A magnetically coupled high power radio frequency source integrated circuit
By integrating an active negative resistance generation module, a multi-coil magnetic coupling feedback module, and a digital frequency modulation module, the design solves the problems of high power consumption and large area in traditional RF transceivers, realizing a low-power, high-power RF frequency source and optimizing the phase noise and driving capability of the frequency source.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING FUAOXING ELECTRONIC TECH CO LTD
- Filing Date
- 2022-11-17
- Publication Date
- 2026-05-19
AI Technical Summary
In traditional RF transceiver architectures, the separate frequency generation, power amplification, and local oscillator distribution circuits result in high power consumption, large chip area, and high cost, making it difficult to meet the low power consumption requirements of IoT radar sensors.
An integrated circuit design employing an active negative resistance generation module, a multi-coil magnetic coupling feedback module, a digital frequency modulation module, and a DC power supply module achieves a high-power, low-power frequency source through magnetic coupling feedback and digital frequency modulation, eliminating the need for a local oscillator buffer stage.
A high-power, low-power magnetically coupled RF frequency source was achieved, reducing chip area and cost, while optimizing phase noise performance and the driving capability of the frequency source.
Smart Images
Figure CN115800925B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of radio frequency source circuit design technology, and more specifically, to a magnetically coupled high-power radio frequency source integrated circuit. Background Technology
[0002] With the rise of the Internet of Things (IoT) and the development of radio frequency (RF) integrated circuit processes and technologies, radar sensing and wireless technologies are moving towards lower cost and lower power consumption, with battery power becoming the future trend. The deployment of large-scale indoor sensor nodes places higher demands on the energy efficiency of RF transceivers. In traditional RF transceiver architectures, frequency generation, power amplification, and local oscillator distribution circuits are separate, resulting in high power consumption, making it difficult to meet the power consumption requirements of the entire system. Furthermore, the multi-module discrete solution results in a larger chip area and a corresponding increase in cost.
[0003] As the most important part of an RF transmitter, the RF frequency source plays a role in generating high-precision frequencies. Due to the low conversion efficiency of DC to AC signals in the oscillator, the frequency is greatly affected by load and environmental interference. Therefore, it is often necessary to use a buffer to isolate and amplify the RF signal before driving the subsequent power stage and receiver, which increases the design complexity and power consumption cost accordingly.
[0004] IoT radar RF chips require sufficiently low chip costs. The use of passive components such as inductors inside the chip increases the chip area, resulting in excessively high costs. In order to achieve high-power frequency source signal output, the use of multiple inductors is often unavoidable in traditional designs. Summary of the Invention
[0005] This invention addresses the technical problems of large chip size, high cost, high power consumption, and low power in existing technologies by providing a high-power, low-power, small-chip-size, and low-cost magnetically coupled high-power radio frequency source integrated circuit.
[0006] To achieve the above objectives, the present invention is implemented through the above technical solution: including an active negative resistance generation module, a multi-coil magnetic coupling feedback module, a digital frequency modulation module, and a DC power supply module. The active negative resistance generation module is directly connected to the multi-coil magnetic coupling feedback module, the digital frequency modulation module, and the DC power supply module. The active negative resistance generation module is used to provide the negative resistance required by the frequency source, offset the resonant cavity loss, and convert DC power into an AC oscillation signal. The multi-coil magnetic coupling feedback module is used to realize positive feedback, further increasing the negative resistance of the active negative resistance generation module, generating greater oscillation power, providing a large voltage gain to suppress noise, and using magnetic coupling to allocate a portion of the oscillation power to the receiver's local oscillator port. The digital frequency modulation module is used to control the switching of the capacitor to realize digital frequency modulation. The DC power supply module is used to provide a DC path, supplying DC power and bias voltage to the frequency source.
[0007] Preferably, the active negative resistance generation module is equipped with a first MOSFET and a second MOSFET.
[0008] Preferably, the multi-coil magnetic coupling feedback module includes a first inductor, a second inductor, and a third inductor; the first and second inductors are coupled by a magnetic field, the second and third inductors are coupled by a magnetic field, and the first and third inductors are coupled by a magnetic field; the first and second inductors form positive feedback to improve the negative resistance and swing of the frequency source and effectively suppress the phase noise of the frequency source, and the third inductor provides coupling energy for the local oscillator of the receiver.
[0009] Preferably, a power supply voltage is also provided, one end of the first resistor is connected to the power supply voltage, and the other end of the first resistor is connected to the tap of the first inductor and the tap of the second inductor.
[0010] Preferably, the gate of the first MOSFET is connected to the first terminal of the second inductor and the first output port, the drain of the first MOSFET is connected to the first terminal of the first inductor, and the source of the first MOSFET is directly grounded; the gate of the second MOSFET is connected to the other terminal of the second inductor and the second output port, the drain of the second MOSFET is connected to the other terminal of the first inductor, and the source of the second MOSFET is directly grounded; the first terminal of the third inductor is connected to the third output port, and the other terminal of the third inductor is connected to the fourth output port.
[0011] Beneficial effects of this invention:
[0012] (1) The present invention forms positive feedback by using the first inductor and the second inductor in the multi-coil magnetic coupling feedback module to control the turns ratio of the second inductor to the first inductor, thereby increasing the voltage gain from the drain to the gate of the first MOS transistor and the second MOS transistor, effectively increasing the negative resistance of the oscillator. The large loop gain increases the output swing and load pull capability of the oscillator, but does not increase the chip area and power consumption. At the same time, the high voltage gain from the drain to the gate effectively suppresses the noise generated by the first MOS transistor and the second MOS transistor, and optimizes the phase noise performance of the oscillator.
[0013] (2) The present invention uses the third inductor in the multi-coil magnetic coupling feedback module to couple the energy to the output port as the receiver local oscillator by magnetically coupling the third inductor with the first and second inductors. This structure eliminates the use of the local oscillator buffer stage, saves power consumption and makes the design more compact. Attached Figure Description
[0014] Figure 1 This is a connection diagram of the integrated circuit module of the present invention;
[0015] Figure 2 This is a schematic diagram of the integrated circuit of the present invention;
[0016] Figure 3This is a schematic diagram of a traditional inductor-capacitor cross-coupled radio frequency source integrated circuit.
[0017] Figure 4 for Figure 2 and Figure 3 Simulation results of the negative resistance of the frequency source circuit changing with frequency;
[0018] Figure 5 for Figure 2 and Figure 3 Simulation results of voltage waveforms at the output ports of the frequency source circuit OUT1P and OUT1N;
[0019] Figure 6 for Figure 2 Simulation results of voltage waveforms at the output ports of the frequency source circuit OUT2P and OUT2N;
[0020] Figure 7 for Figure 2 and Figure 3 Simulation structure of phase noise of frequency source circuit.
[0021] In the diagram: 1. Active negative resistance generation module; 2. Multi-coil magnetic coupling feedback module; 3. Digital frequency modulation module; 4. DC power supply module. Detailed Implementation
[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.
[0023] Example 1
[0024] like Figure 1 As shown, the present invention provides a magnetically coupled high-power radio frequency source integrated circuit, comprising: an active negative resistance generation module 1, which provides the negative resistance required by the frequency source to offset resonant cavity losses and convert DC power into an AC oscillation signal; a multi-coil magnetic coupling feedback module 2, which implements positive feedback to further increase the negative resistance of the active negative resistance generation module 1, generate greater oscillation power, provide a large voltage gain to suppress noise, and allocate a portion of the oscillation power to the local oscillator port of the receiver using magnetic coupling; a digital frequency modulation module 3, which controls the switching of the switching capacitor to achieve digital frequency modulation; and a DC power supply module 4, which provides a DC path to supply DC power and bias voltage to the frequency source; wherein the active negative resistance generation module is directly connected to the multi-coil magnetic coupling feedback module, the digital frequency modulation module, and the DC power supply module.
[0025] Specifically, such as Figure 2As shown, the active negative resistance generation module 1 is equipped with a first MOSFET M1 and a second MOSFET M2; the multi-coil magnetic coupling feedback module 2 is equipped with a first inductor L1, a second inductor L2 and a third inductor L3; the digital frequency modulation module 3 is equipped with a first capacitor C. 1a Second capacitor C 1b Third capacitor C 2a Fourth capacitor C 2b Fifth capacitor C 3a The sixth capacitor C 3b Seventh capacitor C 4a Eighth capacitor C 4b The third MOSFET M3, the fourth MOSFET M4, the fifth MOSFET M5, and the sixth MOSFET M6; the DC power supply module is equipped with a first resistor R1; the frequency source integrated circuit is also equipped with a first power supply voltage V. DD First control voltage SW1, first control voltage SW2, first control voltage SW3, first control voltage SW4, first output port OUT1P, second output port OUT1N, third output port OUT2P, fourth output port OUT2N.
[0026] The first terminal of the first resistor R1 is connected to the first power supply voltage V. DD The other end of the first resistor R1 is connected to the tap of the first inductor L1 and the tap of the second inductor L2.
[0027] The gate of the first MOSFET M1 is connected to the first terminal of the second inductor L2 and the first output port OUT1P. The drain of the first MOSFET M1 is connected to the first terminal of the first inductor L1 and the first capacitor C. 1a The first terminal and the third capacitor C 2a The first terminal, the fifth capacitor C 3a The first terminal and the seventh capacitor C 4a At the first terminal, the source of the first MOSFET M1 is directly grounded;
[0028] The gate of the second MOSFET M2 is connected to the second terminal of the second inductor L2 and the second output port OUT1N. The drain of the second MOSFET M2 is connected to the second terminal of the first inductor L1 and the second capacitor C. 1b The first terminal, the fourth capacitor C 2b The first terminal, the sixth capacitor C 3b The first terminal and the eighth capacitor C 4b At the first terminal, the source of the second MOSFET M2 is directly grounded;
[0029] The drain of the third MOSFET M3 is connected to the first capacitor C. 1a At the other end, the source of the third MOSFET M3 is connected to the second capacitor C. 1b At the other end, the gate of the third MOSFET M3 is connected to the external fourth control voltage port SW4;
[0030] The drain of the fourth MOSFET M4 is connected to the third capacitor C. 2a At the other end, the source of the fourth MOSFET M4 is connected to the fourth capacitor C. 3a At the other end, the gate of the fourth MOSFET M4 is connected to the external third control voltage port SW3;
[0031] The drain of the fifth MOSFET M5 is connected to the fifth capacitor C. 3a At the other end, the source of the fifth MOSFET M5 is connected to the sixth capacitor C. 3b At the other end, the gate of the fifth MOSFET M5 is connected to the external second control voltage port SW2;
[0032] The drain of the sixth MOSFET M6 is connected to the seventh capacitor C. 4a At the other end, the source of the sixth MOSFET M6 is connected to the eighth capacitor C. 4b At the other end, the gate of the sixth MOSFET M6 is connected to the external first control voltage port SW1;
[0033] The first end of the third inductor L3 is connected to the third output port OUT2P, and the other end of the third inductor L3 is connected to the fourth output port OUT2N.
[0034] The first inductor L1 and the second inductor L2 are coupled by a magnetic field k 12 The second inductor L2 and the third inductor L3 are coupled by a magnetic field k 23 The first inductor L1 and the third inductor L3 are coupled by a magnetic field k 13 .
[0035] The specific working principle of the integrated circuit of this invention is as follows:
[0036] This embodiment is a frequency source with high power output in the frequency modulation range of 10.3 to 10.8 GHz. The frequency modulation capacitor in the digital frequency modulation module is a metal plate capacitor, and the switch is a MOSFET with the minimum process length, which optimizes loss and parasitic capacitance.
[0037] The first inductor L1 and the second inductor L2 form positive feedback through energy coupling using a magnetic field, with a coupling coefficient of k. 12 When the inductance ratio of L2 to L1 is adjusted to be close to 3, the gates of the first MOSFET M1 and the second MOSFET M2 are amplified and sent to the first output port OUT1P and the second output port OUT1N. This amplified voltage swing effectively suppresses the phase noise of the frequency source.
[0038] The transformer formed by the first inductor L1 and the second inductor L2 provides transconductance enhancement, which multiplies the drain negative resistance of the first MOS transistor M1 and the second MOS transistor M2 in the active negative resistance module. This is beneficial for the frequency source to start oscillation and improves the frequency source's ability to drive the load.
[0039] A transformer consisting of a third inductor L3, a first inductor L1, and a second inductor L2 is used to form magnetic coupling, with coupling coefficients k and k respectively. 13 and k 23 The energy from the frequency source is transferred to OUT2P and OUT2N for the local oscillator drive of the receiver mixer.
[0040] In the DC bias module, the first resistor R1 is used to provide the frequency source with a suitable DC current and bias voltage. Adjusting its value can control the frequency source oscillation swing and output power.
[0041] like Figure 3 As shown, Figure 3 The circuit is Figure 2 The circuit is based on the original circuit, but the second inductor L2 and the third inductor L3 are removed, while all other circuit parameters remain the same.
[0042] like Figure 4 As shown, Figure 4 for Figure 2 and Figure 3 The circuit simulation results are shown in the graph. The vertical axis represents the magnitude of the negative resistance, and the horizontal axis represents the frequency. Figure 2 and Figure 3 The circuit is set to a power supply voltage of 1.2V, and the power consumption is exactly the same. At a frequency of 10.5GHz, Figure 2 The magnitude of the negative resistance generated by the circuit is Figure 3 The circuit generates nearly three times the negative resistance, and this is true over a wide frequency range. Figure 2 The negative resistance generated by the circuit is greater than Figure 3 The large negative resistance generated proves that the provided magnetic coupling feedback module can effectively increase the negative resistance of the frequency source, thereby reducing the start-up requirements of the frequency source and improving its load-carrying capacity.
[0043] like Figure 5 As shown, Figure 5 for Figure 2 and Figure 3 The simulation results of the circuit are shown, with time on the horizontal axis and voltage amplitude on the vertical axis. Figure 5 The curve represents the instantaneous voltage difference between the first output port OUT1P and the second output port OUT1N. Figure 2 and Figure 3 Comparing the simulation results, Figure 2 The instantaneous voltage at the output port of the circuit is Figure 3 The fact that the provided magnetic coupling feedback module can effectively improve the frequency source output swing is three times that of the provided magnetic coupling feedback module.
[0044] like Figure 6 As shown, Figure 6 for Figure 2 The simulation results of the circuit are shown, with time on the horizontal axis and voltage amplitude on the vertical axis. Figure 6 The curve represents the instantaneous voltage difference between the third output port OUT2P and the fourth output port OUT2N, with a peak-to-peak value of about 1V. This can be used by the local oscillator to provide frequency conversion to the receiver mixer without the need for a local oscillator buffer stage.
[0045] like Figure 7 As shown, Figure 7 for Figure 2 and Figure 3 The simulation results of the circuit show that the horizontal axis represents the offset frequency of the oscillation frequency, and the vertical axis represents the phase noise. Figure 2 Phase noise ratio of the circuit Figure 3 The phase noise of the circuit is close to 3dB, which proves that the provided magnetic coupling feedback module can continuously generate noise from the frequency source.
[0046] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A magnetically coupled high-power radio frequency source integrated circuit, characterized in that, The system includes an active negative resistance generation module, a multi-coil magnetic coupling feedback module, a digital frequency modulation module, and a DC power supply module. The active negative resistance generation module is directly connected to the multi-coil magnetic coupling feedback module, the digital frequency modulation module, and the DC power supply module. The active negative resistance generation module is equipped with a first MOSFET and a second MOSFET. The multi-coil magnetic coupling feedback module is equipped with a first inductor, a second inductor, and a third inductor. The first inductor and the second inductor are coupled through a magnetic field, and the second inductor and the third inductor are coupled through a magnetic field. The first inductor and the second inductor form positive feedback to improve the negative resistance and swing of the frequency source, and effectively... To suppress frequency source phase noise, the third inductor provides coupling energy to the receiver's local oscillator; the gate of the first MOSFET is connected to the first terminal of the second inductor and the first output port, the drain of the first MOSFET is connected to the first terminal of the first inductor, and the source of the first MOSFET is directly grounded; the gate of the second MOSFET is connected to the other terminal of the second inductor and the second output port, the drain of the second MOSFET is connected to the other terminal of the first inductor, and the source of the second MOSFET is directly grounded; the first terminal of the third inductor is connected to the third output port, and the other terminal of the third inductor is connected to the fourth output port; the DC power supply module includes a first resistor; The active negative resistance generation module is used to provide the negative resistance required by the frequency source, offset the resonant cavity loss, and convert DC power into AC oscillation signal. The multi-coil magnetic coupling feedback module is used to achieve positive feedback, which further increases the negative resistance of the active negative resistance generation module, generates greater oscillation power, provides a large voltage gain to suppress noise, and uses magnetic coupling to allocate a portion of the oscillation power to the receiver's local oscillator port. The digital frequency modulation module is used to control the switching on and off of the switched capacitor to achieve digital frequency modulation. The DC power supply module is used to provide a DC path, supplying DC power and bias voltage to the frequency source.
2. The magnetically coupled high-power radio frequency source integrated circuit according to claim 1, characterized in that, A power supply voltage is also provided. One end of the first resistor is connected to the power supply voltage, and the other end of the first resistor is connected to the taps of the first inductor and the taps of the second inductor.