Direction of arrival (DOA) plays an essential role in wireless communications, which has been widely utilized in localization and intelligent navigation. Recently, with explosive growth of wireless communication devices, the electromagnetic environment has become more and more complicated. In such electromagnetic environment, it remains a challenge to achieve robust DOA estimation while maximizing source discrimination with limited physical sensors. Additionally, conventional DOA methods are usually based on Gaussian noise assumption, while these methods would suffer from performance degradation in impulsive noise. Aiming at addressing these issues, we propose a novel robust DOA estimation method with high degree of freedom (DOF). In the proposed method, firstly, a novel mirror coprime array (MCA) structure is proposed for DOA estimation. Relying on the properties of non-circular signals, MCA can make full use of the received signals from limited physical elements to accurately estimate more DOAs with high DOF. Next, a novel square-based correntropy operator (SCO) is defined to effectively suppress impulsive noise in complicated electromagnetic environment. Also, we demonstrate the effectiveness of SCO in impulsive noise suppression theoretically. Further, accurate and robust DOA estimation with high DOF can be realized through the proposed MCA-SCO-MUSIC method, which innovatively fuses the pseudo-covariance matrix generated by SCO into MCA based DOA estimation method. Finally, we conduct a series experiments to evaluate the performance of proposed method, and simulation results demonstrate its effectiveness in enhancing DOF without adding physical array elements. Moreover, the proposed method exhibits better performance compared to contrastive methods in impulsive noise.