Abstract: The present disclosure relates to compensating for temperature variation of a mixer. Embodiments herein may include the mixer, a calibration circuit coupled to the mixer, a replica mixer circuit coupled to the calibration circuit, and a temperature compensation circuit coupled to the calibration circuit. The replica mixer circuit may generate or be used to generate a reference voltage that varies with a common mode voltage and/or a threshold voltage of a replica mixer. The reference voltage may be applied to a resistor ladder of the calibration circuit to adjust a bias voltage and compensate for temperature variations. Further, the temperature compensation circuit may generate a temperature coefficient that may be applied to a current going through the calibration circuit to facilitate compensating for temperature variation.

Abstract: Some embodiments of the disclosure provide a fluorescent composite particle. In some examples, the fluorescent composite particle includes a fluorescent material having a plurality of fluorescent nanocrystals, and an oxide material. The fluorescent material is densely coated with the oxide material, and a molar ratio of the fluorescent material to the oxide material is 10:1 to 1:100. The fluorescent composite particle has a particle size of 20 nm to 500 nm, a density of 1.8 g/cm3 to 7 g/cm3, and a specific surface area of 8 m2/g to 200 m2/g. According to some embodiments of the present disclosure, the fluorescent composite particle having high stability and small particle size may be provided. Moreover, the present disclosure further provides two preparation methods for obtaining a fluorescent composite particle having a predetermined morphology.

Abstract: A switched capacitor circuit is provided that may include a first capacitor, a second capacitor, one or more switches coupled between the first and second capacitors, and a first output switch coupled between the first capacitor and a first output terminal. The one or more switches can be controlled by a first pulse signal, and the first output switch can be controlled by a second pulse signal different than the first pulse signal. The switched capacitor circuit can further include a second output switch coupled between the second capacitor and a second output terminal different than the first output terminal. The second output switch can also be controlled by the second pulse signal. The second pulse signal can overlap only a portion of the first pulse signal.

Abstract: The present disclosure relates to compensating for temperature variation of a mixer. Embodiments herein may include the mixer, a calibration circuit coupled to the mixer, a replica mixer circuit coupled to the calibration circuit, and a temperature compensation circuit coupled to the calibration circuit. The replica mixer circuit may generate or be used to generate a reference voltage that varies with a common mode voltage and/or a threshold voltage of a replica mixer. The reference voltage may be applied to a resistor ladder of the calibration circuit to adjust a bias voltage and compensate for temperature variations. Further, the temperature compensation circuit may generate a temperature coefficient that may be applied to a current going through the calibration circuit to facilitate compensating for temperature variation.

Abstract: A method, system and apparatus for reconfigurable intelligent surface-assisted energy-efficient radio access networks using hierarchical reinforcement learning are disclosed. A method in a network node operating as a meta-controller and configured to communicate with a wireless device and a plurality of sub-controllers is provided. The method includes determining a state of the meta-controller including traffic load ratios of the plurality of sub-controllers. The method also includes receiving an extrinsic reward that is based on an energy efficiency of a cell including the plurality of sub-controllers. The method further includes selecting a goal according to a policy, the selected goal being an on/off state of each of the plurality of sub-controllers, the policy being selected to increase the extrinsic reward. The method includes configuring the plurality of controllers with the selected goal and an indication of the policy for selecting the goal.

Abstract: The present disclosure relates to compensating for temperature variation of a mixer. Embodiments herein may include performing a single-point Fast Fourier Transform (FFT) (or complex downconversion with DC average) for a number of samples to obtain a transform for each of the number of samples, phase aligning a set of phases associated with each transform, and averaging each transform to generate an analog-to-digital converter (ADC) power value. Further, the disclosed embodiments may include generating a compensation value based on the analog-to-digital converter power value and applying the compensation value to the calibration circuit of the mixer to compensate for a second-order intermodulation product.

Abstract: A signal transmitter may include a waveform synthesis circuit and a signal transmission circuit. The waveform synthesis circuit may store values of a reference waveform for a selected channel of the signal transmitter, and use the stored values to generate values of reference waveforms for one or more other channels of the signal transmitter. The waveform synthesis circuit may further include a sampling boost circuit to generate one or more additional values for the reference waveforms. The waveform transmission circuit may generate signals for the channels of the signal transmitter based at least in part on the values of the reference waveforms, and transmit the signals via one or more antennas.

Abstract: Embodiments herein provide various apparatuses and techniques to reduce flicker noise and voltage offset from the buffers and/or amplifiers while avoiding additional alias components in a sampled-data receiver with chopper stabilization. Additionally, a direct-conversion baseband chain may be improved by disposing alternating current (AC) coupling circuits between chopper circuits in the transmitter or receiver chain to enable selection of a distinct common-mode level at each stage of the direct-conversion chain, while reducing or eliminating signal loss at direct current (DC) frequencies.

Abstract: Embodiments herein provide various apparatuses and techniques to reduce flicker noise and voltage offset from the buffers and/or amplifiers while avoiding additional alias components in a sampled-data receiver with chopper stabilization. Additionally, a direct-conversion baseband chain may be improved by disposing alternating current (AC) coupling circuits between chopper circuits in the transmitter or receiver chain to enable selection of a distinct common-mode level at each stage of the direct-conversion chain, while reducing or eliminating signal loss at direct current (DC) frequencies.

Abstract: The present disclosure relates to compensating for temperature variation of a mixer. Embodiments herein may include the mixer, a calibration circuit coupled to the mixer, a replica mixer circuit coupled to the calibration circuit, and a temperature compensation circuit coupled to the calibration circuit. The replica mixer circuit may generate or be used to generate a reference voltage that varies with a common mode voltage and/or a threshold voltage of a replica mixer. The reference voltage may be applied to a resistor ladder of the calibration circuit to adjust a bias voltage and compensate for temperature variations. Further, the temperature compensation circuit may generate a temperature coefficient that may be applied to a current going through the calibration circuit to facilitate compensating for temperature variation.

Abstract: The present disclosure relates to compensating for temperature variation of a mixer. Embodiments herein may include performing a single-point Fast Fourier Transform (FFT) (or complex downconversion with DC average) for a number of samples to obtain a transform for each of the number of samples, phase aligning a set of phases associated with each transform, and averaging each transform to generate an analog-to-digital converter (ADC) power value. Further, the disclosed embodiments may include generating a compensation value based on the analog-to-digital converter power value and applying the compensation value to the calibration circuit of the mixer to compensate for a second-order intermodulation product.

Abstract: A signal transmitter may include a waveform synthesis circuit and a signal transmission circuit. The waveform synthesis circuit may store values of a reference waveform for a selected channel of the signal transmitter, and use the stored values to generate values of reference waveforms for one or more other channels of the signal transmitter. The waveform synthesis circuit may further include a sampling boost circuit to generate one or more additional values for the reference waveforms. The waveform transmission circuit may generate signals for the channels of the signal transmitter based at least in part on the values of the reference waveforms, and transmit the signals via one or more antennas.

Abstract: A signal transmitter may include a waveform synthesis circuit and a signal transmission circuit. The waveform synthesis circuit may store values of a reference waveform for a selected channel of the signal transmitter, and use the stored values to generate values of reference waveforms for one or more other channels of the signal transmitter. The waveform synthesis circuit may further include a sampling boost circuit to generate one or more additional values for the reference waveforms. The waveform transmission circuit may generate signals for the channels of the signal transmitter based at least in part on the values of the reference waveforms, and transmit the signals via one or more antennas.

Abstract: A multibeam antenna including a substrate, and further includes an antenna element, a first guiding apparatus, and a second guiding apparatus disposed on the substrate. The antenna element includes a first pole configured to receive a feeding signal and a second pole that is grounded. The first guiding apparatus enables a first beam generated by the antenna element to radiate in a first direction, and the second guiding apparatus enables a second beam generated by the antenna element to radiate in a second direction. A phase center of the antenna element is at an intersecting point of a first axis and a second axis, the first axis passing through a phase center of the first guiding apparatus and parallel to the first direction, and the second axis passing through a phase center of the second guiding apparatus and parallel to the second direction.

Abstract: A signal transmitter may include a waveform synthesis circuit and a signal transmission circuit. The waveform synthesis circuit may store values of a reference waveform for a selected channel of the signal transmitter, and use the stored values to generate values of reference waveforms for one or more other channels of the signal transmitter. The waveform synthesis circuit may further include a sampling boost circuit to generate one or more additional values for the reference waveforms. The waveform transmission circuit may generate signals for the channels of the signal transmitter based at least in part on the values of the reference waveforms, and transmit the signals via one or more antennas.

Abstract: An electronic device may include wireless circuitry with processor circuitry, a transceiver circuit, a front-end module, and an antenna. The front-end module may include amplifier circuitry such as low noise amplifier circuitry for amplifying received radio-frequency signals. The amplifier circuitry may include an amplifier having an input and an output, an adjustable load component coupled to the input, and an adjustable feedback component coupled across the input and output. A control circuit may simultaneously adjust the load and feedback components to tune the gain of the amplifier circuitry while maintaining the input resistance at a desired target level. The load and feedback components can be the same or different types of adjustable passive components.

Abstract: An electronic device may include wireless circuitry with processor circuitry, a transceiver circuit, a front-end module, and an antenna. The front-end module may include amplifier circuitry such as low noise amplifier circuitry for amplifying received radio-frequency signals. The amplifier circuitry may include an amplifier having an input and an output, an adjustable load component coupled to the input, and an adjustable feedback component coupled across the input and output. A control circuit may simultaneously adjust the load and feedback components to tune the gain of the amplifier circuitry while maintaining the input resistance at a desired target level. The load and feedback components can be the same or different types of adjustable passive components.

Abstract: A multibeam antenna including a substrate, and further includes an antenna element, a first guiding apparatus, and a second guiding apparatus disposed on the substrate. The antenna element includes a first pole configured to receive a feeding signal and a second pole that is grounded. The first guiding apparatus enables a first beam generated by the antenna element to radiate in a first direction, and the second guiding apparatus enables a second beam generated by the antenna element to radiate in a second direction. A phase center of the antenna element is at an intersecting point of a first axis and a second axis, the first axis passing through a phase center of the first guiding apparatus and parallel to the first direction, and the second axis passing through a phase center of the second guiding apparatus and parallel to the second direction.

Abstract: This application provides implementations related to lenses. In one implementation, a lens comprises a substrate layer and a metal layer, wherein at least one surface of the substrate layer is a concave surface or a convex surface; the metal layer exists on the at least one surface of the substrate layer; the metal layer comprises a metal part and a hollow-out part, and the metal part or the hollow-out part is presented by using a graphics array; the graphics array comprises a plurality of first rings, the first ring comprises a plurality of graphic units, and a larger ring encircles a smaller ring in the plurality of first rings; and at least one of the following are different: size of graphic units comprised in two adjacent first rings, rotation angle of graphic units comprised in two adjacent first rings, or two adjacent first intervals, wherein the first interval is an interval between the two adjacent first rings.

Abstract: A computer system may periodically calibrate an oscillator subsystem, which includes a voltage-controlled oscillator circuit configured to generate an oscillator signal using code signal. In response to activation of a calibration mode, an iterative calibration operation may be performed on the voltage-controlled oscillator circuit. In some cases, performing a given iteration of the calibration operation includes determining a value of the code signal using a number of pulses in the oscillator signal sampled during a particular time period, along with previous values of the code signal and a slope of an error function associated with the difference between a desired frequency and a current frequency of the oscillator signal. In other cases, iterations may employ variable sampling times with error handling, in order to decrease the duration of the calibration operation while maintaining a target accuracy.