Study On The Error Estimation And Remedy Of The Distributed Small Satellites

A new spaceborne radar system was proposed in the middle of the ninety's, which is the constellation composed by several small satellites (it was also called as distributed small satellite radar array). In this paper, the author studied the calibration and remedy method of the distributed small satellite system errors aiming at the inevitable baseline error and gain and phase error of the distributed small satellite radar array. On the basis of a simply introduction of the several available calibrations of array errors, a new baseline error and gain and phase error calibration method is proposed based on the reflector on the ground. This method can obtain the estimation of the steering vector directly and is adaptive to both far field and near field models. Then the author studied the satellite array distributing in three-dimensional space and proposed a new method that can calibrate and remedy the baseline error and gain and phase error based on a strong reflector on the ground. This method need not iterative operation and can avoid the local optimum problem caused by search. It need only do once Fourier Transform on the azimuth of the echoes and can obtain a high estimation precision so the amount of the computation is decreased greatly. At last, a new imaging algorithm without ambiguity is proposed in this paper combined with the nulling adjustment method of the array pattern. This method has a relative small amount of calculation and its performance loss is very little so it is expected to be used in application.