Abstract: The present disclosure provides a method and a system for acquiring seismic data of a four-component ocean bottom node (OBN). The method is implemented by the system, comprising controlling installations of a plurality of ocean bottom submerged buoys and a plurality of four-component OBN seismic data acquisition instruments and sending positioning signals and timing signals to the plurality of ocean bottom submerged buoys through armored opto-electronic composite cables. The method also includes obtaining real-time and uninterrupted water temperature data, pressure data, density data, and salt saturation data along the armored opto-electronic composite cables from the ocean surface to locations of the plurality of ocean bottom submerged buoys, and calculating real-time and three-dimensional data of waters of a whole measurement work area through interpolation.

Abstract: The present disclosure provides a device for full-wave field seismic source based on a gas explosion technology and a method for acquiring seismic data. The device includes a cylindrical explosion-proof metal outer barrel, and four sides of the explosion-proof metal outer barrel are fixedly connected to four high-strength steel plates. The device also includes a cylindrical explosion-proof metal gas explosion inner barrel and pipelines for injecting high-pressure air and high-pressure gas into the gas explosion inner barrel. A center of the gas explosion inner barrel is installed with an electronic ignition gun, which is connected to a GPS timing module connected to the electronic ignition gun. The device further includes a controller configured to control a seismic source of a gas explosion full-wave field.

Abstract: The present invention relates to an apparatus for accurately detecting a mains phase. The apparatus is constructed with a zero-crossing detector, a digital phase detector, a digital loop filter, and a digital controlled oscillator (DCO) of a direct digital synthesized (DDS) manner. The present apparatus employs an all-digital loop architecture and a high sampling clock to recover a signal with a phase orthogonal with the mains signal and a frequency the same as the mains signal. And jitters in the recovered signal are less than 10 us. The present apparatus is capable of implementing signal tracking of a zero frequency error and a zero phase in a wide range, and can provide a detection result of excellent performance for the power line carrier communication, mains frequency detection, etc.

Abstract: The present invention relates to an apparatus for accurately detecting a mains phase. The apparatus is constructed with a zero-crossing detector, a digital phase detector, a digital loop filter, and a digital controlled oscillator (DCO) of a direct digital synthesized (DDS) manner. The present apparatus employs an all-digital loop architecture and a high sampling clock to recover a signal with a phase orthogonal with the mains signal and a frequency the same as the mains signal. And jitters in the recovered signal are less than 10 us. The present apparatus is capable of implementing signal tracking of a zero frequency error and a zero phase in a wide range, and can provide a detection result of excellent performance for the power line carrier communication, mains frequency detection, etc.