This project is funded under the National Science Foundation's (NSF) Small Business Innovation Research (SBIR) program, which is designed to provide an opportunity for small business, particularly the small high technology firm, to participate in NSF research. Phase I of the SBIR program serves as a filter to select promising proposals and determine if the firm can do high quality research. Phase II is the principal research project. Phase III is the conversion of the NSF-funded research into commercial applications and technological innovation supported by follow-on private venture capital or other non-federal financing. This Phase I project addresses multipath fading on radio channels for high speed digital communications. The principal investigator is investigating a new approach that adapts the system data rate to the time-varying signal-to-noise ratio at the radio receiver. The objectives are to determine the feasibility of rate changing algorithms and adaptive synchronization; develop a measure of waiting time performance; and determine the effects of queueing, a noisy feedback channel, rate changing overhead, and propagation delay. The approach employs trellis coded modulation in an adaptive scheme where the data rate varies by changing the number of bits per channel symbol.
