Abstract: In certain embodiments, a method may include receiving, at one of a plurality of remote units, a command from a control unit. The method may also include determining a random number specifying a time slot of a first series of time slots for transmitting a second data sequence to the control unit, and, in response to a determination that the random number specifies the first time slot in the first series of time slots, determining a new random number. The method may further include transmitting, in the first time slot in the first series of time slots, a first data sequence to the control unit. The method may further include receiving a control signal. The control signal having been transmitted by the control unit upon detection of an at least partially simultaneous transmission of first data sequences by more than one of the remote units.

Abstract: A method includes transmitting, from a base station, a first request and receiving, from a transponder, a first code transmitted responsive to the first request. The method includes transmitting, from the base station, first encoded transmission information comprising a base station code encoded using the first code and a first identification. The base station transmits a second request, and a second code, transmitted by the transponder responsive to receiving the second request and encoded using a base station code extracted from the first encoded transmission information using the first code and the first identification, is received. Second encoded transmission information, including a second identification encoded using the second code, is transmitted from the base station.

Abstract: In certain embodiments, a transponder comprises a transceiver configured to receive a forward link having a forward-link header comprising at least one symbol for configuring a setting of the transponder. The transponder may be configured to transmit a return link having a return-link header comprising information based on one or more characteristics of the transponder, and to receive a modified subsequent symbol of the forward-link header. The modified subsequent symbol of the forward link header generated by analyzing the return-link header to determine adjusted information for configuring the setting of the transponder and modifying the subsequent symbol of the forward-link header in accordance with the adjusted information for configuring the setting of the transponder.

Abstract: In particular embodiments, an error correction during the transmission of the data word is made possible through the change of the modulation state at pre-defined time points.

Abstract: A transponder is provided, in particular a passive and/or backscatter-based transponder, for an RFID system, wherein at least one first piece of information can be stored in a first memory area on the transponder that is accessible in clear text only by a read access internal to the transponder, and a second piece of information can be stored in a second memory area that is accessible in clear text through an air interface for read access, and the second piece of information is generated from the first piece of information using an asymmetric encryption method. The invention further relates to an RFID system for wireless data exchange comprising a transponder and a base station, and a method for requesting write and/or read access to a transponder, in particular a passive and/or backscatter-based transponder.

Abstract: A method for recognizing time-variable functional states, e.g., in the course of a programming process, in RFID systems is disclosed, which includes at least one transponder or remote sensor and at least one base station, which transmits data and/or power to the transponder or sensor by a carrier signal. According to the invention, after a specified process state is attained at least one confirmation symbol is transmitted by the transponder or sensor to the base station. As a result, no unfavorable “worst case” scenario has to be provided for chronologically controlling time-variable processes because the base station is able to clearly recognize the beginning and end of the process, as well as the state thereof. RFID systems or remote sensor systems can thus be controlled more quickly and more reliably, resulting especially in reduced costs.

Abstract: In certain embodiments, an apparatus includes a rectifier and a switch. The rectifier is configured to modulate a received carrier signal. The switch is coupled to at least one node of the rectifier. The switch is configured to modify an impedance of the rectifier to modulate the received carrier signal by providing a potential to the at least one node of the rectifier based on a field strength of the received carrier signal and a modulation-control signal.

Abstract: A method and system for data communication between a base station and at least one transponder via a high-frequency electromagnetic carrier signal onto which information packets are modulated. Each information packet has a header section, a middle section, and a trailer section. The header section can be provided in a forward link of a data communication between the base station and the transponders for controlling data communication. The header section is used in a return link of a data communication in order to transmit information from the transponder to the base station.

Abstract: A method and a device are provided, in particular a transponder, for generating a random number by a linear feedback shift register, wherein a first seed is generated by means of a first automaton, a second seed is generated by means of a second automaton, the first and second automata operate using different functional principles, so that the first and second seeds have different properties, and the shift register is reloaded with the first and/or second seed.

Abstract: A method may include generating by a transponder a first code and transmitting the first code to a base station. The base station may generate first transmission information, encoding a base station code with a first identification and a first random number code, and may transmit the first transmission information to the transponder. The transponder may extract the base station code. A second code may be generated by the transponder and transmitted to the base station upon an associated request from the base station. Before transmission to the base station, the second code may be encoded with the extracted base station code. Second encoded transmission information comprising a second identification may be generated by the base station using the second code and transmitted to the transponder. A memory region of the transponder may be released for read and/or write access after the second identification was verified as valid.

Abstract: A method for communicating between a control unit and a plurality of remote units located in the response area of the control unit is provided. The remote units are prompted to transmit a data sequence to the control unit upon receipt of a command sent by the control unit. The control unit transmits a control signal to the remote units substantially simultaneously with the transmission of the data sequence as a function of a communication state, such as the absence of a transmission of the data sequence by at least one remote unit or an at least partially simultaneous transmission of the data sequence by more than one remote unit. In this way, communication methods can be shortened, in particular in terms of time, without adversely affecting communication reliability.

Abstract: A method for the at least temporary activation of bidirectional communication between a transponder having a nonvolatile memory area and a base station, whereby the transponder in an at least partial mute state receives messages, but no information-related data from the nonvolatile memory area are transmitted and for activation a data stream is transmitted to the transponder by the base station, wherein the data stream for a transmission is linked with a symmetric password, the enable signal is extracted by the transponder with the symmetric password from the received data stream, and the transponder is activated at least temporarily after the enable signal has been verified as valid. The invention relates further to a transponder having means for carrying out this type of procedure.

Abstract: A method for wireless data transmission between a base station and a transponder is provided, whereby a message, comprising at least one command and one data sequence, is transmitted by the base station, the message is received and evaluated by the transponder, at least one key is provided in the transponder after receipt of the command and before complete receipt of the message and the key is transmitted to the base station, the key is detected by the base station, and parts of the message, still to be transmitted, and/or subsequent messages are encoded by the base station with the key.

Abstract: A method for data exchange is provided, whereby a first code is generated by a transponder, which is transmitted to a base station, a first transmission information is generated by the base station by encoding a base station code with a first identification and the first random number code, the first transmission information is transmitted to the transponder and the base station code is extracted by the transponder, a second code is generated by the transponder, which is transmitted to the base station upon an associated request from the base station, whereby before a transmission to the base station the second code is encoded with the extracted base station code, a second encoded transmission information comprising a second identification is generated by the base station with use of the second code and transmitted to the transponder, and at least one memory region of the transponder is released for read and/or write access after the second identification was verified as valid.

Abstract: A method for wireless data communication between a base station and at least one transponder by a high-frequency electromagnetic carrier signal, onto which information packets are modulated, wherein each information packet has a header section, a middle section, and a terminating end section, wherein the middle section has a data field, which contains the data necessary for the data communication, wherein at least one additional control field is inserted into the data field by which the structure of the information packets can be variably adjusted within the region of the data field. The invention relates further to a transponder, a base station, and a data communication system.

Abstract: A method for communicating between a control unit and a plurality of remote units located in the response area of the control unit is provided. The remote units are prompted to transmit a data sequence to the control unit upon receipt of a command sent by the control unit. The control unit transmits a control signal to the remote units substantially simultaneously with the transmission of the data sequence as a function of a communication state, such as the absence of a transmission of the data sequence by at least one remote unit or an at least partially simultaneous transmission of the data sequence by more than one remote unit. In this way, communication methods can be shortened, in particular in terms of time, without adversely affecting communication reliability.

Abstract: In particular embodiments, an error correction during the transmission of the data word is made possible through the change of the modulation state at pre-defined time points.

Abstract: A method and apparatus for wireless data transmission is provided between a base station and a backscatter-based transponder, in which the transponder generates a presence signal after initialization or at predetermined time intervals, independent of data transmitted by the base station. The presence signal is generated by phase modulation and backscattering of a carrier signal transmitted by the base station.

Abstract: A method for access control to at least one memory area of a passive and/or backscatter-based transponder is provided. In the method for access control, depending on an identification selection criterion, a first or at least one second identification within the transponder is activated, the activated identification upon an appropriate request by reader unit is transmitted to said unit, the at least one memory area of the transponder is divided into memory blocks with a settable size, access control information is assigned to a respective memory block, and read and/or write access to a specific memory block is released or blocked depending on the associated access control information and the identification selection criterion.

Abstract: A method for wireless data transmission, for example for RFID systems, between a base station and a transponder is provided. For wireless data transmission between a base station and a transponder, data are wirelessly and bidirectionally transmitted between the base station and the transponder through a first interface of a first interface type using a first data transmission protocol, and data are wirelessly and bidirectionally transmitted between the base station and the transponder through at least one second interface of a second interface type using a second data transmission protocol. The first data transmission protocol and the second data transmission protocol correspond at least in part.