| Ship's motion was changed in Multi-beam Swath Bathymeter survey process by wave and wind. Resolution of Multi-beam Swath Bathymeter was affected, the transmit beam will not reach the position of expectation sea bottom and cause survey error. Old day's Multi-beam Swath Bathymeter can't solve this problem completely. This thesis will study on compensate fully for ship's pitch and yaw motion. A new compensate method use a two-dimensional projector array to concentrate the transmit beam in the athwart ship direction as well as the along track direction. By continuously sweeping this concentrated beam in the athwart ship direction while adjusting for ship's motion, complete compensation for pitch and yaw is achieved. As the ship advances, the sea floor is scanned in a series of parallel lines, analogous to a progressive scan CRT.First Multi-beam Swath Bathymeter Movement compensation model were set up in this thesis. Real-time Movement compensation software was developed. It ensure the beam's indication parameters respect to the projector array are calculated dynamically each ping to compensate for ship's motion. At last design of transmitter hardware and software based on VXI bus technique was done with DSP and DDS chips to realization signal transimt and synchronization.The swept beam technique uses a single sonar frequency to ensonify the entire swath. It is compatible with existing receiver hardware and echo signal processing software. This reduces the development required to implement the new transmitter in a bathymetric system. It also offers advantages in the shallow regions of operation relative to multiple frequency "sector scanned" operation, in that it can be applied at the shortest pulse widths consistent with frequency and array size. This allows not only full pitch and yaw compensation over the entire range of operation, but also opens the possibility for near field focusing, allowing the system to maintain its maximum resolution to its shallowest operating depth.
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