This invention relates generally to radio-frequency identification (RFID), and more particularly to RFID tag systems.
As defined by the FCC, an ultra-wideband (UWB) signal is an antenna transmission in the range of 3.1 GHz up to 10.6 GHz at a limited transmit power of −41.3 dBm/MHz with an emitted signal bandwidth that exceeds the lesser of 500 MHz or 20% of the center frequency. UWB signals are currently employed for high-bandwidth, short range communications that use high bandwidth radio energy that is pulsed at specific time instants.
Applications for FCC-defined UWB transmissions include distance-based location and tracking applications, and localization techniques that employ precision time-of-arrival measurements. Examples of such UWB applications include radio frequency identification (RFID) tags that employ UWB communication technology for tracking, localization and transmitting information. Other types of UWB applications include precision radar imaging technology. Inventory tracking has been implemented through the use of passive, active and semi-passive RFID devices. These devices have widespread use, and typically respond to interrogation or send data at fixed intervals.
A high density active radio frequency identification (aRFID) environment can easily exceed 1000 aRFID tags for certain application installations, such as cattle feedlot applications where individual cows are each tagged with an aRFID tag. Currently, aRFID installations such as these may be implemented using, a maximum of approximately 1000 aRFID tags per each RFID receiver that is provided for the installation. However, aRFID environments may routinely contain in excess of 40,000 tags within a 1 to 2 sq mile area. One, previous attempt that has been made to reliably receive and process tag data, and to perform geolocation calculations in such environments, is to use software-only coding schemes in order to help distinguish between multiple tags. This method typically works up to the point where available bandwidth is exceeded due to the number of bits being transmitted (−100 bits per tag transmission) and the number of tags in the environment (1000). Existing RFID tag geolocation technologies employ RFID tags which typically report data at a fixed rate, which is acceptable for low tag density environments (i.e., tag density less than approximately 1000) where interleaved and colliding packets are not problematic.
It is known to transmit data from embedded sensors over wired networks or short range wireless links.
Disclosed herein are systems and methods for RFID tag operation. The disclosed systems and methods may be implemented in a variety of applications (e.g., asset or inventory tracking, sensor networks, geolocation devices, etc.) and may be implemented using passive, active and/or semi-passive RFID tag devices that respond to interrogation and/or send data at fixed intervals. Unlike conventional RFID systems, the disclosed systems and methods may be further implemented in one exemplary embodiment using field programmable or re-programmable RFID tag devices that are interactive.
In one exemplary embodiment, the disclosed systems and methods may be implemented to track a wide variety of one or more objects (e.g., for asset or inventory tracking) using a RFID tag device that is capable of changing behavior and/or changing onboard stored tag data based on interactions with tag interface devices such as a remote interrogating unit (e.g., an active RFID interrogator (aRFIDI) system), a handheld unit, a communication bridging device, a local interrogating unit (e.g., an interrogating device that is in relatively close proximity to the RFID tag device as compared to a remote interrogating unit), sensors in close proximity to the RFID tag device, etc. In a further embodiment, the RFID tag device may use FM-based communications (e.g., Narrow Band Frequency Modulation (NBFM)) as a first band for programmability and/or interrogation, and may use UWB-based communications as a second band to report data.
However implemented, each RFID tag device may have a unique identifier that is associated with an object to which it is associated (e.g., attached or otherwise coupled) such that the location of the RFID tag is representative of the location of the object. In this manner, a user or other entity may readily identify the current location of a particular object, based on the location of its associated transmitting RFID tag. Further, the RFID tag device may be configured to be removably associated with an object, e.g., so that the RFID tag device may be associated with a first object and tracked for a period of time with the associated first object, and then removed from association with the first object and then re-associated with a second object and tracked for a period of time with the associated second object, etc. Examples of such first and second objects with which a RFID tag device may removably associated include, but are not limited to, first and second livestock animals (e.g., cows), first and second inventory objects (e.g., shipping boxes or crates), etc.
In one embodiment, a multi-band RFID tag system may be configured as a tag having a first band (e.g., narrow band such as NBFM) transceiver, e.g., for interrogation and/or to allow field programmability of tag behavior and onboard tag data. The first band may be multiple channel-based, meaning that the RF spectrum of the first frequency band is broken up or divided into a plurality of separate channels, and first band communications may be achieved by the RFID tag system between any two devices of the system using a subset of the channels within the first band (e.g., a single one of the channels, two of the channels, etc.) and/or in narrow band fashion by using a sub-set of the channels within the band, e.g., using less than three of the channels. In this way, a first channel of the first band may be used for communication between a first pair of system devices and a second channel of the first band may be used for communication between a second pair of system devices. Such a multi-band RFID tag system may be further configured to have a second band (e.g., wide band such as UWB) transmitter, e.g., for responding to RFID interrogation signals from an interrogator. The second band may be non-channel based, meaning that the RF spectrum of the second frequency band is not broken up or divided up into separate channels, but rather the communication signals are spread across the second frequency band such that the undivided second band may be used by the RFID tag system for all second band communications between devices of the system. One example of a multiple channel-based first band is a NBFM frequency band having a plurality (e.g., 50) channels, and one example of a non channel-based second band is a pulse-based frequency band such as UWB.
The RFID tag system may be configured to collect data from one or more local sensors (e.g., sensors in close proximity to the RFID tag such as positioned on or attached to or located within the object associated with the RFID tag) through the first band link and store data points of interest in onboard storage. The RFID tag system may also be configured to report such collected sensor data to a remote receiver over a second band (e.g., UWB) link and/or to report such collected sensor data to a tag interface device over a first band (e.g, NBFM) link. In high density environments, the RFID tag system may be configured to work in conjunction with a remote interrogating unit. A handheld device (with or without an associated communication bridging device), local interrogating unit or other local tag interface device that is located in close geographical proximity to an aRFID tag (e.g., deployed in the field with the aRFID tag) as compared to the more distant location of a geographically remote receiver may also be additionally or alternatively provided to communicate with such an aRFID tag. In such an embodiment, any of these remote or local tag interface devices may be enabled to retrieve or change data stored on the RFID tag and/or may be enabled to change the operation of the tag. Operations of such a RFID tag that may be changed include, but are not limited to, report rates for tag data, the methodology of interaction of the tag with local sensors, the power levels of the UWB and NBFM devices, etc.
In another embodiment, communication with a multi-band RFID tag device may be established using a third band (e.g., 802.11x WiFi wireless standard such as IEEE 802.11a, b, g, or n) that is different than the first and second bands employed by the multi-band RFID system. Communication between the multi-band RFID tag device and the third band device may be enabled, for example, using a bidirectional communication bridging device that converts first band signals of the RFID tag device to third band signals of another device, and vice-versa. Examples of third band-capable devices that may be bridged for communication with the first band of a RFID tag device include WiFi devices such as smart phone, notebook computer, WLAN router or any other type of WiFi enabled device. In one example, a tag interface control device may be provided in the form of a WiFi-enabled handheld unit (e.g., smart phone) that communicates with a multi-band RFID tag through a bridging device using NBFM radio frequency (RF) communications to retrieve or change stored data and/or change the tag operation (e.g., change programming of the tag). In a further exemplary embodiment, such a WiFi-enabled handheld unit may be configured to be relatively small (e.g., capable of fitting on a person's belt or in a person's pants or shirt pocket), portable, and/or battery or wireless-powered.
In one exemplary embodiment, a RFID tag device may operate most of the time in sleep mode, during which the first band receiving capability of the RFID tag is turned off to save battery life. Such a RFID tag operates in sleep mode for the duration of a sleep cycle which is terminated by a relatively short awake cycle (during which the RFID tag listens for first band signals transmitted by an interrogator system), prior to returning to a sleep cycle. In a further embodiment, communication with such a sleeping RFID tag device may be established from a tag interface device (which may include a communication bridging device) ad hoc and in-between tag awake cycles (i.e., during a tag sleep cycle) by sending a wake-up signal pulse that provides enough energy to activate the circuitry of the sleeping RFID tag device. Alternatively, a tag interface device (including a bridging device) may be configured to continuously send a wake-up message signal for the duration of the default sleep cycle of a RFID tag device to notify any wakened and listening RFID tags in range of the wake up signal that the listening RFID tags should stay active for a longer period of time than the default length of their awake cycle so that the tag interface device may further initiate communications with a specific RFID tag/s.
In another exemplary embodiment, data from one or more embedded sensors may be collected using a first band of a multi-band RFID tag device (e.g., relatively shorter range NBFM communications) and then passed on to a remote receiver from the RFID tag device using a second RF band (e.g., relatively longer range UWB communications). This capability may be employed to allow a first band-equipped RFID tag to collect data from local sensors, and then to report that data over a second band link, allowing the RFID tag device to function as an intermediary bridge device or relay between the sensor/s and a remote receiver. Such a remote receiver may further be in communication with a remote network (e.g., corporate or governmental intranet, Internet, etc.) so that the RFID tag device acts to bridge local sensor data to a remote network, where it may be further processed and/or accessed by one or more users. The RFID tag device may also be interactive in nature, meaning that the tag data storage and/or the tag's operation is reprogrammable in the operational environment. In another exemplary embodiment, collected sensor data may also be passed on to a tag interface device from the RFID tag device using the first RF band (e.g., NBFM communications), for example, allowing a first band-equipped RFID tag to collect data from local sensors, and then to report that data over a first band link to a checkpoint device, handheld device (e.g., through a communication bridging device), interrogator device, etc.
In a further embodiment, a RFID system may be provided that includes one or more RFID tags and an array of embedded sensors that each report data to a receiver in the RFID tag via a first band transmitter included in the sensors. The RFID tag may then report this data to a remote receiver via a second RF band transmitter included in the RFID tag. The collected sensor data may be provided from the remote receiver to a remote network. Advantageously, this system and method for collecting and reporting sensor data may be implemented to collect and report large amounts of data (e.g., greater than about 1 MByte) from embedded sensors. Example applications for collecting and reporting sensor data in the above-described manner include, but are not limited to, asset or inventory tracking where it may be useful to employ embedded sensors placed within objects (e.g., assets, inventory items or livestock) to transmit data about the status/health of the objects (e.g., during shipping or storage) to a remote location and/or to a remote network.
In one respect, disclosed herein is a radio frequency identification (RFID) tag system, including: first band receiver circuitry on a RFID tag for receiving first band radio frequency (RF) signal communications at the RFID tag, the first band being a multiple channel-based frequency band; second band transmitter circuitry on the RFID tag for transmitting second band RF signal communications from the RFID tag, the second band being a non-channel based frequency band; and at least one processing device on the RFID tag that is coupled to the first band receiver circuitry and the second band transmitter circuitry; the at least one processing device being configured to process first band RF signal communications received at the RFID tag by the first band receive circuitry, and to control transmission of second band RF signal communications from the RFID tag by the second band transmitter circuitry. The RFID tag may be configured to remain associated with an object as the object moves from one geographic location to another geographic location.
In another respect, disclosed herein is a method of operating a radio frequency identification (RFID) tag system, including: receiving first band RF signal communications at an RFID tag; processing the received first band RF signal communications on the RFID tag; and transmitting second band RF signal communications from the RFID tag. The first band may be a multiple channel-based frequency band, the second band may be a non-channel based frequency band; and the RFID tag may be configured to remain associated with an object as the object moves from one geographic location to another geographic location.
In another respect, disclosed herein is a RFID communication system, including: a radio frequency identification (RFID) tag configured to receive first band RF signal communications at the RFID tag, process the received first band RF signal communications on the RFID tag, and transmit second band RF signal communications from the RFID tag; and one or more tag interface devices configured to transmit control signals to the RFID tag within the first band RF signal communications, the first band RF control signal communications received at the RFID tag dynamically altering one or more operations of the RFID tag. The first band may be a multiple channel-based frequency band, the second band may be a non-channel based frequency band, and the RFID tag may be configured to remain associated with an object as the object moves from one geographic location to another geographic location.
In one exemplary embodiment, aRFID tag 180 may be configured with the capability to receive NBFM transmissions in one of a plurality of channels of a multiple channel-based frequency band (e.g., one of at least 50 NBFM channels that are randomly distributed among other like aRFID tags 180 with a channel spacing of about 100 KHz). In such an embodiment, each aRFID tag 180 may be originally programmed with one of fifty 900 MHz channels that is selected as that tag's default frequency, so that the manufactured tags are evenly distributed among the 50 available channels. In this regard, 50 channels is the current minimum number of channels required to meet FCC restrictions for a frequency hopping system within the 900 MHZ ISM band (902-928 MHz). Other multiple channel-based frequency based bands may be similarly employed, e.g., with greater or fewer than 50 multiple channels. Example applications of aRFID tags 180 using such multiple channel-based frequency bands may be found further described in concurrently filed U.S. patent application Ser. No. ______, entitled “DATA SEPARATION IN HIGH DENSITY ENVIRONMENTS” by Jonathan E. Brown et al., which is filed on the same date as the present application and which is incorporated herein by reference in its entirety.
Still referring to
In this embodiment, remote interrogator system 190, handheld device 110, and checkpoint system 112 may be further characterized as tag interface control devices which are capable of exerting some control over one or more functions of a RFID tag 180 as described elsewhere herein. Second band receiver 502 operates in this exemplary embodiment to receive signals in a second band from aRFID tag 180, e.g., to receive UWB signals that are an antenna transmission in the range of 3.1 GHz up to 10.6 GHz at a limited transmit power of −41.3 dBm/MHz with an emitted signal bandwidth that exceeds the lesser of 500 MHz or 20% of the center frequency. However, it will be understood that other non-UWB communication signals (e.g., signals of other non-multiple channel-based frequency band) may be employed for second band communication in the practice of the disclosed systems and methods depending on the area of use and/or needs of the given application (e.g., 433 MHz or 915 MHz frequency bands or other suitable band). Moreover, it is also possible that more than two bands may be employed for transmission and/or reception by an RFID tag system 100.
Still referring to
Examples of environments where aRFID communication system 100 may be employed to track and/or obtain information regarding objects contained therein include, but are not limited to, a livestock feed lot, cultivated field, race track, hospital, warehouse, prison, city block, sports stadium, amusement park, airport, train station, shipyard, etc. Examples of objects that may be associated with individual aRFID tags 180 in such environments include, but are not limited to, individual livestock, farm equipment, race cars, hospital patients, warehouse articles/boxes, prisoners, vehicles, sports players or fans, amusement park patrons, baggage and/or passengers, ships or cargo therefore, etc., which may roam throughout the environment. Further information on tracking and monitoring information from aRFID tags in master coverage areas and aggregate coverage areas that include such environments may be found in concurrently filed U.S. patent application Ser. No. ______, entitled “DATA SEPARATION IN HIGH DENSITY ENVIRONMENTS” by Jonathan E. Brown et al., which is filed on the same date as the present application and which is incorporated herein by reference in its entirety.
Still referring to exemplary aRFID communication system 100 of
Still referring to
Still referring to
As further shown in
Data within onboard data storage circuitry 216 may be optionally changed or updated by one or more tag interface devices (e.g., remote interrogator system 190, handheld device 110, bridging device 402, local sensor/s 108, checkpoint system 112, or any other NBFM-transmission capable device). In one exemplary embodiment, the illustrated architecture of aRFID tag 180 may be employed to track a variety of different objects by providing a separate memory map within onboard data storage circuitry 216 of each aRFID tag 180 for each of two or more different types of objects with which the RFID tag 180 may potentially be associated. In this regard, the function of the separate memory map function may be present to provide a separate storage format with data fields appropriate to the given type of object which is currently associated with a given tag, while at the same time providing other separate storage format/s with data fields appropriate to other types of object which may alternately be associated with the given tag (e.g., in the future). This ability to track different types of objects is further supported by the ability to dynamically change operation of an individual aRFID tag 180 on the fly within aRFID communication system 100, e.g., by allowing different data collection rates and/or sensor types which are appropriate for the object associated with a given tag.
Further shown in
Examples of suitable UWB transmitter circuitry and UWB methodology that may be employed for UWB transmissions between aRFID tag 180 and aRFIDI system 190 include, for example, transmitter circuitry described in concurrently filed U.S. patent application Ser. No. ______, entitled “SYSTEMS AND METHODS FOR GENERATING PULSED OUTPUT SIGNALS USING A GATED RF OSCILLATOR CIRCUIT” by Ross A. McClain Jr., et al., and signal transmission systems and methods described in concurrently filed U.S. patent application Ser. No. ______, entitled “PULSE LEVEL INTERLEAVING FOR UWB SYSTEMS,” by Bryan L. Westcott, et al., each of which is filed on the same date as the present application and each of which is incorporated herein by reference in its entirety. Further information on methodology that may be employed for communication using RFID tags 180 may be found in concurrently filed U.S. patent application Ser. No. ______, entitled “MOBILE COMMUNICATION DEVICE AND COMMUNICATION METHOD,” by Bryan L. Westcott et al., which is filed on the same date as the present application and which is incorporated herein by reference in its entirety.
Still referring to
Returning to the exemplary embodiment of
Still referring to
In operation, checkpoint interface control device 112 may be positioned, for example, at a fixed location within a master coverage area 194 of an aRFID system such as described and illustrated in concurrently filed U.S. patent application Ser. No. ______, entitled “DATA SEPARATION IN HIGH DENSITY ENVIRONMENTS” by Jonathan E. Brown et al., which is filed on the same date as the present application and which is incorporated herein by reference in its entirety. In such an application, a checkpoint device 112 may transmit NBFM communications to a given mobile or roaming aRFID tag 180 only when the tag 180 passes within a predefined proximity to the checkpoint device 112 (e.g., within a limited range that is shorter than the allowed roaming distance of the aRFID tag 180 in its deployed RFID tracking environment, and/or that is shorter than the distance to the nearest aRFIDI system 190). Such a proximity-based NBFM transmission from checkpoint device 112 may be implemented within this predefined proximity, for example, by virtue of the checkpoint device 112 sending a first band NBFM broadcast message of defined transmission range out to all tags 180 that come within a given predefined range of the checkpoint device 112. In other cases, a motion detector or other proximity sensor may be employed to trigger a short duration first band NBFM message transmission from the checkpoint device 112 upon detection of a passing object.
These NBFM transmissions from checkpoint device 112 to aRFID tag 180 may be used, for example, to change one or more operations of aRFID tag 180 (e.g., tag data report rate, UWB and or NBFM transmit power levels, methodology of interaction of the tag with local sensors, tag sleep intervals, etc.). Thus, for example, when an object that is associated with a given aRFID tag 180 moves into a given area monitored by a given aRFID system 100, UWB signal transmission rates from the given aRFID tag 180 may be modified, e.g., to an increased frequency.
Thus, in an exemplary cattle sale lot embodiment, frequency of UWB signal transmission intervals may be increased (e.g., from one transmission every eight seconds to one transmission every second) when a particular cow moves from a pre-stage holding area to a televised exhibition area in which potential buyers in the local audience or televised audience need rapid updates to sensed information about the cow and/or its location. Such a change in UWB signal transmission frequency may be effected by placing a first checkpoint device 112 at a point adjacent the entrance (e.g., entrance gate) to the exhibition area so that NBFM command transmissions from the first checkpoint device 112 will be received by any aRFID tag 180 as it passes with its associated cow into the exhibition area to instruct the aRFID tag 180 to increase its UWB signal transmission frequency. A second checkpoint device may be placed at a point adjacent the exit (e.g., exit gate) of the exhibition area so that NBFM command transmissions from the second checkpoint device 112 will be received by any aRFID tag 180 as it passes with its associated cow out of the exhibition area to instruct the aRFID tag 180 to decrease its UWB signal transmission frequency. A similar checkpoint device deployment configuration may be implemented for any tag tracking application where more frequent UWB signal transmissions are desired from an aRFID tag 180 in a given area relative to another given area.
In another example, a checkpoint device 112 positioned near the exit of a given RFID-monitored area or master coverage area may instruct aRFID tags 180 leaving the given monitored area through the exit to cease all UWB signal transmissions. Such an implementation may be desirable, for example, where no RFID tracking is employed outside the given RFID-monitored area and it is desired to conserver power consumption by the tag outside the area. Conversely, a checkpoint device 112 may also be positioned near the entrance a given RFID-monitored area or master coverage area to instruct aRFID tags 180 entering the given monitored area through the entrance to initiate all UWB signal transmissions, e.g., when aRFID tags 180 enter the monitored area in a no UWB transmission state. Alternatively, a single checkpoint device 112 may be positioned at a single access point to a given RFID-monitored area to query the identity of aRFID tags 180 as they pass into or out of the given area, and based on stored information regarding the previous location of each aRFID tag 180 in data storage 316 (e.g., either inside or outside the given monitored area), instruct each aRFID tag 180 to modify its behavior based on whether it is entering or exiting the given monitored area.
It will be understood that a given checkpoint device 112 may operate in similar manner to modify other tag operations (e.g., such as UWB and/or NBFM transmit power levels, methodology of interaction of the tag with local sensors, tag sleep intervals, etc.) when a given aRFID tag 180 passes into or out of a given monitored area. For example, UWB and/or NBFM tag transmit levels may be modified to be higher when an aRFID tag 180 is moving into a larger RFID-monitored area, i.e., where interrogator system/s are spaced farther away and higher-powered UWB transmissions are therefore required.
As shown in
As further shown in
Still referring to
In the exemplary embodiment of
As previously described, an aRFID tag 180 may be configured in certain embodiments to enter a timed and synchronized low power sleep mode to reduce power consumption in-between interrogator polling signals transmitted from an interrogator system 190. In another embodiment, an aRFID tag 180 may be configured to remain in a low power sleep mode at all times except when activated by receipt of external first band signals. In such embodiments, a communication bridging device 402 (or other tag interface device) may be configured to employ one or more techniques for initiating communications with an aRFID tag 180 of the type that is configured to listen for first band transmissions only for short periods of time.
In a first one of such embodiments, an aRFID tag 180 may be provided with an optional RF collection circuit 602 as shown in
In another exemplary embodiment, a communication bridging device 402 (or other type of tag interface device) may be configured to specifically initiate communication with an aRFID tag 180 of the type that operates the majority of the time in a low power sleep mode and only wakes to periodically for short periods of time to listen for interrogator system polling signals (e.g., to listen for 2 milliseconds once every 8 seconds). Such a periodic-waking tag implementation may be employed, for example, to avoid packet collisions in RFID system environments where there are many aRFID tags 180 coexisting in the same RFID system coverage area by programming the tags such that they wake up to listen for NBFM communications in random order and at different times from each other. In such an embodiment, a communication bridging device 402 or other type of tag interface device may be configured to transmit a NBFM signal with a “wake-up” message that instructs any listening aRFID tags 180 to stay active for a longer period of time to allow the tag interface device to initiate further NBFM communications with a specific aRFID tag 180.
The NBFM signal with wake up message may be transmitted continuously for at least the maximum duration of the sleep time of aRFID tag 180. For example, if the aRFID tag 180 is configured to wake up every 8 seconds to listen and then go back to sleep, then the communication bridging device 402 or other type of tag interface device must broadcast its NBFM “wake-up” message continuously for a minimum of 8 seconds to ensure that the aRFID tag 180 receives the wake-up message. In some embodiments, an aRFID tag 180 may be configured so that once it has activated itself it will reenter its sleep mode after the duration of a specific listening time (e.g., after 2 milliseconds in this example). In such cases, the communication bridging device 402 or other type of tag interface device may be configured to transmit its wake-up message within a time period less than or equal to the specific aRFID tag listening time (e.g., within a time period of less than or equal to 2 milliseconds in this example), and to rebroadcast this wakeup message continuously during the duration of the transmitted NBFM signal (e.g., 8 seconds in this example).
Any listening aRFID tags 180 that receive the wake up message will then wake at an increased rate for a given amount of time (e.g., the tag 180 will wake and listen for 2 milliseconds once every 1 second interval for a period of 10 minutes before defaulting back to its once every 8 second wake up period interval). This decreased sleep period is to allow for quicker responses to serial select messages from communication bridging device 402. The communication bridging device 402 may then send a second message which selects a particular aRFID tag 180 based on its serial number. To ensure receipt by the selected aRFID tag 180 this serial select message may be sent continuously for up to the length of the duration of the tag's new wake up period interval (e.g., sent continuously for up to 1 second in the given example). When the particular selected aRFID tag 180 receives this serial select message, it acknowledges receipt to the bridge device 402 and enters a communications state with the bridge device 402. In this state, the selected aRFID tag 180 remains awake until communications are terminated by the bridge device 402 or the loss of a connection between the selected aRFID tag 180 and bridge device 402 is detected. The bridge device 402 may then select another aRFID tag 180 for communication and repeat this process.
In the illustrated embodiment of
Each of local sensors 108a-108n of
Still referring to
In another example, a given sensor 108 may be configured for insertion into a box or other item of inventory 702 that is also associated with a corresponding aRFID tag 180, which may be externally attached to, or internally enclosed within, the same inventory item 702. In such an example, the given sensor 108 may be present alone or with other sensors 108 to monitor the conditions to which the inventory item 702 (or its contents) is exposed. In this regard, each such sensor 108 may include sensing element/s 730 for monitoring and transmitting by NBFM signals to aRFID tag 180 information regarding one or more sensed parameters such as temperature, humidity, vibrational shock, orientational position, etc. Monitoring of such parameters may be desirable where a inventory item 702 includes sensitive contents, such as expensive wines, animals, sensitive electronics, etc.
Whatever the particular application, an individual aRFID tag 180 may receive and store information in tag data storage 216 that has been transmitted by NBFM signal communication from one or more sensors 108, e.g., for later re-transmission by UWB signals from aRFID tag 180 to a UWB remote receiver 502, and/or for later re-transmission by NBFM signals from aRFID tag 180 to a tag interface device such as checkpoint device 112, handheld device 110 (e.g., through a communication bridging device 402) or interrogator device 190. As previously mentioned, a UWB remote receiver 502 may then pass the collected sensor data to a remote network for further processing, storage and/or user access. Additionally or alternatively, aRFID tag 180 may optionally preprocess the collected data (e.g., using tag microcontroller 210) before relaying the pre-processed information to a remote receiver 502 or tag interface device by UWB and/or NBFM signal communication. Examples of such data pre-processing include, but are not limited to, sorting collected data, data averaging, setting alerts for data values outside a given range, recording of maximum and/or minimum data values, selecting particular data for transmission based on data value or other characteristic, organizing data into categories, etc.
It is also possible that aRFID tag 180 may send command signals by first band (e.g., NBFM) signal communications to one or more sensors 108 to alter sensor operation, e.g., such as altering types of sensor data collected, altering method or frequency of sensor data collection, altering sensor data rates or information content transmitted to aRFID tag 180 from sensor 108, etc. Such a command signal may be originated by a processing device on board the aRFID 180, or may be received from a tag interface device and stored in onboard data storage of aRFID tag 180, for relay and later retransmission to one or more sensors 108 that are out of first band signal communication range with the tag interface device.
Optional storage of collected sensor information in data storage 216 of aRFID tag 180 may be useful, for example, where an object 702 resides (e.g., is stored or transported) for a period of time during which no access exists for transmission of sensor data to a UWB receiver (e.g., goods or livestock shipped from one location to another, goods stored in a warehouse, livestock allowed to graze in an uncontrolled area, etc.). Upon arrival at a location in signal communication proximity to an active aRFIDI system 190 and UWB receiver 502, the aRFID tag 180 may receive a NBFM interrogator polling signal from the aRFIDI system 190 and transmit a UWB response signal in response thereto. The UWB response signal may include stored historical sensor information that has been collected by aRFID tag 180 from associated sensors 108 during the period of time that no access was available for transmitting sensor information. The transmitted historical sensor information may then be reviewed to determine, for example, what conditions an object 702 has been exposed to during transit or storage. Where a tagged object is livestock or other animal, the transmitted historical sensor information may also or alternatively include monitored health information (e.g., body temperature, vital signs, etc.) that may be reviewed to determine the health history of the animal during transit, storage, grazing, etc.
Although
In one example implementation of the preceding tag relay embodiment, a sensor 108 may be deployed in a location that is out of signal communication range with any aRFIDI system 190 and UWB receiver 502. Such a location may be, for example, a remote area of a cattle ranch, and such a sensor 108 may be configured with a sensor element that measures, for example, environmental conditions such as rainfall or water trough level. One or more multiband aRFID relay tags 180 may be associated with livestock animals that roam the ranch between the remote area of the ranch and another area of the ranch that is within signal communication range of an aRFIDI system 190 and UWB receiver 502. Sensor information from the remotely-located sensor may be downloaded and stored by a given aRFID relay tag 180 when its associated livestock animal passes within NBFM signal communication proximity to the remotely-located sensor 108. The aRFID relay tag 180 may then relay and transmit the stored sensor information to the UWB receiver 502 when the livestock animal returns to within signal communication range of aRFIDI system 190 and UWB receiver 502.
In another tag relay embodiment example, one or more sensors 108 may be associated with a first animal (wild animal or livestock) by attachment or insertion, and the first animal released, e.g., to the wild. An aRFID relay tag 180 may be associated with a second animal that is also released to freely associate with the first animal, but that is also trained to return to within signal communication range of an aRFIDI system 190 and a UWB receiver 502. Each time the second animal associates with (i.e., comes in close proximity to) the first animal, the aRFID relay tag 180 collects sensor information from sensor 108 that is associated with the first animal and stores this information in its data storage 216. The stored sensor information is then relayed and transmitted from the aRFID relay tag 180 to the UWB receiver 502 when the second animal returns to within signal communication range of the aRFIDI system 190 and UWB receiver 502. The second animal may be released and returned over and over in this manner to monitor health, location, or other aspects of the first animal over time.
It will be understood that one or more of the tasks, functions, or methodologies described herein may be implemented, for example, as firmware or other computer program of instructions embodied in a tangible computer readable medium that is executed by a CPU, microcontroller, or other suitable processing device.
While the invention may be adaptable to various modifications and alternative forms, specific embodiments have been shown by way of example and described herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. Moreover, the different aspects of the disclosed systems and methods may be utilized in various combinations and/or independently. Thus the invention is not limited to only those combinations shown herein, but rather may include other combinations.