Abstract: In one embodiment, a method includes receiving an instruction for a transceiver of a device to transmit a first data frame; in response to the instruction, generating a first control signal for a switch to couple the transceiver to a first antenna for transmission of the first data frame by the transceiver via the first antenna; determining whether the transceiver has received within a pre-determined time interval after the transmission of the first data frame a second data frame containing an acknowledgement message confirming successful receipt of the first data frame by another device; and, if the transceiver has not received within the pre-determined time interval after the transmission of the first data frame the second data frame, then generating a second control signal for the switch to couple the transceiver to the second antenna for re-transmission of the first data frame by the transceiver via a second antenna.

Abstract: In one embodiment, a detection unit includes a sequence providing unit to provide a third group of derived sequences. The sequence providing unit has a counting unit and multiplexers connected to the counting unit. Fixed values are applied at the inputs of the multiplexers and the sequence providing unit provides the derived sequences of the third group at the outputs of the multiplexers. The third group for each first pseudo noise (PN) sequence has a derived sequence assigned to the first PN sequence. The detection unit includes a correlation unit, which is connected to the sequence providing unit and formed to calculate correlation results by correlating the differentially demodulated signal with each derived sequence of the third group. The detection unit includes an evaluation unit, which is connected to the correlation unit and is formed to derive the values of the data symbols by evaluating the correlation results.

Abstract: The invention relates to a detection unit for detecting data symbols which are contained in a differentially demodulated signal and to which one respective PN sequence from a supply of sequences can be allocated at the transmission end. The inventive detection unit comprises the following units: a) a sequence supplying unit that is configured for supplying a third group of derived sequences.

Abstract: A device is disclosed for converting a complex-valued bandpass signal into a digital baseband signal having: a) an analog filter unit to filter the complex-valued bandpass signal to produce only the real component from the filtered signal, and to provide a real-valued bandpass signal, b) one analog-to-digital converter that is connected to the analog filter unit and that is designed to convert the real-valued bandpass signal into a digital signal with sampled values with a width of one bit, c) a digital filter unit embodied as a lookup table, to provide a complex-valued filtered signal such that signal components outside of the useful band are suppressed, d) a sampling rate reduction unit to reduce the sampling rate of the complex-valued filtered signal and provide a reduced-rate signal, and e) a mixer unit to convert the reduced-rate signal into the digital baseband signal.

Abstract: Circuit, method for operating a circuit, and use, having a voltage regulator, which has a regulator output for providing a supply voltage, which for the supply can be connected to at least one first digital subcircuit via a first switch and to a second digital subcircuit via a second switch, wherein the voltage regulator is formed to output a first status signal dependent on the supply voltage, and to turn on the first switch by the first status signal is connected to a first control input of the first switch, and the first switch is formed to output a second status signal dependent on its switching state, and to turn on the second switch by the second status signal is connected to a second control input of the second switch.

Abstract: A circuit, control method, and use of a circuit for a sleep mode and an operating mode with a digital CMOS circuit with NMOS field-effect transistors and with PMOS field-effect transistors, with a first load device, whereby source terminals of the NMOS field-effect transistors of the digital CMOS circuit are connected via the first load device to a first supply voltage, and with a second load device, whereby source terminals of the PMOS field-effect transistors of the digital CMOS circuit are connected via the second load device to a second supply voltage, wherein the body terminals of the NMOS field-effect transistors of the digital CMOS circuit are connected directly to the first supply voltage, and the body terminals of the PMOS field-effect transistors of the digital CMOS circuit are connected directly to the second supply voltage.

Abstract: A circuit, an adjusting method, and use of a control loop for adjusting a data retention voltage and/or a leakage current of a CMOS circuit for a sleep mode, wherein the CMOS circuit is operated to control in a measuring mode, whereby in the measuring mode a leakage current exclusively flows through the CMOS circuit, the control loop in the measuring mode adjusts the data retention voltage and/or the leakage current, and the adjustments of the control loop for the sleep mode are stored.

Abstract: Circuit, process, and use of a memory for transmitting and/or receiving in a radio network, with a memory, which has a first interface for reading and writing and a second interface for reading and writing, with an arithmetic logic unit, which is connected to the first interface for reading and writing, with a control unit, which is connected to the second interface for reading and writing, and with a transmit/receive unit, which is connected to the control unit for writing received data via the second interface of the memory and for reading transmit data via the second interface of the memory.

Abstract: A method for determining the occupancy of a transmission channel using a differentially demodulated signal generated at a transmitter-side with the use of PN sequences from a PN sequence set having a first group of first PN sequences and a second group of second PN sequences. The method provides a) at least two subsequences of an initial code sequence, which is assigned to one of the first PN sequences and can be derived from the sequence by logical operations, but is not identical to it, b) the calculation of at least two correlation results by correlating the differentially demodulated signal with each of the at least two subsequences, and c) the evaluation of the correlation results and generation of an output signal to indicate the occupancy of the transmission channel. Also a device for determining the occupancy of a transmission channel.

Abstract: A receiving circuit, method for receiving a signal, and use of a detection circuit and a control circuit of a receiving circuit of a node of a radio network is provided to deactivate an analog signal processing and/or determination of digital data from a signal received over an antenna of the node, when a stored current frame of the digital data has been recognized as valid, and to activate the analog signal processing and/or the determination, when the transmission of the current frame over an interface of the control circuit has been confirmed, whereby the control circuit is connected to the detection circuit and/or an input circuit for deactivation and activation, and whereby the detection circuit is formed to determine the digital data from the received signal.

Abstract: A receiving circuit, use, and method for receiving in a radio network is provided, wherein switching is performed continuously between a first signal, which is received over a first antenna, and a second signal, which is received over a second antenna, to form an input signal. The input signal is converted analog/digitally into a digital signal, the digital signal is correlated to output a correlation signal, the correlation signal is compared with a threshold, and the switching for data reception in a current switch position is stopped when the correlation signal exceeds the threshold.

Abstract: An OFDM receiver is configured for suppressing pilot energy, and DC energy, from received I and Q components prior to estimating amplitude and phase imbalances of the received I and Q components. Hence, amplitude and phase imbalances can be estimated accurately despite channel fading and frequency variations between the transmitter and receiver.

Abstract: An improved data communication receiver technique is provided which avoids demodulation errors due to abrupt phase changes. A receiver is provided for processing an incoming digitized signal. The receiver comprises a pre-processing portion, a phase error correction unit and a signal evaluation unit. The pre-processing portion is adapted to process the digitized signal for providing a non-coherent pre-processed signal. The phase error correction unit is adapted to correct a phase error of the non-coherent pre-processed signal and output a coherent signal. The signal evaluation unit is adapted to extract information from the non-coherent pre-processed signal and to output a data signal representing the extracted information. The phase error correction unit and said signal evaluation unit are configured to operate simultaneously for a predetermined time.

Abstract: A WLAN (Wireless Local Area Network) transmission technique is provided where data is transmitted in two or more different transmission modes at different transmission rates. A transmission gain is determined to be applied when transmitting data. The transmission gain is determined to be transmission mode dependent such that the transmission gain in a first transmission mode is greater than the transmission gain in a second transmission mode if the transmission rate in the first transmission mode is lower than the transmission rate in the second transmission mode.

Abstract: A header detection technique for WLAN (Wireless Local Area Network) receivers is provided. The WLAN receiver comprises a signal processing unit that has analog circuitry and digital circuitry. There is further provided a header detection circuit for detecting a header in a received signal. The header detection circuit is comprised in the analog circuitry. In an embodiment, digital circuitry may be woken up based on a header detect signal that is generated by the header detection circuit. The embodiments may reduce the power consumption of the receiver, and the false detection rate.

Abstract: A device is disclosed for converting a complex-valued bandpass signal into a digital baseband signal.

Abstract: A receiving unit in a communication system for receiving a communication signal. The receiving unit is preferably a wireless local area network (WLAN) receiver. The receiving unit comprises a synchronization data detection section and a frequency error correction section. The synchronization data detection section detects predefined synchronization data included in the received communication signal and computes an initial estimate of a frequency error of the received communication signal. The frequency error correction section corrects the frequency of the received communication signal based on frequency error estimates. An initial frequency error estimate used for a first frequency error correction is received from said synchronization data detection.

Abstract: A phase error correction technique in receivers such as WLAN receivers is provided. Such receivers comprise a phase error correction unit connected to receive an input signal having a phase error and adapted to generate an output signal having a corrected phase error. Further, the receiver comprises a despreader which is adapted to despread a data signal. The despreader is connected to the phase error correction unit to provide the despread data signal to the phase error correction unit. The phase error correction unit is arranged for correcting the phase error dependent on the despread data signal. The despreader may be a Barker matched filter or a CCK matched filter, and there may be provided a multiplexer for selecting one of the filters.

Abstract: A phase error corrector circuit and method are disclosed. In one embodiment, a phase error corrector circuit delays a PSK modulated signal and multiplies the delayed PSK modulated signal by the PSK modulated signal in order to generate a forward phase correction signal. The input signal is then mixed with the forward phase correction signal. In another embodiment, a phase error corrector circuit calculates a forward phase offset of a complex PSK modulated signal. The complex PSK modulated signal is phase shifted in a mixer by a phase difference offset in order to generate a phase corrected signal. A backward phase correction means calculates a backward phase offset based on the phase corrected signal. A subtractor subtracts the forward phase offset from the backward phase offset for outputting a difference phase offset to the mixer.

Abstract: The invention discloses a method for determining the occupancy of a transmission channel with the help of a differentially demodulated signal, which was generated transmitter-side with the use of PN sequences from a PN sequence set, which has a first group of first PN sequences and a second group of second PN sequences, wherein the first and second PN sequences within their respective group differ from one another in a cyclic shift of their chip values and wherein the second group has for each first PN sequence a corresponding second PN sequence, which differs from the first PN sequence in an inversion of every second chip value.