USRE42599E1 - Method of addressing messages and communications system - Google Patents
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Abstract
Description
This is a ContinuationMore than one reissue application has been filed for the reissue of U.S. Pat. No. 6,282,186, which reissue applications are the initial reissue application Ser. No. 10/652,573, filed Aug. 28, 2003 and now U.S. Pat. No. RE40,686, a continuation reissue application Ser. No. 11/862,121, filed Sep. 26, 2007, a continuation reissue application Ser. No. 11/862,130, filed Sep. 26, 2007, a continuation reissue application Ser. No. 11/862,124, filed Sep. 26, 2007, and the present continuation reissue application, which is a continuation application of the reissue application Ser. No. 11/862,121, filed Sep. 26, 2007, which is a continuation application of the reissue application Ser. No. 10/652,573, filed Aug. 28, 2003, which is a reissue application of U.S. Pat. No. 6,282,186 having U.S. patent application Ser. No. 09/556,235, which is a continuation application of U.S. patent application Ser. No. 09/026,050, filed Feb. 19, 1998, now U.S. Pat. No. 6,061,344 and titled “Method of Addressing Messages and Communications System”.
This invention relates to communications protocols and to digital data communications. Still more particularly, the invention relates to data communications protocols in mediums such as radio communication or the like. The invention also relates to radio frequency identification devices for inventory control, object monitoring, determining the existence, location or movement of objects, or for remote automated payment.
Communications protocols are used in various applications. For example, communications protocols can be used in electronic identification systems. As large numbers of objects are moved in inventory, product manufacturing, and merchandising operations, there is a continuous challenge to accurately monitor the location and flow of objects. Additionally, there is a continuing goal to interrogate the location of objects in an inexpensive and streamlined manner. One way of tracking objects is with an electronic identification system.
One presently available electronic identification system utilizes a magnetic coupling system. In some cases, an identification device may be provided with a unique identification code in order to distinguish between a number of different devices. Typically, the devices are entirely passive (have no power supply), which results in a small and portable package. However, such identification systems are only capable of operation over a relatively short range, limited by the size of a magnetic field used to supply power to the devices and to communicate with the devices.
Another wireless electronic identification system utilizes a large, board level, active transponder device affixed to an object to be monitored which receives a signal from an interrogator. The device receives the signal, then generates and transmits a responsive signal. The interrogation signal and the responsive signal are typically radio-frequency (RF) signals produced by an RF transmitter circuit. Because active devices have their own power sources, and do not need to be in close proximity to an interrogator or reader to receive power via magnetic coupling. Therefore, active transponder devices tend to be more suitable for applications requiring tracking of a tagged device that may not be in close proximity to an interrogator. For example, active transponder devices tend to be more suitable for inventory control or tracking.
Electronic identification systems can also be used for remote payment. For example, when a radio frequency identification device passes an interrogator at a toll booth, the toll booth can determine the identity of the radio frequency identification device, and thus of the owner of the device, and debit an account held by the owner for payment of toll or can receive a credit card number against which the toll can be charged. Similarly, remote payment is possible for a variety of other goods or services.
A communication system typically includes two transponders: a commander station or interrogator, and a responder station or transponder device which replies to the interrogator.
If the interrogator has prior knowledge of the identification number of a device which the interrogator is looking for, it can specify that a response is requested only from the device with that identification number. Sometimes, such information is not available. For example, there are occasions where the interrogator is attempting to determine which of multiple devices are within communication range.
When the interrogator sends a message to a transponder device requesting a reply, there is a possibility that multiple transponder devices will attempt to respond simultaneously, causing a collision, and thus causing an erroneous message to be received by the interrogator. For example, if the interrogator sends out a command requesting that all devices within a communications range identify themselves, and gets a large number of simultaneous replies, the interrogator may not be able to interpret any of these replies. Thus, arbitration schemes are employed to permit communications free of collisions.
In one arbitration scheme or system, described in commonly assigned U.S. Pat. Nos. 5,627,544; 5,583,850; 5,500,650; and 5,365,551, all to Snodgrass et al. and all incorporated herein by reference, the interrogator sends a command causing each device of a potentially large number of responding devices to select a random number from a known range and use it as that device's arbitration number. By transmitting requests for identification to various subsets of the full range of arbitration numbers, and checking for an error-free response, the interrogator determines the arbitration number of every responder station capable of communicating at the same time. Therefore, the interrogator is able to conduct subsequent uninterrupted communication with devices, one at a time, by addressing only one device.
Another arbitration scheme is referred to as the Aloha or slotted Aloha scheme. This scheme is discussed in various references relating to communications, such as Digital Communications: Fundamentals and Application, Bernard Sklar, published January 1988 by Prentice Hall. In this type of scheme, a device will respond to an interrogator using one of many time domain slots selected randomly by the device. A problem with the Aloha scheme is that if there are many devices, or potentially many devices in the field (i.e. in communications range, capable of responding) then there must be many available slots or many collisions will occur. Having many available slots slows down replies. If the magnitude of the number of devices in a field is unknown, then many slots are needed. This results in the system slowing down significantly because the reply time equals the number of slots multiplied by the time period required for one reply.
An electronic identification system which can be used as a radio frequency identification device, arbitration schemes, and various applications for such devices are described in detail in commonly assigned U.S. patent application Ser. No. 08/705,043, filed Aug. 29, 1996, and Pat. No. 6,130,602, which is incorporated herein by reference.
The invention provides a wireless identification device configured to provide a signal to identify the device in response to an interrogation signal.
In one aspect, a method includes: receiving a first signal from an interrogator in accordance with an algorithm to identify a radio frequency identification (RFID) device in a field of the interrogator, the first signal comprising a first set of bits and requesting a response from one or more RFID devices in the field selected in accordance with at least the first set of bits; responsive to receiving the first signal, determining if the first set of bits is equal to a first portion of an identifier of the RFID device, and, if so, modulating a radio frequency (RF) field, provided by the interrogator, to communicate a reply to the interrogator in accordance with the algorithm; and receiving, in accordance with the algorithm, a retransmission of the first signal from the interrogator in response to the interrogator receiving the reply without detecting a collision.
One aspect of the invention provides a method of establishing wireless communications between an interrogator and individual ones of multiple wireless identification devices. The method comprises utilizing a tree search method to attempt to identify individual ones of the multiple wireless identification devices so as to be able to perform communications, without collision, between the interrogator and individual ones of the multiple wireless identification devices. A search tree is defined for the tree search method. The tree has multiple nodes respectively representing subgroups of the multiple wireless identification devices. The interrogator transmits a command at a node, requesting that devices within the subgroup represented by the node respond. The interrogator determines if a collision occurs in response to the command and, if not, repeats the command at the same node.
Another aspect of the invention provides a communications system comprising an interrogator, and a plurality of wireless identification devices configured to communicate with the interrogator in a wireless fashion. The interrogator is configured to employ tree searching to attempt to identify individual ones of the multiple wireless identification devices, so as to be able to perform communications without collision, between the interrogator and individual ones of the multiple wireless identification devices. The interrogator is configured to follow a search tree, the tree having multiple nodes respectively representing subgroups of the multiple wireless identification devices. The interrogator is configured to transmit a command at a node, requesting that devices within the subgroup represented by the node respond. The interrogator is further configured to determine if a collision occurs in response to the command and, if not, to repeat the command at the same node.
One aspect of the invention provides a radio frequency identification device comprising an integrated circuit including a receiver, a transmitter, and a microprocessor. In one embodiment, the integrated circuit is a monolithic single die single metal layer integrated circuit including the receiver, the transmitter, and the microprocessor. The device of this embodiment includes an active transponder, instead of a transponder which relies on magnetic coupling for power and therefore has a much greater range.
Preferred embodiments of the invention are described below with reference to the following accompanying drawings.
This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws “to promote the progress of science and useful arts” (Article 1, Section 8).
The device 12 transmits and receives radio frequency communications to and from an interrogator 26. An exemplary interrogator is described in commonly assigned U.S. patent application Ser. No. 08/907,689, filed Aug. 8, 1997 Pat. No. 6,289,209 and incorporated herein by reference. Preferably, the interrogator 26 includes an antenna 28, as well as dedicated transmitting and receiving circuitry, similar to that implemented on the integrated circuit 16.
Generally, the interrogator 26 transmits an interrogation signal or command 27 via the antenna 28. The device 12 receives the incoming interrogation signal via its antenna 14. Upon receiving the signal 27, the device 12 responds by generating and transmitting a responsive signal or reply 29. The responsive signal 29 typically includes information that uniquely identifies, or labels the particular device 12 that is transmitting, so as to identify any object or person with which the device 12 is associated. Although only one device 12 is shown in
The radio frequency data communication device 12 can be included in any appropriate housing or packaging. Various methods of manufacturing housings are described in commonly assigned U.S. patent application Ser. No. 08/800,037, filed Feb. 13, 1997, and Pat. No. 5,988,510 which is incorporated herein by reference.
If the power supply 18 is a battery, the battery can take any suitable form. Preferably, the battery type will be selected depending on weight, size, and life requirements for a particular application. In one embodiment, the battery 18 is a thin profile button-type cell forming a small, thin energy cell more commonly utilized in watches and small electronic devices requiring a thin profile. A conventional button-type cell has a pair of electrodes, an anode formed by one face and a cathode formed by an opposite face. In an alternative embodiment, the power source 18 comprises a series connected pair of button type cells. In other alternative embodiments, other types of suitable power source are employed.
The circuitry 16 further includes a backscatter transmitter and is configured to provide a responsive signal to the interrogator 26 by radio frequency. More particularly, the circuitry 16 includes a transmitter, a receiver, and memory such as is described in U.S. patent application Ser. No. 08/705,043 Pat. No. 6,130,602.
Radio frequency identification has emerged as a viable and affordable alternative to tagging or labeling small to large quantities of items. The interrogator 26 communicates with the devices 12 via an electromagnetic link, such as via an RF link (e.g., at microwave frequencies, in one embodiment), so all transmissions by the interrogator 26 are heard simultaneously by all devices 12 within range.
If the interrogator 26 sends out a command requesting that all devices 12 within range identify themselves, and gets a large number of simultaneous replies, the interrogator 26 may not be able to interpret any of these replies. Therefore, arbitration schemes are provided.
If the interrogator 26 has prior knowledge of the identification number of a device 12 which the interrogator 26 is looking for, it can specify that a response is requested only from the device 12 with that identification number. To target a command at a specific device 12, (i.e., to initiate point-on-point communication), the interrogator 26 must send a number identifying a specific device 12 along with the command. At start-up, or in a new or changing environment, these identification numbers are not known by the interrogator 26. Therefore, the interrogator 26 must identify all devices 12 in the field (within communication range) such as by determining the identification numbers of the devices 12 in the field. After this is accomplished, point-to-point communication can proceed as desired by the interrogator 26.
Generally speaking, RFID systems are a type of multiaccess communication system. The distance between the interrogator 26 and devices 12 within the field is typically fairly short (e.g., several meters), so packet transmission time is determined primarily by packet size and baud rate. Propagation delays are negligible. In such systems, there is a potential for a large number of transmitting devices 12 and there is a need for the interrogator 26 to work in a changing environment, where different devices 12 are swapped in and out frequently (e.g., as inventory is added or removed). In such systems, the inventors have determined that the use of random access methods work effectively for contention resolution (i.e., for dealing with collisions between devices 12 attempting to respond to the interrogator 26 at the same time).
RFID systems have some characteristics that are different from other communications systems. For example, one characteristic of the illustrated RFID systems is that the devices 12 never communicate without being prompted by the interrogator 26. This is in contrast to typical multiaccess systems where the transmitting units operate more independently. In addition, contention for the communication medium is short lived as compared to the ongoing nature of the problem in other multiaccess systems. For example, in a RFID system, after the devices 12 have been identified, the interrogator can communicate with them in a point-to-point fashion. Thus, arbitration in a RFID system is a transient rather than steady-state phenomenon. Further, the capability of a device 12 is limited by practical restrictions on size, power, and cost. The lifetime of a device 12 can often be measured in terms of number of transmissions before battery power is lost. Therefore, one of the most important measures of system performance in RFID arbitration is total time required to arbitrate a set of devices 12. Another measure is power consumed by the devices 12 during the process. This is in contrast to the measures of throughput and packet delay in other types of multiaccess systems.
Three variables are used: an arbitration value (AVALUE), an arbitration mask (AMASK), and a random value ID (RV). The interrogator sends an Identify command (IdentifyCmnd) causing each device of a potentially large number of responding devices to select a random number from a known range and use it as that device's arbitration number. The interrogator sends an arbitration value (AVALUE) and an arbitration mask (AMASK) to a set of devices 12. The receiving devices 12 evaluate the following equation: (AMASK & AVALUE)==(AMASK & RV) wherein “&” is a bitwise AND function, and wherein “==” is an equality function. If the equation evaluates to “1” (TRUE), then the device 12 will reply. If the equation evaluates to “0” (FALSE), then the device 12 will not reply. By performing this in a structured manner, with the number of bits in the arbitration mask being increased by one each time, eventually a device 12 will respond with no collisions. Thus, a binary search tree methodology is employed.
An example using actual numbers will now be provided using only four bits, for simplicity, reference being made to
Assume, for this example, that there are two devices 12 in the field, one with a random value (RV) of 1100 (binary), and another with a random value (RV) of 1010 (binary). The interrogator is tying to establish communications without collisions being caused by the two devices 12 attempting to communicate at the same time.
The interrogator sets AVALUE to 0000 (or “don't care” for all bits, as indicated by the character “X” in
Next, the interrogator sets AMASK to 0001 and AVALUE to 0000 and transmits an Identify command. Both devices 12 in the field have a zero for their least significant bit, and (AMASK & AVALUE)==(AMASK & RV) will be true for both devices 12. For the device 12 with a random value of 1100, the left side of the equation is evaluated as follows (0001 & 0000)=0000.
The right side is evaluated as (0001 & 1100)=0000. The left side equals the right side, so the equation is true for the device 12 with the random value of 1100. For the device 12 with a random value of 1010, the left side of the equation is evaluated as (0001 & 0000)=0000. The right side is evaluated as (0001 & 1010)=0000. The left side equals the right side, so the equation is true for the device 12 with the random value of 1010. Because the equation is true for both devices 12 in the field, both devices 12 in the field respond, and there is another collision.
Recursively, the interrogator next sets AMASK to 0011 with AVALUE still at 0000 and transmits an Identify command. (AMASK & AVALUE)==(AMASK & RV) is evaluated for both devices 12. For the device 12 with a random value of 1100, the left side of the equation is evaluated as follows (0011 & 0000)=0000. The right side is evaluated as (0011 & 1100)=0000. The left side equals the right side, so the equation is true for the device 12 with the random value of 1100, so this device 12 responds. For the device 12 with a random value of 1010, the left side of the equation is evaluated as (0011 & 0000)=0000. The right side is evaluated as (0011 & 1010)=0010. The left side does not equal the right side, so the equation is false for the device 12 with the random value of 1010, and this device 12 does not respond; Therefore, there is no collision, and the interrogator can determine the identity (e.g., an identification number) for the device 12 that does respond.
De-recursion takes place, and the devices 12 to the right for the same AMASK level are accessed when AVALUE is set at 0010, and AMASK is set to 0011.
The device 12 with the random value of 1010 receives a command and evaluates the equation (AMASK & AVALUE)==(AMASK & RV). The left side of the equation is evaluated as (0011 & 0010)=0010. The right side of the equation is evaluated as (0011 & 1010)=0010. The right side equals the left side, so the equation is true for the device 12 with the random value of 1010. Because there are no other devices 12 in the subtree, a good reply is returned by the device 12 with the random value of 1010. There is no collision, and the interrogator 26 can determine the identity (e.g., an identification number) for the device 12 that does respond.
By recursion, what is meant is that a function makes a call to itself. In other words, the function calls itself within the body of the function. After the called function returns, de-recursion takes place and execution continues at the place just after the function call; i.e. at the beginning of the statement after the function call.
For instance, consider a function that has four statements (numbered 1,2,3,4) in it, and the second statement is a recursive call. Assume that the fourth statement is a return statement. The first time through the loop (iteration 1) the function executes the statement 2 and (because it is a recursive call) calls itself causing iteration 2 to occur. When iteration 2 gets to statement 2, it calls itself making iteration 3. During execution in iteration 3 of statement 1, assume that the function does a return. The information that was saved on the stack from iteration 2 is loaded and the function resumes execution at statement 3 (in iteration 2), followed by the execution of statement 4 which is also a return statement. Since there are no more statements in the function, the function de-recurses to iteration 1. Iteration 1, had previously recursively called itself in statement 2. Therefore, it now executes statement 3 (in iteration 1). Following that it executes a return at statement 4. Recursion is known in the art.
Consider the following code which can be used to implement operation of the method shown in
- Arbitrate(AMASK, AVALUE)
- {
- collision=IdentifyCmnd(AMASK, AVALUE) if (collision) then
- {
- /* recursive call for left side */ Arbitrate ((AMASK<<1)+1, AVALUE)
- /* recursive call for right side */ Arbitrate ((AMASK<<1)+1, AVALUE+(AMASK+1))
- } /* endif */
- {
- collision=IdentifyCmnd(AMASK, AVALUE) if (collision) then
- }/* return */
- {
The symbol “<<” represents a bitwise left shift. “<<1” means shift left by one place. Thus, 0001<<1 would be 0010. Note, however, that AMASK is originally called with a value of zero, and 0000<<1 is still 0000. Therefore, for the first recursive call, AMASK=(AMASK<<1)+1. So for the first recursive call, the value of AMASK is 0000+0001=0001. For the second call, AMASK=(0001<<)+1=0010+1=0011. For the third recursive call, AMASK=(0011<<1)+1=0110+1=0111.
The routine generates values for AMASK and AVALUE to be used by the interrogator in an Identify command “IdentifyCmnd.” Note that the routine calls itself if there is a collision. De-recursion occurs when there is no collision. AVALUE and AMASK would have values such as the following assuming collisions take place all the way down to the bottom of the tree.
This sequence of AMASK, AVALUE binary numbers assumes that there are collisions all the way down to the bottom of the tree, at which point the Identify command sent by the interrogator is finally successful so that no collision occurs. Rows in the table for which the interrogator is successful in receiving a reply without collision are marked with the symbol “*”. Note that if the Identify command was successful at, for example, the third line in the table then the interrogator would stop going down that branch of the tree and start down another, so the sequence would be as shown in the following table.
This method is referred to as a splitting method. It works by splitting groups of colliding devices 12 into subsets that are resolved in turn. The splitting method can also be viewed as a type of tree search. Each split moves the method one level deeper in the tree. Either depth-first or breadth-first traversals of the tree can be employed. Depth first traversals are performed by using recursion, as is employed in the code listed above. Breadth-first traversals are accomplished by using a queue instead of recursion.
Either depth-first or breadth-first traversals of the tree can be employed. Depth first traversals are performed by using recursion, as is employed in the code listed above. Breadth-first traversals are accomplished by using a queue instead of recursion. The following is an example of code for performing a breadth-first traversal.
- Arbitrate(AMASK, AVALUE)
- {
- enqueue(0,0)
- while (queue !=empty)
- (AMASK,AVALUE)=dequeue( )
- collision=IdentifyCmnd(AMASK, AVALUE)
- if (collision) then
- {
- TEMP=AMASK+1
- NEW_AMASK=(AMASK<<1)+1
- enqueue(NEW_AMASK, AVALUE)
- enqueue(NEW_AMASK, AVALUE+TEMP)
- } /* endif */
- endwhile
- }/* return */.
- {
The symbol “!=” means not equal to. AVALUE and AMASK would have values such as those indicated in the following table for such code.
Rows in the table for which the interrogator is successful in receiving a reply without collision are marked with the symbol “*”.
The interrogator performs a tree search, either depth-first or breadth-first in a manner such as that described in connection with
When a single reply is read by the interrogator, for example, in node 52, the method described in connection with
AVALUE and AMASK would have values such as the following for a depth-first traversal in a situation similar to the one described above in connection with
Rows in the table for which the interrogator is successful in receiving a reply without collision are marked with the symbol “*”.
In operation, the interrogator transmits a command at a node, requesting that devices within the subgroup represented by the node respond. The interrogator determines if a collision occurs in response to the command and, if not, repeats the command at the same node.
In one alternative embodiment, the upper bound of the number of devices in the field (the maximum possible number of devices that could communicate with the interrogator) is determined, and the tree search method is started at a level 32, 34, 36, 38, or 40 in the tree depending on the determined upper bound. The level of the search tree on which to start the tree search is selected based on the determined maximum possible number of wireless identification devices that could communicate with the interrogator. The tree search is started at a level determined by taking the base two logarithm of the determined maximum possible number. More particularly, the tree search is started at a level determined by taking the base two logarithm of the power of two nearest the determined maximum possible number of devices 12. The level of the tree containing all subgroups of random values is considered level zero, and lower levels are numbered 1, 2, 3, 4, etc. consecutively.
Methods involving determining the upper bound on a set of devices and starting at a level in the tree depending on the determined upper bound are described in a commonly assigned patent application (attorney docket MI40-118) U.S. Pat. No. 6,118,789, naming Clifton W. Wood, Jr. as an inventor, titled “Method of Addressing Messages and Communications System,” filed concurrently herewith, and which is incorporated herein by reference.
In one alternative embodiment, a method involving starting at a level in the tree depending on a determined upper bound (such as the method described in the commonly assigned patent application mentioned above) is combined with a method comprising re-trying on the same node that gave a good reply, such as the method shown and described in connection with
Another arbitration method that can be employed is referred to as the “Aloha” method. In the Aloha method, every time a device 12 is involved in a collision, it waits a random period of time before retransmitting. This method can be improved by dividing time into equally sized slots and forcing transmissions to be aligned with one of these slots. This is referred to as “slotted Aloha.” In operation, the interrogator asks all devices 12 in the field to transmit their identification numbers in the next time slot. If the response is garbled, the interrogator informs the devices 12 that a collision has occurred, and the slotted Aloha scheme is put into action. This means that each device 12 in the field responds within an arbitrary slot determined by a randomly selected value. In other words, in each successive time slot, the devices 12 decide to transmit their identification number with a certain probability.
The Aloha method is based on a system operated by the University of Hawaii. In 1971, the University of Hawaii began operation of a system named Aloha. A communication satellite was used to interconnect several university computers by use of a random access protocol. The system operates as follows. Users or devices transmit at any time they desire. After transmitting, a user listens for an acknowledgment from the receiver or interrogator. Transmissions from different users will sometimes overlap in time (collide), causing reception errors in the data in each of the contending messages. The errors are detected by the receiver, and the receiver sends a negative acknowledgment to the users. When a negative acknowledgment is received, the messages are retransmitted by the colliding users after a random delay. If the colliding users attempted to retransmit without the random delay, they would collide again. If the user does not receive either an acknowledgment or a negative acknowledgment within a certain amount of time, the user “times out” and retransmits the message.
There is a scheme known as slotted Aloha which improves the Aloha scheme by requiring a small amount of coordination among stations. In the slotted Aloha scheme, a sequence of coordination pulses is broadcast to all stations (devices). As is the case with the pure Aloha scheme, packet lengths are constant. Messages are required to be sent in a slot time between synchronization pulses, and can be started only at the beginning of a time slot. This reduces the rate of collisions because only messages transmitted in the same slot can interfere with one another. The retransmission mode of the pure 11 Aloha scheme is modified for slotted Aloha such that if a negative acknowledgment occurs, the device retransmits after a random delay of an integer number of slot times.
Aloha methods are described in a commonly assigned patent application (attorney docket MI40-089) U.S. Pat. No. 6,275,476, naming Clifton W. Wood, Jr. as an inventor, titled “Method of Addressing Messages and Communications System,” filed concurrently herewith, and which is incorporated herein by reference.
In one alternative embodiment, an Aloha method (such as the method described in the commonly assigned patent application mentioned above) is combined with a method involving re-trying on the same node that gave a good reply, such as the method shown and described in connection with
In another embodiment, levels of the search tree are skipped. Skipping levels in the tree, after a collision caused by multiple devices 12 responding, reduces the number of subsequent collisions without adding significantly to the number of no replies. In real-time systems, it is desirable to have quick arbitration sessions on a set of devices 12 whose unique identification numbers are unknown. Level skipping reduces the number of collisions, both reducing arbitration time and conserving battery life on a set of devices 12. In one embodiment, every other level is skipped. In alternative embodiments, more than one level is skipped each time.
The trade off that must be considered in determining how many (if any) levels to skip with each decent down the tree is as follows. Skipping levels reduces the number of collisions, thus saving battery power in the devices 12. Skipping deeper (skipping more than one level) further reduces the number of collisions. The more levels that are skipped, the greater the reduction in collisions. However, skipping levels results in longer search times because the number of queries (Identify commands) increases. The more levels that are skipped, the longer the search times. Skipping just one level has an almost negligible effect on search time, but drastically reduces the number of collisions. If more than one level is skipped, search time increases substantially. Skipping every other level drastically reduces the number of collisions and saves battery power without significantly increasing the number of queries.
Level skipping methods are described in a commonly assigned patent application (attorney docket MI40-117) U.S. Pat. No. 6,072,801, naming Clifton W. Wood, Jr. and Don Hush as inventors, titled “Method of Addressing Messages, Method of Establishing Wireless Communications, and Communications System,” filed concurrently herewith, and which is incorporated herein by reference.
In one alternative embodiment, a level skipping method is combined with a method involving re-trying on the same node that gave a good reply, such as the method shown and described in connection with
In yet another alternative embodiment, any two or more of the methods described in the commonly assigned, concurrently filed, applications mentioned above are combined.
In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.
Claims (153)
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8645222B1 (en) | 2009-03-20 | 2014-02-04 | Jpmorgan Chase Bank, N.A. | System and methods for mobile ordering and payment |
Families Citing this family (94)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USRE43382E1 (en) | 1998-02-19 | 2012-05-15 | Round Rock Research, Llc | Method of addressing messages and communications systems |
US6118789A (en) | 1998-02-19 | 2000-09-12 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6072801A (en) | 1998-02-19 | 2000-06-06 | Micron Technology, Inc. | Method of addressing messages, method of establishing wireless communications, and communications system |
US6275476B1 (en) | 1998-02-19 | 2001-08-14 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6061344A (en) | 1998-02-19 | 2000-05-09 | Micron Technology, Inc. | Method of addressing messages and communications system |
US8538801B2 (en) | 1999-02-19 | 2013-09-17 | Exxonmobile Research & Engineering Company | System and method for processing financial transactions |
US6739487B2 (en) * | 1999-03-01 | 2004-05-25 | Thule Sweden Ab | Vertically engageable carrier foot |
US6323771B1 (en) * | 1999-04-09 | 2001-11-27 | James S. Payne | Method of identifying animals via universal identification scheme |
US7005985B1 (en) * | 1999-07-20 | 2006-02-28 | Axcess, Inc. | Radio frequency identification system and method |
US7627531B2 (en) | 2000-03-07 | 2009-12-01 | American Express Travel Related Services Company, Inc. | System for facilitating a transaction |
US7650314B1 (en) | 2001-05-25 | 2010-01-19 | American Express Travel Related Services Company, Inc. | System and method for securing a recurrent billing transaction |
US6988667B2 (en) * | 2001-05-31 | 2006-01-24 | Alien Technology Corporation | Methods and apparatuses to identify devices |
US7805378B2 (en) | 2001-07-10 | 2010-09-28 | American Express Travel Related Servicex Company, Inc. | System and method for encoding information in magnetic stripe format for use in radio frequency identification transactions |
US8635131B1 (en) | 2001-07-10 | 2014-01-21 | American Express Travel Related Services Company, Inc. | System and method for managing a transaction protocol |
US7503480B2 (en) | 2001-07-10 | 2009-03-17 | American Express Travel Related Services Company, Inc. | Method and system for tracking user performance |
US8548927B2 (en) | 2001-07-10 | 2013-10-01 | Xatra Fund Mx, Llc | Biometric registration for facilitating an RF transaction |
US20040236699A1 (en) | 2001-07-10 | 2004-11-25 | American Express Travel Related Services Company, Inc. | Method and system for hand geometry recognition biometrics on a fob |
US8001054B1 (en) | 2001-07-10 | 2011-08-16 | American Express Travel Related Services Company, Inc. | System and method for generating an unpredictable number using a seeded algorithm |
US7303120B2 (en) | 2001-07-10 | 2007-12-04 | American Express Travel Related Services Company, Inc. | System for biometric security using a FOB |
US7925535B2 (en) * | 2001-07-10 | 2011-04-12 | American Express Travel Related Services Company, Inc. | System and method for securing RF transactions using a radio frequency identification device including a random number generator |
US8294552B2 (en) | 2001-07-10 | 2012-10-23 | Xatra Fund Mx, Llc | Facial scan biometrics on a payment device |
US7735725B1 (en) | 2001-07-10 | 2010-06-15 | Fred Bishop | Processing an RF transaction using a routing number |
US7668750B2 (en) | 2001-07-10 | 2010-02-23 | David S Bonalle | Securing RF transactions using a transactions counter |
US9031880B2 (en) | 2001-07-10 | 2015-05-12 | Iii Holdings 1, Llc | Systems and methods for non-traditional payment using biometric data |
US7360689B2 (en) | 2001-07-10 | 2008-04-22 | American Express Travel Related Services Company, Inc. | Method and system for proffering multiple biometrics for use with a FOB |
US8960535B2 (en) * | 2001-07-10 | 2015-02-24 | Iii Holdings 1, Llc | Method and system for resource management and evaluation |
US9024719B1 (en) | 2001-07-10 | 2015-05-05 | Xatra Fund Mx, Llc | RF transaction system and method for storing user personal data |
US9454752B2 (en) | 2001-07-10 | 2016-09-27 | Chartoleaux Kg Limited Liability Company | Reload protocol at a transaction processing entity |
US7746215B1 (en) | 2001-07-10 | 2010-06-29 | Fred Bishop | RF transactions using a wireless reader grid |
USRE45416E1 (en) | 2001-07-10 | 2015-03-17 | Xatra Fund Mx, Llc | Processing an RF transaction using a routing number |
US7542942B2 (en) * | 2001-07-10 | 2009-06-02 | American Express Travel Related Services Company, Inc. | System and method for securing sensitive information during completion of a transaction |
US7762457B2 (en) | 2001-07-10 | 2010-07-27 | American Express Travel Related Services Company, Inc. | System and method for dynamic fob synchronization and personalization |
US7239226B2 (en) | 2001-07-10 | 2007-07-03 | American Express Travel Related Services Company, Inc. | System and method for payment using radio frequency identification in contact and contactless transactions |
US7889052B2 (en) | 2001-07-10 | 2011-02-15 | Xatra Fund Mx, Llc | Authorizing payment subsequent to RF transactions |
US8284025B2 (en) | 2001-07-10 | 2012-10-09 | Xatra Fund Mx, Llc | Method and system for auditory recognition biometrics on a FOB |
US7996324B2 (en) | 2001-07-10 | 2011-08-09 | American Express Travel Related Services Company, Inc. | Systems and methods for managing multiple accounts on a RF transaction device using secondary identification indicia |
US7193504B2 (en) * | 2001-10-09 | 2007-03-20 | Alien Technology Corporation | Methods and apparatuses for identification |
EP1454291B1 (en) * | 2001-12-11 | 2007-08-08 | Tagsys SA | Secure data tagging systems |
WO2003063103A1 (en) * | 2002-01-18 | 2003-07-31 | Georgia Tech Research Corporation | Monitoring and tracking of assets by utilizing wireless communications |
US8543423B2 (en) * | 2002-07-16 | 2013-09-24 | American Express Travel Related Services Company, Inc. | Method and apparatus for enrolling with multiple transaction environments |
US20040046642A1 (en) * | 2002-09-05 | 2004-03-11 | Honeywell International Inc. | Protocol for addressing groups of RFID tags |
US6805287B2 (en) | 2002-09-12 | 2004-10-19 | American Express Travel Related Services Company, Inc. | System and method for converting a stored value card to a credit card |
US7009526B2 (en) * | 2002-10-02 | 2006-03-07 | Battelle Memorial Institute | RFID system and method including tag ID compression |
US7515882B2 (en) * | 2002-12-17 | 2009-04-07 | Kelcourse Mark F | Apparatus, methods and articles of manufacture for a multi-band switch |
US7869770B2 (en) * | 2002-12-17 | 2011-01-11 | M/A-Com Technology Solutions Holdings, Inc. | Apparatus, methods and articles of manufacture for a multi-band switch |
JP2004259123A (en) * | 2003-02-27 | 2004-09-16 | Nec Micro Systems Ltd | Rfid (radio frequency identification) system and program for rfid |
US6970070B2 (en) * | 2003-05-08 | 2005-11-29 | Rsa Security Inc. | Method and apparatus for selective blocking of radio frequency identification devices |
US8429041B2 (en) | 2003-05-09 | 2013-04-23 | American Express Travel Related Services Company, Inc. | Systems and methods for managing account information lifecycles |
FR2857475B1 (en) * | 2003-07-10 | 2007-02-02 | Commissariat Energie Atomique | Device comprising a matrix of microsystems addressable individually by electromagnetic transmission and method of addressing such a device |
US8102244B2 (en) * | 2003-08-09 | 2012-01-24 | Alien Technology Corporation | Methods and apparatuses to identify devices |
US7119664B2 (en) * | 2003-09-17 | 2006-10-10 | Id Solutions, Inc. | Deep sleep in an RFID tag |
US7716160B2 (en) * | 2003-11-07 | 2010-05-11 | Alien Technology Corporation | Methods and apparatuses to identify devices |
US7880589B2 (en) * | 2004-02-06 | 2011-02-01 | Battelle Memorial Institute | Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture |
US7841120B2 (en) | 2004-03-22 | 2010-11-30 | Wilcox Industries Corp. | Hand grip apparatus for firearm |
US20050237157A1 (en) * | 2004-04-13 | 2005-10-27 | Impinj, Inc. | RFID tag systems, RFID tags and RFID processes with branch node indexing |
US20050237158A1 (en) * | 2004-04-13 | 2005-10-27 | Impinj, Inc. | RFID tag systems, RFID tags and RFID processes using N-ary FSK |
US20050237159A1 (en) * | 2004-04-13 | 2005-10-27 | Impinj, Inc. | RFID tag systems, RFID tags and RFID processes with reverse link burst mode |
DE102004018540A1 (en) * | 2004-04-14 | 2005-11-03 | Atmel Germany Gmbh | Method for selecting one or more transponders |
DE102004018541A1 (en) * | 2004-04-14 | 2005-11-17 | Atmel Germany Gmbh | Method for selecting one or more transponders |
US8604910B2 (en) * | 2004-07-13 | 2013-12-10 | Cisco Technology, Inc. | Using syslog and SNMP for scalable monitoring of networked devices |
US7318550B2 (en) | 2004-07-01 | 2008-01-15 | American Express Travel Related Services Company, Inc. | Biometric safeguard method for use with a smartcard |
BRPI0513354A (en) * | 2004-07-15 | 2008-05-06 | Mastercard International Inc | electronic payment system and collision and vacancy detection method for processing a contactless payment card transaction |
US7750793B2 (en) * | 2004-07-29 | 2010-07-06 | Emc Corporation | Methods and apparatus for RFID device authentication |
US7920050B2 (en) * | 2004-07-29 | 2011-04-05 | Emc Corporation | Proxy device for enhanced privacy in an RFID system |
US7581678B2 (en) | 2005-02-22 | 2009-09-01 | Tyfone, Inc. | Electronic transaction card |
WO2006133087A2 (en) * | 2005-06-03 | 2006-12-14 | Ems Technologies, Inc. | Method and system for discovering antenna line devices |
US7953826B2 (en) | 2005-07-14 | 2011-05-31 | Cisco Technology, Inc. | Provisioning and redundancy for RFID middleware servers |
KR100693006B1 (en) * | 2005-07-26 | 2007-03-12 | 삼성전자주식회사 | ID anti-collision method using data structure to be applied to RFID system |
KR100625675B1 (en) * | 2005-09-30 | 2006-09-12 | 에스케이 텔레콤주식회사 | Method for identifying tags using adaptive binary tree splitting technique in rfid system and rfid system therefor |
TW200820095A (en) * | 2005-10-25 | 2008-05-01 | Nxp Bv | Method of reading data from transponders through a reader, a transponder, and a reader |
US8698603B2 (en) * | 2005-11-15 | 2014-04-15 | Cisco Technology, Inc. | Methods and systems for automatic device provisioning in an RFID network using IP multicast |
US8378786B2 (en) * | 2006-02-03 | 2013-02-19 | Emc Corporation | Security provision in standards-compliant RFID systems |
WO2007103254A2 (en) * | 2006-03-02 | 2007-09-13 | Axcess International Inc. | System and method for determining location, directionality, and velocity of rfid tags |
US20070285241A1 (en) * | 2006-03-20 | 2007-12-13 | Axcess International Inc. | Multi-Tag Tracking Systems and Methods |
US7800503B2 (en) * | 2006-05-11 | 2010-09-21 | Axcess International Inc. | Radio frequency identification (RFID) tag antenna design |
WO2008062331A2 (en) * | 2006-11-23 | 2008-05-29 | International Business Machines Corporation | Privacy method, device and computer program |
US7924141B2 (en) * | 2006-12-01 | 2011-04-12 | Round Rock Research, Llc | RFID communication systems and methods, and RFID readers and systems |
US7967214B2 (en) | 2006-12-29 | 2011-06-28 | Solicore, Inc. | Card configured to receive separate battery |
WO2008082617A2 (en) | 2006-12-29 | 2008-07-10 | Solicore, Inc. | Mailing apparatus for powered cards |
US7973644B2 (en) * | 2007-01-30 | 2011-07-05 | Round Rock Research, Llc | Systems and methods for RFID tag arbitration where RFID tags generate multiple random numbers for different arbitration sessions |
US8134452B2 (en) * | 2007-05-30 | 2012-03-13 | Round Rock Research, Llc | Methods and systems of receiving data payload of RFID tags |
CN101430753B (en) * | 2007-11-08 | 2011-01-19 | 中兴通讯股份有限公司 | Label anti-collision method for radio frequency recognition system |
US9741027B2 (en) | 2007-12-14 | 2017-08-22 | Tyfone, Inc. | Memory card based contactless devices |
US8638194B2 (en) * | 2008-07-25 | 2014-01-28 | Axcess International, Inc. | Multiple radio frequency identification (RFID) tag wireless wide area network (WWAN) protocol |
US7961101B2 (en) | 2008-08-08 | 2011-06-14 | Tyfone, Inc. | Small RFID card with integrated inductive element |
US8451122B2 (en) | 2008-08-08 | 2013-05-28 | Tyfone, Inc. | Smartcard performance enhancement circuits and systems |
US20100033310A1 (en) * | 2008-08-08 | 2010-02-11 | Narendra Siva G | Power negotation for small rfid card |
EP2401708A4 (en) | 2009-02-24 | 2012-08-15 | Tyfone Inc | Contactless device with miniaturized antenna |
CN101860948B (en) * | 2009-04-13 | 2014-07-30 | 华为技术有限公司 | Method, equipment and system for regulating power consumption |
US9832769B2 (en) | 2009-09-25 | 2017-11-28 | Northwestern University | Virtual full duplex network communications |
US20110116421A1 (en) * | 2009-09-25 | 2011-05-19 | Dongning Guo | Rapid on-off-division duplex network communications |
US9734645B2 (en) * | 2010-10-15 | 2017-08-15 | The Chamberlain Group, Inc. | Method and apparatus pertaining to message-based functionality |
US9160906B2 (en) | 2011-02-03 | 2015-10-13 | Jason R. Bond | Head-mounted face image capturing devices and systems |
US8573866B2 (en) * | 2011-02-03 | 2013-11-05 | Jason R. Bond | Head-mounted face image capturing devices and systems |
Citations (51)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4075632A (en) | 1974-08-27 | 1978-02-21 | The United States Of America As Represented By The United States Department Of Energy | Interrogation, and detection system |
US4862453A (en) | 1986-10-03 | 1989-08-29 | The Marconi Company Limited | Communication system |
US4926182A (en) | 1986-05-30 | 1990-05-15 | Sharp Kabushiki Kaisha | Microwave data transmission apparatus |
US5142694A (en) | 1989-07-24 | 1992-08-25 | Motorola, Inc. | Reporting unit |
US5365551A (en) | 1992-12-15 | 1994-11-15 | Micron Technology, Inc. | Data communication transceiver using identification protocol |
US5479416A (en) | 1993-09-30 | 1995-12-26 | Micron Technology, Inc. | Apparatus and method for error detection and correction in radio frequency identification device |
US5500650A (en) | 1992-12-15 | 1996-03-19 | Micron Technology, Inc. | Data communication method using identification protocol |
US5550547A (en) | 1994-09-12 | 1996-08-27 | International Business Machines Corporation | Multiple item radio frequency tag identification protocol |
US5621412A (en) | 1994-04-26 | 1997-04-15 | Texas Instruments Incorporated | Multi-stage transponder wake-up, method and structure |
US5625628A (en) | 1995-03-15 | 1997-04-29 | Hughes Electronics | Aloha optimization |
US5649296A (en) | 1995-06-19 | 1997-07-15 | Lucent Technologies Inc. | Full duplex modulated backscatter system |
WO1997048216A2 (en) | 1996-06-10 | 1997-12-18 | At & T Wireless Services, Inc. | Registration of mobile packet data terminals after disaster |
US5805586A (en) | 1995-05-02 | 1998-09-08 | Motorola Inc. | Method, device and data communication system for multilink polling |
US5966471A (en) | 1997-12-23 | 1999-10-12 | United States Of America | Method of codebook generation for an amplitude-adaptive vector quantization system |
US5974078A (en) | 1993-03-17 | 1999-10-26 | Micron Technology, Inc. | Modulated spread spectrum in RF identification systems method |
US5988510A (en) | 1997-02-13 | 1999-11-23 | Micron Communications, Inc. | Tamper resistant smart card and method of protecting data in a smart card |
US6038455A (en) | 1995-09-25 | 2000-03-14 | Cirrus Logic, Inc. | Reverse channel reuse scheme in a time shared cellular communication system |
US6061344A (en) | 1998-02-19 | 2000-05-09 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6072801A (en) | 1998-02-19 | 2000-06-06 | Micron Technology, Inc. | Method of addressing messages, method of establishing wireless communications, and communications system |
US6075973A (en) | 1998-05-18 | 2000-06-13 | Micron Technology, Inc. | Method of communications in a backscatter system, interrogator, and backscatter communications system |
US6097292A (en) | 1997-04-01 | 2000-08-01 | Cubic Corporation | Contactless proximity automated data collection system and method |
US6104333A (en) | 1996-12-19 | 2000-08-15 | Micron Technology, Inc. | Methods of processing wireless communication, methods of processing radio frequency communication, and related systems |
US6118789A (en) | 1998-02-19 | 2000-09-12 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6130623A (en) * | 1996-12-31 | 2000-10-10 | Lucent Technologies Inc. | Encryption for modulated backscatter systems |
US6130602A (en) | 1996-05-13 | 2000-10-10 | Micron Technology, Inc. | Radio frequency data communications device |
US6150921A (en) | 1996-10-17 | 2000-11-21 | Pinpoint Corporation | Article tracking system |
US6169474B1 (en) | 1998-04-23 | 2001-01-02 | Micron Technology, Inc. | Method of communications in a backscatter system, interrogator, and backscatter communications system |
US6177858B1 (en) | 1995-12-01 | 2001-01-23 | Pierre Raimbault | Method for remotely interrogating tags, and station and tag implementing said method |
US6185307B1 (en) | 1997-07-16 | 2001-02-06 | Gilbarco Inc. | Cryptography security for remote dispenser transactions |
US6192222B1 (en) | 1998-09-03 | 2001-02-20 | Micron Technology, Inc. | Backscatter communication systems, interrogators, methods of communicating in a backscatter system, and backscatter communication methods |
US6216132B1 (en) | 1997-11-20 | 2001-04-10 | International Business Machines Corporation | Method and system for matching consumers to events |
US6243012B1 (en) | 1996-12-31 | 2001-06-05 | Lucent Technologies Inc. | Inexpensive modulated backscatter reflector |
US6265962B1 (en) | 1997-09-03 | 2001-07-24 | Micron Technology, Inc. | Method for resolving signal collisions between multiple RFID transponders in a field |
US6275476B1 (en) | 1998-02-19 | 2001-08-14 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6289209B1 (en) | 1996-12-18 | 2001-09-11 | Micron Technology, Inc. | Wireless communication system, radio frequency communications system, wireless communications method, radio frequency communications method |
US6288629B1 (en) | 1997-05-23 | 2001-09-11 | Intermec Ip Corp. | Method of using write—ok flag for radio frequency (RF) transponders (RF Tags) |
US6324211B1 (en) | 1998-04-24 | 2001-11-27 | Micron Technology, Inc. | Interrogators communication systems communication methods and methods of processing a communication signal |
US6415439B1 (en) | 1997-02-04 | 2002-07-02 | Microsoft Corporation | Protocol for a wireless control system |
US6459726B1 (en) | 1998-04-24 | 2002-10-01 | Micron Technology, Inc. | Backscatter interrogators, communication systems and backscatter communication methods |
US6566997B1 (en) | 1999-12-03 | 2003-05-20 | Hid Corporation | Interference control method for RFID systems |
US6570487B1 (en) | 1997-01-24 | 2003-05-27 | Axcess Inc. | Distributed tag reader system and method |
US6707376B1 (en) | 2002-08-09 | 2004-03-16 | Sensormatic Electronics Corporation | Pulsed power method for increased read range for a radio frequency identification reader |
US6714559B1 (en) | 1991-12-04 | 2004-03-30 | Broadcom Corporation | Redundant radio frequency network having a roaming terminal communication protocol |
US6778096B1 (en) | 1997-11-17 | 2004-08-17 | International Business Machines Corporation | Method and apparatus for deploying and tracking computers |
US6784787B1 (en) | 1997-11-14 | 2004-08-31 | Btg International Limited | Identification system |
US6812824B1 (en) * | 1996-10-17 | 2004-11-02 | Rf Technologies, Inc. | Method and apparatus combining a tracking system and a wireless communication system |
US6850510B2 (en) | 1995-10-05 | 2005-02-01 | Broadcom Corporation | Hierarchical data collection network supporting packetized voice communications among wireless terminals and telephones |
US20050060069A1 (en) | 1997-10-22 | 2005-03-17 | Breed David S. | Method and system for controlling a vehicle |
US6919793B2 (en) | 1994-09-09 | 2005-07-19 | Intermec Ip Corp. | Radio frequency identification system write broadcast capability |
US6950009B1 (en) * | 1996-11-29 | 2005-09-27 | X-Cyte, Inc. | Dual mode transmitter/receiver and decoder for RF transponder units |
US7026935B2 (en) | 2003-11-10 | 2006-04-11 | Impinj, Inc. | Method and apparatus to configure an RFID system to be adaptable to a plurality of environmental conditions |
Family Cites Families (40)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5168510A (en) | 1984-03-06 | 1992-12-01 | Comsource Systems | Spread spectrum-time diversity communications systems and transceivers for multidrop area networks |
US4761778A (en) | 1985-04-11 | 1988-08-02 | Massachusetts Institute Of Technology | Coder-packetizer for random accessing in digital communication with multiple accessing |
US4799059A (en) | 1986-03-14 | 1989-01-17 | Enscan, Inc. | Automatic/remote RF instrument monitoring system |
US4796023A (en) | 1986-12-05 | 1989-01-03 | King Robert E | Stabilized binary tree protocol |
CA1290020C (en) | 1987-02-09 | 1991-10-01 | Steven Messenger | Wireless local area network |
US4845504A (en) | 1987-04-08 | 1989-07-04 | M/A-Com, Inc. | Mobile radio network for nationwide communications |
NL8700861A (en) | 1987-04-13 | 1988-11-01 | Nedap Nv | Read, write system with miniature information carrier. |
RU2109402C1 (en) | 1987-10-27 | 1998-04-20 | Энтон Найсен Пол | Device for two-way communication between transmitter/receiver units |
US4969146A (en) | 1987-11-10 | 1990-11-06 | Echelon Systems Corporation | Protocol for network having a plurality of intelligent cells |
US4955018A (en) | 1987-11-10 | 1990-09-04 | Echelon Systems Corporation | Protocol for network having plurality of intelligent cells |
AU626013B2 (en) | 1988-07-04 | 1992-07-23 | Sony Corporation | A thin electronic device having an integrated circuit chip and a power battery and a method for producing same |
NO169983C (en) | 1988-10-27 | 1992-08-26 | Micro Design As | Method and arrangement for individual identification |
US5025486A (en) | 1988-12-09 | 1991-06-18 | Dallas Semiconductor Corporation | Wireless communication system with parallel polling |
US5150310A (en) | 1989-08-30 | 1992-09-22 | Consolve, Inc. | Method and apparatus for position detection |
US5124697A (en) | 1989-10-16 | 1992-06-23 | Motorola, Inc. | Acknowledge-back pager |
SE464946B (en) | 1989-11-10 | 1991-07-01 | Philips Norden Ab | Oeverfoeringssystem comprising a fraagestation and a number of transponders |
GB2238147B (en) | 1989-11-16 | 1993-04-21 | Gen Electric Co Plc | Radio telemetry systems |
CA2034878C (en) | 1990-03-08 | 2002-04-02 | Craig S. Hyatt | Programmable controller communication module |
US5640151A (en) | 1990-06-15 | 1997-06-17 | Texas Instruments Incorporated | Communication system for communicating with tags |
US5121407A (en) | 1990-09-27 | 1992-06-09 | Pittway Corporation | Spread spectrum communications system |
US5144668A (en) | 1991-01-25 | 1992-09-01 | Motorola, Inc. | Signal overlap detection in a communication system |
US5266925A (en) | 1991-09-30 | 1993-11-30 | Westinghouse Electric Corp. | Electronic identification tag interrogation method |
US5461627A (en) * | 1991-12-24 | 1995-10-24 | Rypinski; Chandos A. | Access protocol for a common channel wireless network |
US5231646A (en) | 1992-03-16 | 1993-07-27 | Kyros Corporation | Communications system |
US5373503A (en) | 1993-04-30 | 1994-12-13 | Information Technology, Inc. | Group randomly addressed polling method |
US5790946A (en) | 1993-07-15 | 1998-08-04 | Rotzoll; Robert R. | Wake up device for a communications system |
US5449296A (en) * | 1994-03-07 | 1995-09-12 | Cabel-Con, Inc. Usa | Cable connector apparatus for preventing radiation leakage |
US5530702A (en) | 1994-05-31 | 1996-06-25 | Ludwig Kipp | System for storage and communication of information |
US6812852B1 (en) * | 1994-09-09 | 2004-11-02 | Intermac Ip Corp. | System and method for selecting a subset of autonomous and independent slave entities |
US5619648A (en) | 1994-11-30 | 1997-04-08 | Lucent Technologies Inc. | Message filtering techniques |
US5940006A (en) | 1995-12-12 | 1999-08-17 | Lucent Technologies Inc. | Enhanced uplink modulated backscatter system |
JP3540109B2 (en) | 1996-12-24 | 2004-07-07 | 富士通株式会社 | Data compression method and apparatus |
US5952922A (en) | 1996-12-31 | 1999-09-14 | Lucent Technologies Inc. | In-building modulated backscatter system |
US5914671A (en) | 1997-02-27 | 1999-06-22 | Micron Communications, Inc. | System and method for locating individuals and equipment, airline reservation system, communication system |
JP3690285B2 (en) | 2001-02-01 | 2005-08-31 | 日本ビクター株式会社 | Color combining optical system and projection display apparatus using the same |
US7688764B2 (en) | 2002-06-20 | 2010-03-30 | Motorola, Inc. | Method and apparatus for speaker arbitration in a multi-participant communication session |
US7667575B2 (en) | 2004-07-30 | 2010-02-23 | Reva Systems Corporation | Location virtualization in an RFID system |
US20080007421A1 (en) | 2005-08-02 | 2008-01-10 | University Of Houston | Measurement-while-drilling (mwd) telemetry by wireless mems radio units |
US7924141B2 (en) | 2006-12-01 | 2011-04-12 | Round Rock Research, Llc | RFID communication systems and methods, and RFID readers and systems |
US7973644B2 (en) * | 2007-01-30 | 2011-07-05 | Round Rock Research, Llc | Systems and methods for RFID tag arbitration where RFID tags generate multiple random numbers for different arbitration sessions |
-
1998
- 1998-02-19 US US09/026,050 patent/US6061344A/en not_active Expired - Lifetime
-
2000
- 2000-04-24 US US09/556,235 patent/US6282186B1/en not_active Expired - Lifetime
-
2003
- 2003-08-28 US US10/652,573 patent/USRE40686E1/en not_active Expired - Lifetime
-
2007
- 2007-09-26 US US11/862,121 patent/USRE41471E1/en not_active Expired - Lifetime
- 2007-09-26 US US11/862,124 patent/USRE41352E1/en not_active Expired - Lifetime
- 2007-09-26 US US11/862,130 patent/USRE42254E1/en not_active Expired - Lifetime
-
2009
- 2009-08-14 US US12/541,882 patent/USRE42599E1/en not_active Expired - Lifetime
Patent Citations (70)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4075632A (en) | 1974-08-27 | 1978-02-21 | The United States Of America As Represented By The United States Department Of Energy | Interrogation, and detection system |
US4926182A (en) | 1986-05-30 | 1990-05-15 | Sharp Kabushiki Kaisha | Microwave data transmission apparatus |
US4862453A (en) | 1986-10-03 | 1989-08-29 | The Marconi Company Limited | Communication system |
US5142694A (en) | 1989-07-24 | 1992-08-25 | Motorola, Inc. | Reporting unit |
US6714559B1 (en) | 1991-12-04 | 2004-03-30 | Broadcom Corporation | Redundant radio frequency network having a roaming terminal communication protocol |
US5627544A (en) | 1992-12-15 | 1997-05-06 | Micron Technology, Inc. | Data communication method using identification protocol |
US5365551A (en) | 1992-12-15 | 1994-11-15 | Micron Technology, Inc. | Data communication transceiver using identification protocol |
US5500650A (en) | 1992-12-15 | 1996-03-19 | Micron Technology, Inc. | Data communication method using identification protocol |
US5583850A (en) | 1992-12-15 | 1996-12-10 | Micron Technology, Inc. | Data communication system using identification protocol |
US5841770A (en) | 1992-12-15 | 1998-11-24 | Micron Technology, Inc. | Data communication system using indentification protocol |
US5974078A (en) | 1993-03-17 | 1999-10-26 | Micron Technology, Inc. | Modulated spread spectrum in RF identification systems method |
US5479416A (en) | 1993-09-30 | 1995-12-26 | Micron Technology, Inc. | Apparatus and method for error detection and correction in radio frequency identification device |
US5608739A (en) | 1993-09-30 | 1997-03-04 | Micron Technology, Inc. | Apparatus and method for error detection and correction in radio frequency identification device |
US5621412A (en) | 1994-04-26 | 1997-04-15 | Texas Instruments Incorporated | Multi-stage transponder wake-up, method and structure |
US6919793B2 (en) | 1994-09-09 | 2005-07-19 | Intermec Ip Corp. | Radio frequency identification system write broadcast capability |
US5550547A (en) | 1994-09-12 | 1996-08-27 | International Business Machines Corporation | Multiple item radio frequency tag identification protocol |
US5625628A (en) | 1995-03-15 | 1997-04-29 | Hughes Electronics | Aloha optimization |
US5805586A (en) | 1995-05-02 | 1998-09-08 | Motorola Inc. | Method, device and data communication system for multilink polling |
US5649296A (en) | 1995-06-19 | 1997-07-15 | Lucent Technologies Inc. | Full duplex modulated backscatter system |
US6038455A (en) | 1995-09-25 | 2000-03-14 | Cirrus Logic, Inc. | Reverse channel reuse scheme in a time shared cellular communication system |
US6850510B2 (en) | 1995-10-05 | 2005-02-01 | Broadcom Corporation | Hierarchical data collection network supporting packetized voice communications among wireless terminals and telephones |
US6177858B1 (en) | 1995-12-01 | 2001-01-23 | Pierre Raimbault | Method for remotely interrogating tags, and station and tag implementing said method |
US7385477B2 (en) | 1996-05-13 | 2008-06-10 | Keystone Technology Solutions, Llc | Radio frequency data communications device |
US6130602A (en) | 1996-05-13 | 2000-10-10 | Micron Technology, Inc. | Radio frequency data communications device |
US6771634B1 (en) | 1996-06-10 | 2004-08-03 | At&T Wireless Services, Inc. | Registration of mobile packet data terminals after disaster |
WO1997048216A2 (en) | 1996-06-10 | 1997-12-18 | At & T Wireless Services, Inc. | Registration of mobile packet data terminals after disaster |
US6157633A (en) | 1996-06-10 | 2000-12-05 | At&T Wireless Sucs. Inc. | Registration of mobile packet data terminals after disaster |
US6483427B1 (en) * | 1996-10-17 | 2002-11-19 | Rf Technologies, Inc. | Article tracking system |
US6150921A (en) | 1996-10-17 | 2000-11-21 | Pinpoint Corporation | Article tracking system |
US6812824B1 (en) * | 1996-10-17 | 2004-11-02 | Rf Technologies, Inc. | Method and apparatus combining a tracking system and a wireless communication system |
US6950009B1 (en) * | 1996-11-29 | 2005-09-27 | X-Cyte, Inc. | Dual mode transmitter/receiver and decoder for RF transponder units |
US6289209B1 (en) | 1996-12-18 | 2001-09-11 | Micron Technology, Inc. | Wireless communication system, radio frequency communications system, wireless communications method, radio frequency communications method |
US6466771B2 (en) * | 1996-12-18 | 2002-10-15 | Micron Technology, Inc. | Wireless communication system, radio frequency communications system, wireless communications method, radio frequency communications method, and backscatter radio frequency communications system |
US6104333A (en) | 1996-12-19 | 2000-08-15 | Micron Technology, Inc. | Methods of processing wireless communication, methods of processing radio frequency communication, and related systems |
US6265963B1 (en) | 1996-12-19 | 2001-07-24 | Micron Technology, Inc. | Methods of processing wireless communication, methods of processing radio frequency communication, and related systems |
US6243012B1 (en) | 1996-12-31 | 2001-06-05 | Lucent Technologies Inc. | Inexpensive modulated backscatter reflector |
US6130623A (en) * | 1996-12-31 | 2000-10-10 | Lucent Technologies Inc. | Encryption for modulated backscatter systems |
US6570487B1 (en) | 1997-01-24 | 2003-05-27 | Axcess Inc. | Distributed tag reader system and method |
US6415439B1 (en) | 1997-02-04 | 2002-07-02 | Microsoft Corporation | Protocol for a wireless control system |
US5988510A (en) | 1997-02-13 | 1999-11-23 | Micron Communications, Inc. | Tamper resistant smart card and method of protecting data in a smart card |
US6097292A (en) | 1997-04-01 | 2000-08-01 | Cubic Corporation | Contactless proximity automated data collection system and method |
US6288629B1 (en) | 1997-05-23 | 2001-09-11 | Intermec Ip Corp. | Method of using write—ok flag for radio frequency (RF) transponders (RF Tags) |
US6185307B1 (en) | 1997-07-16 | 2001-02-06 | Gilbarco Inc. | Cryptography security for remote dispenser transactions |
US6265962B1 (en) | 1997-09-03 | 2001-07-24 | Micron Technology, Inc. | Method for resolving signal collisions between multiple RFID transponders in a field |
US20050060069A1 (en) | 1997-10-22 | 2005-03-17 | Breed David S. | Method and system for controlling a vehicle |
US6784787B1 (en) | 1997-11-14 | 2004-08-31 | Btg International Limited | Identification system |
US6778096B1 (en) | 1997-11-17 | 2004-08-17 | International Business Machines Corporation | Method and apparatus for deploying and tracking computers |
US6216132B1 (en) | 1997-11-20 | 2001-04-10 | International Business Machines Corporation | Method and system for matching consumers to events |
US5966471A (en) | 1997-12-23 | 1999-10-12 | United States Of America | Method of codebook generation for an amplitude-adaptive vector quantization system |
US20090322491A1 (en) | 1998-02-19 | 2009-12-31 | Keystone Technology Solutions, Llc | Method of Addressing Messages and Communications System |
US6226300B1 (en) | 1998-02-19 | 2001-05-01 | Micron Technology, Inc. | Method of addressing messages, and establishing communications using a tree search technique that skips levels |
US7315522B2 (en) | 1998-02-19 | 2008-01-01 | Micron Technology, Inc. | Communication methods using slotted replies |
USRE40686E1 (en) | 1998-02-19 | 2009-03-31 | Keystone Technology Solutions, Llc | Method of addressing messages and communications system |
US6307847B1 (en) | 1998-02-19 | 2001-10-23 | Micron Technology, Inc. | Method of addressing messages and communications systems |
US6061344A (en) | 1998-02-19 | 2000-05-09 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6118789A (en) | 1998-02-19 | 2000-09-12 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6307848B1 (en) | 1998-02-19 | 2001-10-23 | Micron Technology, Inc. | Method of addressing messages, method of establishing wireless communications, and communications system |
US6282186B1 (en) | 1998-02-19 | 2001-08-28 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6275476B1 (en) | 1998-02-19 | 2001-08-14 | Micron Technology, Inc. | Method of addressing messages and communications system |
US6072801A (en) | 1998-02-19 | 2000-06-06 | Micron Technology, Inc. | Method of addressing messages, method of establishing wireless communications, and communications system |
US7672260B2 (en) | 1998-02-19 | 2010-03-02 | Keystone Technology Solutions, Llc | Method of addressing messages and communications system |
US6169474B1 (en) | 1998-04-23 | 2001-01-02 | Micron Technology, Inc. | Method of communications in a backscatter system, interrogator, and backscatter communications system |
US6324211B1 (en) | 1998-04-24 | 2001-11-27 | Micron Technology, Inc. | Interrogators communication systems communication methods and methods of processing a communication signal |
US6459726B1 (en) | 1998-04-24 | 2002-10-01 | Micron Technology, Inc. | Backscatter interrogators, communication systems and backscatter communication methods |
US6229987B1 (en) | 1998-05-18 | 2001-05-08 | Micron Technology, Inc. | Method of communications in a backscatter system, interrogator, and backscatter communications system |
US6075973A (en) | 1998-05-18 | 2000-06-13 | Micron Technology, Inc. | Method of communications in a backscatter system, interrogator, and backscatter communications system |
US6192222B1 (en) | 1998-09-03 | 2001-02-20 | Micron Technology, Inc. | Backscatter communication systems, interrogators, methods of communicating in a backscatter system, and backscatter communication methods |
US6566997B1 (en) | 1999-12-03 | 2003-05-20 | Hid Corporation | Interference control method for RFID systems |
US6707376B1 (en) | 2002-08-09 | 2004-03-16 | Sensormatic Electronics Corporation | Pulsed power method for increased read range for a radio frequency identification reader |
US7026935B2 (en) | 2003-11-10 | 2006-04-11 | Impinj, Inc. | Method and apparatus to configure an RFID system to be adaptable to a plurality of environmental conditions |
Non-Patent Citations (28)
Title |
---|
USPTO Transaction History of related U.S. Appl. No. 09/026,043, filed Feb. 19, 1998, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 6,118,789. |
USPTO Transaction History of related U.S. Appl. No. 09/026,045, filed Feb. 19, 1998, entitled "Method of Addressing Messages, Method of Establishing Wireless Communications, and Communications System," now U.S. Appl. No. 6,072,801. |
USPTO Transaction History of related U.S. Appl. No. 09/026,050, filed Feb. 19, 1998, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 6,061,344. |
USPTO Transaction History of related U.S. Appl. No. 09/026,248, filed Feb. 19, 1998, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 6,275,476. |
USPTO Transaction History of related U.S. Appl. No. 09/551,304, filed Apr. 18, 2000, entitled "Method of Addressing Messages and Establishing Communications Using a Tree Search Technique that Skips Levels," now U.S. Appl. No. 6,226,300. |
USPTO Transaction History of related U.S. Appl. No. 09/556,235, filed Apr. 24, 2000, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 6,282,186. |
USPTO Transaction History of related U.S. Appl. No. 09/617,390, filed Jul. 17, 2000, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 6,307,847. |
USPTO Transaction History of related U.S. Appl. No. 09/773,461, filed Jan. 31, 2001, entitled "Method of Addressing Messages, Method of Establishing Wireless Communications, and Communications System," now U.S. Appl. No. 6,307,848. |
USPTO Transaction History of related U.S. Appl. No. 09/820,467, filed Mar. 28, 2001, entitled "Method of Addressing Messages and Communications System," now U.S. Appl. No. 7,315,522. |
USPTO Transaction History of related U.S. Appl. No. 10/652,573, filed Aug. 28, 2003, entitled ,"Method of Addressing Messages and Communications System," now U.S. Appl. No. RE40,686. |
USPTO Transaction History of related U.S. Appl. No. 10/693,696, filed Oct. 23, 2003, entitled "Method and Apparatus to Select Radio Frequency Identification Devices in Accordance with an Arbitration Scheme." |
USPTO Transaction History of related U.S. Appl. No. 10/693,697, filed Oct. 23, 2003, entitled "Method of Addressing Messages, Method of Establishing Wireless Communications, and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/143,395, filed Jun. 1, 2005, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/270,204, filed Nov. 8, 2005, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/416,846, filed May 2, 2006, entitled "Method and Apparatus for an Arbitration Scheme for Radio Frequency Identification Devices." |
USPTO Transaction History of related U.S. Appl. No. 11/855,855, filed Sep. 14, 2007, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/855,860, filed Sep. 14, 2007, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/859,360, filed Sep. 21, 2007, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/859,364, filed Sep. 21, 2007, entitled "Communications Systems for Radio Frequency Identification (RFID)." |
USPTO Transaction History of related U.S. Appl. No. 11/862,121, filed Sep. 26, 2007, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/862,124, filed Sep. 26, 2007, entitled "Method of Addressing Messages and Communications." |
USPTO Transaction History of related U.S. Appl. No. 11/862,130, filed Sep. 26, 2007, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/865,580, filed Oct. 1, 2007, entitled "Method of Addressing Messages, Method of Establishing Wireless Communications, and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 11/865,584, filed Oct. 1, 2007, entitled "Method and Apparatus to Manage Rfid Tags." |
USPTO Transaction History of related U.S. Appl. No. 12/493,542, filed Jun. 29, 2009, entitled "Method of Addressing Messages, Method and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 12/541,882, filed Aug. 14, 2009, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 12/556,530, filed Sep. 9, 2009, entitled "Method of Addressing Messages and Communications System." |
USPTO Transaction History of related U.S. Appl. No. 12/604,329, filed Oct. 22, 2009, entitled "Method of Addressing Messages, Method of Establishing Wireless Communications and Communications System." |
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US8645222B1 (en) | 2009-03-20 | 2014-02-04 | Jpmorgan Chase Bank, N.A. | System and methods for mobile ordering and payment |
US9230259B1 (en) | 2009-03-20 | 2016-01-05 | Jpmorgan Chase Bank, N.A. | Systems and methods for mobile ordering and payment |
US9886706B2 (en) | 2009-03-20 | 2018-02-06 | Jpmorgan Chase Bank, N.A. | Systems and methods for mobile ordering and payment |
Also Published As
Publication number | Publication date |
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USRE41471E1 (en) | 2010-08-03 |
US6061344A (en) | 2000-05-09 |
US6282186B1 (en) | 2001-08-28 |
USRE40686E1 (en) | 2009-03-31 |
USRE41352E1 (en) | 2010-05-25 |
USRE42254E1 (en) | 2011-03-29 |
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