Free Space Optics (FSO) technology was originally envisioned to be a viable solution for the provision of high
bandwidth optical connectivity in the last mile of today's telecommunications infrastructure. Due to atmospheric
limitations inherent to FSO technology, FSO is now widely envisioned as a solution for the provision of high bandwidth,
temporary mobile communications links. The need for FSO communications links will increase as mobility is
introduced to this technology. In this paper, a theoretical solution for adding mobility to FSO communication links is
introduced. Three-dimensional power estimation studies are presented to represent mobile FSO transmission under
various weather conditions. Three wavelengths, 0.85, 1.55 and 10 um, are tested and compared to illustrate the pros and
cons of each source wavelength used for transmission, depending on prevalent weather conditions and atmospheric
turbulence conditions. A simulation analysis of the transmission properties of the source wavelengths used in the study
is shown.
Government funding for the security at shipping facilities and ports is limited so there is a need for low cost scalable
security systems. With over 20 million sea, truck, and rail containers entering the United States every year, these
facilities pose a large risk to security. Securing these facilities and monitoring the variety of traffic that enter and leave
is a major task. To accomplish this, the authors have developed and fielded a low cost fully distributed building block
approach to port security at the inland Port of Catoosa in Oklahoma. Based on prior work accomplished in the design
and fielding of an intelligent transportation system in the United States, functional building blocks, (e.g. Network,
Camera, Sensor, Display, and Operator Console blocks) can be assembled, mixed and matched, and scaled to provide a
comprehensive security system. The following functions are demonstrated and scaled through analysis and
demonstration: Barge tracking, credential checking, container inventory, vehicle tracking, and situational awareness.
The concept behind this research is "any operator on any console can control any device at any time."
KEYWORDS: Cameras, Video, Video surveillance, Information technology, Network security, Control systems, Defense and security, Sensors, Databases, Transportation security
With over 360 ports of entry and 20 million sea, truck, and rail containers entering the United States every year, port
facilities pose a large risk to security. Securing these ports and monitoring the variety of traffic that enter and leave is a
major task. To accomplish this, the authors propose a fully distributed building block approach to port security. Based
on prior work accomplished in the design and fielding of an intelligent transportation system in the United States,
building blocks can be assembled, mixed and matched, and scaled to provide a comprehensive security system. Network
blocks, surveillance blocks, sensor blocks, and display blocks will be developed and demonstrated in the lab, and at an
inland port. The following functions will be demonstrated and scaled through analysis and demonstration: Barge
tracking, credential checking, container inventory, vehicle tracking, and situational awareness. The concept behind this
research is "any operator on any console can control any device at any time."
Significant research efforts are underway to investigate the application of Free-Space Optics (FSO) for the provision
of high-bandwidth communications links between mobile platforms. The use of FSO between mobile platforms
introduces several interesting challenges in addition to those found in traditional fixed link FSO systems. In this
paper, some of the major hurdles facing fixed FSO communications that carry over into links between mobile
platforms are analyzed. These topics include: issues with alignment and tracking, an investigation into the weather
and its affect on the link, and a study of the feasibility of having uninterrupted communications links. Other topics
presented unique to mobile applications include: the security risks during link alignment, maintaining the link while
tracking and optical power and beam divergence variations that are introduced into the system. In this paper the
results from simulation work performed on some of these issues along with proposed solutions to the challenges are
presented.
In this paper, a comparison of the physical security aspects of a time division multiplexed (TDM) passive optical
network (PON) and a proposed wavelength hopping passive optical network (WH-PON) is presented. Simulated results
of an eavesdropping attempt in both networks are presented. The introduction of a WH-PON will demonstrate how
physical layer security can be introduced to a PON architecture through the use of a pair of matched tunable lasers in the
optical line terminal (OLT). These matched tunable lasers allow for the creation of a secure point-to-point optical link
between the OLT and the end user, without the need for a unique optical transmitter for each end user. The simulation
results presented will demonstrate the operation of each PON architecture, as well as the physical immunity to
eavesdropping that the WH-PON architecture introduces.
KEYWORDS: Video surveillance, Video, Cameras, Surveillance, Network security, Information security, Defense and security, Global Positioning System, Control systems, Sensors
With the ever present threat to commerce, both politically and economically, technological innovations provide a means to secure the transportation infrastructure that will allow efficient and uninterrupted freight-flow operations for trade. Currently, freight coming into United States ports is "spot checked" upon arrival and stored in a container yard while awaiting the next mode of transportation. For the most part, only fences and security patrols protect these container storage yards. To augment these measures, the authors propose the use of aerial surveillance vehicles equipped with video cameras and wireless video downlinks to provide a birds-eye view of port facilities to security control centers and security patrols on the ground. The initial investigation described in this paper demonstrates the use of unmanned aerial surveillance vehicles as a viable method for providing video surveillance of container storage yards. This research provides the foundation for a follow-on project to use autonomous aerial surveillance vehicles coordinated with autonomous ground surveillance vehicles for enhanced port security applications.
Free-space optics (FSO), or Optical Wireless, is an unlicensed line-of-sight technology that uses modulated lasers to
transmit information through the atmosphere. By using light beams, FSO can transmit and receive data, voice, and
video, information through the air. FSO provides data rates ranging from 100Mbps to 2.5Gbps. In most applications,
FSO transceivers normally remain in a static location to ensure continuous line of sight and to maintain accurate
alignment. One current challenge facing FSO technology is the desire to implement mobility. As a potential solution,
this study introduces an auto-tracking system that will achieve and maintain alignment between two mobile FSO nodes.
This auto-tracking system can be used in many different applications, such as reducing the time needed to achieve
alignment of an FSO link, and maintaining a link between an aircraft and a stationary command post to exchange real-time
video and data with high-speed laser communications. After link initiation, the auto-tracking system application
will send steering commands back to the positioning gimbal. These steering commands are determined by feedback
from Position Sensing Diodes (PSDs). The proposed FSO auto-tracking system provides optical beam steering and
capturing mechanisms to provide tracking between two transceivers, either fixed or mobile. In this paper, we illustrate
the feasibility of such a system and present experimental results for a source aligned with a PSD in a mobile
environment.
KEYWORDS: Free space optics, Detection and tracking algorithms, Unmanned aerial vehicles, Receivers, Transmitters, Mobile communications, Free space optical communications, Optical simulations, Algorithm development, Global Positioning System
Free-space optical (FSO) communications links are envisioned as a viable option for the provision of temporary high-bandwidth
communication links between moving platforms, especially for deployment in battlefield situations. For
successful deployment in such real-time environments, fast and accurate alignment and tracking of the FSO equipment is
essential. In this paper, a two-wavelength diversity scheme using 1.55 μm and 10 μm is investigated in conjunction with
a previously described tracking algorithm to maintain line-of-sight connectivity battlefield scenarios. An analytical
model of a mobile FSO communications link is described. Following the analytical model, simulation results are
presented for an FSO link between an unmanned aerial surveillance vehicle, the Global Hawk, with a mobile ground
vehicle, an M1 Abrams Main Battle Tank. The scenario is analyzed under varying weather conditions to verify
continuous connectivity is available through the tracking algorithm. Simulation results are generated to describe the
performance of the tracking algorithm with respect to both received optical power levels and variations in beam
divergence. Advances to any proposed tracking algorithm due to these power and divergence variations are described
for future tracking algorithm development.
KEYWORDS: Free space optics, Unmanned aerial vehicles, Video surveillance, Detection and tracking algorithms, Telecommunications, Video, Mobile communications, Surveillance, Receivers, Transceivers
Free Space Optics (FSO) technology is currently in use to solve the last-mile problem in telecommunication systems by
offering higher bandwidth than wired or wireless connections when optical fiber is not available. Incorporating mobility
into FSO technology can contribute to growth in its utility. Tracking and alignment are two big challenges for mobile
FSO communications. In this paper, we present a theoretical approach for mobile FSO networks between Unmanned
Aerial Vehicles (UAVs), manned aerial vehicles, and ground vehicles. We introduce tracking algorithms for achieving
Line of Sight (LOS) connectivity and present analytical results. Two scenarios are studied in this paper: 1 - An
unmanned aerial surveillance vehicle, the Global Hawk, with a stationary ground vehicle, an M1 Abrams Main Battle
Tank, and 2 - a manned aerial surveillance vehicle, the E-3A Airborne Warning and Control System (AWACS), with an
unmanned combat aerial vehicle, the Joint Unmanned Combat Air System (J-UCAS). After initial vehicle locations
have been coordinated, the tracking algorithm will steer the gimbals to maintain connectivity between the two vehicles
and allow high-speed communications to occur. Using this algorithm, data, voice, and video can be sent via the FSO
connection from one vehicle to the other vehicle.
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