Abstract: A thermoradiative device for generating power includes a thermoradiative element having a top surface and a bottom surface, wherein the thermoradiative element is a semiconductor material having a bandgap energy Eg. The device includes a thermal conductive element having a first surface and a second surface, wherein the first surface is arranged to face the bottom surface of the thermoradiative element, and the first surface is a structured surface having a periodic structure, wherein the structured surface is separated from the bottom surface with a distance d to establish near-field resonance between the bottom surface and the structured surface. The device further includes supporters configured to bond the thermoradiative element and the thermal conductive element.

Abstract: A thermophotovoltaic (TPV) energy converter includes a thermal emitter to generate photons of energy in response to receiving heat and a thermal receiver arranged at a distance from the thermal emitter. The thermal receiver includes a photovoltaic cell converting the received photons into electric energy. The thermal emitter includes a first layer of material arranged on a surface of the thermal emitter closest to the thermal receiver. The thermal receiver includes a second layer of material arranged on a surface of the thermal receiver closest to the thermal emitter. The first layer of material and the second layer of material have surface resonant frequencies above a bandgap of the photovoltaic cell.

Abstract: A radio frequency transmitter for wireless communication includes a plurality of input ports to receive a plurality of sequences of baseband symbols to be transmitted on a plurality of disjoint frequency bands, a power encoder to modulate and encode the plurality of sequences of baseband symbols to produce an encoded multi-band signal including the plurality of disjoint frequency bands carrying the plurality of sequences of baseband symbols, a first power amplifier for amplifying the encoded multi-band signal to produce an amplified encoded multi-band signal, a first noise canceller to generate a first noise mitigation signal from the encoded multi-band signal and the plurality of sequences of baseband symbols, a first power combiner to combine the amplified encoded multi-band signal and the first noise mitigation signal to produce an RF multi-band signal, and an antenna for transmitting the RF multi-band signal.

Abstract: A semiconductor device includes a semiconductor structure including a first doped layer for forming a carrier channel having a carrier charge, a second doped layer having a conductivity type identical to a conductivity type of the first doped layer, a barrier layer arranged in proximity to the semiconductor structure via the second doped layer, wherein the barrier layer includes a partially doped layer having a conductivity type opposite to the conductivity type of the second doped layer, and a set of electrodes for providing and controlling the carrier charge in the carrier channel.

Abstract: A thermal emitter including a substrate and a grating arranged atop the substrate, the grating includes a plurality of equidistant structures having a cross-section with a trapezoid shape. Material of the substrate and the grating converts incoming heat into radiation.

Abstract: A wideband power amplifier includes a set of amplifiers connected in parallel to amplify signals from input ports of the amplifiers, a matching network configured to match the signals amplified by the amplifiers with predetermined load values, the matching network having a first impedance frequency response as a monotonically decreasing function of frequency of the amplified signals in a target operation frequency range, a converter network configured to convert the signals matched by the matching network, and an impedance flattening network having a second impedance frequency response as a monotonically increasing function of frequency of the amplified signals in the target operation frequency range.

Abstract: A wideband power amplifier includes a set of amplifiers connected in parallel to amplify signals from input ports of the amplifiers, a matching network configured to match the signals amplified by the amplifiers with predetermined load values, the matching network having a first impedance frequency response as a monotonically decreasing function of frequency of the amplified signals in a target operation frequency range, a converter network configured to convert the signals matched by the matching network, and an impedance flattening network having a second impedance frequency response as a monotonically increasing function of frequency of the amplified signals in the target operation frequency range.

Abstract: A heat transfer device includes a layered structure having a first layer of a first material having a first thermal conductivity and a first thickness and a second layer of a second material having a second thermal conductivity and a second thickness, the second layer being connected to the first layer. In the layered structure, the first thermal conductivity is different from the second thermal conductivity, and wherein the first thickness is different from the second thickness.

Abstract: A semiconductor device includes a layered structure forming multiple carrier channels including at least one n-type channel formed in a first layer made of a first material and at least one p-type channel formed in a second layer made of a second material and a set of electrodes for providing and controlling carrier charge in the carrier channels. The first material is different than the second material, and the first and the second materials are selected such that the n-type channel and the p-type channel have comparable switching frequency and current capability.

Abstract: A sensor including a set of coils. The set of coils include a first coil and a second coil, wherein the first coil upon receiving energy, generates an electromagnetic near-field, such that the electromagnetic near-field provides at least a portion of the energy to the second coil through inductive coupling, inducing a current to pass through the set of coils. Further, a detector for measuring a voltage across at least one of the first coil or the second coil, wherein the detector includes a voltmeter. Finally, a processor for detecting a presence of a target structure in proximity to the set of coils upon detecting a change in a value of the voltage, wherein the target structure is an electromagnetic structure moving at a distance from the set of coils.

Abstract: A system includes a first resonator coupled to an energy source and a second resonator located a distance from the first resonator and coupled to the first resonator to provide near-field wireless energy transfer between the first resonator and the second resonator. The first resonator and the second resonator are non-radiative structures having a resonant frequency. The system also includes an artificial magnetic conductor (AMC) having the resonant frequency and arranged within the system to shape the near-field of at least one of the first resonator and the second resonator. The AMC includes a layer of unit cells arranged in a periodic pattern enabling the AMC to reflect the near-field. Each unit cell of the AMC includes a plurality of electronic components.

Abstract: A wideband self-envelope tracking power amplifier (PA) can use more than a 40-MHz channel bandwidth and improves the envelope bandwidth limit of a self-envelope tracking PAs by ten times. The PA uses an envelope load network, which is based on a general multi-stage low-pass filter. The envelope load network located between an RF choke inductor and main DC power supply provides a dynamically modulated PA supply voltage without using a dedicated envelope amplifier. An input terminal of the network connects a main PA via an RF choke inductor to an input of low-pass filter. An output terminal is connected to the low-pass filter via an envelope choke inductor and to a direct current (DC) power supply. A DC blocker is connected between the output of the low-pass filter and ground by a termination resistor.

Abstract: A semiconductor device includes a substrate, a back-barrier layer arranged on the substrate, the back-barrier layer including first p-type dopant atoms, an intermediate or nucleation layer having a lattice constant different from a lattice constant of the back-barrier layer, a semiconductor heterostructure having a channel layer, a spacer layer on the channel layer and a barrier layer on the spacer layer, wherein a combination of materials of the barrier layer, the spacer layer and the channel layer is selected such that a carrier charge is provided to the channel layer, a gate layer arranged to partially cover a top of the barrier layer, wherein the gate layer includes second p-type dopant atoms, and a set of electrodes for providing and controlling the carrier charge in the carrier channel.

Abstract: A power encoder includes a pulse width modulator for modulating a signal according to a set of thresholds to produce a pulse width modulated (PWM) signal and a switch mode power amplifier for amplifying the PWM signal by switching states of switching devices according to amplitudes of the PWM signal. At least one or combination of a distribution of values of the voltage thresholds in the set and a distribution of values of a current generated by different switching devices are non-uniform. The set of voltage thresholds includes at least two positive voltage thresholds.

Abstract: A method analyzes traps in a semiconductor device by determining a first-order derivative of a signal representing an operation of the semiconductor device over time to produce a signal rate change. The traps in the semiconductor device are analyzed based on lifetimes corresponding to peaks of the signal rate change.

Abstract: A semiconductor device includes a semiconductor structure forming a carrier channel, a barrier layer arranged in proximity with the semiconductor structure, and a set of electrodes for providing and controlling carrier charge in the carrier channel. The barrier layer is at least partially doped by impurities having a conductivity type opposite to a conductivity type of the carrier channel. The material of the barrier layer has a bandgap and thermal conductivity larger than a bandgap and thermal conductivity of material in the semiconductor structure.

Abstract: A method generates space vector modulation signals for a multi-level power inverter using space vector pulse width modulation (SVPWM). A reference voltage and a triangle region for the reference voltage are determined. Vertices for a space vector that is closest to the reference voltage is outputted. Then, the vertices are adjusted so that the space vector is in a valid region of the triangle region. Lastly, the space vector modulation signals a, b, and c corresponding to the space vector in the valid region are outputted.

Abstract: A semiconductor device includes a semiconductor structure forming a carrier channel, a barrier layer arranged in proximity with the semiconductor structure, and a set of electrodes for providing and controlling carrier charge in the carrier channel. The barrier layer is at least partially doped by impurities having a conductivity type opposite to a conductivity type of the carrier channel. The material of the barrier layer has a bandgap and thermal conductivity larger than a bandgap and thermal conductivity of material in the semiconductor structure.

Abstract: A semiconductor device includes a layered structure forming multiple carrier channels including at least one n-type channel formed in a first layer made of a first material and at least one p-type channel formed in a second layer made of a second material and a set of electrodes for providing and controlling carrier charge in the carrier channels. The first material is different than the second material, and the first and the second materials are selected such that the n-type channel and the p-type channel have comparable switching frequency and current capability.

Abstract: A three-way sequential power amplifier includes an input network connected to a main amplifier, a first peak amplifier, a second peak amplifier, which in turn are connected to a three-way output network. An input signal for an input port of the input network is a wideband radio frequency (RF) signal with a time varying amplitude. An output port of the output network can be connected to an antenna, via a bandpass filter, to attenuate out of band frequencies.