摘要:
A high resolution bathymetric sidescan sonar system for measuring micro-geomorphy of the sea bottom having an underwater vehicle, an underwater electronic subsystem mounted on the underwater vehicle and containing a transmitter and a receiver, and two sonar arrays mounted symmetrically on two sides of a lower part of the underwater vehicle and being connected to the underwater electronic subsystem through a cable. Each sonar array has a transmitting linear array and three or more parallel receiving linear arrays. The parallel receiving linear arrays are arranged at equal spaces, and the space d between two adjacent parallel receiving linear arrays is λ>d≧λ/2, in which λ is a wavelength of an acoustic wave, and an operation frequency of the parallel receiving linear arrays ranges from 30 kHz to 1200 kHz.
摘要:
A high resolution bathymetric sidescan sonar system for measuring micro-geomorphy of the sea bottom having an underwater vehicle, an underwater electronic subsystem mounted on the underwater vehicle and containing a transmitter and a receiver, and two sonar arrays mounted symmetrically on two sides of a lower part of the underwater vehicle and being connected to the underwater electronic subsystem through a cable. Each sonar array has a transmitting linear array and three or more parallel receiving linear arrays. The parallel receiving linear arrays are arranged at equal spaces, and the space d between two adjacent parallel receiving linear arrays is λ>d≧λ/2, in which λ is a wavelength of an acoustic wave, and an operation frequency of the parallel receiving linear arrays ranges from 30 kHz to 1200 kHz.
摘要:
The present invention provides a method of source number estimation based on eigenspace in DOA estimation, including: (1) obtaining signals received by uniform linear array; (2) calculating a covariance matrix according to the received signals; (3) calculating a complex-valued covariance matrix or a covariance matrix after real-valued computations; (4) conducting eigendecomposition to the covariance matrix to obtain its eigenvector matrix; (5) calculating a source number decision based on the eigenvector; (6) calculating a ratio; and (7) source number estimation. The present invention can accurately estimate source number and save huge amounts of computation during signal processing in DOA estimation, and lower the cost of hardware.
摘要:
The present invention provides a method of source number estimation based on eigenspace in DOA estimation, including: (1) obtaining signals received by uniform linear array; (2) calculating a covariance matrix according to the received signals; (3) calculating a complex-valued covariance matrix or a covariance matrix after real-valued computations; (4) conducting eigendecomposition to the covariance matrix to obtain its eigenvector matrix; (5) calculating a source number decision based on the eigenvector; (6) calculating a ratio; and (7) source number estimation. The present invention can accurately estimate source number and save huge amounts of computation during signal processing in DOA estimation, and lower the cost of hardware.
摘要:
A processing method of this invention relates to an angle of arrival estimation technique, where by a high resolution bathymetric sidescan sonar signal process method it measure the micro-geomorphy of the sea bottom. This is the multi-subarray sub-space fitting method. The invention shows that when the array elements number is fixed, no matter there is mutual coupling or not between array elements, there exists one sub-array which has the smallest phase estimation standard deviation, the method of this invention overcomes the phase error caused by mutual coupling and enhances the measurement precision.
摘要:
A processing method of this invention relates to an angle of arrival estimation technique, where by a high resolution bathymetric sidescan sonar signal process method it measure the micro-geomorphy of the sea bottom. That is the multi-subarray sub-space fitting method. The invention shows that when the array elements number is fixed, no matter there is mutual coupling or not between array elements, there exists one subarray which has the smallest phase estimation standard deviation, the method of this invention overcomes the phase error caused by mutual coupling and enhances the measurement precision.
摘要:
The current invention provides compositions, which are useful as stationary phases for a variety of chromatographic applications, such as high performance liquid chromatography (HPLC) and solid-phase extraction (SPE). The compositions provide both strong aromatic and hydrophobic interactions with components of a sample. Moreover, the invention provides compositions of new silanes, their immobilization on a solid substrate, such as silica, to form new stationary phases.
摘要:
A method for assisting a transmission oil pump in a hybrid electric powertrain to generate transmission oil pressure rapidly during vehicle start. An electric motor is initially utilized to provide momentary torque to rotate an oil pump and rapidly generate transmission oil pressure. After initial assistance is provided by the electric motor, an oil pump electric motor powers the oil pump and maintains oil pressure within the hybrid powertrain.
摘要:
The invention provides compounds and pharmaceutical compositions thereof, which are useful as protein kinase inhibitors, as well as methods for using such compounds to treat, ameliorate or prevent a condition associated with abnormal or deregulated kinase activity. In some embodiments, the invention provides methods for using such compounds to treat, ameliorate or prevent diseases or disorders that involve abnormal activation of c-kit or c-kit and PDGFR (PDGFRα, PDGFRβ) kinases.
摘要:
A method for assisting a transmission oil pump in a hybrid electric powertrain to generate transmission oil pressure rapidly during vehicle start. An electric motor is initially utilized to provide momentary torque to rotate an oil pump and rapidly generate transmission oil pressure. After initial assistance is provided by the electric motor, an oil pump electric motor powers the oil pump and maintains oil pressure within the hybrid powertrain.