Abstract: A fractional-N frequency synthesizer has a VCO with an output for supplying an output signal of a particular frequency, and an input for receipt of a control signal for controlling the operation of the VCO so that it locks in on a reference frequency. Compensation circuitry is coupled to the input for compensating the output signal for phase jitter. The compensation circuitry has a charge pump that supplies a compensation current to the input. The timing is derived from the output signal, thus rendering the compensation current independent of the frequency range of the VCO and of the reference frequency.

Abstract: The invention relates to a method of controlling the operation of a network in which stations share a communication channel. The upstream link of this channel is divided into time slots (4), consisting of a data slot (6) and m control minislots (51a, . . . , 51i, . . . , 51m). This method, comprising a reservation step provided for the transmission, within the minislots, of data packet transmission requests to a head-end station and a transmission step provided for the transmission of these data packets when corresponding acknowledgement signals have been returned to the concerned stations by the head-end station, also comprises an additional congestion resolution step, provided for improving the performance of transmission by an analysis of the occurrence of collisions between transmission requests within the minislots and a subsequent modification of the timing signals of the channel.

Abstract: In a CATV return channel between a transmitter and a headend receiver, the transmitter is provided with a precoder having programmable but fixed coefficients. The receiver is provided with an ingress rejection filter (IRF) having programmable but fixed coefficients. A non-precoded training sequence is sent from the transmitter to the receiver during a training interval. A multipath and an ingress in the CATV return channel are estimated at the receiver based upon the training sequence sent by the transmitter and received by the receiver. The precoder coefficients and the IRF coefficients are calculated and the precoder and the ingress rejection filter are programmed with the calculated coefficients, respectively. The precoder and the ingress rejection filter use the respective calculated coefficients during a data transmission interval to simultaneously compensate for undesirable effects of multipath and ingress noise in the CATV return channel during data transmission from the transmitter to the headend.

Abstract: The device comprises a recording head including: a chamber plate having oppositely situated first and second faces, pressure chambers being formed as through holes extending between the first and second faces of the chamber plate, the pressure chambers being arranged in substantially parallel first and second rows; a nozzle plate attached to one of the faces of the chamber plate, said nozzle plate comprising a number of nozzle openings corresponding to the number of pressure chambers, each nozzle opening communicating with one of the pressure chambers; a piezoelectric actuator element associated with each pressure chamber, said actuator element having an active direction and comprising at least one layer of piezoelectric material and at least two electrode layers which are arranged such that the dimension of the actuator element in the active direction is varied upon application of an electric voltage between the electrode layers, the actuator element being arranged in cooperative relationship with the associ

Abstract: This invention relates to a reference voltage generator which provides for an optimum control of the output voltage as a function of temperature. The generator comprises two transistors, two current sources, two resistors, and a third transistor supplying current into a charge resistor. It also comprises, connected between the first and second transistors and the current sources, a pair of transistors whose bases are jointly connected to the base of the third transistor.