Original Date: 05/01/2000
Revision Date: 01/18/2007
Best Practice : Modeling and Simulation for Requirements Definition
Previously, Northrop Grumman Defensive Systems Division (DSD) used past experience and limited analysis to formulate the system requirements for electronic warfare systems. Typically, the system requirements were either underestimated leading to poor system performance, or overestimated leading to excessive system cost. Today, the company combines digital modeling and simulation with engineering analysis to develop and ensure accurate system requirements.
Building on its 18-plus years of experience in modeling and simulations, Northrop Grumman DSD developed a library of modeling and simulation tools to support its system requirements definition tasks. These tools have enabled the company to reduce the cost of test and evaluation activities. The specifics of electronic warfare systems require knowledge in the fundamental areas where the simulation tools will be applied: the phenomenology, engagement, and mission levels. Although system requirements are derived from all sources, they generally are processed through these levels of simulation.
Using primarily government sponsored and supported models, Northrop Grumman DSD is developing models and methodologies to address specific issues and pursue multiple approaches to confirm, validate, and cross-check the results. Figure 2-2 shows a high-level block diagram for countermeasure technique development. Modeling in the phenomenology domain is geared toward physical assessments and environmental impacts on system performance such as effects due to clutter, weather, terrain, aerodynamics, or obscuration. System effectiveness requirements are derived through direct interaction with each applicable weapon system through all phases of an engagement, including search, acquisition, target tracking, missile guidance, and intercept. Operational system requirements are established by modeling a representative operational mission scenario and observing multiple threat handling characteristics and platform survivability.
Each flight test costs approximately $50,000 to $60,000. Since implementing the modeling and simulation for requirements definition, Northrop Grumman DSD has significantly improved the performance level of systems being designed and reduced the number of flight tests required.
Figure 2-2. Countermeasures Technique Development
For more information see the
Point of Contact for this survey.