Mixed autoregressive-moving average modeling of the response of a linear array antenna to incident plane waves

It is shown that when a linear array of antenna elements is excited by a set of plane waves, the resulting response of the array may be modeled as a special form of mixed autoregressive-moving average (ARMA) process in which the autoregressive and moving average parts have the same parameters. This model provides the basis for applying the Pisarenko spectral decomposition to estimate the angles of arrival of the plane waves at the array.