A hybrid link, consisting of a high bandwidth free space optical link and a lower rate RF link can provide high speed yet robust connectivity. In the past, the constituting links have been considered separately with respect to modulation and coding. We propose the following research under the revised budget for this project:
1) Investigate joint coding and modulation techniques for the hybrid link including joint demodulation and decoding with turbo codes, LPDC codes, and trellis codes. Important design aspects of these techniques will be considered. Optimal detection/decoding techniques will be studied. Efficient data sharing between the optical and RF links will be investigated. [Reduction in senior personnel support results in less attention to certain design aspects of the codes and less development of suboptimal but low complexity techniques.]
2) Develop an experimental testbed for studying the hybrid link and for validating the novel data transmission results. [Unchanged from original proposal.]
Intellectual merit: Novel approaches to joint modulation and coding will be produced. Laboratory work will complement and strengthen theoretical work. Significant new ideas and techniques will be developed and published. [Unchanged from original proposal.]
Broader impacts: Outcomes will be applicable to other types of hybrid links and will lead to performance improvements. The research will strengthen faculty collaboration at NMSU and build infrastructure and expertise in optics, communications and RF areas. Education is an important aspect of the program and graduate students will be trained in communications related fields. [Undergraduate student training has been removed.]
