IPC 7 English version G01S !A-G01S 3/86

IPC ⁷ English version

G01S-G01S00386

G01S 5/00 - G01S 7/64

SECTION G – PHYSICS

G 01

MEASURING (counting G06M); TESTING

G 01 S

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 (detecting masses or objects by methods not involving reflection or reradiation of radio, acoustic or other waves G01V)

Notes

(1)

In this subclass, the following term is used with the meaning indicated: [6]

–

"transponder" means an arrangement which reacts to an incoming interrogating or detecting wave by emitting a specific answering or identifying wave. [6]

(2)

Attention is drawn to the Notes following the title of class G01 and to Note (1) following the title of subclass G09B.

Subclass Index

BEACON SYSTEMS; DIRECTION-FINDERS; POSITION FIXING

G01S 1/00; G01S 3/00; G01S 5/00

RADAR OR ANALOGOUS SYSTEMS

Details

G01S 7/00

Using radio waves, using other waves where the wavelength or the kind of wave is irrelevant or unspecified

G01S 13/00

Using acoustic waves

G01S 15/00

Using electromagnetic waves other than radio waves

G01S 17/00

SYSTEMS FOR DETERMINING DISTANCE OR VELOCITY NOT USING REFLECTION OR RERADIATION

G01S 11/00

Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith (position-fixing by co-ordinating a plurality of determinations of direction or position lines G01S 5/00) [2]

using radio waves

Details

Means for providing multiple indication, e.g. coarse and fine indications

Systems for determining direction or position line

using amplitude comparison of signals transmitted sequentially from aerials or aerial systems having differently-oriented overlapping directivity-characteristics, e.g. equi-signal A-N type

the signals being transmitted sequentially from an aerial or aerial system having the orientation of its directivity characteristic periodically varied, e.g. by means of sequentially effective reflectors

using amplitude comparison of signals transmitted simultaneously from aerials or aerial systems having differently-oriented overlapping directivity-characteristics

Azimuthal guidance systems, e.g. system for defining aircraft approach path, localiser system

Elevational guidance systems, e.g. system for defining aircraft glide path

using a comparison of transit time of synchronised signals transmitted from non-directional aerials or aerial systems spaced apart, i.e. path-difference systems

the synchronised signals being frequency modulations on carrier waves and the transit times being compared by measuring difference of instantaneous frequencies of received carrier waves

the synchronised signals being pulses or equivalent modulations on carrier waves and the transit times being compared by measuring the difference in arrival time of a significant part of the modulations

Systems in which pulses or time-base signals are generated locally at the receiver and brought into predetermined time-relationship with received signals, e.g. pulse duration coincides with time interval between arrival of significant part of modulation of signals received from first and second aerials or aerial systems

wherein the predetermined time-relationship is maintained automatically

the synchronised signals being continuous waves or intermittent trains of continuous waves, the intermittency not being for the purpose of determining direction or position line and the transit times being compared by measuring the phase difference

Systems in which the signals received, with or without amplification, or signals derived therefrom, are compared in phase directly

Systems in which first and second synchronised signals are transmitted from both aerials or aerial systems and a beat frequency, obtained by heterodyning the first signals with each other is compared in phase with a beat frequency obtained by heterodyning the second signals with each other

Systems in which a beat frequency, obtained by heterodyning the synchronised signals, is compared in phase with a reference signal having a phase substantially independent of direction

using comparison of (1) the phase of the envelope of the change of frequency, due to Doppler effect, of the signal transmitted by an aerial moving, or appearing to move, in a cyclic path with (2) the phase of a reference signal, the frequency of this reference signal being synchronised with that of the cyclic movement, or apparent cyclic movement, of the aerial

the apparent movement of the aerial being produced by cyclic sequential energisation of fixed aerials

Conical-scan beam beacons transmitting signals which indicate at a mobile receiver any displacement of the receiver from the conical-scan axis, e.g. for "beam-riding" missile control [5]

Rotating or oscillating beam beacons defining directions in the plane of rotation or oscillation [5]

Broad-beam systems producing at a receiver a substantially continuous sinusoidal envelope signal of the carrier wave of the beam, the phase angle of which is dependent upon the angle between the direction of the receiver from the beacon and a reference direction from the beacon, e.g. cardioid system [5]

wherein the phase angle of the direction-dependent envelope signal is a multiple of the direction angle, e.g. for "fine" bearing indication [5]

wherein the phase angle of the direction-dependent envelope signal is compared with a non-direction- dependent reference signal [5]

wherein the phase angles of a plurality of direction-dependent envelope signals produced by a plurality of beams rotating at different speeds or in different directions are compared [5]

Narrow-beam systems producing at a receiver a pulse-type envelope signal of the carrier wave of the beam, the timing of which is dependent upon the angle between the direction of the receiver from the beacon and a reference direction from the beacon; Overlapping broad beam systems defining a narrow zone and producing at a receiver a pulse-type envelope signal of the carrier wave of the beam, the timing of which is dependent upon the angle between the direction of the receiver from the beacon and a reference direction from the beacon [5]

Timing the pulse-type envelope signals derived by reception of beam [5]

wherein a characteristic of the beam transmitted or of an auxiliary signal is varied in time synchronously with rotation or oscillation of the beam [5]

Varying frequency of beam signal or of auxiliary signal [5]

Varying phase-relationship between beam and auxiliary signal [5]

Varying pulse timing, e.g. varying interval between pulses radiated in pairs [5]

Superimposing direction-indicating intelligence signals, e.g. speech, Morse [5]

Marker, boundary, call-sign, or like beacons transmitting signals not carrying directional information

using electromagnetic waves other than radio waves

using ultrasonic, sonic, or infrasonic waves (signalling devices G08B)

Details [5]

Systems for determining direction or position line (sound focusing or directing using electrical steering of transducer arrays, e.g. beam steering, in general, G10K 11/34) [5]

using amplitude comparison of signals transmitted from transducers or transducer systems having differently-oriented characteristics [5]

using a comparison of transit time of synchronised signals transmitted from non-directional transducers or transducer systems spaced apart, i.e. path-difference systems [5]

Rotating or oscillating beam beacons defining directions in the plane of rotation or oscillation [5]

Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received (position-fixing by co-ordinating a plurality of determinations of direction or position lines G01S 5/00; for geophysical measurement G01C; telescope mountings G02B)

using radio waves

Details

Means for increasing effective directivity, e.g. by combining signals having differently- oriented directivity characteristics, by sharpening the envelope waveform of the signal derived from a rotating or oscillating beam aerial (comparing amplitude of signals having differently-oriented directivity characteristics to determine direction G01S 3/16, G01S 3/28; modifications of aerials or aerial systems H01Q)

Means for reducing polarisation errors, e.g. by use of Adcock or spaced loop aerial systems

Means for reducing or compensating for quadrantal, site, or like errors

Means for determining sense of direction, e.g. by combining signals from directional aerial or goniometer search coil with those from non-directional aerial (determining direction by amplitude comparison of signals derived by combining directional and non-directional signals G01S 3/24, G01S 3/34)

Systems for determining direction or deviation from predetermined direction

using amplitude comparison of signals derived sequentially from receiving aerials or aerial systems having differently-oriented directivity characteristics or from an aerial system having periodically-varied orientation of directivity characteristic

derived directly from separate directional aerials

derived by sampling signal received by an aerial system having periodically-varied orientation of directivity characteristic

derived from different combinations of signals from separate aerials, e.g. comparing sum with difference

the separate aerials comprising one directional aerial and one non-directional aerial, e.g. combination of loop and open aerials producing a reversed cardioid directivity characteristic

the separate aerials having differently- oriented directivity characteristics

using amplitude comparison of signals derived simultaneously from receiving aerials or aerial systems having differently-oriented directivity characteristics

derived directly from separate directional systems

derived from different combinations of signals from separate aerials, e.g. comparing sum with difference

the separate aerials comprising one directional aerial and one non-directional aerial, e.g. combination of loop and open aerials producing a reversed cardioid directivity characteristic

the separate aerials having differently- oriented directivity characteristics

using adjustment of real or effective orientation of directivity characteristic of an aerial or an aerial system to give a desired condition of signal derived from that aerial or aerial system, e.g. to give a maximum or minimum signal (G01S 3/16, G01S 3/28 take precedence)

adjusting orientation of a single directivity characteristic to produce maximum or minimum signal, e.g. rotatable loop aerial, equivalent goniometer system

the desired condition being maintained automatically

the adjustment being varied periodically or continuously until it is halted automatically when the desired condition is attained

using aerials spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems

the waves arriving at the aerials being continuous or intermittent and the phase difference of signals derived therefrom being measured

the waves arriving at the aerials being pulse modulated and the time difference of their arrival being measured

using a receiving aerial moving, or appearing to move, in a cyclic path to produce a Doppler variation of frequency of the received signal

the apparent movement of the aerial being produced by coupling the receiver cyclically and sequentially to each of several fixed spaced aerials

Conical-scan beam systems using signals indicative of the deviation of the direction of reception from the scan axis

Rotating or oscillating beam systems using continuous analysis of received signal for determining direction in the plane of rotation or oscillation or for determining deviation from a predetermined direction in such a plane (G01S 3/14 takes precedence)

Broad-beam systems producing in the receiver a substantially-sinusoidal envelope signal of the carrier wave of the beam, the phase angle of which is dependent upon the angle between the direction of the transmitter from the receiver and a reference direction from the receiver, e.g. cardioid system

wherein the phase angle of the signal is indicated by a cathode-ray tube

wherein the phase angle of the signal is determined by phase comparison with a reference alternating signal varying in synchronism with the directivity variation

Narrow-beam systems producing in the receiver a pulse-type envelope signal of the carrier wave of the beam, the timing of which is dependent upon the angle between the direction of the transmitter from the receiver and a reference direction from the receiver; Overlapping broad-beam systems defining in the receiver a narrow zone and producing a pulse-type envelope signal of the carrier wave of the beam, the timing of which is dependent upon the angle between the direction of the transmitter from the receiver and a reference direction from the receiver

wherein the timing of the pulse-type envelope signal is indicated by cathode-ray tube (radar cathode-ray tube indicators providing co-ordinated display of distance and direction G01S 7/10)

wherein the timing of the pulse-type envelope signal is determined by bringing a locally-generated pulse-type signal into coincidence or other predetermined time-relationship with the envelope signal

Diversity systems specially adapted for direction-finding

Multi-channel systems specially adapted for direction-finding, i.e. having a single aerial system capable of giving simultaneous indications of the directions of different signals (systems in which the directions of different signals are determined sequentially and displayed simultaneously G01S 3/04, G01S 3/14)

using electromagnetic waves other than radio waves

781

Details [5]

782

Systems for determining direction or deviation from predetermined direction [5]

783

using amplitude comparison of signals derived from static detectors or detector systems [5]

784

using a mosaic of detectors [5]

785

using adjustment of orientation of directivity characteristics of a detector or detector system to give a desired condition of signal derived from that detector or detector system [5]

786

the desired condition being maintained automatically [5]

787

using rotating reticles producing a direction-dependent modulation characteristic [5]

788

producing a frequency modulation characteristic [5]

789

using rotating or oscillating beam systems, e.g. using mirrors, prisms [5]

using ultrasonic, sonic, or infrasonic waves

801

Details [5]

802

Systems for determining direction or deviation from predetermined direction (sound-focusing or directing using electrical steering of transducer arrays, e.g. beam steering, in general, G10K 11/34) [5]

803

using amplitude comparison of signals derived from receiving transducers or transducer systems having differently-oriented directivity characteristics [5]

805

using adjustment of real or effective orientation of directivity characteristics of a transducer or transducer system to give a desired condition of signal derived from that transducer or transducer system, e.g. to give a maximum or minimum signal [5]

807

the desired condition being maintained automatically [5]

808

using transducers spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems [5]

809

with means for adjusting phase or compensating for time-lag errors

with indication presented on cathode-ray tubes

with means for eliminating undesired waves, e.g. disturbing noises

G01S 5/00 - G01S 7/64