CN111769830A - Broadband local oscillation circuit and local oscillation signal generating method - Google Patents
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- H—ELECTRICITY
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- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/085—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal
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- H—ELECTRICITY
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- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/07—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop using several loops, e.g. for redundant clock signal generation
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- H—ELECTRICITY
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- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
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- H03L7/18—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop
Abstract
The invention discloses a broadband local oscillator circuit and a local oscillator signal generation method, aiming at the problems of lower normalized noise, limited VCO frequency range, phase discrimination leakage and poor reference leakage suppression of the frequency synthesizer of the current monolithic integrated VCO, a phase-locked loop structure is formed by a frequency synthesizer without the VCO and a frequency synthesizer internally integrated with a VCO matrix; a directional coupler, an amplifier and a high-pass filter are adopted in a phase-locked loop to form a feedback path, so that the phase-locked loop has the performances of high phase noise, wide frequency band, high phase demodulation leakage inhibition degree, high reference leakage inhibition degree and the like; the local oscillator circuit can be well miniaturized, the requirement of miniaturized use is met, and the operability and the practicability are good.
Description
Technical Field
The present invention relates to the field of communications technologies, and in particular, to a wideband local oscillation circuit and a local oscillation signal generation method.
Background
Frequency sources have found widespread use in many areas such as electronic countermeasure, radar, telemetry, and telecommunications, and are referred to as the "heart" of many electronic systems. The local oscillator is an indispensable part in the up-conversion link and the down-conversion link of the receiver, and the performance of the local oscillator, such as output frequency range, phase noise, harmonic suppression, spurious suppression, frequency hopping time and frequency stability, is of great importance to the influence of the whole system.
Currently, frequency synthesis techniques can be classified into three types, including direct frequency synthesis (DS), Phase Locked Loop (PLL) and direct digital frequency synthesis (DDS). The direct frequency synthesis technology can realize low phase noise and fast frequency hopping, but the output frequency band range is narrow, the volume is large, and the integration is difficult. The phase-locked loop frequency synthesis technique can realize low phase noise, but has a problem of slow frequency conversion time. The direct digital frequency synthesis technology starts from a phase angle, adopts the Nyquist sampling theorem, carries out frequency synthesis through a digital sampling storage technology, has short frequency conversion time, continuous phase, high frequency resolution, easy control and high stability, is convenient for realizing signal modulation in a complex mode, and also has the problems of abundant stray components, limited highest frequency of a synthesized signal, large power consumption and the like.
The current trend of frequency synthesis is to combine and use direct frequency synthesis (DS), phase-locked loop (PLL), direct digital frequency synthesis (DDS), etc. to improve the technical indexes of frequency synthesizer, such as phase noise, spurious indexes, frequency hopping time and output frequency range, etc., by utilizing their respective advantages.
In document 1, a high-performance frequency source research and implementation based on a DDS + PLL technology (the master thesis 2004.11 of the wang national defense science and technology university) adopts an implementation scheme of exciting a phase-locked loop (PLL) by using a direct digital frequency synthesis (DDS), so as to obtain a 600MHz sampling clock frequency source with high frequency stability, low phase noise and low spurious.
In document 2, in the research on an 8-18 GHz broadband microwave frequency source module (li zhang national electronic science major paper 2010.03), a PLL circuit structure is directly excited by an L-band frequency source using a DDS, frequency hopping work of the frequency source is controlled by an FPGA, and a VCO is replaced by an YTO, thereby achieving a better 8-18 GHz broadband frequency output comprehensive technical index.
In document 3, in research on ultra-wideband microwave frequency source technology (li-brightness electronic science thesis 2006.4), a mixed frequency synthesis scheme of DDS + PLL is used to realize an output with a low-end frequency of 2 to 4GHz, a frequency spreading from 2 to 4GHz to 2 to 12GHz is realized by a segmented amplification and frequency doubling link, and a microwave switch controls the frequency selection output. The whole system adopts single-ring phase locking to control the VCO, outputs 2-12 GHz ultra-wideband frequency, and realizes a small-size and low-cost microwave frequency source.
In document 4, "research and design of a low-phase noise frequency source" (liuyuan kun electronic science master paper 2018.3), a scheme of complex loop sampling phase locking + DDS + frequency doubling is adopted to realize design and implementation, and a low-phase noise, low-spurious agility frequency source which outputs a 5.4GHz-10.8GHz frequency signal in a wide frequency band is realized.
In document 5, in a design of a low spurious frequency source based on a fractional-frequency phase-locked loop (Yan Chong, Wangqiang, Li Xiao Hui, Madong Lei), a frequency source with an output frequency of 1500-2500 MHz, a frequency step of 250kHz, a phase noise of-90 dBc/Hz @10kHz, a spurious suppression degree of less than-65 dBc and an output power of +5dBm is designed by adopting a phase-locked loop chip with an internally integrated voltage-controlled oscillator based on a fractional-frequency phase-locked loop technology.
Document 8, research on phase-locked frequency sources in C-band and X-band (zhang south kyo university of science 2007.6), uses a frequency synthesis chip ADF41O6 with the addition of different VCOs to implement two phase-locked frequency sources of 5.5GHz and 8.76 GHz.
Document 9, "60 MHz-12 GHz broadband frequency source research" (the master electronic science thesis 2010.03), frequency generation part adopts a YTO fractional-N frequency-division phase-locked loop to generate a fundamental frequency signal of 2 GHz-6 GHz, and then the fundamental frequency signal is extended, and a method combining down-conversion, frequency division and frequency multiplication technologies is used to cover the whole frequency band. Realizes partial functions of a 60 MHz-12 GHz frequency source model machine.
In documents 1 to 4, a DDS + PLL circuit, in documents 5 to 8, a classical phase-locked loop circuit, in document 9, a PLL + DS circuit, and in document 10, a DS circuit structure are used to generate signals with different output frequency ranges, and in document 11, two single-pole single-throw switches are respectively added to two links to achieve channel isolation of two signals. The above documents mainly start from a circuit configuration or a channel link, and improve the spectral quality of a signal from one or more aspects, but still have certain problems.
Disclosure of Invention
The invention provides a broadband local oscillator circuit and a local oscillator signal generating method aiming at the technical problems in the prior art, and realizes the output of local oscillator signals with high reference leakage suppression degree, high phase discrimination leakage suppression degree, broadband, high phase noise and high integration.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the broadband local oscillator circuit comprises a first frequency synthesis unit, a second frequency synthesis unit, a control unit, a directional coupler, an amplifier, a high-pass filter, a first switch circuit and a second switch circuit;
the first frequency synthesis unit comprises a first R frequency divider, a first N frequency divider, a first phase detector, a first charge pump and a first loop filter, wherein the first R frequency divider and the first N frequency divider are respectively coupled to the input end of the first phase detector, and the first phase detector, the first charge pump and the first loop filter are sequentially coupled;
the second frequency synthesis unit comprises a second R frequency divider, a second N frequency divider, a second phase discriminator, a second charge pump, a second loop filter and a VCO matrix unit, wherein the second R frequency divider and the second N frequency divider are respectively coupled to the input end of the second phase discriminator, the second charge pump and the second loop filter are sequentially coupled, and the output end of the VCO matrix unit is coupled to the input end of the second N frequency divider;
the control unit is respectively coupled with the first frequency synthesis unit and the second frequency synthesis unit through communication interfaces to realize information transmission;
the input end of the first switch circuit is used for connecting a reference input, one output end of the first switch circuit is coupled with the input end of the first R frequency divider, and the other output end of the first switch circuit is coupled with the input end of the second R frequency divider and is used for switching control of the reference input, the first frequency synthesis unit and the second frequency synthesis unit;
the output end of the second switch circuit is coupled with the input end of the VCO matrix unit, and the two input ends of the second switch circuit are respectively coupled with the output ends of the first loop filter and the second loop filter and used for switching control of the VCO matrix unit, the first loop filter and the second loop filter;
and the output end of the VCO matrix unit is coupled with the input end of a directional coupler, and the coupling end of the directional coupler is coupled to the first N frequency divider sequentially through an amplifier and a high-pass filter.
In the foregoing technical solution, further, the first frequency synthesis unit employs a VCO-less frequency synthesizer, and the second frequency synthesis unit employs a frequency synthesizer internally integrated with a VCO matrix.
In the above technical solution, the second frequency synthesizing unit further includes a VCO calibrating unit and a sigma-delta modulator.
In the above technical solution, further, the first switch unit and the second switch unit are single-pole double-throw switches.
In the above technical solution, further, the control unit includes an FPGA chip and a FLASH unit externally hung thereon.
The invention also provides a local oscillation signal generating method based on the broadband local oscillation circuit, which comprises the following steps:
s1, switching the first switch circuit to connect the reference input to the second R frequency divider;
s2, switching the second switch circuit to connect the second loop filter with the VCO matrix unit, and forming a phase-locked loop in the second frequency synthesis unit;
s3, configuring the second frequency synthesis unit as a calibration mode, and configuring register parameters of the second frequency synthesis unit to lock the output frequency;
s4, reading parameters of full frequency coverage and certain frequency stepping of the VCO matrix unit in the self-locking mode of the second frequency synthesis unit, and storing the parameters into the FLASH unit for subsequent calling;
s5, switching the first switch circuit to connect the reference input to the first R frequency divider;
s6, switching a second switch circuit to connect the first loop filter with the VCO matrix unit and form a phase-locked loop by the first frequency synthesis unit, the VCO matrix unit, the directional coupler, the amplifier and the high-pass filter;
s7, configuring the register parameter of the first frequency synthesis unit, configuring the second frequency synthesis unit to be in manual mode, and calling the VCO matrix unit parameter in the step S4 according to the output frequency to lock the output frequency of the phase-locked loop in the step S6.
The invention has the following beneficial effects:
aiming at the problems of low normalized noise, limited VCO frequency range, phase discrimination leakage and poor reference leakage suppression of the conventional frequency synthesizer of the monolithic integrated VCO, a frequency synthesizer without the VCO and a frequency synthesizer internally integrated with a VCO matrix are adopted to form a phase-locked loop structure; a feedback path is formed by adopting a directional coupler, an amplifier and a high-pass filter in a phase-locked loop, and the low-frequency reference frequency is suppressed by the isolation index of the directional coupler, the reverse isolation of the amplifier and the amplitude-frequency characteristic of the high-pass filter, so that the phase-locked loop has the performances of high phase noise, wide frequency band, high phase demodulation leakage suppression degree, high reference leakage suppression degree and the like.
The invention adopts the mode of combining the frequency synthesizer without the VCO and the frequency synthesizer internally integrated with the VCO matrix for use, can well realize the miniaturization of the local oscillator circuit, meets the requirement of miniaturization use, and has good operability and practicability.
Drawings
Fig. 1 is a schematic diagram of a wideband local oscillator circuit according to the present invention.
Fig. 2 is a control flow chart of a local oscillation signal generating method according to the present invention.
Fig. 3a) is a phase detection leakage actual diagram with a local oscillator output frequency of 8.054GHz in embodiment 1 of the present invention.
Fig. 3b) is a reference leakage actual map of local oscillator output frequency 8.054GHz in embodiment 1 of the present invention.
Fig. 3c) is a phase noise actual diagram of the local oscillator output frequency of 8.054GHz in embodiment 1 of the present invention.
Fig. 4a) is a phase detection leakage actual diagram with a local oscillator output frequency of 4.368GHz in embodiment 2 of the present invention.
Fig. 4b) is a reference leakage actual map of local oscillator output frequency 4.368GHz in embodiment 2 of the present invention.
Fig. 4c) is a phase noise actual map of local oscillator output frequency 4.368GHz in embodiment 2 of the present invention.
Fig. 5a) is a phase detection leakage actual diagram with a local oscillator output frequency of 5.3808GHz in embodiment 2 of the present invention.
Fig. 5b) is a reference leakage actual map of local oscillator output frequency 5.3808GHz in embodiment 2 of the present invention.
Fig. 5c) is a phase noise actual map of local oscillator output frequency 5.3808GHz in embodiment 2 of the present invention.
Fig. 6a) is a phase detection leakage actual diagram with a local oscillator output frequency of 11.369GHz in embodiment 2 of the present invention.
Fig. 6b) is a reference leakage actual map of local oscillator output frequency 11.369GHz in embodiment 2 of the present invention.
Fig. 6c) is a phase noise actual map of local oscillator output frequency 11.369GHz in embodiment 2 of the present invention.
In the figure: 100. a first frequency synthesis unit 101, a first R frequency divider 102, a first N frequency divider 103, a first phase detector 104, a first charge pump 105 and a first loop filter;
200. a second frequency synthesis unit 201, a second R-divider 202, a second N-divider 203, a second phase detector 204, a second charge pump 205, a second loop filter 206, a VCO matrix unit 207, a VCO calibration unit 208, a sigma-delta modulator;
300. the circuit comprises an FPGA chip, 400 parts of a directional coupler, 500 parts of an amplifier, 600 parts of a high-pass filter, 700 parts of a FLASH unit, 800 parts of a first switch circuit, 900 parts of a second switch circuit.
Detailed Description
The wideband local oscillator circuit shown in fig. 1 includes a first frequency synthesizing unit 100, a second frequency synthesizing unit 200, a control unit, a directional coupler 400, an amplifier 500, a high pass filter 600, a first switch circuit 800, and a second switch circuit 900.
The first frequency synthesis unit 100 adopts a VCO-less frequency synthesizer, and includes a first R frequency divider 101, a first N frequency divider 102, a first phase detector 103, a first charge pump 104, and a first loop filter 105, where the first R frequency divider 101 and the first N frequency divider 102 are respectively coupled to an input end of the first phase detector 103, and the first phase detector 103, the first charge pump 104, and the first loop filter 105 are sequentially coupled.
The second frequency synthesis unit 200 adopts a frequency synthesizer with an internal integrated VCO matrix, and includes a second R frequency divider 201, a second N frequency divider 202, a second phase detector 203, a second charge pump 204, a second loop filter 205, and a VCO matrix unit 206, where the second R frequency divider 201 and the second N frequency divider 202 are respectively coupled to an input end of the second phase detector 203, the second charge pump 204, and the second loop filter 205 are sequentially coupled, and an output end of the VCO matrix unit 206 is coupled to an input end of the second N frequency divider 202.
The control unit comprises an FPGA chip 300 and an FLASH unit 700 hung on the FPGA chip, and is respectively coupled with SPI interfaces of the VCO-free frequency synthesis unit 100 and the VCO matrix integrated inside frequency synthesis unit 200, so that information transmission of the control unit, the first frequency synthesis unit and the second frequency synthesis unit is realized.
The first switching circuit 800 employs a single-pole double-throw switch; the first switch circuit 800 has an input terminal for connecting to a reference input, an output terminal coupled to the input terminal of the first R frequency divider 101, and another output terminal coupled to the input terminal of the second R frequency divider 201, for controlling the switching of the reference input with the first frequency synthesizing unit and the second frequency synthesizing unit.
The second switching circuit 900 employs a single-pole double-throw switch; the output terminal of the second switch circuit 900 is coupled to the VCTRL terminal of the VCO matrix unit 206, and two input terminals thereof are coupled to the output terminals of the first loop filter 105 and the second loop filter 205, respectively, for controlling the switching between the voltage control terminal VCTRL of the VCO matrix unit and the first loop filter and the second loop filter.
The output RF _ out of the VCO matrix unit 206 is coupled to the input of the directional coupler 400, the coupling terminal of the directional coupler 400 is coupled to the input of the amplifier 500, the output of the amplifier 500 is coupled to the input of the high pass filter 600, and the output of the high pass filter 600 is coupled to the input RF _ in of the first N frequency divider 102, so as to form a feedback path of the phase lock loop in the local oscillator circuit.
The frequency synthesizer with the VCO matrix integrated therein in this embodiment further includes a VCO calibration unit 207 and a sigma-delta modulator 208.
The following describes, with reference to fig. 1 and 2, a local oscillation signal generation method based on the wideband local oscillation circuit, which specifically includes the following steps:
s1, the single-pole double-throw switch SW1 is switched to the 2 terminal, the reference input is connected to the second R frequency divider, and the reference signal enters the second frequency synthesis unit through a REF _ in2 port;
s2, switching the single-pole double-throw switch SW2 to the 2 end, connecting the second loop filter with the VCTRL end of the VCO matrix unit, and forming a phase-locked loop in the second frequency synthesis unit;
s3, configuring the second frequency synthesis unit as a calibration mode, and configuring the value of each register of the second frequency synthesis unit to lock the output frequency;
s4, reading parameters of full frequency coverage and certain frequency stepping of the VCO matrix unit under the self-locking mode of the second frequency synthesis unit by using a self-programming calibration program, saving the parameters as an excel file, and storing the excel file into the FLASH unit for subsequent calling;
s5, switching the single-pole double-throw switch SW1 to the 1 end, connecting the reference input to the first R frequency divider, and leading the reference signal to enter the first frequency synthesis unit through the REF _ in1 port;
s6, switching a single-pole double-throw switch SW2 to a 1 end, connecting a first loop filter to a VCTRL end of a second frequency synthesis unit, connecting the first loop filter with a VCO matrix unit, and enabling the first frequency synthesis unit, the VCO matrix unit, a directional coupler, an amplifier and a high-pass filter to form a phase-locked loop;
s7, configuring the value of each register in the first frequency synthesis unit, configuring the second frequency synthesis unit as a manual mode, and only using the VCO matrix unit of the second frequency synthesis unit; and calling the VCO matrix cell parameters stored in the FLASH cell in the step S4 according to the output frequency to lock the output frequency of the phase-locked loop in the step S6.
The following further describes the present invention with reference to specific embodiments and test data, and the present invention uses the wideband local oscillator circuit and the local oscillator signal generating method to implement local oscillator outputs covering two different frequency ranges, which are specifically as follows:
example 1
Frequency coverage range: 8 ~ 16 GHz's local oscillator frequency output, signal amplitude: +6dBm +/-3 dB, 100MHz reference frequency input, 50MHz phase discrimination frequency, phase noise less than or equal to-100 dBc/Hz @10kHz (1 GHz radio frequency input), and the reference leakage, phase discrimination leakage and phase noise actual measurement data are shown in fig. 3a), fig. 3b) and fig. 3 c).
From fig. 3c), the phase noise index was calculated to be-81.176-10 lg 100-101.176 dBc/Hz (radio frequency input 1 GHz).
Example 2
Frequency coverage range: 3.4 ~ 11.4 GHz's local oscillator frequency output, signal amplitude: 7dBm +/-3 dB, 102.4MHz reference frequency input, 102.4MHz phase discrimination frequency, less than or equal to-108 dBc/Hz @10kHz phase noise (1 GHz radio frequency input).
1) The local oscillator output frequency is 4.368GHz, the radio frequency input is 1GHz, and the reference leakage, the phase discrimination leakage and the phase noise measured data are shown in fig. 4a), fig. 4b) and fig. 4 c). From fig. 4c), the phase noise index was calculated to be-89.042-10 lg 100-109.042 dBc/Hz (radio frequency input 1 GHz).
2) The local oscillator output frequency is 5.3808GHz, and reference leakage, phase detection leakage and phase noise measured data are shown in fig. 5a), fig. 5b) and fig. 5 c). From fig. 5c), the phase noise index was calculated to be-86.005-10 lg 100-106.005 dBc/Hz.
3) When the local oscillator output frequency is 11.369GHz, the reference leakage, the phase detection leakage, and the phase noise measured data are shown in fig. 6a), fig. 6b), and fig. 6 c). From fig. 6c), the phase noise index was calculated to be-81.534.005-10 lg 100-101.534 dBc/Hz.
The present specification and figures are to be regarded as illustrative rather than restrictive, and it is intended that all such alterations and modifications that fall within the true spirit and scope of the invention, and that all such modifications and variations are included within the scope of the invention as determined by the appended claims without the use of inventive faculty.
Claims (6)
1. The broadband local oscillator circuit is characterized by comprising a first frequency synthesis unit, a second frequency synthesis unit, a control unit, a directional coupler, an amplifier, a high-pass filter, a first switch circuit and a second switch circuit;
the first frequency synthesis unit comprises a first R frequency divider, a first N frequency divider, a first phase detector, a first charge pump and a first loop filter, wherein the first R frequency divider and the first N frequency divider are respectively coupled to the input end of the first phase detector, and the first phase detector, the first charge pump and the first loop filter are sequentially coupled;
the second frequency synthesis unit comprises a second R frequency divider, a second N frequency divider, a second phase discriminator, a second charge pump, a second loop filter and a VCO matrix unit, wherein the second R frequency divider and the second N frequency divider are respectively coupled to the input end of the second phase discriminator, the second charge pump and the second loop filter are sequentially coupled, and the output end of the VCO matrix unit is coupled to the input end of the second N frequency divider;
the control unit is respectively coupled with the first frequency synthesis unit and the second frequency synthesis unit through communication interfaces to realize information transmission;
the input end of the first switch circuit is used for connecting a reference input, one output end of the first switch circuit is coupled with the input end of the first R frequency divider, and the other output end of the first switch circuit is coupled with the input end of the second R frequency divider and is used for switching control of the reference input, the first frequency synthesis unit and the second frequency synthesis unit;
the output end of the second switch circuit is coupled with the input end of the VCO matrix unit, and the two input ends of the second switch circuit are respectively coupled with the output ends of the first loop filter and the second loop filter and used for switching control of the VCO matrix unit, the first loop filter and the second loop filter;
and the output end of the VCO matrix unit is coupled with the input end of a directional coupler, and the coupling end of the directional coupler is coupled to the first N frequency divider sequentially through an amplifier and a high-pass filter.
2. The wideband local oscillator circuit of claim 1, wherein the first frequency synthesis unit employs a VCO-less frequency synthesizer and the second frequency synthesis unit employs a frequency synthesizer with an internally integrated VCO matrix.
3. The wideband local oscillator circuit of claim 2, wherein the second frequency synthesizer unit further comprises a VCO calibration unit and a sigma-delta modulator.
4. The wideband local oscillator circuit according to claim 1, wherein the first and second switching units are single-pole double-throw switches.
5. The broadband local oscillator circuit according to claim 1, wherein the control unit comprises an FPGA chip and a FLASH unit externally attached thereto.
6. A local oscillator signal generating method based on the broadband local oscillator circuit according to any one of claims 1 to 5, comprising the steps of:
s1, switching the first switch circuit to connect the reference input to the second R frequency divider;
s2, switching the second switch circuit to connect the second loop filter with the VCO matrix unit, and forming a phase-locked loop in the second frequency synthesis unit;
s3, configuring the second frequency synthesis unit as a calibration mode, and configuring register parameters of the second frequency synthesis unit to lock the output frequency;
s4, reading parameters of full frequency coverage and certain frequency stepping of the VCO matrix unit in the self-locking mode of the second frequency synthesis unit, and storing the parameters into the FLASH unit for subsequent calling;
s5, switching the first switch circuit to connect the reference input to the first R frequency divider;
s6, switching a second switch circuit to connect the first loop filter with the VCO matrix unit and form a phase-locked loop by the first frequency synthesis unit, the VCO matrix unit, the directional coupler, the amplifier and the high-pass filter;
s7, configuring the register parameter of the first frequency synthesis unit, configuring the second frequency synthesis unit to be in manual mode, and calling the VCO matrix unit parameter in the step S4 according to the output frequency to lock the output frequency of the phase-locked loop in the step S6.
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| CN116647232A (en) * | 2023-07-26 | 2023-08-25 | 成都世源频控技术股份有限公司 | Frequency source synthesis circuit for improving frequency hopping time |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4409563A (en) * | 1981-02-26 | 1983-10-11 | General Electric Company | Phase locked loop frequency synthesizer with frequency compression loop |
| CN105429641A (en) * | 2015-12-16 | 2016-03-23 | 贵州航天计量测试技术研究所 | Lock protection type high-performance broadband microwave frequency synthesizer |
| CN205356307U (en) * | 2015-12-31 | 2016-06-29 | 陕西烽火实业有限公司 | Frequency synthesizer of short wave receiver |
| CN106656176A (en) * | 2016-12-30 | 2017-05-10 | 重庆华伟工业（集团）有限责任公司 | Wide-frequency-band agile frequency synthesizer |
| WO2018126800A1 (en) * | 2017-01-09 | 2018-07-12 | 成都西蒙电子技术有限公司 | Low-phase-noise frequency synthesizer |
| CN109450445A (en) * | 2018-10-26 | 2019-03-08 | 中国电子科技集团公司第四十研究所 | A kind of variable loop bandwidth frequency synthesizer, system and method |
| CN212850458U (en) * | 2020-08-06 | 2021-03-30 | 成都凌德科技有限公司 | Broadband local oscillator circuit |
-
2020
- 2020-08-06 CN CN202010782694.4A patent/CN111769830A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4409563A (en) * | 1981-02-26 | 1983-10-11 | General Electric Company | Phase locked loop frequency synthesizer with frequency compression loop |
| CN105429641A (en) * | 2015-12-16 | 2016-03-23 | 贵州航天计量测试技术研究所 | Lock protection type high-performance broadband microwave frequency synthesizer |
| CN205356307U (en) * | 2015-12-31 | 2016-06-29 | 陕西烽火实业有限公司 | Frequency synthesizer of short wave receiver |
| CN106656176A (en) * | 2016-12-30 | 2017-05-10 | 重庆华伟工业（集团）有限责任公司 | Wide-frequency-band agile frequency synthesizer |
| WO2018126800A1 (en) * | 2017-01-09 | 2018-07-12 | 成都西蒙电子技术有限公司 | Low-phase-noise frequency synthesizer |
| CN109450445A (en) * | 2018-10-26 | 2019-03-08 | 中国电子科技集团公司第四十研究所 | A kind of variable loop bandwidth frequency synthesizer, system and method |
| CN212850458U (en) * | 2020-08-06 | 2021-03-30 | 成都凌德科技有限公司 | Broadband local oscillator circuit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116647232A (en) * | 2023-07-26 | 2023-08-25 | 成都世源频控技术股份有限公司 | Frequency source synthesis circuit for improving frequency hopping time |
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