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

GPHYSICS G01Measuring instruments G01SRADIO 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

G01S3/00Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received

G01S3/02using radio waves G01S3/023Monitoring or calibrating G01S3/026Simulating means therefor G01S3/04Details G01S3/043Receivers G01S3/046Displays or indicators G01S3/06Means for increasing effective directivity G01S3/065by using non-directional aerial G01S3/08Means for reducing polarisation errors G01S3/085by using spaced loop aerial systems G01S3/10Means for reducing or compensating for quadrantal, site, or like errors G01S3/12Means for determining sense of direction G01S3/14Systems for determining direction or deviation from predetermined direction G01S3/143by vectorial combination of signals derived from differently oriented antennae G01S3/146by comparing linear polarisation components G01S3/16using 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 G01S3/18derived directly from separate directional aerials G01S3/20derived by sampling signal received by an aerial system having periodically-varied orientation of directivity characteristic G01S3/22derived from different combinations of signals from separate aerials G01S3/24the separate aerials comprising one directional aerial and one non-directional aerial G01S3/26the separate aerials having differently-oriented directivity characteristics G01S3/28using amplitude comparison of signals derived simultaneously from receiving aerials or aerial systems having differently-oriented directivity characteristics G01S3/30derived directly from separate directional systems G01S3/32derived from different combinations of signals from separate aerials G01S3/325Automatic tracking systems G01S3/34the separate aerials comprising one directional aerial and one non-directional aerial G01S3/36the separate aerials having differently-oriented directivity characteristics G01S3/38using adjustment of real or effective orientation of directivity characteristic of an aerial or aerial system to give a desired condition of signal derived from that aerial or aerial system G01S3/40adjusting orientation of a single directivity characteristic to produce maximum or minimum signal G01S3/42the desired condition being maintained automatically G01S3/44the adjustment being varied periodically or continuously until it is halted automatically when the desired condition is attained G01S3/46using aerials spaced apart and measuring frequency phase or time difference between signals therefrom G01S3/465the waves arriving at the aerials being frequency modulated and the frequency difference of signals therefrom being measured G01S3/48the waves arriving at the aerials being continuous or intermittent and the phase difference of signals derived therefrom being measured G01S3/50the waves arriving at the aerials being pulse modulated and the time difference of their arrival being measured G01S3/52using a receiving aerial moving, or appearing to move, in a cyclic path to produce a Doppler variation of frequency of the received signal G01S3/54the apparent movement of the aerial being produced by coupling the receiver cyclically and sequentially to each of several fixed spaced aerials G01S3/56Conical-scan beam systems using signals indicative of the deviation of the direction of reception from the scan axis G01S3/58Rotating 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 G01S3/60Broad-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 G01S3/62wherein the phase angle of the signal is indicated by a cathode-ray tube G01S3/64wherein the phase angle of the signal is determined by phase comparison with a reference alternating signal varying in synchronism with the directivity variation G01S3/66Narrow-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 th... G01S3/68wherein the timing of the pulse-type envelope signal is indicated by cathode-ray tube G01S3/70wherein 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 G01S3/72Diversity systems specially adapted for direction-finding G01S3/74Multi-channel systems specially adapted for direction-finding G01S3/78using electromagnetic waves other than radio waves G01S3/7803Means for monitoring or calibrating G01S3/7806using gamma or X-rays G01S3/781Details G01S3/782Systems for determining direction or deviation from predetermined direction G01S3/783using amplitude comparison of signals derived from static detectors or detector systems G01S3/7835using coding masks G01S3/784using a mosaic of detectors G01S3/785using 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 G01S3/786the desired condition being maintained automatically G01S3/7861Solar tracking systems G01S3/7862mounted on a moving platform G01S3/7864T.V. type tracking systems G01S3/7865using correlation of the live video image with a stored image G01S3/7867Star trackers G01S3/7868using horizon sensors G01S3/787using rotating reticles producing a direction-dependant modulation characteristic G01S3/788producing a frequency modulation characteristic G01S3/789using rotating or oscillating beam systems G01S3/80using ultrasonic, sonic or infrasonic waves G01S3/8003Diversity systems specially adapted for direction finding G01S3/8006Multi-channel systems specially adapted for direction-finding G01S3/801Details G01S3/802Systems for determining direction or deviation from predetermined direction G01S3/8022using the Doppler shift introduced by the relative motion between source and receiver G01S3/8025Conical-scan beam systems using signals indicative of the deviation of the direction of reception from the scan axis G01S3/8027By vectorial composition of signals received by plural, differently-oriented transducers G01S3/803using amplitude comparison of signals derived from receiving transducers or transducer systems having differently-oriented directivity characteristics G01S3/8032wherein the signals are derived sequentially G01S3/8034wherein the signals are derived simultaneously G01S3/8036derived directly from separate directional systems G01S3/8038derived from different combinations of signals from separate transducers comparing sum with difference G01S3/805using adjustment of real or effective orientation of directivity characteristic of a transducer or transducer system to give a desired condition of signal derived from that transducer or transducer system G01S3/8055adjusting orientation of a single directivity characteristic to produce maximum or minimum signal G01S3/807the desired condition being maintained automatically G01S3/808using transducers spaced apart and measuring phase or time difference between signals therefrom G01S3/8083determining direction of source G01S3/8086determining other position line of source G01S3/809Rotating 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 G01S3/82with means for adjusting phase or compensating for time-lag errors G01S3/84with indication presented on cathode-ray tubes G01S3/86with means for eliminating undesired waves