GSFC-STD-9100, LOW DENSITY PARITY CHECK CODE FOR RATE 7/8 (RELEASE PENDING) (1 MAY 2006)., The purpose of this document is to establish a common GSFC channel coding standard for bandwidth efficient spacecraft communications. Currently many Goddard missions use the concatenated Reed-Solomon and convolutional coding technique for space to ground links. While this standard has served NASA well in the past it is bandwidth inefficient. The need GSFC-STD-9100, Low Density Parity Check Code for Rate 7/8. for bandwidth efficiency has prompted the Microwave and Communication Systems Branch (Code 567) to search for a new channel code that require less bandwidth without paying a heavy penalty in power requirement and complexity. This document details the result of that search. It gives a technical description of this new channel coding called low density parity check (LDPC) coding (Section 5). A description of the baselined LDPC code is presented in Section 6 and it’s encoding in Section 7. However, the baselined code needs to be modified to ease implementations for current space and ground systems. This modification is the proposed standard and is described in Section 8. Section 9 outlines synchronization issues and the Sections 12 and 13 of the Appendices discusses complexity issues and performance testing respectively. The reader is assumed to have a basic understanding of channel coding theory (linear algebra also) and digital communications. (The reader is encouraged to review [7] for an overview of linear block codes).

NASA GSFC-STD-1000 (REV. A), RULES, DESIGN, DEVELOPMENT, VERIFICATION, AND OPERATION OF SPACE SYSTEMS (30 MAY 2005) [aka "GOLDEN RULES"]. Goddard Space Flight Center (GSFC) Rules are a high-level subset of all the design rules required for safety and mission success for all space flight products. These rules spell out the technical or design requirements that every Goddard project shall meet regardless of its implementation approach. GSFC Rules are not replacements for existing Goddard Procedures and Guidelines (GPGs) or NASA Procedures and Guidelines (NPGs). NPGs and GPGs are specific, detailed procedures for implementing NASA and Goddard policies, and as such they often address project management requirements per NASA Procedural Requirements (NPR) 7120.5 that do not fall within the scope of the GSFC Rules. Figure 1 provides a hierarchy of where the GSFC Rules fit within the Center’s larger collection of rules. Figure 2 illustrates the role the GSFC Rules play in the Goddard Open Learning Design (G.O.L.D.) approach to knowledge management. GSFC Rules are not intended to serve as a “cookbook” or “how-to” guide, but rather as another tool for assessing overall project risk and assuring mission success.

NASA GSFC-STD-1000 (REV. C.2), RULES, DESIGN, DEVELOPMENT, VERIFICATION, AND OPERATION OF SPACE SYSTEMS (12 DEC 2006) [aka "GOLDEN RULES"]., Goddard Space Flight Center (GSFC) Rules are a high-level subset of all the design rules required for safety and mission success for all space flight products. These rules spell out the technical or design requirements that every Goddard project shall meet regardless of its implementation approach. GSFC Rules are not replacements for existing Goddard Procedural Requirements (GPRs) or NASA Procedural Requirements (NPRs). NPRs and GPRs are specific, detailed procedures for implementing NASA and Goddard policies, and as such they often address project management requirements per NASA Procedural Requirement (NPR) 7120.5 that do not fall within the scope of the GSFC Rules. Figure 1 provides a hierarchy of where the GSFC Rules fit within the Center’s larger collection of rules. Figure 2 illustrates the role the GSFC Rules play in the Goddard Open Learning Design (G.O.L.D.) approach to knowledge management. GSFC Rules are not intended to serve as a “cookbook” or “how-to” guide, but rather as another tool for assessing overall project risk and assuring mission success.

NASA GSFC-STD-1001, CRITERIA FOR FLIGHT PROJECT CRITICAL MILESTONE REVIEWS (NO DATE)., This document provides standard criteria for the flight project critical milestone reviews that comprise the Integrated Independent Reviews prescribed by GPR 8700.4. For each mission system review during the project lifecycle, the document describes the purpose, timing, objectives and success criteria.

NASA GSFC-STD-7000, GENERAL ENVIRONMENTAL VERIFICATION STANDARD (GEVS) FOR GSFC FLIGHT PROGRAMS AND PROJECTS (APR 2005) [SUPERSEDS GEVS-SE]., This standard provides requirements and guidelines for environmental verification programs for GSFC payloads, subsystems and components and describes methods for implementing those requirements. It contains a baseline for demonstrating by test or analysis the satisfactory performance of hardware in the expected mission environments, and that minimum workmanship standards have been met. It elaborates on those requirements, gives guideline test levels, provides guidance in the choice of test options, and describes acceptable test and analytical methods for implementing the requirements.

NASA GSFC-STD-9001, SPREAD SPECTRUM MODULATION FORMATS FOR NASA LINKS (20 NOV 2007)., This standard is published by GSFC, National Aeronautics and Space Administration (NASA) to provide uniform engineering and technical requirements for processes, procedures, practices, and methods that have been endorsed as standard for NASA programs and projects, including requirements for selection, application, and design criteria of an item. This standard establishes uniform requirements for applying pseudo-noise (PN) spreading in NASA links and describes the existing links that use PN spreading.