Patent Application
20080026713
A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in conjunction with the following figures, wherein like reference numbers refer to similar elements throughout the figures.
The following detailed description is merely illustrative in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any express or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
The invention may be described herein in terms of functional and/or logical block components and various processing steps. It should be appreciated that such block components may be realized by any number of hardware, software, and/or firmware components configured to perform the specified functions. For example, an embodiment of the invention may employ various integrated circuit components, e.g., radio-frequency (RF) devices, memory elements, digital signal processing elements, logic elements, look-up tables, or the like, which may carry out a variety of functions under the control of one or more microprocessors or other control devices. In addition, those skilled in the art will appreciate that the present invention may be practiced in conjunction with any number of data transmission protocols and that the system described herein is merely one exemplary application for the invention.
For the sake of brevity, conventional techniques related to signal processing, data transmission, signaling, network control, the 802.11 family of specifications, and other functional aspects of the system (and the individual operating components of the system) may not be described in detail herein. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent example functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical embodiment.
In general, one or more imaging devices are incorporated into various WLAN components, and are configured to work in conjunction with software modules within the imaging device or otherwise distributed throughout the network to provide surveillance, asset tracking, and the like.
Without loss of generality, in the illustrated embodiment, many of the functions usually provided by a traditional access point (e.g., network management, wireless configuration, and the like) are concentrated in a corresponding wireless switch. It will be appreciated that the present invention is not so limited, and that the methods and systems described herein may be used in conjunction with traditional access points or any other device that communicates via multiple RF channels.
Referring to
A particular AP 120 may have a number of associated MUs 130. For example, in the illustrated topology, MUs 130(a), 130(b), and 130(c) are associated with AP 120(a), while MU 130(e) is associated with AP 120(c). Furthermore, one or more APs 120 may be connected to a single switch 110. Thus, as illustrated, AP 120(a) and AP 120(b) are connected to WS 110(a), and AP 120(c) is connected to WS 110(b).
Each WS 110 determines the destination of packets it receives over network 104 and routes that packet to the appropriate AP 120 if the destination is an MU 130 with which the AP is associated. Each WS 110 therefore maintains a routing list of MUs 130 and their associated APs 130. These lists are generated using a suitable packet handling process as is known in the art. Thus, each AP 120 acts primarily as a conduit, sending/receiving RF transmissions via MUs 130, and sending/receiving packets via a network protocol with WS 110.
AP 120 is typically capable of communicating with one or more MUs 130 through multiple RF channels. This distribution of channels varies greatly by device, as well as country of operation. For example, in one U.S. embodiment (in accordance with 802.11(b)) there are fourteen overlapping, staggered channels, each centered 5 MHz apart in the RF band.
As mentioned briefly above, one or more imaging devices 140 are connected to the network to provide wireless surveillance. In this regard, the various tasks described below in connection with imaging devices 140 may be performed by software, hardware, firmware, or any combination thereof, and may be located in the AP, the MU, the WS, a computer system connected to network 104, or any combination thereof.
Imaging device (or simply “ID”) 140 may include any combination of hardware/software/firmware, image processing systems, etc. capable of capturing some form of image (e.g., a digital image) of the environment within its field of view. Imaging device may therefore be an optical device (video camera), a thermal (infrared) imager, or any other imaging device now known or developed in the future.
In one embodiment, imaging device 140 is connected (e.g., through a wired connection) to an AP 120. Imaging device 140(a) in
In an alternate embodiment, imaging device 140 is connected to an MU. As illustrated in
In yet another embodiment, imaging device 140 itself functions as an MU. Imaging device 140(c) in
As shown, an entity (e.g., an individual, asset, etc.) 210 may be present within field of view 202(a) of ID 140(a) initially, and then be relocated to within field of view 202(b) of ID 140(b). That is, ID 140(a) will produce an image of entity 210, process the image, then transmit over the network (not shown) through the WLAN device to which it is connected. In the interest of simplicity, the various MUs and APs that are connected to or otherwise communicate with IDs 140(a) and 140(b) are not shown in
The position and orientation of the various IDs 140 may be known a priori (i.e., through a fixed installation position) or determined through any convenient means, for example, through the use of RFIDs, GPS, triangulation, analysis of their respective images, or the like. In the case where an ID 140 is directly incorporated into or attached to the housing of an MU or AP, the location of the ID 140 will be known to the extent that the attached MU or AP is also known.
As mentioned above, images produced by IDs 140 may be processed using one or more image processing algorithms known in the art, and may be analyzed to accomplish feature recognition, object identification, or the like. The image processing may be performed by the ID itself, the WLAN component to which it is connected, the WS, or another computer accessible over the network—for example, a central security station or the like. In general, a computer-implemented subsystem comprising any number of components may be used.
Using known image processing techniques, for example, IDs may be used to track an entity as it moves through the environment. When an entity is recognized, an object identifier may be assigned from a database, and its location noted. In the event that the entity is moving outside of or within a predetermined region, an alarm may produced to indicate that the movement has occurred.
It should also be appreciated that the example embodiment or embodiments described herein are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing the described embodiment or embodiments. It should be understood that various changes can be made in the function and arrangement of elements without departing from the scope of the invention as set forth in the appended claims and the legal equivalents thereof.
