Steve Gifford

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In this work, we apply watermarking to the physical layer of the wireless baseband modulation waveform, with the motivation to improve flexibility and efficiency of authentication processes in a secure wireless network. We present two baseband watermarking methods, called constellation dithering (CD) and baud dithering (BD), applied to orthogonal frequency(More)
In this paper, we present an object-oriented approach for using real-world location data for the evaluation of evacuation behavior models. When constructing a new building or planning, how an existing one is used, safe evacuation is extremely important. Currently, many models exist to simulate a building evacuation, using information from the layout of(More)
Broadband wireless services are typically considered usable in limited mobility conditions (fixed access or at pedestrian speeds). In this paper, we present a method for time and frequency synchronization of broadband OFDM for mobile ad hoc networking systems, where each node randomly and rapidly changes location. The proposed method is robust in Rayleigh(More)
# In this paper we develop multiple antenna space-time decoding techniques that enable very high capacities in mobile wireless systems. The method can be implemented in small form factor handheld software defined radios. We derive a low-complexity iterative decoding scheme based on diagonal or Cayley differential encoders for multi-input multi-output (MIMO)(More)
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