To provide an estimation device or the like capable of accurately estimating a direction or the like in which a dynamic body exists by using a wireless signal in a short period of time.SOLUTION: An estimation device comprises: a receiving unit 13 to observe received signals, for a first period, which are transmitted from one transmission antenna element and respectively received by a plurality of receiving antenna elements and include reflection signals reflected from a dynamic body； a complex transfer function calculation unit 14 to calculate complex transfer functions, respectively indicating a transfer characteristic between the one transmission antenna element and the plurality of receiving antenna elements, from each of a plurality of received signals observed in the first period； a difference information calculation unit 15 to calculate two or more pieces of difference information which indicates difference between two complex transfer functions, among the plurality of calculated complex transfer functions, at two time points in a predetermined interval and is expressed by a N-dimensional vector； and a direction estimation process unit 16 to estimate a direction in which the dynamic body exists, with the estimation device 10 as a directional reference, by using the calculated two or more pieces of difference information.SELECTED DRAWING: Figure 1【課題】無線信号を利用して動体が存在する方向等の推定を、短時間かつ高精度に行うことができる推定装置等を提供すること。【解決手段】複数の受信アンテナ素子のそれぞれにより受信された受信信号であって、１個の送信アンテナ素子から送信され、動体によって反射された反射信号を含む受信信号を、第１期間、観測する受信部１３と、第１期間に観測された複数の受信信号それぞれから、１個の送信アンテナ素子と複数の受信アンテナ素子のそれぞれとの間の伝搬特性を表す複素伝達関数を算出する複素伝達関数算出部１４と、算出された複数の複素伝達関数のうち所定間隔の２つの時点における２つの複素伝達関数の差分を示す差分情報であってN次元のベクトルにより表現される差分情報を２以上算出する差分情報算出部１５と、当該２以上算出された差分情報を用いて、推定装置１０を方向の基準として動体の存在する方向を推定する方向推定処理部１６と、を備える。【選択図】図１
