Abstract: A filter bank configuration for a hearing device has filters in an analysis filter bank and corresponding filters in a synthesis filter bank that are coupled pair-wise to form a channel in each case. In order to compensate for a hearing loss, sub-band signals are amplified in the individual channels with the aid of multipliers. In the process, an audible distortion of an output signal Y of the filter bank configuration as a result of differences between amplification factors of the multipliers of neighboring channels should be prevented. Here, at least one channel changes a phase of a sub-band signal transmitted by the channel such that a difference between a group delay of the filter bank configuration and a prescribable reference value is reduced for at least one predetermined frequency. The filter bank configuration is particularly suited to hearing aids.

Abstract: The circuit complexity or the filter order, respectively, of an analysis/synthesis filter bank system especially for hearing aids is to be reduced. For this reason, the stop-band attenuation of at least one of the transfer functions of the analysis filter bank is composed of a separately configurable, frequency-independent analysis basic attenuation component and a separately configurable frequency-dependent analysis attenuation component. Furthermore, the stop-band attenuation of at least one of the transfer functions of the synthesis filter bank is composed of a separately configurable, frequency-independent synthesis basic attenuation component, a separately configurable, frequency-dependent first synthesis attenuation component and a separately configurable, frequency-dependent second synthesis attenuation component which is also dependent on the manipulation of the sub-band signals.

Abstract: The object of the invention is to make sub-band processing in hearing aids less computationally intensive. For this purpose a filter bank system comprising an analysis filter bank (AFB) for decomposing an input signal into sub-band signals, a processing device for amplifying at least one of the sub-band signals, and a synthesis filter bank (SFB) for combining the processed sub-band signals into an output signal is provided. The sub-band signals are oversampled and downsampled compared to the input signal. The stopband attenuations of the individual filters of the AFB and SFB are at least as high as a predefined signal-to-noise ratio increased by an attenuation value which is a function of the oversampling factor, the downsampling factor and possibly the gain. The magnitude frequency response of the SFB is approximately matched to the magnitude frequency response of the AFB.

Abstract: A filter bank configuration for a hearing device has filters in an analysis filter bank and corresponding filters in a synthesis filter bank that are coupled pair-wise to form a channel in each case. In order to compensate for a hearing loss, sub-band signals are amplified in the individual channels with the aid of multipliers. In the process, an audible distortion of an output signal Y of the filter bank configuration as a result of differences between amplification factors of the multipliers of neighboring channels should be prevented. Here, at least one channel changes a phase of a sub-band signal transmitted by the channel such that a difference between a group delay of the filter bank configuration and a prescribable reference value is reduced for at least one predetermined frequency. The filter bank configuration is particularly suited to hearing aids.

Abstract: The circuit complexity or the filter order, respectively, of an analysis/synthesis filter bank system especially for hearing aids is to be reduced. For this reason, the stop-band attenuation of at least one of the transfer functions of the analysis filter bank is composed of a separately configurable, frequency-independent analysis pass-band attenuation component and a separately configurable frequency-dependent analysis attenuation component. Furthermore, the stop-band attenuation of at least one of the transfer functions of the synthesis filter bank is composed of a separately configurable, frequency-independent synthesis pass-band attenuation component, a separately configurable, frequency-dependent first synthesis attenuation component and a separately configurable, frequency-dependent second synthesis attenuation component which is also dependent on the manipulation of the sub-band signals.

Abstract: The object of the invention is to make sub-band processing in hearing aids less computationally intensive. For this purpose a filter bank system comprising an analysis filter bank for decomposing an input signal into sub-band signals, a processing device for amplifying at least one of the sub-band signals, and a synthesis filter bank for combining the processed sub-band signals into an output signal is provided. The sub-band signals are oversampled and downsampled compared to the input signal. The stopband attenuations of the individual filters of the AFB and SFB are at least as high as a predefined signal-to-noise ratio increased by an attenuation value which is a function of the oversampling factor, the downsampling factor and possibly the gain. The magnitude frequency response of the SFB is approximately matched to the magnitude frequency response of the AFB.

Abstract: A method for preparing an intermediate position delivered analog band pass signals includes the steps of sampling analog/digital conversion, frequency shift, and digital filtering. To advantageously ensure an efficient processing of frequency signals of different transmission norms, certain conditions for the sampling frequency and the utility spectral portion are preferably specified.

Abstract: In order to allow a flexible allocation of transmission capacities in a radio transmission system, without disrupting or interrupting existing radio connections, a control device is provided which, in the event of a change in the transmission channels, adjusts one or more of the transmission parameters in a central station and in affected subscriber stations in such a way that the bandwidth of the available radio channel is optimally utilized. For this purpose, the modems present in the central station and in the subscriber stations are equipped with two transmitted signal paths and two paths and two received signal paths, only one of received signal paths (ENC1, ENC2, IF1, IF2, MOD1, MOD2, DEM1, DEM2, DF1, DF2, DEC1, DEC2), only one of which is activated in each case for a signal transmission. The outputs of the transmitted signal paths and the inputs of the received signal paths are equipped with frequency splitters.

Abstract: The frequency multiplexer device for combining n single signals of bandwidth (B), sampled with a sampling frequency (fa/n), includes a device for performing a Fourier transformation (FFT) of the single signals to obtain complex input signals having imaginary portions and real portions and a number of circuit devices for generating an output signal for multiplexing from the imaginary portion and the real portion of each complex input signal. Each output signal generating device includes respective different chains (111) of serially connected delay elements (110, D) for delaying the real and imaginary portions to form differently delayed imaginary real and signal portions; circuit devices for combining (+) and weighting pairs of the differently delayed real and imaginary signal portions to be weighted with respective weighting factors (.gamma.h(5), -.gamma.h(1), .gamma.h(3)) to form respective weighted combined signals for each different weighting factor.

Abstract: A frequency and phase regulating circuit, particularly for a digital complex-value vestigial sideband signal or Nyquist flank-filtered signal, with a regulating loop having a filter device which generates, from the signal to be regulated, a symmetrical double sideband signal band-delimited to a reference frequency. This regulating circuit is particularly suitable for a digital TV demodulator.

Abstract: For preparation of sampled values represented as two's complements, a two's complement clipping of the least significant bits(LSB) occurs. In place of the removed bits (LSB), the synchronization information (s(k)) is added with an average value depending on the quantization step. No dominant spectral lines for frequencies f greater than zero are permitted to occur in the useful spectrum for this synchronization information. Errors which are caused by removal of the least significant bits and by addition of the synchronization information are largely compensated by these features.

Abstract: The filter circuit arrangement provides the properties of an FIR filter of length N, with K (K.gtoreq.2) cascaded FIR-filter members. One FIR-filter member (5.K) is formed as an equalizer filter of length N.sub.A and the remaining FIR-filter members (5.1 to 5.(K-1)) are 1/M band filters of length N.sub.k, so that ##EQU1## whereinP.sub.k =N.sub.k -2.left brkt-bot.[1/2(N.sub.k -1)]/M.sub.k .right brkt-bot..

Abstract: The switchable dividing network includes two individual filters whose center frequencies are selected from the group consisting of f.sub.a /8, 3f.sub.a /8, 5f.sub.a /8 and 7f.sub.a /8. The passband of its transmission function is shiftable to other frequency ranges by changing signs of a few coupling devices.

Abstract: In a demodulator for a complex-value vestigial sideband signal, a Nyquist slope filter which consists of two subfilters (Ra, Ia) is used, a filter device (FBASTP) being connected downstream of, or also capable of being integrated in, the said Nyquist slope filter, in order to suppress subcarriers, specifically in such a way that the real parts (Ra) and imaginary parts (Ia) of the sub-filters can be combined in each case.

Abstract: A device for digital demodulation of the video and audio elements of a television signal has a digital preprocessing stage for conditioning a complex digital signal for digital demodulation of a television signal at intermediate frequency, a first complex mixing device shifting the video sub-carrier to the frequency 0, a common mixing device used on the input side for the demodulation of the audio signals, and the audio signal processing is not split until after this mixing device. Therefore, fully digital signal processing is possible for television signals from the intermediate frequency, with limited filter complexity.

Abstract: A device for processing a modulated real analog television signal has a digital preprocessing stage for conditioning a complex digital signal for digital demodulation of a television signal at intermediate frequency. The digital signal preprocessing is carried out such that subsequent demodulation of the video and audio elements can be carried out at a favorable cost. Therefore a fully-digital signal processing for television signals, from the intermediate frequency, with a limited filter cost is possible.

Abstract: A device for digital demodulation of the video and audio elements of a television signal has a digital preprocessing stage for conditioning a complex digital signal for digital demodulation of a television signal at intermediate frequency, mixing devices for video and audio elements of the complex digital signal shifting the video sub-carrier and the audio sub-carrier, which is offset by the video sub-carrier frequency, to the frequency 0, digital audio-FM demodulators and parallel paths of mixing devices for the demodulation of the audio signals, so that fully digital signal processing of television signals from the intermediate frequency, with limited filter complexity can be performed.

Abstract: The present invention relates to a multicarrier demodulator for separating and demodulating a digitalized frequency multiplexed signal into a plurality (L) of individual channel signals, with the separation being performed using a frequency division demultiplexer (FDM). The separated channel signals are each filtered using bandwidth limitation filters and thereafter demodulated using a synchronous demodulator. Following demodulation, the signals are filtered by interpolation filters, data (Nyquist) filters, and subsequently decided upon in a decider. The invention is characterized by the fact that the demodulator operates upon a pair of phase displaced complex channel signals.