Abstract: A communication system that uses keyed modulation to encode fixed frequency communications on a variable frequency power transmission signal in which a single communication bit is represented by a plurality of modulations. To provide a fixed communication rate, the number of modulations associated with each bit is dynamic varying as a function of the ratio of the communication frequency to the carrier signal frequency. In one embodiment, the present invention provides dynamic phase-shift-keyed modulation in which communications are generated by toggling a load at a rate that is a fraction of the power transfer frequency. In another embodiment, the present invention provides communication by toggling a load in the communication transmitter at a rate that is phase locked and at a harmonic of the power transfer frequency. In yet another embodiment, the present invention provides frequency-shift-keyed modulation, including, for example, modulation at one of two different frequencies.

Abstract: Systems and methods are disclosed for detection and mitigation of defects within a preamble portion of a signal, such as a data sector preamble recorded to a data storage medium. In certain embodiments, an apparatus may comprise a circuit configured to synchronize a sampling phase for sampling a signal pattern. The circuit may sample a preamble field of the signal pattern to obtain sample values, split the sample values into a plurality of groups, determine defect groups having samples corresponding to defects in the preamble field, remove the defect groups from the plurality of groups, and synchronize the sampling phase based on the plurality of groups.

Abstract: A quadrature detection unit subjects an FM signal to quadrature detection using a local oscillation signal and outputs a base band signal. A first correction unit and a second correction unit correct the base band signal using a DC offset correction value. A DC offset detection unit subjects the corrected base band signal to rectangular to polar conversion and derives the DC offset correction value such that amplitudes in a plurality of phase domains defined in an IQ plane approximate each other. An FM detection unit subjects the corrected base band signal to FM detection and generates a detection signal. An addition unit adds an offset to the detection signal. An AFC unit generates a control signal for controlling a frequency of a local oscillation signal based on the detection signal to which the offset is added.

Abstract: A first channel correlation is calculated for each pair of access terminals in a population of access terminals. A particular pair of access terminals is identified from the population of access terminals based on the first channel correlations. The population of access terminals includes a first access terminal of the particular pair of access terminals, a second access terminal of the particular pair of access terminals, and at least one remaining access terminal from the population of access terminals. A second channel correlation is calculated between the first access terminal and each of the at least one remaining access terminal. A third channel correlation is calculated between the second access terminal and each of the at least one remaining access terminal. One of the first access terminal and the second access terminal is selected to drop from service based on the second channel correlations and the third channel correlations.

Abstract: A method of spatially multiplexing data comprising a signal vector, the method comprising selecting first and second modulation schemes for the data transmission wherein the second modulation scheme is an interpolation in the plane of the first modulation scheme; and further wherein the modulation schemes are selected so as to maintain the same minimum Euclidean distance between vectors comprising the first and second modulation schemes as the minimum Euclidean distance within the first and second modulation schemes; and selecting a plurality of antennae, each of the plurality to concurrently transmit respective symbols of the signal vector.

Abstract: Systems and methods for biosignal acquisition, and in particular, electrocorticography signal acquisition, are disclosed for small area, low noise recording and digitization of brain signals from electrode arrays.

Abstract: Embodiments of the present invention provide a decoding method and apparatus. The method includes: receiving K user signals by using N subcarriers, where one user signal is carried on at least two subcarriers of the N subcarriers, one subcarrier carries at least two user signals of the K user signals, and 2?N<K; determining, from the N subcarriers, at least two target subcarriers that carry a target user signal, and performing initialization calculation on the target subcarriers, to obtain initialization calculation results; and determining, in a logarithm domain, a probability of each codeword in a codebook of the target user signal according to the initialization calculation results, to decode the target user signal. According to this method, decoding can be performed in the logarithm domain with low complexity.

Abstract: A system is connected to a single-wire communication line to perform bidirectional communication between a master side and a slave side, and an input clock-side transistor connected between a GND level and the communication line performs switching according to an input clock. A first transistor is connected between a first potential and the communication line, a second transistor has one end connected to a second potential, and a master-side resistor is connected between the other end of the second transistor and the other end of a third transistor. A fourth transistor is connected between the communication line and a third potential equal to or higher than the first potential, and a slave-side resistor is connected between the communication line and the GND level.

Abstract: There is provided a communication receiver comprising: an input for receiving a radio frequency, RF, input signal; and at least one finite impulse response, FIR, discrete time filter, DTF. The at least one FIR DTF comprises: an input circuit comprising an input port for sampling the RF input signal at a sampling frequency that is comparable to the input RF input signal; and N parallel branches, each branch having a set of input unit sampling capacitances, where each unit sampling capacitance is independently selectively coupleable to an output summing node. The input circuit is configured to convert an equivalent input impedance of the at least one FIR DTF around the sampling frequency to a real impedance.

Abstract: A method for processing a signal modulated with a variable carrier frequency includes calculating a coefficient for demodulation of the signal. The method also includes demodulating the signal by calculating discrete intermediate values utilizing the coefficient for a predefined maximum number of steps and calculating the signal with the aid of the intermediate values of the coefficient. The value of the coefficient is respectively calculated on the basis of carrier frequencies for each step.

Abstract: A transmitter in a Digital Subscriber Line (DSL) system includes a rate encoder configured to generate a first set of encoded bits using a set of least significant bits, a trellis shaper configured to generate a second set of encoded bits using a most significant bit and the first set of encoded bits, a first constellation mapper configured to generate a first point described by integer coordinates in a complex plane based on the first set of encoded bits obtained from the rate encoder, a second constellation mapper configured to generate a second point described by integer coordinates in the complex plane after interleaving two bits from the second set of encoded bits obtained from the trellis shaper, and a merger module configured to merge the first point with the second point to generate a symbol. The symbol represents a third point described by integer coordinates in the complex plane.

Abstract: Provided are a method and a device for transmitting interference cancellation information for cancelling interference between cells in a wireless communication system. The method for transmitting interference cancellation information may comprise the steps of: on the basis of feedback information received from a terminal belonging to a cell controlled by a predetermined base station, estimating a symbol error rate or a packet error rate on a cell boundary region; by comparing the symbol error rate or the packet error rate with a predetermined critical value, determining a probability indicator indicating the probability of cancelling interference between cells at the cell boundary region; and transmitting information on the probability indicator to an adjacent cell.

Abstract: Apparatuses and methods for power amplification and signal transmission using complex delta-sigma modulation are disclosed. In one embodiment, a complex delta sigma modulator unit comprising a complex polar quantizer within an integrator loop is disclosed. The complex polar quantizer quantizes the envelope of a complex integrated signal and produces a complex quantized output signal of substantially constant envelope. The complex quantized output signal is used in deriving a complex feedback signal within the integrator loop of the complex DSM. The complex quantized output signal may be used in driving a power amplifier substantially at saturation. In some embodiments, an adjacent channel power ratio (ACPR) enhancement technique is used to reduce the quantization noise in the complex quantized output signal.

Abstract: System and methods for generating and employing coherent multicarrier correlation can include receiving, from a transmitter, a plurality of radio frequency (RF) signals associated with a respective plurality of nominal carrier components. A processing circuitry can remove from each received RF signal the respective nominal carrier component to generate a corresponding baseband signal. The processing circuitry can generate, for each baseband signal, a respective correlation signal using the baseband signal and a reference signal. The processing circuitry can incorporate, to each correlation signal, the respective nominal carrier component of the RF signal associated with that correlation signal to generate a respective single-carrier correlation signal. The processing circuitry can aggregate the single-carrier correlation signals to generate a multi-carrier correlation signal.

Abstract: System and method of timing recovery for recovering a clock signal with reduced interference with clock phase correction by an adaptive equalizer. The equalizer in the timing recovery loop is dynamically adapted to the current channel characteristics that vary over time. The equalizer includes compensation logic operable to detect and compensate a correction of clock phase ascribed to the equalization adaptation. The compensation logic can calculate the offset between a center of filter (COF) value and a COF nominal value, the offset indicative of the amount and direction of clock phase correction contributed by the equalizer. Based on the offset, the compensation logic adjusts the equalized signal by adjusting the tap weights of the equalizer to correct the offset, thereby compensating the clock phase correction.

Abstract: A repeater circuit is disclosed. The repeater circuit is coupled to a transmission line driven by a first transmitter circuit and configured to detect a signal transition from a first voltage level to a second voltage level at a first position on the transmission line. The repeater circuit then reinforces the signal transition from the second voltage level to a third voltage level at the first position on the transmission line without interrupting a current through the transmission line.

Abstract: A method and apparatus for transmitting symbols for use in an FBMC wireless communication system are provided. The FBMC symbol transmission method includes determining a truncation point of a first FBMC symbol overlapping a transient transmission duration based on an energy distribution characteristic of a first filter applied to the first FBMC symbol, wherein the first FMBC symbol is to be transmitted in a non-transient transmission duration, truncating the first FBMC symbol at the truncation point in the transient transmission duration, changing an energy characteristic of a second filter, filtering the first FBMC symbol using the second filter, filtering FBMC symbols positioned within the non-transient transmission duration based on a non-transient transmission duration characteristic; and transmitting the filtered FBMC symbols at a corresponding transmission timing.

Abstract: Embodiments provide a signal transmission method and apparatus. The method includes: modulating, by using a phase-shift keying PSK scheme with rotation of a first angle, at least a part of pilot information carried in at least one signaling symbol in a signaling field of a data packet, to obtain modulated pilot information; and sending, to a receive end, a data packet that carries the modulated pilot information. A modulation scheme different from a conventional modulation scheme is used in the embodiments to modulate pilot information carried in a signaling symbol in a signaling field of a data packet, so that a data packet format corresponding to the modulation scheme can be effectively detected at a receive end.

Abstract: Presented are MIMO communications architectures among terminals with enhanced capability of frequency reuse by strategically placing active scattering platforms at right places. These architectures will not depend on multipaths passively from geometry of propagation channels and relative positions of transmitters and those of receivers. For advanced communications which demand high utility efficiency of frequency spectrum, multipath effects are purposely deployed through inexpensive active scattering objects between transmitters and receivers enable a same frequency slot be utilized many folds such as 10×, 100× or even more. These active scatters are to generate favorable geometries of multiple paths for frequency reuse through MIMO techniques. These scatters may be man-made active repeaters, which can be implemented as small as 5 to 10 watt lightbulbs for indoor mobile communications such as in large indoor shopping malls.

Abstract: A digital pre-distortion system can inversely model a power amplifier of a system to linearize the transmitter. A complex baseband model for digital pre-distortion based on a narrowband signal assumption is unworkable for an ultra wide band Cable television application. Predistortion can use a true wide band model including real-valued basis terms, obtained from a real-valued signal. When raised to a power, both even and odd harmonics or both odd or even other non-linear terms are represented and negative frequency fold-over can be accounted for. A Hilbert transform can be applied. Compressed sensing can be used to reduce the number of basis terms in the true real wide band model to generate a sparse model. Sparse equalization can be added to improve the stability of the digital pre-distortion system.