f Source signature estimation using plane wave decomposition

Recently a new deterministic technique for source signature estimation in one-dimensional models of media was introduced (Shtivelman and Loewenthal, 1988; Loewenthal and Shtivelman, 1989). The technique was developed for a general case of multilayered models with arbitrary locations of the source and two closely spaced receivers (provided the source is above the receivers) and can he applied to both marine and land data. The technique is based on the application of two sequential extrapolation processes and does not require explicit separation of the wave field into up and downgoing components. Lately, the method has been extended to the two-dirnensional problem (Loewenthal and Shtivelman, 1990).