PROBLEM TO BE SOLVED: To provide an ultrasonic signal processing apparatus capable of reducing a computation amount of phasing addition while suppressing deterioration of spatial resolution and an S/N ratio in a synthetic aperture method using focusing type transmission beam forming.SOLUTION: An ultrasonic signal processing apparatus includes: a transmission part for causing an ultrasonic probe to transmit an ultrasonic beam to the inside of a subject for each transmission event while changing a focus point for defining a position where the ultrasonic beam is focused for each transmission event； and a phasing addition part for generating an acoustic line signal by specifying a vibrator existing on a straight line passing through an observation point and the focus point for each observation point in an object region, executing processing to identify a reception signal string for the vibrator as an observation point signal for each transmission event, and subjecting the observation point signal identified in each transmission event to weighted phasing addition among a plurality of transmission events.SELECTED DRAWING: Figure 4【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を提供する【解決手段】超音波ビームが集束する位置を規定するフォーカス点を送信イベントごとに変更しながら、被検体内に超音波ビームを送信イベントごとに前記超音波プローブに送信させる送信部と、対象領域内のそれぞれの観測点について、前記観測点と前記フォーカス点とを通る直線上に存在する振動子を特定して前記振動子に対する前記受信信号列を観測点信号として同定する処理を前記送信イベントごとに行い、それぞれの送信イベントで同定された観測点信号を複数の送信イベント間で重み付き整相加算することで音響線信号を生成する整相加算部とを備える。【選択図】図４
