Rapidly Deployable Broadband Communications for Disaster Response

We present the design of a rapidly deployable backb one communications system for disaster response. Although work on the system began in 2000, it is in tended for disasters like those that occurred on Se ptember 11, 2001. It illuminates the disaster site with RF that supports high-capacity (100 base T or Gigabit Ethe rnet) links to the outside world. Operating initially at 28 GHz with a 5 GHz version now under construction, it uses non -line-of-sight (NLOS) “bounce paths” of opportunity to provide cov erage at shadowed locations. Since at these freque ncies most building walls and terrain features are electro mag netically rough, the radio paths are highly dispers iv and require careful characterization for optimum radio performa nce. In order to identify such paths of opportunit y and study their characteristics, we developed an impulse chan nel sounder based on ultra wideband technology. Whe n perfected, it will allow our system to identify the best path and set the radio parameters for optimum q ality of service. Since the channels encountered in a given disaster situation may differ significantly from t hose anticipated or previously experienced, our goal is to use the s ounder output to drive a cognitive engine that will control the radios. We present our genetic algorithm based imp le entation of a cognitive radio and outline our pl ans for implementation and testing a cognitive version of o ur system in the 5 GHz band.