CN206818771U - A kind of high steady clock source and CC types radar test and fault detection system - Google Patents
A kind of high steady clock source and CC types radar test and fault detection system Download PDFInfo
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- CN206818771U CN206818771U CN201720757778.6U CN201720757778U CN206818771U CN 206818771 U CN206818771 U CN 206818771U CN 201720757778 U CN201720757778 U CN 201720757778U CN 206818771 U CN206818771 U CN 206818771U
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Abstract
The utility model discloses a kind of high steady clock source and CC types radar test and fault detection system, belong to radar test and testing equipment field, solve the problems, such as clock source stability and anti-interference difference in existing radar sensing system.The utility model includes PXI e interface, FPGA, crystal oscillator energy supply control module, high stability constant-temperature crystal oscillator and power management and electric source filter circuit module, PXI e interface connection computer is power management and electric source filter circuit module for power supply, power management and electric source filter circuit module are FPGA and crystal oscillator energy supply control module is powered, FPGA receives the signal of PXI e interface transmission, and whether control crystal oscillator energy supply control module is the power supply of high stability constant-temperature crystal oscillator.The utility model can control high steady clock source in real time, can save power consumption, and closing high steady clock source in good time as needed can make the platform interior temperature be maintained at a more stable state, beneficial to the stable continuous firing of instrument.
Description
Technical field
The utility model belongs to radar test and testing equipment field, has high steady clock more specifically to one kind
The CC types radar test and fault detection system in source.
Background technology
China New Generation Weather Radar has played important function in terms of diastrous weather monitoring and Warning Service, in order to ensure thunder
Run up to regular traffic, domestic many technical guarantee personnel have accumulated many experiences, such as king in terms of accident analysis and maintenance
Will force (Wang Zhiwu, Zhou Honggen, Lin Zhongnan, China New Generation Weather Radar SA＆B accident analysis [J] modern radars, 2005,27
(1)：16-17,28) similar fault that more than ten of CINRAD SA/B radar occurs etc. is collected and arranged, is pointedly proposed
Some strengthen the measure of China New Generation Weather Radar reliability and the opinion of the machine radar performance.Beam gold dollar (beam gold dollar, CINRAD/
CC radar transmitter high voltage power supply repair methods and fault diagnosis example [J] Shanxi are meteorological, and 2005, (3)：33-34,36) pass through analysis
CINRAD/CC radar transmitter high voltage power supply operation principles, and propose by fault diagnosis example the repair method of high voltage power supply.Make
Arranged net for China Meteorological Administration's weather service the equipment used, CINRAD/CC types radar have higher reliability, stability good compared with
Good maintainability, when radar breaks down, according to the instruction alarm condition of warning message combination maintenance control panel, makes and sentencing accordingly
It is disconnected, according to each System Working Principle and signal flow, and the circuit that directly maintenance is thought with alarm parameters.But there is some performances ginseng
Failure caused by number index decline is not main malfunction monitoring point, and radar monitoring system, which can not detect, to be out of order and report
Police is, it is necessary to the reason for technical staff finds out failure by analysis and trouble point.
CC types radar test uses the portable general instrument of NI companies to be contained for hardware platform with fault detection system
Signal source, frequency spectrograph, oscillograph, universal meter and power meter.Wherein signal source and frequency spectrograph common sparing board, other instruments is equal
Can independently it use.Due to cost and volume reason, the onboard clock stability of all purpose instrument that NI companies release is generally relatively low, by
Temperature has a great influence, and in radar test, and Spectrometry analysis bandwidth would generally be arranged to 3Hz and following, so all purpose instrument
Onboard clock can not meet requirement of the radar system to tester clock completely.
The content of the invention
1st, to solve the problems, such as
Clock source stability and anti-interference difference and signal source be present for existing CC types radar fault detecting system
With the frequency stability of frequency spectrograph it is not high the problem of, the utility model provides a kind of high steady clock source, is gone by FPGA instruction
The switch to crystal oscillator output signal is realized, power consumption can be saved, improve the stability and anti-interference of clock source.The utility model
A kind of CC types radar test and fault detection system with the steady clock source of the height are additionally provided, as needed the high steady clock of control
Source switch can make the internal system temperature be maintained at a more stable state, beneficial to the stable continuous firing of instrument.
2nd, technical scheme
To solve the above problems, the utility model adopts the following technical scheme that.
A kind of high steady clock source, including PXI e interface, FPGA, crystal oscillator energy supply control module, high stability constant-temperature crystal oscillator and
Power management and electric source filter circuit module, described PXI e interface connection computer is power management and electric source filter circuit mould
Block is powered, and described power management and electric source filter circuit module are powered for FPGA and crystal oscillator energy supply control module, described
FPGA receives the signal of PXI e interface transmission, and whether control crystal oscillator energy supply control module is the power supply of high stability constant-temperature crystal oscillator.
Further, described FPGA is XC6SLX45T, described PXIe buses and FPGA HSSI High-Speed Serial Interface company
Connect, realize that standard PXIe communicates.
Further, described crystal oscillator energy supply control module is spx3819 series LDO devices.
Further, it is that FPGA power supplies are Switching Power Supply moulds in described power management and electric source filter circuit module
Block, its model PTH08T230WAD.
Further, described high stability constant-temperature crystal oscillator is SOXO18U series crystal oscillators.
Further, in power input prime using resolution element design LC power-supply filters, after LC power-supply filters
Into electromagnetic interface filter, described power management and electric source filter circuit module are then injected into.
Further, its output clock frequency is 10MHz, exports clock power >=7dBm, harmonic wave≤- 30dBc；Clutter
≤-80dBc。
A kind of CC types radar test and fault detection system, including above-mentioned high steady clock source, it is signal source or frequency spectrograph
Stable clock signal is provided.
Further, in addition to oscillograph and/or universal meter, described universal meter is connected with CC type radars, for surveying
Measure its voltage or electric current；Described oscillograph is used for the change in electric for measuring CC type radars.
3rd, beneficial effect
(1) the utility model provides a kind of high steady clock source, goes to realize to crystal oscillator output signal by FPGA instruction
Switch, power consumption can be saved, improve the stability and anti-interference of clock source；When the clock source that the present apparatus provides is not used,
CC radar tests are low to frequency measurement and improvement factor test accuracy with fault detection system.Using after this clock source, CC
Radar test and the frequency spectrograph in fault detection system and signal source clock quality are high, and the spectrum measurement degree of accuracy is high, and signal is defeated
Go out frequency test signal precision height；
(2) the utility model can control high steady clock source in real time, can save power consumption；Due to CC radar tests and failure
Detecting system is the portable stage of integration, and closing high steady clock source in good time as needed can protect the platform interior temperature
Hold in a more stable state, beneficial to the stable continuous firing of instrument；
(3) frequency of the utility model energy stabilization signal source and frequency spectrograph output, simple in construction, reasonable in design, user
Just.
Brief description of the drawings
Fig. 1 is the structural representation of high steady clock source in the utility model；
Fig. 2 is the structural representation of detecting system of the present utility model；
Fig. 3 is circuit construction of electric power schematic diagram in the utility model；
Fig. 4 is crystal oscillator energy supply control module circuit diagram in the utility model.
Embodiment
The utility model is further described below with reference to specific embodiment.
Embodiment 1
The steady clock source of height in the utility model is by PXI e interface, FPGA (field programmable gate array), crystal oscillator power supply control
Molding block, high stability constant-temperature crystal oscillator (10MHz), power management and electric source filter circuit module composition, its structure such as Fig. 1 institutes
Show.PXI e interface connection computer is power management and electric source filter circuit module for power supply, power management and electric source filter circuit
Module is FPGA and crystal oscillator energy supply control module is powered, and FPGA receives the signal of PXI e interface transmission, controls crystal oscillator power supply
Whether module is the power supply of high stability constant-temperature crystal oscillator.
The course of work of the present utility model is：It is connected by PXI e interface with computer, is filtered to power management and power supply
Wave circuit module provides power supply, and power management and electric source filter circuit module are FPGA and crystal oscillator energy supply control module is powered, by
FPGA goes to control crystal oscillator energy supply control module switch, by the parameter of return, decides whether to export crystal oscillation signal.In CC type radars
When test uses universal meter or oscillograph with fault detection system, PXIe, which is sent, closes clock source order, passes through FPGA instruction
Go to realize the closing to crystal oscillator output signal；When using signal source or frequency spectrograph, PXIe, which is sent, opens clock source order, passes through
FPGA instruction goes to realize the opening to crystal oscillator output signal, and clock source provides clock signal for signal source or frequency spectrograph.In CC
In type radar test and fault detection system, universal meter is used to detect the signals such as the voltage, electric current, resistance of CC type radars, and will
The signal detected is transferred to the processing terminal of detecting system, and oscillograph is used to change, show the CC detected in detecting system
The change in electric of type radar.
The advantages of technical scheme：1. high steady clock source can be controlled in real time, power consumption can be saved；2. because CC radars are surveyed
Examination is integrated portable stage with fault detection system, and closing high steady clock source can be maintained at the platform interior temperature
One more stable state, beneficial to the stable continuous firing of instrument；3. the frequency of stabilization signal source output；4. stable frequency spectrograph is defeated
The frequency gone out.
In the utility model, because the power supply signal that computer is provided by PXI e interface is produced by Switching Power Supply, power supply
Noise is larger, causes crystal oscillator output clock quality to be deteriorated.So in the present system, the control of power quality is particularly important.Power supply
Using the method for LC filtering plus EMI filtering, its effect is that have larger inhibition to the interference signal of high frequency for filtering.EMI is filtered
Ripple device is a kind of low pass filter being made up of inductance and electric capacity, and it can allow the useful signal of low frequency to pass through, and to high frequency
Interference has inhibitory action.Power input prime is using resolution element design LC power-supply filters, and power-supply filter is by LC group of networks
Into its action principle is so that the impedance of wave filter and the impedance mismatch of interference source, so that interference signal is entered along interference source
The direction come reflects back, so as to reduce the influence of interference source.Enter electromagnetic interface filter after LC power-supply filters, be then injected into electricity
Power management circuits.The effect of electromagnetic interface filter：For export 10MHz signal when, it is caused interference be mainly common mode disturbances, EMI
Mainly by using the method for suppression common mode, for the earthing of casing, with a magnet ring string around 2-3 circle meetings pair on ground wire
More than 10MHZ interference has larger attenuation；The iron core that may be selected to be close to transformer glues copper foil, copper foil closed loop.Handle rear end
Export the absorbing circuit of rectifying tube and the size of primary big circuit in parallel electric capacity.
As shown in figure 3, in power management of the present utility model and electric source filter circuit module, wherein being supplied to FPGA electricity
Source is all produced by switch power module, and its model PTH08T230WAD, output current is up to 6A, meets that FPGA kernels power up
When requirement to electric current.
DC/DC conversion is into variable DC voltage, also referred to as DC chopped-wave by fixed DC voltage conversion.Chopper
Working method have two kinds, first, pulse width modulation mode Ts is constant, change ton (general), second, frequency modulated mode, ton is not
Become, change Ts (being also easy to produce interference).Its specific circuit is by following several classes：
(1) Buck circuits-- buck chopper, it exports average voltage Uo and is less than input voltage Ui, and polarity is identical.
(2) Boost circuit-- boost chopper, it exports average voltage Uo and is more than input voltage Ui, and polarity is identical.
(3) Buck-Boost circuits-- buck or boost chopper, it exports average voltage Uo and is more than or less than input
Voltage Ui, opposite polarity, inductive transmission.
(4) Cuk circuits-- buck or boost chopper, it exports average voltage Uo and is more than or less than input voltage UI,
Opposite polarity, capacitive transmission.
Current soft switch technique causes DC/DC, and there occurs a variety of ECI that qualitative leap, VICOR companies of the U.S. manufacture and design
Sofe Switch DC/DC converters, its peak power output have 300W, 600W, 800W etc., corresponding power density for (6,2,10,
17)W/cm3, efficiency is (80-90) %.A kind of height using soft switch technique of the Japanese newest release of NemicLambda companies
Frequency switch power module RM series, its switching frequency is (200~300) kHz, and power density has reached 27W/cm3, using synchronization
Rectifier (MOS-FET replaces Schottky diode), is that whole circuit efficiency brings up to 90%.The advantages of circuit design：
1. design is simple：A power module is only needed, mixes a small amount of discrete component, you can obtains power supply.
2. shorten the construction cycle：Modular power source be generally provided with it is a variety of input, output selection, user can also repeat superposition or
Intersect superposition, form building block system integrated drive generator, realize multichannel input, output, reduce the model machine development time significantly.
3. become more flexible：Product design such as needs to change, and need to only change or another suitable power source module in parallel.
4. technical requirements are low：Modular power source is commonly equipped with standardizing front end, highly integrated power module and other elements, therefore
Make Power Management Design simpler.
5. module power source casing, which has, collects heat sink, radiator and the Trinitarian structure type of shell, modular power source is realized
The conduction type of cooling, the temperature value of power supply is leveled off to minimum value, meanwhile, impart the bag that modular power source has golden coat only again
Dress.
It is 6. of fine quality reliable：Modular power source is generally using full-automatic production, and be equipped with high-tech production technology, therefore product
Matter is stable, reliable.
It is 7. widely used：Modular power source can be widely applied to Aero-Space, locomotive naval vessel, military project weapons, generation distribution, postal
Telecommunication, metallurgical mine, automatically control, each neck of the social production such as household electrical appliance, instrument and meter and scientific experiment and life
Domain, especially play irreplaceable important function in highly reliable and high-tech sector.
For FPGA using the XC6SLX45T for matching company of SEL, the device has 43661 logic units, 54576 triggerings
Device, 2088Kb memory spaces, 58 DSP units and 4 pairs of high-speed serial communication interfaces.In the utility model, PXIe buses
Be directly connected to FPGA HSSI High-Speed Serial Interface and can be achieved standard PXIe communications, Content of Communication include crystal oscillator power supply and
Crystal oscillator power supply status.
Crystal oscillator power supply uses the spx3819 series LDO devices of Sipex companies, and spx3819 series low-dropout regulators have
Low noise, high accuracy, reverse battery protection, low quiescent current and have the advantages that output enable.With enabled control terminal,
Can the measurement of clock when not needed when, cut off crystal oscillator power supply, so as to improve measurement accuracy.As shown in figure 4, in systems, FPGA
Station command is responded, when using this test system instrument, sends and opens crystal oscillator power command, after FPGA receives order, control
OSC_PW_CTL level, you can the opening of crystal oscillator power supply is realized, sends and closes crystal oscillator power command, after FPGA receives order, control
OSC_PW_CTL level processed, you can realize the closing of crystal oscillator power supply.
High stability constant-temperature crystal oscillator uses the SOXO18U series of products that existing ELECSPN companies provide, the series of products
Small volume, low in energy consumption, fast and stable, it is widely used in the fields such as military-civil communication, test measurement.
The key technical indexes
1st, output clock frequency：10MHz；
2nd, clock power is exported：≥7dBm；
3rd, harmonic wave：≤-30dBc；
4th, clutter：≤-80dBc；
5th, output frequency stability：±0.5ppm；
6th, phase noise：-170dBc@100kHz.
Claims (9)
- A kind of 1. high steady clock source, it is characterised in that：It is permanent including PXI e interface, FPGA, crystal oscillator energy supply control module, high stability Warm crystal oscillator and power management and electric source filter circuit module, described PXI e interface connection computer are that power management and power supply are filtered Wave circuit module for power supply, described power management and electric source filter circuit module are FPGA and crystal oscillator energy supply control module is powered, Described PXI e interface is connected with FPGA, and described FPGA output ends are connected with crystal oscillator energy supply control module, described crystal oscillator electricity Source control module is connected with high stability constant-temperature crystal oscillator, for its power supply；Described high stability constant-temperature crystal oscillator output clock signal.
- A kind of 2. high steady clock source according to claim 1, it is characterised in that：Described FPGA is XC6SLX45T, described PXIe buses and FPGA HSSI High-Speed Serial Interface connect, realize standard PXIe communicate.
- A kind of 3. high steady clock source according to claim 2, it is characterised in that：Described crystal oscillator energy supply control module is Spx3819 series LDO devices.
- A kind of 4. high steady clock source according to claim 1, it is characterised in that：Described power management and power filter electricity It is switch power module to be powered in the module of road for FPGA, its model PTH08T230WAD.
- A kind of 5. high steady clock source according to claim 1, it is characterised in that：Described high stability constant-temperature crystal oscillator is SOXO18U series crystal oscillators.
- A kind of 6. high steady clock source according to claim 4, it is characterised in that：Resolution element is used in power input prime LC power-supply filters are designed, enter electromagnetic interface filter after LC power-supply filters, are then injected into described power management and power filter Circuit module.
- A kind of 7. high steady clock source according to claim 1, it is characterised in that：Its output clock frequency is 10MHz, output Clock power >=7dBm, harmonic wave≤- 30dBc；Clutter≤- 80dBc.
- 8. a kind of CC types radar test and fault detection system, it is characterised in that：Including described in any one in claim 1-7 High steady clock source, stable clock signal is provided for signal source or frequency spectrograph.
- 9. a kind of CC types radar test according to claim 8 and fault detection system, it is characterised in that：Also include oscillography Device and/or universal meter, described universal meter is connected with CC type radars, for measuring its voltage or electric current；Described oscillograph is used In the change in electric of measurement CC type radars.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113147619A (en) * | 2020-12-29 | 2021-07-23 | 江汉大学 | New energy vehicle |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113147619A (en) * | 2020-12-29 | 2021-07-23 | 江汉大学 | New energy vehicle |
| CN113147619B (en) * | 2020-12-29 | 2024-05-28 | 江汉大学 | New energy vehicle |
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