Abstract:
In a method for controlling pricing of a product, a radio frequency identification (RFID) tag having at least one processor is attached to a monitored product. A value indicative of a degree of exposure to an environmental condition is obtained. The obtained value is compared with a predetermined value range. A price of the monitored product is adjusted when the result of the comparison falls outside the predetermined value range.

Description:
TECHNICAL FIELD 
     The present invention relates generally to RFID tags and more specifically to RFID tags having one or more environmental sensors. 
     BACKGROUND 
     Active RFID tags are well known today. For example, the Matrics Group manufactures “MicroSensys™” Active RFID tags, and KSW Microtec manufactures “Smart Active Label™” Active RFID tags. An active RFID tag includes a small battery, and transmits RF signals via an integral antenna. The battery adds significant cost to the RFID tag. The RFID may be preprogrammed with information that represents, for example, the identity of the product which bears the RFID tag. The transmitted RF signals typically include the identity of the active RFID tag. If the active RFID tag includes additional data, the active RFID tag may transmit the data as well. An active RFID tag can effectively transmit to a receiver up to 100 meters away. 
     Passive RFID tags are also well known today. A passive RFID tag does not include a battery; instead, the passive RFID tag has an integral antenna which receives RF signals from an active RFID tag or remote transceiver. The transmitted RF signals power the passive RFID tag, i.e. the passive RFID tag captures the energy of the RF signals which it receives and uses the energy to drive transceiver and other circuitry on the passive RFID tag. The transceiver circuitry on the passive RFID tag transmits information, such as the identity coded into the passive RFID to identify the product which bears the passive RFID tag. The passive RFID tag may also include a memory to store any type of information transmitted by the active RFID tag or other remote transceiver. Typically, passive RFID tags have a range of about three meters. 
     It was also known for an active or passive RFID tag to include an environmental sensor, such as a temperature or humidity sensor. For example, the Matrics Group MicroSensys™ active RFID tags and KSW Microtec Smart Active Label™ active RFID tags include temperature sensors. The temperature sensor measures the ambient temperature, and circuitry on the RFID tag containing the sensor records information about the temperature. For example, if the RFID tag is attached to a temperature sensitive product such as a food package, the RFID tag will record whether the food was exposed to excessively hot or cold temperatures during shipment. The active RFID tag may also periodically record temperature samples over time. 
     SUMMARY 
     In one aspect, a method for controlling pricing of a product is provided. The method comprises attaching a radio frequency identification (RFID) tag having at least one processor to a monitored product. The method further comprises obtaining a value indicative of a degree of exposure to an environmental condition. The method further comprises comparing the obtained value with a predetermined value range. The method further comprises adjusting a price of the monitored product when the result of the comparison falls outside the predetermined value range. 
     In another aspect, a computer program product for controlling pricing of a product using a radio frequency identification (RFID) tag attached to a monitored product is provided. The computer program product comprises one or more computer-readable tangible storage devices and program instructions stored on at least one of the one or more computer-readable tangible storage devices. The program instructions are executable by the RFID tag. The program instructions comprise program instructions to measure a value indicative of a degree of exposure to an environmental condition. The program instructions further comprise program instructions to compare the measured value with a predetermined value range. The program instructions further comprise program instructions to adjust a price of the monitored product when the result of the comparison falls outside the predetermined value range. 
     In another aspect, a computer system for controlling pricing of a monitored product using a radio frequency identification (RFID) tag attached to the monitored product is provided. The computer system comprises RFID tag having one or more processors, one or more computer-readable memories, one or more computer-readable tangible storage devices, and program instructions stored on at least one of the one or more storage devices for execution by at least one of the one or more processors via at least one of the one or more memories. The program instructions comprise program instructions to measure a value indicative of a degree of exposure to an environmental condition. The program instructions further comprise program instructions to compare the measured value with a predetermined value range. The program instructions further comprise program instructions to adjust a price of the monitored product when the result of the comparison falls outside the predetermined value range. 
     In yet another aspect, a method for adjusting certified potency of a product is provided. The method comprises attaching a radio frequency identification (RFID) tag having at least one processor to a monitored product. The method further comprises obtaining a value indicative of a degree of exposure to an environmental condition. The method further comprises comparing the obtained value with a predetermined value range. The method further comprises adjusting a certified potency of the monitored product when the result of the comparison falls outside the predetermined value range. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a pictorial representation of a product delivery system that employs environmental sensor technology to measure monitored product environment data in accordance with an embodiment of the present invention. 
         FIG. 2  is a block diagram of an active RFID tag with an environment sensor physically attached to a monitored in accordance with an embodiment of the present invention. 
         FIG. 3  is a block diagram of a passive RFID tag with an environment sensor physically attached to a monitored product in accordance with another embodiment of the present invention. 
         FIG. 4  is a flowchart of the operation of an RF encoding program embedded within an active RFID tag of  FIG. 2  and/or a passive RFID tag of  FIG. 3  in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     An embodiment of the present invention provides means for automatically adjusting a price of a product when the product has been exposed to adverse environmental conditions for a predetermined period of time. Embodiments described herein will have numerous applications; however, at least some embodiments will be particularly useful in relation to packaged food products including dairy products such as milk. 
     Milk is commonly sold in cardboard cartons and safe handling practices, as well as Government regulations, require that such products not be exposed to temperatures above a predetermined level for a set length of time. In the case of milk, the product should not be exposed to temperatures above 5° C. for more than 15 minutes. The industry meets these requirements by ensuring that such products are always stored or kept in adequate refrigerated conditions. However, this is not always possible, particularly during transport and delivery of such products. Accordingly, despite best endeavors, it is still possible for such products to be exposed to elevated temperatures well beyond stipulated time even though the conditions of transport and storage meet the legal requirements. 
     Accordingly, an embodiment of the present invention provides means to measure environmental conditions, to detect departure from allowable limits, and to automatically adjust purchase prices of retail products when such products have been subject to adverse environmental conditions for a time that is greater than allowable. Alternatively, such products may be flagged as unacceptable for sale, based on criteria provided by a supplier. 
     Another embodiment of the present invention provides means for automatically indicating a relative and/or remaining potency of a product, such as chemical and pharmaceutical products, when the product has been exposed to adverse environmental conditions that might degrade the quality of the product. For example, hydrogen peroxide is a widely used oxidant. Although concentrated solutions of hydrogen peroxide are stable, diluted hydrogen peroxide solutions with even trace level of impurities present tend to degrade significantly during storage or use. Possible causes of the degradation include exposure to heat and radiation. Such adverse environmental conditions can render the solutions unstable resulting in the decomposition of the hydrogen peroxide into water and oxygen during transportation or storage. Accordingly, an embodiment of the present invention provides means to certify potency of the product based on observed environmental conditions. 
     With reference to  FIG. 1 , an illustrative diagram of a product delivery environment is provided in which illustrative embodiments may be implemented. It should be appreciated that  FIG. 1  is only provided as an illustration of one implementation and is not intended to imply any limitation with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environments may be made. Like numbers refer to like elements throughout. The embodiments described herein provide means for measuring the environmental conditions to which a monitored product has been subjected during its movement through a supply chain and provide means for adjusting a purchase price of the monitored product based on a degree of exposure to the environmental condition. 
     The term “container” will be used herein to refer to virtually any object that can be used to enclose or hold a product, such as, for example, but not limited to, an envelope, packet, mailing tube, bag, box, package, can, bucket, crate, palate, shipping container, and the like. 
       FIG. 1  is a pictorial representation of a product delivery system  100  that employs environmental sensor technology to measure monitored product environment data in accordance with an embodiment of the present invention. The product delivery system  100  includes an RFID tag  105  physically attached to a product in a container  101  that is to be shipped from, for example, a manufacturer of the product to a receiver. As referred to herein, an RFID tag is an automated data collection device having an integrated environmental sensor. As is known in the art, RFID technology provides a wireless means of automated data collection that eliminates the need for a direct line of sight between a data reader and the RFID tag. This allows the RFID tag  105  to be placed anywhere on or in the monitored product or the container  101 . In other words, the RFID tag  105  can be placed inside the container  101 , it can be affixed to an outer surface of the container  101  (as shown in  FIG. 1 ), or it can be positioned directly on the product that is inside the container  101 , for example. An RFID tag  105  can be an active RFID tag  200 , described below in conjunction with  FIG. 2  or passive RFID tag  300  depending on whether they have an on-board power source or not. The environmental sensor portion  222  of the RFID tag  105  is described further below in conjunction with  FIGS. 2 and 3 . 
     In one embodiment, product environment data measurements can be collected by the RFID tag  105  that is physically associated with a monitored product at one or more points along the shipping route. For example, the RFID tag  105  may be attached to the monitored product when it is placed in a container or package  101  for shipment. In this illustrative embodiment, the RFID tag  105  may also be used for keeping track of inventory and other functions related to product delivery. 
     According to another embodiment of the invention, the RFID tag  105  may be fixed to components or products for keeping track of environmental conditions during manufacturing process and/or post-manufacturing functions. In this embodiment the post-manufacturing use of the RFID tag  105  can also relate to specific information carried by the tag, such as lot number, expiration date, and calibration. 
     Calibration may be important for a number of products that inevitably vary somewhat during manufacturing and/or movement through a supply chain (delivery system), and thus need a calibration number for proper use by the customer. One example is electronic components; another is dry reagent testing strips (such as glucose test strips), which have variation and need to carry a calibration indication. The calibration number or code (which can be encoded in the RFID tag  105 ) may enable a reader to determine the specific characteristics of the test strip, as well as where the strip came from, the expiration date of the strip, whether this is the correct strip for the test to be conducted, and the like. This information may be important for accuracy and automatic calibration in post-manufacturing use. The objective of attaching the RFID tag  105  is that the dry reagent test strip carries all critical information directly on the strip, to enable automatic calibration, tracking, checking and tracing of these strips, thus eliminating human error. The same tag, pursuant to an embodiment of the present invention, can be used for tracking environmental conditions during the manufacturing process, to be sure that each strip has not been exposed to environmental conditions that might have affected its potency/purity. It is thus among the objects of various embodiments of the present invention to provide and establish RFID tag  105  that is embedded in or carried on products or components, and the RFID tag  105  carries critical environmental condition measurements as the product progresses in the manufacturing procedure and/or progresses through the shipping route. 
     Referring back to an embodiment illustrating the product delivery system  100 , when the RFID tag  105  is attached to the container  101 , a first environmental condition measurement (baseline) can be made and stored in the RFID tag  105  along with other information, such as calibration data. Additional environmental condition measurements can be made during various transit points  108 . For example, if the monitored product is stored in a warehouse before delivery, one or more environmental condition measurements may be obtained while the product is stored in the warehouse  110 . 
     Once a designated delivery location is identified, a monitored product to be shipped may be moved to a designated place for pickup  112  by a carrier for delivery to receiver. A delivery vehicle may then transport the container  101  and product therein to the receiver&#39;s location  114  to complete delivery of the product in its container. The receiver can then open the container, retrieve the product and subsequently sell it to the end user of the monitored product. Alternatively, prior to the final delivery, the container  101  with the product can be transported via aircraft, train, and the like to a hub near the receiver&#39;s location. As the product in the container  101  is transported and stored from the packaging location  106  to the point of sale location  116 , the environmental sensors integrated with the RFID tag  105  may collect environmental data describing one or more environmental conditions to which the monitored product has been subjected prior to sale. 
     The type of environmental data obtained from the environmental sensor integrated with the RFID tag  105  may depend on the type of sensor used. Preferably, the environmental sensor described herein may be capable of sensing one or more environmental conditions such as gamma radiation, x-ray radiation, extreme temperature, smoke plume, pressure, vacuum, vibration, shock, humidity, moisture, light, air, and the presence or absence of a particular chemical. In one embodiment, the RFID tag  105  is operable to generate and store time data in association with product environment data for indicating the time of sensing the environment condition associated with the container  101  and the product contained therein. 
     In one embodiment, the environmental data may be read wirelessly when the RFID tag comes within range of an RFID interrogating device, such as a cash register equipped with RFID technology (i.e. RFID reader). In another embodiment, the environmental data may be read by an RFID reader at a chemical plant, for example, to determine remaining potency of the product in order to select an appropriate product delivery or storage method to prevent further degradation of the product. 
     In other words, the RFID tag having an environmental sensor can be used to record historical data of the environmental conditions that a product and/or container  101  is exposed to during transport, manufacturing, storage, and the like. This capability to verify that one or more environmental conditions have been maintained during manufacturing, storage, and transport can be important when shipping a variety of products that require special handling. A few examples of products that may require special handling because of their sensitivity to temperature, pressure, light, moisture, radiation and/or other environmental conditions include pharmaceuticals, biological tissue, perishable foods, and the like. 
     As mentioned above, a record of the environmental conditions to which a monitored product has been subjected during shipment and storage or during manufacturing process can be obtained by the RFID tag  105  that may sense the environmental condition periodically or otherwise along its route and may store sensed product environment data for later analysis. It should be noted that if the RFID tag is implemented as a passive RFID tag  300 , it may log excursions above and/or below predetermined environmental condition thresholds. Alternatively, if periodic sampling of environmental conditions is important, the RFID tag  105  may be implemented as an active RFID tag  200 . 
     How frequently the environmental sensor should sample and store measurements can be determined in a variety of ways and is an implementation decision. In general, the sampling period of the environmental sensor should be less than the time required for the monitored product to spoil when exposed to the environmental condition. Thus, for example, if the monitored product will be spoiled by exposure to an unacceptable environmental condition for a few seconds, then the environmental sensor should be capable of taking environment condition measurements at least every second or less. Similarly, if the monitored product will spoil if exposed to an unacceptable environmental condition continuously over several hours, then the environmental sensor can take product environmental data readings on an hourly basis, for example. 
     Spoilage of a product can also depend not only on the time for which the product has been exposed to an unacceptable environmental condition, but also upon the severity level of the environmental condition. Hence, in some embodiments of the present invention, the RFID tag  105  may be configured to take environmental condition measurements more frequently if an environmental condition is relatively severe, and less frequently if the environmental condition to which the product is exposed is less severe. By storing the product environmental data readings in correspondence with the time at which such readings were taken, the active RFID tag, such as tag  200 , may use this historical information to adjust a purchase price of the monitored product at the point of sale  116  based on the duration and/or the severity level of the environmental condition to which the monitored product has been exposed, as described below in conjunction with  FIG. 4 . In another embodiment, the environmental data may be analyzed to determine and report the remaining potency level of the monitored product when the RFID tag comes within range of an RFID interrogating device (i.e. RFID reader) in a manufacturing environment. 
     In various embodiments of the present invention, the RFID tag  105  may represent an active RFID tag.  FIG. 2  is a block diagram of an active RFID tag with an environment sensor which may be physically attached to a monitored product, in accordance with an embodiment of the present invention. Active RFID tag  102  may include known type of environmental sensor  222 . Preferably, the environmental sensor described herein may be capable of sensing one or more environmental conditions such as gamma radiation, x-ray radiation, extreme temperature, smoke plume, pressure, vacuum, vibration, shock, humidity, moisture, light, air, and the presence or absence of a particular chemical. 
     In accordance with an embodiment of the present invention, the active RFID tag  200  may further include power source  204  (such as a Lithium-Ion battery), electronic transceiver circuitry  208 , antenna  210 , integrated circuit CPU  212 , and memory  214  (such as EEPROM or SRAM). The active RFID tag  200  may also include electronic control circuitry  218  and RF encoding program  216  in memory  214 , according to an embodiment of the present invention. The transceiver  208  may include a transmitter and a receiver coupled to the antenna  210  to transmit and receive RF signals. In an embodiment, the control circuitry  218  may be coupled to the environmental sensor  222  and may provide information regarding measured environmental conditions to the CPU  212  for storage in the memory  214 . For example, the control circuitry  218  may periodically monitor the environmental sensor  222 , compare the monitored environmental condition samples to predetermined upper and lower threshold limits, and report to the CPU  212  if and when the sensed environmental measurement is, for example, above the upper limit or below the lower limit. 
     According to an embodiment of the present invention, the RF encoding program  216  may execute on the CPU  212  to adjust a price of the monitored product, for example, based on the historical environmental information stored in the memory  214  and to broadcast the determined value to an interrogating device, as described below in conjunction with  FIG. 4 . According to an embodiment of the present invention such signal may be transmitted, for instance, when addressed by a RFID reader. For example, the RF encoding program  216  may determine that the environmental condition to which the monitored product has been exposed has transcended a minimum or maximum limit or range, based on the product environment data detected by the environmental sensor  222 . When an end user attempts to purchase the monitored product, for example at a supermarket, the monitored product may be scanned at a cash register equipped with an RFID reader. In the illustrated scenario, in response to receiving a signal from the cash register&#39;s RFID reader, according to an embodiment of the present invention, the active RFID tag  102  may transmit a purchase price value equal to zero indicating unacceptable quality of the monitored product due to exposure to an adverse environmental condition. This capability has numerous benefits, including preventing a sale of the product not suitable for use by the end user. In accordance with another embodiment of the present invention, in response to receiving a signal from the interrogating RFID reader device, the RF encoding program  216  may determine and report the remaining potency level of the monitored product. 
       FIG. 3  is a block diagram of a passive RFID tag with an environmental sensor which may be physically attached to a monitored product of the product delivery system of  FIG. 1  in accordance with another embodiment of the present invention. The passive RFID tag  300  may include known types of CPU  212 , memory  214  (such as EEPROM or SRAM), transceiver  208 , antenna  210  for the transmitter and receiver and environmental sensor  222 . At least in some embodiments, the environmental sensor  202  may be well-known in the art chemically based sensor that may be operable to detect, for example, monitored material phase transition/transformation. 
     In one specific example, the environmental sensor  222  may be a temperature sensor employing one or more heat sensitive fuses. A suitable device for this purpose may include a circuit as the recording mechanism and fuses in the circuit as the sensor. When a first threshold temperature is exceeded, a fuse opens at least one path through the circuit, thus changing the state of the recording mechanism. In one embodiment, opening the path changes the resonance frequency of the circuit. When a second threshold temperature is exceeded, a second fuse may open another path through the circuit, thus changing the state of the recording mechanism in a different manner than for the first threshold temperature. Similarly, when temperature decreases below a low-temperature threshold, a liquefied material may freeze, thereby changing a circuit path from open to closed (or vice versa) as above. Information stored by the recording mechanism may be utilized by the RF encoding program  216 , as described below in conjunction with  FIG. 4 . Temperature sensitive materials for the one or more fuses may be selected based upon the characteristics of the product or component to be monitored. 
     Some examples of fusible alloys that can be employed for the temperature sensor with their composition in weight-percent and melting points shown in parenthesis include, but are not limited to, Cs 73.71 K 22.14 Na 4.14 (−78.2° C.), Hg 91.5 Tl 8.5 (−58° C.), Hg 100 (−38.8° C.), Cs 77.0 K 23.0 (−38.8° C.), K 78.0 Na 22.0 (−11° C.), Ga 62.5 In 21.5 Sn 16.0 (10.7° C.), Ga 75.5 In 24.5 (15.7° C.), Ga 100 (29.8° C.), Bi 32.5 In 51.0 Sn 16.5 (60.5° C.), Bi 50.0 Pb 25.0 Sn 12.5, Cd 12.5 (71° C.), Bi 50.0 Pb 31.2 Sn 18.8 (97° C.), Bi 56.5 Pb 43.5 (125° C.), Sn 62.3 Pb 37.7 (183° C.), and Sn 91 Zn 9 (198° C.). In other embodiments a variety of brittle materials may be employed for environmental sensing purposes. Thus, in the passive RFID tag  300  the environmental sensor component  222  may also be passive. 
     As previously indicated, passive RFID tags  300  do not require battery for transmission since generally, they are powered by the reader using an induction mechanism (an electromagnetic field is emitted by the reader antenna and received by the antenna, such as antenna  210 , localized on the passive RFID tag). This power may be used by the passive RFID tag  300  to obtain environmental data from the environmental sensor  222 , invoke the RF encoding program  216  which may execute on the CPU  212  to read and analyze the environmental data and transmit a signal back to the reader, carrying the data, such as, for example, a discounted purchase price value or remaining potency value. It should be noted that if the RFID tag  300  employs chemically-based environmental sensor  222  capable of measuring various stages of material deterioration, such RFID tag  300  may not necessarily need power to collect environmental data. The memory  214  may contain the RF encoding program  216 . 
       FIG. 4  is a flowchart of the operation of an RF encoding program embedded within an active RFID tag of  FIG. 2  and/or a passive RFID tag of  FIG. 3  in accordance with an embodiment of the present invention. It should be appreciated that  FIG. 4  is only provided as an illustration of one implementation of RF encoding program and is not intended to imply any limitation with regard to the environments in which different embodiments may be implemented. At  402 , when an RFID tag  105  such as either active RFID tag  200  or passive RFID tag  300  is attached to a particular product item, in an embodiment of the present invention, the corresponding RF encoding program  216  may initialize the RFID tag  105  by, for example, establishing baseline values. In an embodiment of the present invention, environmental sensor  222  may optionally include a plurality of reference elements (not shown). It should be noted that environmental sensor  222  need not have a reference element. Reference elements may enable the cross validation of environmental data and may establish baselines. This may be important for chemical measurements, for biological environmental sensors, and for any sensor that measures two or more variables and at least one of the variables is dependent on or proportional to the other. In an embodiment of the present invention, environmental sensor  222  may have a plurality of associated reference elements. In an embodiment, a reference element provides a predetermined baseline and/or calibrated value to which environmental data subsequently obtained by the environmental sensor  222  can be compared internally. In an embodiment, the predetermined baseline values may be initialized by employing a calibration signal transmitted, for example by a RFID reader. In an embodiment of the present invention, in response to receiving a calibration signal, RF encoding program  216  may store the baseline values in memory  214 . 
     At  404 , as the product with the attached RFID tag  101  is transported and stored from the packaging location  106  to the point of sale location  116 , environmental sensor  222  may take a plurality of environmental measurements describing environmental conditions to which the monitored product has been subjected prior to sale. In an embodiment of the present invention periodic measurements may be taken by an active RFID tag  200  and each measurement may be stored, for example as historical data, in memory  214  along with time data indicating the time of sensing the environment condition. In an alternative embodiment, product manufacturer may provide an upper and lower product degradation thresholds. In this embodiment, an obtained environmental condition value may be stored in memory  214  when it crosses the upper or lower product degradation threshold. For example, environmental data may include cumulative deviation from upper and/or lower degradation threshold. As indicated above, environmental sensor  222  may sense the environmental condition periodically or otherwise along the product route to a point of sale terminal, such as cash register. How frequently the environmental sensor should sample and store measurements can be determined in a variety of ways and is an implementation decision. Alternatively, in a manufacturing environment, RFID tag  105  may take environmental measurements during various stages of manufacture. 
     Next, RF encoding program  216  may continue storing obtained environmental data (decision  406 , no branch) until RF encoding program  216  detects a signal transmitted by an interrogating RFID reader, such as a point of sale system with a connected RFID reader, (decision  406 , yes branch). Such interrogating signal may either energize passive RFID tag  300  or wake up active RFID tag  200  depending on the particular type of RFID tags being implemented. In response to receiving the signal from the interrogating RFID tag reader, at  408 , RF encoding program  216  may perform a comparison between the stored baseline data and recorded environmental data. For instance, RF encoding program  216  may compare baseline value with a cumulative deviation value. 
     According to an embodiment of the present invention, at  410 , RF encoding program  216  may determine whether the environmental conditions to which a monitored product has been subjected during its movement through a supply chain (recorded environmental data) are within acceptable limits from baseline values. For example, if the monitored product/material loses its effectiveness (e.g. potency) at 40° F. but becomes unusable once it is exposed to 32° F., RF encoding program  216  may determine that the temperature exposure is within acceptable limits when recorded temperature is in the range of 41° F. to 33° F. In various embodiments, the acceptable range of environmental measurement values may be implementation decision and may be provided by a product manufacturer. 
     In an embodiment of the present invention, in response to determining that environmental conditions had no adverse effects on the quality of monitored product (decision  410 , yes branch), at  412  RF encoding program  216  may generate an RFID message indicating no discount should be applied to a predetermined purchase price of the monitored product. Continuing with the above example, the RF encoding program  216  may generate this message if the recorded temperature value is above the potency level threshold (40° F.). In an embodiment, the generated RFID message may include other data associated with the monitored product stored in memory  214 . Such information may include, for example, product manufacturer/supplier code, date information, and the like. 
     In response to determining that the environmental conditions to which a monitored product has been subjected during its movement through a supply chain or manufacturing are not within acceptable limits from baseline values (decision  410 , no branch), RF encoding program  216  may next determine, at  414 , whether the monitored product is suitable for use by a product end user. In an embodiment of the present invention, RF encoding program  216  may determine whether the exposure to adverse environmental conditions may have caused an irreversible degradation of the monitored product. In various embodiments the method of determining the remaining effectiveness (potency) of the product may be product specific and may be implemented based on one or more criteria provided by the product manufacturer/supplier. According to an embodiment of the present invention, in response to determining that the monitored product is not suitable for use (decision  414 , no branch), RF encoding program  216  may generate (at  418 ) RFID message indicating unacceptable quality of the monitored product in order to prevent any sale of such product. Continuing with the above example, the RF encoding program  216  may be generated when the monitored product has been exposed to temperatures equal to or below 32° F. In an embodiment, the RFID message generated by the RF encoding program  216  at  418  may include, for example, a purchase price value equal to zero. In addition, such message may include other data, such as environmental data associated with an adverse environmental condition that may have caused degradation of the product. Such information may include, for example, stored time data indicating the time of sensing the adverse environmental condition. The RF encoding program  216  may retrieve this data from the memory  214  prior to generating the message. 
     In response to determining that the monitored product is suitable for sale despite the exposure to the adverse environmental conditions (decision  414 , yes branch), such as recorded temperature exposure is in the range of 39° F. to 33° F. in the above example, the RF encoding program  216  may next determine, at  416 , a discount value corresponding to a degradation level and/or remaining potency of the monitored product. In a preferred embodiment, the discount value may be calculated based on a sliding scale dependent upon the magnitude and/or duration of the exposure. In the preferred embodiment a linear sliding scale may be used. Next, at  420 , RF encoding program  216  may generate a corresponding RFID message which may include the discount value and/or remaining potency of the monitored product (if used in manufacturing environment) as determined by the RF encoding program  216 . 
     In accordance with an embodiment of the present invention, once RF encoding program  216  generates at least one of the RFID messages described above (at  412 ,  418  or  420 ), at  422 , the RF encoding program  216  may transmit the generated message, as an RF signal, to the RFID tag reader integrated with a point of sale system, as a response to the interrogation signal received at  406 . In an embodiment, RF encoding program  216  may employ transceiver  208  to transmit the RF signal. 
     In summary, RFID tags described herein when attached to a monitored product provide capability of adjusting a purchase price of the monitored product based on various environmental data stored in such tags without interacting with any external system. Alternatively, RFID tags described herein may provide information related to the remaining potency of the monitored product. According to an embodiment of the present invention, the RFID tags  200 ,  300  may be configured and/or certified by a product manufacturer. This pre-approved configuration may advantageously sufficiently minimize any non-approved variations in the price adjustments. The selection of active  200  or passive  300  RFID tags for a particular application can depend upon one or more of the above stated considerations regarding RFID tags, product characteristics, environmental sensors, and their operation. 
     The one or more RF encoding program  216  may be stored on one or more of the computer-readable tangible storage devices for execution by one or more of the processors  212  via one or more of the memories  214  (which typically include cache memory). In the embodiment illustrated in  FIGS. 2 and 3 , each of the computer-readable tangible storage devices is a semiconductor storage device such as ROM, EPROM, flash memory or any other computer-readable tangible storage device that can store a computer program and digital information. The RF encoding program  216  can be loaded into one or more computer-readable tangible storage devices from an external computer. 
     RF encoding program  216  can be written in various programming languages including low-level, high-level, object-oriented or non object-oriented languages. Alternatively, the functions of RF encoding program  216  can be implemented in whole or in part by computer circuits and other hardware (not shown). 
     The description above has been presented for illustration purposes only. It is not intended to be an exhaustive description of the possible embodiments. One of ordinary skill in the art will understand that other combinations and embodiments are possible.