Abstract: A seismic data collection unit having multiple separate geophones/geophone packages positioned in a housing wherein the geophones are offset from a vertical axis so that summing of the geophones' respective outputs minimizes certain noise in the unit's output. Specifically, the offset geophones are physically positioned or mathematically configured so as to be symmetrical about a selected vertical axis in order to cancel out certain noise in a seismic signal. The particular placement of the geophones within the housing is preferably selected so that the vertical axis around which the geophones are positioned passes through the center of gravity of the unit.

Abstract: A method and a downhole telemetry system a downhole telemetry system using discrete multitone modulation for transmitting a data stream over a plurality of transmission modes is provided. The downhole telemetry system includes a downhole transmitter, a cable, and a surface receiver. The downhole transmitter is configured to transmit the data stream over the plurality of transmission modes. The surface receiver is coupled to the downhole transmitter via the cable and is configured to combine signals from each of the plurality of transmission modes to obtain the data stream transmitted by the downhole receiver. The method includes receiving a plurality of signals over the plurality of transmission modes from a downhole package, and may further include combining the plurality of signals to form at least one data stream.

Abstract: In the present invention, a seismic receiver contains an onboard digitizer that samples and converts a signal from detected seismic energy into the digital domain. The receiver contains an analog to digital converter, a transmission circuitry, and a link to the seismic detection circuitry. The signal from the seismic detection circuitry is converted into a digital signal, which is then relayed to the data recorder. These components are all resident to the receiver itself. Additional control circuitry is employed to provide clocking and testing functions. These receivers communicate with one another, and provide sampled seismic data on an individual basis. The components may be prepared on a PCB and put inside the receiver cap. The PCB may be flexible in nature, as to provide a maximum of surface mounted components in the smallest amount of space.

Abstract: A device for sensing seismic and/or acoustic vibrations, has a body of a particulate material composed of a plurality of individual particles, and a system for determining changes in electrical conductivity of the particulate material caused by seismic and acoustic vibrations.

Abstract: A seismic sensor, has a case, a pre-charged, non-conductive membrane located between two plates that form a capacitor and accommodated inside the case, with one of the plates being immovable relative to the case and the other of the plates being movable relative to the one plate under the action of seismic activity of a medium in which the sensor is located, so that the capacitor produces an electrical signal responsive to the seismic activity, and a mass increasing element associated with the movable plate so as to increase mass of the movable plate and therefore enhance oscillations of the movable plate under the action of the seismic activity.

Abstract: A seismic sensor, comprising a case, a pre-charged, non-conductive membrane located between two plates that form a capacitor and accommodated inside the case, with one of the plates being immovable relative to the case and the other of the plates being movable relative to the one plate under the action of seismic activity so that the capacitor produces an electrical signal responsive to the seismic activity of a medium in which the sensor is located, and a mass increasing element associated with the movable plate so as to increase mass of the movable plate and therefore to enhance oscillations of the movable plate under the action of the seismic activity, the mass increasing element being formed as a further case which is connected to the movable plate and is located in condition of equilibrium in an inoperative position of the sensor.

Abstract: A back plate having a stationary back electrode is secured to a substrate. A diaphragm electrode is mounted on the back plate interposing a spacer. A frame having a sound collecting hole is mounted on the diaphragm electrode.

Abstract: A microphone is constructed to be more tolerant to a wide range of relative humidity conditions without adversely affecting the performance of the microphone. The microphone includes a housing with a sound port for receiving sound and an electret assembly for converting the sound into an output signal. The electret assembly includes a diaphragm and a backplate. The backplate is made of at least two layers, usually polymeric layers. The first layer of material has a first hygroscopic coefficient and a second layer of material has a second hygroscopic coefficient. The first and second layers cause the backplate to bend in response to higher humidity conditions, thereby minimizing the adverse effects on microphone performance caused by characteristic changes in the diaphragm at the higher humidity conditions.

Abstract: A geophone including conductive terminals positioned on opposite sides of the geophone housing. The geophone includes a pair of coils resiliently mounted within the geophone housing and a magnet. A first end plate, a first spring, and a first coil support provide a first end of the electrically conductive path. A second end plate, a second spring, and a second coil support provide a second end of the electrically conductive path. The first and second end of the electrically conductive path are electrically insulated from each and the geophone housing. Providing one or more remaining components with electrically non-conductive surfaces provides electrical insulation.

Abstract: A sensor for detecting and monitoring scour in sediment positioned beneath a body of water, which includes a probe at least partially embedded in the sediment. Sensor electronics are superimposed on the probe. Such electronics include a reflectometer, a battery supply and a telemetry transmitter to display an interface boundary between the water and the transmitter. The sensor is particularly well adapted for use in lossy soils.

Abstract: A system for rejecting wind noise at a plurality of sensors includes input logic, a processor and output logic. The input logic receives a signal from each of the plurality of sensors. The processor assigns a weight value to each of the received signals. The output logic derives a wind noise rejected output signal based on a function of the assigned weight values and the received signals.

Abstract: To provide the POS server which can respond immediately against request from local terminals, the POS server 100 according to this invention, which controls dealings of products at a plurality of stores, includes a plurality of control apparatuses 210 connecting with a plurality of local terminals 300 provided at a plurality of stores. Each of the plurality of control apparatuses 210 a dealing database 116 storing information of dealings of the products at the local terminals 300, a receiving device 152 receiving the database operating instruction for updating the dealing database 116 with the dealing of the products from the local terminal 300, and a database updating device 162 updating the dealing database 116 according to the received database operating instruction. Each receiving device 152 of the plurality of control apparatuses 210 receives the same database operating instruction which is transmitted to the control apparatuses from the local terminal 300.

Abstract: The invention provides an instrument suitable for measuring seismic waves in an environment which comprises a wave guide through which a seismic wave may propagate substantially without dispersion wherein the wave guide is provided with means for measuring its deformation.

Abstract: The invention provides method and apparatus that utilize a plurality of port sub-arrays, in which each port sub-array comprises a plurality of acoustical ports. The ports of each port sub-array are spaced so that each port sub-array responds to acoustical signals that are generated by acoustical sources within an associated frequency range. In an embodiment of the invention, associated frequency ranges are related in a harmonic manner, in which each port sub-array corresponds to different frequency octaves. The associated frequency range is a portion of the total frequency range of an acoustical system. Received acoustical signals from each of the port sub-arrays are coupled over acoustical pathways and are converted into electrical signals by capsules that may be mounted in a capsule mounting. The electrical signals may be filtered, such as to reduce spatial aliasing, and post processed to further enhance the characteristics of the signals.

Abstract: Although normal microphones are very cheap, their range is usually limited up to around 10 KHz and is typically not free from various distortions. Other microphones that can reach 20 KHz or close to it typically cost tens or hundreds of dollars and still have various limitations, and higher-end microphones, for example of the types needed for Live Music performance or for the Mass media broadcasting, such as for example Radio or TV, are typically much more expensive and can cost even thousands of dollars. The main reason for these limitations is the fact that normal Microphones use a membrane, which is a mechanical element, and therefore they are limited by the mechanical qualities of the membrane. The present invention solves this problem by using a high quality Membrane-less Microphone capable of functioning in a very wide range of frequencies without distortions, which can be at the same time very compact and much cheaper than the state-of-the-art high-end microphones.

Abstract: A back plate having a stationary back electrode is secured to a substrate. A diaphragm electrode is mounted on the back plate interposing a spacer. A frame having a sound collecting hole is mounted on the diaphragm electrode.

Abstract: The invention provides method and apparatus that utilize a plurality of port sub-arrays, in which each port sub-array comprises a plurality of acoustical ports. The ports of each port sub-array are spaced so that each port sub-array responds to acoustical signals that are generated by acoustical sources within an associated frequency range. In an embodiment of the invention, associated frequency ranges are related in a harmonic manner, in which each port sub-array corresponds to different frequency octaves. The associated frequency range is a portion of the total frequency range of an acoustical system. Received acoustical signals from each of the port sub-arrays are coupled over acoustical pathways and are converted into electrical signals by capsules that may be mounted in a capsule mounting. The electrical signals may be filtered, such as to reduce spatial aliasing, and post processed to further enhance the characteristics of the signals.

Abstract: A device for sensing seismic and/or acoustic vibrations, has a body of a particulate material composed of a plurality of individual particles, and a system for determining changes in electrical conductivity of the particulate material caused by seismic and acoustic vibrations.

Abstract: A system for gathering and recording seismic data. The system provides cable sections having takeouts at predetermined locations for connection to a string data module and attached sensor string. Additional data strings can be connected to vary the sensor orientation and spacing at different positions within a seismic array. Data is collected by sensors attached to each sensor string and is transmitted through the corresponding string data module and to an intermediate data manager. The data is transmitted at a high delivery rate to a master recording unit. Transverse data managers can be connected in large arrays between intermediate data managers and the master recording unit to provide additional control or data processing attributes, and local recorders can provide data processing and transmission attributes before the data is transmitted to the master recording unit. The system architecture contains multiple levels of data paths each having successively higher data rates.

Abstract: Seismic wave reception device comprising a hydrophone and/or a geophone and method for coupling it (or them) with a solid medium such as the subsoil. The device comprises at least one hydrophone (2) immersed in a closed flexible-walled sheath (7) filled with liquid (8) that is closed at one end by a sealed plug (9) provided with a sealed duct for a cable (10) connecting the hydrophone to a signal acquisition means (E). The sheath is arranged in a cavity (6) and tightly coupled with medium (5) substantially over the total surface thereof, preferably by means of a hardenable material such as cement. A geophone can be placed in the same coupling material in the vicinity of sheath (7) containing hydrophone (2). Application: seismic prospecting or monitoring operations in an underground formation, notably in order to discriminate the seismic upgoing and downgoing waves.

Abstract: An apparatus for detecting an underground abject includes a container in contact with the ground surface; a medium disposed in the container; at least one acoustic sensor disposed in the medium in the container; and an output device connected to the acoustic sensor. A portion of the container in contact with the ground is substantially acoustically transparent and conforms to contours of the ground. The acoustic impedance of the medium in the container is substantially the same as the acoustic impedance of the ground. A method of detecting an underground object includes receiveing reflected acoustic noise with at least one acoustic sensor immersed in a medium, the mediukm being desposed in a container in contact with a ground surface; converting the reflected acoustic noise to electrical signals; and, using an output device, converting teh eletrical signals to a form that can be sensed by a human to determine if the undergroung object has been detected.

Abstract: The opto-acoustic generator of ultrasound waves comprises an optical fiber associated to a laser-energy source, and an opto-acoustic transducer which is applied to said fiber and is designed to be impinged upon by the laser beam and to absorb partially the energy, converting it into thermal energy, thus bringing about the formation of ultrasound waves by the thermo-acoustic effect. Said opto-acoustic transducer consists of a layer or film containing prevalently graphite, which is applied on a surface of said optical fiber.

Abstract: The invention provides an instrument (1) suitable for measuring seismic waves (7) in an environment (2) which comprises a wave guide (3, 4 and 5) through which a seismic wave may propagate substantially without dispersion wherein the wave guide is provided with means for measuring its deformation (6a, 6b, 6c and/or 6d).

Abstract: A micro-machined ultrasonic transducer (MUT) having aperture, elevation and apodization controlled by apparatus located on the same substrate as the transducer, or by bias voltage control applied to MUT elements, allows for an efficient and compact ultrasonic probe. The control apparatus may take the form of field effect transistors (FET's), micro-machined relays, or doped regions on the substrate, or any other apparatus that may be located on the same substrate as that of the transducer, or by bias voltage sources connected to the MUT elements.

Abstract: An ultrasound sensor has a housing, a piezoelectric ceramic element and a plurality of isolating layers received in the housing. The housing has a tapered rectangle chamber defined therein for receiving the piezoelectric ceramic element. The tapered rectangle chamber has a unique shape which is able to limit the shape of the emitted ultrasound signal by the piezoelectric ceramic element. The limited range of the ultrasound signals emitted by the piezoelectric ceramic element covers the entire cross section of the vehicle and will not cause a false alarm by reflection from the ground.

Abstract: A method for the study of elastic wave phenomena in the ground, where the detection of said phenomena is carried out with the use of at least a geophone comprising at least a couple of transducers (20, 21; 37, 38), each transducer (20, 21; 37, 38) being apt to detect horizontally polarized shear waves, represented by SH signals, and compression waves, represented by P signals.

Abstract: A seismic sensor unit (10) comprises a case (12) containing electronic circuits (18, 20) that serve to digitise and digitally process the output signals of a seismic sensor element (16) inside the case (12). A first digital filtering of acquired signals can be provided at sensor unit level before the data are further fed into a seismic network and further processed.

Abstract: An improved method and apparatus are provided for improving a coupling to a substrate and orientation of seismic receivers such as a geophone to a substrate for the analysis and gathering of seismic data.

Abstract: An apparatus and a method for anchoring a seismic geophone to soil. The apparatus comprises a base having a base section for engagement with the geophone. The base also has an anchor end attachable to the soil to restrict movement of the geophone after said base section is engaged with the geophone and after said anchor end is attached to the soil. A latch can detachably secure the base section to the geophone or to a seismic cable attached to the geophone, and the base can comprise a biodegradable material. The method of the invention attaches the base anchor end to the soil so that the base section engages the geophone to restrict movement of the geophone from the desired location relative to the soil.

Abstract: An ultrasound sensor for distance measurement is disclosed. The ultrasound sensor has a housing, a ceramic buzzer, a plurality of isolators both received in the housing and a C ring for securing the plurality of isolators in the housing. The housing has an elliptical and a circular compartments defined therein. The elliptical compartment communicates with the circular compartment and both have a unique shape, which is able to limit the shape of the emitted signal by the ceramic buzzer. The limited range of the emitted signal by the ceramic buzzer covers the entire cross section of the vehicle and will not cause a false alarm by reflection from the ground.

Abstract: Acoustic intensity is measured by a submerged probe consisting of two passive geophones mounted in spaced relationship with their sensing axes aligned. The geophones are connected through a cable to a remote spectrum analyzer in which acoustic intensity is computed from the velocity gradient between the two geophones. The exclusive use of geophones, which inherently have low impedance outputs, eliminates the need for preamplification in the probe. The geophones are mounted inside an acoustically transparent, thin rubber shell, which reduces the effects of noise due to flow.

Abstract: A molded protective body member for seismic cable hydrophone and geophone sensors and their cable splice connections from underwater obstructions and pay-out and retrieval apparatus. The body member is a one piece polymeric member having interior cavities, risers and apertures. When in use, the body member is folded longitudinally in half around the seismic cable at a hydrophone or geophone splice joint and secured in place with recessable molded straps having threaded fasteners passing through each of the body halves thus clamping the body to the cable. At least one interior diametrical cavity is provided consistent with the type seismic cable sensor used. With the sensor and its associated cable and connector positioned within the protective body member, tie wraps are threaded through apertures along and adjacent the longitudinal edges of each half thus closing the interior of the body member. Cavities are also provided internally for placing lead weights.

Abstract: A method for monitoring production mineral reservoirs, the method comprising: permanently installing a geophone in a borehole; generating a first set of seismic waves; receiving a first set of seismic data with the geophone; recording the first set of data of said receiving a first set of seismic data; generating a second set of seismic waves after sufficient time has passed for conditions in the reservoir to have changed from the generating a first set of seismic waves; receiving a second set of seismic data with the geophone; and recording the second set of seismic data of said receiving a second set of seismic data. A method for installing instruments below the surface of the earth, the method comprising: drilling a borehole with a drill apparatus; inserting an instrument in the borehole; and permanently fixing the instrument in the borehole.

Abstract: A seismic acquisition system and method utilizing an array of buried geophones storage devices or containers (16) each having a geophone (40) which may be permanently stored in container (16) in a fluid tight relation. The storage container (16) includes a base (26), a tubular cylindrical body (28), and an upper cap (32) threaded onto body (28). The storage container (16) is shown in FIG. 2 in an operable relation and in FIG. 3 with geophone (40), lead (52), and connector (54) in a stored relation. In the event an additional survey or shoot is conducted at a later time, such as a one year time interval, the buried storage containers (16) are utilized upon removal of outer caps (32) and withdrawing of geophone connectors (54) for connection in a mating relation to cable connectors (20).

Abstract: A repairable geophone housing having a fully molded waterproof one piece upper body which is seabably and releasably connectible to a lower body. All surfaces within the upper body are bonded to prevent moisture entering and the geophone transducer may be replaced if desired.

Abstract: A cart-mounted acoustic transmitter and receiver system for echo-locating underground structures, such as piping. A transmitting transducer, mounted in a non-resonant tube and positioned adjacent to the ground, directs sound waves downwardly through an air column while a receiving transducer, rolling over the ground, picks up echoes returned from buried objects. The rolling transducer includes a piezo-electric transducer mounted in a tubular plastic axle on which an elastomeric disc rotates making contact with the ground. A pair of port and starboard rolling transducers provide inputs to a differential amplifier to enhance detection by increasing discrimination against the return from the benign land mass.

Abstract: An acceleration sensor is based on a semiconductor technique which is suitable for mass production. The resulting acceleration sensor is small in size and high in precision. The acceleration sensor includes a stationary section, an acting section to which a force is applied in response to acceleration, a flexible section through which the stationary section is coupled to the acting section, a plurality of distortion sensing elements coupled to the flexible section, a first weight having a bottomed hole which is gradually smaller in width towards the bottom of the hole, the first weight being coupled to the acting section and a second weight, greater in specific gravity than the first weight, coupled to the bottom of the hole of the first weight.

Abstract: A roll or tilt responsive switch includes a housing formed from an electrically conductive material and having an inclined face formed on the bottom to gradually rise concentrically outwardly substantially from the center of the bottom, and a header fixed to the housing to close its open end and having a through-aperture in which a terminal pin is fixed in an insulated relation. A contact is fixed to an end of the terminal pin located inside the housing and has a plurality of feather portions each having a predetermined elasticity and disposed concentrically with the terminal pin. An inertia ball is enclosed in the housing to be located substantially at the center in the housing in a normal position of the switch in a stationary state.

Abstract: The objective of this invention is to simplify and provide a versatile device capable of accurately measuring seismic activity. The technique is based on magnetic levitation. The concept of magnetic levitation has been around since the 1960's, and it has been used extensively for high speed trains, however its use in seismology has been described in U.S. Pat No. 3,626,364 issued to Simon et al. However the present invention utilizes a four-vector magnetic field instead of three separate scalar magnetic fields. The advantages of present approach is reduction of three seismic masses to a single seismic mass.To detect seismic activity using this concept, a seismic mass must be magnetically suspended. A seismic mass trapped in a magnetic field still possesses its inertia. Therefore, as the magnetic field moves under the influence of seismic activity, the seismic mass will tend to stay in the same place. The controller, however tends to keep the seismic mass in its place.

Abstract: The device comprises instruments for collection and recording of signals in seismic exploration of the substratum off-shore. The device is designed as a pole which is adapted to be forced down into the seabed and comprises a pointed lower end (7), an intermediate approximately cylindrically shaped main portion (6), a vibration-absorbing spacer (14) between the pointed end (7) and the intermediate main portion (6). The other end of the intermediate main portion (6) is connected to a top part (8) designed for inserting/pulling and other ways of handling the device. The pointed end (7) at least comprises geophones (15-17) and a hydrophone (23) is placed in the vicinity of the upper end of the device. The majority of the device's other instruments are placed in the intermediate main portion (6). The device is connected to a main cable (4) which extends to a seismic ship (29, 31).

Abstract: A seismic switching device that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period.

Abstract: A device detects seismic motion by linear motion of a seismic detection ball within an inner casing. Radial protrusions on the inside surface of a bottom wall of the inner casing maintain linear back-and-forth motion of the seismic detection ball while in contact with the casing bottom wall. On the inside surface of the perimeter wall of the inner casing, radially inward protrusions are formed parallel to one another to prevent rotation of the seismic detection ball in a circular path along the casing perimeter when it is lifted up from the casing bottom wall. The seismic detection ball is formed from a material unaffected by magnetic fields. The inner casing is suspended within an outer casing, in a condition of damped swaying. The inner casing is composed at least partially of a metallic material to provide sufficient weight to insure reliable automatic centering.

Abstract: An underwater probe for determining true acoustic intensity by the direct asurement of true acoustic velocity and true acoustic pressure in a neutrally buoyant package, utilizes a moving-coil geophone embedded in a casting of syntactic foam and a pair of hydrophones on the exterior of the casting.

Abstract: A sensor for detecting acoustic energy emitted by a target is disclosed. The sensor comprises a housing including a plurality of transducers for receiving acoustic energy. The transducers are randomly deployed within a predetermined area around the housing, forming an array and a self-survey technique is utilized to determine the positions of the sensors. Beamforming techniques are utilized to analyze the acoustic energy detected by the transducers to provide the azimuth of a target and a class estimate of the target. A plurality of sensors may be utilized to provide target location, course and velocity.

Abstract: A seismic sensor platform comprises an open frame and a plurality of seismic motion sensors vertically positioned in a common horizontal plane in spaced relationship around the periphery of the open frame. A spike associated with each of the sensors extends beneath the open frame for anchoring each of the sensors in the earth. The frame includes a shield for protecting the sensors from physical damage and for shielding them from seismic noise. Second and third pluralities of horizontally positioned sensors may be provided on the frame, orthogonally positioned with respect to each other to sense orthogonal components of reflected seismic waves. The sensors may each be of a different natural frequency to optimize the multi frequency output of the sensor array.

Abstract: Doping the jacket of a data cable reduces the bulk volume resistivity of the jacket material allowing built-up static electricity to discharge. This reduces the likelihood of static charge interfering with data transmission.

Abstract: In a preferred embodiment, an accelerometer sensor system, including: a housing structure; a first acceleration sensor disposed in the housing structure at a first selected location along the vertical axis of the housing structure, the first acceleration sensor providing a first output; a second acceleration sensor disposed in the housing structure at a second selected location along the vertical axis, the second acceleration sensor providing a second output; and apparatus to combine the first and second outputs of the first and second acceleration sensors such as to simulate the output from a virtual acceleration sensor located at any selected location on the vertical axis, allowing one to reduce noise induced by pitch motion, at any desired frequency or across a desired frequency band.

Abstract: A remote sensing system is provided which operates as a bipolarized, differential mode, LDI (laser differential interferometry) system to detect motion at a remote location. The system is adapted to reduce the effects of turbulence induced frequency fluctuations by using a retroreflector apparatus which converts a single sensing beam into a single return beam having two overlapping transversely polarized sensing signals; thus, turbulence induced noise will be common mode to both return signals and cancel at the receiver. In preferred embodiments, the system is used to detect seismic motions. The retroreflector apparatus is coupled to ground motions at a selected location where it separates the sensing beam into two polarized sensing signals, frequency modulates one of the polarized sensing signals to contain frequency components that represent selected ground motions, and combines the polarized sensing signals into the return beam. The return beam is detected.

Abstract: A device including instruments for use on the seabed for the collection and recording of first signals during off-shore seismic exploration.

Abstract: The system is a remotely operated, autonomous multi-channel time history recording device which uses digital and computer technologies to detect, record and display the results of tests that are time varying dependent. It is particularly suited to monitoring the effects of exploding warheads. By placing a series of piezoelectric detectors in an exploding shock wave field, it is possible to ascertain the wavefront propagation. A dynamic peak detector is used is used with each piezoelectric detector to detect the exact peak of the unknown pulse which peak defines the "time-of-arrival" of the pulse. By controlling the system with a computer program it is possible to display the complete time history of the propagating shock wave. When the exploding device is detonated a counter increments in 100 ns steps with its output on a timing bus.