in a low-frequency even mode or a low-frequency odd mode, and control the voltage-controlled oscillator to work in a low-frequency even mode or a high-frequency odd mode. By changing the current directions of the first low-frequency oscillator and the second low-frequency oscillator as well as the first high-frequency oscillator and the second high-frequency oscillator, two oscillation modes, namely an even mode and an odd mode, can be respectively realized at high frequency and low frequency by combining with the third circle of inductor, and finally continuous tuning of the four oscillation modes is realized; the tuning range of the voltage-controlled oscillator can be expanded, and the phase noise performance of the voltage-controlled oscillator can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuits, and in particular to a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof. Background Art

[0002] As the core module in the communication system, the voltage controlled oscillator (VCO) is a broadband transceiver that can support operation in the millimeter wave band. It can provide local oscillator signals for the transmission and reception links, as well as clock signals for modules such as communication interfaces and baseband processors.

[0003] Existing voltage-controlled oscillators are usually dual-core dual-mode voltage-controlled oscillators and quad-core quad-mode oscillators. In a dual-core dual-mode voltage-controlled oscillator, the oscillator can switch between even mode and odd mode, and the frequency tuning range of the oscillator is expanded based on whether the coupling capacitor array is connected. However, the added coupling capacitor array increases the loss of the resonant cavity, which will reduce the phase noise performance of the voltage-controlled oscillator. In addition, only two switching modes also limit the maximum achievable frequency tuning range. In a quad-core quad-mode oscillator, the oscillator realizes magnetic coupling through a transformer and realizes electrical coupling through a coupling capacitor array. At the same time, a two-dimensional mode switch is used to change the odd and even of the current direction between the four cores, so that the equivalent of the transformer or the equivalent of the coupling capacitor array changes, thereby realizing four oscillation modes. However, the added coupling capacitor array still increases the loss of the loop, which reduces the phase noise performance of the voltage-controlled oscillator.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof, so as to solve the problem that the existing voltage-controlled oscillator uses a coupling capacitor array to increase loop loss and cause phase noise performance degradation.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a millimeter wave voltage-controlled oscillator, comprising: a first low-frequency oscillator, a second low-frequency oscillator, a first high-frequency oscillator, a second high-frequency oscillator, a first inductor, a second inductor, a third inductor, a fourth inductor and an odd-even mode switch control module;

[0008] The odd-even mode switch control module is connected between the first low frequency oscillator and the second low frequency oscillator and between the first high frequency oscillator and the second high frequency oscillator;

[0009] The first inductor and the second inductor are coupled to the first low-frequency oscillator and the first high-frequency oscillator respectively; the third inductor and the fourth inductor are coupled to the second low-frequency oscillator and the second high-frequency oscillator respectively;

[0010] The odd-even mode switch control module is used to control the first low frequency oscillator and the second low frequency oscillator to operate in a low frequency even mode or a low frequency odd mode, and is used to control the first high frequency oscillator and the second high frequency oscillator to operate in a high frequency even mode and a high frequency odd mode.

[0011] According to a further configuration of the present invention, the odd-even mode switch control module includes: a first low-frequency even mode switch, a second low-frequency even mode switch, a first low-frequency odd mode switch, a second low-frequency odd mode switch, a first high-frequency even mode switch, a second high-frequency even mode switch, a first high-frequency odd mode switch and a second high-frequency odd mode switch; wherein,

[0012] The first low-frequency even-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; the second low-frequency even-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator;

[0013] The first low-frequency odd-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; the second low-frequency odd-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator;

[0014] The first high-frequency even-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator; the second high-frequency even-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator;

[0015] The first high-frequency odd-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator; the second high-frequency odd-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator.

[0016] According to a further configuration of the present invention, the first low frequency oscillator comprises: a first transistor, a second transistor, a fifth inductor, a sixth inductor, a first capacitor array and a second capacitor array; wherein,

[0017] The gate of the first transistor is connected to the drain of the second transistor, the drain of the first transistor is connected to the gate of the second transistor and one end of the fifth inductor respectively, and the source of the first transistor is connected to the source of the second transistor;

[0018] The drain of the second transistor is also connected to one end of the sixth inductor;

[0019] The other end of the fifth inductor is respectively connected to the low-frequency power supply end and the first low-frequency even-mode switch and the first low-frequency odd-mode switch;

[0020] The other end of the sixth inductor is connected to the low-frequency power supply end and the second low-frequency even-mode switch and the second low-frequency odd-mode switch respectively;

[0021] One end of the first capacitor array is connected to one end of the fifth inductor, and the other end of the first capacitor array is connected to one end of the sixth inductor; the second capacitor array is connected in parallel with the first capacitor array.

[0022] According to a further configuration of the present invention, the second low frequency oscillator comprises: a third transistor, a fourth transistor, a seventh inductor, an eighth inductor, a third capacitor array and a fourth capacitor array; wherein,

[0023] The drain of the third transistor is connected to the gate of the fourth transistor and one end of the seventh inductor respectively, the gate of the third transistor is connected to the drain of the fourth transistor, and the source of the third transistor is connected to the source of the fourth transistor;

[0024] The drain of the fourth transistor is also connected to one end of the eighth inductor;

[0025] The other end of the seventh inductor is connected to the first low-frequency even-mode switch and the second low-frequency odd-mode switch respectively;

[0026] The other end of the eighth inductor is connected to the first low-frequency odd-mode switch and the second low-frequency even-mode switch respectively.

[0027] According to a further configuration of the present invention, the first high frequency oscillator comprises: a fourth transistor, a fifth transistor, a ninth inductor, a tenth inductor, a fifth capacitor array and a sixth capacitor array; wherein,

[0028] The gate of the fourth transistor is connected to the drain of the fifth transistor, the drain of the fourth transistor is respectively connected to the gate of the fifth transistor and one end of the ninth inductor, and the source of the fourth transistor is connected to the source of the fifth transistor;

[0029] The drain of the fifth transistor is also connected to one end of the tenth inductor;

[0030] The other end of the ninth inductor is respectively connected to the high-frequency power supply end, the first high-frequency even-mode switch, and the first high-frequency odd-mode switch;

[0031] The other end of the tenth inductor is respectively connected to the high-frequency power supply end, the second high-frequency even-mode switch and the second high-frequency odd-mode switch;

[0032] One end of the fifth capacitor array is connected to one end of the ninth inductor, and the other end of the fifth capacitor array is connected to one end of the tenth inductor; the sixth capacitor array is connected in parallel with the fifth capacitor array.

[0033] According to a further configuration of the present invention, the second high frequency oscillator comprises: a seventh transistor, an eighth transistor, an eleventh inductor, a twelfth inductor, a seventh capacitor array and an eighth capacitor array; wherein,

[0034] The gate of the seventh transistor is connected to the drain of the eighth transistor, the drain of the seventh transistor is respectively connected to the gate of the eighth transistor and one end of the eleventh inductor, and the source of the seventh transistor is connected to the source of the eighth transistor;

[0035] The drain of the eighth transistor is also connected to one end of the twelfth inductor;

[0036] The other end of the eleventh inductor is respectively connected to the first high-frequency even-mode switch and the second high-frequency odd-mode switch;

[0037] The other end of the twelfth inductor is respectively connected to the second high-frequency even-mode switch and the first high-frequency odd-mode switch;

[0038] One end of the seventh capacitor array is connected to one end of the eleventh inductor, and the other end of the eighth capacitor array is connected to one end of the twelfth inductor; the eighth capacitor array is connected in parallel with the seventh capacitor array.

[0039] According to a further configuration of the present invention, the millimeter wave voltage-controlled oscillator further includes: a first common-mode secondary resonance bandwidth extension module and a second common-mode secondary resonance bandwidth extension module;

[0040] The first common-mode secondary resonance bandwidth extension module is connected to the first low-frequency oscillator and the second low-frequency oscillator respectively, and the first common-mode secondary resonance bandwidth extension module is used to improve the phase noise performance in the low-frequency mode;

[0041] The second common-mode secondary resonance bandwidth extension module is connected to the first high-frequency oscillator and the second high-frequency oscillator respectively, and the second common-mode secondary resonance bandwidth extension module is used to improve the phase noise performance in the high-frequency mode.

[0042] According to a further configuration of the present invention, the first common-mode secondary resonance bandwidth extension module includes: a thirteenth inductor, a fourteenth inductor, a first capacitor and a second capacitor; wherein,

[0043] One end of the thirteenth inductor is connected to the first low-frequency oscillator and the second low-frequency oscillator respectively, and the other end of the thirteenth inductor is grounded;

[0044] One end of the fourteenth inductor is connected to one end of the first capacitor, and the other end of the fourteenth inductor is connected to one end of the second capacitor;

[0045] The thirteenth inductor is coupled to the fourteenth inductor;

[0046] The other end of the first capacitor is grounded; the other end of the second capacitor is grounded.

[0047] According to a further configuration of the present invention, the second common-mode secondary resonance bandwidth extension module includes: a fifteenth inductor, a sixteenth inductor, a third capacitor and a fourth capacitor; wherein,

[0048] One end of the fifteenth inductor is connected to the first high-frequency oscillator and the second high-frequency oscillator respectively, and the other end of the fifteenth inductor is grounded;

[0049] One end of the sixteenth inductor is connected to one end of the third capacitor, and the other end of the sixteenth inductor is connected to one end of the fourth capacitor;

[0050] The fifteenth inductor is coupled to the sixteenth inductor;

[0051] The other end of the third capacitor is grounded; the other end of the fourth capacitor is grounded.

[0052] In a second aspect, the present invention further provides an oscillation mode control method based on the above-mentioned millimeter wave voltage-controlled oscillator, which comprises:

[0053] When the voltage-controlled oscillator is required to be in a low-frequency oscillation mode, the first low-frequency oscillator and the second low-frequency oscillator are controlled to work, the first high-frequency oscillator and the second high-frequency oscillator are controlled not to work, and the current directions of the first low-frequency oscillator and the second low-frequency oscillator are changed by the odd-even mode switch control module, so that the voltage-controlled oscillator is in a low-frequency even mode or a low-frequency odd mode;

[0054] When the voltage-controlled oscillator is required to be in a high-frequency oscillation mode, the first high-frequency oscillator and the second high-frequency oscillator are controlled to work, the first low-frequency oscillator and the second low-frequency oscillator are controlled not to work, and the current directions of the first high-frequency oscillator and the second high-frequency oscillator are changed through the odd-even mode switch control module, so that the voltage-controlled oscillator is in a high-frequency even mode or a high-frequency odd mode.

[0055] The present invention provides a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof. The millimeter wave voltage-controlled oscillator comprises: a first low-frequency oscillator, a second low-frequency oscillator, a first high-frequency oscillator, a second high-frequency oscillator, a first inductor, a second inductor, a third inductor, a fourth inductor and an odd-even mode switch control module; the first inductor and the second inductor are coupled to the first low-frequency oscillator and the first high-frequency oscillator respectively; the third inductor and the fourth inductor are coupled to the second low-frequency oscillator and the second high-frequency oscillator respectively. The odd-even mode switch control module can control the first low-frequency oscillator and the second low-frequency oscillator to work in a low-frequency even mode or a low-frequency odd mode. When the voltage-controlled oscillator is controlled to be in a low-frequency working mode or a high-frequency working mode, the current directions of the first low-frequency oscillator and the second low-frequency oscillator and the first high-frequency oscillator and the second high-frequency oscillator can be changed, so that the first inductor, the second inductor, the third inductor, and the fourth inductor have two different magnetic coupling modes for the first low-frequency oscillator, the second low-frequency oscillator, the first high-frequency oscillator, and the second high-frequency oscillator, thereby realizing two oscillation modes, an even mode and an odd mode, and finally realizing four oscillation modes, an odd mode and an even mode oscillating at a lower frequency and an odd mode and an even mode oscillating at a higher frequency. The present invention realizes four oscillation modes by inductive coupling, and while expanding the tuning range of the voltage-controlled oscillator, improves the phase noise performance of the voltage-controlled oscillator relative to the use of capacitor array coupling. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0057] Figure 1 It is a schematic diagram of the overall structure of the millimeter wave voltage-controlled oscillator in the present invention.

[0058] Figure 2 It is the transformer loop model and its frequency response diagram in the present invention.

[0059] Figure 3 It is a schematic diagram of the working state of the odd-even mode in the low-frequency mode of the present invention.

[0060] Figure 4 It is a circuit schematic diagram of the millimeter wave voltage-controlled oscillator in the present invention.

[0061] Figure 5 It is a tuning curve diagram of four oscillation modes of the millimeter wave voltage-controlled oscillator in the present invention.

[0062] Figure 6 It is a schematic diagram of the first common-mode secondary resonance bandwidth extension module in the present invention.

[0063] Figure 7 It is a flow chart of the resonance mode control method of the millimeter wave voltage-controlled oscillator in the present invention.

[0064] The marks in the accompanying drawings are: 100, a first low-frequency oscillator; 200, a second low-frequency oscillator; 300, a first high-frequency oscillator; 400, a second high-frequency oscillator; 500, an odd-even mode switch control module; 600, a first common-mode secondary resonance bandwidth extension module; 700, a second common-mode secondary resonance bandwidth extension module. DETAILED DESCRIPTION

[0065] The present invention provides a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0066] In the embodiments and the scope of the patent application, unless the text specifically defines the article, "a", "an", "the" and "the" may also include plural forms. If there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0067] It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when an element is said to be "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can also be intermediate elements. In addition, the "connection" or "coupling" used herein can include wireless connection or wireless coupling. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0068] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as herein.

[0069] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0070] The inventors have found that the working frequency bands of the fifth generation of mobile communications (5G) are mainly divided into Sub-6G and millimeter wave bands. The Sub-6G band division is concentrated in 0.45GHz to 6GHz, and the millimeter wave band division is concentrated in 24.25GHz to 43.5GHz. Compared with the Sub-6G band, the millimeter wave band can provide richer frequency resources, making ultra-high-speed mobile communications possible. 5G millimeter wave communication bands include n257 (26.5GHz-29.5GHz), n258 (24.25GHz-27.5GHz), n259 (39.5GHz-43.5GHz), n260 (37GHz-40GHz), n261 (27.5GHz-28.35GHz) and other bands.

[0071] Existing voltage-controlled oscillators are usually dual-core dual-mode voltage-controlled oscillators, quad-core quad-mode oscillators, and dual-core triple-mode oscillators. In a dual-mode voltage-controlled oscillator, the oscillator can switch between even mode and odd mode, and the frequency tuning range of the oscillator is expanded based on whether the coupling capacitor array is connected. However, the added coupling capacitor array increases the loss of the resonant cavity, which will reduce the phase noise performance of the voltage-controlled oscillator. In addition, only two switching modes also limit the maximum achievable frequency tuning range. In a quad-core quad-mode oscillator, the oscillator realizes magnetic coupling through a transformer and realizes electrical coupling through a coupling capacitor array. At the same time, a two-dimensional mode switch is used to change the odd and even of the current direction between the four cores, so that the equivalent of the transformer or the equivalent of the coupling capacitor array changes, thereby realizing four oscillation modes. The added coupling capacitor array still increases the loss of the loop, which reduces the phase noise performance of the voltage-controlled oscillator. The dual-core three-mode oscillator uses two pairs of switches to achieve odd-even mode switching of current direction between the two oscillation cores, but does not use coupling capacitors. Instead, a third turn of inductance is added to make the main loop inductance have different magnetic coupling with the third turn of inductance in odd and even modes, thereby obtaining two equivalent values ​​of the main loop inductance and realizing two different oscillation modes. This effectively avoids the loss caused by the addition of coupling capacitors while expanding the tuning range of the oscillator. In the even mode, the resonant frequency is changed by whether a capacitor is connected to the third turn of inductance, but the additional large capacitor also increases the loss and reduces the noise performance of the oscillator.

[0072] In view of the above technical problems, the present invention provides a millimeter wave voltage-controlled oscillator and an oscillation mode control method thereof. The millimeter wave voltage-controlled oscillator includes: a first low-frequency oscillator, a second low-frequency oscillator, a first high-frequency oscillator, a second high-frequency oscillator, a first inductor, a second inductor, a third inductor, a fourth inductor and an odd-even mode switch control module; the first inductor and the second inductor are coupled to the first low-frequency oscillator and the first high-frequency oscillator respectively; the third inductor and the fourth inductor are coupled to the second low-frequency oscillator and the second high-frequency oscillator respectively. The odd-even mode switch control module can control the first low-frequency oscillator and the second low-frequency oscillator to work in a low-frequency even mode or a low-frequency odd mode. When the odd-even mode switch control module controls the voltage-controlled oscillator to be in a low-frequency working mode or a high-frequency working mode, the first inductor, the second inductor, the third inductor, and the fourth inductor can be changed by changing the current direction of the first low-frequency oscillator and the second low-frequency oscillator and the current direction of the first high-frequency oscillator and the second high-frequency oscillator, so that the first inductor, the second inductor, the third inductor, and the fourth inductor have two different magnetic coupling modes for the first low-frequency oscillator, the second low-frequency oscillator, the first high-frequency oscillator, and the second high-frequency oscillator, thereby realizing two oscillation modes, the even mode and the odd mode, and finally realizing four oscillation modes, the odd mode and the even mode oscillating at a lower frequency and the odd mode and the even mode oscillating at a higher frequency. The present invention adopts the inductive coupling method to realize four oscillation modes, while expanding the tuning range of the voltage-controlled oscillator, and improving the phase noise performance of the voltage-controlled oscillator compared with the capacitor array coupling.

[0073] Please also see Figures 1 to 6 , the present invention provides a preferred embodiment of a millimeter wave voltage-controlled oscillator.

[0074] In some embodiments, see Figure 1 and Figure 4The present invention provides a millimeter wave voltage-controlled oscillator, which includes: a first low-frequency oscillator 100, a second low-frequency oscillator 200, a first high-frequency oscillator 300, a second high-frequency oscillator 400, a first inductor LC1, a second inductor LC2, a third inductor LC3, a fourth inductor LC4 and an odd-even mode switch control module 500; the odd-even mode switch control module 500 is connected between the first low-frequency oscillator 100 and the second low-frequency oscillator 200 and between the first high-frequency oscillator 300 and the second high-frequency oscillator 400; the first inductor LC 1. The second inductor LC2 is coupled to the first low frequency oscillator 100 and the first high frequency oscillator 300 respectively; the third inductor LC3 and the fourth inductor LC4 are coupled to the second low frequency oscillator 200 and the second high frequency oscillator 400 respectively; the even-odd mode switch control module 500 is used to control the first low frequency oscillator 100 and the second low frequency oscillator 200 to work in a low frequency even mode or a low frequency odd mode, and to control the first high frequency oscillator 300 and the second high frequency oscillator 400 to work in a high frequency even mode and a high frequency odd mode.

[0075] Specifically, the first low frequency oscillator 100 and the first high frequency oscillator 300 , as well as the second low frequency oscillator 200 and the second high frequency oscillator 400 are the same transformer-based single-port oscillators.

[0076] Figure 2 In the figure a is the model diagram of the transformer circuit. Figure 2 b is the frequency response diagram of the transformer circuit. Figure 2 As shown in a, the Z parameter of the low-frequency end Z11 can be expressed by the following relationship:

[0077]

[0078] Wherein, Z11 represents the frequency response function, C1 represents the capacitance of capacitor C1, L1 represents the inductance of inductor L1, ω1 and ω2 represent the frequency, k represents the coupling coefficient between L1 and L2, r L1 and r L2 represent parasitic resistance, rC1 and rC2 represent parasitic capacitance, Gm1 and Gm2 represent negative resistance, which can supplement the lost energy to maintain the oscillation; Figure 2 In, |Z 11 (ω)| and |Z 22 (ω)| represents the amplitude of the frequency response function, ∠|Z 11 (ω)| and ∠|Z 22 (ω) |The phase of the frequency response function.

[0079] Among them, L'1 can be expressed as the following formula:

[0080]

[0081] Due to the symmetry, the mathematical expressions of the low-frequency end Z11 and the high-frequency end Z22 are the same, and only the corresponding inductance and resistance values ​​need to be exchanged. The frequency response diagrams of the low-frequency end Z11 and the high-frequency end Z22 are shown in Figure 1. Figure 2 As shown in b. The frequency response diagram of the transformer's Z11 and Z22 terminals shows that the Z parameters of both Z11 and Z22 terminals have a lower frequency peak and a higher frequency peak, with a notch frequency in the middle; and the frequencies ωL and ωH of the Z parameter peaks of Z11 and Z22 terminals are the same, the difference is that the notch frequency ω1, notch of Z11 terminal is closer to the high-frequency peak, and the notch frequency ω2, notch of Z22 terminal is closer to the low-frequency peak. From the phase change of its frequency response, it can be seen that as long as appropriate transconductance is given from Z11 and Z22 terminals respectively, the loop can oscillate at both low frequency ωL and high frequency ωH. In order to avoid the ambiguity of low-frequency and high-frequency oscillation modes, it is necessary to use the notch frequency to eliminate the peak oscillation technology, and the method is to keep the ratio of the low-frequency end capacitor to the high-frequency end capacitor as large as possible. For example, when the loop oscillates at the low-frequency end, i.e., the Z11 end, the tuning capacitor at the high-frequency end, i.e., the Z22 end, needs to be set to the minimum. This will cause the notch frequency ω1, notch in the frequency response to move toward the high-frequency direction, so that the phase of the high-frequency peak ωH cannot drop to zero phase, and the loop will not oscillate at the high-frequency ωH. Similarly, when the loop oscillates at the high-frequency end, i.e., the Z11 end, the tuning capacitor at the low-frequency end, i.e., the Z22 end, needs to be set to the maximum. This will cause the notch frequency ω2, notch in the frequency response to move toward the low-frequency direction, so that the phase of the low-frequency peak ωL cannot drop to zero phase, and the loop will not oscillate at the low-frequency ωL. In this way, the ambiguity of the low-frequency and high-frequency oscillation modes can be avoided, so that the transformer-based single-port oscillator can stably oscillate at two frequencies respectively.

[0082] The first inductor LC1, the second inductor LC2, the third inductor LC3 and the fourth inductor LC4 are connected in series in sequence, and the first inductor LC1 and the second inductor LC2 are coupled to the first low-frequency oscillator 100 and the first high-frequency oscillator 300 respectively, and the third inductor LC3 and the fourth inductor LC4 are coupled to the second low-frequency oscillator 200 and the second high-frequency oscillator 400 respectively.

[0083] The odd-even mode switch control module 500 can control the first low-frequency oscillator 100 and the second low-frequency oscillator 200 to work in a low-frequency even mode or a low-frequency odd mode. When the voltage-controlled oscillator oscillates at one of the frequencies, the direction of the current in the oscillator can be changed by the odd-even mode switch control module 500, so that the third coil inductance (i.e., the first inductance LC1, the second inductance LC2, the third inductance LC3 and the fourth inductance LC4) has two different magnetic coupling modes with the main loop inductance, and two different equivalent values ​​of the main loop inductance can be obtained, so that two oscillation modes can be realized. Among them, the working principle of the first inductor LC1, the second inductor LC2, the third inductor LC3 and the fourth inductor LC4 to achieve odd-even mode switching is that the resistor RSW is the equivalent resistance after conduction; Icore1 / Icore 2 are the currents of the two oscillation cores Core 1 and Core 2 (i.e., the oscillation core of the first low-frequency oscillator 100 and the oscillation core of the second low-frequency oscillator); LC is the third-loop inductance (referring to the first inductor LC1, the second inductor LC2, the third inductor LC3 or the fourth inductor LC4); IC1 / IC2 are the current directions on the third-loop inductance.

[0084] Figure 3 Figure a is a schematic diagram of the working state of the low-frequency even mode. Figure 3 Figure b is a schematic diagram of the working state of the low-frequency odd mode. When oscillating in the high-frequency even mode, the oscillation directions of the corresponding sides of the two oscillation cores can be in phase, so the currents Icore1 and Icore2 of the oscillation cores are also in phase, so that the current IC1 induced by the magnetic coupling of the third-circle inductor of Icore1 is counterclockwise, and the current IC1 induced by the magnetic coupling of the third-circle inductor of Icore2 is clockwise, which makes the induced currents IC1 and IC2 cancel each other, and no induced current is generated in the third-circle inductor, so it will not affect the oscillation circuits of Core 1 and Core 2. Figure 3 As shown in a. In high-frequency odd-mode oscillation, the oscillation directions of the corresponding sides of the two oscillation cores can be reversed, so the currents Icore1 and Icore2 of the oscillation cores are also reversed, so that the current IC1 induced by the third-circle inductor of Icore1 through magnetic coupling is counterclockwise, and the current IC1 induced by the third-circle inductor of Icore2 through magnetic coupling is also counterclockwise, which makes the induced currents IC1 and IC2 in phase, and an induced current will be generated in the third-circle inductor. This current is opposite to Icore1 and Icore2, and the inductance values ​​of Core 1 and Core 2 are equivalently reduced through magnetic coupling, thereby increasing the oscillation frequency, as shown in FIG. Figure 3 As shown in b.

[0085] When the odd-even mode switch control module 500 controls the first high-frequency oscillator 300 and the second high-frequency oscillator 400 to work, the first low-frequency oscillator 100 and the second low-frequency oscillator 200 do not work, and the voltage-controlled oscillator oscillates at a high frequency. The odd-even mode switch control module 500 can also change the current direction of the first high-frequency oscillator 300 and the second high-frequency oscillator 400 so that the voltage-controlled oscillator can work in an even mode or an odd mode. When the voltage-controlled oscillator works in a high-frequency even mode, the tuning range is 25.8 GHz-31.5 GHz, and when the voltage-controlled oscillator works in a high-frequency even mode, the tuning range is 29.0 GHz-36.8 GHz. When the odd-even mode switch control module controls the first low-frequency oscillator 100 and the second low-frequency oscillator 200 to work, the first high-frequency oscillator 300 and the second high-frequency oscillator 400 do not work, and the voltage-controlled oscillator works at a low frequency. The odd-even mode switch control module 500 can also change the current direction of the first low-frequency oscillator 100 and the second low-frequency oscillator 200 so that the voltage-controlled oscillator can work in an even mode or an odd mode. When the voltage-controlled oscillator works in a low-frequency even mode, its even mode tuning range is 18.0 GHz to 22.3 GHz, and when the voltage-controlled oscillator works in a low-frequency odd mode, its odd mode tuning range is 20.6 GHz to 26.0 GHz, thereby achieving continuous frequency tuning from 18.0 GHz to 36.8 GHz, such as Figure 5 shown.

[0086] It can be seen that the present invention can control the first low-frequency oscillator and the second low-frequency oscillator to work in a low-frequency even mode or a low-frequency odd mode through the odd-even mode switch control module. When the odd-even mode switch control module controls the voltage-controlled oscillator to be in a low-frequency working mode or a high-frequency working mode, the first inductor, the second inductor, the third inductor, and the fourth inductor can be changed by changing the current direction of the first low-frequency oscillator and the second low-frequency oscillator and the current direction of the first high-frequency oscillator and the second high-frequency oscillator, so that the first inductor, the second inductor, the third inductor, and the fourth inductor have two different magnetic coupling modes for the first low-frequency oscillator, the second low-frequency oscillator, the first high-frequency oscillator, and the second high-frequency oscillator, thereby realizing two oscillation modes of even mode and odd mode, and finally realizing four oscillation modes of odd mode and even mode oscillating at a lower frequency and odd mode and even mode oscillating at a higher frequency. In this way, the present invention realizes continuous tuning of four oscillation modes by inductive coupling, and can improve the phase noise performance of the voltage-controlled oscillator compared with the capacitor array coupling while expanding the tuning range of the voltage-controlled oscillator.

[0087] In some embodiments, Figure 1 and Figure 4As shown, the odd-even mode switch control module 500 includes: a first low-frequency even mode switch SWLE1, a second low-frequency even mode switch SWLE2, a first low-frequency odd mode switch SWLO1, a second low-frequency odd mode switch SWLO2, a first high-frequency even mode switch SWHE1, a second high-frequency even mode switch SWHE2, a first high-frequency odd mode switch SWHO1 and a second high-frequency odd mode switch SWHO2. Wherein, the first low-frequency even-mode switch SWLE1 is connected between the first low-frequency oscillator 100 and the second low-frequency oscillator 200; the second low-frequency even-mode switch SWLE2 is connected between the first low-frequency oscillator 100 and the second low-frequency oscillator 200; the first low-frequency odd-mode switch SWLO1 is connected between the first low-frequency oscillator 100 and the second low-frequency oscillator 200; the second low-frequency odd-mode switch SWLO2 is connected between the first low-frequency oscillator 100 and the second low-frequency oscillator 200; the first high-frequency even-mode switch SWHE1 is connected between the first high-frequency oscillator 300 and the second high-frequency oscillator 400; the second high-frequency even-mode switch SWHE2 is connected between the first high-frequency oscillator 300 and the second high-frequency oscillator 400; the first high-frequency odd-mode switch SWHO1 is connected between the first high-frequency oscillator 300 and the second high-frequency oscillator 400; the second high-frequency odd-mode switch SWHO2 is connected between the first high-frequency oscillator 300 and the second high-frequency oscillator 400.

[0088] In this embodiment, when the first low-frequency even mode switch and the second low-frequency even mode switch are closed, the first low-frequency odd mode switch and the second low-frequency odd mode switch are opened, and the first oscillator and the second oscillator are working, and the first high-frequency oscillator and the second high-frequency oscillator are not working, the voltage-controlled oscillator is in the low-frequency even mode. When the first low-frequency even mode switch and the second low-frequency even mode switch are opened, the first low-frequency odd mode switch and the second low-frequency odd mode switch are closed, the first oscillator and the second oscillator are working, and the first high-frequency oscillator and the second high-frequency oscillator are not working, the voltage-controlled oscillator is in the low-frequency mode.

[0089] When the first high-frequency even mode switch is disconnected from the second high-frequency odd mode switch, the first high-frequency even mode switch is closed with the second high-frequency even mode switch, and the first oscillator and the second oscillator are not working, and the third oscillator and the fourth oscillator are working, the voltage-controlled oscillator is in the high-frequency even mode. When the first high-frequency even mode switch is closed with the second high-frequency odd mode switch, the first high-frequency even mode switch is disconnected from the second high-frequency even mode switch, and the first oscillator and the second oscillator are not working, and the third oscillator and the fourth oscillator are working, the voltage-controlled oscillator is in the high-frequency odd mode. The odd-even mode switch control module provided by the present invention has a simple structure and reduces the complexity of the voltage-controlled oscillator.

[0090] In some embodiments, Figure 1 and Figure 4 As shown, the first low frequency oscillator 100 includes: a first transistor M1, a second transistor M2, a fifth inductor LL1, a sixth inductor LL2, a first capacitor array CL1 and a second capacitor array CVL1. Among them, the gate of the first transistor M1 is connected to the drain of the second transistor M2, the drain of the first transistor M1 is respectively connected to the gate of the second transistor M2 and one end of the fifth inductor LL1, the source of the first transistor M1 is connected to the source of the second transistor M2; the drain of the second transistor M2 is also connected to one end of the sixth inductor LL2; the other end of the fifth inductor LL1 is respectively connected to the low-frequency power supply terminal VDD_L and the first low-frequency even mode switch SWLE1 and the first low-frequency odd mode switch SWLO1; the other end of the sixth inductor LL2 is respectively connected to the low-frequency power supply terminal VDD_L and the second low-frequency even mode switch SWLE2 and the second low-frequency odd mode switch SWLO2; one end of the first capacitor array CL1 is connected to one end of the fifth inductor LL1, and the other end of the first capacitor array CL1 is connected to one end of the sixth inductor LL2; the second capacitor array CVL1 is connected in parallel with the first capacitor array CL1.

[0091] Further, the second low-frequency oscillator 200 includes: a third transistor M3, a fourth transistor M4, a seventh inductor LL3, an eighth inductor LL4, a third capacitor array CL2 and a fourth capacitor array CVL2. The drain of the third transistor M3 is connected to the gate of the fourth transistor M4 and one end of the seventh inductor LL3, the gate of the third transistor M3 is connected to the drain of the fourth transistor M4, the source of the third transistor M3 is connected to the source of the fourth transistor M4; the drain of the fourth transistor M4 is also connected to one end of the eighth inductor LL4; the other end of the seventh inductor LL3 is connected to the first low-frequency even-mode switch SWLE1 and the second low-frequency odd-mode switch SWLO2; the other end of the eighth inductor LL4 is connected to the first low-frequency odd-mode switch SWLO1 and the second low-frequency even-mode switch SWLE2.

[0092] In some embodiments, Figure 1 and Figure 4 As shown, the first high frequency oscillator 300 includes: a fourth transistor M4, a fifth transistor M5, a ninth inductor LH1, a tenth inductor LH2, a fifth capacitor array CH1 and a sixth capacitor array CVH1. The gate of the fourth transistor M4 is connected to the drain of the fifth transistor M5, the drain of the fourth transistor M4 is respectively connected to the gate of the fifth transistor and one end of the ninth inductor, and the source of the fourth transistor is connected to the source of the fifth transistor M5; the drain of the fifth transistor M5 is also connected to one end of the tenth inductor LH2; the other end of the ninth inductor LH1 is respectively connected to the high-frequency power supply terminal VDD_H, the first high-frequency even-mode switch SWHE1, and the first high-frequency odd-mode switch SWHO1; the other end of the tenth inductor LH2 is respectively connected to the high-frequency power supply terminal VDD_H, the second high-frequency even-mode switch SWHE2, and the second high-frequency odd-mode switch SWHO2; one end of the fifth capacitor array CH1 is connected to one end of the ninth inductor LH1, and the other end of the fifth capacitor array CH1 is connected to one end of the tenth inductor LH2; the sixth capacitor array CVH1 is connected in parallel with the fifth capacitor array CH1.

[0093] Furthermore, the second high frequency oscillator 400 includes: a seventh transistor M7, an eighth transistor M8, an eleventh inductor LH3, a twelfth inductor LH4, a seventh capacitor array CH2 and an eighth capacitor array CVH2. The gate of the seventh transistor M7 is connected to the drain of the eighth transistor M8, the drain of the seventh transistor M7 is respectively connected to the gate of the eighth transistor M8 and one end of the eleventh inductor LH3, the source of the seventh transistor M7 is connected to the source of the eighth transistor M8; the drain of the eighth transistor M8 is also connected to one end of the twelfth inductor LH4; the other end of the eleventh inductor LH3 is respectively connected to the first high-frequency even mode switch SWHW1 and the second high-frequency odd mode switch SWHO2; the other end of the twelfth inductor LH4 is respectively connected to the second high-frequency even mode switch SWHE2 and the first high-frequency odd mode switch SWHO1; one end of the seventh capacitor array CH2 is connected to one end of the eleventh inductor LH3, the other end of the eighth capacitor array CVH2 is connected to one end of the twelfth inductor LH4; the eighth capacitor array CVH2 is connected in parallel with the seventh capacitor array CH2.

[0094] Specifically, the first transistor M1, the second transistor M2, the fifth inductor LL1, the sixth inductor LL2, the first capacitor array CL1 and the second capacitor array CVL1, and the third transistor M3, the fourth transistor M4, the seventh inductor LL3, the eighth inductor LL4, the third capacitor array CL2 and the fourth capacitor array CVL2 constitute a dual-core oscillator in a low-frequency mode, the first low-frequency even mode switch and the second low-frequency even mode switch are low-frequency even mode switches, and the first low-frequency odd mode switch and the second low-frequency odd mode switch are low-frequency odd mode switches. The fourth transistor M4, the fifth transistor M5, the ninth inductor LH1, the tenth inductor LH2, the fifth capacitor array CH1 and the sixth capacitor array CVH1 and the seventh transistor M7, the eighth transistor M8, the eleventh inductor LH3, the twelfth inductor LH4, the seventh capacitor array CH2 and the eighth capacitor array CVH2 form a high-frequency mode dual-core oscillator, the first high-frequency even mode switch and the second high-frequency even mode switch are high-frequency even mode switches, and the first high-frequency odd mode switch and the second high-frequency odd mode switch are high-frequency odd mode switches.

[0095] The coupling coefficient between the first inductor LC1 and the fifth inductor LL1 is KCL1, the coupling coefficient between the first inductor LC1 and the ninth inductor LH1 is KCH1, and the coupling coefficient between the fifth inductor and the ninth inductor is KLH1; the coupling coefficient between the second inductor LC2 and the sixth inductor LL2 is KCL2, the coupling coefficient between the second inductor LC2 and the tenth inductor LH2 is KCH2, and the coupling coefficient between the sixth inductor LL2 and the tenth inductor LH2 is KLH2; The coupling coefficient between the third inductor LC3 and the seventh inductor LL3 is KCL3, the coupling coefficient between the third inductor LC3 and the eleventh inductor LH3 is KCH3, and the coupling coefficient between the seventh inductor LL3 and the eleventh inductor is KLH3; the coupling coefficient between the third inductor LC3 and the eighth inductor LL4 is KCL4, the coupling coefficient between the fourth inductor LC4 and the twelfth inductor LH4 is KCH4, and the coupling coefficient between the eighth inductor LL4 and the twelfth inductor LH4 is KLH4. It should be noted that the frequency difference between the low-frequency peak and the high-frequency peak of the transformer-based single-port oscillator is related to its coupling coefficient KLH. The larger the coupling coefficient KLH, the farther the two peaks are from each other, and the smaller the coupling coefficient KLH, the closer they are.

[0096] When the voltage-controlled oscillator operates in the low-frequency even mode, the first low-frequency even mode switch SWLE1 and the second low-frequency even mode switch SWLE2 are closed, the first low-frequency odd mode switch SWLO1 and the second low-frequency odd mode switch SWLO2 are disconnected, the low-frequency power supply terminal is set to the supply voltage, and the high-frequency power supply terminal is set to 0 voltage. The first capacitor array CL1 is a 4-bit capacitor array, which is kept fully disconnected in the 0000 state. The second capacitor array is a transistor variable capacitor array, and its voltage VC is 1 to keep the capacitance minimum. Since the high-frequency power supply terminal voltage is 0, the fifth transistor M5, the sixth transistor M6, the seventh transistor M7, and the eighth transistor M8 do not work. At this time, the working states of the two oscillation cores (the first low-frequency oscillator and the second low-frequency oscillator) and the third coil inductor are as follows: Figure 3 Even modes in . Figure 3 As shown, in the low-frequency even mode, the closure of the first low-frequency even mode switch and the second low-frequency even mode switch makes the oscillation directions of the corresponding sides of the two oscillation cores in phase, and no induced current will be generated in the third circle inductor, thereby not affecting the oscillation circuits of the first oscillator and the second oscillator.

[0097] When the voltage controlled oscillator works in the low frequency odd mode, the first low frequency odd mode switch SWLO1 and the second low frequency odd mode switch SWLO2 are closed, the first low frequency even mode switch SWLE1 and the second low frequency even mode switch SWLE2 are disconnected, the low frequency power supply terminal provides the power supply voltage, the high frequency power supply terminal is 0 voltage, the first capacitor array CL1 is a 4-bit capacitor array, which is kept fully disconnected in the 0000 state, and the second capacitor array CVL1 is a transistor variable capacitor array, whose voltage VC is 1 to keep the capacitance minimum. Since the voltage at the high frequency power supply terminal is 0, the fifth transistor M5, the sixth transistor M6, the seventh transistor M7, and the eighth transistor M8 do not work. At this time, the working states of the two oscillation cores (the first low frequency oscillator and the second low frequency oscillator) and the third coil inductor are as follows: Figure 3 In the odd mode. In the low-frequency odd mode working state, the closing of the first low-frequency odd mode switch SWLO1 and the second low-frequency odd mode switch SWLO2 makes the oscillation directions of the corresponding sides of the first low-frequency oscillator 100 and the second low-frequency oscillator 200 opposite, so the currents Icore1 and Icore2 of the oscillation core are also in reverse phase, and an induced current will be generated in the third coil inductor. The induced current is opposite to both Icore1 and Icore2, and the inductance values ​​in Core1 and Core2 are equivalently reduced through magnetic coupling, thereby increasing the oscillation frequency. By selecting a suitable 4-bit capacitor array CL1, a transistor variable capacitor CVL1, and a coupling coefficient KCL1 between the fifth inductor LL1 and the first inductor LC1, 32 continuous tuning curves of odd mode and even mode in low-frequency mode can be realized.

[0098] The working principle of the odd-even mode switching working in the high-frequency mode is the same as the working principle of the odd-even mode switching working in the low-frequency mode, except that when working in the high-frequency mode, the low-frequency power supply end is set to 0 voltage, the high-frequency power supply end is set to provide a power supply voltage, and the first transistor M1, the second transistor M2, the third transistor M3 and the fourth transistor M4 will not work. The first capacitor array CL1 and the third capacitor array CL2 of the 4-bit capacitor array are 1111 to maintain full access, and the voltage VC of the transistor variable capacitor of the second capacitor array CVL1 and the fourth capacitor array CVL2 is 0 to maintain the maximum capacitance, thereby avoiding oscillation mode mixing. In the high-frequency mode, when the first high-frequency even mode switch is disconnected from the second high-frequency odd mode switch, the first high-frequency even mode switch is closed with the second high-frequency even mode switch, and the voltage-controlled oscillator is in the high-frequency even mode. When the first high-frequency even mode switch is closed with the second high-frequency odd mode switch, the first high-frequency even mode switch is disconnected from the second high-frequency even mode switch, and the voltage-controlled oscillator is in the high-frequency odd mode. Similarly, by selecting appropriate 4-bit capacitor arrays CH1, CH2, transistor variable capacitors CVH1, CVH2, and the coupling coefficient KCH1 between the ninth inductor LH1 and the first inductor LC1, 32 tuning curves of odd mode and even mode continuity in high-frequency mode can be realized. Among them, by selecting the appropriate coupling coefficient KLH1 between the inductors LL1 and LH1 of the transformer, selecting the appropriate 4-bit capacitor array and transistor variable capacitor array in the low-frequency mode and the high-frequency mode, the tuning curves of the low-frequency mode and the high-frequency mode can be made continuous, so that a broadband four-mode voltage-controlled oscillator with 64 tuning curves can be obtained, and its tuning curves are as follows: Figure 5 shown.

[0099] In some embodiments, the millimeter wave voltage-controlled oscillator also includes: a first common-mode secondary resonant bandwidth extension module 600 and a second common-mode secondary resonant bandwidth extension module 700; the first common-mode secondary resonant bandwidth extension module 600 is respectively connected to the first low-frequency oscillator 100 and the second low-frequency oscillator 200, and the first common-mode secondary resonant bandwidth extension module 600 is used to improve the phase noise performance in the low-frequency mode; the second common-mode secondary resonant bandwidth extension module 700 is respectively connected to the first high-frequency oscillator 300 and the second high-frequency oscillator 400, and the second common-mode secondary resonant bandwidth extension module 700 is used to improve the phase noise performance in the high-frequency mode.

[0100] Specifically, the first common-mode secondary resonant bandwidth extension module 600 includes: a thirteenth inductor LS1, a fourteenth inductor LS2, a first capacitor CS1 and a second capacitor CP1. One end of the thirteenth inductor LS1 is connected to the first low-frequency oscillator 100 and the second low-frequency oscillator 200 respectively, and the other end of the thirteenth inductor LS1 is grounded; one end of the fourteenth inductor LS2 is connected to one end of the first capacitor CS1, and the other end of the fourteenth inductor LS2 is connected to one end of the second capacitor CP1; the thirteenth inductor LS1 is coupled with the fourteenth inductor LS2; the other end of the first capacitor CS1 is grounded; and the other end of the second capacitor CP1 is grounded.

[0101] Further, the second common-mode secondary resonance bandwidth extension module 700 includes: a fifteenth inductor LS3, a sixteenth inductor LS4, a third capacitor CS2 and a fourth capacitor CP2. One end of the fifteenth inductor LS3 is connected to the first high-frequency oscillator 300 and the second high-frequency oscillator 400 respectively, and the other end of the fifteenth inductor LS3 is grounded; one end of the sixteenth inductor LS4 is connected to one end of the third capacitor CS2, and the other end of the sixteenth inductor LS4 is connected to one end of the fourth capacitor CP2; the fifteenth inductor LS3 is coupled with the sixteenth inductor LS4; the other end of the third capacitor CS2 is grounded; and the other end of the fourth capacitor CP2 is grounded.

[0102] A loop of tail common-mode secondary resonance bandwidth extension technology is added to the tail of the oscillation core. The tail common-mode secondary resonance can improve phase noise performance by preventing the cross-coupled transistor from entering the triode region and by suppressing the flicker noise up-conversion process. Figure 6 From the Z parameter frequency response diagram, it can be seen that the band circuit can form an impedance loop at the tail of the oscillator that has a peak bandwidth expansion effect at the secondary resonant frequency. The bandwidth expansion effect can make it unnecessary to adjust the tail capacitor to match the secondary resonant frequency with the oscillation frequency when the oscillation frequency changes, eliminating the need for an additional capacitor array.

[0103] In some embodiments, Figure 7 As shown, the present invention also provides an oscillation mode control method based on the above-mentioned millimeter wave voltage-controlled oscillator, which comprises the steps of:

[0104] S100. When the voltage-controlled oscillator is required to be in a low-frequency oscillation mode, the first low-frequency oscillator and the second low-frequency oscillator are controlled to work, the first high-frequency oscillator and the second high-frequency oscillator are controlled not to work, and the current directions of the first low-frequency oscillator and the second low-frequency oscillator are changed through the odd-even mode switch control module, so that the voltage-controlled oscillator is in a low-frequency even mode or a low-frequency odd mode; the specific details are as described in an embodiment of a millimeter-wave voltage-controlled oscillator, which will not be repeated here.

[0105] S200: When the voltage-controlled oscillator is required to be in high-frequency oscillation mode, the first high-frequency oscillator and the second high-frequency oscillator are controlled to work, the first low-frequency oscillator and the second low-frequency oscillator are controlled not to work, and the current directions of the first high-frequency oscillator and the second high-frequency oscillator are changed by the odd-even mode switch control module, so that the voltage-controlled oscillator is in high-frequency even mode or high-frequency odd mode. The details are as described in an embodiment of a millimeter-wave voltage-controlled oscillator, which will not be repeated here.

[0106] In summary, the millimeter wave voltage-controlled oscillator and the oscillation mode control method thereof provided by the present invention have the following beneficial effects:

[0107] A broadband voltage-controlled oscillator with four modes is realized by combining a transformer-based single-port oscillator with two oscillation peaks and a third-turn inductor to realize odd-even mode oscillation switching. This can extend the tuning range of the voltage-controlled oscillator and improve the phase noise performance of the voltage-controlled oscillator compared to capacitor array coupling.

[0108] By adding the tail common mode secondary resonance bandwidth extension technology, the phase noise performance of the oscillator is improved;

[0109] The odd-even mode switch control module has a simple structure, reduces the complexity of the voltage-controlled oscillator, and has a lower cost.

[0110] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A millimeter wave voltage-controlled oscillator, characterized in that: include: A first low-frequency oscillator, a second low-frequency oscillator, a first high-frequency oscillator, a second high-frequency oscillator, a first inductor, a second inductor, a third inductor, a fourth inductor and an odd-even mode switch control module; The odd-even mode switch control module is connected between the first low frequency oscillator and the second low frequency oscillator and between the first high frequency oscillator and the second high frequency oscillator; The first inductor and the second inductor are coupled to the first low-frequency oscillator and the first high-frequency oscillator respectively; the third inductor and the fourth inductor are coupled to the second low-frequency oscillator and the second high-frequency oscillator respectively; The odd-even mode switch control module is used to control the first low frequency oscillator and the second low frequency oscillator to operate in a low frequency even mode or a low frequency odd mode, and is used to control the first high frequency oscillator and the second high frequency oscillator to operate in a high frequency even mode and a high frequency odd mode.

2. The millimeter wave voltage-controlled oscillator according to claim 1, characterized in that: The odd-even mode switch control module includes: a first low-frequency even mode switch, a second low-frequency even mode switch, a first low-frequency odd mode switch, a second low-frequency odd mode switch, a first high-frequency even mode switch, a second high-frequency even mode switch, a first high-frequency odd mode switch and a second high-frequency odd mode switch; wherein, The first low-frequency even-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; the second low-frequency even-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; The first low-frequency odd-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; the second low-frequency odd-mode switch is connected between the first low-frequency oscillator and the second low-frequency oscillator; The first high-frequency even-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator; the second high-frequency even-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator; The first high-frequency odd-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator; the second high-frequency odd-mode switch is connected between the first high-frequency oscillator and the second high-frequency oscillator.

3. The millimeter wave voltage-controlled oscillator according to claim 2, characterized in that: The first low frequency oscillator comprises: a first transistor, a second transistor, a fifth inductor, a sixth inductor, a first capacitor array and a second capacitor array; wherein, The gate of the first transistor is connected to the drain of the second transistor, the drain of the first transistor is connected to the gate of the second transistor and one end of the fifth inductor respectively, and the source of the first transistor is connected to the source of the second transistor; The drain of the second transistor is also connected to one end of the sixth inductor; The other end of the fifth inductor is respectively connected to the low-frequency power supply end and the first low-frequency even-mode switch and the first low-frequency odd-mode switch; The other end of the sixth inductor is connected to the low-frequency power supply end and the second low-frequency even-mode switch and the second low-frequency odd-mode switch respectively; One end of the first capacitor array is connected to one end of the fifth inductor, and the other end of the first capacitor array is connected to one end of the sixth inductor; the second capacitor array is connected in parallel with the first capacitor array.

4. The millimeter wave voltage-controlled oscillator according to claim 2, characterized in that: The second low frequency oscillator comprises: a third transistor, a fourth transistor, a seventh inductor, an eighth inductor, a third capacitor array and a fourth capacitor array; wherein, The drain of the third transistor is connected to the gate of the fourth transistor and one end of the seventh inductor respectively, the gate of the third transistor is connected to the drain of the fourth transistor, and the source of the third transistor is connected to the source of the fourth transistor; The drain of the fourth transistor is also connected to one end of the eighth inductor; The other end of the seventh inductor is connected to the first low-frequency even-mode switch and the second low-frequency odd-mode switch respectively; The other end of the eighth inductor is connected to the first low-frequency odd-mode switch and the second low-frequency even-mode switch respectively.

5. The millimeter wave voltage-controlled oscillator according to claim 2, characterized in that: The first high frequency oscillator includes: a fourth transistor, a fifth transistor, a ninth inductor, a tenth inductor, a fifth capacitor array and a sixth capacitor array; wherein, The gate of the fourth transistor is connected to the drain of the fifth transistor, the drain of the fourth transistor is respectively connected to the gate of the fifth transistor and one end of the ninth inductor, and the source of the fourth transistor is connected to the source of the fifth transistor; The drain of the fifth transistor is also connected to one end of the tenth inductor; The other end of the ninth inductor is respectively connected to the high-frequency power supply end, the first high-frequency even-mode switch, and the first high-frequency odd-mode switch; The other end of the tenth inductor is respectively connected to the high-frequency power supply end, the second high-frequency even-mode switch and the second high-frequency odd-mode switch; One end of the fifth capacitor array is connected to one end of the ninth inductor, and the other end of the fifth capacitor array is connected to one end of the tenth inductor; the sixth capacitor array is connected in parallel with the fifth capacitor array.

6. The millimeter wave voltage-controlled oscillator according to claim 2, characterized in that: The second high frequency oscillator includes: a seventh transistor, an eighth transistor, an eleventh inductor, a twelfth inductor, a seventh capacitor array and an eighth capacitor array; wherein, The gate of the seventh transistor is connected to the drain of the eighth transistor, the drain of the seventh transistor is respectively connected to the gate of the eighth transistor and one end of the eleventh inductor, and the source of the seventh transistor is connected to the source of the eighth transistor; The drain of the eighth transistor is also connected to one end of the twelfth inductor; The other end of the eleventh inductor is respectively connected to the first high-frequency even-mode switch and the second high-frequency odd-mode switch; The other end of the twelfth inductor is respectively connected to the second high-frequency even-mode switch and the first high-frequency odd-mode switch; One end of the seventh capacitor array is connected to one end of the eleventh inductor, and the other end of the eighth capacitor array is connected to one end of the twelfth inductor; the eighth capacitor array is connected in parallel with the seventh capacitor array.

7. The millimeter wave voltage-controlled oscillator according to claim 1, characterized in that: Also includes: A first common-mode secondary resonance bandwidth extension module and a second common-mode secondary resonance bandwidth extension module; The first common-mode secondary resonance bandwidth extension module is connected to the first low-frequency oscillator and the second low-frequency oscillator respectively, and the first common-mode secondary resonance bandwidth extension module is used to improve the phase noise performance in the low-frequency mode; The second common-mode secondary resonance bandwidth extension module is connected to the first high-frequency oscillator and the second high-frequency oscillator respectively, and the second common-mode secondary resonance bandwidth extension module is used to improve the phase noise performance in the high-frequency mode.

8. The millimeter wave voltage-controlled oscillator according to claim 7, characterized in that: The first common-mode secondary resonance bandwidth extension module includes: a thirteenth inductor, a fourteenth inductor, a first capacitor and a second capacitor; wherein, One end of the thirteenth inductor is connected to the first low-frequency oscillator and the second low-frequency oscillator respectively, and the other end of the thirteenth inductor is grounded; One end of the fourteenth inductor is connected to one end of the first capacitor, and the other end of the fourteenth inductor is connected to one end of the second capacitor; The thirteenth inductor is coupled to the fourteenth inductor; The other end of the first capacitor is grounded; the other end of the second capacitor is grounded.

9. The millimeter wave voltage-controlled oscillator according to claim 7, characterized in that: The second common-mode secondary resonance bandwidth extension module includes: a fifteenth inductor, a sixteenth inductor, a third capacitor and a fourth capacitor; wherein, One end of the fifteenth inductor is connected to the first high-frequency oscillator and the second high-frequency oscillator respectively, and the other end of the fifteenth inductor is grounded; One end of the sixteenth inductor is connected to one end of the third capacitor, and the other end of the sixteenth inductor is connected to one end of the fourth capacitor; The fifteenth inductor is coupled to the sixteenth inductor; The other end of the third capacitor is grounded; the other end of the fourth capacitor is grounded.

10. An oscillation mode control method of a millimeter wave voltage-controlled oscillator according to any one of claims 1 to 9, characterized in that: include: When the voltage-controlled oscillator is required to be in a low-frequency oscillation mode, the first low-frequency oscillator and the second low-frequency oscillator are controlled to work, the first high-frequency oscillator and the second high-frequency oscillator are controlled not to work, and the current directions of the first low-frequency oscillator and the second low-frequency oscillator are changed by the odd-even mode switch control module, so that the voltage-controlled oscillator is in a low-frequency even mode or a low-frequency odd mode; When the voltage-controlled oscillator is required to be in a high-frequency oscillation mode, the first high-frequency oscillator and the second high-frequency oscillator are controlled to work, the first low-frequency oscillator and the second low-frequency oscillator are controlled not to work, and the current directions of the first high-frequency oscillator and the second high-frequency oscillator are changed through the odd-even mode switch control module, so that the voltage-controlled oscillator is in a high-frequency even mode or a high-frequency odd mode.

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