Abstract: An adaptive equalizer includes: a speculative equalization circuit which operates a plurality of first tap coefficients with respect to input data and selects operation data corresponding to the input data from a plurality of operation data obtained by the operation; and an adaptive equalization circuit which generates the plurality of first tap coefficients, on the basis of the input data.

Abstract: A method includes receiving data units each having a preamble with first and second preamble portions, detecting symbol constellation rotations of OFDM symbols in the first preamble portions, and determining, based on the detected rotations, whether the preambles conform to a first format. The method also includes, when it is determined that a preamble conforms to the first format, processing the second preamble portion according to the first format, and, when it is determined that a preamble does not conform to the first format, (i) determining whether information bits in the first preamble portion indicate a single- or multi-user data unit, (ii) when it is determined that the information bits indicate a single-user data unit, processing the second preamble portion according to a second format, and (iii) when it is determined that the information bits indicate a multi-user data unit, processing the second preamble portion according to a third format.

Abstract: The present disclosure provides a method and apparatus for transmitting a common signal in hybrid beamforming. The method includes: acquiring an analog common signal to be transmitted; selecting a different codeword for each RF chain from a codebook for analog beamforming and obtaining an analog beamformer; beamforming the analog common signal to be transmitted in each RF chain according to the analog beamformer; and transmitting the beamformed analog common signal in each RF chain.

Abstract: A method of rejecting impulsive noise in an OFDM receiver is described. The impulsive noise is rejected using channel state information (CSI) and is performed in the frequency domain. A noise power estimate (furthermore referred to as a noise value) is measured for a single OFDM symbol and compared to a threshold value, which may be generated based on a short-term average of OFDM symbols not corrupted by impulsive noise or predicted based on a small number of previously measured OFDM symbols not corrupted by impulsive noise. If the noise estimate for the particular OFDM symbol exceeds the threshold value, the CSI for that symbol is derated (i.e. modified) to reduce the influence of the information from this symbol on the decoding process.

Abstract: A slicer apparatus and a calibration method thereof are provided. A differential reference signal pair used for performing an error slicing operation is adjusted, so as to calibrate an offset voltage of the slicer apparatus.

Abstract: In a coherent receiver of an optical communication system, a method of processing a detected symbol estimate to determine a most likely value of a corresponding transmitted data word, the transmitted data word comprising one or more data bits encoded in a transmitter using a predetermined constellation of at least two symbols. A set of two or more virtual constellation points are define in a decision region corresponding to a possible value of the data word. The detected symbol estimate is processed to find a most likely virtual constellation point given the detected symbol estimate. The most likely value of the corresponding transmitted data word is determined based on the most likely virtual constellation point.

Abstract: A method and apparatus provide for stable signal demodulation in a communication system. The method and apparatus includes including detecting an erroneous demodulation value based on backward-demodulation of received signals, using a difference between a received signal to be demodulated and a preceding signal of the received signals and correcting the error demodulation value. Alternatively, backward-demodulation is used to confirm received signals.

Abstract: A method of two-way communications over a power distribution network in which outbound communication signals (O) and an inbound communication signals (I) modulate a time-varying waveform propagated through the network, on the low voltage side of the network. An outbound signal waveform is detected at a customer location (C) with remote communication equipment (RCE) at the customer location then producing a return or inbound communication signal. A corresponding inbound signal is produced in an associated voltage waveform and this signal is detected and processed by a distribution concentrator unit (DCU) at the sending end of the network. The transmission and detection of signals on the low voltage side of the network requires less energy than the generation, propagation, detection, and processing of signals on the high voltage side thereof.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: A dual-modem device opportunistically switches between spatial filtering techniques to enhance the received symbol estimates based at least in part on identifying, at a first modem, an interfering communication from a second modem. A WLAN modem can determine the timing of a WWAN transmission from a coexisting WWAN modem that interferes with a WLAN transmission and toggle between MRC and IRC receive techniques based at least in part on the determined timing.

Abstract: In an example, the present invention provides an analog to digital converter device for a high speed data transmission from 1 GS-s to 100 GS-s, although there can be other variations. In an example, the device has an input receiver device coupled to a transimpedance amplifier. In an example, the transimpedance amplifier is coupled to an input stream of data at 10 GHz to 100 GHz, or other variations.

Abstract: A circuit that introduces a calibrated amount of jitter and/or amplitude variation into a signal. By generating a signal with some predetermined amount of variation, signal consuming equipment may be tested to verify that it can properly extract the information from the signal, despite the presence of such variation. The circuit includes a signal propagation channel through which a signal may propagate. However, to introduce signal variation, the signal propagation channel passes close to electromagnetic interference generation circuitry. A calibration circuit has one or multiple settings that sets on or more values of parameters of the electromagnetic interference generation circuitry. During calibration, the parameters are adjusted until desired variation is detected, and which point the calibrated values are set and associated with that signal variation. This may be repeated for multiple calibration values and multiple settings. The ability to handle signals of different variances may then be accomplished.

Abstract: A system and method for characterizing a received radio frequency (RF) signal. In one embodiment, the system includes an antenna, a tuner, a sampler, a memory, and a processing unit connected to the memory, the processing unit being configured to receive a first sequence of samples from the sampler, perform a fast Fourier transform (FFT) operation, take the absolute value of a shifted complex frequency spectrum, perform a first filtering operation, perform a logarithmic operation, and perform an edge detection process to form an array of carrier centers and an array of carrier bandwidths. The processing unit is further configured to form, for each energy band identified as a result of the edge detection process, estimates of carrier characteristics and estimates of modulation characteristics.

Abstract: An apparatus includes at least one processor and a transceiver. The at least one processor is configured to execute computer readable instructions to: acquire first location information representing locations of a plurality of user terminals, second location information representing a location of at least one vehicle, and third location information representing a location of a destination of the plurality of user terminals; and determine a route from the location of the at least one vehicle to the location of the destination based on the first location information, the second location information and the third location information, wherein the route includes the location of each of the plurality of user terminals. The transceiver is configured to transmit the route to the plurality of user terminals.

Abstract: A signal detection apparatus includes a signal reception unit, an Analog to Digital (A/D) signal processing unit, and a user interface unit. The signal reception unit receives an external signal. The A/D signal processing unit determines whether the received signal is an abnormal signal based on a plurality of signal profiles having different signal characteristics, and obtains the abnormal signal if, as a result of the determination, it is determined that the received signal is the abnormal signal. The user interface unit displays the abnormal signal.

Abstract: An apparatus for controlling a feedback loop includes a digital finite impulse response filter configured to equalize digital samples to yield equalized data, a data detector circuit configured to detect values of the equalized data to yield detected data, a pattern detection circuit configured to detect at least one pattern in the detected data, an expected value comparison circuit configured to compare the digital samples corresponding to the at least one pattern with an expected value, and a feedback loop adaptation circuit configured to control a feedback loop based in part on whether the at least one pattern is detected by the pattern detection circuit and on an output of the expected value comparison circuit.

Abstract: A technique for spectral widening in a communication system may divide respective symbols of a block of symbols into symbol pieces of shorter duration than a symbol. The symbol pieces may be scrambled. The resulting scrambled symbol pieces may optionally be further spread using direct-sequence spreading prior to transmission. Error-control coding may also be used prior to dividing the symbols into symbol pieces and scrambling the symbol pieces. Additionally, the number of symbol pieces per symbol may be adjustable, based on channel characteristics, performance, or both.

Abstract: A method for operating a mobile device adapted for device-to-device (D2D) communications includes determining a utilization measure for discovery resources (DRs) allocated for D2D discovery in a communications system, and sending a utilization measure report to an evolved NodeB (eNB) when a reporting criterion is satisfied, wherein the utilization measure report is configured to prompt an adjustment to a number of DRs allocated for D2D discovery when an adjustment condition is met.

Abstract: A phase-locked loop (PLL) filter of a read channel includes a filter portion having an input coupled to delay circuitry having an output. The input of the filter portion is configured to receive a phase error signal. A look-up table is coupled to the filter portion. The look-up table comprises phase coefficients and frequency coefficients associated with a plurality of phase error magnitudes. The look-up table is configured to provide one or both of a selected phase coefficient and a selected frequency coefficient based on a magnitude of the phase error signal. The PLL filter is configured to adjust a bandwidth of the filter portion using one or both of the selected phase coefficient and the selected frequency coefficient. A phase signal indicative of estimated phase disturbance is produced at the output of the delay circuitry.

Abstract: A content based on location information is provided to a mobile terminal. The mobile terminal 10 communicatively connected to a location information related content providing server 200 performs a wireless communication or a short-range wireless communication, acquires a wireless ID of a counterpart terminal used for the wireless communication or the short-range wireless communication, and transmits the acquired wireless ID or location information acquired from the wireless ID to the location information related content providing server 200. The mobile terminal 10 receives a content associated with the transmitted location information or location information identified by the transmitted wireless ID from the location information related content providing server 200, and displays a link to the content as a panel on a screen.