Abstract: Structures with doping free connections and methods of fabrication are provided. An exemplary structure includes a substrate; a first region of a first conductivity type formed in the substrate; an overlying layer located over the substrate; a well region of a second conductivity type formed in the overlying layer; a conductive plug laterally adjacent to the well region and extending through the overlying layer to electrically contact with the first region; and a passivation layer located between the conductive plug and the well region.

Abstract: In some embodiments, the present disclosure relates to a single-photon avalanche detector (SPAD) device including a silicon substrate including a recess in an upper surface of the silicon substrate. A p-type region is arranged in the silicon substrate below a lower surface of the recess. An n-type avalanche region is arranged in the silicon substrate below the p-type region and meets the p-type region at a p-n junction. A germanium region is disposed within the recess over the p-n junction.

Abstract: An optical signal transmitter system in an optical communication network includes a digital pre-emphasis device structured to generate a pre-emphasized digital data signal by pre-emphasizing at least a portion of a digital data signal to be transmitted, a digital-to-analog converter coupled to the digital pre-emphasis device to convert the pre-emphasized digital data signal into an analog data signal, an analog pre-emphasis device coupled to the digital-to-analog converter to generate a pre-emphasized analog data signal by pre-emphasizing at least a portion of the analog data signal, an electrical-to-optical converter to convert the pre-emphasized analog signal into an optical signal, and a processor configured to determine a pre-emphasis assignment distribution between the digital pre-emphasis device and the analog pre-emphasis device.

Abstract: Methods, systems and devices for reducing pattern effects in pulse amplitude modulation (PAM) signals in semiconductor optical amplifiers (SOAs) are described. One method for digital communication includes generating, based on (2M+1) N-level PAM (PAM-N) symbols, an index corresponding to an entry of a look-up table (LUT) that comprises adjustment values, wherein M and N are integers, determining, based on the index, a selected adjustment value from the LUT, generating a pre-distorted PAM-N symbol based on a difference between a center symbol of the (2M+1) PAM-N symbols and the selected adjustment value, and generating, using an SOA, a waveform that includes the pre-distorted PAM-N symbol.

Abstract: An angle-adjusting mechanism is provided. The angle-adjusting mechanism includes a reflecting assembly, a transmission assembly and a driving unit. The reflecting assembly includes a reflecting plate. The transmission assembly includes a transmission rod and a connecting element disposed on the transmission rod. The transmission assembly is connected to the reflecting assembly via the connecting element. The driving unit is configured to drive the transmission rod to move the reflecting assembly.

Abstract: An optical transmitter apparatus is disclosed. The apparatus includes a processor, a memory coupled to the processor, and one or more programs configured to be executed by the processor. The programs include instructions for nonlinearity estimation that characterizes nonlinearity in an optical communication and estimates an amount of symbol distortion caused by the nonlinearity, instructions for selecting and mapping symbols to provide, for the nonlinearity estimation, only symbols that meet predetermined nonlinearity criteria, and instructions for storing, in the memory, the amount of symbol distortion to be used for a nonlinearity pre-compensation.

Abstract: An optical receiver apparatus includes a photo detector that detects amplitude modified optical signals transmitted through an optical transmission channel and mapped to constellation points and converts the optical signal into electrical signals, a sampling circuit that samples the electrical signals and generates digital signals, and a signal processing circuit that has a two-step equalization algorithm converging actual constellation points into desired constellation points. The two-step equalization algorithm includes a first equalization algorithm that uses multiple modulus in performing an error signal calculation, and a second equalization algorithm that includes a filtering procedure that compares actual constellation points with desired constellation points and an adjustment procedure that iteratively adjusts parameters of the filtering procedure in accordance with the comparison result.

Abstract: A method of generating a probabilistically shaped (PS), multi-level modulation signals includes encoding information bits into coded bits to which probability values are assigned according to a probability mass function, and mapping, based on a Gray coding scheme, the coded bits into symbols to which the probability values are assigned. The probability mass function is implemented by determining probabilities of the coded bits so that the probabilities of the coded bits in ascending or descending order have a Gaussian distribution, and performing a probability distribution pre-adjustment by redistributing probabilities of the coded bits corresponding to symbols probabilities of which are outside Gaussian distribution so that the symbols mapped based on the Gray coding scheme have the Gaussian distribution.

Abstract: A method of generating a probabilistically shaped (PS), multi-level modulation signals includes encoding information bits into coded bits to which probability values are assigned according to a probability mass function, and mapping, based on a Gray coding scheme, the coded bits into symbols to which the probability values are assigned. The probability mass function is implemented by determining probabilities of the coded bits so that the probabilities of the coded bits in ascending or descending order have a Gaussian distribution, and performing a probability distribution pre-adjustment by redistributing probabilities of the coded bits corresponding to symbols probabilities of which are outside Gaussian distribution so that the symbols mapped based on the Gray coding scheme have the Gaussian distribution.

Abstract: An angle-adjusting mechanism is provided. The angle-adjusting mechanism includes a reflecting assembly, a transmission assembly and a driving unit. The reflecting assembly includes a reflecting plate. The transmission assembly includes a transmission rod and a connecting element disposed on the transmission rod. The transmission assembly is connected to the reflecting assembly via the connecting element. The driving unit is configured to drive the transmission rod to move the reflecting assembly.

Abstract: An optical transmitter apparatus is disclosed. The apparatus includes a processor, a memory coupled to the processor, and one or more programs configured to be executed by the processor. The programs include instructions for nonlinearity estimation that characterizes nonlinearity in an optical communication and estimates an amount of symbol distortion caused by the nonlinearity, instructions for selecting and mapping symbols to provide, for the nonlinearity estimation, only symbols that meet predetermined nonlinearity criteria, and instructions for storing, in the memory, the amount of symbol distortion to be used for a nonlinearity pre-compensation.

Abstract: An optical receiver apparatus includes a photo detector that detects amplitude modified optical signals transmitted through an optical transmission channel and mapped to constellation points and converts the optical signal into electrical signals, a sampling circuit that samples the electrical signals and generates digital signals, and a signal processing circuit that has a two-step equalization algorithm converging actual constellation points into desired constellation points. The two-step equalization algorithm includes a first equalization algorithm that uses multiple modulus in performing an error signal calculation, and a second equalization algorithm that includes a filtering procedure that compares actual constellation points with desired constellation points and an adjustment procedure that iteratively adjusts parameters of the filtering procedure in accordance with the comparison result.

Abstract: Methods and apparatus to realize high spectral efficiency in optical signals transmitted over long distances.

Abstract: A technique for optical signal transmission includes generating a plurality of double sideband modulated optical signals by modulating a plurality of source data signals using a plurality of direct modulation laser (DML) optical sources, wherein the plurality of double sideband modulated optical signals occupy non-overlapping neighboring optical frequency bands, generating a chirp-managed laser (CML) output signal by multiplexing the plurality of double sideband modulated optical signals using a wavelength-selective multiplexer, and transmitting the CML output signal over an optical transport medium.

Abstract: An electronic device includes a motor, a gear set, a meter frame set, a first screw rod, and a second gear rack. The gear set is driven by the motor and includes a first gear. The meter frame set includes a first gear rack extending along an arc line and adapted to be engaged with the first gear of the gear set. When the motor is operated and the first gear rack is engaged with the first gear, the first gear drives the first gear rack such that the meter frame set moves along the arc line. The first screw rod is linked with the gear set and extends along a first axis. The second gear rack is adapted to be linked with the meter frame set. When the motor is operated and the second gear rack is engaged with the first screw rod, the first gear rack is not engaged with the first gear, and the meter frame set is linked with the second gear rack to move along the first axis with the second gear rack.

Abstract: A scheme for generating asymmetric single sideband photonic vector signal at millimeter wave spectral region is described. At a transmitter, information bits to be transmitted are modulated using a vector modulation technique to generate a baseband signal. The baseband signal is converted into its single sideband (SSB) version using a complex frequency source having a first frequency. The real part of the upconverted signal is added to the real part of a second frequency source and is input as I component to an I/Q modulator. The imaginary part of the upconverted signal is added to the imaginary part of the second frequency source and is used as the Q component. The I/Q modulator is driven by a laser source at frequency fc. The resulting signal is transmitter over an optical transmission medium and upconverted by a single-ended photodiode to a desired radio-frequency (RF) carrier frequency.

Abstract: A method of optical communication, implemented at a receiver in an optical communication network, includes receiving an optical signal carrying modulated information bits, processing the optical signal through a receiver subsystem to generate a stream of digitized modulation symbols from the optical signal, and producing, using the digitized modulation symbols as input symbols to an iterative process, estimates of information bits. Each iteration includes: generating estimated output symbols from input symbols by filtering by an estimate of inverse of the optical channel, updating, using the estimated output symbols, the estimate of the inverse of the optical channel to minimize a measure of error, and compensating the estimated output symbols by using pre-distortion values from a look-up table (LUT) to generate compensated output symbols that are used as input to a next iteration.

Abstract: Throughput between a transmitter and a receiver is increased by performing a three-stage joint channel optimization in which training sequences are used for calculating a pre-equalization estimate in the first stage, a look up table for pre-distortion in the second stage and a further updating the pre-equalization estimate and the look up table based on a third stage in which the training sequence used for the updating is pre-equalized and pre-distorted using previously calculated values prior to transmitting from the transmitter to the receiver.

Abstract: A display device includes a display panel, at least one touch sensor, a touch sensor controller and a display controller. The at least one touch sensor senses and outputs a touch sensing signal. The touch sensor controller, electrically coupled to the touch sensor, receives the touch sensing signal and generates a touch sensing result accordingly. The display controller, electrically coupled to the display panel and the touch sensor controller, receives graphic data to generate first display data and determines whether to adjust the first display data to second display data and transmit the second display data to the display panel according to the touch sensing result. The first display data has first display a feature, the second display data has a second feature, and the first display feature is different from the second display feature. An operating method of the display device is also provided.

Abstract: Methods and apparatus to realize high spectral efficiency in optical signals transmitted over long distances.