128 results about "Distributed amplifier" patented technology

A device for decoupling a supply voltage for HF amplifier circuits is described which includes an output line for coupling out an amplified signal, wherein one end of the output line, which is not used for coupling out signals, is connected to a circuit element designed as decoupling circuit. The circuit element has a low ohmic d.c. resistance and presents an HF-power absorption capacity that increases as the frequency increases, thus constituting a reflection-free termination for high frequencies. The circuit element is preferably constituted by several discrete subcircuits connected in succession. The device permits the operation of integrated distributed amplifiers of high performance at a low power loss caused by the decoupling circuit.

A resistive level-shifting biasing network is used with a capacitor in parallel to couple FET-based amplifier stages from DC to several GHz in a multi-stage amplifier. The output of the first amplifier stage is connected to the input of the second amplifier stage without a blocking capacitor or level-shifting diodes, allowing a portion of the drain current for the first amplifier stage to be supplied from the second amplifier stage. In a particular embodiment, a distributed amplifier achieved over 20 dB gain from DC to about 80 GHz using three traveling wave amplifier chips.

High speed optical modulators can be made of k modulators connected in series disposed on one of a variety of semiconductor substrates. An electrical signal propagating in a microwave transmission line is tapped off of the transmission line at regular intervals and is amplified by k distributed amplifiers. Each of the outputs of the k distributed amplifiers is connected to a respective one of the k modulators. Distributed amplifier modulators can have much higher modulating speeds than a comparable lumped element modulator, due to the lower capacitance of each of the k modulators. Distributed amplifier modulators can have much higher modulating speeds than a comparable traveling wave modulator, due to the impedance matching provided by the distributed amplifiers.

The image sensor makes use of a distributed amplifier having its non-inverting input provided by a pixel amplifier transistor, and its inverting input and output provided in the pixel's column circuitry. The distributed amplifier is directly integrated with the image sensor's ADC circuit, and sampling and autozero are performed in a single step, thus reducing the number of noise contributions made by the components of the image sensor's readout chain.

A distributed amplifier uses non-uniform filtering structures to provide better control over pass-band and stop-band characteristics. The various sections can have different tap coefficients. A notch filter can be implemented for interference suppression or pulse shaping in an ultra-wideband transceiver.

A number of identical non-uniformly distributed ultra-wideband power amplifier string building blocks are coupled together to form an ultra-wide bandwidth high-power amplifier. The non-uniform distribution results in an amplifier utilizing modular string building blocks that have input and output impedances with only real values. This permits the strings to be replicated and connected together with simple impedance matching. The internal impedance matching associated with the non-linear distribution also absorbs parasitic capacitance to permit the ultra-broadband operation. In one embodiment identical transistors are used for each cell so that the strings may be identically replicated. This permits modular re-use without reconfiguration. In one embodiment a non-uniform distributed power amplifier built using the subject building blocks provides an ultra-wideband multi-octave device suitable for electronic warfare and communications applications, especially to replace traveling wave tubes.

A distributed amplifier with improved stabilization includes an input transmission circuit, an output transmission circuit, at least one cascode amplifier coupled between said input and output transmission circuits. Each cascode amplifier includes a common-gate configured transistor coupled to the output transmission circuit, and a common-source configured transistor coupled between the input transmission circuit and the common-gate configured transistor. The distributed amplifier also includes a non-parasitic resistance and capacitance coupled in series between a drain and a gate of at least one of the common-gate configured transistors for increasing the amplifier stability.

A distributed amplifier system has a predetermined output impedance and input impedance and includes an input transmission circuit; an output transmission circuit; at least two amplifiers connected between the input and output transmission circuits; an input termination on the input transmission circuit; and a feedback output termination on the output transmission circuit connected back to the input transmission circuit for reducing low frequency loss while maintaining the predetermined output impedance and input impedance.

A wideband distributed or feedback amplifier monolithic microwave integrated circuit (MMIC) is disclosed that contains an integrated group delay equalizer circuit to compensate for the group delay variation of the amplifier circuitry. The MMIC amplifier is capable of achieving a predicted constant group delay with little variation over a wide frequency range. In addition, the group delay equalizer circuit enables the amplifier to achieve flat (constant) gain over a wide bandwidth, while maintaining constant group delay. Furthermore, the group delay equalizer circuitry requires only a small portion of the total MMIC area.