Abstract: An apparatus having a circuit is disclosed. The circuit may be configured to (i) receive an input signal from a communication channel and (ii) generate an intermediate signal by amplifying the input signal (a) by a low-frequency gain in response to an amplitude control signal and (b) by a high-frequency gain in response to a boost control signal.

Abstract: Receiver circuits in serial lanes each generate a synchronous clock signal that is aligned with a master clock signal to allow synchronous transfer of data onto the master clock domain without corruption. A serial-to-parallel converter circuit in each receiver circuit converts a serial data signal into parallel data signals in response to one of the synchronous clock signals. Phase detection circuitry generates an indication of a phase shift based on a phase offset between the synchronous and master clock signals. A clock signal generation circuit provides an adjustment to a phase of the synchronous clock signal based on the indication of the phase shift. The serial-to-parallel converter circuit adjusts positions of bits indicated by the parallel data signals based on the adjustment to the phase of the synchronous clock signal.

Abstract: A method of operation of a communication system includes: determining a channel estimate based on an arriving communication for characterizing a channel; calculating a conditional measure based on the channel estimate for characterizing the channel at a subsequent index; generating a channel-based probability function using the conditional measure, the channel-based probability function based on a feedback metric; determining a stochastic channel indicator based on a value of the feedback metric producing a target condition from the channel-based probability function; and sending the stochastic channel indicator for controlling communication at a base station for communication through a device.

Abstract: A circuit and a method for removing a frequency offset and a communication apparatus including the circuit, capable of removing the frequency offset by tracking rapidly and accurately in a payload section. A sequence of sample levels is obtained by sampling a frequency level of the baseband signal at every 0.5 symbol interval. Absolute values of differences between the frequency levels adjacent to each other at every 1 symbol are calculated as first difference absolute values. Absolute values of differences between the frequency levels adjacent to each other at every 1 symbol are calculated as second difference absolute values. When the first difference absolute values are greater than a predetermined first determination value or the second difference absolute values are less than a predetermined second determination value, the average value calculated is set as the frequency offset.

Abstract: The invention is directed to a novel computer implemented method for finding a modulation format that has better receiver sensitivity than modulation formats that are currently being used, with a correlated symbol modulation in which neighboring symbols are coded and decoded together to increase receiver sensitivity.

Abstract: A method of blind tap coefficient adaptation includes receiving a digital data signal including random digital data, equalizing a first portion of the digital data signal using a first set of predetermined tap coefficients and a second portion of the digital data signal using a second set of predetermined tap coefficients. The method includes generating a first eye diagram and a second eye diagram from a first portion and a second portion of an equalized signal, respectively. The first eye diagram is compared with the second eye diagram to determine which of the sets of predetermined tap coefficients results in a data signal having a higher signal quality. The method includes inputting to an equalizer as an initial set of tap coefficients the first set of predetermined tap coefficients or the second set of predetermined tap coefficients according to the determination.

Abstract: Provided is a frequency sensing method and apparatus in an orthogonal frequency division multiplexing (OFDM) system. Provided is a method of sensing a frequency of a received signal that is received from an outside in order to perform one of a plurality of radio communications. An OFDM apparatus may need to inspect a required frequency band before or after performing one of the plurality of radio communications, and to determine whether the frequency band is being used by another radio communication.

Abstract: The present invention provides a method of transmitting broadcast signals. The method includes, formatting input streams into Data Pipe, DP, data; Low-Density Parity-Check, LDPC, encoding the DP data according to a code rate; bit interleaving the LDPC encoded DP data; mapping the bit interleaved DP data onto constellations according to one of QAM (Quadrature Amplitude Modulation), NUQ (Non-Uniform QAM) or NUC (Non-Uniform Constellation); Multi-Input Multi-Output, MIMO, encoding the mapped DP data by using a MIMO encoding matrix having a MIMO encoding parameter; building at least one signal frame by mapping the MIMO encoded DP data; and modulating data in the built signal frame by an Orthogonal Frequency Division Multiplexing, OFDM, method and transmitting the broadcast signals having the modulated data.

Abstract: The present invention relates to a transmission interface device capable of calibrating the transmission frequency automatically, which comprises a clock generating unit, a data transmission unit, and a control unit. The clock generating unit is used for generating an operating clock, which determines a transmission frequency. The data transmission unit is used for connecting to a host and transmitting a plurality of data to the host or receiving the plurality of data from the host according to the operating clock. When the host or the data transmission unit detects transmission errors in the plurality of data, the host or the data transmission unit generates an error handling. The control unit generates an adjusting signal according to the error handling and transmits the adjusting signal to the clock generating unit for adjusting the transmission frequency of the operating clock.

Abstract: The invention concerns a circuit for multi-standard wireless RF transmission comprising: input circuitry (302 to 314) for generating a transmission signal (IT(t), QT(t)) based on an input data signal (I, Q); a power amplifier (316) adapted to amplify said transmission signal to provide an output signal (S(t)) for transmission via at least one antenna; and feedback circuitry (320 to 340) comprising at least one variable low-pass filter (334, 336) for generating a feedback signal (IFB, QFB) based on said output signal, wherein said input circuitry further comprises pre-distortion circuitry (302) adapted to modify said input data signal (I, Q) based on said feedback signal.

Abstract: A wireless transmitter includes an RF signal generation circuit, a driver amplifier, and a class-D amplifier. The RF signal generation circuit detects an amplitude signal and a phase signal based on a digital baseband signal subjected to orthogonal modulation, thus generating a pulse phase signal which is High in response to the phase ranging from 0° to 180° but is Low in response to the phase ranging from 180° to 360°. The amplitude signal is subjected to sigma-delta modulation in synchronism with the pulse phase signal and further mixed with the pulse phase signal, thus producing an RF pulse signal. The RF pulse signal is input to the class-D amplifier via the driver amplifier, thus outputting a pulse voltage signal based on a reference voltage. Thus, it is possible to achieve a small-size wireless transmitter with good noise/distortion characteristics and high power efficiency.

Abstract: A method for transmitting data includes mapping a first coded information bit stream intended for a first transmit antenna onto at least one first spreading sequence of a plurality of first spreading sequences to generate a first data stream, mapping a second coded information bit stream intended for a second transmit antenna onto at least one second spreading sequence of a plurality of second spreading sequences to generate a second data stream. The method also includes transmitting the first data stream and the second data stream on respective transmit antennas.

Abstract: Techniques are presented herein for distinguishing between the DC component of a real signal and DC energy of a received signal due to the radio receiver circuitry. Samples are obtained of a received signal derived from output of a receiver of a communication device. A mean of the samples is computed over a sample window comprising a predetermined number of samples. First and second thresholds are provided, the first threshold being greater than the second threshold. An absolute value of the mean is compared with respect to the first threshold and the second threshold as samples are obtained in the sample window. A selection is made between the first threshold and the second threshold for purposes of comparison with the absolute value of the mean to determine whether energy at DC is a true/real DC component of the received signal or is due to circuitry of the receiver.

Abstract: The present disclosure is directed at a method and apparatus for generating a metric for use in any one or more of lock detection, SNR estimation, and modulation classification. To generate the metric, an input angle in the form of a symbol phase or a difference in symbol phases is used to evaluate a base function. The base function relates possible metrics to possible input angles using a triangle wave having its maxima or minima at ideal input angles, and the other of its maxima or minima at angles midway the ideal input angles. Described are embodiments that are one or more of non-data aided; that may be implemented relatively efficiently in hardware; that can function using one sample/symbol; that can achieve relatively good detection certainty using relatively few estimates; and that can be used to implement modulation classifiers, lock detectors, and SNR estimators that are resilient to imperfections in automatic gain control.

Abstract: Described are a method for generating a metric that is a function of a phase difference between a modulated carrier and a local carrier, and a phase detector for performing such a method. A baseband symbol is obtained from the modulated carrier, and the phase of the symbol is determined. Assuming that the modulation used to modulate the modulated carrier has a constellation diagram with M-fold rotational symmetry, the metric can be generated from the phase by evaluating a base function that includes a triangle wave having positively and negatively sloped linear segments whose slopes have identical absolute values and that is periodic with a period of 2?/M radians. Alternatively or additionally, if the ideal symbol phases are uniformly distributed, the metric can be generated by evaluating a version of the base function in which the ideal symbol phases correspond to identically valued metrics located on the triangle wave.

Abstract: In a method for generating a PHY data unit for transmission via a communication channel, a modulation scheme is selected from a plurality of modulation schemes, information bits are encoded to generate encoded data using one or more encoders, and an interleaving parameter NCOL is selected using the selected modulation scheme. NCOL varies for different modulation schemes. The encoded data is interleaved, which includes entering the encoded data into NROW rows and reading the encoded data out in NCOL columns. The payload information of the PHY data unit is modulated according to the modulation scheme, and a plurality of OFDM symbols is formed based on the modulated payload information.

Abstract: Passive detection of a quadrature amplitude modulated (QAM) signal amid noise is achieved by detection of a spectral component of a detected signal that corresponds to a known QAM symbol rate in, for example, a QAM modulated broadband communication system (BCS). Improved authentication can be provided by simultaneously detecting symbol rate components in two or more QAM bands. No modification of a broadband communication system such as by including a marker signal is required and thus there is no requirement for dedication of a portion of the broadband communication system spectrum or problem of marker signal interference with BCS signals.

Abstract: A frequency offset estimation method for a multi-carrier communication system is provided. The method includes: transforming a representation of a reception signal from a time domain to a frequency domain, and generating a plurality of symbols; calculating a correlation of two symbols among the symbols, and obtaining a plurality of correlating complex numbers corresponding to a plurality of subcarriers; generating M number of candidate subcarrier position sets according to a subcarrier position set of a specific signal and M number of candidate frequency offsets; calculating M number of calculated values according to the correlating complex numbers corresponding to the M number of candidate subcarrier position sets; and determining a frequency offset according to the maximum calculated value among the M number of calculated values.

Abstract: A method of calibrating data slicer-latches in a receiver to remove offset errors in the slicer-latches. A known voltage is applied to all but one of the inputs of the slicer-latch. The remaining input receives an offset cancelation voltage from a DAC is stepped upward from a minimum voltage until the slicer-latch output transitions by incrementing a codeword to the DAC and the codeword that resulted the transition is saved. Then the offset cancelation voltage is swept downward in steps from a maximum voltage until the slicer-latch output transitions and the codeword that caused the transition is averaged with the stored codeword. The average of the codewords is applied to the DAC to generate the offset cancelation voltage used during normal operation of the receiver.

Abstract: Disclosed herein are a passive equalizer and a high-speed digital signal transmission system, including first and second impedances connected in series to a first transfer line, third and fourth impedances connected in series to a second transfer line, a first inductor connected in parallel between the first impedance and the second impedance, a second inductor connected in parallel between the third impedance and the fourth impedance, and a resistor connected in series between the first inductor and the second inductor.