SENG 6837

Wide Area Augmentation System Navigation Infrastructure Environment Simulator

(WAAS-NIES) Project

System Requirements Document

Version 1.2

SRD Document HistoryDate Version Description Author

February 15, 2006 1.0 Initial draft issue Clay R. Bailey

March 2, 2006 1.1 Draft Updates Clay R. Bailey

March 17, 2006 1.2 Updates Kalyn L.Bullock

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Table of Contents

1. INTRODUCTION.............................................................................................................................. 5

1.1 Purpose...............................................................................................................................................................5

1.2 Scope...................................................................................................................................................................5

1.3 Definitions, Acronyms and Abbreviations......................................................................................................5

1.4 Reference and Applicable Documents............................................................................................................5

1.5 Document Overview..........................................................................................................................................5

2. SYSTEM OVERVIEW....................................................................................................................... 6

2.1 WAAS-NIES System Architecture..................................................................................................................6

2.2 Assumptions and Constraints..........................................................................................................................6

2.3 User Characteristics..........................................................................................................................................6

2.4 Assumptions and Dependencies.......................................................................................................................6

3. REQUIREMENTS............................................................................................................................. 7

3.1 User Requirements............................................................................................................................................7

3.2 System Requirements.......................................................................................................................................7

3.3 Interface Requirements..................................................................................................................................10

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Table of FiguresFigure 2.1-1……………………………………………………………………WAAS-NIES Hardware Architecture

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System Requirements Document1. Introduction

The Systems Requirements Document (SRD) establishes the system level requirements for the Wide Area Augmentation System Infrastructure Environment Simulator (subsequently referred to as WAAS-NIES). These requirements have been derived from several sources, including the client: Corbin Holtz from the Lockheed Martin Corporation. The major functional elements of the WAAS-NIES require developmental integration of innovated graphics and computer technology. The System Definition Document must be in compliance with and satisfy the requirements in this SRD.

1.1 Purpose

This SRD specifies the engineering and qualification requirements for the WAAS-NIES. The contents of this document will serve as the basis for the design and testing of the WAAS-NIES. Upon approval, this document will become part of the WAAS-NIES technical baseline.

1.2 ScopeThis Systems Requirements Document (SRD) applies to the WAAS-NIES.

1.3 Definitions, Acronyms and Abbreviations

COTS Commercial off-the-shelfGEO Geostationary SatellitesGPS Global Positioning SystemGUI Graphical User InterfaceGUS Geostationary Uplink SiteICD Interface Control DocumentSEM System Engineering ManagementSEMP System Engineering Management PlanTBD To Be DeterminedTBS To Be suppliedUHCL University of Houston Clear LakeWAAS Wide Area Augmentation System

WAAS-NIES Wide Area Augmentation System Infrastructure Environment Simulator

WMS Wide Area Master StationWRE Wide Area Reference StationWRS Wide Area Reference Station

1.4 Reference and Applicable Documents

W-1 WAAS-NIES Statement of WorkW-2 Risk Management PlanW-3 System Design DefinitionW-4 Concept of Operations

1.5 Document OverviewThe following provides a summary of each section contained within this System Requirements Document:

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Section 1introduces the WAAS-NIES and describes the purpose of this document.Section 2 gives an overview of the WAAS-NIES system.Section 3 identifies the requirements of the WAAS-NIES system.

2. System Overview

The Wide Area Augmentation System (WAAS) is a GPS-based navigation and landing system that provides precision guidance to aircrafts at thousands of airports and airstrips, where there is currently no precision landing capability. WRSs and integrity monitors are widely dispersed data collection sites that contain GPS/WAAS ranging receivers that monitor all signals from the GPS, as well as the WAAS geostationary satellites. The reference stations collect measurements from the GPS and WAAS satellites so that differential corrections, ionospheric delay information, GPS/WAAS accuracy, WAAS network time, GPS time, and UTC can be determined. The WRS and integrity monitor data are forwarded to the central data processing sites. These sites process the data in order to determine differential corrections, ionospheric delay information, and GPS/WAAS accuracy, as well as verify residual error bounds for each monitored satellite. The WAAS-NIES provides a simulation of the accuracy of the WAAS system that monitors GPS constellation of satellites. The WAAS-NIES subsystem hardware is scalable to meet requirements for simulating the WAAS system. The software of the WAAS-NIES subsystem is portable to other platforms (such as a PC) to allow re-use in smaller-scale simulations for single-task use.

2.1 WAAS-NIES System ArchitectureThe WAAS-NIES system architecture is defined in the WAAS-NIES System Definition Document. The hardware architecture is shown below:

Figure 2.1-1 WAAS-NIES Hardware Architecture

2.2 Assumptions and ConstraintsAssumptions and constraints are provided in the WAAS-NIES System Definition Document.

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2.3 User CharacteristicsIt is assumed that the users of the WAAS-NIES system will be specifically trained for its use.

2.4 Assumptions and Dependencies

The WAAS-NIES user interface is supplied by the Environment Simulator.The WAAS-NIES will be used in the future to demonstrate the potential to achieve vertical position accuracies of meters at specific user sites.

3. RequirementsThis section of the document lists specific requirements for the Wide Area Augmentation System Infrastructure Environment Simulator. Requirements are divided into the following sections:

1. User requirements: These are requirements written from the point of view of the WAAS-NIES end users and include any user interface requirements.

2. System requirements: These are detailed specifications describing the functions the WAAS-NIES must perform (functional requirements) and how well they must be performed (performance requirements).

3. Interface requirements: These are requirements for interfaces between the WAAS-NIES and other systems (external interface) and requirements between major subsystems within the WAAS-NIES (internal interfaces).

Legend:C = CriticalE = EssentialN = Non-Essential

3.1 User Requirements

Requirement ID

Criticality Requirement Rationale Subsystem allocation:

SRD-001 E The WAAS-NIES shall verify that the user selected software version is loaded during initialization.

Different users may perform various functions on the WAAS-NIES, thus may require different software versions

SW

SRD-002 E The WAAS-NIES shall allow user control of software version selection through external input during simulation initialization.

The Environment Simulator provides the WAAS-NIES user interface for software version control.

SW

SRD-003 C The WAAS-NIES shall allow user control to input coordinates.

The user will have the capability to input coordinates within the specified range.

SW

SRD-004 E The WAAS-NIES shall allow user to visualize real time feedback.

The system will update often, to allow the user to see the status of the activities being performed.

SW

SRD-005 C The WAAS-NIES shall allow the user to select input/output directory files.

The user will be able to select from existing files, instead of deriving coordinate points.

SW

SRD-006 C The WAAS system should operate on Windows 98-XP platforms.

The simulator must operate on the specified platform, because it is not capable to operate on other systems.

SW

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3.2 System Requirements

Functional Requirements

Requirement ID

Criticality Requirement Rationale Subsystem allocation:

SRD-007 C WAAS-NIES shall simulate communication between the WMS and satellites in space.

This is required for the signals to be sent between the satellites and the ground stations. This is key for the WAAS system.

SW

SRD-008 C WAAS-NIES shall have simulation of all 25 WRS sites.

There are 25 WRSs in the U.S.

HW, SW

SRD-009 E A development environment shall be made available for the development of WAAS-NIES software.

Required for the software maintenance of WAAS-NIES applications software and databases.

HW, SW

SRD-010 C The WAAS-NIES shall simulate 2 WMSs.

SW

SRD-011 C The WAAS-NIES development environment shall be isolated from the simulation environment during simulation sessions.

Precludes the development environment from inadvertently affecting simulation sessions.

HW, SW

SRD-012 E Storage shall be provided for up to 10 WAAS-NIES application software versions

Required to save different versions for use by different users.

HW

SRD-013 E The storage for the WAAS-NIES application software versions and the visual model database versions shall be accessible during WAAS-NIES simulation initialization for download of the user-specified version WAAS-NIES application software and user-specified visual model database.

User must be able to define the version of software needed for each simulation session.

HW, SW

SRD-014 C The WAAS-NEIS shall provide an accurate simulation of the selected segment within the WAAS.

Signal transmission and reception records will be accessible for user simulation sessions.

SW

SRD-015 C The WAAS-NIES shall provide the simulation capability to detect and report interference between two designated signals.

SW

SRD-016 C The WAAS-NIES shall provide the capability to accept celestial and target state data, and correlate the simulation of sun glare with this data.

Assumes that the Environment Simulator provides celestial and target state data.

SW

SRD-017 C The WAAS-NIES shall allow custom shading of vertices and pixels.

To render a realistic visual model of complex objects within the system.

HW

SRD-018 E The WAAS-NIES shall provide the capability to update the computer image generation hardware.

Maintainability and supportability requirement.

HW

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SRD-019 C The WAAS-NIES shall receive input signals from the data file or manually.

The user will select the data input file or will type in the coordinates within range.

SW

SRD-020 C The WAAS-NIES shall initiate the environment simulator to utilize the input signal.

The environment simulator is needed to simulate the error (i.e. ionospheric) from the environment.

SW

SRD-021 C The WAAS-NIES shall receive WRS locations from the input files.

The location of each WRS is needed to calculate the delta error and should be provided.

SW

SRD-022 C The WAAS-NIES shall gather the signals from each WMS location.

The simulated WRS sites all collect data about the signal. The simulated WMSs need to process all the data from the WRSs.

SW

SRD-023 C The WAAS-NIES shall calculate error.

The purpose of the WAAS-NIES is to use the information from the simulated WRS sites to calculate the delta error in the signal.

SW

SRD-024 C The WAAS-NIES shall create and send augmentation message to the display area and satellite.

These messages are sent, to enable the GUI to be created for the user, and also to send output data to the satellite.

SW

SRD-025 C The WAAS-NIES shall provide a GUI to show graphical representation to the user.

The user will be able to view the graph of plotted coordinate points, in order to compare the environment versus the input points.

SW

SRD-026 E The WAAS-NIES shall save graphs as a JPEG file.

This important so that the files will occupy minimal disk space and accessible on any PC.

SW/HW

Performance Requirements

SRD-027 C WAAS-NIES will be able to send GPS information to simulated spacecrafts with accuracy of meters.

The Environment Simulator provides the WSP user interface for signal reception control

SW

SRD-028 C The WAAS-NIES must be designed to operate at 70% of the processor, memory, and input/output capability.

Spare capacity is required to keep the simulator operating at peak functionality and to allow resources for maintenance.

HW

SRD-029 C The WAAS-NIES shall provide the capability to detect and report collisions between two designated paths of signals.

The Environment Simulator provides the WSP user interface for signal reception control

HW, SW

SRD-030 E The WAAS-NIES shall be designed for 150% expandability.

To meet the expandability requirement to be able to add more satellites.

HW, SW

SRD-031 E The WAAS-NIES shall receive multiple reports, simultaneously,

The user will be able to view the occurring activities while

SW

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while scanning. the system continues to function.

SRD-032 E The WAAS-NIES shall refresh every 10 seconds.

The display will be updated so that the user can view any changes being made.

SW

SRD-033 E The WAAS-NIES shall be user friendly.

The simulator will be easy for users to use with minimal training.

SW

SRD-034 E The WAAS-NIES shall be capable of storing reports.

The system will need to store reports, so that the data can be retrieved at a later date.

SW

SRD-035 E The WAAS-NIES shall regulate data settings based on user input,

The user will be allowed to input data, but within the specified range, in order to produce valuable results, i.e. graphs.

SW

3.3 Interface Requirements

Requirement ID

Criticality Requirement Rationale Subsystem allocation:

SRD-036 E WAAS-NIES will come with a manual and help software to help the user.

The simulator should not be complex and be able to have material to help users. A detailed read-me file could take the place of the help file.

HW

SRD-037 C The WAAS-NIES development system shall be isolated from the WAAS-NIES during simulation.

For isolation and security purposes.

HW, SW

SRD-038 C The WAAS-NIES shall be capable of outputting the rendered image data to the Environment Simulator.

To allow for future use of the image data by the Environment Simulator.

HW

SRD-040 E The WAAS-NIES shall receive signals from input data files.

The WAAS-NIES needs to interface with the input data files provided by the user.

SW

SRD-041 E The WAAS-NIES shall be capable of receiving signals through the GUI from the user input.

The GUI needs to be the prime interface between the user and WAAS-NIES.

SW

SRD-042 E The WAAS-NIES shall send reports to the output file.

Reports are sent to the output files so it can be stored in the system.

SW

SRD-043 E The WAAS-NIES shall send reports to the GUI.

Reports are sent to the user so that they can be viewed.

SW

4. AppendicesTBD

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