Abstract: The invention discloses a method of reading data (dat) from a first transponder (TAG1) into a transceiver (REA). Said (dat) are only transmitted from the first transponder (TAG1) to the transceiver (REA) when a second transponder (TAG2) is present within the RFID communication range of the transceiver (REA) and if a positive authentication procedure between the two transponders (TAG1, TAG2) within the RFID communication range of the transceiver (REA) takes place. The second transponder (TAG2) is preferably a stationary transponder (TAG2), whereas the first transponder (TAG1) may be a mobile transponder. The invention further relates to transponders (TAG1, TAG2) as well as to a transceiver (REA) used in such a method of reading data (dat). Furthermore, the invention relates to a poster (POS), to which a first transponder (TAG1) is attached, and to a poster wall (WAL) for attaching such a poster (POS) and a second transponder (TAG2).

Abstract: The invention relates to a method of determining a plaintext M on the basis of a cipher C and using a secret key d, wherein the secret key d is used in binary form, wherein the plaintext M is determined in each iteration step i for the corresponding bit di and a security variable Mn is determined in parallel therewith, and then a verification variable x is determined by means of a bit-compatible exponent of the secret key d.

Abstract: To enable a method and a system, having at least one base station and/or one data carrier, for transmitting signals between the base station and a number of mobile data carriers operating in the crypto mode or in the plain mode, wherein [a] the base station emits at least one command signal and/or data signal that is provided with at least one identifying pattern, [b] at least one of the data carriers receives the command signal and/or data signal emitted by the base station that is provided with the identifying pattern, [c] at least one of the data carriers that receive the command signal and/or data signal transmits to the base station a response signal that is a response to the command signal and/or data signal, and [d] the base station receives the response signal transmitted by the data carrier.

Abstract: The invention relates to a method of determining a plaintext M on the basis of a cipher C and using a secret key d, wherein the secret key d is used in binary form, wherein the plaintext M is determined in each iteration step i for the corresponding bit di and a security variable Mn is determined in parallel therewith, and then a verification variable x is determined by means of a bit-compatible exponent of the secret key d.

Abstract: The invention discloses a method of reading data (dat) from a first transponder (TAG1) into a transceiver (REA). Said (dat) are only transmitted from the first transponder (TAG1) to the transceiver (REA) when a second transponder (TAG2) is present within the RFID communication range of the transceiver (REA) and if a positive authentication procedure between the two transponders (TAG1, TAG2) within the RFID communication range of the transceiver (REA) takes place. The second transponder (TAG2) is preferably a stationary transponder (TAG2), whereas the first transponder (TAG1) may be a mobile transponder The invention further relates to transponders (TAG1, TAG2) as well as to a transceiver (REA) used in such a method of reading data (dat). Furthermore, the invention relates to a poster (POS), to which a first transponder (TAG1) is attached, and to a poster wall (WAL) for attaching such a poster (POS) and a second transponder (TAG2).

Abstract: To enable a method and a system, having at least one base station (B) and/or one data carrier (D1, D2), for transmitting signals (K, C; A1, A2) between the base station (B) and a number of mobile data carriers (D1, D2) operating in the crypto mode or in the plain mode, wherein [a] the base station (B) emits at least one command signal and/or data signal (K, C) that is provided with at least one identifying pattern (P), [b] at least one of the data carriers (D1, D2) receives the command signal and/or data signal (K, C) emitted by the base station (B) that is provided with the identifying pattern (P), [c] at least one of the data carriers (D1, D2) that receive the command signal and/or data signal (K, C) transmits to the base station (B) a response signal (A1, A2) that is a response to the command signal and/or data signal (K, C), and [d] the base station (B) receives the response signal (A1, A2) transmitted by the data carrier (D1, D2).

Abstract: Radio frequency receivers are implemented in a variety of embodiments. In one such embodiment, a radio frequency receiver is implemented for detecting synchronization patterns in a receiver, particularly in a UHF receiver or a VHF receiver, by which the average current consumption in a system with a receiver, particularly a UHF receiver or a VHF receiver, and with a subsequently arranged controller unit can be reduced. Using a slope detector and by taking the signal state in a shift register, the radio frequency receiver may be implemented by synchronizing a clock recovery unit with an incoming signal. The shift register pattern can be compared against a predetermined pattern, and when the patterns correspond to the pattern of each other or to the completely inverted pattern of the other, the signal is enabled for further processing in a controller unit.

Abstract: In order to provide a method for locating moving objects that will allow high precision in position determination and thus largely eliminate sorting errors, and also to provide a device suitable for executing the method, it is envisaged that on at least one defined location within the reading range of an interrogator (16) arranged in a stationary position, an interference pulse, which influences a response signal transmitted by a transponder (20) carried by a moving object (12) in response to a signal transmitted by the interrogator (16), is exerted on the object (12), and a position of the object (12) is determined in dependence on a time when the influence of the response signal occurred.

Abstract: A circuit arrangement (100) for controlling a first terminal and a second terminal of a preferably contactless integrated circuit, particularly for testing a CMOS circuit, tests a multitude of intergrated circuits simultaneously while using a low-cost structure. The circuit arrangement permits a simple write/read unit assigned to the integrated circuit, and enables the simultaneous testing of a multitude of integrated circuits using a low-cost structure.

Abstract: In order to provide a method for locating moving objects that will allow high precision in position determination and thus largely eliminate sorting errors, and also to provide a device suitable for executing the method, it is envisaged that on at least one defined location within the reading range of an interrogator (16) arranged in a stationary position, an interference pulse, which influences a response signal transmitted by a transponder (20) carried by a moving object (12) in response to a signal transmitted by the interrogator (16), is exerted on the object (12), and a position of the object (12) is determined in dependence on a time when the influence of the response signal occurred.

Abstract: To provide a method and a circuit arrangement (100) for detecting synchronization patterns in a receiver, particularly in a UHF receiver or a VHF receiver, by which the average current consumption in a system with a receiver, particularly a UHF receiver or a VHF receiver, and with a subsequently arranged controller unit (200) can be clearly reduced,

Abstract: A circuit arrangement (100) for controlling a first terminal and a second terminal of a preferably contactless integrated circuit, particularly for testing a CMOS circuit, tests a multitude of integrated circuits simultaneously while using a low-cost structure. The circuit arrangement permits a simple write/read unit assigned to the integrated circuit, and enables the simultaneous testing of a multitude of integrated circuits using a low-cost structure.

Abstract: A method, a circuit arrangement and an apparatus are provided for evaluating an input data signal transmitted by load modulation. A complex data signal is derived from the input data and a mean value signal of the complex data signal is thereafter derived. A complex signal without mean value is also formed from the difference between the complex data signal and the mean value signal of the complex data signal. A first and second quadratic error signals are derived and subsequently a slope signal is derived from the first and second quadratic signals. The method also comprises deriving an information signal by comparing the imaginary part signal without mean value with a decision threshold signal. The information signal indicates whether a value of the input data signal has been generated in a loaded state or an unloaded state during the load modulation.

Abstract: A method of transmitting data signals between a base station and a plurality of moving data media is described, in which, for the purpose of starting a data transmission, the base station emits a command signal in response to which data media, which receive this command signal, each send a response signal to the base station, whereupon the base station selects one of the data media for data transmission, and the transmission of data from the data medium to the base station is triggered solely in this selected data medium.

Abstract: Contactless transmission of information from a passive transponder to a base station takes place in known manner by load modulation in the transponder. The coils of resonant circuits in the base station and in the transponder are coupled to one another, both resonant circuits being tuned as well as possible to the carrier frequency of the base station so that the load modulation of the resonant circuit in the transponder influences the current in the resonant circuit of the base station. Because the two resonant circuits often are not tuned exactly to one another in practice and the transponder is also liable to be moved during the information transmission, it may occur that no signal is recovered by conventional demodulation in the base station.

Abstract: The demodulation of binary amplitude-modulated carrier signals gives rise to special problems, for example in the case of contactless data carriers, because the RF signal is then also used for generating the operating voltage which is limited to a fixed value when the energy is sufficiently high. Moreover, strong interference signals are often superposed on amplitude-modulated signals. For reliable demodulation in such circumstances, therefore, a control signal is subtracted from the input signal and the values of one polarity of the difference are integrated. In order to generate the control signal, the values of one polarity of a further difference between the input signal and a further control signal which is proportional to the former control signal are continuously integrated so as to form an integral signal which is periodically reduced by a fixed fraction. The control signals are derived from said integral signal in a non-linear fashion, preferably by way of the input characteristic of a transistor.

Abstract: A data exchange system is provided including a fixed station and portable data carrier for transmitting energy between the station and carrier. Both the fixed station and the portable data carrier operate in the active mode and the passive mode. The data carrier operates in an active mode only when energy transfer is required.

Abstract: Portable data carriers are known for different applications, for example as so-called smart cards for bank transactions or for access control or for combined applications. For the various applications different subdivisions of the write/read memory in the data carrier are required so that given zones cannot be read and other zones can only be read and not be written. This subdivision is customarily implemented during the manufacture of the card or the chip. In order to obtain a chip which can be flexibly adapted to various applications, in accordance with the invention the memory in the data carrier is subdivided into a number of blocks which are inhibited from reading or writing by read inhibit and write inhibit information stored in different locations in one or two blocks of the memory. The writing in non-inhibited blocks can additionally be made dependent on a previous transmission of a correct password, the password also being stored in one of the blocks in the memory of the data carrier.

Abstract: For compensation of the effects of multi-path reception, a cascade distortion corrector composed of distortion corrector blocks successively connected in series is provided for a digital FM demodulator that needs non-recursive filtering. Each distortion corrector block produces an increase of the phase rotation and of the propagation time as well as a reduction of the reflection factor of the input signal. The cascade distortion corrector leads to a significant reduction of the hardware expense compared to the previously used transversal type filter structures. Sufficient compensation of the multi-path reception effects can be obtained by connecting five or six distortion corrector blocks one after the other.