Polynomial fitting based on least squares approximates for first-order Tracy-Widom distribution

Tracy-Widom distribution can primely describe the limit of largest eigenvalue noise matrix, so it is widely used in field signal processing and wireless communication. The exact expression this very complex difficult to be applied practice. Therefore, an approximate method based on least squares proposed, which optimal fitting order coefficient are determined by minimizing average uncertainty. simulation results show that accurately predict proves effectiveness polynomial first-order distribution.