To estimate an arrival direction when the arrival direction can take all directions in a horizontal space by providing an antenna element arrangement that is suited for estimating the arrival direction of a radio wave in a horizontal surface and estimating the arrival direction of the radio wave by a nerve circuit network method.

A device has a means 20 for obtaining a vector with the values of real and imaginary parts of the ratio of complex amplitudes as elements from a signal that a radio wave signal reception element 10 being arranged at a specific position receives and a signal that a plurality of radio wave signal reception elements 11-1N being arranged on a specific trace surrounding the arrangement position of the signal reception element 10 receive, a nerve circuit network 30 that obtains the probability of the arrival direction of a radio wave signal as a value for each direction with the obtained vector as input, and an estimation means 40 for estimating the arrival direction of the above signal.