Based on the per unit area second-order cross section spectrum of the ocean proposed by Howell

a new algorithm to extract ocean wave information from HF radar backscatter by a narrow-beam antenna system is presented

in which the integral object is changed and the integral range is divided asymmetrically.Numerical simulation is performed under condition of different SNR and sea state.The simulation result shows that this algorithm has preferable precision under SNR higher than 35dB.As a further test of this algorithm

comparison are made between wave height estimates obtained from wave instrument and a HF ground wave radar at 7.7MHz

using data collected during "The HF ground radar field contrast test".The average absolute error of the significant wave height is 0.32m

which demonstrates the basic accuracy and feasibility of the inversion algorithm.