Unknown mutual coupling effect can degrade the performance of a direction of arrival estimation method. In this letter, a new method is proposed for uniform linear arrays (ULAs) to tackle this problem. Considering the sparse representation exploiting the inherent structure of the received data, the effective block sparse representation and the convex optimization problem are constructed using the steering vector parameterizing method. The proposed solution based on the ${l} _{1}$ - singular value decomposition can exploit the information provided by the whole array and the Toeplitz structure of the mutual coupling matrix in the ULA. Simulation results are provided to demonstrate its performance with unknown mutual coupling in comparison with some existing methods.