Direction Finding Using Coprime Array with Sensor Gain and Phase Errors

This paper investigates the issue of direction finding of multiple signals using coprime array with sensor gain and phase errors. As the sensor errors decrease the performance of direction estimation, it proposes a calibration method with one signal, where one accurate direction signal enables to obtain high precise result. By building the rough direction signal in real system as usual, it introduces the gain self-calibration and iterative self-calibration to enhance the performance of error estimation, which is based on the rough error estimate by one signal calibration. Considering the analysis of computational complexity and performance simulation, the gain self-calibration improves the performance in low signal to noise ratio compared with no self-calibration and the iterative self-calibration gets the best performance with the most computational complexity. With known error values, it can be found more signals than the sensor number with coprime array.