Envisat ASAR WSS data processing

hello, it’s first time for me to process the ASAR WAA data. As we know,every WSS product contains 5 subswaths, I want to mosaic them into a image and do localIncidenceAngle normalization .So I used the function "WSS Deburst,Calibrate and Detect " split the product into 5 subswaths and mosaic them,but the mosaiced image can’t be terrain corrected and acquire the localincidenceangle band.What steps should I do to achieve my purpose?

Did you able to do Terrain correction? I am also facing the same issue?