Abstract:
A field data collection and relay station is equipped to receive sensor data from locations in a region. The station has directional antennas that are focused to transmit and receive energy in and from unique directions. The station establishes a wireless network in which the sensor data is formatted and distributed to one or more of the directional antennas. As a result, the sensor data is wirelessly transmitted in at least one unique direction.

Description:
ORIGIN OF THE INVENTION 
     The invention described herein was made in the performance of official duties by employees of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to remote and unmanned data collection systems, and more particularly to a data collection and relay station that collects data from a variety of field sensors and relays the data wirelessly in specific direction(s) for pickup and re-transmission by other such stations whereby the totality of the stations define a network. 
     BACKGROUND OF THE INVENTION 
     Surveillance of a large area is typically carried out by aircraft flyovers and/or manned reconnaissance. However, this type of surveillance is costly, is not continuous, and can be dangerous when the area is either occupied by hostile forces or is environmentally hostile due to the presence of chemical, radiological or biological agents. Accordingly, it would be preferable for field surveillance to be carried out in an unmanned fashion by various “sensors” (e.g., cameras, acoustic sensors, temperature sensors, chemical/radiological/biological sensors, etc.) that can be placed/located in a field location. 
     In general, most situations will require a variety of different types of sensors in order to generate sufficient data for performance of complete surveillance. However, different types of sensors very often generate different data formats and protocols. Further, when a surveillance area is large, data collection issues arise when sensor cabling is required as such cabling becomes difficult or impossible. Even if a sensor is equipped with wireless transmission capabilities, transmission distances are relatively short (e.g., typically on the order of 1000-2000 feet) thereby rendering them useless when a large area must be reconnoitered. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide an unmanned data collection and relay station. 
     Another object of the present invention is to provide a system that can collect data in a wireless fashion and re-transmit the data in a wireless and directive fashion. 
     Still another object of the present invention is to provide a data collection and relay station that can function as a node in a wirelessly coupled network of such stations. 
     Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings. 
     In accordance with the present invention, a field data collection and relay station has an omni-directional antenna for receiving sensor data transmitted wirelessly from a location lying within a region approximately centered on the omni-directional antenna. The station also has directional antennas, each of which is focused to transmit/receive energy in/from a unique direction. A wireless network establishment means is coupled between the omni-directional antenna and the directional antennas for standardizing formats and protocol of the sensor data and for distributing the sensor data so standardized to at least one of the directional antennas. As a result, the sensor data is wirelessly transmitted in at least one unique direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects, features and advantages of the present invention will become apparent upon reference to the following description of the preferred embodiments and to the drawings, wherein corresponding reference characters indicate corresponding parts throughout the several views of the drawings and wherein: 
         FIG. 1  is a block diagram of a field data collection and relay station in accordance with a first embodiment of the present invention; and 
         FIG. 2  is a block diagram of a second embodiment of a field data collection and relay station equipped to also receive a variety of sensory input signals in a hardwire fashion. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to  FIG. 1 , a block diagram of a field data collection and relay station is referenced generally by numeral  10 . Data collection and relay station  10  is assumed to be placed in a field location where a number of sensors  100  have been placed. Sensors  100  can be the same type or different types depending on the application. For example, the sensors can be active or passive acoustic, vibration, temperature, chemical radiological, biological, etc., sensors without departing from the scope of the present invention. Each of sensors  100  is assumed to have the capability to wirelessly transmit its collected data. For example, each of sensors  100  can be “packaged” with or incorporate a wireless client adapter card (not shown) that formats data for wireless data transmission as is known in the art. Station  10  is equipped to collect the transmitted sensor data for all of sensors  100  within a radius of sensitivity of station  10 . 
     Station  10  has an omni-directional antenna  12  for receiving data transmissions for each of sensors  100  that reside in a substantially circular region centered on antenna  12  and defined by dashed line  50 . The radial size of region  50  is determined by local terrain and/or obstructions, but extend to radii on the order of one thousand feet. Coupled to antenna  12  is an access point device  14  that provides an entry point onto a wireless network for the data collected and transmitted by sensors  100 . Access point  14  can be any device capable of performing the above-described function. By way of example, access point  14  can be a series  350  access point available from Cisco Systems. 
     Coupled to access point  14  is a switch processor  16  (e.g., an ethernet switch) that controls distribution of the sensor data received from access point  14 . As used herein, distribution refers to the delivery of a particular sensor&#39;s data to one or more of station  10 &#39;s wireless bridge  18  and corresponding directional antenna  20  combinations. Typically, each wireless bridge  18  is selected for compatibility with access point  14 . Accordingly, by way of example, each wireless bridge  18  could be a series  350  wireless bridge available from Cisco Systems. 
     In general, each wireless bridge/directional antenna combination provides the means to wirelessly link station  10  with either another similar data collection and relay station (not shown) or a command center (not shown) on the wireless network to which station  10  belongs. More specifically, each wireless bridge/directional antenna combination is configured to transmit sensor data provided thereto (by switch processor  16 ) in a predetermined (i.e., preprogrammed) specified direction with each antenna  20  configured to focus its transmitted energy  22  in a unique direction. In this way, the various sensor data can be relayed in specific directions for further relaying or for ultimate use by a specific end user. 
     In cases where station  10  will be used to relay data, each one of antennas  20  that will serve as an intermediate relay point must also be able to receive wireless transmissions from a unique direction. Each such received wireless relay will then be distributed and re-transmitted by that particular station as controlled by that station&#39;s switch processor. To avoid cross-talk and/or data overlap, each wireless bridge/antenna combination can be programmed to transmit on a unique and non-overlapping frequency or channel. The number of bridge/antenna combinations utilized by station  10  can be varied based on the application and is, therefore, not a limitation of the present invention. 
     While station  10  is contemplated for use with sensors  100  that are equipped for wireless transmission, the present invention is not so limited. For example,  FIG. 2  illustrates another embodiment of the data collection and relay station of the present invention that is referenced generally by numeral  30 . Station  30  includes all of the elements of station  10  and further includes the capability to receive “sensor” data for sensors that are hardwired into station  30 . For example, if video surveillance of some or all of region  50  is required, a video camera  102  could be hardwired into a video processor  32  that converts standard analog video signals (e.g., NTSC video signals) into a digital format suitable for efficient wireless transmission. One such digital format is the well known motion JPEG video stream or MJPEG. Video processor  32  is part of station  30  and is hardwired into switch processor  16 . The video data can be distributed to the appropriate one(s) of the wireless bridge/directional antenna combinations by switch processor  16  as previously described. 
     Since it is also possible that station  30  may need to collect sensor data from other types of cabled sensors, switch processor  16  can have one or more ports  16 A and  16 B provided thereon for receiving various types of hardwire inputs. For example, port  16 A is representative of one or more serial interface ports (e.g., RS232, RS422, etc.) and port  16 B is representative of one or more ethernet interface ports (e.g., RJ-45 ethernet port) that allow station  30  to receive sensor inputs from sensors (not shown) that do not support any wireless interconnectivity. Once again, any hardwired sensor data received by switch processor  16  can be distributed to the appropriate one(s) of the wireless bridge/directional antenna combinations by switch processor  16  as previously described. 
     The advantages of the present invention are numerous. The data collection and relay station provides the hardware capability for the establishment of a wireless network in an area of surveillance. Once it is established, all “sensors” coupled to the station will have their data transmitted/relayed wirelessly to one or more stations on the network until the sensor data reaches its ultimate destination. The size of the surveillance area can be expanded merely by adding additional sensors and accompanying data collection and relay stations. Once an area is set up, surveillance can continue for an extended period of time without any manned intervention as data collection, distribution and relay is handled in a predetermined fashion as dictated by each station&#39;s switch processor. 
     Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light of the above teachings. For example, each station could be equipped to receive programming instructions via its omni-directional or directional antennas so that the on-board switch processor and/or wireless bridges could be reprogrammed from a remote location. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described.