Abstract: A method and system for optical communication between a transmitter and receiver, using a video camera to image the location of the remote transmitter. The comparatively slow frame rate of conventional detector arrays, which would limit communication rate, is overcome by reading only pixels in a region of interest around the transmission source image, and these pixels can then be read out and the communication information on them retrieved, at a frame rate much faster than that of the conventional full frame read-out. Custom wiring of the array can be used to enable implementation of this increased frame rate. Other methods of increasing communication speed using a video camera array detector include spreading the optical signal spatially along a row of pixels, and reading those pixels simultaneously in one frame, or wavelength multiplexing the optical information, and dispersing the different wavelengths onto successive pixels of the array.

Abstract: There are provided a main beam direction determining device, a main beam direction determining method, and a program each of which is capable of shortening a time required for determination of a main beam direction of a head-mounted display. A secondary candidate sector selecting portion selects a part of a plurality of primary candidates as secondary candidates in response to a posture of an HMD. A sector level sweep processing executing portion determines a main beam direction of the HMD based on communication qualities when communications by the respective secondary candidates are performed from the secondary candidates.

Abstract: An apparatus and method for processing a frequency offset of a pilot and a receiver where the includes: calculating a correlation function of a channel by using a receiving or received signal and a correlation length; calculating a phase to which the correlation length corresponds according to the correlation function; and calculating a corresponding slope according to phases to which at least two correlation lengths correspond when the phase to which the correlation length corresponds is greater than 2?, and estimating a frequency offset of a pilot of the channel based on the slope. Hence, estimation of a frequency offset of a pilot may be accurately achieved, thereby accurately judging channel spacing.

Abstract: The present disclosure discloses a local oscillator feedthrough signal correction apparatus, including a microprocessor control unit, a first digital-to-analog converter, a second digital-to-analog converter, a mixer, a local oscillator, a signal output line, a signal splitter, and a detector tube. The signal splitter is disposed in the signal output line, and the first digital-to-analog converter and the second digital-to-analog converter are configured to provide the mixer with quadrature direct current components VI and VQ used for local oscillator feedthrough signal correction. The mixer outputs a local oscillator feedthrough signal to the signal output line. The signal splitter obtains the local oscillator feedthrough signal by means of splitting, and the detector tube detects the local oscillator feedthrough signal.

Abstract: A method and apparatus for communicating with a machine type communication user equipment (MTC UE) in a wireless communication system is provided. A base station (BS) configures a radio frame for the MTC UE based on a duration of a frequency hopping subframe group (FH-SFG), and communicates with the MTC UE by using the configured radio frame.

Abstract: Ultra-Wideband (UWB) technology exploits modulated coded impulses over a wide frequency spectrum with very low power over a short distance for digital data transmission. Today's leading edge modulated sinusoidal wave wireless communication standards and systems achieve power efficiencies of 50 nJ/bit employing narrowband signaling schemes and traditional RF transceiver architectures. However, such designs severely limit the achievable energy efficiency, especially at lower data rates such as below 1 Mbps. Further, it is important that peak power consumption is supportable by common battery or energy harvesting technologies and long term power consumption neither leads to limited battery lifetimes or an inability for alternate energy sources to sustain them. Accordingly, it would be beneficial for next generation applications to exploit inventive transceiver structures and communication schemes in order to achieve the sub nJ per bit energy efficiencies required by next generation applications.

Abstract: Audio video synchronization and alignment or alignment of audio to some other external clock are rendered more effective or easier by treating fragment grid and frame grid as independent values, but, nevertheless, for each fragment the frame grid is aligned to the respective fragment's beginning. A compression effectiveness lost may be kept low when appropriately selecting the fragment size. On the other hand, the alignment of the frame grid with respect to the fragments' beginnings allows for an easy and fragment-synchronized way of handling the fragments in connection with, for example, parallel audio video streaming, bitrate adaptive streaming or the like.

Abstract: Disclosed is a decoder circuit for a pulse amplitude modulation signal and a method of decoding a pulse amplitude modulation signal. The pulse amplitude modulation signal has a zeroth signal level, a first signal level, a second signal level and a third signal level. The decoder circuit comprises a first decision circuit, and a mapping circuit. The first decision circuit receives the pulse amplitude modulation signal and generates a low output signal for the first and the zeroth signal level, and generates a high output signal for the third and the second signal level. The mapping circuit receives the pulse amplitude modulation signal and generates a low output signal for the second and first signal level, and generates a high output signal for the third and zeroth signal level. Optionally, the decoder circuit comprises a logic circuit.

Abstract: A wavelength division multiplexed (WDM) reconfigurable optical switch, the switch has at least one optical input port to receive a WDM input optical signal comprising a plurality of wavelength channels; a plurality of optical output ports; a reconfigurable holographic array on an optical path between the at least one optical input port and the plurality of optical output ports; and at least one diffractive element on an optical path between at least one optical input port and the reconfigurable holographic array, to demultiplex the WDM input optical signal into a plurality of demultiplexed optical input beam channels, and to disperse the demultiplexed optical input beam channels spatially along a first axis on said the reconfigurable holographic array; and the switch further comprises one or more beam profiling optical elements to modify transverse beam profiles of the demultiplexed optical input beam channels.

Abstract: The present disclosure generally relates to optical modules, and in particular, to an optical module comprising a printed circuit board for reducing crosstalk between differential signal lines. In one implementation, the printed circuit board comprises a top layer, a first intermediate signal transmission layer, a second intermediate signal transmission layer, a bottom layer and multiple ground layers between signal transmission layers. Each signal transmission layer comprises one or more differential signal line pairs. The top layer and the bottom layer each comprises an edge connector, and the top layer further comprises a laser driver chip. The signal transmission layers are connected to the edge connectors and laser driver chips via a combination of blind and through connection holes such that the interference between the differential signal line pairs of various signal transmission layers are reduced.

Abstract: The present disclosure relates to radio engineering, and more specifically to high-frequency (HF) signal transmission/reception devices based on photoconductive switching elements. An HF signal transmission/reception device comprises a signal electrode with matching elements disposed along an edge thereof; a ground electrode, a dielectric layer between the signal electrode and the ground electrode, photoconductive elements (PE) each electrically connected to the signal electrode and the ground electrode and arranged in a grid, an excitation signal feed point, and load elements electrically connected to the matching elements. The photoconductive elements each have a switched-off state in the absence of a control light flux and a switched-on state in the presence of a control light flux, The switched-on photoconductive elements form a reflection profile of the signal supplied from the excitation signal feed point.

Abstract: Methods for use in a measurement system. Some embodiments comprise, at control unit, receiving a clock receive signal that represents a clock signal and configuration information; based on the clock receive signal, providing a control signal that represents the configuration information; and transmitting the control signal a sensor unit. Some embodiments comprise configuring the sensor unit according to the configuration information. Some embodiments comprise, at a control unit, configured to process data provided by the sensor unit. The method comprises receiving a data receive signal and selecting an interpretation of the data receive signal as one of at least: the sensor data signal and another data signal. Further disclosed herein are an interface, a control unit and a sensor unit for use in a measurement system.

Abstract: The present invention relates to an optical noise removal circuit, an optical receiver, and an optical chip. The optical noise removal circuit includes: a noise filter unit, where an input end of the noise filter unit receives an electrical signal coming from an photoelectric conversion unit, and the noise filter unit is configured to filter out a noise electrical signal, in the electrical signal, that is generated due to ambient light, and output a target pulse signal at an output end; and a comparison unit, where a first input end of the comparison unit is coupled to the output end of the noise filter unit to receive the target pulse signal, and the comparison unit is configured to output a digital signal based on comparison between the target pulse signal and a reference voltage. By implementing the present invention, quality of a received optical signal can be effectively improved.

Abstract: According to an embodiment, a transmission device is for a second quantum communication system sharing a quantum communication channel with a first quantum communication system, and includes a generator, a modulator, a controller, and a changer. The generator is configured to generate a photon. The modulator is configured to transmit a quantum signal generated by modulating the photon to a reception device. The controller is configured to control the generator and the modulator. The changer is configured to input, to the controller, control signals for changing an operation timing of the generator and an operation timing of the modulator when an error rate of the quantum signal of the first quantum communication system and an error rate of the quantum signal of the second quantum communication system are equal to or higher than a predetermined threshold.

Abstract: Methods and apparatus for vector quantization of feedback and processing of vector quantized feedback components. A method of operating a UE for vector quantization of feedback includes identifying a grouping method for grouping channel coefficients for vector quantization and identifying a vector quantization codebook for vector quantization of grouped vectors based on one or more control signals received from an eNB. The method includes computing channel coefficients based on at least one channel measurement and grouping the computed channel coefficients according to the identified grouping method to form a set of vectors. The method also includes performing vector quantization of the vectors using the identified vector quantization codebook and processing the quantized vectors into one or more feedback signals. Additionally, the method includes transmitting the one or more feedback signals to the eNB.

Abstract: In certain embodiments, a system for transmitting (electromagnetic or acoustic) wave-based signals towards a target includes a plurality of transceivers and a controller. Each transceiver transmits a probe signal towards the target and receives an associated backscatter signal corresponding to reflection of the probe signals from the target. The controller determines, for each transceiver, a Doppler frequency shift and a time delay, modifies each associated backscatter signal based on the corresponding Doppler frequency shift and time delay to generate an associated motion-compensated backscatter signal, and applies time reversal (TR) processing to each motion-compensated backscatter signal to generate an associated motion-compensated TR signal. Each transceiver transmits towards the target a transmission signal based the associated motion-compensated TR signal. In communications systems, the transmission signals are data-modulated versions of the motion-compensated TR signals.

Abstract: The present invention relates to an image sensor communication (ISC) system and method for enabling communication between an LED and a rolling shutter camera using a rolling shutter modulation method. The image sensor communication system according to an embodiment of the present invention comprises: a coding unit for coding transmission data to be transmitted; an LED which is turned on/off according to the transmission data coded in the coding unit; a rolling shutter camera for continuously photographing, at each of a plurality of rows in a rolling shutter manner, on/off images according to the on/off of the LED; an image processing unit for generating brightness signals according to brightness values of the on/off images of the LED photographed at each of the plurality of rows by the rolling shutter camera; and a data extraction unit for extracting the transmission data from the brightness signals of the on/off images of the LED generated by the image processing unit.

Abstract: The systems and methods disclosed herein are generally directed to the real-time modification of symbol rates, during modulation, based on performance metrics such as noise and traffic levels. In one embodiment, machine learning algorithms may be used to determine programmatically expected channel conditions and, in turn, an optimized symbol rate. In one embodiment, adaptive bit loading can be used such that a lower order modulation scheme can be used to overcome the noise and increase the signal-to-noise ratio (SNR) of the transmitted signal. In one embodiment, more throughput (for example, more bps/Hz) can be achieved in the network by using subcarriers that have a higher SNR. Further, the bit loading can serve to maximize the data rate subject to the power and bit error ratio (BER) constraints of the network. In one embodiment, the machine learning algorithms may dynamically change the symbol rate of modulation to enhance the network performance.

Abstract: The present application discloses a reconfigurable transmitter and receiver, and methods for reconfiguring the same. A system adaptive control circuit generates a control signal according to frequency band information of an input signal; a system clock circuit generates a system clock; a preprocessing circuit preprocesses a received baseband signal according to the system clock and the control signal, to generate a frequency band signal; a digital intermediate frequency processing circuit processes the frequency band signal according to the system clock and the control signal, to generate a digital intermediate frequency signal; a digital-to-analog conversion circuit processes the digital intermediate frequency signal according to the system clock and the control signal, to generate an analog signal; and an analog transmitting circuit transmits the analog signal.

Abstract: Methods, devices and computer programs for determining new transmit directions to use for beamformed transmissions in case the link quality of an existing direction falters. A transmitting communication device and a receiving communication device cooperate via a beam tracking procedure to determine a new suitable transmit direction to use for upcoming beamformed transmissions. Information relating to the beam tracking procedure is communicated over an existing link that enables communication between the transmitting and receiving communication devices. The receiving communication device provides the transmitting communication device with information about a beam scan performed in order to detect tracking beams transmitted by the transmitting communication device. This information allows the transmitting communication device to determine suitable transmit directions to use.