RU2620587C1 - Method of determining the coordinates of an aircraft relative to the flight strip - Google Patents

Abstract

FIELD: aviation.

SUBSTANCE: method of determining the coordinates of an aircraft (AC) relative to the flight strip (FS) includes the radiation from the ground station of high-frequency signals, the measurement of heading angles of radio emission terrestrial source. During the landing approach of AC, direction finding of radiation source (measuring relative bearing and elevation angle, μm) of radar landing system (RLS) or AR of another AC, standing on the ground, is produced via the airborne radar (AR), in the direction, obtained by this method, range is measured by radiation from board of AC of interrogation signal different from interrogation signal of terrestrial radiation source by carrier frequency (and/or polarization), thus, obtaining place of AC relative to RLS or AR of AC standing on the ground in the form of heading angle, elevation and range angle from the known flight path, landing track, and the known location of terrestrial radiation source with respect to FS, the position of the AC relative to FS is determined, that is, the relative altitude of flight H, cross track angle Z, ground distance to FS X. The signal of beared radiation source (RLS or AR of LA standing on the ground) contains information about the direction of radiation and the time of signal radiation. Range measurements are performed by the active radar method, in which the signal of the AR of the approached AC is requested, and the RLS or AR of another AC standing on the ground radiates a response signal.

EFFECT: ensuring the possibility of high-precision positioning of the aircraft relative to the flight strip, improving flight safety and landing of aircrafts.

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Description

Technical field

The invention relates to the field of aviation, and more specifically to a method for determining the coordinates of an aircraft relative to the runway by a radio engineering landing system of an aircraft (LA), and can be used to provide landing on unequipped airfields and helipads, in combination with other landing systems, in as a backup landing system.

State of the art

Known for "Precise landing system", which includes at least four receivers, which are located in different, predetermined places. Each receiver has an accurate timer for measuring the time interval between the request signal detected by the receiver and the response signal from the aircraft transponder. The system also includes a processing device (computer) at the base station, which receives the measured time intervals from the receivers and calculates the position of the aircraft. The position of the aircraft is compared with the mathematical description of the desired approach path, and the positional error is then transmitted to the aircraft. Any desired approach path can be mathematically represented and can be used in the system, including paths having arcs, steps and segments [STOLTZ JOHN RYAN; CLAWSON CARL WILLIAM. Pat. KR171428B].

The disadvantages of this system include the need to place additional equipment at the aerodrome and aircraft, the need to transmit control commands to each specific aircraft via a data line.

Known USSR patent No. 1836642 dated 04/08/91, RF patent No. 2303796 dated January 26, 2006, RF patent No. 2348944 dated May 08, 2007, RF patent No. 2348981 dated July 3, 2007 by V.T. Artemov, describing methods for autonomously generating landing information for Aircraft and devices (system) for implementing these methods.

The main disadvantage of these inventions is the need to install on the ground a large number (several tens) of "radar point reflectors".

The known OSB system (Equipment landing system). The OSB includes a near driving radio marker station (BPRM) and a distant driving radio marker station (DPRM), including a driving radio station (ORS) and a marker radio beacon (MRM). The MRM emits an amplitude modulated signal at a carrier frequency of 75 MHz. Operating frequency range of ORS 150 ÷ 1300 kHz (λ≈2000 ÷ 230 m). The error in heading angles obtained on board an aircraft should not exceed ± 5 ° with a probability of 95% [“Aviation Rules. Part 139. Certification of aerodromes. Volume II Certification Requirements for Aerodromes. ” Interstate Aviation Committee. 1996. 84 p.].

The disadvantages of the OSP include the lack of navigational guidance along the glide path formed by electronic means, as a result of which such a system approach refers to an “inaccurate landing approach” [“FEDERAL AIRCRAFT FLIGHT REGULATIONS OF THE RUSSIAN FEDERATION” of 2002 No. 136/42 / 51. http://www.radioscanner.ru/avia/file/norm01.html, - www.radioscanner.ru (2 total), www.radioscanner.ru/avia/file/norm01.html ⋅ 152 KB].

Known radar landing system (RSP). In radar landing systems (RPS), the position of an aircraft in space is determined using a ground-based radar station (radar), information about the deviations of the aircraft from a given trajectory is transmitted to its board by radio. This circumstance allows us to significantly simplify the on-board radio receivers. Radars were widely used in naval aviation for landing aircraft on aircraft carriers [Belogorodsky S.L. Automation of aircraft landing control. Moscow, "Transport", 1972. 352 p.].

RSP provides collision avoidance of aircraft in the air, does not require additional on-board equipment, it is used for all, military and civilian, aircraft.

The structure of the RSP, in addition to radio stations and other equipment, includes:

- Dispatch radar (DRL) of the L-band (1250-1350 MHz, λ≈23 cm, in the secondary radar mode: request - 1030 MHz, response - 1090 MHz and 740 MHz), intended for monitoring and control of air traffic with a circular overview in radius up to 150 km;

- landing radar (PRL) of the X-band (9120, 9400 MHz, wavelength λ≈3.2 cm), designed to control the aircraft when it is reduced along the glide path [Vereshchaka AI, Olyanjuk P.V. "Aviation radio equipment." Moscow, "Transport", 1996. 343 p.].

The PRL of ground-based CPDs has two antennas scanning in the vertical and horizontal planes.

The main disadvantage of the CPD is the transmission of voice control commands by radio, as a result of which the aircraft is controlled with a delay, consisting of the delay of determining the deviation and transmission of the message by the dispatcher, the pilot's awareness and execution of the command, and the aircraft’s reaction to steering deviation. The absence on board the aircraft of instrumental information on the position of the aircraft relative to the runway (Runway) does not allow to realize the existing high accuracy of the CIR and, thereby, reduce the meteorological minimum landing.

Known system "Pennant", which was developed and used to land the Orbiter Ship "Buran" (OK).

The radio engineering system of automatic landing is designed to provide information for the automatic withdrawal of OK on the axis of the landing strip from a height of 7000 m, reducing along the optimal path, landing and run to a complete stop.

The operation of the azimuthal and elevation beacons is based on the principle of emitting high-frequency signals using narrowly directed scanning antennas. When scanning antennas in the emitted signals, information is transmitted on the angular position of the radiation pattern of the beacon by changing the time interval between the encoded pulse packets. On-board equipment measures the period corresponding to the middle of the received envelope and determines the angular position of the OK. The measurement of azimuth and elevation occurs sequentially in time. Goniometer equipment operates in the 2 cm wavelength range. The error in measuring the angular coordinates (3 sigma) 0.21 °. The scanning sector of the azimuthal beacon and the sector of the rangefinder repeater in the horizontal plane ± 30 °. The scanning sector of the elevated beacon in the vertical plane is 0.5 ÷ 30 °. Range 25 km ["EXPRESS REPORT" www.buran.ru/htm/pk.htm].

The disadvantages of this promising system include the need to install additional equipment and a rangefinder repeater on the runway on board the aircraft.

Known radar navigation systems with an active response, in which the signal is re-emitted by a relay device (transponder, transponder) located at the object whose location is determined. [Davydov P.S. (Ed.) et al. “Radio Navigation Systems of Aircraft”. Moscow, Transport. 1980, 448 pp.].

The disadvantage of systems with an active response, intended for use during approach, is the need to install at the airport, near the runway, additional equipment - radar transponders.

Closest to the claimed invention is the "Method of approach to the landing of the aircraft and the system for its implementation" author Alexandrova V.K. [patent RU 2559196 C1, 05.21.2014]. In this method, the distance to the runway on board the aircraft is determined by the interaction of the onboard and ground, installed at the end of the runway, sets of collision avoidance systems (ATP). Based on the obtained range and altitude obtained from the onboard altimeters, taking into account the temperature methodological correction, a glide path is formed and indicated.

The disadvantage of this invention is the need to install additional equipment, especially a set of ATP at the aerodrome (near the end of the runway), and it also provides, due to low accuracy, the use of an on-board ATP kit for direction finding of a radiation source - a ground-based ATP kit.

SUMMARY OF THE INVENTION

The objective of the invention is to develop a method of using existing ground and modernized, in accordance with the invention, aircraft equipment, providing the formation on board the aircraft instrument information about the position of the aircraft relative to the runway during approach.

The technical result, to which the claimed invention is directed, consists in providing the possibility of highly accurate determination of the position of the aircraft relative to the runway, in lowering the meteorological minimum during approach at low-equipped aerodromes, in the integrated use and reservation of other landing means, in increasing the safety of flight and landing of aircraft, especially in flight instrumentation.

To achieve the technical result in the proposed method for determining the coordinates of the aircraft relative to the runway, including radio emission from a ground station, measuring the course angles of a ground source of radio emission, during approach to the aircraft, using the airborne radar station, radar direction finding is performed (measuring heading angle and elevation angle) - a ground-based radar landing system (RPS) or radar of another aircraft with known coordinates, standing at quieter. In the direction thus obtained, a range is measured by emitting a request signal from the aircraft LA and receiving a response signal from the RCA antenna or the radar antenna of the aircraft on the ground, which differs from the request signal from a ground-based radio source with a carrier frequency (and / or polarization). From the two angles and ranges measured in this way, the known flight path, landing course, and the known location of the ground source of radiation relative to the runway, the position of the aircraft relative to the runway is determined, i.e. relative flight altitude N, lateral deviation Z, horizontal distance to runway X.

In this case, the signal of the direction-finding RSP or radar station of the aircraft on the ground contains information about the direction of radiation and the time of radiation of the signal.

In addition, range measurements are performed using the active radar method, in which the radar signal of the approaching aircraft is interrogated, and the radar or radar of another aircraft standing on the ground emits a response signal.

The proposed landing system is illustrated by the drawings shown in FIG. 1 is a plan view of FIG. 2 is a side view.

In FIG. 1 shows a diagram of determining the location of the aircraft relative to the runway (top view), where:

C - direction to the north (true or magnetic);

Kk - flight course;

KUR - heading angle of the radio station (target);

ПЦ - bearing of the target;

Δψ is the angle between the landing course and the bearing of the target;

D _mountains - horizontal distance to the beacon;

Z - lateral deviation of the aircraft from the axis of the runway;

Z ₀ - lateral deviation of the beacon from the axis of the runway;

PC - landing course.

In FIG. 2 shows a diagram for determining the relative flight altitude, where:

α _vis - the angle of sight of the beacon;

θ is the pitch angle;

μ _m - elevation angle of the beacon;

μ _la - elevation angle of the aircraft;

D _tilt - slant range (measures radar);

H ₀ - the height of the beacon relative to the runway;

H is the relative flight altitude.

The proposed method is carried out in the following sequence.

High-frequency signals are emitted from a ground station (vertical and horizontal scanning antennas of a radar landing system — a radar system or a radar antenna of another aircraft standing on the ground with known coordinates relative to the runway). During an approach to an aircraft using an airborne radar station (DRL), the direction of the radio emission source (measurement of the heading angle KUR and elevation angle, μm) of the radar landing system (RPS) or the radar of another aircraft on the ground is measured.

Direction finding signals of these antennas, as a result of which onboard the aircraft receive heading angle and elevation angle of the target (ground antenna). Direction finding of a radiation source is possible both along the main beam and along the side lobes.

To measure the range of the radar, it periodically emits a request signal in a certain direction, as indicated above, in the direction of the ground antenna (antennas, radar and other radar, standing on the ground) at a frequency different from the frequency of the ground station. The interrogation signal may also differ from the signal of the terrestrial radio emission source by polarization. To eliminate the influence of reflections from the earth, monopulse radar methods are used, i.e. the measurements are made in the direction of the minimum of the received signal of the differential radiation pattern.

If necessary, in order to obtain the maximum amplitude of the signal reflected from the target (ground-based radar antenna or radar), the distance to the radiation source is measured at the moment when the antenna is aimed at the aircraft. For this purpose, the maximum amplitude of the interrogation signal is determined on board the aircraft, and the direction measured at this moment to the ground emitter is considered the direction of the ground antenna to the aircraft. At this moment (for a short time) and make a range measurement method "request - response".

Range measurements are also carried out by the active radar method, in which the radar signal is interrogated, and the ground (radar of another aircraft standing on the ground, or radar) emits a response signal.

Having received the position of the aircraft relative to the RSP or radar in the form of 2 angles and range, knowing the flight path, landing course (PC) and the location of the RSP or ground radar relative to the runway, using the diagrams shown in FIG. 1 and 2, the relative flight altitude H, lateral deviation Z, and horizontal distance to runway X are obtained as follows.

From FIG. one:

Here

From FIG. 2:

Substituting (3 and 4) in (1 and 2), we finally get:

From FIG. 2:

Here

Substituting (8) in (7), we finally obtain:

The obtained value of the relative height is used for comparison with the readings of the airborne altimeter in order to avoid gross errors in the airdrome pressure display in the Colesman window. This value can also be used in case of a failure of the air signal system, instead of (or for duplication and joint processing) of the radio altimeter signal.

The obtained value of lateral deviation Z is used for indication in both automatic and director control systems. The value of the relative height H obtained by formula (9) is compared with a given height (by subtracting a given height from the current height determined by formula (9), and the obtained difference ΔН is used for indication in both automatic and director control systems.

The specified height is determined by the formula:

where ΔХ is the distance from the end of the runway to the line of intersection of the glide path plane with the earth's surface;

CNT - the angle of inclination of the glide path;

X is the distance to the end of the runway, determined by the formula (2).

The obtained value Nzad give the crew an indication.

The glide path of the reduction can also be built on the basis of the information obtained on the range to the runway and flight altitude according to the method described in patent RU 2559196 C1, 05.21.2014.

If the signal of the direction-finding ground emitter contains information about the direction of radiation, then this information is used for comparison and joint processing with the data obtained by the radar of the approaching aircraft to increase the accuracy and increase the reliability of the received coordinates.

Information about the time the signal was emitted by the ground emitter is used on board the aircraft to determine the range using a technique similar to that used in satellite navigation systems. The range obtained in this way is used for comparison and joint processing with the range obtained by radar.

If the signals of the ground-based radar of another aircraft standing on the ground, the directional and glide path antennas of the RSP contain information about the direction of radiation, then it is used for joint processing on board the aircraft.

Range measurements are also performed by the active radar method, in which the radar signal is interrogated, and the ground (radar of another aircraft or radar) emits a response signal.

Claims (3)

1. The method of determining the coordinates of the aircraft (LA) relative to the runway (runway), including radiation from a ground station of high-frequency signals, measuring the course angles of a ground source of radio emission, characterized in that during the approach to the aircraft using the on-board radar station ( Radar) determine the direction of the radiation source (measuring the heading angle KUR and elevation, μm) of the radar landing system (radar) or radar of another aircraft standing on the ground in the direction thus obtained and they make a range measurement by emitting from the aircraft an interrogation signal different from the interrogation signal of a ground-based source of radio emission with a carrier frequency (and / or polarization), having received an aerospace position relative to a radar or radar station of another aircraft on the ground in the form of two angles (KUR, μm) and range, according to the known flight rate, landing rate and the known location of the ground source of radio emission relative to the runway determine the position of the aircraft relative to the runway, i.e. relative flight altitude N, lateral deviation Z, horizontal distance to runway X. 2. The method of determining the coordinates of the aircraft relative to the runway according to claim 1, characterized in that the signal of the direction-finding source of the radio emission (RSP or radar station of the aircraft on the ground) contains information about the direction of radiation and the time of radiation of the signal. 3. The method of determining the coordinates of the aircraft relative to the runway according to paragraphs. 1, 2, characterized in that the range measurements are made by active radar, in which the radar signal of the approaching aircraft is interrogated, and the radar or radar of another aircraft standing on the ground emits a response signal.

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