Abstract: Provided are a broadcast switching device, method and terminal for switching between broadcast modes of a terminal, and the broadcast switching device includes: a second signal broadcasting unit; a first signal broadcasting unit; a signal reception module, connected respectively to the first signal broadcasting unit and the second signal broadcasting unit, configured to receive a first signal and a second signal and receive preferentially the first signal; a parsing module configured to parse the first signal to acquire signal strength of the first signal; a determination module configured to compare the signal strength of the first signal with a preset broadcasting strength and obtain a comparison result; and a switching module configured to control the signal reception module to receive the second signal when comparison result is that the signal strength of the first signal cannot meet the preset broadcasting strength.

Abstract: Television reporting records are accessed and processed to generate frequency specific reach values and device frequencies for creatives (e.g., television advertisements). The device frequencies indicating the number of times a creative was presented by use of a particular viewing device. The frequency specific reach values indicating the number of unique viewing devices that were used to present the creative a specified number of times. Estimating frequency specific reach values and device frequencies for a creative for a viewing population. The estimated frequency specific reach values and device frequencies for the viewing population are based on known viewing pattern data for multiple creative airings from a sample of the viewing population (e.g., a subset of the viewing population) and estimated viewing pattern data for the airings for the viewing population.

Abstract: A method, system and server for customizing a broadcast media stream for delivery to a client associated with a user via a communication network. The broadcast media stream comprises a plurality of content segments, such as hosted segments, which are separated by a plurality of musical, informational or generic segments. During streaming the plurality of musical, informational or generic segments are modified based on one or more user preferences such that there content matches more closely the preferred content of the user.

Abstract: A device providing an emergency alert service via a mobile broadcasting, includes a data group formatter to generate a data group containing a part of a signaling data and a RS frame portion, and a broadcasting signal generating unit to generate a mobile broadcasting signal containing the data group. The FIC, included in the data group, is transmitted in a form of a plurality of FIC segments. The FIC segment header includes a wake-up identifier field indicating whether a mobile broadcasting receiver performs a wake-up function to automatically turn on a power and to provide the emergency alert message.

Abstract: A method may include receiving identification information associated with each of one or more users. Interactions may be received from the one or more users relating to content displayed on a television device. Interaction information associated with the interactions may be captured, wherein the interaction information includes at least interaction type information, interaction status information, interaction origin information, and user identification information. The captured interaction information may be stored. A request to display at least some of the captured interaction information may be received. At least some of the captured information may be retrieved and displayed responsive to the request.

Abstract: A clock synchronized control system includes a controller configured to control at least one function of a work machine. The controller may also be configured to select a clock source from among a plurality of external clock sources based on a predetermined order. The controller may be further configured to obtain information from the selected clock source. The controller may also be configured to use the obtained information to affect the at least one function of the work machine.

Abstract: Methods of packet-based synchronization in non-stationary network environments can include accumulating timestamps transmitted in packets between master and slave devices that are separated from each other by a packet network. Operations are also performed to determine whether first timestamps accumulated in a first direction across the packet network demonstrate that a first packet delay variation (PDV) sequence observed from the first timestamps is stationary. Thereafter, estimates of at least one of frequency skew and phase offset between the master and slave clocks are acquired using a first algorithm, from the first timestamps accumulated in the first direction. These operations of determining further include determining whether second timestamps accumulated in a second direction demonstrate that a second packet delay variation (PDV) sequence observed from the second timestamps is stationary.

Abstract: A communication device includes a memory to store data and a processor to receive data, to convert the received data and a same data of the received data among the stored data into a predetermined format, and to transmit data resulting from the data conversion.

Abstract: A node is configured to receive first optical channel data unit (ODU) signals; encapsulate the first ODU signals into a second ODU signal; distribute data of the second ODU signal to a group of third ODU signals; encapsulate each of the third ODU signals into a respective optical channel transport unit (OTU) signal; and transmit each of the OTU signals on a respective optical channel of a group of optical channels. Each optical channel, of the group of optical channels, has a corresponding one of group of wavelengths. The data of the second ODU signal is carried by the group of optical channels.

Abstract: Disclosed is a signal processing device that reduces the influence of an interfering wave to suppress the deterioration of a BER even if narrow-band noise is included in a communication band. In the signal processing device, which is capable of performing an FFT and performing a window function process as preprocessing before the FFT and achieves OFDM demodulation, the window function process is skipped to perform an FFT on a received signal if the frequency of narrow-band noise included in the received signal coincides with the subcarrier frequency of OFDM within a predetermined range. If the frequencies do not coincide with each other, the FFT is performed after the window function process is performed on the received signal.

Abstract: An OLT controller makes each optical transceiver transmit a search signal at a prescribed time so that the search signals reach all ONU connection ends of an optical transmission path. In the case where an ONU connected to the ONU connection end of the optical transmission path is unregistered, when the ONU controller receives the search signal, the ONU controller tunes a wavelength of an optical transmitter of the ONU to a wavelength corresponding to the search signal and makes the optical transmitter transmit a response signal to an OLT.

Abstract: An apparatus comprising at least one processor configured to implement a method comprising receiving a path computation request comprising at least one path computation constraint, and determining whether there is a path through an optical network that satisfies the path computation constraints. Also disclosed is an apparatus configured to process a data structure comprising a flags field comprising at least one flag having one of an active state or an inactive state, wherein each flag is representative of an optical quality constraint.

Abstract: A method of optical communication comprising encoding four modulated symbols to generate four encoded symbols in two orthogonal polarizations and transmitting the four encoded symbols in two successive time slots. An optical communication apparatus comprising a processor configured to receive two sequences of digital symbols in a plurality of time slots, wherein the two sequences correspond to two components of two orthogonal polarizations, wherein one digital symbol per polarization is received in each of the plurality of time slots, divide each of the two sequences into a plurality of groups using a modulo operation of time, wherein each group comprises two digital symbols received in two consecutive time slots, and adaptively equalize the four digital symbols of the two consecutive time slots using a 4×4 matrix to generate four modulated symbols, wherein the 4×4 matrix comprises 16 tap-vectors.

Abstract: A data receiver has a reception circuit and a fail-safe circuit. The reception circuit has an input amplifier, a logic signal processing circuit, and a reception stop control circuit. The fail-safe circuit has a high-pass filter, a comparator, and a pulse width extending circuit. The reception circuit receives a serial data of differential input signals based on a predetermined standard, converts the serial data into a serial data of a single-ended output signal, and outputs a converted serial data. The fail-safe circuit detects whether the differential input signals have a nonstandard small amplitude and outputs a fail-safe detection signal indicating a detection result.

Abstract: Methods and apparatuses of a mobile subscriber transmitting information to a base station are disclosed. One method includes identifying an uplink transmission condition. If the uplink transmission condition is identified, the mobile subscriber transmits a message over multiple uplink frames using multiple uplink frame types. The mobile subscriber may inform the base station that it is transmitting the message over the multiple uplink frames.

Abstract: A method of encoding data for transmission from a source to a destination over a communications channel is provided. A plurality of redundant symbols are generated from an ordered set of input symbols to be transmitted. A plurality of output symbols are generated from a combined set of symbols including the input symbols and the redundant symbols, wherein the number of possible output symbols is much larger than the number of symbols in the combined set of symbols, wherein at least one output symbol is generated from more than one symbol in the combined set of symbols and from less than all of the symbols in the combined set of symbols, and such that the ordered set of input symbols can be regenerated to a desired degree of accuracy from any predetermined number, N, of the output symbols.

Abstract: Wireless uplink communication is disclosed which includes dividing information bits into first and second sets of information bits. The first set of information bits is encoded into a first set of coded bits, while the second set of information bits is encoded into a second set of coded bits. The first and second sets of coded bits are rate matched into a defined number of bits generating first and second sets of rate-matched coded bits. The first and second sets of rate-matched coded bits are interleaved using various interleaving methods to generate an interleaved set of coded bits.

Abstract: This disclosure describes techniques for operating a client device to communicate with a wireless access point to validate data within a frame by comparing channel quality metrics and duration metrics to thresholds. Information received within a validity window may be treated as correctly received even if the frame fails a subsequent verification process or if reception of the frame is terminated prior to the end of the frame.

Abstract: Disclosed are an apparatus and method for transmitting/receiving control information in a wireless communication system that supports carrier aggregation. According to the present invention, a processor of a base station device that transmits control information configures a component carrier type for each of a plurality of downlink component carriers (DL CCs) in accordance with whether or not each of the plurality of DL CCs can support a relay PDCCH (R-PDCCH), which is a downlink control channel dedicated to a relay node. A transmitting antenna transmits information on the type of each of the configured DL Cs to the relay node.

Abstract: A method for transmitting and receiving a control channel, a base station and a terminal relate to a long term evolution advanced system. The method for transmitting a control channel disclosed by the present document includes: a base station side configuring, for a terminal side, detection-limited subframe cluster information of a control channel, so as to notify the terminal side of the manner by which the base station side transmits the control channel. The present document also discloses a method for receiving a control channel, a base station and a terminal.

Abstract: A radio transmission system based on a frequency divisional multiplexing method is described, comprising an improved method for estimating symbol timing offset and frequency timing offset. The receiver estimates the symbol timing offset based of a block of received symbols based on a cyclic prefix and suffix.

Abstract: A PDSCH resource element mapping method is used for joint transmissions. The method solves a problem of colliding resource elements in joint transmissions, due to interference caused when PDSCH resource elements are transmitted in the resource block of one cell and cell-specific reference signals (CRSs) are transmitted in the same location of the resource block of an adjacent cell. The method is particularly beneficial for coordinated multipoint (CoMP) transmissions. The PDSCH resource element mapping method employs one of three schemes for transmitting the collided resource elements, with minimal interference. In the first scheme, one PDSCH symbol is transmitted over three consecutive CRS-collided PDSCH resource elements. In the second scheme, two PDSCH symbols are transmitted over three consecutive CRS-collided PDSCH resource elements. In a third scheme, CRS-collided resource elements are transmitted using a lower modulation order than is specified by the modulation and coding scheme.

Abstract: A mobile station is classified into one of plural classes based on the reception quality from a base station. The allocations of resource blocks are executed at the base station so that a resource block used for the transmission of a data signal component for a mobile station in a class is not commonly used as a resource block for the transmission of a data signal component for another mobile station belonging to the same class but is commonly used as a resource block used for the transmission of a data signal component for a mobile station belonging to another class. A mobile station, based on the allocation of resource blocks, demodulates a data signal component corresponding to the mobile station after cancelling a data signal component corresponding to a low-quality mobile station.

Abstract: A wireless communication device to facilitate determination of frequency band information comprises a processing system and a wireless communication transceiver. The processing system is configured to identify a carrier frequency stored within the wireless communication device and determine a direct current (DC) subcarrier associated with the carrier frequency. The wireless communication transceiver is configured to synchronize with the DC subcarrier to obtain channel information, wherein the channel information comprises a channel size and a DC subcarrier offset. The processing system is configured to process the DC subcarrier with the DC subcarrier offset to determine a starting frequency of a frequency band associated with the carrier frequency.

Abstract: Systems and methodologies are described herein that facilitate control and data multiplexing for uplink (UL) multiple-input-multiple-output (MIMO) communication within a wireless communication system. As described herein, a device conducting uplink MIMO communication in a wireless communication system can multiplex control signaling and data across one or more of a plurality of layers (e.g., corresponding to spatial layers, codewords, etc.) associated with an uplink transmission. Techniques are described herein for selecting layers of a transmission on which to schedule control signaling and selecting offsets to apply to the control signaling scheduled on selected layers. Further, techniques are described herein for leveraging a multi-layer transmission to increase the efficiency of acknowledgement communication. In addition, techniques are described for selecting a modulation and coding scheme (MCS) to apply to control signaling that is combined with data in an uplink multi-layer transmission.

Abstract: The present invention relates to a method and apparatus for controlling data traffic in a time-division duplex (TDD) system that uses multi-component carriers. The method for controlling data traffic in a TDD system that uses multi-component carriers according to one embodiment of the present invention comprises the steps of: a base station transmitting, to a user equipment, a wireless signal including data through one or more component carriers among a component carrier group including a first element carrier which is a primary cell (PCell) and a second element carrier (SCell) which is a secondary cell, wherein the Pcell and the Scell consist of uplink and downlink subframes in a time division duplex system; and the base station receiving, from the user terminal, a wireless signal including response control information for the data through the second component carrier.

Abstract: A method of sizing bundled resource blocks (RBs) having at least one user equipment (UE)-specific demodulation reference signal in an orthogonal frequency division multiplexing (OFDM) system is disclosed. According to one embodiment, the method includes: receiving configuration information related to at least one UE-specific demodulation reference signal; receiving a plurality of resource blocks (RBs) from a network, wherein the plurality of resource blocks comprises the at least one UE-specific demodulation reference signal, at least one cell-specific demodulation reference signal or data, wherein a number of the plurality of RBs is dependent on a size of a system bandwidth, the size of the system bandwidth corresponding to one of four size ranges; and processing at least one of the received plurality of RBs by bundling the plurality of RBs into RB bundles, wherein the size of each RB bundle is based on the one of the four size ranges.

Abstract: A method for transmitting, by a user equipment (UE), a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH) in a wireless communication system, can include generating a plurality of P DMRS sequences associated with a plurality of P layers respectively, wherein a plurality of P cyclic shifts are allocated to the P DMRS sequences respectively, mapping the plurality of P DMRS sequences to resource elements (REs), and transmitting the plurality of P DMRS sequences to a base station, wherein the plurality of P cyclic shifts are determined based on first and second values, which are indicated by a cyclic shift field in downlink control information (DCI), received through a physical downlink control channel (PDCCH).

Abstract: A method for receiving an aperiodic sounding reference signal (SRS) from a user equipment (UE) at a base station in a time division duplex (TDD) communication system. The method according to one embodiment includes transmitting downlink control information (DCI) including a request of the aperiodic SRS to the UE. The downlink control information includes information for receiving downlink data using multiple antennas from the base station by the user equipment. The method according to the embodiment further includes receiving the aperiodic SRS from the UE in response to the request.

Abstract: A method for transmitting a Channel State Information-Reference Signal (CSI-RS) from a base station supporting multiple transmit antennas to a mobile station. The method according to one embodiment includes transmitting, at the base station, information of one or more CSI-RS configurations to the mobile station; and transmitting, at the base station, at least one downlink subframe mapped with the CSI-RSs to the mobile station. The one or more CSI-RS configurations include i) at least one CSI-RS configuration for which the mobile station assumes non-zero transmission power for the CSI-RS, ii) at least one CSI-RS configuration for which the mobile station assumes zero transmission power for the CSI-RS, or iii) at least one CSI-RS configuration for which the mobile station assumes non-zero transmission power for the CSI-RS and at least one CSI-RS configuration for which the mobile station assumes zero transmission power for the CSI-RS.

Abstract: A method in a user equipment device for estimating a channel upon receiving an enhanced control channel (eCCH) from a network node in a telecommunications system includes distributing the eCCH over multiple resource pairs, where each of the multiple resource block pairs includes a number of resources. Each of the resources is associated with a respective antenna port. The user equipment device identifies an antenna port that is associated with multiple ones of the resources. The multiple ones of the resources are present in different resource block pairs of the multiple resource block pairs over which the eCCH is distributed. Identifying the antenna port is based on how the eCCH is mapped to the multiple resource block pairs. The user equipment device estimates the downlink channel for the eCCH based on the identified antenna port in the multiple ones of the resources in the multiple resource block pairs.

Abstract: The present invention relates to a method for transceiving scheduling signals in a multi-carrier wireless communication system, comprising a step of transmitting, via a predetermined downlink component carrier, a PDSCH transmission scheduling signal on one or more downlink component carriers and/or a PUSCH transmission scheduling signal on one or more uplink component carriers; and a step of transceiving the PDSCH and/or the PUSCH in accordance with the scheduling signals. The scheduling signals can be defined to the same size in a PDCCH transmission region of said predetermined downlink component carrier in the event different MIMO transmission modes are applied to the PDSCH transmission or the PUSCH transmission, or in the event said one or more downlink component carriers or said one or more uplink component carriers have different bandwidths.

Abstract: Provided is a method and apparatus for transmitting a reference signal by a base station in a multi-cell cooperative communication environment. The method for transmitting the reference signal according to the present invention comprises the steps of: transmitting cell ID information of a second cell to a terminal which uses a first cell as a serving cell; generating reference signal sequences in the first cell and the second cell on the basis of the same cell ID; and performing resource element mapping on each of the generated reference signals, generating signals, and transmitting the signals to the terminal, wherein the same cell ID used in generating the reference signal sequences is a cell ID of the first cell or a cell ID of the second cell.

Abstract: Provided are a communication apparatus and a method for receiving a response signal transmitted from a terminal configured with one or more downlink component carriers. The communication apparatus includes a transmitting section and a receiving section. The transmitting section is configured to transmit, to the terminal, downlink assignment information indicating one or more resources for downlink data, each of the one or more resources being assigned to one of the one or more downlink component carrier(s), and configured to transmit the downlink data to the terminal. The receiving section is configured to receive one or more response signals for the downlink data, which are transmitted from the terminal. The terminal makes the phase points of the response signals different in accordance with a number of downlink data which has been successively received.

Abstract: A method and device for sending an aggregated CQI are provided by the disclosure. The method includes a terminal side receiving CSI-RS configuration information and/or interference measurement information sent from a base station side, the terminal side determining a sending sequence of aggregated CQI of each aggregated CSI-RS configuration resource and/or interference measurement resource according to a receiving sequence of the CSI-RS configuration information and/or interference measurement information, wherein each aggregated CSI-RS configuration resource and/or interference measurement resource is aggregated of at least one configuration CSI-RS configuration resource and/or interference measurement resource corresponding to the CSI-RS configuration information and/or interference measurement information, the terminal side sending the aggregated CQI to the base station according to the sending sequence.

Abstract: A full-duplex transceiver is provided with componentry and methods for cancellation of nonlinear self-interference signals. The transceiver is capable of receiving an incoming radio-frequency signal that includes both a desired radio-frequency signal component and a self-interference component caused by the transceiver's own radio-frequency transmission. The transceiver demodulates the incoming radio-frequency signal to generate a first demodulated signal. The transceiver combines an analog corrective signal with the first demodulated signal to generate a second demodulated signal with reduced self-interference. The transceiver processes the first and second demodulated signals to determine a desired incoming baseband signal and to determine nonlinear components of the self-interference signal, such as nonlinearities introduced by the transceiver's power amplifier.

Abstract: A wireless transceiver includes a transmit path configured to generate a radio frequency (RF) transmit signal for transmission via an antenna. A receive path is configured to receive an RF receive signal via the antenna. A circulator-based quadrature duplexer includes an in-phase circulator and a quadrature-phase circulator configured to couple the transmit signal from the transmit path to the antenna while generating a residual transmit signal on the receive path, and to couple the receive signal from the antenna to the receive path. The circulator-based quadrature duplexer promotes cancellation of the residual transmit signal on the receive path.

Abstract: A communication device operating in time division duplex (TDD) mode using multiple antennas is provided herein. The communication device uses receive channel estimation measurements to perform transmit beamforming and multiple input multiple output (MIMO) transmission, based on self-calibration of the various up/down paths via a method of transmission and reception between its own antennas, thus achieving reciprocity mapping between up and down links. Either user equipment (UE) or a base station may routinely perform this self-calibration to obtain the most current correction factor for the channel reciprocity to reflect the most current operating conditions present during TDD MIMO operation.

Abstract: A cognitive MANET system is disclosed that uses TDD (Time Division Duplexing) and TDMA MAC to maintain routes that allow delivery of adequate bandwidth for applications resulting in an efficient way of maintaining information on neighboring wireless terminals and access points by using a routing protocol that has a built in slot reservation algorithm.

Abstract: A method and apparatus for transceiver clock architecture with transmit PLL and receive slave delay lines. In one embodiment, the method includes the generation of a transmitter (Tx) clock signal by adjusting a control voltage of a voltage controlled oscillator to lock a phase and frequency of Tx clock signal to a reference clock signal. In one embodiment, a frequency of the Tx clock signal is a multiple of a frequency of the reference clock signal. In one embodiment, a slave delay line may be used, including a plurality of variable delay buffers that are configured according to the control voltage to generate a receiver (Rx) clock signal in response to a received clock signal that is synchronized with the reference clock signal. The Rx clock signal may be provided to data recovery logic to sample data. Other embodiments are described and claimed.

Abstract: One embodiment relates to a method of calibrating duty cycle distortion. A data rate of a physical layer interface is changed from a lower rate to a higher rate, and a data rate of one or more transceivers associated with the physical layer interface is changed from the lower rate to the higher rate. An electrical idle state is maintained after changing the data rate of the transceiver. Duty cycle distortion calibration for one or more transceivers associated with the physical layer interface is then performed during the electrical idle state. Other embodiments and features are also disclosed.

Abstract: One embodiment includes a circuit system. The system includes a power detector configured to convert an AC signal to a DC signal corresponding to a power amplitude associated with the AC signal. The AC signal can include a periodic signal power null. The system also includes a null-gating circuit comprising a logic switch that is activated to enable sampling of an amplitude of the DC signal and that is deactivated during the periodic signal power null. The system also includes an analog-to-digital converter (ADC) configured to convert the sampled DC signal to a digital signal. The system further includes a processor configured to process the digital signal.

Abstract: In general, techniques are described that insert one or more bits into a digital bit stream to maintain an overall transition density in the digital bit stream. Maintaining the overall transition density facilitates the generation of a recovered clock by a phase-locked loop (PLL) circuit of a receiver. For example, when a data transition ratio for a portion of the digital bit stream is less than a desired data transition ratio, the techniques insert additional bits to increase the overall transition density of the digital bit stream.

Abstract: A clock data recovery circuit including a recovery unit and a loop control unit is provided. The recovery unit generates a recovery clock signal according to an original data signal. The recovery unit locks a frequency of the recovery clock signal to a correction frequency through a first loop, and locks the frequency of the recovery clock signal to a sampling frequency through a second loop. The correction frequency is smaller than the sampling frequency. The recovery unit adjusts the frequency of the recovery clock signal according to a reference clock signal and a first dividing signal in the first loop. The loop control unit switches the recovery unit to the first loop or the second loop according to a frequency difference between the reference clock signal and a second dividing signal.

Abstract: A clock data recovery circuit module including a clock recovery circuit, a frequency comparison circuit and a signal detecting circuit is provided. The clock recovery circuit is configured to output a data recovery stream and a data recovery clock based on an input signal and a clock signal. The frequency comparison circuit is coupled to the clock recovery circuit. The frequency comparison circuit is configured to compare a frequency difference between the data recovery clock and the clock signal to adjust the frequency of the clock signal based on a comparison result. The signal detecting circuit is coupled to the frequency comparison circuit. The signal detecting circuit is configured to receive and detect the input signal, and the signal detecting circuit determines whether to enable the frequency comparison circuit according to the detection result. Furthermore, a method for generating a data recovery clock is also provided.

Abstract: A tokenization system tokenizes sensitive data to prevent unauthorized entities from accessing the sensitive data. The tokenization system accesses sensitive data, and retrieves an initialization vector (IV) from an IV table using a first portion of the sensitive data. A second portion of the sensitive data is modified using the accessed initialization vector. A token table is selected from a set of token tables using a third portion of the sensitive data. The modified second portion of data is used to query the selected token table, and a token associated with the value of the modified second portion of data is accessed. The second portion of the sensitive data is replaced with the accessed token to form tokenized data.

Abstract: A system and method are disclosed for securely transmitting and receiving a signal. A nonlinear keying modulator is used in the transmitter to encrypt the signal using a nonlinear keying modulation technique. A nonlinear keying demodulator is used in the receiver to decrypt the signal.

Abstract: An encryption device that, when voice or image data or the like being encoded is encrypted using a one-time pad (OTP) cipher and then transmitted, reduces a period of time in which a cipher key for the OTP cipher runs out. A first terminal device determines whether to encode transmission data by a first encoding scheme or a second encoding scheme having a lower bit rate than the first encoding scheme, depending on the number of remaining bits of an OTP cipher key, and encodes the transmission data according to the determined encoding scheme, thereby generating encoded data. The first terminal device encrypts the generated encoded data with the OTP cipher using the OTP cipher key, thereby generating encrypted communication data, and transmits the generated encrypted communication data to a second terminal device.

Abstract: Methods and systems for disrupting password attacks using compression are described. A user password may be stored on a mobile computing device. The password may be compressed, for example, using a Huffman compression algorithm, and may be subsequently encrypted using a short secret as a key. The user password may be stored as the compressed and encrypted key. The compressed and encrypted password may be stored such that a brute force password attack, for example, using every possible short secret, would reveal too may possible matches to allow an attacker to select the real password.

Abstract: The embodiments relate to methods and apparatuses for producing secure transmission of a message. The methods are based on production of a basic key that is used for producing respective transmitter keys for a plurality of transmitters. For the ascertainment of the receiver keys by respective receivers, the basic key is transmitted to the receivers, which for their part are able to ascertain a receiver key for checking the integrity of the message from a respective transmitter on the basis of the basic key and an identifier for the transmitter. The receiver ascertains a cryptographic checksum, which, in the course of the integrity check, is compared with a cryptographic checksum that has been produced by the transmitter and sent along by the respective message. The embodiments may be used within the context of automation and sensor networks.