CN111130497B - Filtering device and microwave metering test system - Google Patents
Filtering device and microwave metering test system Download PDFInfo
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- CN111130497B CN111130497B CN201911353851.3A CN201911353851A CN111130497B CN 111130497 B CN111130497 B CN 111130497B CN 201911353851 A CN201911353851 A CN 201911353851A CN 111130497 B CN111130497 B CN 111130497B
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- 238000001914 filtration Methods 0.000 title claims abstract description 38
- 238000012360 testing method Methods 0.000 title claims abstract description 16
- 230000001629 suppression Effects 0.000 claims description 37
- 238000004891 communication Methods 0.000 claims description 9
- 238000005259 measurement Methods 0.000 abstract description 11
- 238000000034 method Methods 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 6
- 238000001228 spectrum Methods 0.000 description 4
- 230000006978 adaptation Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/46—Filters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/30—Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R21/00—Arrangements for measuring electric power or power factor
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Acoustics & Sound (AREA)
- Filters And Equalizers (AREA)
Abstract
The application discloses a filtering device, which comprises: the device comprises a control unit, a first program control switch, a second program control switch and a filter bank; the first program control switch and the second program control switch are single-pole multi-throw switches, one end of the first program control switch is used for receiving the input of microwave signals, and the other end of the first program control switch is respectively connected with the input ends of all filters in the filter bank; one end of the second program control switch is respectively connected with the output end of each filter in the filter bank, and the other end of the second program control switch is used for outputting a filtered signal; the control unit is used for receiving an upper computer instruction, and controlling the on-off of the first program control switch and the second program control switch so as to access a filter required to be gated to a microwave signal path. The application does not need manual operation, simplifies operation steps and realizes automation of the power measurement process in microwaves. In addition, the application also provides a microwave metering test system with the technical effects.
Description
Technical Field
The invention relates to the technical field of filtering, in particular to a filtering device and a microwave metering test system.
Background
In the measurement and test of the power meter in the microwave, since the harmonic suppression of the high-power signal in the output after passing through the microwave power amplifier is generally not more than 20dBc, the measurement of the microwave power is about 1% error. In order to improve the accuracy of medium-high power measurement, the signal is usually filtered at the front end of measurement so as to remove components such as harmonic waves and the like and improve the purity of the frequency spectrum.
However, the frequency range of 10MHz to 3.5GHz spans 350 octaves, and a single filter cannot meet the filtering requirement of such a wide frequency. In the prior art, the adopted technical means is to manually access the corresponding filter according to the test frequency to achieve the filtering effect, so that the operation is complicated, and the automation of power measurement cannot be realized.
Disclosure of Invention
The invention aims to provide a filtering device and a microwave metering test system so as to simplify the filtering operation steps and realize the automation of microwave power measurement.
In order to solve the above technical problems, the present invention provides a filtering device, including: the device comprises a control unit, a first program control switch, a second program control switch and a filter bank;
the first program control switch and the second program control switch are single-pole multi-throw switches, one end of the first program control switch is used for receiving the input of microwave signals, and the other end of the first program control switch is respectively connected with the input ends of all filters in the filter bank; one end of the second program control switch is respectively connected with the output end of each filter in the filter bank, and the other end of the second program control switch is used for outputting a filtered signal; the control unit is used for receiving an upper computer instruction, and controlling the on-off of the first program control switch and the second program control switch so as to access a filter required to be gated to a microwave signal path.
Optionally, the filter bank comprises a plurality of LC low-pass filters, and the filtering frequencies of the filters are combined to cover the range of 10 MHz-3.5 GHz.
Optionally, the filter bank includes at least 12 filters, and the first programmable switch and the second programmable switch are single pole 12 throw switches.
Optionally, the working parameters and performance parameters of the filter are:
the frequency band of the first filter is 10M-16 MHz, the cut-off frequency is 16MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the second filter is 16M-25 MHz, the cut-off frequency is 25MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the third filter is 25M-40 MHz, the cut-off frequency is 40MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fourth filter is 40M-60 MHz, the cut-off frequency is 60MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fifth filter is 60M-100 MHz, the cut-off frequency is 100MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the sixth filter is 100M-165 MHz, the cut-off frequency is 165MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the seventh filter is 165M-275 MHz, the cut-off frequency is 275MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eighth filter is 275M-465 MHz, the cut-off frequency is 465MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the ninth filter is 465M-775 MHz, the cut-off frequency is 775MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the tenth filter is 775M-1290 MHz, the cut-off frequency is 1290MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eleventh filter is 1290M-2150 MHz, the cut-off frequency is 2150MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the twelfth filter is 2150M-3500 MHz, the cut-off frequency is 3500MHz, and the harmonic suppression is more than or equal to 40dBc.
Optionally, the control unit is an FPGA or a single-chip microcomputer.
Optionally, the control unit is in communication connection with the upper computer through an RS232 serial port.
Optionally, the control unit and the RS232 serial port perform data communication in a command format of 16-system coding mode.
Optionally, the control unit is in communication connection with the upper computer through a USB serial port or a 485 serial port.
In addition, the application also provides a microwave metering test system which comprises any one of the filtering devices for filtering microwave signals.
According to the filter device provided by the application, the control unit receives the instruction sent by the upper computer and controls the on-off of the first program control switch and the second program control switch so as to access the filter required to be gated to the microwave signal path. According to the filtering frequency combination of each filter in the filter bank, the signal filtering with wider frequency can be realized, the frequency spectrum purity of the test frequency signal is improved, the manual operation is not needed, the operation steps are simplified, and the automation of the power measurement process in microwaves is realized. In addition, the application also provides a microwave metering test system with the technical effects.
Drawings
For a clearer description of embodiments of the invention or of the prior art, the drawings that are used in the description of the embodiments or of the prior art will be briefly described, it being apparent that the drawings in the description below are only some embodiments of the invention, and that other drawings can be obtained from them without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a filtering apparatus according to an embodiment of the present application;
FIG. 2 is a schematic diagram of another embodiment of a filtering apparatus according to the present application;
Fig. 3 is a schematic diagram of an embodiment of an FPGA in a filter according to the present application.
Detailed Description
In order to better understand the aspects of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1, a schematic diagram of an embodiment of a filtering apparatus provided by the present application is shown in fig. 1, and the apparatus specifically includes: the control unit 1, the first program control switch 2, the second program control switch 3 and the filter bank 4;
The first programmable switch 2 and the second programmable switch 3 are single-pole multi-throw switches, one end of the first programmable switch 2 is used for receiving the input of microwave signals, and the other end of the first programmable switch is connected with the input end of each filter in the filter bank 4; one end of the second program control switch 3 is respectively connected with the output end of each filter in the filter bank 4, and the other end of the second program control switch is used for outputting a filtered signal; the control unit 1 is used for receiving an upper computer instruction, and controlling the on-off of the first program control switch 2 and the second program control switch 3 so as to access a filter requiring gating to a microwave signal path.
The filter bank comprises a plurality of LC low-pass filters, and the filtering frequencies of the filters are combined to cover the range of 10 MHz-3.5 GHz. In particular, the filter bank may comprise at least 12 filters, by means of which the frequency combination of the filtering may cover the range of 10MHz to 3.5 GHz.
According to the filter device provided by the invention, the control unit receives the instruction sent by the upper computer and controls the on-off of the first program control switch and the second program control switch so as to access the filter required to be gated to the microwave signal path. According to the filtering frequency combination of each filter in the filter bank, the signal filtering with wider frequency can be realized, the frequency spectrum purity of the test frequency signal is improved, the manual operation is not needed, the operation steps are simplified, and the automation of the power measurement process in microwaves is realized.
In a preferred embodiment, the filter set of the filter device provided by the application may specifically include 12 filters, and the first programmable switch and the second programmable switch are single-pole 12-throw switches.
The working parameters and performance parameters of the filter are as follows:
the frequency band of the first filter is 10M-16 MHz, the cut-off frequency is 16MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the second filter is 16M-25 MHz, the cut-off frequency is 25MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the third filter is 25M-40 MHz, the cut-off frequency is 40MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fourth filter is 40M-60 MHz, the cut-off frequency is 60MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fifth filter is 60M-100 MHz, the cut-off frequency is 100MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the sixth filter is 100M-165 MHz, the cut-off frequency is 165MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the seventh filter is 165M-275 MHz, the cut-off frequency is 275MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eighth filter is 275M-465 MHz, the cut-off frequency is 465MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the ninth filter is 465M-775 MHz, the cut-off frequency is 775MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the tenth filter is 775M-1290 MHz, the cut-off frequency is 1290MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eleventh filter is 1290M-2150 MHz, the cut-off frequency is 2150MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the twelfth filter is 2150M-3500 MHz, the cut-off frequency is 3500MHz, and the harmonic suppression is more than or equal to 40dBc.
In the filtering device provided by the application, the control unit can be specifically an FPGA or a single-chip microcomputer. Of course, other elements are also possible, and are not limited herein.
Taking the control unit as an example, the FPGA is adopted for implementation, and a schematic diagram of another specific implementation mode of the filtering device provided by the application is shown in fig. 2, and the filtering device specifically comprises 2 programmable single-pole multi-throw switches, a filter bank, a power supply unit and a control unit. The single-pole multi-throw switch adopts a single-pole 12-throw coaxial high-power microwave switch, the filter bank consists of 12 high-power coaxial filters, and the filtering frequencies of the 12 high-power coaxial filters are combined to cover the range of 10 MHz-3.5 GHz.
Furthermore, in the filtering device provided by the application, the control unit can be in communication connection with the upper computer specifically through an RS232 serial port. In addition, the control unit can be also connected with the upper computer through a USB serial port or a 485 serial port in a communication way, and the implementation of the application is not affected.
A schematic diagram of an embodiment of an FPGA in a filter provided by the application is shown in FIG. 3. The device is communicated with an external computer through an RS232 serial port, and drives two single-pole multi-throw high-power switches to switch channels.
And the control unit and the RS232 serial port are in data communication by adopting a command format of a 16-system coding mode. The command format of serial communication adopts a 16-system coding mode, for example, 1 channel is closed, and only a '1' code is sent through RS232, a 'C' code is sent, and 12 channels are closed.
The filter bank is composed of 12 medium-power LC low-pass filters according to the frequency range of 10MHz to 3.5GHz, and the operating frequency band and main performance of each filter are specified in table 1.
TABLE 1
In this embodiment, when the filtering device works, the control unit receives the control command information sent by the external computer through the RS232 serial port, and the FPGA control unit drives the two high-power coaxial microwave switches of the two 1 throws 12 to act respectively according to the received control information, and connects a filter requiring gating to the microwave signal path, so as to implement power signal filtering and improve the spectral purity of the test frequency signal.
In addition, the application also provides a microwave metering test system which comprises any filtering device for filtering microwave signals.
The application is applied to the field of automatic measurement and test of power in microwaves of 100W and below, and the filtering device is controlled by microcomputer programs to filter out harmonic wave, clutter and other components in the medium power signal with the frequency of 10 MHz-3.5 GHz, so that the frequency spectrum purity of the power signal is improved, and the high-accuracy automatic measurement requirement of the power signal with the frequency of 10 MHz-3.5 GHz is met.
In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, so that the same or similar parts between the embodiments are referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative elements and steps are described above generally in terms of functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The software modules may be disposed in Random Access Memory (RAM), memory, read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
The filtering device and the microwave metering test system provided by the invention are described in detail above. The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present invention and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims.
Claims (3)
1. A filtering apparatus, comprising: the device comprises a control unit, a first program control switch, a second program control switch and a filter bank;
The first program control switch and the second program control switch are single-pole multi-throw switches, one end of the first program control switch is used for receiving the input of microwave signals, and the other end of the first program control switch is respectively connected with the input ends of all filters in the filter bank; one end of the second program control switch is respectively connected with the output end of each filter in the filter bank, and the other end of the second program control switch is used for outputting a filtered signal; the control unit is used for receiving an upper computer instruction, and controlling the on-off of the first program control switch and the second program control switch so as to access a filter required to be gated to a microwave signal path; the control unit is an FPGA or a singlechip; the control unit is in communication connection with the upper computer through an RS232 serial port; the control unit and the RS232 serial port are in data communication by adopting a command format of a 16-system coding mode;
the filter bank comprises a plurality of LC low-pass filters, and the filtering frequencies of the filters are combined to cover the range of 10 MHz-3.5 GHz;
the filter bank comprises at least 12 filters, and the first program-controlled switch and the second program-controlled switch are single-pole 12-throw switches;
The working parameters and performance parameters of the filter are as follows:
the frequency band of the first filter is 10M-16 MHz, the cut-off frequency is 16MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the second filter is 16M-25 MHz, the cut-off frequency is 25MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the third filter is 25M-40 MHz, the cut-off frequency is 40MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fourth filter is 40M-60 MHz, the cut-off frequency is 60MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the fifth filter is 60M-100 MHz, the cut-off frequency is 100MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the sixth filter is 100M-165 MHz, the cut-off frequency is 165MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the seventh filter is 165M-275 MHz, the cut-off frequency is 275MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eighth filter is 275M-465 MHz, the cut-off frequency is 465MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the ninth filter is 465M-775 MHz, the cut-off frequency is 775MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the tenth filter is 775M-1290 MHz, the cut-off frequency is 1290MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the eleventh filter is 1290M-2150 MHz, the cut-off frequency is 2150MHz, and the harmonic suppression is more than or equal to 40dBc; the frequency band of the twelfth filter is 2150M-3500 MHz, the cut-off frequency is 3500MHz, and the harmonic suppression is more than or equal to 40dBc.
2. The filtering device of claim 1, wherein the control unit is communicatively connected to the host computer via a USB serial port or a 485 serial port.
3. A microwave metrology testing system comprising a filtering device according to any one of claims 1 to 2 for filtering microwave signals.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911353851.3A CN111130497B (en) | 2019-12-25 | 2019-12-25 | Filtering device and microwave metering test system |
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| CN201911353851.3A CN111130497B (en) | 2019-12-25 | 2019-12-25 | Filtering device and microwave metering test system |
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| CN111130497B true CN111130497B (en) | 2024-08-13 |
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| CN111865253A (en) * | 2020-07-08 | 2020-10-30 | 上海威固信息技术股份有限公司 | Program-controlled LC filter based on I2C protocol and sine wave generation method |
| CN111756356A (en) * | 2020-07-08 | 2020-10-09 | 上海威固信息技术股份有限公司 | Program-controlled microstrip filter based on UART protocol and sine wave generation method |
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| CN207588819U (en) * | 2018-01-31 | 2018-07-06 | 成都泰格微电子研究所有限责任公司 | A kind of L frequency ranges multi-channel switch wave filter group |
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| US9190699B2 (en) * | 2011-10-13 | 2015-11-17 | Rf Micro Devices, Inc. | Band switch with switchable notch for receive carrier aggregation |
| CN108377155A (en) * | 2018-02-02 | 2018-08-07 | 广州慧睿思通信息科技有限公司 | A kind of multi-standard, multiband, miniaturization communication receiver apparatus |
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| CN207588819U (en) * | 2018-01-31 | 2018-07-06 | 成都泰格微电子研究所有限责任公司 | A kind of L frequency ranges multi-channel switch wave filter group |
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