SBIR-STTR Award

This study will investigate the applicability of computer modeling and simulation to the analysis of personnel radio frequency (RF) radiation hazards. The final goal of this project is to design, develop, and produce a Windows based analysis tool to assist in the evaluation of RF hazards near an antenna. It will perform all routine analysis calculations, as well as near-field power density predictions to determine the hazard zone around that antenna in 3-dimensional space. It will also contain all reference material needed by an analyst. Most hazard analysis of RF systems start with a theoretical prediction of the hazard distance. This hazard distance is the distance to the point where the power density of the antenna's main beam falls off to the Permissible Exposure Limit (PEL) or Maximum Permissible Exposure (MPE) level. Presently, most analysts use simple inverse square law calculations and ignore near-field effects. This method frequently produces a gross overestimation of the hazard potential of the source. Antennas to be modeled in this SBIR include aperture (dish) antennas, wire antennas (dipole, monopole, yagi, log-periodic, curtain, etc), antenna arrays, and point sources. The option of including the effects of a ground plane will be included.

The hazard analysis and control of radio frequency (RF) systems is one of the least understood technical topics by USAF bioenvironmental engineers (BEEs) and technicians who need to evaluate these radiation hazards. Yet, this is one of the most controversial and feared sources of potential hazards in our complex electronic environment today Most AF health and safety managers are presently using crude estimates (e.g., inverse square law hazard distance calculations) method, and they require direct assistance in applying current methods in operational environments. At the completion of Phase II efforts, described herein, tools will be provided for all the information required for them to effectively manage these health and safety programs. RFHAT will guide them in analyzing RF systems, correctly estimating the hazard potential of emitters, provide a tutorial to help work through the more difficult concepts, and provide all the reference material needed to thoroughly complete site hazard evaluations The goal of Phase II of this SBIR is to continue to develop and produce a Windows-based program that calculates RF PELs (accomplished during Phase I), estimates field strengths for several antenna types, provides a tutorial on RF hazard assessment, and provides reference material required to perform a personal hazard assessment. It will be delivered on CD or Jazz disk and made available for hosting on AL's Web page