A multi-core voltage controlled oscillator and a communication transceiver

Abstract

The embodiment of the present application provides a multi-core voltage-controlled oscillator and a communication transceiver, at least two voltage-controlled oscillator cores are stacked in the voltage-controlled oscillator. The embodiment of the present application reduces the phase noise of the voltage-controlled oscillator, reduces the overall power consumption of the voltage-controlled oscillator, has a multi-oscillation mode to expand the tuning range of the voltage-controlled oscillator, improves the system reliability, and significantly improves the overall performance of the voltage-controlled oscillator.

Description

Technical Field

[0001] This invention relates to the field of millimeter-wave radio frequency integrated circuit technology, specifically to a multi-core voltage-controlled oscillator and a communication transceiver. Background Technology

[0002] For communication transceivers, the voltage-controlled oscillator (VCO) is an essential circuit unit. With the development of 5G communication systems in recent years, the requirements for the spectral purity of millimeter-wave local oscillator signals have become increasingly stringent. This means that low phase noise is crucial for high-order modulation targeting high data rates. Simultaneously, 5G communication systems also possess multi-band characteristics, thus requiring the millimeter-wave local oscillator signal to have a sufficiently wide tuning range to support these different frequency bands. Finally, equally important are the power consumption and reliability of the VCO; low power consumption and high reliability have a critical impact on the overall system application.

[0003] On the one hand, to achieve low phase noise, a common approach in recent research is to use multi-core voltage-controlled oscillator (VCO) structures. While existing multi-core approaches reduce phase noise by increasing the number of cores, this leads to significant power consumption and increased chip heat generation, thus deteriorating chip reliability and performance. Simultaneously, existing multi-core approaches often employ non-standard power supply voltages. When multi-core VCOs using non-standard power supply voltages are applied to practical systems, additional tail current source transistors or low dropout regulators (LDOs) are needed to adapt to the standard power supply voltage used by the actual system, preventing reliability issues due to excessive voltage. However, these additional circuit components introduce additional power consumption and non-ideal effects, thereby reducing the overall performance of the VCO when applied to practical systems.

[0004] On the other hand, to achieve a wide tuning range, a common approach in recent research is to use multiple oscillation modes. Multiple different oscillation modes have different resonant frequencies, thus widening the overall tuning range of the voltage-controlled oscillator (VCO). Existing methods for implementing multiple oscillation modes include different core on / off states or more complex resonant cavity inductor routing. The problem with these multi-mode approaches is that they all introduce a considerable degree of parasitic effects, which degrade the overall performance of the VCO. Summary of the Invention

[0005] To address the shortcomings of existing technologies, embodiments of the present invention provide a multi-core voltage-controlled oscillator, including multiple voltage-controlled oscillator cores and a synchronization circuit.

[0006] The voltage-controlled oscillator core includes a resonant cavity and an active component. The resonant cavity and the active component are differentially connected. A differential oscillation signal exists at the differential connection node.

[0007] The synchronization circuit connects the differential oscillation signal of each voltage-controlled oscillator core to achieve synchronization of the oscillation signals of each voltage-controlled oscillator core and to enable selection of the oscillation mode.

[0008] In this configuration, following the direction of DC current flow, the DC current outflow node of the active portion of the preceding voltage-controlled oscillator (VCO) core is connected to the DC current inflow node of the resonant cavity of the next VCO core, thus achieving the stacking of the VCO cores. The stacked VCO cores achieve current multiplexing, and the resonant cavities of the stacked VCO cores are mutually coupled to achieve multiple oscillation modes.

[0009] According to an embodiment of the present invention, a multi-core voltage-controlled oscillator is provided, wherein the multiple voltage-controlled oscillator cores are connected to a power supply VDD; the power consumption of the multi-core voltage-controlled oscillator is expressed as follows:

[0010] P = V DD ×I

[0011] Where P represents the power consumption of the multi-core voltage-controlled oscillator, and I represents the current flowing through the stacked voltage-controlled oscillator cores.

[0012] The multi-core voltage-controlled oscillator and communication transceiver provided in this invention reduce the phase noise of the voltage-controlled oscillator, reduce the overall power consumption of the voltage-controlled oscillator, have multiple oscillation modes to expand the tuning range of the voltage-controlled oscillator, and improve system reliability, thus significantly improving the overall performance of the voltage-controlled oscillator. Attached Figure Description

[0013] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is one of the structural schematic diagrams of existing multi-core voltage-controlled oscillators;

[0015] Figure 2 This is one of the structural schematic diagrams of the multi-core voltage-controlled oscillator provided in the embodiments of the present invention;

[0016] Figure 3 This is the second schematic diagram of an existing multi-core voltage-controlled oscillator.

[0017] Figure 4 This is the second schematic diagram of the structure of the multi-core voltage-controlled oscillator provided in the embodiment of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0019] Figure 1 This is one of the structural schematic diagrams of existing multi-core voltage-controlled oscillators. For example... Figure 1 The multi-core voltage-controlled oscillator shown has independent cores and the following characteristics:

[0020] (1) Number of cores: This voltage-controlled oscillator has N cores;

[0021] (2) Oscillation Mode: This voltage-controlled oscillator has only one oscillation mode, that is, the N cores have only one oscillation polarity; the synchronization circuit connects the differential oscillation signal of each voltage-controlled oscillator core to realize the synchronization of the oscillation signals of each voltage-controlled oscillator core. This multi-core voltage-controlled oscillator only allows the existence of one oscillation mode, that is, only allows one synchronized oscillation polarity.

[0022] (3) Power consumption: Assuming that the current consumed by each voltage-controlled oscillator core is I and the power supply voltage is VDD, the overall power consumption of the voltage-controlled oscillator is N×VDD×I.

[0023] Figure 2 This is one of the structural schematic diagrams of the multi-core voltage-controlled oscillator provided in an embodiment of the present invention. For example... Figure 2 As shown, the multi-core voltage-controlled oscillator (VCO) includes multiple VCO cores 1 and a synchronization circuit 2. Each VCO core 1 includes a resonant cavity 10 and an active portion 20. The resonant cavity 10 and the active portion 20 are differentially connected. Differential oscillation signals exist at the differential connection nodes. The synchronization circuit 2 connects the differential oscillation signals of each VCO core 1, synchronizing the oscillation signals of each VCO core 1 and enabling the selection of oscillation modes. Specifically, according to the direction of DC current flow, the DC current outflow node of the active portion 20 of the previous VCO core 1 connects to the DC current inflow node of the resonant cavity 10 of the next VCO core 1, achieving stacking of the VCO cores 1. The stacked VCO cores 1 achieve current multiplexing, and the resonant cavities 10 of the stacked VCO cores 1 are coupled to each other to achieve multiple oscillation modes.

[0024] Figure 2 In the text, #1, #2...#3 represent serial numbers.

[0025] The multi-core voltage-controlled oscillator provided in this embodiment of the invention reduces phase noise through multiple voltage-controlled oscillator cores 1.

[0026] The multi-core voltage-controlled oscillator provided in this embodiment of the invention achieves current reuse through the stacked structure of the voltage-controlled oscillator core 1, greatly reducing the power consumption of the multi-core and solving the reliability problem in practical systems. Furthermore, by stacking, the standard power supply voltage VDD can be used directly without the need for additional tail current source transistors or low-dropout regulators (LDOs).

[0027] The multi-core voltage-controlled oscillator provided in this embodiment of the invention achieves multiple oscillation modes through mutual coupling (electromagnetic coupling) between the resonant cavities 10 of each voltage-controlled oscillator core 1. A synchronization circuit 2 connects the differential oscillation signal of each voltage-controlled oscillator core 1, thereby synchronizing the oscillation signals of each voltage-controlled oscillator core 1 and enabling the selection of oscillation modes.

[0028] like Figure 2 As shown, the multi-core voltage-controlled oscillator provided in this embodiment of the invention achieves multiple modes through coupling and has a multi-core stacked structure, which can be called a coupling-based multi-core stacked voltage-controlled oscillator, and has the following characteristics:

[0029] (1) Number of cores: The voltage-controlled oscillator has N cores (voltage-controlled oscillator cores), but the N cores are stacked together to achieve current reuse.

[0030] (2) Oscillation mode: Since the resonant cavities 10 corresponding to the N cores are coupled to each other, the magnetic coupling can control the oscillation polarity of each core through the synchronization circuit 2. This is equivalent to changing the overall inductance value of the resonant cavity. Therefore, the voltage-controlled oscillator has multiple oscillation modes, and the oscillation mode can be selected through the synchronization circuit 2 of the voltage-controlled oscillator.

[0031] Synchronization circuit 2 connects the differential oscillation signal of each voltage-controlled oscillator core 1, thereby synchronizing the oscillation signals of each voltage-controlled oscillator core 1. Figure 1 The difference between the multi-core voltage-controlled oscillator shown is that, due to the fact that... Figure 2 In the coupled multi-core stacked voltage-controlled oscillator shown, there is coupling between the resonant cavities 10 of each voltage-controlled oscillator core 1, thus allowing for a variety of different oscillation modes.

[0032] The multi-mode operation implemented through coupling introduces virtually no additional parasitic effects. This is because, in each coupled multi-mode operation, all cores are operational, without affecting the on / off state of the active portion 20 of the voltage-controlled oscillator (VCO) core 1. Furthermore, the differential oscillation signals on both sides of the synchronization circuit 2 have the same polarity, and the synchronization circuit 2 exhibits no parasitic resistance or capacitance for the differential oscillation signals. Therefore, the overall performance of the VCO is not affected by the multi-mode operation, and mode selection is very simple, requiring only the synchronization circuit 2. It is worth noting that if multi-mode operation is not required, the synchronization circuit 2 can also control the VCO to operate in a single oscillation mode.

[0033] (3) Power consumption: Assuming that the current consumed by each voltage-controlled oscillator core is I and the power supply voltage is VDD, since the N cores achieve current reuse through stacking, the overall power consumption of the voltage-controlled oscillator is VDD×I, which greatly reduces the power consumption of multi-core.

[0034] The multi-core voltage-controlled oscillator provided in this embodiment of the invention achieves multiple modes through coupling and has a multi-core stacked structure: (1) the multi-mode mainly improves the tuning range of the voltage-controlled oscillator; (2) the multi-core mainly reduces the phase noise of the voltage-controlled oscillator; (3) the stacking multiplexes the current of the multiple cores of the voltage-controlled oscillator, reducing the power consumption of the voltage-controlled oscillator. Therefore, the overall voltage-controlled oscillator can have better FoM (Figure of Merit) and FoM. T (Figure of Merit with Tuning Range). Wherein, FoM and FoM T These are all comprehensive performance evaluation indicators for voltage-controlled oscillators.

[0035] The multi-core voltage-controlled oscillator provided in this embodiment of the invention reduces the phase noise of the voltage-controlled oscillator, reduces the overall power consumption of the voltage-controlled oscillator, has multiple oscillation modes to expand the tuning range of the voltage-controlled oscillator, and improves system reliability, thus significantly improving the overall performance of the voltage-controlled oscillator.

[0036] The following example, a dual-core voltage-controlled oscillator, illustrates the difference between existing voltage-controlled oscillator structures and the voltage-controlled oscillator structure provided by this invention.

[0037] Figure 3 This is the second schematic diagram of an existing multi-core voltage-controlled oscillator. (For example...) Figure 3As shown, the resonant cavity is an LC oscillator circuit, composed of a parallel inductor and an adjustable capacitor. The active part of the voltage-controlled oscillator (VCO) core uses cross-coupled transistors, including two field-effect transistors (FETs). The gate of each FET is cross-connected to the drain of the other FET, and the drain of each FET is connected to the resonant cavity. The center tap of the inductor in the resonant cavity is connected to the power supply VDD, and the sources of the two FETs in the cross-coupled circuit are grounded. The core circuits of each VCO are connected in the same way and are independent of each other. Figure 3 As shown, this existing multi-core voltage-controlled oscillator has the following characteristics:

[0038] (1) Number of cores: This voltage-controlled oscillator has two cores;

[0039] (2) Oscillation mode: This voltage-controlled oscillator has only one oscillation mode;

[0040] (3) Regarding power consumption, assume that the current consumed by each voltage-controlled oscillator core is I and the power supply voltage is V. DD Therefore, the overall power consumption of the voltage-controlled oscillator is 2×V. DD ×I.

[0041] Figure 4 This is a second schematic diagram of the structure of the multi-core voltage-controlled oscillator provided in an embodiment of the present invention. Figure 4 As shown, the resonant cavity is an LC oscillating circuit, composed of parallel inductors and adjustable capacitors. The active part of the voltage-controlled oscillator (VCO) core uses cross-coupled transistors, which include two field-effect transistors (FETs). The gate of each FET is cross-connected to the drain of the other FET, and the drain of each FET is connected to the resonant cavity. Following the current flow direction, the center tap of the inductor in the resonant cavity of VCO core #2 is connected to the power supply VDD. The sources of the two FETs in the cross-coupled section of VCO core #2 are connected to the center tap of the inductor in the resonant cavity of the second VCO core #1. The sources of the two FETs in VCO core #1 are grounded. The two VCO cores form a stacked structure, and their resonant cavities are mutually coupled. Figure 4 As shown, this multi-core voltage-controlled oscillator has the following characteristics:

[0042] (1) Number of cores: This voltage-controlled oscillator has two cores, but the two cores are stacked together to achieve current multiplexing;

[0043] (2) Oscillation mode: There is magnetic field coupling between the inductors of the two core resonant cavities, so there are two oscillation modes. The oscillation mode can be selected by the synchronization circuit.

[0044] (3) Power consumption: Assuming that the current consumed by each voltage-controlled oscillator core is I and the power supply voltage is VDD, since the two cores achieve current reuse through stacking, the overall power consumption of the voltage-controlled oscillator is VDD×I.

[0045] As can be seen, compared with the existing ordinary dual-core voltage-controlled oscillators, the coupled dual-core stacked voltage-controlled oscillators not only have the advantage of multi-core to reduce phase noise, but also realize multi-mode oscillation through coupling, thus widening the tuning range. At the same time, the stacking of the voltage-controlled oscillator cores realizes current reuse, reduces the total power consumption of the voltage-controlled oscillator, and solves the reliability problem in practical systems.

[0046] Alternatively, two transistors can be used to construct a cross-coupled transistor. The circuit connection method is similar to that of a cross-coupled transistor constructed using a field-effect transistor, and will not be elaborated here.

[0047] In addition, embodiments of the present invention provide a communication transceiver, including the multi-core voltage-controlled oscillator provided in any of the above embodiments of the present invention.

[0048] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0049] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-core voltage-controlled oscillator, characterized in that, Includes multiple voltage-controlled oscillator cores and synchronization circuits; The core of the voltage-controlled oscillator includes a resonant cavity and an active part; the resonant cavity and the active part are differentially connected to each other, and a differential oscillation signal exists at the differential connection node; The synchronization circuit connects the differential oscillation signal of each voltage-controlled oscillator core to achieve synchronization of the oscillation signals of each voltage-controlled oscillator core and to enable selection of the oscillation mode. In this configuration, according to the direction of DC current flow, the DC current outflow node of the active part of the previous voltage-controlled oscillator core is connected to the DC current inflow node of the resonant cavity of the next voltage-controlled oscillator core, thereby realizing the stacking of the voltage-controlled oscillator cores; the stacked multiple voltage-controlled oscillator cores achieve current reuse, and the resonant cavities of the stacked multiple voltage-controlled oscillator cores are mutually coupled to realize multiple oscillation modes.

2. The multi-core voltage-controlled oscillator according to claim 1, characterized in that, The multiple voltage-controlled oscillators are connected to the power supply VDD; the power consumption of the multi-core voltage-controlled oscillator is expressed as follows: P=V DD ×I Where P represents the power consumption of the multi-core voltage-controlled oscillator, and I represents the current flowing through the stacked voltage-controlled oscillator cores.

3. A communication transceiver, characterized in that, Includes any of the multi-core voltage-controlled oscillators described in claim 1 or 2.

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