This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new approach and landing guidance system. This second volume of the report presents the mathematical models and validation data for the MLS techniques which were assessed in detail by the All Weather Operations Panel of the Interational Civil Aviation Organization. The specific techniques modeled are: 1. The Time Reference Scanning Beam (TRSB) system proposed by the United States (US) and Australia, with prime emphasis on the US equipment implementation and field test data, 2. the Doppler scan (DMLS) proposed by the United Kingdom, and 3. the DME Based Landing System (DLS) proposed by the Federal Republic of Germany.