Title

New results in distributed detection and data fusion for target tracking

Date of Completion

January 1995

Keywords

Engineering, Electronics and Electrical

Degree

Ph.D.

Abstract

Distributed detection, data fusion and tracking are intimately related, even though results on their inter-relationship are relatively recent. In this dissertation we analyze three different aspects of these inter-relationship.^ First we propose a new scheme for distributed detection based on a "censoring" or "send/no-send" idea. The sensors are assumed to "censor" their observations so that each sensor sends to the fusion center only "informative" observations, and leaves those deemed "uninformative" untransmitted. We derive the properties of these optimal no-send regions and the performance of such censored schemes.^ After that we address one problem associated with fusion of measurements from non co-located sensors. If members of a suite of sensors from which fusion is to be carried out are not co-located, it is unreasonable to assume that they share a common resolution cell grid; this is generally ignored in the data fusion community. We explore the effects of such "noncoincidence", and we find that what at first seems to be a problem can in fact be exploited to our advantage. The idea is that a target is known to be confined to an intersection of overlapping resolution cells, and this overlap is generally small. Further, we look into the idea of "single-sensor" noncoincidence.^ Finally we explore fusion as it pertains to pulse shape selection. It is commonly understood that in active detection systems constant-frequency (CW) pulses correspond to good Doppler but poor delay resolution capability; and that linearly-swept frequency (FM) pulses have the opposite behavior. Many systems are capable of both types of operation, and hence in this chapter the fusion of such pulses is examined. It is discovered that in many situations the features complement in such a way that tracking performance using a combined CW-FM pulse is improved when compared to a scheme using only CW or FM pulses. Also investigated are alternating-pulse schemes, and while these are suboptimal, their performances appear robust. ^