Low-complexity minimum variance ultrasonic imaging method based on power multiplication method

The invention relates to a low-complexity minimum variance ultrasonic imaging method based on a power multiplication method and belongs to the ultrasonic imaging technology field. The method comprisesthe following steps of firstly, converting an ultrasonic echo signal from an array element domain into a beam domain by using a discrete cosine change, extracting a part of beam domain data, and reducing a sample covariance matrix dimension; and secondly, solving a maximum characteristic value and a corresponding characteristic vector of the sample covariance matrix by using the power multiplication method, ignoring a part of low-energy echo signal data, simplifying inversion of the covariance matrix, and constructing a new optimal weighted vector so as to achieve a purpose of reducing algorithm complexity. An algorithm imaging effect in the invention is superior to that of a traditional delay superposition algorithm (DAS); operation efficiency of a minimum variance algorithm (MV) is farhigher than that of the mi