Abstract: At least two inputs, at least one output and a clock source for the inputs are provided in a multiplexer. Each input balances an input signal and is coupled to a transistor circuit having two transistors with collectors commonly connected to a power potential. The transistor circuit can be supplied with a first balanced input signal on a first input signal path connected to the base of the first transistor, and with a second balanced input signal on a second input signal path connected to the base of the second transistor. The two balanced input signals are able to have a predetermined switching potential applied to them under the clocking of a driver circuit. In addition, two outgoing signal paths from the emitter of each transistor circuit can be combined to form at least two output signal paths for the at least one output. In this arrangement, the two output signal paths can be connected symmetrically with respect to a reference-ground potential.

Abstract: A crossbar switch comprises a number of crossing points at which controllable switch elements are arranged, via which an input signal supplied to a row can be interconnected to a column intersecting this row at this crossing point when an interconnection signal is supplied to the respective setting parameter via a control input. The controllable switch elements comprise amplifier elements whose amplifier inputs are connected with the rows and whose amplifier outputs are connected with the columns. The amplifier elements are wired such that they only consume electrical energy when the interconnection signal is supplied to the respective crossing point.

Abstract: In a method and apparatus for transmission of signals, an input signal is supplied to at least one dynamic compressor and the dynamics of the signal is compressed by the dynamic compressor with a degree of compression. The compressed signal is subsequently adapted, in particular limited, in terms of its frequency bandwidth dependent on the degree of compression, such as directly dependent on the degree of compression or dependent on a reference value directly associated with the degree of compression, such as the input level of the signal before the dynamic compressor.

Abstract: A reception unit for a magnetic resonance tomography apparatus has an RF preamplifier connected at its signal input to a local coil with a PIN diode connected in parallel with the signal input and a supply voltage connection of the RF preamplifier being connected to a direct voltage source. The reception unit has a supply node that is connected with the supply voltage connection, the PIN diode and a cross-over switch for alternating connection of the supply node to the direct voltage source or a direct current source.

Abstract: Two amplifier transistors are arranged in parallel and a current source is connected to a common emitter line of the amplifier transistors and produces a temperature-independent quiescent current. In order for both the small-signal gain and the large-signal response to be independent of temperature, the emitters of the two amplifier transistors are connected to one another by a compensation resistor which has a negative temperature coefficient.

Abstract: An antenna amplifier, in particular for a magnetic resonance antenna, has a sheath wave barrier integrated into the signal path of the antenna amplifier in the form of a component designed exclusively for transfer of a differential signal.

Abstract: In a method for local reduction of the operating noise produced by a medical diagnostic or therapy device, antisound is produced locally by a sound source. The sound source used is a highly directional parametric loudspeaker. As a result, disturbing operating noises can be limited locally and suppressed effectively.

Abstract: A controllable two-phase network for production of two output signals at two loads with identical load impedances from an input signal from a source containing a phase path for production of a first output signal, and an amplitude path for production of a second output signal, from the input signal. The phase path contains a trimming resistance and a trimming capacitance in order to influence the phase shift between the input signal and the first output signal. The amplitude path contains a compensation circuit for matching the amplitude of the second output signal to the amplitude of the first output signal. In particular, the two-phase network is designed such that the two output signals have the same amplitude, and the phase of the first output signal has a constant phase shift with respect to that of the second output signal.

Abstract: In a magnetic resonance system and an operating method therefor, a B1 field distribution of a radio-frequency antenna is measured in at least one part of a examination volume of the magnetic resonance system, and then the RF pulses emitted by the radio-frequency antenna are optimized, based on the determined B1 field distribution, for homogenization in a specific volume. An effective volume within the examination volume is determined beforehand for each applied RF pulse and, based on the determined B1 field distribution, the appertaining RF pulse is individually adjusted such that the B1 field is homogenized within the effective volume of the RF pulse.

Abstract: A radio frequency transmitter arrangement for a magnetic resonance apparatus has a distribution unit and an antenna unit, wherein the antenna unit, to generate radio frequency fields, is fashioned in at least two orthogonal modes, and the distribution unit is fashioned for the division of an RF transmission signal into at least two mode feed signals. At least one adjustment unit is provided to adjust the amplitude and/or phase of one of the mode feed signals and is connected with the antenna unit such that each of the mode feed signals generates a radio frequency field in one of the modes. A multiple transmitter arrangement has at least two radio frequency transmitter arrangements and at least two 180° hybrids. A method is provided to determine at least one setting parameter of the adjustment unit.

Abstract: Circuit arrangement for the switchable amplification of variable electrical signals having at least one signal input and a signal output. A switchable amplifier is present between signal input and signal output and is provided with an input, with an output and with a negative feedback path having at least one resistor between input and output. The circuit arrangement further comprises a voltage source, the polarity of which can be reversed by a switching element. In this case, the negative feedback path has a switchable bypass connected in parallel with the at least one resistor. The signals fed in at the amplifier input are furthermore to be fed to the amplifier output in amplified fashion via a first signal path or in unamplified fashion via a second signal path depending on the polarity of the voltage source.

Abstract: At least two inputs, at least one output and a clock source for the inputs are provided in a multiplexer. Each input balances an input signal and is coupled to a transistor circuit having two transistors with collectors commonly connected to a power potential. The transistor circuit can be supplied with a first balanced input signal on a first input signal path connected to the base of the first transistor, and with a second balanced input signal on a second input signal path connected to the base of the second transistor. The two balanced input signals are able to have a predetermined switching potential applied to them under the clocking of a driver circuit. In addition, two outgoing signal paths from the emitter of each transistor circuit can be combined to form at least two output signal paths for the at least one output. In this arrangement, the two output signal paths can be connected symmetrically with respect to a reference-ground potential.

Abstract: A device for amplifying an input signal comprising a semiconductor unit having at least one semiconductor component, and circuit for setting an operating point of the semiconductor unit. The circuit is designed such that during amplification of the input signal, an operating point of the semiconductor unit can be varied automatically and independently for a measured value, in accordance with a predetermined profile of a maximum possible signal amplitude of the input signal between a distortion-optimized setting, for high maximum possible signal amplitude and a noise-optimized setting for a low maximum possible signal amplitude.

Abstract: A crossbar switch comprises a number of crossing points at which controllable switch elements are arranged, via which an input signal supplied to a row can be interconnected to a column intersecting this row at this crossing point when an interconnection signal is supplied to the respective setting parameter via a control input. The controllable switch elements comprise amplifier elements whose amplifier inputs are connected with the rows and whose amplifier outputs are connected with the columns. The amplifier elements are wired such that they only consume electrical energy when the interconnection signal is supplied to the respective crossing point.

Abstract: An amplifier arrangement comprises an active amplification element arranged between a first and a second contact within a first signal path. A signal fed in at the first contact is amplified in the amplification element. Furthermore, a controller for a variably operation of the amplification element, as well as a passive second signal path. The second signal path, which is arranged parallel with the first signal path and bypasses the first signal path, is also contained therein. An ultrasound device contains such an amplifier arrangement.

Abstract: The amplifier device contains a first amplifier element having a first input and a first output. The first output is fed back via a negative feedback path to the input. The negative feedback path contains a controlled current source which brings about a reduction in the noise and also a real finite input impedance.

Abstract: Two amplifier transistors are arranged in parallel and a current source is connected to a common emitter line of the amplifier transistors and produces a temperature-independent quiescent current. In order for both the small-signal gain and the large-signal response to be independent of temperature, the emitters of the two amplifier transistors are connected to one another by a compensation resistor which has a negative temperature coefficient.

Abstract: A controllable two-phase network for production of two output signals at two loads with identical load impedances from an input signal from a source containing a phase path for production of a first output signal, and an amplitude path for production of a second output signal, from the input signal. The phase path contains a trimming resistance and a trimming capacitance in order to influence the phase shift between the input signal and the first output signal. The amplitude path contains a compensation circuit for matching the amplitude of the second output signal to the amplitude of the first output signal. In particular, the two-phase network is designed such that the two output signals have the same amplitude, and the phase of the first output signal has a constant phase shift with respect to that of the second output signal.

Abstract: In a dynamics compressor, an analog signal to be compressed is supplied to a first amplifier stage as an input signal, and the output signal thereof is supplied to the next amplifier stage as an input signal, and so on for a number of successive amplifier stages. Each amplifier stage amplifies its input signal with a stage amplification until it reaches a stage limit level. The analog signal and the respective output signals of the amplifier stages are summed in a summation stage to form a sum signal. Above a minimal level, the magnitude of the curve of the sum signalroughly corresponds to an exponent characteristic of the magnitude of the analog signal.

Abstract: The invention relates to a method and a device for taking an image 2 of an object surface 1 by means of a focusable radiation 3. An array of object elements 4 that covers the object surface is defined; then, for each object element 1, a first signal of the radiation that is focused onto an associated transmitter line 5, including said object element, in the object surface is emitted, and a second signal of the radiation that is generated by means of said first signal and is focused onto an associated receiver line 6, including the object element and crossing said transmitter line, in the object surface is received and an associated image information item is picked up therefrom; finally, the image is composed from the image information items of all the object elements.