Fig. 2 Comparison of localization results for the SwellEx96 towed sources with MFP I, MFP II and TMFP. (a) Range estimation error and (b) depth estimation error for the shallow source; (c) Range estimation error and (d) depth estimation error for the deep source.
To illustrate the advantages of TMFP compared with MFP I and MFP II, we give the variation in range and depth estimation ambiguity surface versus processing time of TMFP, MFP I and MFP II, respectively. The data processing procedure is as follows:
(1) For segment data , the ambiguity surfaces , and can be obtained by applying TMFP, MFP I and MFP II.
(2) The peak position of the ambiguity surfaces is found. The depth dimension ambiguity function and range dimension ambiguity function corresponding to the peak position are extracted. and are for TMFP, and are for MFP I, and are for MFP II.
(3) Based on the results of 19 times of processing, the ambiguity surfaces in depth and range for MFP I, MFP II and TMFP are shown in Figs. 3 and 4, Fig. 3 shows the ambiguity surface for shallow source with a depth of 9 m, Fig. 4 shows the ambiguity surface for deep source with a depth of 54 m.