The sonic boom problem is a great barrier to the application of supersonic aircraft，and the accurate sonic boom prediction method is the key of the sonic boom problem. Waveform parameter method and augmented Burgers equation method are frequently used for the sonic boom prediction. Compared with the waveform parameter method，the augmented Burgers equation method has more complicated model and higher prediction accuracy. To solve the augmented Burgers equation，an effective nonlinear effect solving method is put forward. A far-field sonic boom signature prediction method based on operator splitting method is established，and verified with examples provided by Second Sonic Boom Prediction Workshop（SBPW-2）. The influence of time，space grid density and buffer signal on prediction results are analyzed. The results show that it is unnecessary for the sonic boom solving method to get the required grid density while time and space grid is converged，but to select the suitable grid density ac?cording to practical accuracy demand. The buffer signature does not seem to be necessary for small aircraft such as corporate ones，but for bigger aircraft the buffer signature is essential