It is an eternal topic to study the minimum loss under the maximum transmission distance and the practicality of radio propagation in the navigation of ships. The transmission loss by dividing it to Median medium attenuation and Media attenuation correction factor is discussed. The Longley-Rice Model is introduced and improved; the correlation proportion of our model is work out. Then the reflection correction factor is calculated in the case of silent and turbulent ocean, which comes to the total loss and strength of the first reflection. The signal to noise ratio is explained and the relationship between various angle of incidence and correction factor are explored. According to fixed signal to noise ratio 14, the highest bounce frequency is got.