Nearfield effects in end‐fire line arrays

An “exact” closed‐form solution for the acoustic field from a continuous end‐fire line array is presented. Interactions between the array elements are ignored, but no approximations are made regarding the position of the field point. (This model lends itself particularly well to the study of the response of parametric receivers.) The results are presented in the form of beam patterns as a function of range. It is shown that the range where the transition between the nearfield and the farfield is obtained depends only on the length of the array and that the beam patterns within the nearfield can be substantially more narrow than the farfield beam patterns.