A new class of broadband arrays with frequency invariant beam pattern is proposed. By
suitable substitutions, the beam pattern of a continuous sensor array can be regarded as the
Fourier transform of its spatial and temporal parameters. For the design of practical discrete
sensor arrays, it can be regarded as an approximation to the continuous sensor case and a
simple design method is provided, which can be applied to linear, rectangular and cubic
broadband arrays.

A simple method for the design of a class of arrays with frequency invariant beam patterns is
proposed. Starting from the desired frequency invariant beam pattern of an nD array, the
proposed method uses a series of substitutions and an nD inverse Fourier transform to
obtain the desired frequency responses of the filters following each sensor. Given their
desired frequency responses, these filters can be realized by either an analogue filter or a
digital filter. Hence the proposed method can cover the design of broadband arrays with …