WO1989003050A1 - Systeme de transmission de donnees de position derivees de radars - Google Patents

Systeme de transmission de donnees de position derivees de radars Download PDF

Info

Publication number
WO1989003050A1
WO1989003050A1 PCT/GB1988/000778 GB8800778W WO8903050A1 WO 1989003050 A1 WO1989003050 A1 WO 1989003050A1 GB 8800778 W GB8800778 W GB 8800778W WO 8903050 A1 WO8903050 A1 WO 8903050A1
Authority
WO
WIPO (PCT)
Prior art keywords
data
aircraft
display
radar
positional
Prior art date
Application number
PCT/GB1988/000778
Other languages
English (en)
Inventor
John Peter Millward
Original Assignee
John Peter Millward
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by John Peter Millward filed Critical John Peter Millward
Publication of WO1989003050A1 publication Critical patent/WO1989003050A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/003—Transmission of data between radar, sonar or lidar systems and remote stations
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/93—Radar or analogous systems specially adapted for specific applications for anti-collision purposes
    • G01S13/933—Radar or analogous systems specially adapted for specific applications for anti-collision purposes of aircraft or spacecraft

Definitions

  • TRANSMISSION SYSTEM FOR RADAR DERIVED POSITIONAL DATA This invention relates to extended uses of radar.
  • FIGS 1A and IB of the drawings show schematically two slightly different displays on a ground radar screen.
  • the centre of each screen C corresponds to the position of the ground radar transceiver.
  • the positions of two aircraft A, B are shown over five scans of the radar, for example A1A to A5A for aircraft A in Figure 1A.
  • the paths AA, BA, AB and BB of the aircraft have been marked on the drawing, but this information would not be available to the .air traffic controller.
  • Radar is not fitted to the majority of aircraft because it is expensive, bulky and heavy. Indeed, it is believed that only a very few military aircraft are fitted with radar, and in those cases the radar has a limited scan.
  • a radar system comprising: a ground radar station for detecting the positions of objects relative thereto; a transmitter for transmitting data derived from the detected positions; and a mobile station operable to receive the transmitted data and to provide a signal dependent upon the path relative to the mobile station of an object detected by the ground station.
  • the signal may be a visual display of the path of the detected object or objects and/or an indication as to whether or not the path of any detected object appears to be on a collision or near-collision course with the mobile station.
  • Figures IC and ID show examples of displays which could be provided for the pilot or navigator corresponding to Figures 1A and " IB, respectively, (but at half the scale) when the display is centred on the current position of aircraft A, that is position AC in Figure IC and position AD in Figure 5D.
  • the successive positions B1C to B5C of aircraft B in Figure IC can easily be extrapolated to determine that aircraft B will pass behind aircraft A.
  • the extrapolation performed in the case of Figure ID upon the points BID to B5D immediately shows that aircraft B is on a collision course with aircraft A, and therefore the pilot or navigator of aircraft A can simply see that evasive action needs to be considered.
  • a ground radar station for detecting the positions of objects relative thereto, in combination with a transmitter for transmitting data derived from the detected positions.
  • a positional display apparatus comprising: means to receive positional data of an object in terms of one co-ordinate system; means to convert the positional data to being in terms of a further co-ordinate system relative to the position of the apparatus; and means to display the converted positional data.
  • a radar system in which data from which a radar screen image could be constructed is transmitted, and in which an aircraft receives the data and constructs a radar screen image in which the image of the aircraft in the display remains stationary despite movement of the aircraft.
  • Figures 1A and IB illustrate a conventional ground radar display
  • FIGS IC and ID illustrate a display which may be provided in an aircraft in accordance with the invention
  • Figure 2 is a block diagram schematically illustrating radar station equipment
  • Figure 3 is a geometrical diagram used to explain the operation of an encoder in the radar station
  • Figure 4 shows a transmitted data format
  • Figure 5 is a block diagram schematically illustrating an apparatus for fitting to an aircraft
  • Figure 6 is an example of a display of the apparatus of Figure 5.
  • a ground radar transceiver 10 has an output serially supplying signals corresponding to the range R. and bearing
  • An encoder 12 receives the signals R.
  • transceiver calculates the latitude X. and longitude Y. of each of the N points and serially
  • a controller 16 causes a VHF radio transmitter 18 to package and transmit the data in the format shown in Figure 4.
  • Each transmission begins with a predetermined start code, then the latitude and longitude of the radar transceiver and a predetermined separation code, then the latitude and longitude and a separation code for each point 1 to N, and then a predetermined end code. Transmissions are repeated at a predetermined rate of, for example, _L0 transmissions per minute, which conveniently corresponds to the usual scan rate of 10 scans per minute for most UK ground radar.
  • the apparatus mounted in ' the aircraft comprises a computer 20 which receives signals from a VHF radio receiver 22 and drives a liquid crystal panel display 24.
  • the computer can also address and read a position data memory 26 and is associated with a keyboard 28 for manual data entry and control of the system.
  • the data transmitted by the ground transmitter for one scan is received by the receiver 22 and unpackaged, and the batch of data
  • the position memory 26 The batch of data for the next scan is stored in another one of the five sections of the memory 26, and so on.
  • the memory 26 is cyclically refreshed so that it holds five batches of position data for the last five scans of the radar, and the computer memorises in which portion of the memory the most recent batch of data is held.
  • the aircraft pilot or navigator In order to initiate the system, the aircraft pilot or navigator enters via the keyboard 28 his estimated latitude X and longitude Y .
  • the keyboard 28 his estimated latitude X and longitude Y .
  • the position of the aircraft will correspond to one of the positions received from the ground radar.
  • the position X , Y is stored. This process is
  • a) has stored five batches of positional data; b) knows the order in which the batches have been stored; and c) knows which data pair in each batch corresponds its own position.
  • the computer determines the average bearing of the host aircraft during the 5-scan period.
  • the computer then performs a co-ordinate conversion process an each set of data.
  • the conversion process has the following effects:
  • the co-ordinate system is expanded or contracted so that the scale of the image represented by the data is enlarged or made smaller in accordance with a factor which may be entered via the keyboard.
  • the data as it is transformed is supplied to the display 24, where, for each data pair a point is displayed at co-ordinates on the display panel corresponding to the converted co-ordinates, the y-axis of the converted co-ordinate system (ie the aircraft bearing) corresponding to the vertical direction of the display panel and the origin ⁇ f the converted co-ordinate system corresponding to the centre of the display panel.
  • each displayed point is made to be dependent on the particular batch of data from which the point is derived, so that data from the most recent radar scan is brightest and/or largest and that from the earliest radar scan is dimmest and/or smallest.
  • another aircraft moving relative to the host aircraft will be displayed as a row of five points having brightness and/or size increasing in the direction of travel of the other aircraft.
  • the host aircraft will be displayed as a single point on the display panel, because as a result of the conversion process the host aircraft's own position becomes the origin and centre of the screen for each batch of data.
  • the display panel is updated every time a further batch of data is received.
  • the average bearing of the host aircraft over the last five-scan period is determined and continually updated.
  • the speed and average bearing of the host aircraft may be calculated from the most recent two pairs of position co-ordinates, and an extrapolation process may be carried out using the speed and bearing in order to determine which data pair in the next batch of data is likely to represent the new position of the host aircraft.
  • the aircraft pilot or navigator may enter via the keyboard 28 his estimated bearing and speed, in addition to the estimated latitude and longitude.
  • the bearing of the host aircraft is determined from the own-position co-ordinate pairs in the five batches of data. Since these five positions are close together, errors may be introduced, and, whilst these errors will not substantially affect the display of relative positions of other aircraft with respect to the host aircraft, rotational variations may be introduced in the display as between adjacent displayed images.
  • the bearing may b.e entered by the pilot or navigator via the keyboard and may be updated each time a change of course is made.
  • the host aircraft is fitted with a compass having an electrical output indicating the current bearing, that electrical output may be used to supply bearing information to the display apparatus.
  • the computer may be programmed to compare the position data in the five batches of data and to determine which position co-ordinate pairs in the batches relate to the same aircraft. Having done this the courses of all of the other aircraft are extrapolated and the computer determines whether any other aircraft is expected to collide with or come within a predetermined distance of the host aircraft. If so, this is indicated to the pilot or navigator, for example, by flashing on the display the points representing the aircraft causing the danger, by flashing a line indicating the other aircraft's course, and/or by a visual or audible alarm. Furthermore, the computer may determine the expected time to collision and cause the display to display that time.
  • the altitude data and/or identity code data for the aircraft is included in the transmissions in the available space marked "blank" in Figure 4, and this additional data is stored in the memory 26 of the host aircraft.
  • the computer then causes the display panel 24 to indicate adjacent the most recent position point for each aircraft the most recently received altitude and/or the identity code for that aircraft.
  • the altitude of the host aircraft may be input to the computer, for example, manually via the keyboard, from an onboard altimeter, or from the received data from the ground radar, and the differences between the altitudes of the host aircraft and the other aircraft may be taken into account in assessing the risk of collision.
  • the computer may be programmed not to display the locations of aircraft having more than a predetermined difference in altitude from that of the host aircraft so that .a less cluttered display may be provided.
  • the altitude data or identity code of the host aircraft received from the ground radar may be compared with altitude data entered via the keyboard or from an onboard altimeter or with an identity code stored by the computer in checking that the computer has correctly identified from the received data that which relates to the host aircraft.
  • ground radar stations may transmit on different frequencies, and the pilot or navigator of the host aircraft may tune to the desired frequency.
  • the host aircraft may receive on two or more channels and the pilot or navigator may select whether to display the da£a from one ground radar station, the other, or both.
  • the ground radar stations may all transmit on the same frequency, but with time-sequenced transmissions of the batches of data, so that no two adjacent stations transmit at the same time, and again the host aircraft may select which data from the various received transmissions to display.
  • the apparatus fitted to the aircraft may also be provided with a PROM containing information about the height and locations of high ground and structures in the area likely to be covered by the host aircraft, and this information may be displayed on the display panel in the appropriate location and marked with the relevant height.
  • the apparatus fitted to the aircraft may be provided with a PROM containing map data, and thus a map may also be diplayed on the display and may move across the display as the position of the host aircraft moves.
  • the PROM may be arranged so that it is easily removable and can be replaced by a different PROM covering a different area.
  • the display may be provided with true north in the upward direction, and a bearing indicator may be provided to show the bearing of the host aircraft.
  • the apparatus fitted to the aircraft has two modes, namely a "map mode” and a "flight mode".
  • Map mode the display does not move so that it is centered on the position of the host aircraft, but instead it is movable under the direction of cursor keys of the keyboard 28, or alternatively an associated joystick control.
  • Map mode is particularly useful in initiating the system when provided with the following facilities. The pilot adjusts the portion of the map which is displayed until it covers the area in which the host aircraft is located. The display then, therefore, shows the positions of aircraft, as transmitted by the ground radar station, moving relative to the ground. The pilot then enters his estimated position, speed and bearing .
  • the estimated course of the host aircraft is then displayed on the screen, preferably in a different manner to the displayed courses determined from the data received from the ground radar, for example, as a series of five small circles rather than five dots.
  • the simulated course will lie adjacent to (or be superimposed on), and move with the course of, the host aircraft as determined from the data received from the ground radar station. It is therefore a simple matter for the pilot to determine which of the courses displayed on the screen, as received from the ground radar station, corresponds to the course of the host aircraft.
  • the pilot can then adjust his estimated position using the cursor controls or joystick control so that it generally coincides with the displayed course which he considers represents his own aircraft, and can then press a flight mode button on the keyboard.
  • the computer 20 determines that the course of the aircraft received from ground radar which lies most closely adjacent to the pilot's estimated course is the course of the host aircraft and continues by forming the display in the manner described above with the position of the host aircraft centered on the display.
  • the current latitude and longitude of the host aircraft is stored once the aircraft has landed and the apparatus has been switched off (apart from the memory continuing to be powered by a back-up battery), and this information is then available to the pilot when he next switches on the apparatus ready for a further flight.
  • ground radar stations in the United Kingdom have a scan period of six seconds, and therefore if one batch of data is transmitted for each scan, the displayed five batches of data will represent the course of each aircraft over 24 seconds, and the relative speeds of the aircraft -can be determined from the spacings of the dots in the display.
  • a few ground radar stations in the United Kingdom scan at a different rate, for example having a 10 second period.
  • some adjustment should be made so that, whichever type of station is transmitting, the display always displays the course of an aircraft over a predetermined period of time, and this is, of course, essential, if the display is displaying a mixture of data from two different ground radar stations operating at different rates.
  • Such adjustment may either be made at the ground radar station so that a station scanning with a ten second period transmits as if it were scanning with a six second period.
  • the adjustment may be made in the host aircraft.
  • Figure 6 illustrates a display incorporating some of the modifications or developments described above.
  • the display has N-S, E-W cross-hairs 30; marked range-circles 32; a marker 36 at the top of the display showing the host aircraft's heading; and digital latitude, longitude and bearing information 38 of the host aircraft at the top-right corner of the display.
  • An aircraft approaching from the East is on a collision course, and a warning line 40 indicating its course is flashing.
  • An aircraft to the West-South-West has an altitude indication 42.
  • a slower aircraft having closer spaced markings 44 to the South-South-East is turning to port.

Landscapes

  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Electromagnetism (AREA)
  • Traffic Control Systems (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

Système radar dans lequel une station radar terrestre transmet dees donnéees de position d'objets détectés, et un avion reçoit les données et les affiche sur un écran, après avoir premièrement transformé les données de sorte que l'avion hôte forme le centre de l'affichage. Le système agit par conséquent comme si l'avion hôte avait son propre appareil radar. Comme l'affichage se trouvant dans l'avion est centré sur l'avion hôte, le pilote peut beaucoup plus facilement détecter s'il suit une route de collision avec un autre avion, qu'un aiguilleur du ciel ne peut détecter si deux avions sur son écran sont sur une route de collision.
PCT/GB1988/000778 1987-09-28 1988-09-22 Systeme de transmission de donnees de position derivees de radars WO1989003050A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8722730A GB2210528A (en) 1987-09-28 1987-09-28 Radar
GB8722730 1987-09-28

Publications (1)

Publication Number Publication Date
WO1989003050A1 true WO1989003050A1 (fr) 1989-04-06

Family

ID=10624471

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1988/000778 WO1989003050A1 (fr) 1987-09-28 1988-09-22 Systeme de transmission de donnees de position derivees de radars

Country Status (3)

Country Link
AU (1) AU2487388A (fr)
GB (1) GB2210528A (fr)
WO (1) WO1989003050A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1136839A1 (fr) * 2000-03-24 2001-09-26 Terma Elektronik A/S Dispositif et procédé de tranfert d'informations radar

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103914888B (zh) * 2014-03-31 2016-05-11 四川九洲空管科技有限责任公司 一种机载防撞系统数据记录分析方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3750166A (en) * 1971-06-11 1973-07-31 J Dearth Pilot data system
US3821735A (en) * 1973-01-29 1974-06-28 Burroughs Corp Digital data refreshing apparatus for radar display system
FR2356153A1 (fr) * 1976-04-27 1978-01-20 Cabrol Michel Visualiseur de route aerospatiale et maritime
US4197538A (en) * 1976-08-02 1980-04-08 Stocker Godfrey H Pilot's traffic monitoring system
US4274096A (en) * 1979-07-09 1981-06-16 Dennison Terry A Aircraft proximity monitoring system

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE467009A (fr) * 1945-07-31
GB1024982A (en) * 1963-02-21 1966-04-06 Marconi Co Ltd Improvements in or relating to radio navigation aids
GB1011957A (en) * 1963-05-29 1965-12-01 Smith & Sons Ltd S Improvements in or relating to apparatus for the display of information as to the positions of moving and stationary objects
GB1063214A (en) * 1965-04-12 1967-03-30 Marconi Co Ltd Improvements in or relating to radio navigation aids

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3750166A (en) * 1971-06-11 1973-07-31 J Dearth Pilot data system
US3821735A (en) * 1973-01-29 1974-06-28 Burroughs Corp Digital data refreshing apparatus for radar display system
FR2356153A1 (fr) * 1976-04-27 1978-01-20 Cabrol Michel Visualiseur de route aerospatiale et maritime
US4197538A (en) * 1976-08-02 1980-04-08 Stocker Godfrey H Pilot's traffic monitoring system
US4274096A (en) * 1979-07-09 1981-06-16 Dennison Terry A Aircraft proximity monitoring system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1136839A1 (fr) * 2000-03-24 2001-09-26 Terma Elektronik A/S Dispositif et procédé de tranfert d'informations radar

Also Published As

Publication number Publication date
AU2487388A (en) 1989-04-18
GB8722730D0 (en) 1987-11-04
GB2210528A (en) 1989-06-07

Similar Documents

Publication Publication Date Title
EP0324195B1 (fr) Instrument indicateur de conditions de vol intégré et primaire
EP1658473B1 (fr) Systeme d'affichage de gestion de vol integre et de commande de trafic aerien textuel ainsi que procede associe
EP0200787B1 (fr) Systeme de visualisation d'une zone d'alarme ou d'avions dangereux dans un dispositif de prevention anticollision d'un avion
US5343395A (en) Aircraft landing guidance system and method
US6708090B2 (en) Method, apparatus and computer program product for managing line-of-sight communications
US3925750A (en) Air traffic control system
US5978715A (en) Apparatus and method for aircraft display and control
US4197538A (en) Pilot's traffic monitoring system
US5820080A (en) Precision equivalent landing system using gps and an altimeter
US4490117A (en) Inflight IFR procedures simulator
US6112141A (en) Apparatus and method for graphically oriented aircraft display and control
US6006158A (en) Airport guidance and safety system incorporating lighting control using GNSS compatible methods
US3521227A (en) Display system for providing integrated display of aircraft information
US5329277A (en) Displays and display systems
US20030083804A1 (en) Computer human methods for the control and management of an airport
WO1993024846A1 (fr) Radar a balayage horizontal et vertical automatique
EP0774148A1 (fr) Systeme de controle du trafic aerien par satellite
EP0175967B1 (fr) Système de navigation, communication et surveillance basé sur le DME
WO1989003050A1 (fr) Systeme de transmission de donnees de position derivees de radars
US5936574A (en) Device for monitoring the distance between two objects
JP3526402B2 (ja) 着陸誘導システム
US6275771B1 (en) Time multiplexed global positioning system cell location beacon system
US2520600A (en) Air traffic control
EP1258851A2 (fr) Dispositif de navigation
US2513490A (en) Selective communication system between ground station and a plurality of mobile stations

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AT AU BB BG BR CH DE DK FI GB HU JP KP KR LK LU MC MG MW NL NO RO SD SE SU US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE BJ CF CG CH CM DE FR GA GB IT LU ML MR NL SE SN TD TG

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642