Effect of random antenna-position errors on a least-squares direct data domain approach for space-time adaptive processing

The equivalent isotropically radiated power (EIRP) degradation due to random position errors for space-time adaptive processing (STAP) is presented, based on the relationship between the EIRP degradation and the standard deviation or the uniform bound of the probability distribution of location of the antenna elements. We simulate a direct data domain least-squares (D ³ LS) approach for STAP. In this simulation, two situations are considered. In the first case, the antenna elements at every time instance are assumed to have different spatial positions from the previous time instance. For the other case, the antennas are assumed to be randomly located, but are assumed to be fixed in a coherent processing interval (CPI). It is demonstrated that whether the locations of the antenna are fixed or vary within a CPI with identical random errors, the output signal-to-interference and noise ratio (SINR) are almost the same. When the antenna elements are moved randomly, the output SINR is less than the unperturbed case. We can develop a bound on the EIRP degradation due to the D ³LS approach to STAP based on the random position errors.