TABLE OF CONTENTS Lav R. Varshney and Sergio D. Servetto
School of Electrical and Computer Engineering
Cornell University, Ithaca, NY 14853
{lrv2@,servetto@ece.}cornell.edu
| Abstract | We consider the problem of reachback communication in sensor networks. In this problem, a large number of sensors are deployed on a field, to measure the state of some physical process that unfolds over the field and to then cooperatively send this information back to a distant receiver for further processing. We formulate the problem as a multiple-input, single-output (MISO) system, and develop a time-division scheme based on transmission of simulated radar echoes. Information is encoded in the spatial electromagnetic reflectivity function of virtual point reflectors, and decoded with a conventional range radar receiver. Transmitter diversity and the use of pulse compression radar waveforms are exploited for both increased reliability and increased data rate. Information theoretic and simulation-based performance characterizations are also presented. |
The problem of surveilling a scene from a distance arises in numerous contexts including disaster recovery, tactical battlefield assessment, and environmental monitoring, where proximate surveillance is not practical. Traditional methods of remote sensing have included imaging systems such as optical, multispectral, and synthetic aperture radar (SAR) [11]. Despite the prominent successes of these systems, the base sensing modalities suffer from shortcomings. When operating at great distances, these sensing modalities achieve low resolution. Furthermore, the types of physical processes that can be sensed at a distance are limited to phenomena that propagate over large distances, such as electromagnetic waves. Other...
