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This manual presents the computer program package for the generalized ILSGLD scattering model. The text includes a complete description of the program itself as well as a brief description of the ILS system and antenna patterns. The program listings are included as appendixes, and contain both input- generation programs and output-plotting programs. For a technical mathematical analysis of the system see the FAA report, 'ILS Glide Slope Performance Prediction: Multipath Scattering'. The present report is a partial revision of part II of report FAA-RD-74-157B. The revisions include the treatment of scattering from randomly oriented rectangular surfaces., See also ADA009432.

A mathematical model has been developed which predicts the performance of ILS glide slope systems subject to multipath scattering and the effects of irregular terrain contours. The model is discussed in detail and then applied to a test case for purposes of illustration. A complete listing of all computer programs has been appended to the report. A user's manual has been prepared under separate cover.

This manual presents the complete ILSS (revised ILSLOC) computer program package. In addition to including a thorough description of the program itself and a listing with comments, the manual contains a brief description of the ILS system and antenna patterns. To illustrate the program, a test case has been created and the figures of the case are incorporated in the report. Program DYNM and program ILSPLT are included as appendixes. The ILSPLT, Complete with sample graphs, is a plotting routine for ILSLOC. For a technical mathematical analysis of the system, see report FAA-RD-72-137 (AD754517), 'Instrument Landing System Scattering.' This report revises in part an earlier report FAA-RD-73-76, 'Users Manual for ILSLOC: Simulation for Derogation Effects on the Localizer Portion of the Instrument Landing System'. The revisions include the treatment of triangular scatterers and glide slope antenna systems. (Author)

The manual presents the complete ILSLOC computer program package. In addition to including a thorough description of the program itself and a commented listing, the manual contains a brief description of the ILS system and antenna patterns. To illustrate the program a test case was created and the figures of the case are incorporated in the report. Program DYNM and program ILSPLT are included as Appendices. The ILSPLT, complete with sample graphs, is a plotting routine for ILSLOC. For a technical mathematical analysis of the system, the FAA report 'Instrument Landing System Scattering' No. FAA-RD-72-137 should be consulted.

A mathematical model for predicting the performance of ILS glide slope arrays in the presence of certain types of terrain irregularites has been developed. The model is discussed in detail and then applied to a number of typical glide slope siting problems for purposes of illustration. A User's Manual for exercising the model forms Part 2 of this report.

The additional derogation to the localizer front and back courses caused by a water tower placed near the localizer site is predicted. This prediction is made with the Transportation Systems Center (TSC) localizer model. This additional derogation to the front and back courses is expected to amount to two or three microamperes. (Author)

The TSC electromagnetic scattering model has been used to predict the course deviation indications (CDI) at the planned Dallas Fort Worth Regional Airport. The results show that the CDI due to scattering from the modeled airport structures are within Category I requirements on all four modeled runways when the capture effect localizer (Alford 1B) is used but only marginally acceptable when the standard V-Ring localizer is used. Category II requirements for the designated Category II runway are met only by the capture effect antenna. The report also presents the results of the TSC validation test in which Syracuse Hancock Airport was modeled. Theoretical and flight recorded data were compared and good agreement was obtained. (Author)

The TSC electromagnetic scattering model is used to dtermine the expected ILS localizer performance for the planned 28R runway at San Francisco airport. It is found that the V-Ring and the 14/6 Alford array as well as the larger 22/8 Alford array operating with a 10db "capture effect ratio, " do not produce an acceptable course meeting FAA Categor I tolerances. The feasibility and advantages of operating the Alford array at higher capture effect ratios is discussed. Based on a "worst case" airport enviroment, the maximum capture ratio obtainable with the Alford 22/8 array is calculated and shown to lead to a marginally acceptable Category I course structure. For an "ideal" airport environment it is possible to use high capture ratios with the result that Category I requirements are easily satisfied and Category II tolerances marginally so with the Alford 22/8 array. The course structure in each case has been calculated under the assumption that the derogator is a metallic perfect reflector.

The TSC ILS localizer model is used to predict the performance of the Texas Instruments "wide aperture" parabolic antenna as a localizer system for runway 28R at San Francisco Airport. Course derogation caused by the new American Airlines hangar is calculated under the assumption that this structure is a metallic perfect reflector. It is found the TI System operated with a "capture effect ratio" of 10dB does not meet Category I requirements. If it is possible to operate the system within equipment limitations at a 16dB capture effect ratio, performance should be adequate for Category I, but it is still inadequate for Category II. This performance is inferior to that predicted for the Alford 22/8 array for the same situation in an earlier study.

Defintion of instrument landing system, Antenna patterns, ILS simulation description, Test case for the ILSLOC computer program, Appendices, The manual presents the complete ILSLOC computer program package. In addition to including a thorough description of the program itself and a commented listing, the manual contains a brief description of the ILS system and antenna patterns. To illustrate the program a test case was created and the figures of the case are incorporated in the report. Program DYNM and program ILSPLT are included as Appendices. The ILSPLT, complete with sample graphs, is a plotting routine for ILSLOC. For a technical mathematical analysis of the system, the FAA report 'Instrument Landing System Scattering' No. FAA-RD-72-137 should be consulted.

The Transportation Systems Center (TSC) ILS Localizer Performance Prediction Model was used to predict the derogation to an Alford 1B Localizer caused by vehicular traffic traveling on a roadway to be located in front of the localizer. Several different types of car distributions were modeled and found to produce negligible additional derogation to the Alford B Localizer performance operating for Runway 10 at the New Orleans airport. However, because of the nature of the scattering causing the derogation and the capabilities of the TSC model (See text), it is suggested that additional validation of the TSC results be obtained.

The TSC electromagnetic scattering model has been used to predict the course deviation indications (CDI) at the planned Dallas Fort Worth Regional Airport. The results show that the CDI due to scattering from the modeled airport structures are within Category I requirements on all four modeled runways when the capture effect localizer (Alford 1B) is used but only marginally acceptable when the standard V-Ring localizer is used. Category II requirements for the designated Category II runway are met only by the capture effect antenna. The report also presents the results of the TSC validation test in which Syracuse Hancock Airport was modeled. Theoretical and flight recorded data were compared and good agreement was obtained. (Author)

Inroduction, Description, Results, Conclusion, The additional derogation to the localizer front and back courses caused by a water tower placed near the localizer site is predicted. This prediction is made with the Transportation Systems Center (TSC) localizer model. This additional derogation to the front and back courses is expected to amount to two or three microamperes.

The manual presents the complete ILSLOC computer program package. In addition to including a thorough description of the program itself and a commented listing, the manual contains a brief description of the ILS system and antenna patterns. To illustrate the program a test case was created and the figures of the case are incorporated in the report. Program DYNM and program ILSPLT are included as Appendices. The ILSPLT, complete with sample graphs, is a plotting routine for ILSLOC. For a technical mathematical analysis of the system, the FAA report 'Instrument Landing System Scattering' No. FAA-RD-72-137 should be consulted. (Author)

Introduction, Basic theory, Numerical results, A mathematical model has been developed which predicts the performance of ILS glide slope systems subject to multipath scattering and the effects of irregular terrain contours. The model is discussed in detail and then applied to a test case for purposes of illustration. A complete listing of all computer programs has been appended to the report. A user's manual has been prepared under separate cover.