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Innovationszentrum Fuer Telekommunikationstechnik Gmbh Izt

Innovationszentrum Fur Telekommunikationstechnik Gmbh Izt

Innovationszentrum

Rainer Perthold

Heinz Gerhaeuser

Dieter Weninger

Heinz Gerhauser

Heinz Gerh&auml;user

Gerald Ulbricht

Ernst Eberlein

Albert Heuberger

Christian Neubauer

Maximilian Hofmann

Hartmut Schott

Heinz Gerhafuser

Ingo Rogalsky

Holger Schlegel

Roland Plankenb&uuml;hler

Oliver Rommelfanger

Uwe Gruener

Ralf Gick

Anreas Klose

Roland Zimmermann

Maximilian Hofman

Andreas Klose

Uwe Grüner

A high-frequency signal stimulator system has at least two mutually independent data producers, signal processing and a signal generator. The at least two mutually independent data producers are each configured to produce at least one data packet describing a high-frequency signal to be produced. The signal processing is configured to extract a signal of the data packet produced by the first of the at least two mutually independent data producers and contents of the data packet produced by the second of the at least two mutually independent data producers. The signal generator is configured to produce a high-frequency signal based on the extracted contents.

High-frequency signal stimulator system

A noise generator for generating a noise signal over a frequency spectrum has a first noise source and a first digital filter for a first frequency band, a second noise source and a second digital filter for a second frequency band, and an interpolator and a combiner. The first digital filter has a first sample rate and the second digital filter has a second sample rate, wherein the ratio between the second sample rate and the first sample rate, with regard to a sign, corresponds to a ratio between center frequencies of the second frequency band and the first frequency band, wherein an edge of the second digital filters which determines a lower frequency band limit is steeper than an edge of the first digital filter which determines an upper frequency band limit. The interpolator is configured to adjust an output signal of the first digital filter, with regard to its sample rate, to a sample rate of the second digital filter, wherein the combiner is configured to combine the adjusted output signal from the interpolator and the output signal of the second digital filter.

Noise generator

An apparatus for modifying a sampling rate includes a forward transformer for forming a first version of a spectrogram by means of transformation with a first transformation length from an information signal with a first sampling rate. The apparatus includes a processor for forming a second version of the spectrogram with a lower bandwidth than the first version. The apparatus includes a reverse transformer for forming a coarsely pre-modified information signal with a second sampling rate that is reduced with respect to the first sampling rate, by means of reverse transformation of the second version of the spectrogram with a second transformation length that is reduced with respect to the first transformation length. The apparatus includes a time domain interpolator for acquiring an information signal with a third sampling rate that is modified with respect to the second sampling rate, by means of interpolation of the pre-modified information signal.

Apparatus for modifying a sampling rate system including an apparatus for modifying a sampling rate and method for modifying a sampling rate

A receiver for receiving an analog signal having a frequency band to be digitalized has a filter unit having at least two filters for at least two receive paths, an AD converter per receive path, and digital signal processing. The filters are coupled to a common signal source in order to obtain the analog signal having the frequency band to be digitalized, and configured to divide the frequency band to be digitalized into at least two sub-bands for the at least two receive paths. The analog-to-digital converters are configured to digitalize the signals of the at least two sub-frequency bands. The digital signal processing is coupled to the at least two analog-to-digital converters in order to obtain the at least two digitalized signals and merge the at least two signals to be digitalized. The at least two filters, with regard to their filter characteristics, are configured such that the at least two sub-frequency bands have a relative bandwidth of &#x3c;1:2.

Receiver

The present invention describes an amplifier adjusting device for an amplifier element which is adjustable as a function of amplification factor and is coupled to a frequency domain selecting element for adjusting at least to frequency domains. The amplifier adjusting device includes a memory in which at least two amplification factors may be stored, the at least two amplification factors being assigned to the two at least two frequency domains, an amplification factor adjusting element configured to select, depending on a current frequency domain, a corresponding amplification factor from the memory in order to adjust the adjustable amplifier element, and an amplification factor estimator configured to correct, based on an analysis of a signal amplified by means of the adjustable amplifier element in accordance with the selected amplification factor, the selected amplification factor and store the corrected amplification factor in the memory.

Amplifier adjusting device, system including an amplifier adjusting device and method for operating an amplifier adjusting device

Calibration device for a signal processing device including an input stage, a signal processing stage and an output stage includes an output stage calibrator. The output stage calibrator includes a test signal source adapted to be coupled to the output stage, a feedback channel connectable between output of the output stage and input of the input stage, and a signal analyzer which couples to the input stage. The test signal source provides a test signal to the output stage which is supplied to the input stage via the feedback channel after processing. The signal analyzer analyzes the test signal after processing by the input stage and determines, based on analysis, deviations of actual output amplification of the output stage at a set output amplification of the output stage and/or deviations of actual input amplification of the input stage at a set input amplification of the input stage.

Calibration device, signal processing device, and user interface for the same

A method for determining a time difference between a first and a second time of arrival of the signal is described, the method including: receiving a first representation of the signal at the first time of arrival; receiving a second representation of the signal at the second time of arrival; correlating at least a first time-domain representation of the signal and a second time-domain representation of the signal to obtain a first time difference information; evaluating a phase difference relation between a first frequency-domain representation of the signal and a second frequency-domain representation of the signal to obtain a second time difference information; and determining the time difference between the first and the second time of arrival of the signal based on the first and the second time difference information, or based on a time difference information derived from the first time difference information and the second time difference information.

Method and system for determining a time difference, method and system for finding a position of a transmitter

An apparatus for converting an analog signal into a digital signal includes: two identical analog-to-digital-converters converting the analog signal into first and second digital time domain signals; first and second transformation units transforming the first and second digital time domain signals into first and second digital frequency domain signals; a frequency compensation unit modifying the second frequency signal to reduce a difference between wanted signal components of the second and first frequency values caused by a difference between frequency responses of the analog-to-digital converters; a comparison unit determining for a same frequency bin corresponding first and second energy values associated to corresponding frequency values of the first and second digital frequency domain signal, and determining a minimum energy value thereof; and a selection unit selecting for a same frequency bin of the digital frequency domain signal the digital frequency domain signal associated to the minimum energy value.

Apparatus and method for converting an analog time domain signal into a digital frequency domain signal, and apparatus and method for converting an analog time domain signal into a digital time domain signal

An apparatus for frequency-selective occupancy detection of a channel in a frequency band includes a detector for detecting a receive spectrum in the frequency band, a provider for providing node frequencies, a determiner for determining node level values, a determiner for determining the threshold curve and a comparer. The provider provides the node frequencies for a threshold curve with respect to a noise floor in the frequency band. The determiner determines the node level values at the node frequencies based on receive level values of the receive spectrum. The determiner determines the threshold curve in the frequency band based on the provided node frequencies and the node level values at the node frequencies. The comparer compares a current power of the receive level values in the channel with a reference power in the channel predetermined by the threshold curve to detect occupancy or non-occupancy of the channel depending on the comparison.

Apparatus and method for frequency-selective occupancy detection

A detector for detecting a possible transmission of data according to an embodiment of the present invention includes a receiver adapted to the determine a spectral density in the frequency range of an electromagnetic spectrum and an evaluating circuit coupled to the receiver and adapted to determine an effective channel capacity based on the determined spectral density. The evaluating circuit is further adapted to compare the determined effective channel capacity with a threshold value and adapted to generate an evaluation signal indicating a possible presence of the transmission of data based on a result of the comparison.

Method and detector for detecting a possible transmission of data

An apparatus according to an embodiment of the present invention for providing a reduced representation in a frequency-domain, based on a time-based RF signal, has a time-frequency converter adapted to transform the time-domain RF signal to obtain a frequency-domain representation based on the time-domain signal and an entropy encoder adapted to obtain the reduced representation based on the frequency-domain representation by entropy encoding.

Apparatus and method for providing a reduced representation based on a time-domain RF signal

An apparatus for simulating a signal composed of a plurality of individual signals from respective signal locations at a simulation location, having a provider for providing the plurality of individual signals in the time domain, a transformer for transforming the individual signals to the frequency domain, a processor for processing the individual signals transformed to the frequency domain each depending on a signal channel existing between the simulation location and the respective signal location, a combiner for combining the processed individual signals transformed to the frequency domain to a combined signal, and a transformer for transforming the combined signal to the time domain for generating the simulated combined signal at the simulation location.

Concept for realistic simulation of a frequency spectrum

A device for predistorting a transmission signal to be transmitted over a nonlinear transmission path comprises an estimator for determining an error signal depending on the transmission signal and a previously registered transfer characteristic of the nonlinear transmission path. The error signal represents an estimate of an error generated due to the nonlinearity of the trans-mission path. A time-dispersive element is provided to produce a correction signal by a temporal extension of the error signal. A combiner is provided to combine the transmission signal and the correction signal. As a result of the temporal extension of the error signal, an error signal segment in the frequency spectrum of a transmission signal transmitted by the nonlinear transmission path is shifted away from the useful frequency range of the transmission signal.

Device and method for predistorting a transmission signal to be transmitted via a nonlinear transmission path

A device for pretreating a signal to be transmitted over a transmission path, wherein the transmission path comprises a band-pass filter whose pass-band width is smaller than a predetermined bandwidth and a non-linear amplifier, includes a linearization means for performing a linearization of the signal to be transmitted before the transmission of the same, such that a non-linearity caused by the non-linear amplifier is counteracted. Further, the device includes a signal-shaping means downstream to the linearization means comprising a frequency response such that the overall frequency response of the signal-shaping means and the band-pass filter corresponds to the frequency response of a filter whose pass-band width is at least equal to the predetermined bandwidth.

Device and method for pre-treating a signal to be transmitted using a non-linear amplifier with an upstream band-pass filter

In a method for estimating a non-linear characteristic of an amplifier, an input signal is provided, a reference signal is determined based on the power of the input signal, the input signal is amplified using said amplifier in order to produce an amplified signal, a measurement signal is determined based on the power of the amplified signal and respective samples of the measurement signal are associated with respective samples of the reference signal. A gain value of said amplifier for each sample is determined from the respective samples of the reference signal and the measurement signal. An operating range of the amplifier is divided into a plurality of power sections and an averaged gain value is produced for each power section. Thereafter, a measure of the deviation of the gain values associated with a power section from said averaged gain value is determined. Then, averaged gain values are rejected which have a measure of the deviation which exceeds a predetermined threshold. Finally, an interpolation is performed using averaged gain values which have not been rejected in order to produce an estimation of said non-linear characteristic of said amplifier.

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Weisendorf, Germany

Rainer Perthold