Array Element Gain and Phase Estimation in the Presence of Interference

Presented is a method to estimate the element gains and phases of a sensor array when interfering signals, including specular multipath, are present. A movable calibration source is used. The element gains are derived from the relative output powers at the array elements. The element phases are obtained by transforming the array snapshots to make the source direction appear fixed and then maximizing a function constructed with the transformed snapshots. Computer simulations produce highly accurate estimates of element gains and phases when the signal directions are known and the signal-to noise ratio is reasonably high. When the directions are not known, the set of element phase estimates contains an additional component which produces a bias in direction estimates. Array calibration, Element gains, Element phases, Specular multipath interference.