38results about How to "Low noise figure" patented technology

A high electron mobility transistor includes a substrate, a buffer layer, a channel layer, a spacer layer, a schottky layer and a cap layer. The buffer layer is formed on the substrate. The channel layer is formed on the buffer layer, in which the channel layer comprises a superlattice structure formed with a plurality of indium gallium arsenide thin films alternately stacked with a plurality of indium arsenide thin films. The spacer layer is formed on the channel layer. The schottky layer is formed on the spacer layer. The cap layer is formed on the schottky layer.

A RF device such as a tower mounted amplifier (TMA), mast-head amplifier (MHA), or Tower Mounted Boosters (TMB) includes a housing having a plurality of cavities and an input and an output, the input being coupled to the antenna and the output being coupled to a base station. The housing includes a transmission path holding multiple coaxial resonators. The housing further includes multiple receive paths including at least one path having a plurality of cavities, each cavity containing a dielectric resonator. The metallic transmit resonator nearest the antenna input is coupled to the first dielectric resonator via a common resonant wire. The last dielectric resonator in the receive path is coupled to a first metallic resonator of a downstream clean-up filter via another common resonant wire.

A method and apparatus are provided for reducing distortion in a dynamically delayed digital sample stream of an imaging system. The method includes the steps of delta-sigma modulating an input analog signal of the imaging system at a frequency above the Nyquist frequency of the input analog signal to generate a digital sample stream and changing a length of the sample stream to delay a portion of the sample stream while maintaining synchronism between a delta-sigma modulator and a demodulator of the system.

A radiometer includes a housing and an RF board carried by the housing. A hybrid and amplifier circuit receives an unknown signal and a known reference signal. A switch receives signals as inputs from the hybrid and amplifier circuit and switches between the inputs. A detection circuit receives and detects the signal from the switch forming a detected signal. A controller board is carried by the housing and an integration circuit and processor receive the detected signal and produces a digital output.

A wireless magnetic resonance imaging (MRI) scanner bore tube assembly has a radio frequency (RF) antenna, a microwave antenna array and an electrical screen. The RF antenna is formed of a series of RF antenna elements, each comprising a rung. The rungs are spaced at intervals of substantially half of the wavelength of the frequency of operation of the microwave antenna array. The microwave antenna array is formed by a series of microwave antenna elements interleaved between the rungs and the screen acts as a reflector to reflect signals from the microwave antenna elements towards the centre of the bore tube.

A CMOS differential power amplifier having broadband input matching with Noise and Non-linearity Cancellation. The broadband input match is realized by using two “Diode-Connected” NFETs (i.e., N-type Field Effect Transistors). Resulting noise degradation is reduced by using a noise cancellation structure. By using the same structure the disclosed method and apparatus also achieves non-linearity cancellation.

A negative-feedback type ultra-wideband signal amplification circuit is proposed, which is designed for integration to an ultra-wideband (UWB) signal processing circuit system for providing a low-noise amplification function to UWB signals. The proposed circuit architecture is characterized by the provision of a dual-step filter circuit on the input side, the provision of a resistive-type feedback circuit in the transistor-based amplification circuitry, and the provision of a common-source transistor-based amplification circuit on the output side. These features allow the proposed signal amplification circuit to have flat power gain, lower power consumption, low noise figure, and higher operational stability.

A radar system with a phase controlled antenna array that contains a number of data and supply networks (2), which are installed so that they are interchangeable, and a transmit / receive module (3) containing a transmitter and receiver circuit (4) as well as a number of circulator circuits (8) and a number of antenna elements (9) that are coupled via a circulator circuit (8) to the transmitter and receiver circuit (4). Transmitter and receiver circuits (4), circulator circuits (8), and antenna elements (9) are combined in each transmit / receive module (3) and the transmit / receive modules (3) are arranged interchangeably on the radiation side of the radar or EW system (1).

A RF device such as a tower mounted amplifier (TMA), mast-head amplifier (MHA), or Tower Mounted Boosters (TMB) includes a housing having a plurality of cavities and an input and an output, the input being coupled to the antenna and the output being coupled to a base station. The housing includes a transmission path holding multiple coaxial resonators. The housing further includes multiple receive paths including at least one path having a plurality of cavities, each cavity containing a dielectric resonator. The metallic transmit resonator nearest the antenna input is coupled to the first dielectric resonator via a common resonant wire. The last dielectric resonator in the receive path is coupled to a first metallic resonator of a downstream clean-up filter via another common resonant wire.

A wireless magnetic resonance imaging (MRI) scanner bore tube assembly has a radio frequency (RF) antenna, a microwave antenna array and an electrical screen. The RF antenna is formed of a series of RF antenna elements, each comprising a rung. The rungs are spaced at intervals of substantially half of the wavelength of the frequency of operation of the microwave antenna array. The microwave antenna array is formed by a series of microwave antenna elements interleaved between the rungs and the screen acts as a reflector to reflect signals from the microwave antenna elements towards the center of the bore tube.

A two port parametric amplifier has a first port that receives an input signal to be amplified and upconverted and a second port that receives a local oscillator signal. The amplified upconverted input signal is emitted as an output at upper and lower sideband frequencies. The amplifier further has a pair of varactor diodes connected between the first port and the second port. The diodes are connected in parallel from the first port and in series from the second port.

Provided is a frequency conversion mixer. The frequency conversion mixer includes a transconductance stage, a switching stage, a load stage, a current bleeding circuit, and a bias stage. The transconductance stage receives an RF signal, and outputs a current corresponding to a voltage of the RF signal. The switching stage switches the current which is outputted from the transconductance stage in response to a local oscillation signal, for frequency conversion the RF signal into an intermediate frequency (IF) signal. The load stage is connected between the switching stage and a supply voltage terminal. The current bleeding circuit is connected parallel with the switching stage, especially, embodying inverter structure with transconductance stage to get not only current bleeding effect but also current reuse effect, and one resonant inductor for reducing noise which is generated in parasitic capacitance at node between transconductance stage and switching stage. The bias stage is connected between the transconductance stage and a ground terminal, and has the switched biasing technique for allowing not only the stable bias current but also lowering the flicker noise.

A radiometer includes a housing and an RF board carried by the housing. A hybrid and amplifier circuit receives an unknown signal and a known reference signal. A switch receives signals as inputs from the hybrid and amplifier circuit and switches between the inputs. A detection circuit receives and detects the signal from the switch forming a detected signal. A controller board is carried by the housing and an integration circuit and processor receive the detected signal and produces a digital output.

The present disclosure relates to a front-end system for a radio device, the front-end system comprising a low-noise amplifier (LNA), arranged for receiving a radio frequency input signal (RFIN) and arranged for outputting an amplified radio frequency signal (RFOUT), wherein the low-noise amplifier comprises a first differential amplifier, and a mixer (MIX), arranged for down-converting the amplified radio signal (RFOUT) provided by the low-noise amplifier (LNA) to a baseband signal (BB), by multiplying the amplified radio signal (RFOUT) with a local oscillator (LO) frequency tone, said low-noise amplifier (LNA) and said mixer (MIX) being inductively coupled.

A vanadium oxide thermo-sensitive film material with a high temperature coefficient of resistance (TCR) contains a rare earth element of Yttrium serving as a dopant in a preparation process. The vanadium oxide thermo-sensitive film material includes a substrate and a yttrium-doped vanadium oxide film layer. The yttrium-doped vanadium oxide film layer includes three elements of vanadium, oxygen and yttrium, wherein the atomic concentration of yttrium is at a range of 1%-8%, the atomic concentration of vanadium is at a range of 20-40% and the residue is oxygen. The method for preparing the vanadium oxide thermo-sensitive film material with high TCR includes a reactive magnetron sputtering method using a low-concentration yttrium-vanadium alloy target as a sputtering source or a reactive magnetron co-sputtering method using dual targets including a high-concentration yttrium-vanadium alloy target and a pure vanadium target as a co-sputtering source.

The present disclosure relates to a front-end system for a radio device, the front-end system comprising a low-noise amplifier (LNA), arranged for receiving a radio frequency input signal (RFIN) and arranged for outputting an amplified radio frequency signal (RFOUT), wherein the low-noise amplifier comprises a first differential amplifier, and a mixer (MIX), arranged for down-converting the amplified radio signal (RFOUT) provided by the low-noise amplifier (LNA) to a baseband signal (BB), by multiplying the amplified radio signal (RFOUT) with a local oscillator (LO) frequency tone, said low-noise amplifier (LNA) and said mixer (MIX) being inductively coupled.

A re-configurable low noise amplifier utilizing feedback capacitors is disclosed. The low noise amplifier has output transistors, capacitor switch cells, and capacitance distributors all in an output portion. The output transistors are for controlling selection of a specific frequency band in a wide band of frequencies. The capacitor switch cells are for adjusting a harmonic frequency for the specific frequency band. The capacitance distributor is for determining an amount of gain, and according to the gain, an output impedance feeds back to an input portion of the low noise amplifier for input matching. Since the output portion is at high impedance and suitable for a wide band of frequencies, input matching not only makes the low noise amplifier applicable to kinds of wireless communication standards, but also fulfills high gain and low noise figure.

Improved lumped Raman amplification systems are disclosed. A lumped Raman amplification structure provides optimized efficiency, low noise figure over a range of gain settings, and a high saturation threshold. Responsibility for amplifying different portions of the spectrum is divided among multiple stages. In one particular implementation, two outer stages amplify a first band and two inner stages amplify a second band. The two inner stages also apply a small amount of amplification to the first band. A modification improves noise figure in the second band by adding some amplification in the second band to the first stage.

Embodiments of the present general inventive concept include a low noise amplifier and method with an improved linearity while reducing a noise disadvantage (e.g., increase). One embodiment of a low noise amplifier can include a first transistor to receive an input signal at a control terminal thereof, a second transistor having a first terminal coupled to a second terminal of the first transistor, an envelope detector to output a control signal corresponding to a characteristic of the input signal and an envelope amplifier to amplify the control signal to be applied to a control terminal of the second transistor.

The invention discloses an ultra wide band low noise amplifier with an active negative feedback structure, solves the problem that an existing low noise amplifier is relatively narrow in bandwidth andrelatively high in noise coefficient and has relatively high gain and good linearity. The low noise amplifier comprises an input amplifier module (1), an active negative feedback module (2) and an output amplifier module (3). According to the ultra wide band low noise amplifier, active negative feedback is introduced; an active inductor is formed through utilization of a source level follower; the bandwidth of a circuit is expanded by compensating high frequency band gain; the structure also has a noise cancellation effect; and a noise coefficient of the circuit is optimized. The linearity ofthe circuit is optimized by distributing a static current through the input amplifier module and the output amplifier module. The source level negative feedback is also introduced into an output endof the designed low noise amplifier, and the bandwidth of the circuit is further expanded. The ultra wide band low noise amplifier is simple in structure, easy to integrate and small in occupied area.

A receiver front end having low noise amplifiers (LNAs) with enhanced input third order intercept point is disclosed herein. A cascode having a “common source” configured input FET and a “common gate” configured load FET have a degeneration circuit comprising a tank circuit tuned to a harmonic of the operating frequency.

A CMOS differential power amplifier having broadband input matching with Noise and Non-linearity Cancellation. The broadband input match is realized by using two “Diode-Connected” NFETs (i.e., N-type Field Effect Transistors). Resulting noise degradation is reduced by using a noise cancellation structure. By using the same structure the disclosed method and apparatus also achieves non-linearity cancellation.

A high electron mobility transistor includes a substrate, a buffer layer, a channel layer, a spacer layer, a schottky layer and a cap layer. The buffer layer is formed on the substrate. The channel layer is formed on the buffer layer, in which the channel layer comprises a superlattice structure formed with a plurality of indium gallium arsenide thin films alternately stacked with a plurality of indium arsenide thin films. The spacer layer is formed on the channel layer. The schottky layer is formed on the spacer layer. The cap layer is formed on the schottky layer.

A RF device such as a tower mounted amplifier (TMA), mast-head amplifier (MHA), or Tower Mounted Boosters (TMB) includes a housing having a plurality of cavities and an input and an output, the input being coupled to the antenna and the output being coupled to a base station. The housing includes a transmission path holding multiple coaxial resonators. The housing further includes multiple receive paths including at least one path having a plurality of cavities, each cavity containing a dielectric resonator. The metallic transmit resonator nearest the antenna input is coupled to the first dielectric resonator via a common resonant wire. The last dielectric resonator in the receive path is coupled to a first metallic resonator of a downstream clean-up filter via another common resonant wire.

A low noise amplifier topology includes a dual gate transistor device, such as a HEMT device and employs resistive feedback with a DC block associated with the amplifier output to provide a desired high voltage gain and a low noise figure over a desired range of frequencies.

A negative-feedback type ultra-wideband signal amplification circuit is proposed, which is designed for integration to an ultra-wideband (UWB) signal processing circuit system for providing a low-noise amplification function to UWB signals. The proposed circuit architecture is characterized by the provision of a dual-step filter circuit on the input side, the provision of a resistive-type feedback circuit in the transistor-based amplification circuitry, and the provision of a common-source transistor-based amplification circuit on the output side. These features allow the proposed signal amplification circuit to have flat power gain, lower power consumption, low noise figure, and higher operational stability.

Embodiments of the present general inventive concept include a low noise amplifier and method with an improved linearity while reducing a noise disadvantage (e.g., increase). One embodiment of a low noise amplifier can include a first transistor to receive an input signal at a control terminal thereof, a second transistor having a first terminal coupled to a second terminal of the first transistor, an envelope detector to output a control signal corresponding to a characteristic of the input signal and an envelope amplifier to amplify the control signal to be applied to a control terminal of the second transistor.

A broadband optical amplifier for operation in the 2 μm visible wavelength band is based upon a single-clad Tm-doped fiber amplifier (TDFA). A compact pump source uses a combination of low-power laser diode with a fiber laser to provide a multi-watt pump beam without needing to include thermal management and / or pump wavelength stability components. The broadband optical amplifier is therefore able to be relatively compact device with fiber coupled output powers of >0.5 W CW, high small signal gain, low noise figure, and large OSNR, important for use as a versatile wideband preamplifier or power booster amplifier.