Note: Descriptions are shown in the official language in which they were submitted.
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TITLE
[0001] Sensing scanning system
FIELD
[0002] A scanning system for the collection, analysis and distribution of
remotely sensed
data related to an event from both static and moving platforms.
BACKGROUND
[0003] Collecting, analyzing and extracting remotely sensed data by digital
means has
been done for decades as is demonstrated by the substantial collection of
satellite imagery,
scientific and military use of radars, and the monitoring of weather
conditions. See, for
example, U.S. patent no. 7,106,333 (Milinusic) entitled "Surveillance System",
and U.S.
patent no. 6,989,745 (Milinusic et al.) entitled "Sensor Device for Use in
Surveillance
System".
[0004] There exists a need to extract specific features, events, or
characteristics of motion
present in objects within a substantially large volume. Examples include
detection of targets
such as moving vehicles from 65,000 ft high-flying surveillance UAV, or
vehicles and
individuals from the surveillance coverage of a large panoramic border area or
cityscape. In
each case, from a static or moving platform thousands of targets, events, or
specific features
are required to be extracted effectively and efficiently from the large volume
of data.
SUMMARY
[0005] According to an aspect, there is provided a method of securing and
extracting
sequential sensor data, comprising the steps of. scanning a volume with at
least one
electromagnetic sensor to obtain multiple scans, each scan having at least one
different
characteristic to create a multiple scan sequence of the volume; extracting at
least one volume
subset from the multiple scan sequence containing at least one event
satisfying at least one
predetermined criterion; and analyzing the at least one volume subset to
classify the at least
one event using predetermined characteristics.
[0006] According to an aspect, there is provided a sensing scanning system
comprising a
scanner comprising at least one electromagnetic sensors. The scanner is
programmed to
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obtain multiple scans of a volume using the at least one electromagnetic
sensor. Each scan
has at least one different characteristic. A processor is connected to receive
the scans from
the scanner. The processor is programmed to compare the multiple scans from
the scanner to
identify events based on a change between the scans satisfying at least one
predetermined
criterion; extract a volume subset from the scans containing each event; and
analyze at least a
portion of the volume subset to characterize each event using predetermined
characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] These and other features will become more apparent from the following
description in which reference is made to the appended drawings, the drawings
are for the
purpose of illustration only and are not intended to be in any way limiting,
wherein:
FIG. 1 is a block diagram of a sensing scanning system.
FIG. 2 is a block diagram of a sensing scanning system with a user interface.
FIG. 3 is a block diagram depicting the scanning sequence.
FIG. 4 is a block diagram of a sensing scanning system with a secondary
system.
FIG. 5 is an alternate block diagram of a sensing scanning system with a
secondary system.
FIG. 6 is an alternate block diagram of a sensing scanning system.
2 0 DETAILED DESCRIPTION
[0008] A sensing scanning system generally identified by reference numeral 10
will now
be described with reference to FIG.1 through 6.
Structure and Relationship of Parts:
[0009] Referring to FIG. 1, sensing scanning system 10 includes a scanner 12
with
electromagnetic sensors 14. Scanner 12 may have one or more electromagnetic
sensors 14.
Scanner 12 is programmed to obtain multiple scans of a volume using
electromagnetic
sensors 14 to obtain scans having different characteristics.
[0010] In different embodiments, scanner 12 may have a single sensor 14 with a
series of
modifiers 16 for changing the characteristics of the successive scans, or
multiple sensors 12
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with a series of modifiers 16. Alternatively, each sensor 14 may be selected
for a specific
inherent or permanent modifier, where the desired characteristics determine
the types of
sensors that are selected. Different characteristics that may be used include
a difference in
space, time, electromagnetic polarization, electromagnetic phase,
electromagnetic amplitude,
and electromagnetic wavelength. Modifiers may include various types of
filters, such as
polarizers, phase shifters, or spectral filters.
[0011] In some embodiments, sensing scanning system 10 may be used for
observation of
a volume or area, such as for security purposes. Scanner 12 may be mounted on
stationary
platform or a moving platform for observing the volume. If a moving platform
is used, a
stabilization device or algorithm is preferably used to improve the quality of
the scans and
provide accurate geo-referencing. The various ways in which the teachings
contained herein
may be used will be recognized by those skilled in the art, and may include
uses such as
surveillance, search and rescue, situation awareness, ground characterization,
etc. In these
embodiments, sensing scanning system 10 may be referred to as a remote sensing
scanning
system. However, other embodiments may not be remote. Sensing scanning system
10 is
preferably designed to provide a user with the ability to identify possible
events of interest
that may be very numerous or very small relative to the size of the volume.
Thus, sensing
scanning system 10 may be used to obtain information of any type of volume
that is able to be
scanned whether at long range or at microscope scales.
[0012] Sensing scanning system 10 also includes a processor 18 that is
connected to
receive the scans from scanner 12. Processor 18 is programmed to compare the
multiple
scans received from scanner 12 to identify events. Referring to FIG. 3, a
multiple scan
sequence 20 obtained by sensors 14 of scanner 12 is shown having three scan
22, 24 and 26.
Referring to FIG. 1, an "event" is indicated by reference numeral 28. Events
28 are based on
a change between scans 22, 24, 26 that satisfy at least one predetermined
criterion
programmed into processor 18, and are generally detected by a difference in,
for example, the
luminance or amplitude of a pixel in an optical embodiment, or phase and
polarimetric angles
in a radio signal between the different scans. For example, if the difference
between the scans
is time, the predetermined criteria may relate to the movement of an object
having a specified
shape, color, size, etc. If the difference is the electromagnetic radiation
detected, the
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predetermined criteria may relate to a particular band of radiation being
absorbed, emitted or
reflected. Combinations of these various criteria and differences may also be
used to help
identify events of interest. Using both motion, detection as well as
Multispectral differentiation
increases the chance to narrow the detection of an event meeting very specific
characteristics.
For example, this could be the case of locating and tracking the smoke from
certain types of
fires based on their motion against the sky and their spectral signature, thus
differentiating
smoke from ,rubber tires versus industrial or forest fires. In the depicted
example, the
movement of a round object is the event that is detected.
[0013] Referring to FIG. 1, once event of interest 28 has been detected,
processor 18
extracts a volume subset 30 from scans 22, 24, 26 containing event 28.
Generally, a volume
subset 30 is extracted for each event 28. Volume subset 30 is then analyzed by
processor 18
to characterize or classify event 28 using predetermined characteristics. Only
a portion of
volume subset 30 may be analyzed, for example, the analysis may include only
event 28.
[0014] The particular type of analysis performed will depend on the
preferences of the
user. Analysis of volume subset 30 and event 28 may include categorizing the
event
according to predetermined characteristics. These may be based on, for
example, angular,
geographic, color, speed, size, polarization, and other measures derived from
the differences
between the scans and the modifiers or inherent capabilities of the scans. As
volume subset
includes a portion of each scan 22, 24, 26, analysis may include creating a
descriptor 34
that describes event 18 through processing the portions. For example, an
algorithm, such as a
subtraction algorithm, may be used to remove or reduce the background that is
common to the
entire volume subset 30 in order to emphasize the event that occurred. This
would then be
25 stored in a database 32 (if present) along with volume sub-set or
"snippet", a term used to
describe a sequence of the sub-volume. In another embodiment, where time is a
difference
between the scans, the volume subset 30 may in a format that allows it to be
replayed as a
video sequence showing the time progression of the event.
30 [0015] The analyzed subset may then be transmitted to a database 32 from
processor 18
to be stored. While database 32 is shown and described, it will be understood
that it may not
be necessary. For example, the analyzed volume may be transmitted directly to
a user
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interface 35, where it is dealt with directly by a user. In addition to its
storage function,
database 32 may also include processing capabilities to either obtain
additional information
from the volume subset, or to analyze large numbers of analyzed subsets to
look for trends,
patterns, etc.
5
[0016] While processor 18 is shown as being a separate element in FIG. 1, it
will be
understood that the processing steps may be divided up among many processor
components.
For example, referring to FIG. 6, processor 18 may be housed within a scanner
housing 50 as
shown, or included in scanner 12 to give it the processing capability to
compare the scans,
identifying events, extracting volume subsets, and transmit the volume subsets
to database 32,
which would then have the processing capability to analyze the volume subset
and the events
they contain.
[0017] In some embodiments, scanner 12 operates multiple sensors 14
simultaneously, or
in parallel, to obtain the scans, while the processor extracts the volume
subsets during the
scanning process. In other words, processor 18 may extract volume subsets
prior to the scans
being completed. For example, if the difference were a difference in time,
each sensor 14
would start scanning prior to the other sensors 14 completing their scan. This
allows a user to
increase the time difference between the scans, which results in detecting
slower moving or
slower occurring events relative to the actual scan rate's time scale.
[0018] In some embodiments, referring to FIG. 2, a display 36 may be connected
to
database 32 and/or processor 18, as the case may be. Display 36 is useful to
draw a user's
attention to a volume subset 30, and to facilitate interaction with the rest
of system 10. If
display 36 is connected after event 28 and subset 30 have been analyzed and
classified, the
user may use an input device 38, such as a computer keyboard, mouse, or data
port for
downloading new instructions or adjusting the existing instructions, to limit
what is displayed
by selecting certain characteristics. For example, a user may select to view
only objects
having certain characteristics travelling at a certain speed in a certain
direction, or if thermal
imaging is used, objects of a certain temperature.
[0019] In some embodiments, the user may also use input device 38, which would
be
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connected to database 32, processor 18, and scanner 12, as the case may be, to
modify various
parameters in system 10. Some examples include the characteristics of the
scans obtained by
scanner 12, the number or frequency of scans, the resolution of the scans, the
predetermined
criteria for identifying events, and the predetermined characteristics used to
classify or
characterize each event by the processor. Input device 38 may also be used to
select an event
stored in the database or displayed on display 36.. This may be done either to
obtain more
information that is stored in the database, to instruct a processor to process
it further to obtain
more information, or, referring to FIG. 4 and 5, to instruct an auxiliary
device 40, which may
be referred to as an analyzer, to obtain more information on the event, such
as by scanning.
This may be done directly, or through database 32. Auxiliary device 40 may be
one or more
geographically dispersed sensors that detect a higher resolution or different
characteristic, or it
may be one or more tracking devices, such as a camera, that is able to follow
the movement of
an event. As the auxiliary device 40 will generally have a narrower field of
view to obtain a
higher resolution, the orientation of auxiliary device 40 is preferably
controlled to be able to
redirect it toward the desired event either automatically, or interactively by
the user.
In another embodiment, the event may be analyzed to characterize it using
projective
geometry, or orthorectification, based on a digital terrain model of the area
in the field of
regard of the scanner and on the three dimensional location and attitude
comprising of three
angles (roll, pitch, yaw) of the principal optical axis of the scanner. For an
object in motion,
this allows the speed, acceleration, heading, location, and size of the object
in motion to be
precisely determined. This information may then be plotted on a display to
provide better
information to a user. Preferably, this would be done once the information has
been stored in
a database by a processor associated with the database. However, it may be
done by any
suitable processor. In the case of a scanner on moving platform such as a UAV,
the precise
timing of the acquisition of each pixel is needed so that an estimate of the 3
dimensional
location of the aircraft is known as well as all the elements relating to the
attitude of the
principal optical axis of the scanner. This information provides through
projective geometry
or photogrammetric methods a registration of each pixel on the digital
elevation model or
virtual digital terrain model. Out of the precise location of two or more
consecutive snippets it
is possible to obtain information relative to speed, heading, acceleration,
size both height
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width and length of a moving object, as well as range and all three geo-
location parameters,
namely: latitude, longitude and altitude. This is more than what a traditional
radar is able to
achieve, hence the name of an Optical Ground Motion Target Indicator is
appropriate for this
invention.
[0020] It will be understood that, generally, the scans obtained by scanner 12
are not
required to be stored once the volume subset has been extracted. However, in
some
circumstances it may be desirable to periodically retain a scan. This may be
done to update
background information that may change over time, or also to compare scans at
a later date to
detect changes over time that may not be rapid enough to be detected by
successive scans in a
scan sequence.
[0021] Example of an Optical System
[0022] An example of an optical system will now be described that may be
employed that
covers the visible up to the far infrared regions of the spectrum (400nm to 12
microns). This
may be for ground based surveillance, or an airborne Optical Ground Motion
Target Indicator
(OGMTI) surveillance system. Other possible uses include a multi-spectral
scanner for the
detection of sea-going vessels, the detection of smoke from a fire, or similar
concepts applied
to other regions of the electromagnetic spectrum including infra-sound, radar
and even x-ray.
The system may also use a combination of these uses.
[0023] Referring to FIG. 4 and 5, the system's general architecture preferably
uses a
close coupling between the scanning system that preferably, but not
necessarily, has a wide
field of regard, and a secondary system, such as one or more analyzers 40. The
role of the
scanning system is the detection, extraction and analysis of an event for
onwards transmission
to the secondary system 40, and includes scanner 12, processor 18, database 32
and/or user
interface 35. The secondary system, or analyzer 40, receives the transmission
either directly,
or through database 32 as shown in FIG. 4 or processor as shown in FIG. 5. The
analyzer 40
has one or more electromagnetic sensors that have a narrower field of regards
than the
scanner 12, and provides a detailed analysis and tracking of the event in
subvolume 30. It is
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controlled by cues provided by the scanning system. At the heart of this
process is the output
from the scanning system which consists of volume subsets, which may also be
referred to as
sub-scenes, sub-sets of data, or snippets, from the main data acquired by
scanner 12. After
scanner 12 has analyzed a plurality these output snippets, they may be stored
in a database 32,
used to trigger on user demand or on pre-defined conditions tracking and
pointing cues to
assist the narrower field of view analyzer system 40 to further documents the
sub-volume of
interest, or both.
[0024] An embodiment of the Optical Ground Motion Target Indicator (OGMTI),
based
scanner surveillance system may have the following features. The principal
embodiment of a
daylight scanner uses tri-linear array of pixels to achieve a real-time
Optical Ground Motion
Target detection. One strategy that may be used to have a complete sequence of
scanned
images is instantaneous detection of motion while scanning occurs. This may
then be
compared for change between the sequence of images. To provide a panoramic 360
degree
total configured scan, multiple scanners, e.g. four, may be provided. In this
example, each
scanner provides a 90 degree segment of the field of regard. In another
embodiment, four
scanners may be employed that use only two sets of linear arrays to cover 360
degrees instead
of four, due to the geometric construct. The typical vertical scan is on the
order of 30 degrees,
but may be adjusted depending on user preferences. For example, if the scanner
provides a 90
degree vertical scan, hemispherical coverage may be provided. The output from
the OGMTI
may be derived in real-time or at a later time from the tri-linear scan.
[0025] Snippets are created, and multiple variables are extracted, such as
eleven or more,
that are related to the targets based on, for example, angular, geographic,
size, speed,
polarization, color, and other measures derived from imagery, time and
spectral
differentiating sources. The snippets are then transferred or transmitted to a
database or to a
processor for the analyzer system, with or without filtering of target data.
Other features may
include:
= Geo-location calculations derived from snippets and other sensors
= Complete server client architecture for the surveillance system
= Algorithms for stabilization, mosaicing and geo-location of data unique to
the
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system
= Scanning and cueing of target may be made within or without the same system
using Analyzer
= Use of multi-spectral differentiation in the analyzer section
= Use of folded mirror optical path for the analyzer and for scanner
= Simultaneous infrared and night vision step-stare scanning and its fusion
into the
architecture
= Simultaneous use of daylight scanning and analyzer with tracking
capabilities
independent of the analyzer
= Filtering ability to display snippets and extraction of historic data based
on geo-
location and characteristic parameters.
[0026] 1. Scanner
[0027] In a preferred embodiment, the scanner surveillance system has a
hardware
portion, a software portion, and a conceptual portion. In the discussion
below, the
embodiment is of a scanner used for volumetric or geographical scanning. It
will be
understood that if the scanner is used in other fields, the examples given may
be modified to
suit the specific purpose.
[0028] 1(a). Hardware platform
[0029] Referring to FIG. 6, the hardware platform 51 has a static or moveable
platform
that supports one or more linear or focal plane array sensors 14 operating in
a defined region
of the electromagnetic spectrum, such as the ultraviolet to the far-infrared
region. These
sensors contain a multiple active sensing elements 52 such as CCD, CMOS, image
intensified
or infrared detectors. There are focal plane image forming optical elements 54
and 56, such
as a lens or catadioptric mirror that are configured for the specific
electromagnetic wavelength
region that is employed. A scanning mechanism 53 is used to translate the
sensors across the
focal plane image formed by the lens or to translate the focal plane across
the sensors I so that
collectively an image is formed. This scanning mechanism may be made up of one
or more
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mirrors, rotating or linear mechanical stages, or combinations thereof. The
scanning
mechanism 53 may be placed before the lens 56 or attached to the sensor 14,
depending on
the mechanism. To control the focus of the image produced by the lens 56 and
its aperture
54, mechanisms that may be electrical, electro-optical or optical in nature
may be used.
5
[0030] The scanning mechanism itself may be scanned by a second scanning
mechanism
55 whose purpose is to provide a plurality of scans that cover a given field
of view up to a
panoramic 360 coverage. Both scanning mechanisms 53 and 55 can be used to
direct the
focal plane image to a specific field of view location both azimuthally and
vertically so that a
10 complete hemispherical coverage is possible.
[0031] One or more processors 18 are used to controls and interacts with the
scanning
mechanisms 53 and 55 in terms of, for example, the speed of the scan, the
limits of scan
coverage, the start and end of scan both horizontally and vertically
(azimuthally), and the
pattern of scan (variable, fixed, reverse, etc.). Other features may also be
used as recognized
by those skilled in the art, depending on the circumstances. The processor 18
may also
control and interact with the acquisition of sensor imagery data produced by
the sensors 14 in
terms of the rate of data acquisition from the sensor, and automatic and/or
manual control of
parameters related to the sensor such as contrast, brightness, gain, etc. The
processor 18 may
also be used to control and interact with the focus and aperture 54 of the
lens 56 through
automatic software algorithms or manual adjustments. The processor 18
preferably controls
communication through a communication link 62 that may be, for example,
wireless, IP
based, LAN, fiber optics or other electronic means to dispatch data. Depending
on the
preferences of the user and the specific application, the transmitted data may
include, for
example, data streams 68 produced by the sensor(s) to a receiving data server
64 for storage,
archival and/or further processing, data from the attitude determination
sensor 58 and GPS
sensor 60, or data including the entire raw or compressed pixel data taken by
the scanning
system to the Data Server 64.
[0032] With respect to the OGMTI, the processor 18 preferably performs OGMTI
detection on two or more images acquired at different times through image
processing
algorithms. The processor 18 would then note rectangular or irregular shaped
areas, known
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as snippets that correspond to the detected images, and transmit them using
the
communications link 62 as described above. In addition, the processor 18 may
create or
define the parameters that are relevant to the motion, including, for example,
(1) dimensions
of the moving object (width, height length, or other size and shape
measurement), (2)
geographic location of the moving object (latitude, longitude and altitude
above sea level for
example), (3) measurements of speed and acceleration of moving object between
each
consecutive and intra-image and combination thereof, (4) heading vector
(azimuth and dip
angles, etc.) of the object between each consecutive and intra-image and
combination thereof,
(5) other derived measures such as slant angle to moving object from the
sensor, slant and
ground range and other derived measures, and/or (6) measurement of derived
pixel luminance
across the operational electromagnetic spectrum in one or more spectral bands.
Optionally,
one or more data servers 64 may also be provided that store data, and
optionally perform
some or all of the functionalities described for the processor 18 above. The
data servers 64
are primarily used to act as the distribution point of the data through IP or
other protocols or
mediums to be shared by any number of user workstations 35 anywhere in the
world, if this
feature is present. Processor 18 or data server 64 may include a compression
hardware chip
66, which may also be an independent component or present as a software
compression
algorithm whose function is to compress data in order to transmit the data
efficiently to or
from the data server 64.
[0033] It will be understood that, in some embodiments, the processing
undertaken by the
processor 18 can also be architecturally configured to be done using the
processing power of
the data server 64.
[0034] The data that is processed by the processor and/or User Workstation(s)
35 that
request and extract data from the Data Server 64 and can through the Data
Server 64 control
the parameters associated with the scanner's operations, filtering and
requesting specific data
from the scanner 12 or the data server 64, and/or a communications link 62
that connects the
processor 18 with the data server 64, and data server 64 with workstations 35.
[0035] The hardware portion of the scanner may also include devices to improve
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calculations of the position of an event. This may include, for example, a tri-
axis gyroscope,
two axis dip meters, or optical flow methods or other means that provides
information to
determine the instantaneous attitude of the sensor unit in order to correct
rotation in any axis
of the scanner and by geometric means that could include a digital elevation
model determine
the geo-location of the target. This may also include a GPS sensor 60 to
assist in precise
timing and geo-location calculations.
[0036] Preferably, a protective scanner housing 50 and associated enclosures,
either
hermetically sealed or otherwise, is provided to protect the various hardware
components
described above.
[0037] 1b. Software portion
[0038] In the geographic application used as.an example herein, the software
portion of a
scanner surveillance system preferably includes software to extract moving
objects from two
or more images acquired at different time intervals. The algorithms for such
software can be
any one of the many available including those that use simple differencing,
those that use
texturing, those that use Multispectral means, etc. At a high level, the
software portion may
also be designed to perform the following functions:
= create OGMTI variables from the snippet imagery;
= determine the geo-location of the mover;
= ortho-rectify the moving object location and other parameters of OGMTI
through
the use of a stored digital elevation model;
= control the sensor parameters and image quality;
= control the aperture and focus;
= receive the GPS and attitude sensor data;
= ensure that sensor is not damaged by illumination of sun or its reflections
on water
and other objects;
= create a virtual Command and Control based on 3-D model of area under
surveillance including digital elevation model data;
= determine scan patterns;
= control communications with Data Server;
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= diagnostic software for the entire system; and
= accessing storage data on the storage medium;
[0039] le. Conceptual portion
[0040] The conceptual portion of a scanner surveillance system is defined to
help in the
design of the hardware and software portions discussed above. Features of the
conceptual
portion may include one or more of the following functions:
= mechanical movements to scan sensor across field of view in any direction
and
scan rate;
= extraction of areas of motion from images created from consecutive scans;
= continuous compression and or streaming of the sub-images to a processor or
Data
Server with and without OGMTI decoded information derived from the extracted
areas of motion;
= external geo-location and attitude information of platform to assist in
determining
OGMTI geo-location, speed and other parameters using digital elevation models
and
orthorectification;
= user or user configured filtering and initiated extraction of data from data
server;
and
= display of data form data server using 3D model of area and symbols.
[0041] In addition to the features described above, an embodiment of a
surveillance
system may also include the ability to simultaneously achieve visible, "night
vision image
intensified and infrared scanning", and narrow field analysis in those same
bands at the same
time using appropriate sensors for the task. There may also be a multi-
spectral camera
addition to the sensors, and a spectrometer to record the spectrum of a target
as seen by the
analyzer. The spectral information may then be used to positively identify the
same target in a
cluttered targets environment. Finally, while the surveillance system as
described is primarily
a passive sensor, there may also be provided a mechanism for illuminating the
target, such as
by laser or other means, including gated imaging concepts, in order to obtain
better imagery,
such as the case in image intensified imagery.
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Advantages:
[0042] The system as describe above permits scanning of wide-volumes
effectively at
the required high resolution. This has traditionally been very difficult to
achieve, as the wider
the field of regards, the poorer is the resolution for a given sensor. The
system can be
designed to handle a large number of discrete events that occur, such as
thousands or more,
and quantify their inherent parameters in a geographic and/or volumetric
context. The data
can then be dispatched to a database, or it can be processed in real-time at
the sensor head.
Those events can then be filtered to focus on a few for increased scrutiny and
analysis. These
filtered events are tracked and higher information content of those events are
provided for
further action in a geographic or volumetric context.
[0043] With these capabilities, it is possible to offer a comprehensive real-
time or at a
later time situation awareness of a volume of space previously unattainable
benefiting a
number of applications including surveillance from the air and ground of large
volume
space.
Variations:
[0044] While the scanner above is described primarily in the volumetric and
geographic
context, it will be understood that many different situations. For example, it
may be used to
analyze a small area or volume where a very high resolution is required.
Events would be
identified, and processed as described above.
[0045] In this patent document, the word "comprising" is used in its non-
limiting sense to
mean that items following the word are included, but items not specifically
mentioned are not
excluded. A reference to an element by the indefinite article "a" does not
exclude the
possibility that more than one of the element is present, unless the context
clearly requires that
there be one and only one of the elements.
[0046] The following claims are to be understood to include what is
specifically
illustrated and described above, what is conceptually equivalent, and what can
be obviously
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substituted. Those skilled in the art will appreciate that various adaptations
and modifications
of the described embodiments can be configured without departing from the
scope of the
claims. The illustrated embodiments have been set forth only as examples and
should not be
taken as limiting the invention. It is to be understood that, within the scope
of the following
5 claims, the invention may be practiced other than as specifically
illustrated and described.
