PROBLEM TO BE SOLVED: To provide an ultrasound signal processing device which adaptively achieves both high spatial resolution and high temporal resolution in a synthetic aperture method using unfocused ultrasound beams, and also to provide an ultrasound diagnostic device including the ultrasound signal processing device.SOLUTION: The ultrasound signal processing device comprises: a transmission unit for causing an ultrasound probe to transmit an ultrasound beam into a subject for each transmission event while changing the traveling direction of the ultrasound beam for each transmission event； a reception processing unit for generating an acoustic line signal in synchronization with each transmission event； a synthesizing unit for generating an intermediate synthesized acoustic line signal by synthesizing acoustic line signals in the first to latest transmission events associated with synthetic acoustic line signals； an evaluation unit for calculating an evaluation value from the intermediate synthesized acoustic line signal to determine whether or not to perform the next transmission event； and an outputting unit for outputting the intermediate synthesized acoustic line signal as a synthesized acoustic line signal when the evaluating unit determines that the next transmission event is not performed.SELECTED DRAWING: Figure 3【課題】、非焦点波ビームを用いた合成開口法において、空間解像度と時間解像度とを適応的に両立させる超音波信号処理装置、および、それを用いた超音波診断装置を提供する。【解決手段】超音波ビームの進行方向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探触子に送信させる送信部と、各送信イベントに同期して音響線信号を生成する受信処理部と、合成音響線信号に係る最初の送信イベントから最新の送信イベントまでの音響線信号を合成して中間合成音響線信号を生成する合成部と、中間合成音響線信号から評価値を算出し、次の送信イベントを行うか否かを判断する評価部と、評価部が次の送信イベントを行わないと判断したとき、中間合成音響線信号を合成音響線信号として出力する出力部とを備える。【選択図】図３
