Penn State University ARL Utilizing
EB Propsim Channel Emulator in
State-of-the-Art Ad-Hoc Network
Test System Success Story

The Pennsylvania State University Applied Research Laboratory (PSU/ARL) serves as a university center of research excellence in naval sciences and technologies.  Within PSU/ARL, the Electromagnetic and Geospatial Systems Division (EGSD) has two purposes.

First, the Applied Electromagnetics (AE) Department develops advanced technologies focused on the transmission, reception, characterization, simulation, and test and evaluation of radio frequency signals. Additionally, the Geospatial, Imaging and Tactical Systems Department (GITS) analyzes, designs, develops and prototypes Geospatial Information systems for all Department of Defense (DoD) services, national intelligence and other government agencies. Operating as one cohesive unit, one of the EGSD's missions is to test and evaluate microwave communication equipment in realistic environments for a variety of applications including, but not limited to antenna design, simulation and analysis, radio frequency mission planning, pattern recognition, and science and technology development for test evaluation.

The Challenge

For one of its projects, the EGSD was tasked with developing a Communications Environment Emulator (CEE) system that would provide a realistic simulation of communication networks under varying terrain, urban landscape and operating scenario conditions. Simulating ad-hoc communication networks within urban environments is a capability of increasing importance to determine how devices will perform in real world environments; however, disseminating RF signals within urban and other mixed signal environments presents a challenge.

Urban and other mixed environments become more complex as the depth of penetration into the urban environment increases. Additionally, under complex conditions, the precise knowledge of antenna orientation and elevation may not be realistic for mobile cellular applications. While a number of generally accepted channel models are available for use, they suffer from limitations such as increasing costs and producing unrealistic results as the environment becomes more complex. For these reasons, channel impairments in a complex urban environment are generally modeled as statistical processes based on various accepted distributions.

EGSD needed to develop a system that would create scenario-driven simulations reflecting network conditions as one or more system elements moved across various types of terrain and urban environments to illustrate local system RF losses and antenna pattern effects. As the cellular testbed evolved, EGSD required a design that was flexible and modular to allow the system to expand and reconfigure. Units needed to be wirelessly connected to the simulation environment to permit rapid, efficient use of unmodified units.

The Solution

EGSD needed a partner to help construct a solution that would allow the research organization to develop and test various scenarios that simulate realistic, complex environments to produce more accurate results. It selected the EB Propsim C8 System because it would provide High-Fidelity simulation of channel propagation characteristics and impairments that would include space-loss, multipath fading and noise injections in the simulated environments.

With the EB Propsim C8 multi-channel emulator, EGSD developed a hardware-in-the-loop channel and environment simulation (CES) system for testing and evaluating microwave communication equipment in realistic environments. The system is comprised of the EB Propsim C8, an ArcGIS interface, and a hardware and control network.

The Benefits

EGSD decided to move forward with EB for the flexibility channel modeling tools, powerful fading emulation capabilities and simplified construction that the EB Propsim C8 multi-channel emulator provides. The flexibility of the EB Propsim C8 multi-channel emulator allowed PSU/ARL to develop the required algorithms to adapt EB's model for selected scenarios. While the EB Propsim C8 emulator is used for the actual channel simulation, the CES team also developed a hardware and software "wrapper" for the C8, providing a customized emulation environment that can be scaled and adjusted to a wide range of test units, environments and operational scenarios. EB's emulator is treated as an embedded channel simulation engine providing the needed channel fading and path loss while the ArcGIS interface provides the user with a scenario editor, terrain and urban datasets, and controls for the system. This method permits the recall of previous run tests and scenarios for reliable and repeatable testing.

By using this solution, PSU/ARL developed a system that they have delivered to a defense organization which offers a realistic simulation of ad-hoc communication networks between multiple platforms under varying terrain, urban landscapes and operating scenario conditions.