Mirchandani, Chandru | Search NASA

NASA NTRS1995

Decision process for effective system reuse

The speed of growth in high technology differs for software, hardware and firmware. Hardware innovations come in leaps, as opposed to the gradual improvements in software and firmware technologies. This inhibits the full utilization of the hardware advances and reduces the cost benefit ratio of high technology ventures. The Microelectronics Systems Branch has committed its resources to use the look ahead technique whereby the technology is researched in its use, current development track and its future capabilities. This knowledge is used to meet the requirements of the space program not only in the nineties but also through 2005. This paper illustrates Analytical Hierarchy Process techniques used effectively and very successfully to support projects reusing systems with predicted enhancements.

Mirchandani, Chandru↗

NASA NTRS1994

Spacecraft Data Simulator for the test of level zero processing systems

The Microelectronic Systems Branch (MSB) at Goddard Space Flight Center (GSFC) has developed a Spacecraft Data Simulator (SDS) to support the development, test, and verification of prototype and production Level Zero Processing (LZP) systems. Based on a disk array system, the SDS is capable of generating large test data sets up to 5 Gigabytes and outputting serial test data at rates up to 80 Mbps. The SDS supports data formats including NASA Communication (Nascom) blocks, Consultative Committee for Space Data System (CCSDS) Version 1 & 2 frames and packets, and all the Advanced Orbiting Systems (AOS) services. The capability to simulate both sequential and non-sequential time-ordered downlink data streams with errors and gaps is crucial to test LZP systems. This paper describes the system architecture, hardware and software designs, and test data designs. Examples of test data designs are included to illustrate the application of the SDS.

Shi, Jeff↗