CN101702266B - Double station approach guidance positioning system and application - Google Patents

Abstract

The invention discloses a double station approach guidance positioning system which comprises an onboard subsystem and a ship-borne subsystem; the ship-borne subsystem comprises a primary beacon station and a secondary beacon station; the primary beacon station mainly consists of a precision interval clock, a timing synchronous beacon generator, a local oscillator, a double channel base band processing unit, a signal modulating circuit, a transmitter and the like; the onboard subsystem consists of a double channel front end receiving unit, a carrier wave phase difference detecting unit, a relative self time difference detecting unit, a precision distance measuring unit, a Doppler frequency shift measuring unit, and a positioning data processing unit. The inventive system applies precision distance measuring, Doppler frequency shift measuring, relative self time difference and carrier wave phase difference measuring technologies comprehensively, and mixes with proximate parallel to approach guidance law, thus realizing approach tracking and positioning to a ship-carrying aircraft, and initially providing the basic framework for realizing gliding angle feedback and control by the Doppler frequency shift under the conditions that the aircraft carrier speed and the gliding angle maintain unvaried.

Description

Double station approach guidance positioning system and application

Technical field:

The invention belongs to the radio tracking positioning field, be specifically related to a kind of fully utilize precise distance measurement, Doppler shift measurement, relative time error and carrier wave mutually technology such as difference measurements realize that carrier-borne aircraft enters two system of standing firm of nearly downslide guiding.

Background technology:

Under new military revolution condition, will aircraft carrier in the new military strategy of each aircraft carrier country be considered as the force at the core of naval, and the update of aircraft carrier classified as military technology develops and the transition strategy in important step.

According to the planning of U.S. army, the 4th generation aircraft carrier will equip unmanned opportunity of combat.The result of Primary Study shows that carrier-borne unmanned opportunity of combat will have following tactics to require when warship:

1, touches the warship bearing accuracy and want high.Owing to be that nobody controls, for guaranteeing accurately to touch warship, guide bearing accuracy, the measuring accuracy of particularly touching the warship stage will have higher requirement, and at present, USN requires the measuring error of carrier-borne aircraft on level and vertical plane less than 15 centimetres.

2, standby control is wanted continuously with the two stage convergence process of coupling of marching into the arena.And have the people drive opportunity of combat the warship process different, operation characteristic from unmanned plane, the transient process that traces into the flight path control when entering the downslide window and realizing near coupling from the voyage in blank pipe district standby control stage must be continuous, this is just needing the warship guidance system should implement the Coupling Control of marching into the arena, and can finish the standby course line again and follow the tracks of guiding.

3, advance nearly downslide guiding tracing process and want level and smooth.The flight-deck that modern aircraft carrier is being used for warship all be designed to and the aircraft carrier axis between an outside angle is arranged because aircraft carrier constantly advances forward, cause deck runway to be fallen along with the aircraft carrier motion constantly to the right front translation.When advancing closely knocking into the back warship, only is to follow the tracks of guiding in vertical plane as carrier-borne aircraft, promptly directly along the direction downglide motion of aircraft carrier navigation, will make that the design of automatic operational order is complicated, or even and difficulty.

With existing state-of-art with the 4th generation aircraft carrier the tactics demand compare, existing carrier-borne aircraft based on Radar Technology warship guiding system and is had following several big defective:

The one, observing and controlling process complexity.Whole warship bootup process is the collaborative observing and controlling process of a multisystem, need by air traffic control radar carrier-borne aircraft to be directed to the downslide window earlier, implement to march into the arena coupling by instrument landing system (ILS) then, do the guiding of gliding by accurate director radar again, finally do precision measurement by devices such as laser measurements touching the warship stage.

The 2nd, bearing accuracy is limited.Not only want the caused displacement of moving of modifying factor warship body in the warship stage of touching of warship guiding, but also need overcome the stern air-flow, so to touch the accurate measurement capability in warship stage be very important the disturbing influence that glide paths produced.And, can not after the data destination node, do any significant measurement based on the downslide director radar system of beam scanning technology, therefore need precision measurement apparatus such as configuration laser range finder.And owing to there is the scanning motion of antenna itself, deck motion compensation and estimate relative complex.

The 3rd, can't realize multimachine observing and controlling simultaneously.Existing shipborne radar guidance system is based on the work of warship face derived data mode, and under warship face derivation mode, the location survey data must send airborne equipment to by the reliable coding data chainning.Existing U.S. army research report shows: the naval vessel can cause degree of stability to reduce to the transmission delay of the signal of aircraft.

Therefore, existing carrier-borne aircraft guidance system based on Radar Technology is still a kind of technical equipment in mechanization epoch, the technical development of information age presses for further exploratory development can be with advanced technical know-how in the present age, more simple technical method and more economic working method realization aircraft carrier warship observing and controlling guiding relatively, with the operation and the viability of further raising aircraft carrier.

The formulation of existing microwave landing standard is mainly finished in the seventies in last century, also prematurity of multistation localization method and correlation technique at that time.With present state-of-art, with automatic the warship guidance system of multistation location technology structure should be when existing system such as first-harmonic bundle scanning microwave landing more advanced and comprehensive, the widespread use of GPS positioning system bright from the principle present to can directly utilize multistation integrated positioning system realization carrier-borne aircraft automatic the epoch of warship.More more flexible when the intrinsic structure of multistation location system uses it than radar system, on design concept, should be able to realize more function.

Obviously, and compare based on the radar of beam scanning technology, based on the multistation location technology the warship guidance system have plurality of advantages, but real Project Realization also has certain difficulty, for example the placement issue of numerous websites.Realize that as how minimum website it is problem demanding prompt solution that biplane advances the near orientation guiding.

Summary of the invention:

Deficiency at the prior art existence, a kind of two system of standing firm that are applicable to the carrier-borne aircraft approach guidance stage have been the objective of the invention is to provide, it is by integrated application precise distance measurement, Doppler shift measurement, relative time error and carrier wave technology such as difference measurements mutually, and it is near parallel near guidance law by being integrated into, realized the close tracking that advances of carrier-borne aircraft is located, also tentatively provided simultaneously under the condition of aircraft carrier speed and downslide unchanged view angle, by the basic framework of monitoring Doppler frequency difference realization the gliding angle FEEDBACK CONTROL.

The objective of the invention is to be achieved through the following technical solutions.

Whole double station approach guidance positioning system is drawn together On-Board Subsystem and carrier-borne subsystem two large divisions.

Carrier-borne subsystem mainly comprises two sync beacon sending stations, and the beaconing station of wherein bearing the precise distance measurement task is designated as main website, and another is secondary station.Carrier-borne beaconing station mainly is made up of precision interval clock, beacon generator, local oscillator, binary channels baseband processing unit, modulation circuit and transmitter etc.Carrier-borne beaconing station also can send running parameter information such as the headway, deck motion state of aircraft carrier.Described local oscillator produces the local reference signal source; Regularly the sync beacon generator is measured needed refresh rate fixed cycle ground to baseband processing unit transmission trigger pip by advancing nearly downslide under the control of precision interval clock; When generating beacon signal, the digital pulse signal that the binary channels Base Band Unit will contain the aircraft carrier aeronautical data by encoding on the one hand is sent to secondary station transmitter, then includes the required signals such as pseudo-random code of precise distance measurement on the other hand in the baseband signal that is sent to the main website transmitter; The signal modulation is converted to simulating signal with digital pulse signal, and transmitter carrier is modulated;

Described On-Board Subsystem is mainly by binary channels front end receiving element, carrier wave phase difference detection unit, formed from time difference detecting unit, precise distance measurement unit, Doppler shift measurement unit and airborne locator data processing unit; The binary channels receiving front-end receives the pulse signal from two beaconing stations simultaneously, and downconverts to after the intermediate-freuqncy signal and two paths of signals to be sent to the carrier wave phase difference detection unit simultaneously respectively and from time difference detecting unit; Precise distance measurement unit and Doppler shift measurement unit only need one road input signal; Receiving front-end also will be delivered to data processing unit after the signal decoding demodulation that includes operational data information from the pair station simultaneously; The horizontal departure that airborne locator data processing unit obtains measuring and calculating, radial distance, downslide visual angle, gliding angle and Doppler frequency difference export the flight TT﹠C system to.

For safety, the various information that On-Board Subsystem obtains also can come from the data chainning that fixed cycle receiving ship face TT﹠C system sends information except coming from the information that carrier-borne subsystem sends.

For realizing the orientation control in the surface level, carrier-borne aircraft airborne the warship guidance system be by rate-aided signal that carrier-borne two stations are sent relatively from the time difference and carrier wave difference measurements mutually, and utilize the precise distance measurement unit to measure relative radial distance r between warship face main website and carrier-borne aircraft ₀Obtain the alignment deviation value.

In vertical plane, airborne warship guidance system is accused that carrier-borne aircraft is followed and is parallelly advanced warship near guidance law and glide, and utilizes: (1) carrier-borne the parameters such as aircraft carrier headway that send by data chainning of warship guiding TT﹠C system; (2) the carrier-borne aircraft flying speed that sends of airborne sensor; (3) airborne the real-time measurement of warship guidance system to Doppler shift between machine-warship; (4) and to the precision measurement of relative radial distance.And can directly calculate by the fusion treatment of downslide proportionate relationship: the relative downslide visual angle between (1) machine-warship with the Doppler shift relation; (2) carrier-borne aircraft advances nearly gliding angle; (3) can also obtain downslide time and distance of glide by the measuring and calculating of trigonometric function relation simultaneously.

Specifically may further comprise the steps:

Step 1, warship face two beaconing stations are laid in aircraft carrier in contour symmetry on the surface level and enter slippery runway both sides under the warship, and in the ordinary course of things, and it is vertical that base direction and carrier-borne aircraft advance nearly gliding direction.

Step 2, when carrier-borne aircraft begins to enter near downslide during the stage, will advance nearly downslide by following downslide proportionate relationship:

$\frac{V_F}{\sin {\mathrm{\φ}}_0}=\frac{V_H}{\sin ({\mathrm{\φ}}_0-{\mathrm{\φ}}_k)}---\left(1\right)$

In the formula: V _HSpeed for aircraft carrier; V _FSpeed for aircraft; φ ₀Being the downslide visual angle, is a steady state value; φ _kIt is the instantaneous gliding angle of carrier-borne aircraft.

Step 3, the measuring and calculating of surface level alignment deviation.

The time difference detecting unit of airborne warship observing and controlling guidance system adopts from the method for time difference measurement and measures mistiming Δ t between the beacon signal that is sent from warship face two symmetrical beaconing stations.

Simultaneously, airborne warship guiding TT﹠C system obtains differing Δ θ from the carrier wave between the beacon signal of warship face two symmetrical beaconing stations by the carrier wave phase difference detection unit.

In addition, airborne warship guiding TT﹠C system also utilizes the precise distance measurement unit to measure relative radial distance r between warship face main website and carrier-borne aircraft ₀

The locator data processing unit of airborne warship guidance system is calculated as follows the alignment deviation on the output surface level:

$\mathrm{\&Delta;x}=\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0}{2a}\mathrm{\&Delta;r}---\left(2\right)$

In the formula: 2a is the base length between two beaconing stations; Δ r is the path difference between the two station radial distances, and has:

$\mathrm{\&Delta;r}=r_2-{\mathrm{<figure-callout\; id="1"\; label="r"\; filenames="H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_1=\mathrm{\&lambda;}[int\left(\frac{\mathrm{c\&Delta;t}}{\mathrm{\&lambda;}}\right)+\frac{\mathrm{\&Delta;\&theta;}}{2\mathrm{\&pi;}}]---\left(3\right)$

In the formula: Δ θ=Δ θ ₂-Δ θ ₁, the carrier wave measured for airborne end differs.

The information that step 4, airborne warship guidance system send by carrier-borne subsystem and the regular receiving ship face of data chainning TT﹠C system is comprising the required aircraft carrier headway V of location measuring and calculating _HDeng parameter, be used to the into measuring and calculating of nearly location.

Airborne the Doppler shift measurement unit of warship guidance system obtains Doppler shift f between warship-machine by the beacon signal detection to carrier-borne beacon main website _d, and by the homing principle, the equation that calculates the Doppler shift between warship-machine is:

$f_d=\frac{1}{\mathrm{\&lambda;}}[V_{F}cso\mathrm{\&beta;}-V_{H}cos{\mathrm{\&phi;}}_0]---\left(4\right)$

In the formula: β=φ ₀-φ _kAngle of lead for carrier-borne aircraft.

The data processing unit of step 5, airborne warship guidance system is calculated as follows the downslide visual angle:

${\cos \mathrm{\&phi;}}_0=\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}---\left(5\right)$

The data processing unit of step 6, airborne warship guidance system is calculated as follows gliding angle:

${\mathrm{\&phi;}}_k={\mathrm{\&phi;}}_0-\mathrm{\&beta;}---\left(6\right)$

$={\cos }^{-1}\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]-{\sin }^{-1}\left\{\frac{V_H}{V_F}\sqrt{1-{\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]}^2}\right\}$

The data processing unit of step 7, airborne warship guidance system is calculated as follows current distance of glide:

$l=\frac{\sin {\mathrm{\&phi;}}_0}{\sin {\mathrm{\&phi;}}_k}{r}_0---\left(7\right)$

And be calculated as follows the current downslide time:

$t=\frac{l}{V_F}=\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\sin {\mathrm{\&phi;}}_0}{V_F\sin {\mathrm{\&phi;}}_k}---\left(8\right)$

Step 8: under the situation of not change, change the FEEDBACK CONTROL that can realize based on Doppler frequency difference to gliding angle at the supposition headway of aircraft carrier and downslide visual angle.

Be located at carrier aircraft speed when constant, only the Doppler frequency difference Δ f that is produced by the gliding angle change _{D φ k}:

λΔf _dφk＝V _F0cos(β ₀+Δφ _k)-V _F0cosβ ₀ (9)

Wherein: Δ φ _kIt is the gliding angle variable quantity.

Calculating what be used for FEEDBACK CONTROL by following formula is the gliding angle variable quantity of independent variable with the Doppler shift variable quantity:

${\mathrm{\&Delta;\&phi;}}_k={\cos }^{-1}\left[\frac{\mathrm{\&lambda;}}{V_{F0}}({\mathrm{<figure-callout\; id="0"\; label="f\; d"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">f</figure-callout>}}_d+{\mathrm{\&Delta;f}}_{\mathrm{d\&phi;k}})\right]-{\mathrm{\&beta;}}_0---\left(10\right)$

In the formula: f _D0Be carrier-borne aircraft in accordance with regulations gliding angle advance Doppler shift value when near.

The present invention brings following beneficial effect:

(1) the double station approach guidance system that merges the Doppler shift measurement technology had both embodied that multistation integrated positioning guidance system had need not complicated antenna feeder and servo-control system, can realize aerial derived data, help catching the best touches series of advantages such as warship opportunity, avoid the many defectives of cloth station quantity again, will make the system of systems configuration more simplify thus.

(2) have unidirectional information transfer capability, promoted whole guidance system security and reliability.

(3) the Doppler frequency difference value between adjacent two measured node can be control system provides adaptively correcting required feedback control signal, can realize that changing response with Doppler frequency difference is the system compensation control mode of benchmark.

Description of drawings:

Fig. 1: the theory diagram of carrier-borne subsystem.

Fig. 2: the basic framework figure of On-Board Subsystem.

Fig. 3: the coordinate system of two stations symmetrical measurement and cloth station configuration figure.

Fig. 4: the alignment deviation figure on lateral separation.

Fig. 5: advance warship downslide schematic diagram in the vertical plane.

Fig. 6: certain downslide triangle synoptic diagram in a flash.

Fig. 7: based on the feedback control structure block diagram of Doppler frequency difference.

Embodiment

How further specify the present invention below in conjunction with accompanying drawing 1-Fig. 7 realizes.

A kind of comprehensive time difference, differ, the double station approach guidance system of frequency displacement, distance measurement technique.Fig. 1 has provided the theory diagram of carrier-borne subsystem; Fig. 2 has provided the basic framework of On-Board Subsystem; Fig. 3 has provided the coordinate system and the cloth station configuration of two stations symmetrical measurement; Fig. 4 is the alignment deviation on lateral separation; Fig. 5 advances warship downslide schematic diagram in the vertical plane; Fig. 6 has described certain downslide triangle in a flash; Fig. 7 is based on the feedback control structure block diagram of Doppler frequency difference.

1, system framework

Whole positioning system comprises On-Board Subsystem and carrier-borne subsystem two large divisions.

As shown in Figure 1, carrier-borne subsystem mainly comprises two beacon sending stations, and the beaconing station of wherein bearing carrier-borne aircraft precise distance measurement task is called as main website, and another beaconing station of bearing information transmission task is secondary station.Carrier-borne beaconing station mainly is made up of precision interval clock, beacon generator, local oscillator, binary channels baseband processing unit, modulation circuit and transmitter etc.Local oscillator produces the local reference signal source; Regularly the sync beacon generator sends trigger pip by what advance that nearly downslide measures needed refresh rate fixed cycle to baseband processing unit under the control of precision interval clock; When generating beacon signal, the digital pulse signal that the binary channels Base Band Unit can will contain aircraft carrier headway, deck motion state or the like data by encoding on the one hand is sent to secondary station transmitter, then includes the required signals such as pseudo-random code of precise distance measurement on the other hand in the baseband signal that is sent to the main website transmitter; The signal modulation is converted to simulating signal with digital pulse signal, and transmitter carrier is modulated.

On-Board Subsystem mainly is made up of binary channels front end receiving element, carrier wave phase difference detection unit, relative time error detecting unit, precise distance measurement unit, Doppler shift measurement unit and locator data processing unit as shown in Figure 2.The binary channels receiving front-end receives the pulse signal from two beaconing stations simultaneously, and downconverts to after the intermediate-freuqncy signal and two paths of signals to be sent to the carrier wave phase difference detection unit simultaneously respectively and from time difference detecting unit; Precise distance measurement unit and Doppler shift measurement unit only need one road input signal; Receiving front-end also will be delivered to data processing unit after the signal decoding demodulation that includes operational data information from the pair station simultaneously; The horizontal departure that airborne locator data processing unit obtains measuring and calculating, radial distance, downslide visual angle, gliding angle and Doppler frequency difference export the flight TT﹠C system to.In order to ensure safety, also utilize data chainning to transmit various information in addition.

Approach guidance positioning system is achieved through the following technical solutions location survey:

For realizing the orientation control in the surface level, carrier-borne aircraft airborne the warship guidance system be by rate-aided signal that carrier-borne two stations are sent relatively from the time difference and carrier wave difference measurements mutually, and utilize the precise distance measurement unit to measure relative radial distance r between warship face main website and carrier-borne aircraft ₀Obtain the alignment deviation value.

In vertical plane, airborne warship guidance system is accused that carrier-borne aircraft is followed and is parallelly advanced warship near guidance law and glide, and utilizes: (1) carrier-borne the parameters such as aircraft carrier headway that send by data chainning of warship guiding TT﹠C system; (2) the carrier-borne aircraft flying speed that sends of airborne sensor; (3) airborne the real-time measurement of warship guidance system to Doppler shift between machine-warship; (4) and to the precision measurement of relative radial distance.And can directly calculate by the fusion treatment of downslide proportionate relationship: the relative downslide visual angle between (1) machine-warship with the Doppler shift relation; (2) carrier-borne aircraft advances nearly gliding angle; (3) the remaining downslide time of measuring and calculating; (4) measuring and calculating distance of glide.

2, the centering in the surface level is measured

(1) key concept

Symmetrical measurement is a kind of not only simply but also effective metering system, can realize that orientation controls.Existing based on the time first-harmonic speed scanning a work characteristics of microwave landing mode be exactly in surface level, to know whether line up with runway of aircraft, a kind of correction measurement process of utilizing symmetry principle that in fact Here it is by scanning.

The another kind of directional guide method of equal value mutually with flat scanning is two stations symmetrical measurements.When the two station of application symmetrical measurement modes realize directional guide, two measuring station symmetries can be placed on the both sides of runway, by the range difference between two stations therewith of aircraft relatively, can determine whether aircraft has departed from runway heading in measurement plane, and depart from which side.

Compare with the beam scanning technology, the principal advantages of two stations symmetrical measurement is exactly simple.Fig. 3 has provided the basic cloth station form of two stations symmetrical measurement, and among the figure: T is a measured target; Runway is positioned at the y direction of principal axis; A is the lateral separation between website and true origin, and the base length between two stations is 2a; r ₁And r ₂It is the radial distance between two websites and the target.Under the mode based on distance time difference symmetrical measurement, the fundamental measurement formula is:

Δr＝cΔt＝r ₂-r ₁ (1)

In the formula: Δ t is the time difference between two stations; C is the light velocity.

(2) the shortest base length

Symmetrical measurement has many advantages, but for time difference measurement, when being tending towards the process of centering just just the time difference be tending towards minimum at interval, at this moment, it is uncertain that the minimum resolution of time difference measurement circuit itself will make measurement result sink into, and the measuring accuracy at centering place is often clearly stipulated, in order to realize the technical requirement of precision measurement, can avoid the influence of minimum resolution again, just must rationally determine the length of baseline.

The process that centering is measured is exactly that the Sustainable Control adjusting goes to zero Δ r, yet on actual engineering design, the precision of time difference measurement will be subjected to the influence of minimum resolution, establish Δ r _pBe minimum time difference resolution ax/t _pPairing path length difference, then work as | r ₂-r ₁|≤Δ r _pThe time given measured value will be uncertain.

Δ r _pGiven in the critical value of measuring uncertainty scope in the radial direction.In fact, what the symmetrical directional guide in two stations limited is the deviation of target in the base length direction, is the accuracy that guarantees directional guide, and we must consider the boundary value by the caused uncertain measuring error in the base length direction of minimum time difference resolution.

For the purpose of clear, three-dimensional picture shown in Figure 3 is reduced to as shown in Figure 4 two dimensional surface vertical view, and supposition only exists by the caused measuring error of minimum time difference resolution, and only consider situation at the center origin place, in fact, the uncertain error that is only produced by minimum time difference resolution when the centering state is only maximum.

Obviously, uncertain for fear of occurring on measuring, the path length difference between two stations must be greater than the dividing value Δ r corresponding to minimum time difference resolution _pSo, can list following formula by the simple geometric relation:

$\sqrt{{(a+{\mathrm{\&Delta;x}}_p)}^2+r_y^2}-\sqrt{{(a-\mathrm{\&Delta;}{x}_p)}^2+{\mathrm{<figure-callout\; id="2"\; label="r\; y"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">r</figure-callout>}}_y^{}}\&GreaterEqual;{\mathrm{\&Delta;r}}_p---\left(2\right)$

Wherein: Δ x _pFor on the x direction of principal axis corresponding to minimum time difference resolution ax/t _pThe critical value of uncertain measuring error scope.

Formula (2) can be write as following form:

$\sqrt{(a^2+r_y^2)+(\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="x\; p"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">x</figure-callout>}}_p^{}+2a{\mathrm{\&Delta;x}}_p)}-\sqrt{(a^2+r_y^2)+({\mathrm{\&Delta;x}}_p^2-2a{\mathrm{\&Delta;x}}_p)}\&GreaterEqual;{\mathrm{\&Delta;r}}_p---\left(3\right)$

Have after using approximate formula:

$[1+\frac{{\mathrm{\&Delta;<figure-callout\; id="2"\; label="x\; p"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">x</figure-callout>}}_p^{}+2a{\mathrm{\&Delta;x}}_p}{2(a^2+r_y^2)}]-[1+\frac{{\mathrm{\&Delta;x}}_p^2-2a\mathrm{\&Delta;}{x}_p}{2(a^2+r_y^2)}]\&GreaterEqual;\frac{{\mathrm{\&Delta;r}}_p}{\sqrt{a^2+r_y^2}}---\left(4\right)$

Can obtain thus to avoiding, the estimation formulas of short base length because of minimum time difference resolution measurement is occurred uncertainly:

$a\&GreaterEqual;\frac{{\mathrm{<figure-callout\; id="2"\; label="r\; y"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">r</figure-callout>}}_y}{2}\frac{{\mathrm{\&Delta;r}}_p}{{\mathrm{\&Delta;x}}_p}---\left(5\right)$

Formula (5) can also be expressed as:

${\mathrm{\&Delta;x}}_p=\frac{r_y}{2a}{\mathrm{\&Delta;r}}_p---\left(6\right)$

The meaning of following formula is: corresponding to a uncertain measurement range Δ r of path length difference radially _p, on the x direction of principal axis, have a corresponding uncertain region Δ x _p, and have the scale factor of approximately constant between the two

Can make uncertain deviation on the x direction of principal axis less than the design load of regulation by adjusting base length in theory.Otherwise, at the minimum uncertain measuring error range delta x that has stipulated to be allowed on the lateral separation _pAfterwards, can through type (6) approximate determine the time difference measurement system the minimum resolution that should have.

In fact, can obtain by theory of errors and the proportionate relationship formula that is of universal significance of formula (6) all fours:

${\mathrm{\&sigma;}}_x=\frac{r}{2a}{\mathrm{\&sigma;}}_r---\left(7\right)$

In the formula: σ _xIt is the measuring error root-mean-square value on the x axle; σ _rBe about the measuring error root-mean-square value on the distance radially.

(3) alignment deviation the time/differ measuring and calculating

For improving the precision that centering is measured, not only adopted in the engineering design from the time difference measurement technology, also use carrier wave simultaneously and differed measuring technique.

Adopt and the identical mathematical method of minimum time difference resolution critical value analysis, can be able to from carrier aircraft to the radial distance r the warship face main website ₀Alignment deviation computing formula for parameter:

$\mathrm{\&Delta;x}=\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0}{2a}\mathrm{\&Delta;r}---\left(8\right)$

The measuring and by rough determining of unit when at first, path difference Δ r can survey by airborne end from time difference Δ t:

Δr＝cΔt＝c(Δt ₂-Δt ₁) (9)

The unidirectional range finding formula between carrier-borne aircraft and beaconing station based on the metering system of carrier phase is:

${\mathrm{<figure-callout\; id="1"\; label="r"\; filenames="H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_1=c{\mathrm{\&Delta;<figure-callout\; id="1"\; label="t"\; filenames="H2009101980538E00032.png"\; state="\{\{state\}\}">t</figure-callout>}}_1=\mathrm{\&lambda;}({\mathrm{<figure-callout\; id="0"\; label="N"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">N</figure-callout>}}_0+\frac{\mathrm{\&Delta;}{\mathrm{\&theta;}}_1}{2\mathrm{\&pi;}})---\left(10\right)$

${\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">r</figure-callout>}}_2=c{\mathrm{\&Delta;<figure-callout\; id="2"\; label="t"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">t</figure-callout>}}_2=\mathrm{\&lambda;}[{\mathrm{<figure-callout\; id="0"\; label="N"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">N</figure-callout>}}_0+\mathrm{int}\left(\frac{\mathrm{\&Delta;r}}{\mathrm{\&lambda;}}\right)+\frac{{\mathrm{\&Delta;\&theta;}}_2}{2\mathrm{\&pi;}}]---\left(11\right)$

In the formula: N ₀Be the complete cycle number; Δ θ ₁With Δ θ ₂Be carrier phase.

Based on from time difference measurement and the carrier wave path difference formula of difference measurements mutually:

$\mathrm{\&Delta;r}=r_2-{\mathrm{<figure-callout\; id="1"\; label="r"\; filenames="H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_1=\mathrm{\&lambda;}[\mathrm{int}\left(\frac{\mathrm{c\&Delta;t}}{\mathrm{\&lambda;}}\right)+\frac{\mathrm{\&Delta;\&theta;}}{2\mathrm{\&pi;}}]---\left(12\right)$

In the formula: Δ θ=Δ θ ₂-Δ θ ₁The carrier wave measured for airborne end differs.

3, the approach guidance in the vertical plane

(1) parallel near guidance law

The general rule that carrier-borne aircraft warship be aircraft carrier against the wind, the aircraft warship that knocking into the back.For realizing the maneuver tracking to the aircraft carrier that moves along a straight line, carrier-borne aircraft must glide according to certain guidance law.

Existing research is verified: proportional guidance law is under a kind of, the unfettered situation of control energy not motor-driven in target in itself, has the optimal guidance rule of zero miss distance.A special case of proportional guidance law is exactly a constant-bearing course, this guidance method can make from the tracker see that the direction of visual lines of target is constant, also be that sight line is parallel to each other all the time in the flight course.Because it can guarantee that tracker and target intersect, and can make the flight path of tracker more straight again, thereby be to be used for the first-selected guidance law that aircraft carrier warship.

Parallel principle of work near guidance law as shown in Figure 5, aircraft will promptly keep making aircraft to the constant rule of the direction of visual lines of aircraft carrier by parallel close control rule during downslide, realizes gliding warship.

The analytic process of existing guidance law all is to set about from the Equation of Relative Motion with Small between tracker and the target, given more complicated as a result.By contrast, because known conditions is more, it will be more simple and direct directly setting about carrying out analysis result from its relative motion geometric relationship for aircraft carrier warship, utilize simple geometric relation, can provide the proportionate relationship formula of getting in touch between a simple and direct description gliding speed and the gliding angle.

As shown in Figure 6, suppose aircraft by the constant-bearing course warship that gliding, glide certain in a flash, aircraft is positioned at P _kThe point place, this moment, the speed of aircraft carrier was V _H, the flying speed of carrier-borne aircraft is V _Fφ among the figure ₀Be the downslide visual angle; φ _kIt is gliding angle.

Be located at and experienced after the minimum time interval Δ t, the travelled distance of Δ d of aircraft carrier: Δ d=V _HΔ t.The distance of Δ l and carrier-borne aircraft has glided: Δ l=V _FΔ t.By sine, from triangle Δ P _kCan obtain following downslide ratio relational expression among the MG:

$\frac{V_F}{\sin {\mathrm{\&phi;}}_0}=\frac{V_H}{\sin ({\mathrm{\&phi;}}_0-{\mathrm{\&phi;}}_k)}---\left(13\right)$

(2) the Doppler shift equation between machine-warship

By the kinematic relation between carrier-borne aircraft-aircraft carrier, can list following Doppler shift equation:

$f_d=\frac{1}{\mathrm{\&lambda;}}[V_{F}cos\mathrm{\&beta;}-V_{H}cos{\mathrm{\&phi;}}_0]---\left(14\right)$

In the formula: β is an angle of lead, and has according to inside and outside angular dependence: β=φ ₀-φ _kλ is a wavelength.

(3) basic measure formula

A, downslide visual angle

Through the conversion arrangement, downslide proportional guidance relational expression (and the Doppler shift equation between carrier-borne aircraft-aircraft carrier can be written as:

V _Fsinβ＝V _Hsinφ ₀ (15)

V _Fcosβ＝λf _d+V _Hcosφ ₀ (16)

With addition behind the above-mentioned two formula both sides square, can obtain:

${\mathrm{<figure-callout\; id="2"\; label="V\; F"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">V</figure-callout>}}_F^{}={\mathrm{<figure-callout\; id="2"\; label="V\; H"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">V</figure-callout>}}_H^{}+{\left(\mathrm{\&lambda;}{f}_d\right)}^2+2\mathrm{\&lambda;}{f}_d{V}_H\cos {\mathrm{\&phi;}}_0---\left(17\right)$

Therefrom can solve the measure formula at downslide visual angle:

${\cos \mathrm{\&phi;}}_0=\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}---\left(18\right)$

B, gliding angle

With formula (18) substitution downslide proportional guidance relational expression, can obtain the computing formula of angle of lead:

$\sin \mathrm{\&beta;}=\frac{V_H}{V_F}\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="H2009101980538E00032.png,H2009101980538E00051.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2{\mathrm{\&phi;}}_0}---\left(19\right)$

$=\frac{V_H}{V_F}\sqrt{1-{\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]}^2}$

Can try to achieve gliding angle according to the relation between angle of lead and the gliding angle:

${\mathrm{\&phi;}}_k={\mathrm{\&phi;}}_0-\mathrm{\&beta;}---\left(20\right)$

$={\cos }^{-1}\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]-{\sin }^{-1}\left\{\frac{V_H}{V_F}\sqrt{1-{\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]}^2}\right\}$

C, distance of glide and time

After recording the angle parameter, utilize radial distance can try to achieve current distance of glide:

$l=\frac{{\sin \mathrm{\&phi;}}_0}{{\sin \mathrm{\&phi;}}_k}{r}_0---\left(21\right)$

And obtain the current downslide time by following formula:

$t=\frac{l}{V_F}=\frac{{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">r</figure-callout>}}_0\sin {\mathrm{\&phi;}}_0}{V_F\sin {\mathrm{\&phi;}}_k}---\left(22\right)$

4, based on the gliding angle FEEDBACK CONTROL of Doppler frequency difference

(1) general introduction

Doppler shift equation of analysis between machine-warship is shown, follow in the process that guidance law advances nearly downslide at carrier-borne aircraft, movement velocity as carrier-borne aircraft and aircraft carrier, and various parameters such as downslide visual angle and gliding angle do not change, measured Doppler shift all will keep identical on the sliding position of opinion then in office, and promptly the Doppler frequency difference on two adjacent measured node should go to zero.In case and Doppler shift has departed from steady state (SS), just mean that then change may take place various parameters.So, just the Doppler frequency difference between adjacent measured node can the feedback compensation signal of warship guiding TT﹠C system as carrier-borne aircraft, and flight control system just can be carried out FEEDBACK CONTROL by the Doppler frequency difference variation that airborne warship guidance system is provided by direct monitoring.

(2) the Doppler's variable quantity that only produces by the carrier aircraft velocity variations

If V _F0Be the carrier-borne aircraft gliding speed of normally advancing nearly downslide system index defined for finishing, as the carrier aircraft speed of current actual measurement be: V _F=V _F0+ Δ V _F, then directly solve only by carrier aircraft speed fluctuation Δ V by the Doppler shift equation _fThe Doppler's variable quantity that is produced is:

λΔf _dv＝(V _F0+ΔV _F)cosβ ₀-V _F0cosβ ₀ (23)

＝ΔV _Fcosβ ₀

Wherein: β ₀It is angle of lead by the system index defined.

(3) only change the Doppler's variable quantity that produces by gliding angle

Under the situation of downslide unchanged view angle, as gliding angle generation Δ φ _kDuring variation, by the relation at interior exterior angle: φ ₀=φ _k+ β can obtain the change value corresponding to angle of lead:

Δβ＝|Δφ _k| (24)

When carrier aircraft speed was constant, only the Doppler frequency difference that is produced by the gliding angle change was:

λΔf _dφk＝V _F0cos(β ₀+Δφ _k)-V _F0cosβ ₀ (25)

Also can solve with the Doppler shift variable quantity is the function representation formula of the gliding angle variable quantity of independent variable:

$\mathrm{\&Delta;}{\mathrm{\&phi;}}_k={\cos }^{-1}\left[\frac{\mathrm{\&lambda;}}{V_{F0}}({\mathrm{<figure-callout\; id="0"\; label="f\; d"\; filenames="H2009101980538E00031.png,H2009101980538E00032.png"\; state="\{\{state\}\}">f</figure-callout>}}_d+\mathrm{\&Delta;}{f}_{\mathrm{d\&phi;k}})\right]-{\mathrm{\&beta;}}_0---\left(26\right)$

In the formula: f _D0It is the Doppler shift value of system index defined.

(4) approximate overlaying relation

All have under the situation of change in carrier aircraft gliding speed and gliding angle, by the Doppler frequency difference equation:

λΔf _d＝(V _F0+ΔV _F)cos(β ₀+Δφ _k)-V _F0cosβ ₀ (27)

Can derive:

${\mathrm{\&Delta;f}}_d={\mathrm{\&Delta;f}}_{\mathrm{dv}}+\mathrm{\&Delta;}{f}_{\mathrm{d\&phi;k}}+\frac{{\mathrm{\&Delta;}{f}_{\mathrm{dv}}\mathrm{\&Delta;f}}_{\mathrm{d\&phi;k}}}{f_{d0}}---\left(28\right)$

As the Doppler shift f under the steady state (SS) _D0Enough big, then being similar to has overlaying relation:

Δf _d≈Δf _dv+Δf _dφk (29)

(5) gliding angle feedback control structure figure

Fig. 7 has tentatively provided a kind of at the supposition headway of aircraft carrier and downslide visual angle under the situation of not change, change the basic structure framework that gliding angle is carried out FEEDBACK CONTROL based on Doppler frequency difference, at this moment, the variation that the airborne data processing unit that advances nearly guidance system is only exported gliding angle, the airborne locator data processing unit among the figure is the same unit in the block diagram shown in Figure 2.

Claims (10)

1. a double station approach guidance positioning system comprises On-Board Subsystem and carrier-borne subsystem, it is characterized in that:

Described carrier-borne subsystem is made up of two beaconing stations that send beacon message and transmission data message, and carrier-borne beaconing station is made up of precision interval clock, timing sync beacon generator, local oscillator, binary channels baseband processing unit, signal modulation circuit and transmitter;

Described local oscillator produces the local reference signal source; Regularly the sync beacon generator is measured needed refresh rate fixed cycle ground to baseband processing unit transmission trigger pip by advancing nearly downslide under the control of precision interval clock; When generating beacon signal, the digital pulse signal that the binary channels Base Band Unit will contain the aircraft carrier aeronautical data by encoding on the one hand is sent to secondary station transmitter, then includes the required signals such as pseudo-random code of precise distance measurement on the other hand in the baseband signal that is sent to the main website transmitter; The signal modulation is converted to simulating signal with digital pulse signal, and transmitter carrier is modulated;

Described On-Board Subsystem is by binary channels front end receiving element, carrier wave phase difference detection unit, formed from time difference detecting unit, precise distance measurement unit, Doppler shift measurement unit and airborne locator data processing unit; The binary channels receiving front-end receives the pulse signal from two beaconing stations simultaneously, and downconverts to after the intermediate-freuqncy signal and two paths of signals to be sent to the carrier wave phase difference detection unit simultaneously respectively and from time difference detecting unit; Precise distance measurement unit and Doppler shift measurement unit only need one road input signal; Receiving front-end also will be delivered to data processing unit after the signal decoding demodulation that includes operational data information from the pair station simultaneously; The horizontal departure that airborne locator data processing unit obtains measuring and calculating, radial distance, downslide visual angle, gliding angle and Doppler frequency difference export the flight TT﹠C system to.

2. double station approach guidance positioning system according to claim 1 is characterized in that: the various information that On-Board Subsystem obtains comes from the data chainning that fixed cycle receiving ship face TT﹠C system sends information, the information that perhaps comes from carrier-borne subsystem and sent.

3. double station approach guidance positioning system according to claim 1 is characterized in that: major and minor two beaconing stations of described warship face are laid in aircraft carrier in contour symmetry on the surface level and enter slippery runway both sides under the warship, and base direction and carrier-borne aircraft to advance nearly gliding direction vertical.

4. according to any described double station approach guidance positioning system of claim 1-3, it is characterized in that: carrier-borne aircraft begins to enter near downslide during the stage, will advance nearly downslide by following downslide proportionate relationship:

$\frac{V_F}{\sin {\mathrm{\&phi;}}_0}=\frac{V_H}{\sin ({\mathrm{\&phi;}}_0-{\mathrm{\&phi;}}_k)}---\left(1\right)$

In the formula: V _HSpeed for aircraft carrier; V _FSpeed for aircraft; φ ₀Being the downslide visual angle, is a steady state value; φ _kIt is the instantaneous gliding angle of carrier-borne aircraft.

5. according to any described double station approach guidance positioning system of claim 1-3, it is characterized in that: mistiming Δ t between the beacon signal that is sent from warship face two symmetrical beaconing stations is measured in adopting from the method for time difference measurement from time difference detecting unit of described On-Board Subsystem, obtain differing Δ θ by the carrier wave phase difference detection unit simultaneously, and utilize the precise distance measurement unit to measure relative radial distance r between warship face main website and carrier-borne aircraft from the carrier wave between the beacon signal of warship face two symmetrical beaconing stations ₀, the locator data processing unit of On-Board Subsystem is calculated as follows the alignment deviation on the output surface level:

$\mathrm{\&Delta;x}=\frac{r_0}{2a}\mathrm{\&Delta;r}---\left(2\right)$

In the formula: 2a is the base length between two beaconing stations; Δ r is the path difference between the two station radial distances, and has:

$\mathrm{\&Delta;r}=r_2-r_1=\mathrm{\&lambda;}[\mathrm{int}\left(\frac{\mathrm{c\&Delta;t}}{\mathrm{\&lambda;}}\right)+\frac{\mathrm{\&Delta;\&theta;}}{2\mathrm{\&pi;}}]---\left(3\right)$

In the formula: c is the light velocity; λ is a wavelength, Δ θ=Δ θ ₂-Δ θ ₁The carrier wave measured for airborne end differs.

6. double station approach guidance positioning system according to claim 1, it is characterized in that: the Doppler shift measurement unit of On-Board Subsystem, obtain Doppler shift between warship-machine by beacon signal detection to carrier-borne beacon main website, and, calculate the Doppler shift between warship-machine by the homing principle.

7. double station approach guidance positioning system according to claim 1 is characterized in that: the data processing unit of On-Board Subsystem is calculated as follows the downslide visual angle:

$\cos {\mathrm{\&phi;}}_0=\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}---\left(5\right)$

In the formula: λ is a wavelength.

8. double station approach guidance positioning system according to claim 1 is characterized in that: the data processing unit of On-Board Subsystem is calculated as follows gliding angle:

${\mathrm{\&phi;}}_k={\mathrm{\&phi;}}_0-\mathrm{\&beta;}$ (6)

$={\cos }^{-1}\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]-{\sin }^{-1}\left\{\frac{V_H}{V_F}\sqrt{1-{\left[\frac{V_F^2-V_H^2-{\left(\mathrm{\&lambda;}{f}_d\right)}^2}{2\mathrm{\&lambda;}{f}_d{V}_H}\right]}^2}\right\}$

In the formula: β is an angle of lead, and λ is a wavelength.

9. double station approach guidance positioning system according to claim 1 is characterized in that: the data processing unit of On-Board Subsystem is calculated as follows current distance of glide:

$l=\frac{\sin {\mathrm{\&phi;}}_0}{\sin {\mathrm{\&phi;}}_k}{r}_0---\left(7\right)$

And be calculated as follows the current downslide time:

$t=\frac{l}{V_F}=\frac{r_0\sin {\mathrm{\&phi;}}_0}{V_F\sin {\mathrm{\&phi;}}_k}.---\left(8\right)$

10. double station approach guidance positioning system according to claim 1 is characterized in that: under the situation of not change, change the FEEDBACK CONTROL that can realize gliding angle at the supposition headway of aircraft carrier and downslide visual angle based on Doppler frequency difference:

Be located at carrier aircraft speed when constant, only the Doppler frequency difference Δ f that is produced by the gliding angle change _{D φ k}:

λΔf _dφk＝V _F0cos(β ₀+Δφ _k)-V _F0cosβ ₀ (9)

Wherein: Δ φ _kIt is the gliding angle variable quantity;

Calculating what be used for FEEDBACK CONTROL by following formula is the gliding angle variable quantity of independent variable with the Doppler shift variable quantity:

${\mathrm{\&Delta;\&phi;}}_k={\cos }^{-1}\left[\frac{\mathrm{\&lambda;}}{V_{F0}}(f_{d0}+{\mathrm{\&Delta;f}}_{\mathrm{d\&phi;k}})\right]-{\mathrm{\&beta;}}_0---\left(10\right)$

In the formula: f _D0Be carrier-borne aircraft in accordance with regulations gliding angle advance Doppler shift value when near, β ₀Be angle of lead by the system index defined.

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