A kind of Tacan simulator metering method and device
Technical field:
The invention belongs to radio close navigation technical field, and in particular to a kind of Tacan simulator metering method and dress
Put.
Background technology:
In early stage, air navigation wants to determine aircraft position it is necessary to use two or more Land Navigation Installations, and
And positioning precision is very low, such location technology is without too big practical value.Then, in mid-twentieth century, in order to realize
Accurate aerial location navigation, the suggestion by Fei get La Er telecommunications laboratory of the U.S. according to air force of U.S., naval, have developed Tacan system
System.The original name of Tacan is TACAN, is the abbreviation of Tactical Air Navigation System- TACAN/tacan,
It is a kind of short-range radio navigation system, tactical air navigation be in the world first can provide distance letter simultaneously for aircraft
The short-range navigation system of breath and azimuth information.In the 1950s, earliest applied to the carrier-borne of U.S. army's aircraft carrier
Machine navigates, but also is the important equipment that tanker aircraft completes air refueling mission, is developed into the North Atlantic Treaty
Organize the military short-range navigation system of standard of each member state.Tacan system is one of important navigation system of my air force, utilizes tower
Health navigation system can ensure aircraft along prebriefed pattern target, the rally of a group of planes and congregation and in complicated meteorology bar
Vector aircraft is gone home with approach etc. under part.Therefore effectively Support is of crucial importance.
Tacan simulator is the azimuth information of quantitative simulation earth station, checks, tests, the calibration main skill of Tacan airborne equipment
The special equipment of art index, the calibration method of producer is the method using " common apparatus+airborne standard Tacan+detector " at present
Carry out, common apparatus mainly calibrates the common index of Tacan simulator(Frequency, power, level, frequency spectrum etc.), airborne standard Tacan
It is to calibrate special index(Orientation, distance), detector is for providing working environment on a disengaging machine, is airborne equipment
Power supply, control working condition, measuring technology index and the function such as output test result.This " integrated correction system " be traceable into
On the simulator of mouth(The DTS102 in the U.S.).The problem of this method is present:Whole chain of tracing to the source is substantially 1:1 transmits, and is discontented with
Sufficient GJB5109 requirement;In addition, this pattern of " airborne equipment calibration detection device " belongs to metering and hung upside down, at most can only
It is checking, it is impossible to referred to as calibrate.Also there is part producer to have purchased a whole set of imported from America equipment and be used as measurement criteria, including it is airborne
Tacan DTS-200, ground installation(Tacan simulator FR-1401/1400, supporting detector, precise distance measurement simulator PDME-
200), slightly it is better than 1 using the method being directly compared with import simulator, index during metering:1.
The content of the invention:
Aircraft close navigation detection device is for airborne navigational system test and the special equipment of Fault Isolation, its performance
Whether index precisely consistent to be related to flight safety, significant.In order to solve deficiency of the prior art, the present invention needs to solve
The certainly measurement and calibration problem of aircraft close navigation detection device, the metering method and device of proposition are able to ensure that aircraft close navigation
The performance indications of detection device are accurate, solve the problems, such as that such special equipment can not measurement and calibration.
Also it is not applied in the development of Tacan simulator metering device for current radionavigational software and hardware, in tower
The present invention is based on virtual instrument and software and radio technique in terms of health simulator quantitative study, will need hardware real in conventional method
Existing modulation /demodulation function adds the compatibility and autgmentability of metering device by software desk Implementation.
Tactical air navigation is operated in 962~1213 megahertzs of frequency ranges, shares 252 radio frequency channels (X patterns and Y mode each 126
It is individual), its range accuracy is about ± 200 meters, reachable ± 1 ° of the angle measurement degree of accuracy.Coverage is by transmission power, receiving sensitivity
With the restriction of ultrashort wave line-of-sight propagation rule, typical tactical air navigation operating distance is about 370 kms.It can be accommodated simultaneously
100 airplane rangings, number of aircraft is unrestricted during angle measurement.New tactical air navigation also has air to air (aircraft is to aircraft)
Ranging and angle measurement function.Tactical air navigation uses polar coordinates (p~θ) location method, only needs a Tacan ground station can
For Plane location, therefore the tactical air for being particularly suitable for carrying out operational activity centered on airport or aircraft carrier uses.
Tactical air navigation is made up of the airborne Tacan set and ground tacan set of mutual cooperation work.Airborne Tacan is set
It is standby to include radio set, antenna, control and display device etc.;Ground tacan set includes radio set, day
Line, device etc. is monitored and controlled.System carries out ranging using interrogator-responder system, i.e., launches inquiry at random by airborne Tacan set
Pulse pair, after the reception of ground tacan set, then transponder pulse is sent in the form of pulse pair, airborne Tacan set is according to sending
Interrogation pulse is to the spread speed for receiving time that transponder pulse undergone and radio wave, you can extrapolate aircraft to Tacan
The distance of face platform.System angle measurement is realized by the phase relation between measuring basis pulse signal and pulse envelope signal
's.When aircraft is located at the different azimuth of Tacan ground station, reference pulse signal and arteries and veins received by its airborne Tacan set
Rush between envelope signal and there is different phase relations, be assured that out side of the aircraft relative to Tacan ground station whereby
Parallactic angle.
Tacan distance measuring signal produces principle:30 pairs, the interrogation pulse pair at intervals of 12 microseconds of transmitting per second on aircraft(In pairs
The pulse of transmitting), earth station receives interrogation pulse and launches the reply pulse pair that is equally spaced to rear.Aboard receive answer
The time of pulse pair compared with the time of interrogation pulse pair, draws time of the pulse radio in spatial, so as to be flown
Machine and is shown to the distance of earth station.
Tacan location signal produces principle:The directional diagram of earth station antenna emitting radio waves is in have 9 lobes heart-shaped,
And with 900 revs/min of rotations.The pulse signal that aircraft receives is amplitude-modulated form, and this amplitude modulation envelope is included by rotation heart
15 hertz of bearing signals caused by shape directional diagram and 135 hertz of bearing signals as caused by 9 lobe rotations, the phase of the two signals
It is relevant with respect to the dimensional orientation of aircraft with earth station.Reference signal is needed for measure phase, therefore when cardioid pattern turns
When crossing due east direction, one group of transmitting by 12 pulses to the reference pulse signal that forms, when 8 lobes (remove with it is heart-shaped most
That lobe of big value coincidence) in the maximum of each when turning over due east direction, also launch one group be made up of 6 pairs of pulses it is auxiliary
Help reference pulse signal.Compare the phase of 15 hertz of bearing signals and reference pulse signal, it is rough with respect to aircraft to obtain earth station
Orientation, ambiguity during accurate measurement orientation is eliminated with it.Compare the phase of 135 hertz of bearing signals and auxiliary base pulse signal
Earth station is obtained with respect to the accurate orientation values of aircraft.
The equipment important parameter measuring method
(1)Frequency is examined and determine.
The frequency for the radiofrequency signal launched earth station simulator is examined and determine.
(2)RF pulse spectrum is examined and determine.
Have to the peak value in the respective ± 0.25MHz bandwidth centered on deviateing radio frequency channel nominal frequency ± 0.8MHz frequency
Effect radiant power is examined and determine.
Test condition is two kinds of mode of operations of Tacan and DME/P, respectively in -0.8MHz ,+0.8MHz, -2MHz ,+2MHz
Examined and determine.
(3)Impulse waveform is examined and determine
The pulse envelope of signal is examined and determine.Including pulse rise time, fall time and pulse width.
Test condition is two kinds of mode of operations of Tacan and DME/P.
(4)Pulse is examined and determine coding
Response pulse code is examined and determine.
Test condition is two kinds of mode of operations of Tacan and DME/P.During Tacan pattern, A/G X, A/G Y, A/ are separately positioned on
Examined and determine when A X, A/A Y;During DME/P patterns, examined and determine when being separately positioned on X, Y, W, Z.
(5)The coding calibrating of benchmark burst of pulses
Calibrating to primary standard group and prothetic group pregroup pulse code, including to the pulse spacing of X radio frequency channels and Y radio frequency channels, main base
The repetition rate of pregroup and prothetic group pregroup is examined and determine.
Test condition is, to primary standard group, to be examined and determine when being separately positioned on A/G X, A/G Y, A/A X, A/A Y;It is right
Prothetic group pregroup, examined and determine when being separately positioned on A/G X, A/G Y.
(6)Random filler pulse calibrating
Without request signal and do not launch it is main and auxiliary help reference pulse group under the conditions of, to random filler pulse logarithm purpose examine
It is fixed.
Test condition is that it is 500,2000,5000 and 8000 to set filling rate respectively.
(7)Examine and determine in orientation
The bearing signal of the simulation ground signal sent to equipment under test is examined and determine;
Test condition is that the scope for setting target bearing to be stated according to accredited instrument is set.
(8)Modulation degree is examined and determine
The modulation degree of transmission signal is examined and determine.
Test condition is that target modulation degree is respectively set into 10%, 20% and 39%.
(9)Distance calibrating
What equipment under test was sent examines and determine apart from delay of the reply pulse with receiving interrogation pulse;
Test condition is that the scope for setting target range to be stated according to accredited instrument is set.
(10)Peak power is examined and determine
Simulator is earthward tested with detecting platform simulation airborne equipment and sends interrogation pulse, and simulator is tested by ground
After showing that measured value, ECDC standard value are contrasted after calculating, so as to draw whether meet the requirements.
Brief description of the drawings:
Fig. 1 is the structured flowchart of the Tacan simulator metering device of the present invention;
Fig. 2 is the Tacan signal waveform that the device of the present invention collects.
Embodiment:
Herein below elaborates Figure of description is combined to the embodiment of the present invention:
Calibrating installation in the prior art is by analyzing unmodulated vision signal, so that it is determined that detection is set
It is standby whether qualified.And the actual signal of Tacan system is 950MHz ~ 1213MHz, only pass through the detection ability to radiofrequency signal
Whether qualified it is accurately positioned equipment under test;
Invention introduces radio-frequency technique, by NI RF vector signal generator PXI-5670 and NI RF vector signals point
Analyzer PXIe-5663(Including low-converter, digitizer and mixed frequency signal generator), realize directly collection earth station simulation
The radiofrequency signal that device sends and receives.
The workflow of Tacan calibration system be divided into reception and transmitting two kinds, receive process mainly receive bearing signal and
Distance measurement inquiring signal, this process are also to realize the calibration process of bearing signal;Emission process mainly launches ranging response letter
Number, by above-mentioned principle, ranging needs question-response, and location then only needs to receive and demodulate, and this process is mainly real
The calibration of existing distance measuring signal.
Referring to Fig. 1, the device of the invention is based on PXI bussing techniques, and Devices to test includes Tacan test equipment and microwave
Land test equipment, is the metering device of a synthesis, i.e. microwave landing metering device is designed as with Tacan simulator metering device
One.The metering device of Tacan simulator includes low noise power amplifier(PXI-5691)(Not shown in Fig. 1), RF up-converter
Device(PXI-5670), radio-frequency-down-converter(PXI-5601), arbitrary waveform signal generator, navigation signal processor, radio frequency work(
Rate amplifier and the part of private cable six.Wherein, navigation signal processor includes digitized instrument(PXI-5622)Believe with mixing
Number generator(PXI-5652).
Referring to Fig. 1, the radio-frequency power amplifier will input 5dBm pulse signals and be amplified to 500W, and the system includes defeated
Enter isolator, high-power RF amplifying circuit, circulator, output isolator, limiter, power supply and RF switch;Radiofrequency signal
After input isolator, into the high-power RF amplifying circuit, radio frequency amplifying circuit passes through after may amplify the signal to 500W
Cross output isolator and be input to circulator, signal is exported to limiter from the output end of circulator, enters back into RF switch afterwards
After export radiofrequency signal.The power supply provides voltage for high-power RF amplifying circuit and RF switch.
Described device reception signal process:Signal is by Tacan test equipment(Equipment under test)By cable connection to radio-frequency power
On the circulator of amplifier, circulator transmits a signal to clipping module, does not input a signal into isolator(The work of circulator
With being that signal is rotated to output in clockwise direction, not reverse transmission signal), then signal pass through RF switch, input
To low noise power amplifier(PXI-5691)Input, low noise power amplifier output end access radio frequency down-conversion(PXI-
5601)Input(RF IN), mixed frequency signal generator(PXI-5652)RF OUT terminals connection radio-frequency-down-converter LO
IN ends, for providing local oscillator parameter, the output end IF OUT of radio-frequency-down-converter(The principle of frequency conversion is:Input signal-mixing letter
Number=output signal)Access digitizer(PXI-5622)IF IN ends, one is connected between PXI-5652 and PXI-5622
Line synchro, it is synchronous for clock.
Signal emission process:Arbitrary waveform signal generator(PXI-5421)Signal is produced, is exported to radio-frequency-up-converter
Input, radio-frequency-up-converter itself carries local oscillator function, defeated by output end after signal frequency conversion by frequency conversion computing
Go out to the input of power amplifier(That is the isolator of radio-frequency power amplifier), then putting by radio-frequency power amplifier
Greatly, final signal is exported to equipment under test from circulator, completes the transmitting of signal.
The processing of signal is all carried out in navigation signal processor, and navigation signal processor includes mixed frequency signal
Device(PXI-5652)And digitizer(PXI-5622)Two boards.
Intermediate frequency distance measuring signal is mainly converted on radio-frequency channel by wherein described radio-frequency-up-converter, is believed for navigational range
Number transmitting;Radio-frequency-down-converter is used to the bearing signal of reception being converted to intermediate-frequency channel;Arbitrary waveform signal generator
For producing distance measuring signal(Distance measurement inquiring pulse), signal is amplified to 500W by radio-frequency power amplifier;At navigation signal
Device is managed to be used to handle the navigation signal Jing Guo frequency conversion, including azimuth-range signal.
For example, the calibration of distance signal(Reception and emission process):When have received distance measuring signal, fixing and prolonging according to agreement
When one constant time after, you can to start the transmitting of ranging transponder pulse, produced first by PXI-5421 AWGs
The pulse apart from transponder pulse, is then accessed upconverter, pulse signal modulation can be arrived Tacan by the module by raw one
Working frequency range 962MHz-1213MHz, Tacan system is sent an acknowledgement to by antenna or cable mode;So as to realize tower
The calibration of health system distance measuring signal.
In order to realize the measurement and calibration of above-mentioned Tacan ranging and location signal, the system is with the following method:
As shown in figure 1, the calibration of bearing signal(Receive process):Tacan signal is accessed by microwave cable first and calibrated
The low noise amplifier of system(PXI-5691), the module can remove unrelated signal, amplify useful signal, letter after filtering
Number access low-converter(PXIe-5601)Rf input terminal(RF IN), frequency can be 962MHz- by the module
1213MHz high-frequency signal downconverts to 50MHz intermediate-freuqncy signal, and the intermediate-freuqncy signal then is led into PXI- from IF OUT terminals
5622 input, PXI-5622 are digitizers, for handling intermediate frequency Tacan signal, pass through corresponding software in digitizer
The resolving of module, Tacan bearing signal is obtained, so as to realize the calibration of bearing signal.Fig. 2 is the Tacan signal that device collects
Waveform.
Software mainly uses virtual instrument and software and radio technique, is used cooperatively with hardware, completes navigation equipment middle-range
From the generation with bearing signal, collection, modulation, demodulation and data processing and storage.
Software section is included with lower module:
Level measurement module:For realizing that level magnitudes measure, that is, measure the voltage of measured signal.
Modulation measurement module:For being resolved to the modulation degree of bearing signal.
Azimuthal measurement module:In order to obtain azimuth information, it is necessary to phase between calculating benchmark group and envelope zero point phase
Difference, main and auxiliary benchmark burst of pulses is extracted from Tacan signal first, the zero point phase for then sub-electing envelope is obtained with
The orientation of Tacan.
Azimuth rate measurement module:Compare the module of Orientation differences speed, for cooling water of units of measurement time inner orientation signal
Rate of change.
Peak power detection module:Calibration system exports peak power, and measurement Tacan system can detect and measure peak value
The ability of power.
Distance-measurement module:For gathering, resolving and store range information.
Range transmission module:Produce distance signal, transmitting range pulse.
Waveform detection module:For detecting the waveform index of bearing signal, equivalent to the function of oscillograph.
Frequency detection module:Detect the change of CF signal frequency.
Pulse frequency spectrum module:The purity of frequency spectrum is resolved, equivalent to the function of frequency spectrograph.
Random filler pulse module:For producing random filler pulse, according to the random filling of agreement transmitting of Tacan signal
Pulse.
Other public modules:
Message sink coding and decoder module:
Message sink coding is mainly used in the compression of data, in favor of follow-up transmission.Common message sink coding algorithm includes
JPEG compression, zip(LZ77 and Huffman encoding algorithm combination), MP3 and MPEG-2 etc..
Channel coding and decoder module:
Different with message sink coding, channel coding can add or rewrite data position, in order to reduce noise in transmission
The influence come with attenuation band, obtains more preferable original transmission signal after decoding.
Examples detailed above is used for illustrating the present invention, rather than is limited.In the claims of the present invention
It is interior, it is any that modifications of the present invention is both fallen within protection scope of the present invention.