Self-adaptive fast arc tangent system and method and ultrasonic imaging device

The invention discloses a self-adaptive fast arc tangent system, which comprises: a construction module used for constructing a lookup table between fitting orders and fitting precision based on an arc tangent function; a selection module used for selecting a fitting order meeting a preset fitting precision requirement according to the constructed lookup table; and a fitting module used for constructing a fitting model based on the selected fitting order and performing fitting estimation on the arc tangent function according to the constructed fitting model. According to the method, the fitting model can be adaptively adjusted according to the actual precision requirement to obtain an expected result; and the lookup table of the fitting order and the fitting precision can be established in advance, and in addition, the fitting model only needs multiplication and addition operation, so that the calculation complexity of the method is relatively low. 本发明公开了一种自适应的快速反正切系统，包括：构建模块，用于构建基于反正切函数的拟合阶数和拟合精度之间的查找表；选择模块，