Abstract: A method for blindly detecting a transport format of a convolutional encoded signal is provided. The transport format is unknown and belongs to a set of MF predetermined reference transport formats. The method includes decoding the convolutional encoded signal using a Maximum-a-Posteriori algorithm. The decoding includes considering the MF possible reference transport formats and delivering MF corresponding groups of soft output information, calculating from each group of soft output information a calculated cyclic redundancy check (CRC) word, and comparing the calculated CRC word with the transmitted CRC word. Groups are selected which the calculated CRC word is equal to the transmitted CRC word, and an actual transport format of the convolutional encoded signal is selected from at least one soft output information among last ones of each selected group.

Abstract: The speech is sampled in such a way as to obtain successive voice frames each including a predetermined number of samples, and with each voice frame are determined parameters of a code-excited linear prediction model. The parameters include a long-term excitation digital word vi extracted from an adaptive coded directory LTD, and an associated long-term gain Ga, as well as a short-term excitation word cj extracted from a fixed coded directory STD and an associated short-term gain Gc. The product of the long-term excitation extracted word times the associated long-term gain is summed SM with the product of the short-term excitation extracted word times the associated short-term gain. The summed digital word is filtered in a low-pass filter FLCT having a cutoff frequency greater than a quarter of the sampling frequency and less than a half of the latter, and the adaptive coded directory is updated with the filtered word.

Abstract: The electrical consumption of a cellular mobile telephone is reduced by using fractional-division phase-locked loops receiving a frequency reference from a fairly inaccurate quartz oscillator. Electrical consumption is also reduced by switching the output of the oscillator onto the input of the processing stage when the transmission/reception stage is inactive. The fractional-division phase-locked loops can then be deactivated.

Abstract: A multi-carrier transmission system has a plurality of transceivers, each having a receiver and a transmitter. Data is transmitted between the transceivers by modulating the data onto a multiplicity of carrier waves in the form of multi-bit symbols, wherein each carrier wave constitutes a channel, and wherein the number of bits per symbol (the bit loading), varies between channels and, within a channel, with time, so that each channel has associated therewith a bit loading parameter.

Abstract: Optoelectronic component for converting electromagnetic radiation into an intensity-dependent photocurrent comprising a substrate formed in CMOS technology, in particular, with an integrated semiconductor structure (ASIC) and an optically active thin-film structure arranged upstream in the direction of light incidence and comprising in each case at least one layer made of doped and at least one layer made of undoped semiconductor material, which is connected to a microelectronic circuit arranged on the substrate by means of an insulating layer, within which are situated connecting means for contact-connecting the optically active thin-film structure to the semiconductor structure. The invention is based on the object of providing an optoelectronic component, and a method for fabricating it, which, on the one hand, can be fabricated more simply and, on the other hand, has a reduced dark current.

Abstract: A clock offset compensation arrangement may include a fractional interpolator for applying a trigonometric interpolation to a sampled input signal according to a clock offset signal. It uses transform-based processing in the frequency domain. Compared to a polynomial type interpolation it may be easier to implement, and may achieve a closer approximation to an ideal interpolation. It may reduce the effects of non-linear type errors introduced by truncation of higher powers. The arrangement may be applied to receivers or transmitters of multi-carrier modems, as well as other applications which use rate adaptation or synchronization.

Abstract: An incident signal contains a preamble including a training sequence having a series of pulses whose polarity and time shifts are defined by respective polarity code and time-hopping code. A method includes a digital cross-correlation of the received signal with the training sequence. The cross-correlation algebraically sums in accordance with the polarity code windows of the received signal. The starting points of the windows are determined by the time-hopping code. The cross-correlation further includes detecting the end point of the preamble from the result of the digital cross-correlation. When the size of the receiving buffer, i.e., the size of the window is smaller than the number N of samples of each replica of the training sequence, it is particularly advantageous that the digital cross-correlation be performed iteratively in a block-by-block fashion. The computation of each block is split into M slices which are computed by algebraically summing windows N/M samples long.

Abstract: A method for processing an incident pulsed signal of an ultra wide band type received over a channel by a data device operating in a wireless data communications system is provided. The incident pulsed signal carries information within a super-frame structure. Upon reception of each super-frame structure by a data device, coarse synchronization is performed with another data device acting as a coordinator device for the wireless data communications system. The coarse synchronization uses a first training sequence. Upon reception of each frame allocated to the data device operating within the super-frame structure, channel estimation is performed using a second training sequence. The channel estimation also performs a frame synchronization.

Abstract: A DC/DC converter or power supply is provided that includes a switched-mode regulator, a feedback comparator coupled to the regulator, and an offset voltage circuit coupled to the feedback comparator. A feedback voltage is coupled to the feedback comparator, and the offset voltage circuit adds an offset voltage to the feedback voltage during at least one phase of the switched-mode regulator or at least a portion thereof. Also provided is a method for stabilizing of the output signal of a switched-mode regulator of the type that receives a feedback signal from a feedback comparator.

Abstract: Successive groups of N bits are delivered at a delivery frequency Fe greater than a predetermined frequency PRF. At least one of the successive groups includes at least one subgroup of at least one bit defining at least one digital cue of position and of shape of at least one base pulse within a window of length 1/PRF. This digital cue is converted into the base pulse, and the base pulse is filtered using a high-pass filter for providing a pulse of the ultra wideband type within the window with a temporal accuracy equal to 1/N*Fe.

Abstract: A power amplification device includes an input for receiving a signal having a useful or desired frequency band, and power amplification circuitry of the delta-sigma type connected to the input. The power amplification circuitry exhibits an order greater than or equal to one in the useful frequency band, and an order greater than or equal to one outside the useful frequency band.

Abstract: A power amplification device includes an input for receiving a signal having a desired frequency band. The signal also has a transfer function associated therewith. The power amplification device further includes power amplification circuitry having an order greater than or equal to one, and signal amplifiers connected between the input and the power amplification circuitry. Each signal amplifier has a predetermined gain so that zeros of the transfer function are outside the desired frequency band.

Abstract: A method is provided for decoding a turbo-code encoded signal in a receiver. According to the method, the signal is received from a transmission channel, and the signal is digitally turbo-code decoded. Additionally, a quality information representative of conditions of the channel state estimation is dynamically determined, and the quality information is dynamically compared with a predetermined criteria for defining good or bad estimation conditions. A Maximum-A-Posteriori algorithm in the logarithmic domain is dynamically selected for good estimation conditions, or an approximation of the Maximum-A-Posteriori algorithm in the logarithmic domain is dynamically selected for bad estimation conditions. Also provided is a receiver that implements such a decoding method.

Abstract: With OFDM systems the frequency domain data is the Fourier transform of the received time domain OFDM frames. The time domain frames must be sampled, at the receiver, in synchronism with the transmitter, so that each received frame contains data from only a single transmitted frame. It is vital for this synchronism to be maintained in order to maintain the orthogonality of the frames. A typical multi-carrier system, of the OFDM type, which uses a cyclic prefix permits orthogonality to be maintained when there is a small deviation from exact frame synchronisation. Because the signalling interval includes both an entire frame and the cyclic prefix, which is a repetition of part of the frame, a frame sampled within the signalling interval will contain data from only one frame. Since the signalling interval is greater than the frame period, this gives some leeway in frame alignment. In a multi-carrier system of the OFDM type, an adaptive channel equalizer, operating in the frequency domain, is often used.

Abstract: A RFI canceller, for use in a subscriber line system using multi-carrier modulation, measures a RFI disturbance in carriers falling within a band of frequencies causing the RFI. The RFI ingress into carriers outside the band of frequencies is estimated, and an error correcting signal derived from the estimation of the RFI ingress is subtracted from a received signal. The subscriber line system may be a VDSL system and the multi-carrier modulation may be DMT. The RFI canceller includes a demodulator for demodulating an incoming data stream to provide a first parallel data stream. A parallel to serial convertor converts the first parallel data stream to a first serial data stream. A digital to analogue convertor converts the first serial data stream to a first analogue signal. An analogue RFI canceller circuit combines the analogue signal with an analogue error correcting signal, to produce a second analogue signal.

Abstract: A flash EEPROM memory module acting like a synchronous RAM or ROM, for use in an integrated circuit controlled by a CPU. The module includes an asynchronous flash EEPROM memory with a controllable function and operational mode an interface for communication with a CPU, a state machine arranged to control the function, and a plurality of registers arranged to control the operational mode, the state machine and registers being arranged to be directly controlled by standard CPU signals through the interface.

Abstract: An arrangement for synchronization of nodes in VDSL-systems, or more exactly, synchronization of optical VDSL-nodes which share a common part of a cable in the access network between subscribers and a local station. A time synchronization is provided towards an external system, for instance GPS, which gives a time reference by which the different nodes can be synchronized. The synchronization reduces the near end cross-talk between the VDSL-systems in the different nodes. Preferably, each respective node includes a receiver for a synchronization signal and an internal oscillator with high stability to deliver a stable clock signal.

Abstract: A method for encoding wideband speech includes sampling the speech to obtain successive voice frames each comprising a predetermined number of samples, and determining for each voice frame parameters of a linear prediction model. The parameters include a long-term excitation word extracted from an adaptive coded directory, and a short-term excitation word extracted from a fixed coded directory. The extraction of the long-term excitation word is performed using a first weighting filter. The extraction of the short-term excitation word is performed using a second weighting filter cascaded with a third weighting filter. The first and third weighting filters are equal.

Abstract: A method for encoding speech includes sampling speech to obtain successive voice frames each having a predetermined number of samples, and determining parameters of a linear prediction model for each voice frame. The parameters include a long-term excitation word extracted from an adaptive coded directory using a first linear prediction filter and an associated long-term gain. The parameters further include a short-term excitation word extracted from a fixed coded directory and an associated short-term gain. The adaptive coded directory is updated based upon the extracted long-term excitation word and the extracted short-term excitation word. The first linear prediction filter is updated using the short-term excitation word filtered by a second filter. The second filter has an order greater than or equal to 1 and coefficients thereof depend on the long-term gain for reducing a short-term excitation contribution when a long-term excitation gain is greater than a threshold.

Abstract: A method for controlling frequency of a local oscillator in a DS-CDMA type receiver includes transforming a known spread spectrum signal into a sampled digital signal formed of symbols with a despreaded frequency spectrum, and determining a residual frequency error fe for each symbol including a first residual frequency error fe1. The method further includes correcting the frequency of the local oscillator with the residual frequency errors, and determining an average of absolute values of a predetermined number of successive residual frequency errors. The average is compared with a threshold, and if the average is greater than or equal to the threshold, the local oscillator frequency is corrected using an error equal to −sgn(fe1) (1/T−|fe1|), where sgn is the sign function, | | is the absolute value function and T is duration of a symbol before determining the next residual frequency error associated with the next symbol.