CN201600445U - 1GHz-50GHz coaxial attenuation calibrator - Google Patents
1GHz-50GHz coaxial attenuation calibrator Download PDFInfo
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- CN201600445U CN201600445U CN2010201070028U CN201020107002U CN201600445U CN 201600445 U CN201600445 U CN 201600445U CN 2010201070028 U CN2010201070028 U CN 2010201070028U CN 201020107002 U CN201020107002 U CN 201020107002U CN 201600445 U CN201600445 U CN 201600445U
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- voltage divider
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Abstract
The utility model relates to a 1GHz-50GHz coaxial attenuation calibrator comprising a radio frequency signal source, a local oscillation signal source, a frequency mixer, a semi-automatic induction voltage divider and a narrowband measuring receiver, wherein the radio frequency signal source and the local oscillation signal source are connected with the narrowband measuring receiver through the frequency mixer; and the semi-automatic induction voltage divider is connected with the narrowband measuring receiver. The coaxial attenuation calibrator has the measured frequency up to 50GHz, simultaneously has small signal receiving capacity and good stability and repeatability, and satisfies the requirement for quantity transfer on the frequency band attenuation parameters in China.
Description
Technical field
The utility model relates to millimeter wave attenuation measurement device, particularly relates to the coaxial attenuation measurement device of 1GHz～50GHz.
Background technology
The Microwave Radio attenuation parameter is an extremely important and universal parameter in the radio survey field, all pays much attention to the attenuation parameter establishment of standard both at home and abroad.For example country measures the attenuation measurement national standard device that institute sets up, frequency range 30MHz～18GHz.The highest measurement standard of national defence decay is based upon respectively on 1MHz～18GHz and two frequency ranges of 26.5GHz～40GHz at present, and wherein 26.5GHz～40GHz decay highest standard is the 8mm Wave guide system.And, still do not have this standard in the world for the 18GHz～50GHz attenuation standard of coaxial system, it is also incomplete that domestic standard covers frequency range, and correlative study is not carried out in corresponding frequency conversion system and test coupling aspect yet.Continuous development along with science and technology, a large amount of coaxial systems and wideer more high band attenuator are used widely, the renewal of standards such as S parameter, signal source has also proposed new requirement to attenuation standard, existing two cover standards can not satisfy the requirement of calibration and transmission of quantity value far away, set up the standard set-up that a cover can satisfy the coaxial attenuation parameter transmission of quantity value of millimeter wave so press for.At present, existing both at home and abroad many companies have released the broadband signal generator that frequency range covers 50GHz, and upper limiting frequency is to the measuring receiver of 50GHz, for example E8257D of Agilent company, N5531S, the SMR50 of R/S company, FSMR-50 etc.These broadband instruments all are coaxial systems, and their attenuation parameter needs the attenuator of higher standard to be its calibration.In addition, some Other Instruments are such as the S of network analyzer
21Parameter is when setting up the 50GHz standard, and its problem of tracing to the source also can't solve.If set up cover coaxial (2.4mm/2.92mm) 18GHz～50GHz attenuating device, existing 1MHz～18GHz attenuation standard before adding, above-mentioned difficulties can be resolved.So be badly in need of setting up the coaxial attenuation standard of this frequency range, to satisfy the active demand that present attenuation parameter amount passes.
Last century six the seventies, the domestic TO7 decay calibrating installation of having developed has obtained widespread usage at home.To the eighties latter stage, the 8902S measuring receiver that Hewlett-Packard Corporation produces has generally replaced TO7.The attenuation measurement instrument mainly contains R﹠amp at present; The VM-7 attenuation measurement device that N5531S measuring receiver that the FSMR measuring receiver that S company produces, Agilent company produce and WE company produce.8902S and VM-7 stop production at present, and FSMR and N5531S belong to the composite measurement instrument, except measuring decay, can also measure power level, the purity of frequency spectrum etc., but cost an arm and a leg, therefore be badly in need of a kind of calibrating installation of decaying to satisfy the demand of home market.
Summary of the invention
The purpose of this utility model is to avoid above-mentioned deficiency of the prior art that a kind of 1GHz～50GHz is provided coaxial attenuation measurement device, make the survey frequency of coaxial attenuation standard device reach 50GHz, satisfied domestic transmission of quantity value demand this frequency range attenuation parameter.
The technical solution of the utility model is:
The coaxial attenuation measurement device of 1GHz～50GHz, comprise: radio-frequency signal source, local oscillation signal source, frequency mixer, semi-automatic inductive voltage divider, arrowband measuring receiver, described radio-frequency signal source, local oscillation signal source link to each other with described arrowband measuring receiver by described frequency mixer, and described semi-automatic inductive voltage divider links to each other with described arrowband measuring receiver.
Described arrowband measuring receiver comprises: successively the isolating transformer of Xiang Lianing, in advance put with filtration module and link to each other successively in put and filtration module, direct current detection module, A/D and driver module, the described end that is connected described semi-automatic inductive voltage divider with filtration module of putting is in advance put the other end that is connected described semi-automatic inductive voltage divider with filtration module in described.
Described radio-frequency signal source through tested attenuator, isolate the input end of attenuator to frequency mixer, described local oscillation signal source is connected in another input end of frequency mixer, an output terminal of frequency mixer is connected in described putting in advance and filtration module through isolating transformer.
Described put in advance with filtration module, in put with filtration module, direct current detection module and A/D and driver module in include power filtering module.
Described semi-automatic inductive voltage divider comprises inductive voltage divider and intrinsic standoff ratio control device, and described intrinsic standoff ratio control device comprises the dial-up driving switch, at least one data collecting card and at least one block I/O interface card; Described dial-up driving switch links to each other with inductive voltage divider, and described data collecting card and I/O interface card are connected in series on the dial-up driving switch successively.
The interpolation type pci bus compatibility of described I/O interface card and computing machine.
The driving switch of described semi-automatic inductive voltage divider is provided with shaft joint, and an end of this shaft joint links to each other with the driving switch of described inductive voltage divider, and the other end links to each other with described dial-up driving switch by data line.
Advantage of the present utility model is:
The survey frequency of the coaxial attenuation standard device of the utility model has reached 50GHz, has the small-signal receiving ability simultaneously, has good stable and repeatability, has satisfied domestic transmission of quantity value demand to this frequency range attenuation parameter.
Description of drawings
Fig. 1 is the utility model structure principle chart;
Fig. 2 is the structural representation block scheme of semi-automatic inductive voltage divider.
Embodiment
The utility model has adopted the technical scheme of series connection Low Medium Frequency method of substitution.Synthesized source (requiring synchronic base) has been adopted in radio-frequency signal source and local oscillation signal source, this quasi-instrument has very high frequency stability and accuracy and up to the frequency resolution of 1Hz, this has just guaranteed 1kHz intermediate-freuqncy signal frequency stability and the accuracy after the mixing.Adopted isolation attenuator, reduced the mismatch problems in the systematic survey process with better standing-wave ratio (SWR) characteristic.Adopted the fundamental wave mixing mode, made system have bigger dynamic range and signal to noise ratio (S/N ratio) preferably.It is transformed to the 1kHz intermediate-freuqncy signal by the frequency transformation mode linearly with radio frequency and microwave signal, inductive voltage divider as the primary standard device in system adopts series system to be connected with tested attenuator, has finished the process that substitutes by twice balance (zeroing) of system.The major advantage of this device is to have avoided using high target wide band radio-frequency and the microwave standard attenuator that is difficult to realization.Adopting the high sensitivity low noise operational amplifier is the 1kHz arrowband measuring receiver of main development, has very high sensitivity (135dBm) and bigger dynamic range (120dB).Utilize frequency of operation for the accurate semi-automatic inductive voltage divider of 1kHz as benchmark, thereby utilize accurately the change amount of intrinsic standoff ratio to substitute tested radio frequency and the damping capacity of microwave attenuator reaches the purpose of measuring damping capacity accurately and effectively.Since adopted these new technology and equipments make this decay calibrating installation and other principle formation the decay calibrating installation mutually specific energy reach higher accuracy of measurement.
The operating frequency range of this decay calibrating installation is 1GHz～50GHz, has adopted the working method of fundamental wave mixing, and signal source and local vibration source all adopt the scan synthesis signal source, and two signal sources adopt the mode of synchronic base to connect.Frequency of operation (CW) by the requirement signalization source of measured piece exports tested attenuator to after interior fixed ampllitude, arrive frequency mixer then.The medium frequency output end of the 1kHz intermediate-freuqncy signal process frequency mixer behind radio frequency and the local oscillator difference frequency is delivered to the pre-amplification module of 1kHz intermediate-frequency receiver, and frequency mixer will keep the amplitude characteristic of radiofrequency signal constant in frequency conversion process linearly.Utilization substitutes the damping capacity of tested attenuator as the change amount of the intrinsic standoff ratio of the inductive voltage divider of intermediate frequency standard attenuator.Because tested attenuator and inductive voltage divider are in the system of being connected, so the working method of this system is called as the series connection method of substitution.The process that this measuring system is measured tested attenuator is: at first according to the requirement of tested attenuator with the frequency configuration of radio frequency and local vibration source to required Frequency point, the output level of local vibration source is set to+10dBm, and the level of radio-frequency signal source is set to-10dBm.Tested attenuator (being generally variable attenuator) is placed initial decay amount A
0(zero graduation) position, the inductive voltage divider intrinsic standoff ratio places D
0The position, the signal level (according to by the damping capacity of school attenuator) of regulating receiver gain and radio frequency source makes the 1kHz receiver obtain balance indication (equilibrium level is designated as zero); Then tested attenuator is placed damping capacity A to be measured
1The position, because the variation of damping capacity, make system's out of trim this moment in cascade system.Regulate the inductive voltage divider intrinsic standoff ratio once more and make system's balance once more, and read intrinsic standoff ratio D this moment
1The attenuation incrementation A of tested attenuator then
xFor:
For stepping or variable attenuator, repeat the decrement measurement value that above-mentioned measuring process just can obtain variant decay gear behind the change decay scale.Above inductive voltage divider is automanual, so all adopt way of hardware and software combination to carry out to the data read and the data processing of inductive voltage divider, need not to carry out artificial reading and calculating again.
As shown in Figure 1, the utility model comprises radio-frequency signal source 1, local oscillation signal source 2, arrowband measuring receiver 3, semi-automatic inductive voltage divider 4, described radio-frequency signal source 1, local oscillation signal source 2 link to each other with described arrowband measuring receiver 3 respectively, and described semi-automatic inductive voltage divider 4 links to each other with described arrowband measuring receiver 3.Described narrow-band receiver 3 comprise successively putting in advance of linking to each other and filtration module 5, in put and filtration module 6, direct current detection module 7, A/D and driver module 8.Described radio-frequency signal source 1 through tested attenuator 9, isolate the input end of attenuator 10 to frequency mixer 11, described local oscillation signal source 2 is connected in another input end of frequency mixer 11, and an output terminal of frequency mixer 11 is connected in described putting in advance and filtration module 5 through isolating transformer 12.
Wherein the arrowband measuring receiver is the core component of this decay calibrating installation, enough wide dynamic range and low noise are arranged, and higher sensitivity and antijamming capability, mainly by five parts form comprise put in advance with filtration module, in put and filtration module, direct current detection module, power filtering module and A/D and driver module.Described put in advance with filtration module, in put with filtration module, direct current detection module and A/D and driver module in all include power filtering module.Below each module of arrowband measuring receiver is introduced respectively:
(1) puts in advance and filtration module
The effect of receiver in system is the intermediate-freuqncy signal after the mixing to be carried out low noise amplify in advance and filtering, when measuring maximum dynamically 80dB damping capacity, put in advance/minimum signal level of filtration module input end will reach-and (3.16 μ are v) for 97dBm.This signal level is very weak, and the first order of receiver is put/the higher technical requirement of wave filter proposition in advance, and higher sensitivity and extremely low noise figure be arranged.
Amplifier and narrow band filter have constituted the first order of whole narrow-band receiver together in advance.Because system has proposed very high technical indicator, so the first order of receiver is also had very high index request.For the cascade of N level amplifier, whole noise figure can be determined by following formula:
In the formula: F
iThe noise figure of-Di i level amplifier;
G
Ai-Di i level Amplifier Gain.
By above-mentioned formula as can be seen the noise figure of total system mainly determine by first order amplifier, so the noise figure of the selected first order amplifier of this module is a most critical.We have selected the bipolar field effect transistor amplifier of the AD743 ultra-low noise of ANALOGDEVICES company for use, its noise figure can reach 2.9nV/ √ Hz at 10kHz, and have the gain bandwidth product of good AC characteristic such as 4.5MHz and a total harmonic distortion of 0.0003% (in the 1kHz frequency), when the 1kHz left and right sides, the nearly 95dB of common-mode rejection ratio, Power Supply Rejection Ratio has 75dB.。The Low Medium Frequency signal of low noise amplifier after to mixing amplifies, and improves signal to noise ratio (S/N ratio), measures dynamic range and accuracy of measurement to improve.
(2) put in and filtration module
Along with the increase of tested attenuator damping capacity, the intrinsic standoff ratio of inductive voltage divider is reducing synchronously in measuring process, puts input end in making (86.5dBm) and the signal level of subsequent stages circuit is approximate keeps constant.In put output terminal signal level be 13.5dBm (1.06V), therefore, in the gain of putting should be 100dB (enlargement factor is 100,000 times).In to put be three grades, in put third level output terminal and be connected to three grades of wave filters, its filtering bandwidth can reach 30Hz, effectively the noise of filter out power 50Hz is used to improve quality of signals.
(3) direct current detection module
Demodulator probe has used the AD637 chip of AD company, and this chip is the converter of a high-accuracy AC value to direct current.In 0V～2V effective value input range, the non-linear of its output level maximum is 0.02%, be a pin-point accuracy, AC value is to the monolithic integrated optical circuit of DC converting.In the design of this partial circuit, the influence that reduces ripple is the design key of this circuit module.The effective means that reduces ripple is to adopt filter network, and what circuit adopted is a Sallen-Key twin-stage filter network wave filter.Through debugging, the highest 10 μ V magnitudes that are stabilized to of signal of direct current detection output have further improved the accuracy of measuring.
(4) power filtering module
For convenience and unified, we are unified in receiver has used positive and negative 15V direct supply.Because the very high sensitivity index of receiver, the inhibition of temperature characterisitic, ripple characteristics and the interference of power supply all there is very high target requirement.Therefore, we have adopted the secondary voltage regulation way in power-supply system.Prime has adopted the linear tributary of positive and negative 20V two-way stabilized voltage supply, and it is incorporated into respectively on the circuit boards at different levels.Utilize the MC1723 chip of Motorola Inc. to design independently secondary source of stable pressure respectively on every grade of circuit board.Adopt this design can improve the interference that circuit at different levels produce by electric power loop significantly.
(5) A/D and driver module
A/D and display driver circuit adopt 24 A/D converters, show final result by industrial computer.This circuit module carries out data acquisition with AD7710 to the output signal of direct current detection module, and AD7710 is a kind of ∑-Δ type 24Bit analog to digital converter.Adopt A/D and driver module after the chip design such as AD7710, have precision height, characteristics easy to use.
To put in advance at last with filtration module, in put and the assembling of filtration module, direct current detection module, power filtering module, A/D and driver module and industrial computer constitutes intermediate frequency arrowband measuring receiver, and the overall performance of receiver tested, form system with signal source and frequency mixer, carry out integration test, reached intact duty.
A kind of as shown in Figure 2 semi-automatic inductive voltage divider, semi-automatic inductive voltage divider comprises inductive voltage divider 1 and intrinsic standoff ratio control device 2, intrinsic standoff ratio control device 2 comprises the I/O interface card 5 of 3, one data capture cards 4 of dial-up driving switch and one and computing machine interpolation type pci bus compatibility; Dial-up driving switch 3 links to each other with inductive voltage divider 1 by data line, and data collecting card 4 and I/O interface card 5 are connected in series on the dial-up driving switch 3 successively by data line; Be respectively equipped with shaft joint 6 on 8 groups of driving switch of inductive voltage divider 1, an end of this shaft joint 6 links to each other with the driving switch of described inductive voltage divider 1, and the other end links to each other with described dial-up driving switch 3 by data line.
In the process that data collecting card stores data the state that reads each dial-up driving switch 3, because each dial-up driving switch 3 has 11 gears, so each dial-up driving switch 3 is divided into 11 kinds of states.By after the reading of data data being encoded, each coding is corresponding to the gear positions on the dial-up driving switch 3, show by a decimal code, code to these 8 groups of dial-up driving switch 3 synthesizes by different intrinsic standoff ratios then, constitute one 9 decimal number, the gear on each dial-up driving switch 3 marches forward one when being positioned at 10 grades.Maximum number is 100000000, and intrinsic standoff ratio is 1; Minimum is 000000000, and intrinsic standoff ratio is-∞.For example: reading is 000010000, and then intrinsic standoff ratio is 10
-4, with respect to the maximum number 80dB that decayed.
The computing machine of system support is gathered, is handled the measurement data of inductive voltage divider 1, and utilizes correlation model software that error is revised, and makes systematic survey uncertainty index reach the regulation requirement.
Claims (7)
1.1GHz the coaxial attenuation measurement device of～50GHz, it is characterized in that, comprise: radio-frequency signal source, local oscillation signal source, frequency mixer, semi-automatic inductive voltage divider, arrowband measuring receiver, described radio-frequency signal source, local oscillation signal source link to each other with described arrowband measuring receiver by described frequency mixer, and described semi-automatic inductive voltage divider links to each other with described arrowband measuring receiver.
2. the coaxial attenuation measurement device of 1GHz～50GHz as claimed in claim 1, it is characterized in that, described arrowband measuring receiver comprises: successively the isolating transformer of Xiang Lianing, in advance put with filtration module and link to each other successively in put and filtration module, direct current detection module, A/D and driver module, the described end that is connected described semi-automatic inductive voltage divider with filtration module of putting is in advance put the other end that is connected described semi-automatic inductive voltage divider with filtration module in described.
3. as claim 1, the coaxial attenuation measurement device of 2 described 1GH～50GHz, it is characterized in that described radio-frequency signal source through tested attenuator, isolate the input end of attenuator to frequency mixer, described local oscillation signal source is connected in another input end of frequency mixer, and an output terminal of frequency mixer is connected in described putting in advance and filtration module through isolating transformer.
4. the coaxial attenuation measurement device of 1GHz～50GHz as claimed in claim 2 is characterized in that, described put in advance with filtration module, in put with filtration module, direct current detection module and A/D and driver module in include power filtering module.
5. the coaxial attenuation measurement device of 1GHz～50GHz as claimed in claim 1, it is characterized in that, described semi-automatic inductive voltage divider comprises inductive voltage divider and intrinsic standoff ratio control device, described intrinsic standoff ratio control device comprises the dial-up driving switch, at least one data collecting card and at least one block I/O interface card; Described dial-up driving switch links to each other with inductive voltage divider, and described data collecting card and I/O interface card are connected in series on the dial-up driving switch successively.
6. the coaxial attenuation measurement device of 1GHz～50GHz according to claim 5 is characterized in that: the interpolation type pci bus compatibility of described I/O interface card and computing machine.
7. according to claim 5 or the coaxial attenuation measurement device of 6 described 1GHz～50GHz, it is characterized in that: the driving switch of described semi-automatic inductive voltage divider is provided with shaft joint, one end of this shaft joint links to each other with the driving switch of described inductive voltage divider, and the other end links to each other with described dial-up driving switch by data line.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103647612A (en) * | 2013-12-20 | 2014-03-19 | 北京无线电计量测试研究所 | Attenuation measurement device for waveguide system |
| CN104734656A (en) * | 2013-12-24 | 2015-06-24 | 苏州普源精电科技有限公司 | Radio frequency signal source with amplitude modulation and automatic level control functions |
| CN106841824A (en) * | 2016-12-15 | 2017-06-13 | 北京无线电计量测试研究所 | A kind of signal source comprehensive parameters field measurement apparatus |
| CN109617633A (en) * | 2018-12-19 | 2019-04-12 | 北京无线电计量测试研究所 | A kind of Attenuation measuring system and method |
| CN113534034A (en) * | 2021-06-17 | 2021-10-22 | 北京无线电计量测试研究所 | Method for calibrating transmission amplitude of on-chip S parameter standard device |
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2010
- 2010-02-03 CN CN2010201070028U patent/CN201600445U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103647612A (en) * | 2013-12-20 | 2014-03-19 | 北京无线电计量测试研究所 | Attenuation measurement device for waveguide system |
| CN103647612B (en) * | 2013-12-20 | 2015-11-04 | 北京无线电计量测试研究所 | A kind of attenuation measurement device for Wave guide system |
| CN104734656A (en) * | 2013-12-24 | 2015-06-24 | 苏州普源精电科技有限公司 | Radio frequency signal source with amplitude modulation and automatic level control functions |
| CN104734656B (en) * | 2013-12-24 | 2018-09-25 | 苏州普源精电科技有限公司 | A kind of radio-frequency signal source with amplitude modulation and automatic level control function |
| CN106841824A (en) * | 2016-12-15 | 2017-06-13 | 北京无线电计量测试研究所 | A kind of signal source comprehensive parameters field measurement apparatus |
| CN106841824B (en) * | 2016-12-15 | 2020-04-28 | 北京无线电计量测试研究所 | Signal source comprehensive parameter on-site measuring device |
| CN109617633A (en) * | 2018-12-19 | 2019-04-12 | 北京无线电计量测试研究所 | A kind of Attenuation measuring system and method |
| CN109617633B (en) * | 2018-12-19 | 2021-05-07 | 北京无线电计量测试研究所 | Millimeter wave attenuation measurement system and method |
| CN113534034A (en) * | 2021-06-17 | 2021-10-22 | 北京无线电计量测试研究所 | Method for calibrating transmission amplitude of on-chip S parameter standard device |
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| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20101006 Termination date: 20140203 |