Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A clock oscillator includes a first crystal controlled oscillator, a second crystal controlled oscillator and a logic controller functionally coupled to the first and second crystal controlled oscillators. The logic controller is programmed to calculate a frequency of the first crystal controlled oscillator as a function of the frequency of the first crystal controlled oscillator with respect to a frequency of the second crystal controlled oscillator characterized with respect to an environmental parameter.

Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A seismic sensing module comprises a seismic sensing element and a processor configured to generate a test signal applied to the seismic sensing element, receive a response from the seismic sensing element, and determine a characteristic of the seismic sensing module according to the response.

Abstract: Implementations of various technologies for a method for establishing communication pathway redundancy within a seismic recording array. In one implementation, the method may include identifying each data acquisition cell deployed in a seismic field and determining one or more communication pathways for each data acquisition cell. The communication pathways include a primary communication pathway and at least one backup communication pathway toward a data collection unit.

Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock.

Abstract: An apparatus and method for collecting data acquired during a seismic survey are disclosed. The apparatus is a seismic survey system, comprising a plurality of data sources, a plurality of cells, and a plurality of independent pathways. The data sources are positioned about an area to be surveyed, each data source being associated with a transmitter capable of transmitting data. The cells each contain a portion of the data sources and their associated transmitters. One of the transmitters within each cell also serves as a gateway for receiving data transmitted from the other data source transmitters within the cell. The independent pathways each contain a portion of the gateways whereby data may be transmitted along each pathway via the gateways and associated transmitters in that pathway. The method is a method for conducting a seismic survey.

Abstract: Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Implementations of various technologies for a method for establishing communication pathway redundancy within a seismic recording array. In one implementation, the method may include identifying each data acquisition cell deployed in a seismic field and determining one or more communication pathways for each data acquisition cell. The communication pathways include a primary communication pathway and at least one backup communication pathway toward a data collection unit.

Abstract: An apparatus and method for collecting data acquired during a seismic survey are disclosed. The apparatus is a seismic survey system, comprising a plurality of data sources, a plurality of cells, and a plurality of independent pathways. The data sources are positioned about an area to be surveyed, each data source being associated with a transmitter capable of transmitting data. The cells each contain a portion of the data sources and their associated transmitters. One of the transmitters within each cell also serves as a gateway for receiving data transmitted from the other data source transmitters within the cell. The independent pathways each contain a portion of the gateways whereby data may be transmitted along each pathway via the gateways and associated transmitters in that pathway. The method is a method for conducting a seismic survey.

Abstract: Detecting fraud involving use of an asynchronous circuit in the place of a card having an electronic circuit that is synchronous. A given excitation signal is applied to the electronic circuit of the card on power-up, a response pattern supplied by the circuit is recorded, the response pattern is compared with a reference pattern corresponding to the response expected from the electronic circuit to said excitation signal, and fraud conducted by means of an asynchronous circuit is identified in the event of the comparison being negative.

Abstract: The invention concerns a mobile telephone network (XPLMN) characterised in that it comprises: (a) a radio subsystem (XBBS) and management and routing subsystem (ENSS); (b) said radio subsystem (XBBS) comprising at least a first base station (BTS) link and a second base station (XBTS) link and a link of the base station controllers (BSC, XBSC); (c) the base stations (XBTS) of the first link, communicating directly with their associated base station controllers (BSC) with specific means; (d) the base stations (XBTS) of said second link, communicating with the associated base station controller (XBSC) via the public switched telephone network (PSTN).

Abstract: Detecting fraud involving an electronic memory card having a given operating frequency (F0) and used in a telephone set. An excitation signal (si) of variable frequency is applied to the card, and a response pattern (M) produced by the card responsive to a low frequency excitation is recorded. A determination is made that fraud is taking place when the response pattern becomes distorted at an excitation frequency that is lower than the operating frequency (F0) of the card.

Abstract: A method of recording successive balances in an electronic memory constituted by a plurality of memory locations each having an initial state "0" and a final or "written" state "1". The memory includes at least one memory region split into two memory zones, with each of the two memory zones including the same number of memory locations, and with each memory location occupying a rank in an ordered relationship defined in the memory zone to which is belongs, with two memory locations of corresponding rank constituting a pair of memory locations which is likewise distinguished from the other pairs by a rank. Before each recording event, the region includes a single reference pair CR.sub.n-1 having its two memory locations in different states, with the other pairs being constituted by memory locations which are both in the initial state C(O,O) or memory locations which are both in the final state C(1,1). In order to write a new balance S.sub.

Abstract: A method and apparatus for protecting a selective access system against fraudulent use of a magnetic card having a confidential card. Each cade (CM) is associated with a class corresponding to a zone of a memory (PROM). The number of classes is equal to the number of zones and is substantially less than the number of cards (CM) which may be presented. At each failure to input a confidential code, one of the bits is modified in the corresponding memory zone.

Abstract: The method in suitable for authenticating electronic memory cards intended for authorizing the supply of goods or services after being processed by a card reader machine. The card memory includes at least three zones (Z.sub.1, Z.sub.2, Z.sub.3) comprising a first zone (Z.sub.1) which is readable from outside and which contains information (I) and a corresponding signature (S) obtained by means of secret data (D) recorded in the third zone (A.sub.3) which cannot be read from outside the card. The second zone (Z.sub.2) which can be read from outside the card contains the result of secret key and public key encoding all of the data contained in the first zone. This method provides effective protection against several types of fraud.