The influence of directional spreading of waves is significant for wave-induced loads, wave breaking and nonlinearity of the waves. For physical model testing performed at test facilities such as the Ocean and Coastal Engineering Laboratory at Aalborg University, it is crucial to validate if the test conditions match the target sea states by measurement and analysis of the generated directional wave field. Examples of phenomena that often occur in the laboratory, but seldom are included in the mathematical model for directional spectrum estimation are reflections and cross modes. These will contribute with additional directions in the sea state, that existing methods struggle to handle. The current study will present a new extension of an existing method applicable for waves generated from the single summation method. The new method allows for separation of oblique reflections, which is not yet covered by the existing methods.
