Infineon Technologies Ag

Siemens Aktiengesellschaft

Bin Yang

Xiaofeng Wu

Peter Bohnhoff

Martin Krüger

Ralf Hartmann

Burkhard Becker

Stefan Herzinger

Michael Weber

Steffen Buch

Michael Cujé

Stefan Eibl

Data symbols in the training sequence are rotated at the transmitter end through a phase rotation factor which is specific for a given modulation type that is used. For blind modulation detection at the receiver end, the data symbols are derotated through different phase rotation factors, and a correlation function is formed between the sequences obtained in this way and the original training sequence. The type of modulation which is used is obtained from the phase rotation factor which produces a maximum for the correlation function.

Method and device for transmitting and identifying a modulation type in digital communication systems by way of a phase rotation factor applied to a training sequence

In a method to compensate for a step DC disturbance () in a baseband signal in a homodyne radio receiver, the time profile of the step DC disturbance within a burst is determined. In order to produce a step-corrected baseband signal, the determined time profile () is then calculated from the digitized baseband signal.

Method to compensate for a step DC disturbance in a digital baseband signal in a homodyne radio receiver

A method and a circuit for the digital correction of a frequency of a signal, especially for use in a transmitter/receiver circuit include rotating a signal 'pointer' (i0, q0) using a CORDIC algorithm, through a predetermined angle in a complex I/Q plane corresponding to a correction frequency. The CORDIC algorithm includes micro-rotation blocks corresponding to N stages, and a character table and a register.

Method and circuit for digitally correcting the frequency of a signal

A signal strength compensation unit for mobile radio receivers is connected upstream of the channel estimator and the channel equalizer and compensates for, in particular, the great, brief signal strength fluctuations within a data burst. Likewise, a method for signal strength compensation compensates for brief signal strength fluctuations within the data burst. To these ends, a signal strength average is determined from the signal strengths for the previously received data symbols. The current signal is then aligned with this signal strength average. The inventive signal strength compensation allows the bit error rate during data equalization to be significantly reduced.

Apparatus and method for signal strength compensation of highly time-variant mobile radio channels and reception unit for mobile radio transmission

In a method for error correcting a data signal that is transmitted via a channel and contains data blocks with associated error checking information, the data signal is first equalized, with calculated soft-bit information. In a subsequent step, the error checking information is evaluated with respect to the data block. If the evaluation of the error checking information shows that a single bit error is present in one message bit, the single bit error is corrected only when a condition that is dependent on the soft-bit information is satisfied.

Method and device for error correction of data blocks

A device and a method for automatic frequency correction are used in mobile radio receivers. After channel estimation has been performed, the phases of the received data symbols are analyzed in order to determine the frequency shift. Following the phase analysis, a phase correction of the received data symbols is performed.

Automatic frequency correction for mobile radio receivers

A Viterbi equalizer for equalization of a data signal transmitted via a channel that is subject to interference has at least one add-compare-select unit (ACS), which carries out an ACS operation for each channel state in a time step k. Furthermore, the equalizer has a unit for calculating metric increments in advance and for storing the metric increments. The calculation unit calculates in advance the metric increments relating to all the transitions from a state which can be predetermined in the time step k to the states which can be reached by the transitions in the time step k+1. The metric increments are retained in an output memory such that they can be called up for utilization in the ACS unit.

Device and method for Viterbi equalization with metric increments calculated in advance

A method for channel equalization of received data includes steps of: receiving the received data in a received data packet; calculating filter setting coefficients for an input filter and calculating equalizer setting coefficients for an equalizer; setting the input filter using the filter setting coefficients and setting the equalizer using the equalizer setting coefficients; equalizing the received data using the input filter and using the equalizer; determining channel parameters for the transmission channel from the received data X; storing the channel parameters in a data field; and performing the step of calculating the filter setting coefficients for the input filter and calculating the equalizer setting coefficients for the equalizer by performing a GIVENS rotation of the data field.

Method for channel equalization

A method identifies a pulse sequence having known values and a known length in a signal. According to this method, the mathematical sign of the phase difference between samples of the signal is used to estimate whether the transmitted pulse is a 1 or a 0. Undersampling, carried out to a selectable extent, produces a relatively insensitive response to adjacent channel interference. The sum of the pulses in a window which is proportional to the length of the pulse sequence and to the extent of the undersampling is determined, with the pulse sequence being regarded as being identified at the point in time at which the sum of the pulses in this search window exceeds a threshold value.

Method for detection of pilot tones

A pulse train with known values and a known length contained in a signal is identified. The mathematical sign of the phase difference between successive samples of the signal is used to assess whether the transmitted pulse is a 1 or a 0, and with the sum of the pulses being determined in a window which is proportional to the length of the pulse train. The pulse train is considered as being identified at the time when the sum of the pulses in the search window exceeds a given threshold value.

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Munich, Germany

Bin Yang