PROBLEM TO BE SOLVED: To provide an ultrasonic signal processing device capable of reducing an arithmetic amount of phasing addition while suppressing deterioration of spatial resolution and an S/N ratio in a synthetic aperture method using focusing type transmission beamforming, and an ultrasonic diagnosis device using the ultrasonic signal processing device.SOLUTION: An ultrasonic signal processing device includes: a transmission part for transmitting an ultrasonic beam to an ultrasonic wave main irradiation region defined by two straight lines connecting a focus point and both ends of a transmission vibrator string； a reception part for generating a reception signal string； a phasing addition part for, of the ultrasonic wave main irradiation region, setting the whole region of a region shallower than the focus point as a first object region, and a region excluding a part from a region deeper than the focus point as a second object region respectively, and generating a sub-frame acoustic line signal by subjecting the reception signal string on the basis of a reflection ultrasonic wave to phasing addition for a plurality of observation points present in the first object region and the second object region； and a synthesis part for synthesizing a frame acoustic line signal based on a plurality of the sub-frame acoustic line signals generated by the phasing addition part.SELECTED DRAWING: Figure 5【課題】集束型の送信ビームフォーミングを用いた合成開口法において、空間分解能及びＳ／Ｎ比の低下を抑制しながら整相加算の演算量を削減することのできる超音波信号処理装置、及び、それを用いた超音波診断装置を提供する。【解決手段】フォーカス点と、送信振動子列の両端とを結ぶ２つの直線によって規定される超音波主照射領域に超音波ビームを送信させる送信部と、受信信号列を生成する受信部と、超音波主照射領域のうち、フォーカス点より浅い領域の全域を第１対象領域として、フォーカス点より深い領域より一部を除外した領域を第２対象領域として、それぞれ設定し、第１対象領域内と第２対象領域内とに存在する複数の観測点について、反射超音波に基づく前記受信信号列を整相加算してサブフレーム音響線信号を生成する整相加算部と、整相加算部が生成した複数のサブフレーム音響線信号に基づき、フレーム音響線信号を合成する合成部とを備える。【選択図】図５
