Southwest Research Institute 1996 Annual Report

The Institute is recognized worldwide as a leader in radio frequency (RF) signal exploitation and geolocation system development. An experienced technical staff coupled with excellent laboratories and test facilities allows SwRI to address a wide variety of requirements for clients including direction finding (DF) and radiolocation, automatic signal processing and recognition, automated spectrum surveillance, and satellite-based geolocation. Advanced systems for land-based, shipboard, and airborne applications are developed by SwRI for government, military, and commercial clients in the U.S. and around the world.

Narrowband and wideband electronic support systems are designed and developed using modern, high-speed digital signal processing hardware. The Institute's wideband signal intercept systems and narrowband signal recognizers use advanced signal processing algorithms to provide automated intercept, recognition, analysis, demodulation, and location of communications signals. Emphasis is placed on designing systems around commercial off-the-shelf hardware using open hardware and software architectures. The result is a cost-effective solution to client requirements and the ability to easily expand or upgrade systems.

The Institute continues to design, develop, and produce numerous high frequency, very high frequency, and ultra high frequency ground-based and shipboard DF systems for intercepting and locating communications signals. The most recent shipboard DF program is the Cooperative Outboard Logistics Upgrade, a joint effort between the U.S. and U.K. Navies. Under this international program, SwRI will design and develop specialized DF antennas for destroyers and frigates. Related engineering support capabilities include performance analysis of DF geolocation networks, signal propagation prediction, network design assistance, and DF processing and calibration techniques tailored for sites where antenna patterns are highly distorted due to electromagnetic reradiation.

The Institute-developed SABER system (Situational Awareness BEacon with Reply) is an advanced combat identification and situational awareness system used to prevent friendly fire incidents. This year, the system was installed on Army Blackhawk and Navy Seahawk helicopters to support military exercises. It was also installed on four M1 Abrams tanks, a high mobility multipurpose wheeled vehicle (HMMWV), and a light-armored vehicle (LAV) during All-Services Combat Identification Evaluation Team exercises at Camp Shelby, Mississippi.The green, orange, purple, and blue symbols on the map represent the tanks, while the yellow and red symbols are the LAV and HMMWV, respectively. The LAV, although "friendly," was not part of the red team and was added to the scenario to test SABER. SABER correctly identified the LAV as friendly, allowing the vehicle to leave the battle area without drawing the fire of the red team.

Using powerful technologies such as the Global Positioning System, digitally synthesized communications signals, digital mapping, and over-the-horizon satellite communications, SwRI has developed advanced combat identification, target recognition, and situational awareness equipment to support the digitized battlefield. The SwRI-developed SABER (Situational Awareness BEacon with Reply) system is recognized as a U.S. Department of Defense Advanced Concept Technology Demonstration Program. This year, SABER was used for the second consecutive year in the All-Services Combat Identification Evaluation Team exercises at Camp Shelby, Mississippi. This event followed a six-month field deployment of SABER with the U.S. Navy and the 22nd Marine Expeditionary Unit. During the field trial, SABER reported the geolocation of air, land, and sea assets in support of NATO peacekeeping efforts off the coast of the former Yugoslavia and the evacuation of non-combatants from Monrovia during the Liberian crisis.

The Institute continues to improve automated spectrum surveillance and signal exploitation techniques through the use of specialized software designed to operate with state-of-the-art commercial test equipment such as the Hewlett Packard HP3238S spectrum analyzer. For this and similar spectrum surveillance programs, SwRI has developed custom software and hardware for a variety of computer platforms to meet specific client needs. Examples include specialized antennas and RF distribution networks, high-resolution color RF spectrum displays, geographic and architectural map displays, and custom operating functions.

The design of electronic circuits that require very low power for operation is an active development area at SwRI. An example is surveillance equipment that must often operate from battery power in remote locations. For one such application, SwRI designed a very high frequency radio receiver and digital decoder that operates on five volts and one-and-a-half milliamperes. This power requirement is about one-fourth that of similar, commercially available receivers. Low-power operation is obtained through a combination of discrete analog circuit design and complementary metal oxide semiconductor digital integrated circuits, while small size is achieved by using subminiature components and surface-mount technology.

The Institute's considerable experience in magnetic resonance (MR) techniques includes nuclear MR, nuclear quadrupole resonance, and electron paramagnetic resonance. On-line, real-time MR instrumentation developed by SwRI was recently installed in a major manufacturer's high-volume production facility to accurately monitor and control the moisture in a consumer product. The MR sensor increased moisture control accuracy by a factor of four over existing methods and has proven reliable in a high-temperature industrial environment.

In other research, Institute scientists determined that MR is capable of detecting hydrates and paraffins in gas-oil-water mixtures, a necessary activity during oil and gas recovery and transmission in cold and deep sea environments. Results of an internal research study also proved MR useful for measuring the composition, heating values, and compressibility factors of both liquified and compressed natural gases in single and multiphase states.

Institute scientists are identifying and analyzing propagation characteristics of acoustic and seismic waves to better predict permeability distribution in a fractured reservoir owned by Union Pacific Resources. This work is part of a three-year research program to characterize the fracture systems of oil reservoirs, sponsored by the National Institute for Petroleum and Energy Research in Bartlesville, Oklahoma.

Copyright© 1996 by Southwest Research Institute. All rights reserved under U.S. Copyright Law and International Conventions. No part of this publication may be reproduced in any form or by any means, electronic or mechanical, including photocopying, without permission in writing from the publisher. All inquiries should be addressed to Communications Department, Southwest Research Institute, P.O. Drawer 28510, San Antonio, Texas 78228-0510.

Signal Exploitation, Geolocation, and Electronic Systems and Instrumentation