Systems using the reflection or reradiation of acoustic waves

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

G01S15/00Systems using the reflection or reradiation of acoustic waves

G01S15/003Bistatic sonar systems; Multistatic sonar systems G01S15/006Theoretical aspects G01S15/02using reflection of acoustic waves G01S15/025Combination of sonar systems with non-sonar or non-radar systems G01S15/04Systems determining presence of a target G01S15/06Systems determining the position data of a target G01S15/08Systems for measuring distance only G01S15/10using transmission of interrupted pulse-modulated waves G01S15/101Particularities of the measurement of distance G01S15/102using transmission of pulses having some particular characteristics G01S15/104wherein the transmitted pulses use a frequency- or phase-modulated carrier wave G01S15/105using irregular pulse repetition frequency G01S15/107using frequency agility of carrier wave G01S15/108using more than one pulse per sonar period G01S15/12wherein the pulse-recurrence frequency is varied to provide a desired time relationship between the transmission of a pulse and the receipt of the echo of a preceding pulse G01S15/14wherein a voltage or current pulse is initiated and terminated in accordance respectively with the pulse transmission and echo reception G01S15/18wherein range gates are used G01S15/32using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves G01S15/325using transmission of coded signals G01S15/34using transmission of frequency-modulated waves and the received signal, or a signal derived therefrom, being heterodyned with a locally-generated signal related to the contemporaneous transmitted signal to give a beat-frequency signal G01S15/36with phase comparison between the received signal and the contemporaneously transmitted signal G01S15/42Simultaneous measurement of distance and other co-ordinates G01S15/46Indirect determination of position data G01S15/50Systems of measurement, based on relative movement of the target G01S15/52Discriminating between fixed and moving objects or between objects moving at different speeds G01S15/523for presence detection G01S15/526by comparing echos in different sonar periods G01S15/58Velocity or trajectory determination systems Sense-of-movement determination systems G01S15/582using transmission of interrupted pulse-modulated waves and based upon the Doppler effect resulting from movement of targets G01S15/584with measures taken for suppressing velocity ambiguities G01S15/586using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves and based upon the Doppler effect resulting from movement of targets G01S15/588measuring the velocity vector G01S15/60wherein the transmitter and receiver are mounted on the moving object G01S15/62Sense-of-movement determination G01S15/66Sonar tracking systems G01S15/74Systems using reradiation of acoustic waves, e.g. IFF G01S15/87Combinations of sonar systems G01S15/872Combination of several systems for attitude determination G01S15/874Combination of several spaced transponders or reflectors of known location for determining the position of a receiver G01S15/876Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S15/878wherein transceivers are operated, either sequentially or simultaneously, both in bi-static and in mono-static mode G01S15/88Sonar systems specially adapted for specific applications G01S15/885Meteorological systems G01S15/89for mapping or imaging G01S15/8902Side-looking sonar G01S15/8904using synthetic aperture techniques G01S15/8906Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques G01S15/8909using a static transducer configuration G01S15/8911using a single transducer for transmission and reception G01S15/8913using separate transducers for transmission and reception G01S15/8915using a transducer array G01S15/8918the array being linear G01S15/892the array being curvilinear G01S15/8922the array being concentric or annular G01S15/8925the array being a two-dimensional transducer configuration G01S15/8927using simultaneously or sequentially two or more subarrays or subapertures G01S15/8929using a three-dimensional transducer configuration G01S15/8931co-operating with moving reflectors G01S15/8934using a dynamic transducer configuration G01S15/8936using transducers mounted for mechanical movement in three dimensions G01S15/8938using transducers mounted for mechanical movement in two dimensions G01S15/894by rotation about a single axis G01S15/8943co-operating with reflectors G01S15/8945using transducers mounted for linear mechanical movement G01S15/8947using transducers movable by (electro)magnetic means G01S15/895characterised by the transmitted frequency spectrum G01S15/8952using discrete, multiple frequencies G01S15/8954using a broad-band spectrum G01S15/8956using frequencies at or above 20 MHz G01S15/8959using coded signals for correlation purposes G01S15/8961using pulse compression G01S15/8963using pulse inversion G01S15/8965using acousto-optical or acousto-electronic conversion techniques G01S15/8968using acoustical modulation of a light beam G01S15/897using application of holographic techniques G01S15/8972with optical reconstruction of the image G01S15/8975using acoustical image/electron beam converter tubes G01S15/8977using special techniques for image reconstruction G01S15/8979Combined Doppler and pulse-echo imaging systems G01S15/8981Discriminating between fixed and moving objects or between objects moving at different speeds G01S15/8984Measuring the velocity vector G01S15/8986with measures taken for suppressing velocity ambiguities G01S15/8988Colour Doppler imaging G01S15/899Combination of imaging systems with ancillary equipment G01S15/8993Three dimensional imaging systems G01S15/8995Combining images from different aspect angles G01S15/8997using synthetic aperture techniques G01S15/93for anti-collision purposes G01S15/931between land vehicles; between land vehicles and fixed obstacles G01S15/96for locating fish