JP2019075818A - Time slot communication system - Google Patents

Abstract

To provide a system that keeps synchronized wireless tags in sleep as long as possible in order to achieve the longest possible life and operate only when absolutely necessary for data transmission with a communication station in the shortest possible active period.SOLUTION: In a system 1, communication stations 3, 4 each emit a synchronization data signal including a time slot symbol for the current time slot. When the states of wireless tags 7 to 14 are switched from a sleep state to an active state at a wakeup time and receive the synchronization data signal in the active state, and the received time slot symbol displays the time slot designated for each wireless tag, a new wakeup time corresponding to the next appearance of the designated time slot is defined in the subsequent time slot cycle to the current time slot cycle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a communication system with a wireless tag.

  The system mentioned at the beginning is known, for example, from DE 4439074 A1. According to this document, at the time of transmission of the preamble, all the radio tags have to be active in order to enable simultaneous data transmission to the radio tags in the classified period. This procedure is less energy efficient or system efficient. Furthermore, in WO 2010/004349 A1, a system is known in which radio tags of individual time slots are classified. This causes the preamble to be emitted in order to synchronize with the communication station. This preamble contains more data packets that indicate the error with respect to the reference time for synchronization between the communication station and the wireless tag. The wireless tag goes from sleep state to active state, to a time defined by the internal time base and within a period of appearance of the preamble, where it receives one of the data packets. In order to adjust the next wakeup time anew and thus maintain synchronization with the communication station, the radio tag takes advantage of the data packet received each time and the error of the reference time encoded therein. , The internal time base is corrected. However, the next preamble for use has proved to be disadvantageous as it causes relatively high total data.

DE4439074A1 WO 2010/004349 A1

  The present invention addresses the task of providing a system in which the problems initially discussed are avoided.

  This task is solved by the system according to claim 1.

  Therefore, the object of the present invention is a system, in which a plurality of time slots are provided for communication per repeated time slot cycle, and a unique time slot symbol is attached to each time slot. A system comprising a communication station for communicating with a plurality of radio tags using a slot communication method, said communication station emitting synchronization data signals including its time slot symbol for the current time slot The wireless tag is configured to switch from sleep state to active state at wakeup time, receive a synchronized data signal in active state, and the received time slot symbol is assigned to the wireless tag in the time slot designated. To display the current time slot cycle following Im slot cycle, is configured to define a new wake-up time corresponding to the next occurrence of the time slot that is specified, a system.

  The procedure according to the invention simultaneously exhibits the advantage that the synchronization between the communication station and the radio tag is recognized and maintained and ensured during operation of the system in the simplest possible way and nevertheless in the most robust way . Unlike the known procedure, here it is no longer necessary for all the radio tags to be active at the same time as the specified time in order to remain synchronized with the time scan of the time slot communication method defined by the communication station. Absent. Similarly, regarding processing of this data and also regarding the total amount of data at the time of communication with the communication station, it has been found that the reception and evaluation of data notifying a temporal error from the reference time can be omitted, which is very expensive. The According to the present invention, each wireless tag participating in communication with the communication station may be notified via a time slot symbol indicating a designated time slot for notification. Therefore, each of the wireless tags individually corresponds to the appearance of a time slot symbol that is important for the notification, identifies the time slot symbol that is important for the notification, and uses its next wake up time. Define at the timing of the time slot communication method set by the communication station. Thereby, it is completely sufficient for the time slot symbol to uniquely identify each time slot, for example using individual time slot identification signals for each time slot. In order to synchronize the communication station and the wireless tag, no further information is necessary, which is coded in the synchronization data signal as well as described for the known procedure. The radio tag appears alone at the time expected by the radio tag or at its expected period, and indicates the time slot designated for the radio tag, depending on the identification status of the time slot symbol, alone with the communication station. Check the synchronization status of.

  The time slot communication method in which the next wake-up time is automatically known to the wireless tag when the wireless tag switches to the sleep state again after confirming the synchronization state as described above. It is basically sufficient because it is known for time scanning. Thus, the definition of a new wakeup time is achieved by a new initiation of the wireless tag, for example a time manipulation stage (eg timer), with the timing parameters already used to switch from sleep to active state. It is limited. The wireless tag then switches back to sleep where it is activated by time operation and stays up again until wakeup and switching from sleep to active state is performed at the new wakeup time at the next time slot cycle. . However, the wireless tag does not have to stay in the sleep state for the rest of the time slot specified for it, but can also process additional tasks in the active state during the time slot or during the time slot cycle. . Also, the time manipulations described so far operate in the background independently of other activities. The definition of a new wakeup time is realized by specifying an absolute or relative time task, for example, relative to the time of appearance of the synchronization data signal or, after an active state, further sleep until that time Relative to such time as taking the state, or relative to time such that the end of the synchronization data signal occurs up to that time. However, the definition of the new wakeup time may be that the time slot symbol is received, the duration of the following sleep state after the active state, or the sum of the sleep and active states, or various such states. The sum of the column durations can also be interpreted as specifying a new wakeup time. Since each wireless tag operates its own time manipulation stage and the exemplary variation in movement of each electronic component is not eliminated, a new wakeup time definition exists for each wireless tag individually, its time It can also include base drift. For this purpose, for example, in a radio tag, the time difference between the expected appearance and the actual appearance of a synchronization data signal having a time slot symbol indicating a time slot designated for each radio tag is measured, The timing of the occurrence is evaluated by a time manipulation stage for correction. However, the compensation is only used in the confirmed synchronization state. However, if another time slot symbol is received at the expected time slot symbol position, there is no synchronization condition and the radio tag has to perform a new synchronization which is subsequently taken up further.

  In the time slot communication method, m time slots, for example, 255 time slots are used, for example, within n seconds, for example, 15 seconds. Therefore, in this time slot communication method, m time slots within one time slot cycle for one communication are used using the wireless tag. Each of the wireless tags can be classified into one of the time slots, where more wireless tags can also be classified into designated time slots.

  Basically, one wireless tag has one wireless communication stage, also called a transceiver, and a logic stage associated therewith. The logic stage can, for example, be realized entirely by hardware or by one microcontroller and one microcontroller with storage elements or integrated storage elements, which storage elements , The stored software is operational. One tag can receive a radio signal using its radio communication stage, can process received data contained in the radio signal using a logic stage, and can sometimes generate reply data using a logic stage, Also, it is emitted again as a wireless signal via the wireless communication stage. The wireless communication stage comprises means for wireless communication and means for converting an analog signal to a digital signal or vice versa.

  Such a wireless tag can have an energy storage element, such as a battery or a solar panel coupled with a rechargeable battery, for its energy supply. In order to operate at maximum energy efficiency, the wireless tag has several operating states. One wireless tag has relatively high energy consumption when active. The active state exists when transmitting and receiving data, updating the display, measuring the battery voltage, and the like. On the other hand, in the sleep state, energy consumption is relatively low. Preferably, as many electronic components as possible are operated in a mode in which the current supply is disconnected or dimmed or at least as little energy requirement as possible. The active state has a time slot primarily for communication with the communication station designated for the wireless tag. In the active state, the wireless tag has, for example, readiness to receive commands and possibly received data from the communication station, and for processing with the logic stage. In the active state, logic stages can also be used to generate transmit data and communicate with the communication station. Outside of the time slot designated for the wireless tag, the wireless tag is mainly operated in a sleep state to save energy. In the sleep state, the logic stage or time manipulation stage only performs the activities necessary for the timing for wakeup at the right time, whereby the wireless tag is for receiving the synchronization data signal and / or Or, for communication with the communication station, the next time slot designated for the wireless tag is ready. To operate with high energy efficiency and thereby achieve the longest possible lifetime of the wireless tag, keep the synchronized wireless tag in the sleep state as long as possible, and the data with the communication station in the shortest possible active period There is a basic driving strategy of driving only when absolutely necessary for transmission.

  The communication station can be as an autonomous device with server functionality. Preferably, the communication station combines a disconnection site between, for example, a cabled communication with an information processing device (e.g. a server) and a wireless communication without a cable using a wireless tag.

  In order to freely use the communication with the communication station, the wireless tag is first registered or classified by the communication station.

  Further, particularly preferred forms and further configurations of the present invention will become apparent from the dependent claims as well as the following description.

  Not only can the synchronization state between the communication station and the wireless tag can be ensured in a simple manner using the measures according to the invention, but the wireless tag that has entered the asynchronous state is again free of the time slot communication method. The temporal diagram can be reverted and hence resynchronized. For this purpose, such an asynchronous radio tag does not switch periodically, as it is when it is in synchronization, for example, from its sleep state to its active state at any time. Switch and stay active in preparation for reception. For example, if nothing is received for a specified period, such as a time slot period, then it will sleep again and repeat the reception attempt until another time. As soon as the synchronization data signal is received, the time slot symbol is exploited. Thereby, the received time slot symbol represents the non-designated time slot with the highest probability, which is confirmed autonomously by the radio tag. The wireless tag knows the system of the appearance of time slot symbols, and according to the evaluation of the received time slot symbol, either in the existing time slot cycle (first time) or in the next time slot cycle For the first time (second time), decide voluntarily whether it can anticipate the designated time slot. In the first case, the wireless tag is configured to define one of the currently existing time slot cycles up to the next appearance of the corresponding new wakeup time slot designated for it. The radio tag verifies that the specified time slot will still appear in the currently existing time slot cycle, by evaluation of the received time slot symbol and by knowledge of the system of appearance of the time slot symbol . In the second case, the radio tag will define one in the time slot cycle following the currently existing time slot cycle to the next occurrence of the corresponding new wakeup time slot specified for it. Configured Since the radio tag has already appeared in the past in this time slot cycle, the designated time slot currently exists because of the evaluation of the received time slot symbol and the knowledge of the system of appearance of the time slot symbol. Make sure that it will no longer appear in the time slot cycle. As described in the introduction at the beginning of the synchronization situation, also for this new wakeup time definition technique, the above-mentioned time manipulation is used, where that time manipulation is operated with timing parameters and with that parameter to synchronization situation The desired start of is achieved. The timing parameters to be selected are derived from the inherent knowledge for the use of the next time slot communication method for the wireless tag, hence the parameters are specified by the logic stage.

  The definition of the correct wakeup time for each wireless tag is performed by the wireless tag based on knowledge of time slot communication method parameters. This parameter may be examined by the radio tag or transmitted thereto upon its registration of the communication station, or may already be programmed into the radio tag in advance. In either case, the wireless tag has a storage stage for storage of parameters of the time slot communication method, and the wireless tag is such that it accesses and evaluates this parameter for the definition of a new wakeup time. If configured, it serves the purpose. This parameter can present all the details of the timing of the time slot communication method, for example, parameters related to the passage of time for communication between the communication station and the radio tag, a predefined time or time interval Parameters related to the basic structure of the time slot communication method, for example, the total number of time slots, duration of time slots, duration of time slot cycle, or details for confirmation of a single time slot A time slot symbol or a parameter related to an algorithm for calculating the time slot symbol. With this parameter, an asynchronous radio tag can, based on the time slot symbol just received, whether the specified time slot can still be expected inside the currently existing time slot cycle or the specified time It can be easily determined autonomously and automatically whether the slot is already known to be in the past and hence the next designated time slot will appear in the next time slot cycle. The wireless tag concerned calculates a new wakeup time in the active state, switches to the sleep state, switches to the active state at the calculated wakeup time, receives the time slot symbol of the designated time slot, and then synchronizes again. Become. In order to receive the synchronization data signal in the designated time slot, the radio tag is first again activated in the next time slot cycle, unless further activity from that is expected in the existing time slot. Switch to

  According to a further aspect of the invention, the wireless tag has a storage stage for storage of a presentation of time slot symbols indicating a designated time slot.

  Both storage stages (storage stage for storage of parameters and storage stage for storage of presentations) can be realized by a single storage chip or by different storage chips. Both storage stages can be incorporated into this storage chip on different storage areas and can follow different access rights. However, both storage stages can also be realized with different storage elements based on safety technology considerations.

  It is clear that it would be advantageous to configure the presentation of the time slot symbol using the hardware address of the wireless tag that uniquely identifies the wireless tag and to program it unchanged in the second storage stage. This ensures that unwanted spurious manipulation of the wireless tag is avoided. Since each wireless tag has one unique hardware address, it is possible to create a strict and non-intrusive graphical classification for one time slot.

  Particularly preferably, the presentation of the time slot symbol mentioned above is realized by the least significant bit or least significant byte of the hardware address, wherein this group of bits used is at least present in the time slot cycle It is necessary to make the total number of time slots copyable. Thus, for example, for the 256 time slots, only the least significant 8 bits or the least significant 1 byte of the hardware address, and for the 128 time slots, only the least significant 7 bits are required. It is. In this context it is advantageous if the total number of time slots corresponds to a power of two.

  The presentation of the time slot symbol or the time slot symbol itself may also consist of the hardware address described above and other numbers programmed.

  The wireless tag is configured to check if the time slot symbols known at the time of reception of the synchronization data signal match it respectively. Verification can be performed, for example, using an algorithm that provides the results of the verification to the processor of the wireless tag upon activation of software that describes the algorithm. The algorithm may, for example, convert from received time slot symbols to a presentation known to the wireless tag, and then compare. However, the wireless tag can also convert from the presentation known to the wireless tag back to the expected time slot symbol, and then the received time slot symbol to the expected time It can also be compared to the slot symbol. However, since this is a very quick and relatively low energy requirement up to the processor level by a simple registration comparison, it is advantageous to simply compare the two or binary coded symbols .

  Basically, for each time slot, an unambiguous, confirmation for use can be made, which has been previously defined in the system. However, it is particularly preferred that the communication station be arranged to generate the time slot symbol as a sequential number (also "slot ID") of each time slot, in response to the appearance of the order of time slots in the time slot cycle. preferable. Therefore, in each time slot cycle, the number 1 is classified into the first time slot, the number 2 into the second time slot, and so on. By providing minimal data traffic also in the data transmission from the communication station to the wireless tag, time slot symbols can be generated in the simplest possible way, avoiding costly algorithms. Only one data packet used for synchronization needs to be transmitted. Thus, the data volume of the transmission of certain time slot symbols for use, per whole, per time slot or per time slot cycle is also less affected. Thus, the channel registration is optimized since the total number of data packets per timeslot or timeslot cycle required for synchronization is as small as possible. The total amount of time slots that occur in the time slot cycle is necessary for the generation of each number of time slots, which ultimately determines the total amount of bits that make up the data packets necessary for synchronization. Since each bit represents two states, it is advantageous if the total number of time slots per time slot cycle is a power of two. Therefore, the time period for reception of the time slot symbol can also be shortened accordingly, which works in favor of the energy balance of the radio tag. Then, in particular, if the hardware address part as presentation of the time slot symbol known to the wireless tag is used on the side of the wireless tag, the received time slot symbol matches the stored time slot symbol. The confirmation of can be done quickly and easily. The radio tag synchronizes with the communication station or with the time scan of the time slot communication method defined thereby in a simple way based on the number of time slots.

  Basically, the synchronization data signal can be configured exclusively via time slot symbols, for example a command for the transmission of commands from the address data or synchronization data signal for tag addressing. Additional communication parameters, such as data, necessary for communication between the communication station and the wireless tag can be excluded. As discussed above, time slot symbols are a very compact indicator for synchronization of communications in the system, so it is conceivable to embed more information in the synchronization data signal in addition to the time slot symbols, We will discuss this later.

  Therefore, according to a further aspect of the present invention, the communication station is configured to embed address data in the synchronization data signal, using it, a plurality per time slot designated for said radio tag The wireless tag evaluates the synchronization data signal with respect to the included address data, if the wireless tag is individually addressed and the time slot symbol received indicates the designated time slot, and It is configured to check if the wireless tags are individually addressed.

  Similar to the use of the RFID tag's hardware address in conjunction with the time slot symbol, the RFID tag hardware address in which the communication station uniquely identifies the RFID tag, in particular omitting the least significant bit or least significant byte. It is also advantageous to configure the address data to be generated using one or more bits or bytes of. Therefore, in the existing system, the hardware address of the wireless tag for unique address processing of each wireless tag is used. On the one hand, which time slot for a wireless tag is specified is defined by the least significant bit or least significant byte. Thus, in order to keep this time slot synchronously and to be individually addressable in this time slot, a relatively large number of wireless tags can be placed in only one time slot, Be classified correctly. Here, the additional bits or bytes of the individual hardware address of this radio tag are used to carry out the individual addressing of the special radio tag. Moreover, the associated radio tag, which is just in the active state to receive the time slot symbol, does not have to switch to the sleep state during that time, but in the existing time slot to check if the address data is present, This procedure represents a significant contribution to system efficiency, as it is necessary to switch back to the active state at a later time. More precisely, it becomes clear whether the radio tag is addressed to all radio tags which simultaneously try to hear the synchronization data signal in this relatively short phase of the active state.

  As described for the embedding of address data, when the communication station is configured to embed command data in the synchronization data signal, there is a further significant contribution for system efficiency, which is used to The command can be sent on the radio tag of the time slot designated for the tag, and the radio tag synchronizes with respect to the included command data when the received time slot symbol announces the designated time slot It is configured to evaluate the data signal and to execute the command. Thus, for example, without individually addressing, commands can be sent to all RFID tags embedded in a designated time slot that are executed by a relatively large group of RFID tags.

  Basically, the wireless tag can also perform standardized (pre-defined) tasks with the identification of the individual address processes, without the need for receiving explicit commands. However, address data for addressing individual RFID tags and command data for sending commands on this individual RFID tag are transmitted so that the RFID tag evaluates the command data and executes the command. It can be seen that it is particularly preferable if the wireless tags are individually addressed using address data. Thus, commands are often sent for individual wireless tags, sometimes in relatively large groups of wireless tags.

  According to a further aspect of the system, the wireless tag executes the command as a single time slot command and terminates the command executed within only one time slot in which the command was received. It is advantageous to be configured. This allows for quick and compact handling of requests as offered to the wireless tag via the communication station. Such a single time slot command can be, for example, a so-called "PING" command, with which it can be determined whether a specified time slot exists or, for example, from one storage page or site to another. It is only checked if there are internal processing commands that cause as little outgoing data traffic as possible, such as a save command for a save page or a switch to a site. The storage page is a logic area (one address area) in which data for one image or the like is arranged or stored in the storage element. In some cases, internal processing of data is performed instead of transmitting data for processing by the wireless tag (for example, data for performing display using a display, etc.) to the wireless tag using a single time slot command Transmit only commands or commands instructing the wireless tag to transmit information to the communication station.

  Relatedly, the wireless tag may be configured to generate confirmation data and to transmit confirmation data in each time slot in which the command is received at the end of the executed command. It is advantageous. Thus, furthermore, the data traffic generated by the confirmation remains confined to each time slot in which the command is transmitted. The next time slot remains unloaded according to the data, which favors system capacity.

  Further, the wireless tag may be configured to transmit confirmation data of a first portion of the time slot (eg, a first of a half or a first of a third), This first part does not touch the second part of the time slot following it, which is located next in time in the synchronization data signal and before the appearance of the synchronization data signal of the next time slot. This two division of the structural or temporal time slot is that the verification data often only needs a short transmission, and hence the remaining part of the relevant time slot, ie the second, for further data passage. Consider the situation where the part (eg the second and third of the halves or the second and third of the halves) is used undisturbed.

  The duration of each part of the time slot does not have to be defined with the numerical value set invariant, but it can be derived from the configuration or use of each of the time slots in a dynamic manner Generally stated.

  In the system, for example, 256 time slots during a 15 second time slot cycle, 58.6 milliseconds each, and 2 to 5 trouble free radio tags can be individually addressed per time slot. Individual tasks in a single time slot command can be delegated to it. By imposing a request on several radio tags per time slot, and thus, it is expected that each radio tag will communicate the above mentioned verification data to all the radio tags in the existing time slot, It is advantageous to follow the two arrangement principles. For this purpose, the radio tag has also been verified, in addition to its own address, when addressing some radio tags using address data, it also evaluates those of the other radio tags addressed. It is configured to transmit internal confirmation data of a designated period for transmission of confirmation data at a time corresponding to the order of the group of addressed wireless tags determined by the address. Since the communication station as the requester of the task knows the radio tag to be addressed, transmission of the confirmation data requires only minimal data traffic, which means that the communication station including the arrangement principle This is because it knows exactly which order of confirmation data to be sent in which order and hence also at what time or for a certain period of time.

  Also, the radio tag transmits multi-time slot commands over several time slots in order to transmit a larger amount of data between the communication station and the radio tag, such that the time slot period is not sufficient for the data transmission. It is configured to execute a command. The processing of such commands may occur in adjacently adjacent time slots or indirectly in adjacent time slots. Thus, for example, the component of the command can be the total number of time slots used, the confirmation of the time slots used, or a time slot group. The time slots used can be limited in time slot cycles, but can also be located jumping over several time slot cycles. Such multi-time slot commands relate, for example, to the downloading of larger amounts of data from the communication station and the uploading of such amounts of data to the communication station from the perspective of the wireless tag. Similar to the single time slot command, the multi time slot command also transmits data for processing by the wireless tag (for example, data such as displaying using a display) to the wireless tag, in some cases , And / or transmits a command instructing the wireless tag to receive data or transmit data at a later time. After receipt of the multi-time slot command, the wireless tag may be timed autonomously to switch back to the energy saving sleep state to switch to the active state at the time data transmission takes place. Here, in the frame of data transmission, new command communication, in particular, new address processing of the wireless tag is unnecessary, and this is because the communication station has already taken the data to the wireless tag by transmitting the multi-time slot command. It is because the system of transmission was defined. Therefore, for example, in a wireless tag having a display, the time of address processing of the wireless tag for receiving the data to be notified is completely separated in time from the actual transmission time of the data to be notified. The transmission of the data to be notified can start at the current time or at another time slot. The transmission of data to be notified can be extended over different time slots of a time slot cycle and can be extended over several time slot cycles.

  If the multi-time slot command corresponds to data transmission from the communication station to the radio tag, it is advantageous if the communication station is configured to transmit the entire data distributed in several time slots, Here, one or several data packets are transmitted per time slot as a part of the entire data, and from each time slot a second time slot portion adjacent to the first portion of the time slot is a data transfer Used for In some cases, as in the description for single time slot commands, the second part of the time slot (e.g. 2 minutes) to avoid touching the other or first part of the time slot for other activities. Only the second one of 1) is used. The same applies, mutatis mutandis, to data transmission from the radio tag to the communication station.

  In order to notify the communication partner that processing of a partial task is performed in each time slot in a time slot series necessary for processing of multi time slot commands, each time slot in which the wireless tag executes the multi time slot command It is advantageous if it is configured to generate and send partial confirmation data.

  In a particularly preferred configuration of the system, the wireless tag is configured to transmit partial confirmation data in the aforementioned second part before the end of each time slot following the received data packet. . Thus, the entire data traffic generated by multi-time slot commands is integrated into the second part of the time slot.

  In response to the configuration of the wireless tag included in the system, the communication station is further configured to receive and process confirmation data in a designated reception period. Therefore, during the period corresponding to the first portion of each time slot, confirmation data for a single time slot command is received, and for the period corresponding to the second portion of each time slot, for multi-time slot Confirmation data is received.

  In a preferred form of the present system, the command processing methods described above are combined, so that the communication station is for the time slot designated for the processing of multi-time slot commands performed by the first radio tag. The second wireless tag is addressed using address data, and command data is used to transmit a single time slot command to the second wireless tag. This makes it possible, in addition to the transmission of a larger amount of data between the communication station and the first radio tag, to assign to the second radio tag an activity or task that generates only a small amount of data for communication with the communication device. Make it In this case, data communication with each wireless tag is processed in various parts of each time slot.

  According to a further aspect of the system, the communication station uses the command in the time slot assigned to the wireless tag for a further wake up time that does not correspond to the normal designated time slot of the wireless tag. It is configured to order, so that the radio tag can be used for data transmission with the communication station in a time slot different from the normal time slot of the radio tag in the time slot communication method. ing. In addition to this, the wireless tag is configured to process this command and switch to the active state at the wakeup time forced by the communication station. This action is important if communication with the designated radio tag is being pushed to the communication station with the (highest) priority. Next, the corresponding wireless tag normally synchronizes itself using a time slot symbol indicating a time slot not designated for the wireless tag. After processing the task received in the non-normal time slot, the corresponding radio tag adapts to the normal time slot of the radio tag again, synchronizes itself again, and then prepares to communicate with the communication station in a synchronized state. Is ready.

  In order to be able to look for a communication station independently, the wireless tag may receive synchronization data signals for a period of time cycle, in particular for a period extended in part to that period. It is configured to check a plurality of times, and switch the wireless channel if no synchronized data signal is received, and then execute the acknowledgment again. Since each communication station occupies a different radio channel, the result of the absence of a synchronization data signal with respect to the tag to be retrieved is that there is no communication station for the corresponding radio channel or such communication The station is outside the range of the wireless tag, so other communication stations have to be searched. This method can be continued until a method of communication with the communication station is found and the wireless tag is registered with that station and available in the system.

  The search can be simplified by limiting the search of the synchronized data signal to a group of preset wireless channels, and the search can be simplified, especially when the wireless tag is connected to the communication station. The station has transmitted in advance. This procedure is reasonable for newly integrated wireless tags in the system, and also for already integrated wireless tags that have been moved and disconnected in communication with the communication station as a result of the movement. Especially reasonable. The limitation of known radio channels is a method of energy saving and also to prevent collisions of radio channels mainly taken by other machines, for example, wireless local area networks (drahtloses lokales Netzwerk) Help.

  The communication stations are all available at the start of operation, in particular the radio channels pre-programmed into the operation of the communication stations, the respective radio channel being used for the other communication stations or the radio Configured to check if the channel is not in use and to use this radio channel for communication with the radio tag assigned or must be assigned to the communication station if there is such an unused radio channel It is an advantage to install new communication stations in existing systems as easily and automatically as possible. The already indicated radio channel is known by the synchronization data signal of the other communication device appearing on that radio channel.

  The system of the present invention may, for example, be located at spatially different locations and include a plurality of communication stations, each communication station designated by the selection of a radio channel in which a group of radio tags is assigned to the communication stations. it can. Thus, it is possible to manage groups of wireless tags in the system in a simple and robust manner, and for each group of wireless tags, the same time slot communication method is used on channels that are different depending on the group.

  In a preferred form of the system, the wireless tag has a display unit for showing an image, the image being structured from image planes, each image plane being represented by image plane data, the wireless tag being an image plane It is configured to combine the individual reception of data and the images by overlaying the image planes, the communication station being configured for transmission of each image plane data across time slots using wireless tags . The advantage with this procedure is that only the image plane where the change occurs need to be selectively transmitted from the communication station to the radio tag. Since the amount of data which has to be transmitted is relatively small compared to the amount of data which has to be transmitted in the case of full image content, the above-described procedure contributes considerably to system efficiency and energy efficiency. Furthermore, the compression of the image data of each image plane that must be transmitted can be optimized, so it is possible to minimize the amount of data that must be transmitted. This is possible because there are usually large "white" or "transparent" parts at the image plane, where very high compression rates are achieved, if they must be transmitted. Thus, as the amount of data that must be transmitted to perform the image update is reduced to a minimum, this procedure is kept low through activities that consume as little energy as possible or energy consumption of the wireless tag, Very beneficially affects the lifetime of the wireless tag.

  In this situation, the wireless tag is configured to modify an existing image by receiving at least one new image plane of the image and replacing the existing image plane of the image with the image plane just received at that time. sell. In this case, the above-mentioned command can be used. In this way, for example, the image data of the corresponding image plane is stored in a new memory page in the wireless tag, and the download of the image data of the image plane is processed from the communication station to the wireless tag using the multitime slot command It can be done. After the download is complete, you can single-time from the other memory page previously used to create the image plane to the new memory page to use the image plane to combine the image with other image planes. It can be switched by slot command.

  According to a preferred embodiment, the wireless tag is configured for the processing of an image in which the image plane has the following meaning: first or second frequency of change of the image content; the first of the image content Or second color; first or second information category of the image content. Thus, an implementation suitable for each field of use of the system can be realized, where a combination of planar meanings is also possible. Also, the image plane can be more than two, for example three, four or five image planes.

  According to such a preferred embodiment, the system implements an electronic price display system, and the display unit of the wireless tag can be used to display product information or price information.

  In each case where a display unit is used, that display unit is also realized, for example, using LCD technology, preferably also electronic ink technology (also called E-Ink, which is synonymous with electronic paper) Is possible.

  According to a further aspect of the system, the wireless tag is configured to perform the switching from sleep state to active state at a wake up time having a lead time prior to the appearance of the synchronization data signal. This measure may mean that the whole of the radio tag, in other words all the parts of the radio tag which are necessary for reception and processing of the synchronization data signal, are fully operational and therefore can not be evaluated significantly Ensure that partial reception of high synchronization data signals is avoided.

  In this case, the lead time period can be selected to be the first fraction of the time slot period of the time slot. The lead time may, for example, be between 0.1% and 10% of the duration of the time slot.

  According to a further aspect of the system, the wireless tag is configured to enter an active state during a reception period longer than the transmission period of the synchronization data signal. The advantage associated with this procedure is that it is ensured that the entire synchronization data signal can be reliably received. The reception period to be used at present can be set as fixed in synchronization with each reception method. However, based on the drift of the time base of the RFID tag confirmed on the basis of the appearance of the synchronization data signal, the period of active state dynamically adjusts to each drift, possibly including the lead time mentioned above It is also possible. The reception period can also be limited by the detection of the loss of the synchronization data signal.

  In order to guarantee optimized reception conditions, in such a system the radio tag maintains the active state entered for the reception of the synchronization data signal, including the tracking period after the reception of the synchronization data signal. It is also possible to be configured. This tracking period may, for example, be defined at a predetermined period of the active state or be possibly dynamically adapted to the current drift or reception state.

  In this case, the period of the follow-up period can be selected such that the follow-up period is the second fraction of the time slot period. The duration of the tracking period may, for example, be between 0.1% and 10% of the duration of the time slot. The duration of the tracking period may coincide with or differ from the duration of the lead time.

  It has proved particularly advantageous that the communication station is arranged to transmit a synchronization data signal at the beginning of each time slot. This procedure allows the start of the time slot to be identified very accurately for the wireless tag, and the correction of the internal time base of the wireless tag can no longer be performed at the start of the time slot And, thus, that all further tasks of the radio tag can proceed with as good synchronization as possible with respect to the time base of the communication station during each time slot, and the remaining total length of the time slots is the above-mentioned further task Ensure that it is ready to be used.

  The communication station is configured to embed in the synchronization data signal a verification period data used to enable the verification time of the verification data of the wireless tag to be set during the time slot; The fact that the wireless tag is configured to transmit confirmation data at a designated time has proved to be advantageous with regard to the systematic and flexible communication method as far as possible between the communication station and the wireless tag. This is particularly advantageous when a plurality of radio tags are addressed in one time slot and each radio tag is informed of a specific confirmation time. Then, each wireless tag can execute a command, for example, after receiving the synchronization data signal, switch to the energy saving sleep state, and switch to the active state again only at the individually determined confirmation time for the wireless tag. The wireless tag verification data can be transmitted, and then switched back to sleep as soon as possible. Therefore, the determination of the confirmation time made in the synchronization data signal is a treatment to improve the energy efficiency of the wireless tag and a procedure for avoiding the assault, and therefore, has a lasting effect on the lifetime of the wireless tag. The confirmation item data may measure absolute time from the beginning of the time slot to indicate absolute time in that time slot, or, for example, may indicate a dwell period of sleep state with respect to previous events, such as previous events, for example , The end of the synchronization data signal, which can be confirmed in the case of a wireless tag, or the end of the active state.

  A further aspect of the invention relates to the assignment of multiple radio tags to multiple communication stations. In order to obtain as balanced a distribution as possible for the allocation of radio tags and communication stations, the data processing device, eg server, is arranged to determine which radio tags may be connected to which communication stations It turned out to be advantageous. The basis for this decision may be the existing distribution of connections in the system, which distribution has to be optimized in terms of the newly added wireless tag. However, there may be fixed and set connection patterns defined and realized in advance.

  The fact that the data processing device, for example the server, is configured to make the wireless tag terminate the existing connection with the communication station and to connect to the other communication station makes the system as dynamic as possible. It can be advantageous. In this case, the server responds to the unbalanced distribution of wireless tags and positively changes the assignment of wireless tags and communication stations in order to realize optimized load balancing. can do.

  This and further aspects of the invention will be apparent from the drawings described below.

The present invention will hereinafter be described in more detail based on the embodiments with the attached drawings, but is not limited to the embodiments. Here, in the respective drawings, the same members are denoted by the same reference numerals. The following is shown schematically in the drawings:
Figure 1 shows the system of the invention; Figure 2 shows the distribution of the radio channel of the system; FIG. 3 shows a block diagram of the electronic price display board; Figure 4 shows an assembly of the images; Figure 5 shows a first state diagram; FIG. 6A shows a second state diagram; FIG. 6B shows a first data structure; FIG. 7A shows a second state diagram; FIG. 7B shows a second data structure; FIG. 8A shows a third state diagram; FIG. 8B shows a third data structure. FIG. 8C shows a fourth data structure.

  FIG. 1 shows an electronic price display system installed in a retail company's building as a system 1 of the present invention for communication according to a time slot communication method. For the sake of clarity, the drawings omitted the display of the buildings and their furnishings. The system 1 includes a server 2, first and second communication stations 3 and 4 (abbreviated as stations hereinafter) and eight wireless tags 7-14 (abbreviated below as ESL representing Electronic Shelf Label). Including. The server is located in the office and connected to stations 3 and 4 via a wired communication circuit (LAN) L. Stations 3 and 4 are connected to ESL 7-13 by radio signals. Stations 3 and 4 are attached to various parts of the ceiling in the room for sale. The ESL 7-14 is attached to the shelf corresponding to the product whose price and product information is displayed using the ESL 7-14. Merchandise information is transmitted from the server 2 to the stations 3 and 4 and transmitted individually from the stations 3 and 4 to each ESL 7-14.

  Each station 3, 4 covers one radio area respectively, and the first radio area boundary of station 3 and the second radio area boundary 6 of station 4 are shown schematically in FIG. In this wireless area, there is an overlapping area in which ESL 9-11 is arranged.

  At the start of operation of the system, stations 3 and 4 were started one after another. Each station 3 or 4 knows the radio channel with channel numbers 3, 5, 8, 9, 10, which is prioritized for the operation of the system 1. This is illustrated in FIG. 2 where the various frequency bands 15-22 are represented by channel numbers K. The conventional WLAN operation can use the frequency bands 15, 16, 17. The frequency bands 18, 19 and 20-22 given priority to the operation of the system 1 correspond to the channel numbers 3, 5 and 8-10 and do not overlap with the frequency band 15-17 of the WLAN. Station 3 automatically selected its radio channel 3 as it was first checked as to whether the radio channel with channel number 3 was already used by another station. Since the radio channel having channel number 3 was already used at the time of confirmation of the vacant radio channel and one having channel number 5 was identified as the next vacant radio channel, station 4 is used as the channel. The radio channel with number 5 was automatically selected. However, the assignment of wireless channels can also be fixed.

  As soon as the stations 3 or 4 are put in the respective radio areas, the ESL 7-14 confirms that the radio signals of the corresponding stations 3 or 4 are present in one or more radio channels. The ESLs 7 and 8 connect to the first station 3. The ESL 12-14 connects to the second station 4. For the ESLs 9-11, it is verified that each station 3 and 4 is available to them. At this time, each ESL 9-11 confirms the reception quality of the radio signal received by each of the stations 3 and 4, and decides the station 3 or 4 which has confirmed the best reception quality. This is to establish a connection with the station 3 or 4 that has confirmed the best reception quality in each radio channel (channel number 3 or 5). However, this decision-making process may be performed at stations 3 and 4, in which case stations 3 and 4 verify each received quality of communication with ESL 9-11 and communicate for each ESL 9-11. As the situation is more favorable, it communicates with each other which of the stations 3 and 4 connect to which of the ESLs 9-11. However, since the server 2 is connected to the stations 3 and 4, the decision on the assignment between the ESL 9-11 and the stations 3 and 4 can be transferred to the server 2. Therefore, within the frame of connection establishment between the respective ESLs 7-14, a radio channel is first selected (also referred to as "channel scan"), and in some cases, the reception quality in each radio channel is evaluated The unique hardware address of ESL 7-14 is transmitted to the stations 3, 4 selected for communication. As a result, each station 3, 4 knows the ESL 7-14 assigned to it. This first assignment between stations 3, 4 and ESL 7-14 is transmitted to server 2.

  Next, a second assignment between each ESL 7-14 and exactly one item is made. As a result, the server knows the location of the item being shown using the shelving, so which ESL 7-14 is at which shelf and at what location of the shelf in the room of the sale To know).

  FIG. 3 shows a block diagram of ESL 7 as a substitute for ESL 7-14, which is all equally configured for use in the system. ESL 7 is a commodity information realized by a wireless module 24, a processor 25 for data processing, control of operation status and preparation of functions, a memory 26 for storing data and programs, and an electronic ink technology for power saving And a display unit 27 for displaying the The wireless module 24 is used for communication based on wireless communication with the station 3 or 4. In the communication, received data is generated from the received wireless signal and transmitted to the processor 25 or transmitted to the processor 25. The transmitted data is converted into a radio signal. The data stored in memory 26 can be assigned to either processor 25 or display 27. Furthermore, it is up to what memory type (ROM, EEPROM, RAM etc.) the memory 26 is, or how the memory 26 is logically or physically allocated to the processor 25 and / or the display unit 27. It is not distinguishable in the drawings. In the selected figures, indications of connections such as signal or data lines between the functional blocks 24-27 and indications of energy storage (in the case of the present invention, batteries) have been omitted.

  Image data BD for generating an image using the display unit 27, hardware address data HAD for specifying the hardware address of the ESL, and parameter data PD regarding parameter setting of the time slot communication method are stored in the memory 26. In the image data BD, the first image plane of the image is designated by the first plane data ED2, and the second image plane of the image is designated by the second plane data ED2. It has to be mentioned here that further image planes can also be present.

  The hardware address data HAD comprises four bytes B3, B2, B1, B0, B0 being the least significant byte of the hardware address data.

  The processor 25 is used to assemble different plane data ED1 and ED2 into a full image in the ESL7. The first and second plane data ED1 and ED2 correspond to one piece of image information of each pixel. However, “transparent”, “background”, or “background color” is defined as image information specific to both image planes. As a result, a single image plane is superimposed one pixel by one pixel, so that the superposition of the image content at the same coordinates of the pixels of each image plane makes it possible to create an entire image. The image is in bitmap format, but may be in other formats, such as JPG.

  This image formation is schematically shown in FIG. The first image plane 28 represented through the first plane data ED1 basically contains static image information 29 on the item, and this static image information is changed only if the ESL 7 is assigned to another item Be done. The static image information 29 relates to, for example, an explanatory text related to a product. All other image parts are defined as "transparent". The second image plane 30 represented through the second plane data ED2 is basically dynamic image information 31 which changes relatively frequently, eg daily, several times daily, or weekly, as compared to static image information. including. The dynamic image information 31 relates, for example, to the price of the product or the validity of the discount, for example, the start date and the end date or other conditions attached to the time or discount. All other image parts are defined as "transparent". The total image 32 represented through the image data BD, formed by overlapping each pixel of the first image plane 28 and the pixels of the second image plane 30 completely corresponding to that pixel, is a static and dynamic image Information 29, 32 and the part marked "transparent" remaining between them are shown.

  In the ESL 7, all field image data BD can be received in a compressed form at one time, decompressed, and stored in the memory 26. This may for example be done for the first transmission of the whole image. However, this method takes a relatively long time, thus causing relatively high energy requirements. As long as the image is present in the ESL 7, partial updating of the image is more efficient as it can be done with energy saving. To that end, the ESL 7 receives each image plane (e.g. the second image plane 30) which has to be updated separately from the other image planes (e.g. the first image plane 28) already placed in the memory 26, It can be decompressed and placed in memory 26. Next, the newly created second plane data ED2 is accessed internally (switched from one memory side to the other memory side) in order to newly form the entire image 32.

  The ESL 7 comprises a time control stage 33 which may be implemented as a separate hardware element or may be at least partially implemented using a processor 25. This time control stage 33 generates a time base typical for ESL and uses this time base to control the state timing (transition and termination) of ESL 7. Control of timing may be performed, for example, using timing parameters that are inherently known and / or provided to the processor.

  In the following, the time slot communication method used for the system 1 will be taken up using FIGS. 5-8. Here, only the ESL 7-9 assigned to the first stage 3 is taken up, but the same description applies to the ESL 11-14 assigned to the second station 4. In the state diagram shown in FIGS. 5-8, the time t is described on the abscissa. On the ordinate, the respective state Z is described for the elements of the system 2 considered in the description. Thus, this figure shows the temporal state progression.

  In each of FIGS. 5-8, the top state progression shows the state of stage 3 labeled ST. During one time slot cycle period DC (for example, 15 seconds), N time slots Z1... Having the same time slot period DS (for example, approximately 58 milliseconds). . . ZN (for example, 256) can be used. Stage 3 is switched between transmit state T and quiescent state R during a time slot cycle period DC. The transmission state T is always time slot Z1. . . At the beginning of ZN, each corresponding time slot symbol ZS1, ZS2,. . . It is held during synchronization data signal period DSD (or transmission period DSD of synchronization data signal SD) to transmit ZSN. Each time slot symbol ZS1. . . As ZSN, each time slot Z1. . . The consecutive numbers of ZN are time slot Z1. . . It is used according to the appearance order of ZN. Thus, in hexadecimal (marked "Hex"), the first time slot Z1 has the time slot symbol Hex 00, the second time slot Z2 the time slot symbol Hex 01, etc. The slot symbol ZN (the 256th time slot Z256 in this example) is marked with the symbol Hex FF.

  The ESL 7-9 is described below in hexadecimal notation (most significant byte = fourth byte B3: third byte B2: second byte B1: least significant byte left: first byte B0 on left) The hardware address of is taken up. The hardware address of the ESL 7-9 is unchanged during the actual operation of the system 1. However, to illustrate the various aspects of system 1 using a predictable number of ESLs, sometimes different hardware addresses are assigned to the ESLs of system 1 according to the drawings, or one or more ESLs are used. Sometimes it can not be included in the explanation.

  In the case of FIG. 5, the hardware address of the first ESL 7 is Hex B 2:00: 01: 00, that of the second ESL 8 is Hex B 2:00: 01: 01, and that of the third ESL 9 is Hex B 2:00: 0 2:00. . The fourth ESL 10 is not considered.

  In the case of FIG. 6, the hardware address of the first ESL 7 is Hex B 2: 00: 01: 00, that of the second ESL 8 is Hex B 2: 00: 02: 00, and that of the third ESL 9 is Hex B 2: 00: 03: 00. . The fourth ESL 10 is not considered.

  In the case of FIG. 7, the hardware address of the first ESL 7 is Hex B 2: 00: 01: 00. The remaining three ESLs 8-10 are not considered.

  In the case of FIG. 8, the hardware address of the first ESL 7 is Hex B 2:00: 01: 00, that of the second ESL 8 is Hex B 2:00: 01: 01, that of the third ESL 9 is Hex B 2:00: 02: 01, The one of 4 ESL 10 is. The fourth ESL 10 is B2: 00: 03: 01.

  In the system 1, using the least significant byte B0, in each ESL 7-9, confirmation of a time slot appearing in the frame of the time slot communication method assigned to each ESL 7-10 is performed. The remaining three bytes B1-B3 of the hardware address, except for the least significant byte B0, are assigned to each ESL in time slot Z1. . . Used to individually address ESL 7-10 in ZN.

  In FIG. 5, the first ESL 7 is in a more synchronized state. The first ESL 7 awakes from the sleep state S at the first wake-up time TA1 and switches to the active state E ready for reception before the appearance of the expected synchronization data signal SD with the elapse of the relatively short lead time DV, Comparison of the received data signal SD during the reception period DE with one time slot symbol ZS1 (Hex 00), with the least significant byte B0 of its hardware address (Hex 00) and the received time slot symbol ZS1 Check that the first time slot Z1 assigned to the first ESL 7 is displayed (match of the byte to compare: hardware address B0 and the first time slot symbol ZS1) and define the new wakeup time The parameters of the time control stage 33 used to control wakeup as , Save for wakeup in the next time slot cycle, enter sleep state S again with relatively short lead time DN, and when the set sleep state residence time is over, a new (second) wakeup as planned At time TA2, this occurs before the new beginning of the first time-strot cycle Z1 by the lead time VD. The same applies to ESLs 8 which are synchronized as well as the first ESL 7.

  The third ESL 9 is desynchronized before the synchronization time TSY, which is only indicated by the dashed arrow 34 parallel to the time axis. The third ESL 9 wakes up at an arbitrarily selected first wakeup time TA1 and switches from the sleep state S to an active discharge operation E ready for reception, and waits in this state until receiving a new appearance of the synchronization data signal SD In this case, the second time slot symbol ZS2 (Hex 01) is received. The third ESL 9 is based on the least significant byte B (Hex 01) of its hardware address, and the time slot assigned to it has already been in the past during the current time slot cycle, and thus the time slot symbol Recognizing that the next time slot with Hex 00 will finally come in the next time slot cycle, then the time slot Z2 just confirmed at that time is one time slot on the side of its original time slot Z1 The separation is calculated, which is referred to below as the time slot difference. Therefore, in the third ESL 9, the time control stage 33 is the same as the ESL in the synchronized state, the read time DV before the appearance of the first time slot Z1 of the next time slot cycle of the new wakeup time TA2 Are programmed to separate The dwell period DSA which has to wait when in the sleep state S is calculated as follows: The time slot period DS is subtracted from the sleep state dwell period (if it is in the synchronized state), time slot Multiply the difference (in this case the value 1). Therefore, the third ESL 9 is in the synchronized state again as only the concept is shown by the continuous line, and after switching from the active state E to the sleep state S, after the dwell period DAS ends, the new wakeup time TA2 To the active state E again.

  Based on FIG. 6A, addressing the ESL 7-9 individually and instructing the ESL 7-9 individually with a single time slot command will be described. Only the first time slot Z1 embedded between the two synchronization data signals SD is shown. Address data AD, command data CD and confirmation time data ZD are embedded by the station 3 in the synchronization data signal SD of the first time slot Z1. The first ESL 7 is based on the address data AD of Hex B 2:00: 01, the second ESL 8 is based on the address data AD of Hex B 2:00: 02, the third ESL 9 is based on the address data of Hex B 2:00: 03 Be done. The command data CD is used to transmit a "PING" command to the first ESL 7, a "PING" command to the second ESL, and a "SWPAG2" command to the third ESL 9. This command is a single time slot command to be processed in such ESL 7-9, spending a little time immediately after being decoded. Using the two "PING" commands described above, it is tested whether the addressed ESL 7, 8 responds with the confirmation data ACD, ie whether the ESL 7, 8 is present or has reacted and synchronized in the first place. For example, to change the image shown using the display unit 27 as described with reference to FIG. 4 using the “SWAPG2” command, the (first) current memory page and the second memory page may be displayed in the third ESL 9 Can be switched to Furthermore, with the synchronization data signal SD, the confirmation time is transmitted by transmitting the first quiescent period DR1 for the first ESL7, the second quiescent period DR2 for the second ESL8, and the second quiescent period DR2 for the third EL9. The reference point of the three stationary periods DR1-DR3 is always the end of the reception period DE. The data configuration transmitted at the beginning of the first time slot Z1 using the synchronization data signal SD is shown in FIG. 6B.

  Instead of a single quiescent period DR1-DR3, the maximum duration of the response resulting from the sum of each quiescent period DR1-DR3 and the period for transmitting the confirmation data ACD may be mentioned.

  According to FIG. 6A, each ESL 7-9 indicates a time slot to which the first time slot symbol Z1 is assigned respectively (in all three ESLs 7-9, the least significant byte B0 of the hardware address is Hex 00). Yes, I recognize that I am in sync. The confirmation of the address data AD indicates that each ESL 7-9 is individually addressed (in the address data AD, there are three remaining bytes B1-B3 of each hardware), which are designated in the respective ESL 7-9. The decoded command is executed immediately after being decoded, and an individual quiescent period DR1. . . After the end of DR3, individual confirmation data ACD are transmitted to station 3 ready to receive confirmation data ACD during station reception period SDE. The complete processing of the single time slot command, including the communication of the confirmation data ACD, takes place during the first part 36 of the time slot Z1, so that the second part 37 has other problems, for example multitime It can be used to process slot commands, which is taken up in detail in FIGS. 7-8.

  FIG. 7A illustrates the processing of multi-time slot commands in which the first ESL 7 has full data over three adjacent time slots Z1-Z3 (eg, all of the images that must be shown, Or, only one image plane of the image), three data packets DAT1. . . It is divided into DAT 3 and received from station 3. The first ESL 7 uses the synchronization data signal SD to recognize the synchronized state of the first ESL 7 and the fact that it is individually addressed (address data Hex B 2:00: 01), and during the time slot Z1-Z3. The above three data packets DAT1. . . Receive and decode the "DATA_INIT" command used to instruct the first ESL7 to receive DAT3 and enter sleep state S at the end of the receive period DE for the first wait period DW1 and its first wait period DW1 is a time slot It ends with the end of the first half of period DS. At the beginning of the second part 37 of the first time slot Z1, the station 3 enters the transmission state T and the first ESL 7 is ready to receive the first data packet DAT1 during the data transmission period DT. Enter the active state E. Thereafter, the first ESL 7 confirms the reception success during the confirmation period DA in which the station 3 is also in the reception state E, using the partial confirmation data ACD1. The confirmation period DA ends before the end of the first time slot Z1. After the confirmation period DA ends, the first ESL 7 remains in the sleep state S during the second standby period DW2 which lasts until the end of the first portion 36 of the second (next) time slot Z2. At the beginning of the second portion 37 of the second time slot Z2, station 3 enters the transmission state T and the first ESL 7 is ready to receive the second data packet DAT2 during the data transmission period DT Active state E is entered. The same applies to the third time slot Z3, the end of which is the end of the data transmission. Each successfully transmitted data packet DAT1-DAT3 is verified using partial validation data ACD1-ACD3. The data structure transmitted at the beginning of the first time slot Z1 using the synchronization data signal SD is shown in FIG. 7B.

  Based on FIG. 8A, data transmission using a combination of one multi-time slot command and three single-time slot commands is described. The first ESL 7 is synchronized (the least significant byte B 0 of the hardware address is Hex 00) and individually addressed (address data Hex B 2:00) using the synchronization data signal SD : 01), and three data packets DAT1.about.3 during time slots Z1-Z3. . . Receive and decode a "DATA_INIT" command used to instruct the first ESL 7 to receive DAT3. The data structure transmitted at the beginning of the first time slot Z1 using the synchronization data signal SD is shown in FIG. 8B. Data transmission from station 3 to the first ESL 7 continues as described in FIG. 7A.

  The second time slot symbol Z2 indicates the time slot specified in ESL 8-10 (the least significant byte B 0 of the hardware address is Hex 01 in all three ESLs 8-10), so the remaining three ESLs 8 -10 recognizes that ESL 8-10 is synchronized at the beginning of the second time slot. As described with respect to FIG. 6A, verification of the address data AD indicates that each ESL 8-10 is individually addressed (in the address data AD there are three remaining bytes B1-B3 of each hardware). ), The command specified for each ESL 8-10 (in this case three “PING” commands) is decoded and then executed immediately, and the individual quiescent period DR1. . . After the end of DR3, individual confirmation data ACD are transmitted to station 3. The data structure transmitted at the beginning of the second time slot Z2 using the synchronization data signal SD is shown in FIG. 8C.

  As can be clearly seen, the first part 36 of the second time slot Z2 for single time slot command and the second part 37 of the second time slot Z2 for multi time slot command are reserved for the data communication required respectively Thus, the three single time slot commands and the one multi time slot command are handled almost simultaneously for the time unit "time slot" in the second time slot T2. However, the assignment of each command type to the portions 36, 37 of the time slot can be reversed.

  Finally, it is to be understood that the drawings described above in detail are merely examples that can be modified in various ways by those skilled in the art without departing from the scope of the present invention. As pointed out for completeness, the use of the indefinite article "ein" or "eine" does not exclude the possibility of multiple corresponding features.

Claims (40)

-A plurality of time slots (Z1-ZN) are provided for communication per one time slot cycle in repeated succession, and each time slot (Z1-ZN) is assigned a unique time slot symbol (ZS1-ZSN) A system (1) including a communication station (3, 4) for communicating with a plurality of wireless tags (7-14) using the time slot communication method described above,
Said communication station is arranged to emit a synchronization data signal (SD) comprising its time slot symbol (Z1-ZN) for the current time slot (Z1-ZN),
-The wireless tag (7-15) is
+ Switch from sleep state (S) to active state (E) at wakeup time (TA1),
+ In the active state (E), receive the synchronization data signal (SD),
+ When the received time slot symbol (ZS1-ZSN) indicates the time slot (Z1-ZN) designated for the wireless tag (7-15), in the subsequent time slot cycle of the current time slot cycle, A system configured to define a new wake up time (TA2) corresponding to the next occurrence of a designated time slot (Z1-ZN).   If the received time slot symbol (ZS1-ZSN) indicates a time slot (Z1-ZN) not designated in the wireless tag (7-14), the wireless tag (7-14) is designated in the designated time slot. If (Z1-ZN) appears in the current time slot cycle, during the current time slot cycle, or if the designated time slot (Z1-ZN) no longer appears in the current time slot cycle The method according to claim 1, wherein during the subsequent time slot cycle of the current time slot cycle, a new wakeup time (TA2) corresponding to the next occurrence of the designated time slot (Z1-ZN) is defined. The system (1) described in 1.   The wireless tag includes a storage stage (26) for storing parameters of the time slot communication method, and the wireless tag (7-14) accesses and evaluates this parameter for the definition of a new wakeup time (TA2) The system (1) according to claim 1 or 2, configured in   The wireless tag (7-14) includes a storage stage (26) for storing an indication of a time slot symbol (ZS1-ZSN) representing a time slot (Z1-ZN) designated for the wireless tag The system (1) according to any one of 1 to 3.   The above indication of the time slot symbol (ZS1-ZSN) is configured using the hardware address of the wireless tag (7-14) uniquely identifying the wireless tag (7-14) and is stored as unchanged The system (1) according to claim 4, wherein the system is programmed in (26).   The system (1) according to claim 5, wherein said indication of a time slot symbol is realized by the least significant bit or least significant byte of said hardware address.   7. The wireless tag according to claim 1, wherein the wireless tag is configured to confirm whether the time slot symbol known by the wireless tag matches the time slot signal at the time of receiving the synchronization data signal. The system (1) described in item 1.   The communication station is configured to generate time slot symbols as successive numbers of each time slot in response to the appearance along the order of time slots in a time slot cycle. The system (1) described in item 1. The communication station (3, 4) is configured to embed the address data (AD) in the synchronization data signal (SD), and using the address data (AD), the wireless tag (7-14) A plurality of wireless tags (7-14) can be individually addressed per one time slot (Z1-ZN) designated in
-The wireless tag (7-14) contains the address when the received time slot symbol (ZS1-ZSN) indicates the time slot (Z1-ZN) designated for the wireless tag (7-14). 9. A method according to claim 1, further comprising: evaluating the synchronization data signal (SD) with respect to the data (AD) and checking whether the corresponding radio tag (7-14) is individually addressed. The system (1) according to any one of the items.   The communication station (3, 4) uniquely identifies the new tag (7-14). One or more bits or bytes (B3, B2, B1) of the hardware address of the wireless tag (7-14). The system (1) according to claim 9, wherein the system (1) is configured to generate address data (AD), using, in particular, omitting the least significant bit or least significant byte (B0). The communication station (3, 4) is configured to embed command data (CD) in the synchronization data signal (SD), and using the command data (CD), the wireless tag (7-14) Command can be sent to one radio tag (7-14) during the time slot (Z1-ZN) specified in
-The wireless tag (7-15) contains a command when the received time slot symbol (ZS1-ZSN) displays the time slot (Z1-ZN) designated for the wireless tag (7-14). 11. A system (1) according to any one of the preceding claims, characterized in that it is arranged to evaluate a synchronization data signal (SD) with respect to data (CD) and to execute a command.   The wireless tag (7-14) evaluates command data (CD) and executes the command when the wireless tag (7-14) is individually addressed using address data (AD) System (1) according to claim 11 when being subordinate to claim 9 or 10.   The wireless tag (7-14) is configured to execute the command as a single time slot command and complete the executed command in only one time slot (Z1-ZN) that has received the command. System (1) according to claim 11 or 12.   -When completing the command being executed, the wireless tag (7-14) generates confirmation data (ACD) in the time slot (Z1-ZN) that received the command and transmits the confirmation data (ACD) System (13) according to claim 13, configured as.   -The radio tag (7-14) is configured to transmit acknowledgment data (ACD) in the first part (36) of the time slot (Z1-ZN), the first part (36) of which is the time Of the subsequent time slot (Z1-ZN) before the appearance of the synchronized data signal (SD) of the next time slot (Z1-ZN), which is positioned subsequent to the synchronous data signal (SD) The system (1) according to claim 14, wherein the two parts (37) are not touched.   -When a plurality of wireless tags (7-14) are addressed using address data (AD), the wireless tag (7-14) is addressed to one or more other than its own address Based on the identified address in the group of the radio tag (7-14) being addressed within the period designated for the evaluation of the radio tag (7-14) and transmission of the confirmation data (ACD) System (1) according to claim 14 or 15, wherein it is arranged to transmit its own confirmation data (ACD) at a time corresponding to its own order determined.   System (1) according to claim 11 or 12, wherein the radio tag (7-14) is configured to execute one command as a multi-time slot command over multiple time slots (Z1-ZN).   The multi-time slot command relates to data transmission from the communication station (3, 4) to the radio tag (7-14),-the communication station (3, 4) has all data in multiple time slots (Z1-ZN) And one data packet (DAT1-DAT3) is transmitted as part of all data per time slot (Z1-ZN), and for each time slot (Z1-ZN), The second part (37) of each time slot (Z1-ZN) adjacent to the first part (36) of each time slot (Z1-ZN) is used for transmission. System (1).   The wireless tag (7-14) is configured to generate and transmit partial confirmation data (ACD1-ACD3) in each time slot (Z1-Z3) in which a multi-time slot command is executed. Or the system according to 18 (1).   The wireless tag (7-14) is partially verified in the second part (37) after the received data packet (DAT1-DAT3) and before the end of each time slot (Z1-ZN) System (1) according to claim 19, when being dependent on claim 18, configured to transmit data (ACD1-ACD3).   The communication station (3, 4) is configured to receive and process confirmation data (ACD; ACD1-ACD3) in the reception period (SDE; DA) specified for it. Or the system (1) according to any one of 19-20.   The communication station (3, 4) uses address data (AD) for the time slot (Z1-ZN) specified by the first radio tag (7-14) for processing of multi-time slot commands The second wireless tag (7-14) is addressed, and a single time slot command is transmitted to the second wireless tag (7-14) using command data (CD). A system (1) according to any one of the claims 16 and 17-21.   The communication station (3, 4) requests the wireless tag (7-14) for its wireless wakeup time which does not coincide with the time slot (Z1-ZN) normally assigned to the wireless tag (7-14). During the time slot (Z1-ZN) specified in the tag (7-14), notification is performed using a command, whereby the wireless tag (7-14) can transmit the normal time slot (7 in time slot communication method). 23. A method according to any one of claims 11 to 22, configured to be used for data transmission with a communication station (3, 4) in a time slot (7-14) different from -14). System (1).   -The radio tag (7-14) checks several times whether it can receive the synchronization data signal (SD) over a period coinciding with the period of the time slot cycle, in particular over an extended period of a part of the period An arrangement according to any one of the preceding claims, characterized in that the radio channel (18, 19, 20-22) is switched if no synchronized data signal (SD) is received and reception confirmation is carried out again. The system (1) described in the section.   -The wireless tag (7-14) communicates the search for the synchronization data signal (SD) with a group of predesignated wireless channels (18, 19, 20-22), in particular the wireless tag (7-14) The system according to claim 1, wherein when connected to the station (3, 4) it is arranged to limit in advance to the radio channel (18, 19, 20-22) transmitted by the communication station (3, 4). 24. System 1 (1) according to any one of up to 24. The communication stations (3, 4) are used at the start of operation, in particular for the respective radio channels (18, 19, 20) for the radio channels (18, 19, 20-22) preprogrammed for operation. 20-20) check if it is used by another communication station (3, 4) or if the radio channel (18, 19, 20-22) is not used,
If there is such an unused radio channel (18, 19, 20-22) that radio channel (18, 19, 20-22) belongs to or should belong to the communication station (3, 4) 26. A system (1) according to any one of the preceding claims, which is adapted to be used for communication with a tag (7-14).   The system (1) has a plurality of communication stations (3, 4), and each communication station (3, 4) has a radio channel (18, 19, 20-22) belonging to the communication station (3, 4) 27. System (1) according to any one of the preceding claims, wherein a group of wireless tags (7-14, 11-14) is assigned by selection of. The wireless tag (7-14) comprises a display unit for the display of the image (32), the image (32) being structured in the image plane (28, 30), each image plane (28, 30) being It is expressed by image plane data (ED1, ED2), and the wireless tags (7-14) receive the image plane data (ED1, ED2) individually and overlap the image planes (28, 39) to form an image. Configured to assemble (32),
The communication station (3, 4) is configured to transmit the respective image plane data (ED1, ED2) in the communication of the whole time slot using the wireless tag (3, 4) 27. The system (1) according to any one of the preceding claims. -Wireless tags (3, 4) are
+ Receive at least one new image plane (28, 30) of the image (32),
+ Replace the existing image plane (28, 30) of the image (32) with the image plane (28, 30) just received to create a new appearance image,
The system (1) according to claim 28, wherein the system (1) is configured to modify an existing image (32). The wireless tag (7-14) has the following meaning on the image plane (28, 30):
-The first or second frequency of change of the image content, or
-The first or second color of the image content, or
-First or second information category of image content,
The system (1) according to claim 28 or 29, wherein the system is configured to change the image (32) given.   The system (1) realizes an electronic price display system, and the display unit (27) of the wireless tag (7-14) is used as a display of product information or price information etc. The system (1) described in.   -The wireless tag (7-14) is switched from the sleep state (S) to the active state (E) at the wakeup time (TA1, TA2) and the lead time (DV) before the appearance of the synchronization data signal (SD). 32. A system (1) according to any one of the preceding claims, wherein the system (1) is arranged to execute using.   System (1) according to claim 32, wherein the lead time (DV) is a first fraction of the time slot duration (DS) of the time slot (Z1-ZN).   The wireless tag (7-14) is configured to enter an active state (E) during a reception period (DE) longer than the transmission period (DSD) of the synchronization data signal (SD). 33. The system (1) according to any one of the preceding claims.   The wireless tag (7-14) uses the tracking period (DN) after the reception of the synchronization data signal (SD), with the active state (E) entered to receive the synchronization data signal (SD) 35. The system (1) according to any one of the preceding claims, which is arranged to continue.   36. The system (1) according to claim 35, wherein the following period (DN) is the second minor part of the time slot period (DS) of the time slot (Z1-ZN).   37. A communication station (3, 4) according to any one of the preceding claims, wherein the communication station (3, 4) is configured to transmit a synchronization data signal (SD) at the beginning of each time slot (Z1-ZN). System (1). -The communication stations (3, 4) are configured to embed the confirmation period data (DR1-DR3) in the synchronization data signal (SD), and use the confirmation period data (DR1-DR3) to wireless tag The confirmation time in the time slot (Z1-ZN) where the confirmation data (ACD) of (7-14) is expected can be determined,
System (1) according to any of the preceding claims, wherein the wireless tag (7-14) is configured to transmit confirmation data (ACD) at said time.   To determine which communication stations (3, 4), wireless tags (7-14) and which wireless tags (7-14) may connect to which communication stations (3, 4) System (1) according to any of the previous claims, comprising a configured information processor (2).   A plurality of communication stations (3, 4), a plurality of wireless tags (7-14), and wireless tags (7-14) terminate the existing connection of the communication stations (3, 4), and the other communication stations ( System (1) according to any of the preceding claims, comprising an information processing device (2) configured to be connected to 3, 4).

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