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公开(公告)号：EP1378079B1
公开(公告)日：2011-01-05
申请号：EP02720146.6
申请日：2002-03-28
发明人： DAVIES, Jonathan James, QinetiQ Ltd. , DUNN, Shaun Michael, QinetiQ Ltd. , POINTER, Stephen Arthur, QinetiQ Ltd. , DOWNER, Samuel William, QinetiQ Ltd.
IPC分类号： H04B13/02
CPC分类号： H04B11/00 , H04B13/02 , H04J13/0029 , H04J13/12 , H04L1/0057 , H04L27/103
摘要： For digital underwater transmission an information sequence (17) of digital bits is partitioned into a succession of symbols each comprising n bits where n is equal to or greater than one (2n potential symbols), each symbol (19) is replaced (20) with a corresponding base code sequence of length m bits and the result (21) is passed to an acoustic transducer after bi-phase modulation (22) on a carrier. The code has good correlation properties, e.g. a pseudo-random maixmal length sequence, a Gold code or a Kasami code, and the value of m/n is at least (32). Preferably the base sequence is cyclically extended at one or both ends prior to modulation, and Solomon Reed redundancy coding (18) is initially applied to the information sequence. The output (23) of modulator (22) may be prefaced (26) by a pair of chirp waveforms (24). Provision is made for Doppler and multi-path correction.
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公开(公告)号：EP2744704B1
公开(公告)日：2019-06-26
申请号：EP12753563.1
申请日：2012-08-07
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公开(公告)号：EP1481225B1
公开(公告)日：2012-08-15
申请号：EP03712306.4
申请日：2003-03-03
发明人： WESTHALL, Jonathan, James Qinetiq Limited , HILL, David, John Qinetiq Limited , BABB, William, Malcolm Qinetiq Limited , NASH, Philip, John Qinetiq Limited , THOMSON, Steven, Robert Qinetiq Limited
摘要： An optical sensor assembly comprising a plurality of optical fibre sensor coils optically coupled by optical fibre; and an elongate support element, on which said plurality of optical fibre sensor coils and optically coupling optical fibre are mounted is disclosed. The support element has an elastic limit such that when said support element is bent away from the elongate axis, the optical fibre fracture limit is reached before the elastic limit is reached. An array of these optical sensor assemblies, the mandrel on which the sensing coils are mounted and their method of manufacture are also disclosed.
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4.发明授权CONTROL DEVICE FOR CONTROLLING THE POSITION OF A MARINE SEISMIC STREAMER 有权控制装置一POSITIONSSTEUERRUNG MEERESSEIMISCHEN MESS CABLE
公开(公告)号：EP1407225B1
公开(公告)日：2011-12-07
申请号：EP02735661.7
申请日：2002-07-02
IPC分类号： G01V1/38
CPC分类号： G01V1/3826
摘要： A control device (1) for controlling the position of a marine streamer comprising; an annular aerofoil (2), a mount (3) for mounting the annular aerofoil onto and around the streamer; and control means (4a, 4b) for controlling the tilt and/or rotation of the annular aerofoil(2) whereby to adjust the lateral position and/or depth of the streamer.
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公开(公告)号：EP3030355A1
公开(公告)日：2016-06-15
申请号：EP14761390.5
申请日：2014-08-11
发明人： HARDIE, David
IPC分类号： B06B1/06
CPC分类号： B06B1/0614 , B06B1/0633 , B06B1/0655 , B06B2201/74
摘要： A system for producing sound waves in a medium, the system comprising: at least two first free-flooded ring transducers (100) centred about a first axis, the first free-flooded ring transducers (100) being substantially cylindrical and having an axial gap of height g therebetween such that they form a first column; and at least one cylindrical body (500a, 500b) centred about the first axis nested in the first column, such that the cylindrical body is aligned with the axial gap. The cylindrical body may be a tweeter free-flooded ring transducer. This provides for improved wideband performance in a free flooded ring array.
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公开(公告)号：EP2744704A1
公开(公告)日：2014-06-25
申请号：EP12753563.1
申请日：2012-08-07
发明人： POINTER, Stephen , PURNELL, Daryl
CPC分类号： B63B22/18 , B63B22/003
摘要： A communication buoy launched from an underwater craft or installation comprising remote radio communications in a surface module and acoustic communications in a submergible module, wherein the entire hermetically sealed buoy ascends to the surface after launch under its own positive buoyancy, deploys flotation means at the surface, then separates the modules wherein the submergible module partially floods, becomes negatively buoyant and descends to a predetermined depth on an umbilical communication cable that connects the modules together. The sonobuoy may be launched from a submarine with its centre of mass above its centre of buoyancy so that it rights itself after launch until the centre of mass is below the centre of buoyancy during ascent. A control means may trigger deployment of a flotation bag with an antenna after a predetermined time. The module separation may occur after a second predetermined time or once a GPS fix is achieved using the antenna. A drogue, spool, and cable damping may prevent the modules uncoupling after the submergible module descends. A ring transducer may be used for transmitting and receiving acoustic communications.
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公开(公告)号：EP2198539A1
公开(公告)日：2010-06-23
申请号：EP08788408.6
申请日：2008-08-26
CPC分类号： H04B11/00 , G01S3/8083
摘要： A method of underwater communication between a link initiator and a link receptor, by transmitting a link acquisition waveform from the initiator to the receptor, and establishing communications channel parameters from such a received waveform. Data is then transmitted according to these parameters, which may include range, direction, frequency band and Doppler, with greater efficiency and robustness.
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