A novel extension of the cubic phase function (CPF), known as the parameterised centroid frequency‐chirp rate distribution (PCFCRD), is proposed for multicomponent linear frequency modulated signals analysis. The PCFCRD is coherent and introduces a constant delay to reduce the noise correlation. Mathematic analysis and numerical simulations demonstrate that, compared with the coherent integrated CPF, the PCFCRD can obtain a higher anti‐noise performance.