Nonlinear Kalman filtering for self-calibration of airborne arrays

The calibration of a millimeter-wave antenna array mounted on an aircraft wing is considered. The theory and implementation of nonlinear Kalman filters, which are optimal for the desired minimum mean squared error (MMSE) criterion, are considered. Numerical results are provided for a field experiment employing a 32-element Ku-band antenna array. The implementation of the algorithms is sub-optimal due to limitations in available computational power, which reduces the model order and the accuracy of the required calculations, but the technique is effective in calibrating the array.