Date of Award

3-2006

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Electrical and Computer Engineering

First Advisor

Michael A. Temple, PhD

Abstract

Ultra wideband (UWB) signals typically occupy a very large spectral bandwidth resulting from extremely short duration pulses. Direct sequence spread spectrum (DSSS) signals typically occupy a large spectral bandwidth resulting from spreading methods. Both signals can be difficult to detect without having prior knowledge of their structure and/or existence. This research develops and evaluates techniques for the non-cooperative (non-matched filter) detection of such signals. Impulse-like UWB and DSSS signals are received in an Additive White Gaussian Noise (AWGN) channel and are assessed using a bandpass filtered, down-converting (BPF-D/C) channelized receiver architecture. Modeling and simulation are conducted to characterize BPF-D/C channelized receiver detection performance, which is compared with the performance of two other non-cooperative detection receivers: a previously-introduced down-converting (D/C) channelized receiver and a conventional radiometer. The BPF-D/C channelized receiver detection performance for both signals of interest is shown to depend on the initial phase of the down-conversion mixers. There are usually some combinations of signal-to-noise ratio (SNR) and channel bandwidth where the BPF-D/C channelized receiver outperforms the radiometer and D/C channelized receiver for a UWB pulse. For a DSSS waveform, detection performance using the BPF-D/C channelized receiver is consistently poorer than radiometric detection.

AFIT Designator

AFIT-GE-ENG-06-42

DTIC Accession Number

ADA447037

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