Abstract: According to one embodiment, an ASK signal generator includes a differential oscillator, a first modulator, a second modulator, a first transmission line, a second transmission line and an impedance adjustment circuit. The differential oscillator generates first and second signals having an opposite phase, and outputs the first and second signals from first and second output terminals. The first modulator connected to the first output terminal is set in the normally off state. The second modulator connected to the second output terminal is turned on or off according to a digital signal. The first and second transmission lines connected to the first and second output terminals have a length equal to a ¼ wavelength of the oscillation frequency of the differential oscillator. The impedance adjustment circuit is operated together with the second modulator according to the digital signal.

Abstract: Transmission channel estimation is performed for NT×NR reception signals and estimated transmission channel values are thereby output. The estimated transmission channel values are divided into N groups of NT×M estimated transmission channel values and a covariance matrix with M rows and N columns is obtained for each of the estimated transmission channel value groups. The N covariance matrixes are averaged over a predetermined range in terms of at least a time or a frequency (first averaging). Eigenvectors are generated based on respective N averaging outputs. Transmission channels between base station antennas and terminal antennas are generated from the eigenvectors and the estimated transmission channel values. Covariance matrixes are obtained for the generated transmission channels. The covariance matrixes are averaged over a different range from the range used in the first averaging (second averaging) and a beam forming weight is obtained by combining the generated eigenvectors.

Abstract: A method of operation of a wireless communication system includes: tuning a receiver front end for receiving a radio-frequency signal; correcting, with an in-phase/quadrature (I/Q) compensation module, an I/Q imbalance from the receiver front end including estimating by a linear minimum mean-square error (LMMSE) module; and processing by a base band receiver for digitizing an output of the I/Q compensation module for generating a receiver data.

Abstract: Communication systems may benefit from an HSPA MIMO receiver configured for receipt of an imbalanced transmit signal, as well as a method for operating the receiver. According to certain embodiments, a method can include receiving a multiple-input multiple-output system communication signal comprising at least one primary signal at a first power level from a first antenna and a secondary signal at a second power level different from the first power level from a second antenna. The method can also include estimating at least one parameter of the communication signal. The method can further include applying the at least one parameter as estimated to calculate linear minimum mean square error coefficients. The method can additionally include applying the linear minimum mean square error coefficients to process the communication signal.

Abstract: Provided is a method and a device for generating a precoding matrix in a wireless communication system. The method for generating the precoding matrix comprises a step of receiving from a terminal feedback including information on the error angle ? of channel direction information (CDI), which indicates the direction of a channel direction vector, and a step of generating the precoding matrix based on the information on the error angle ? of the CDI, wherein the error angle ? of the CDI indicates the angle between the channel direction vector and a quantized channel direction vector, and includes at least one of a channel quantization error component, a channel feedback delay error component, and a channel estimation error component.

Abstract: The present invention, pertaining to the field of mobile broadcast television technologies, discloses a method and apparatus for generating a broadcast positioning signal, and a positioning method. According to the present invention, a broadcast positioning signal is generated by inserting a spread spectrum signal and a first spread spectrum signal in an orthogonal frequency-division multiplexing (OFDM) signal, and a receiver is positioned according to broadcast positioning signals from at least three different senders.

Abstract: Tools capable of improving the accuracy of decision feedback equalization (DFE) are described. The tools may adapt a DFE using a more-equal distribution of signals than those actually received. The tools may do so by disregarding, averaging, or weighting certain signals when adapting the DFE when those signals represent an unequal distribution of bit patterns. In one example, the tools detect and disregard some of the signals representing idle bit patterns that are received more often than other bit patterns. The tools may also or instead compensate for a bit pattern that is never or rarely received.

Abstract: A scheme determines the first significant path (FSP) of a received multipath signal, from data defining the relative delay and the amplitude of the individual signal paths occurring in a series of time frames. The scheme includes filtering the data to spread the signal paths, performing a persistence test between frames to reject spurious signal paths, combining the energy of the signal paths in a frame, applying a test to determine the time at which the combined energy satisfies a criterion, and selecting the FSP dependent on that time. The combined energy may be evaluated within a sliding window, and the position of the window within the frame determined that maximizes the combined energy. Alternatively, the combined energy may be evaluated as the cumulative energy through the frame, and the position determined at which the cumulative energy reaches a threshold.

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: A receiver for a multi-channel communication system can include a down-converter device, an analog-to-digital converter (ADC), and a plurality of digital channel selection devices. The down-converter device can be configured to down-convert a plurality of analog signals from the multi-channel communication system to a plurality of corresponding low intermediate frequency (IF) signals. The ADC can be configured to convert the plurality of corresponding low-IF signals to a plurality of digital signals. Further, each digital channel selection device from the plurality of digital channel selection devices can be configured to select a digital signal corresponding to a channel of interest from the plurality of digital signals for further processing.

Abstract: Multiple-input multiple-output (MIMO) wireless communication techniques are provided that involve mapping multiple spatial streams to corresponding modes of a wireless channel between a plurality of antennas of a first wireless communication device and a plurality of antennas of a second wireless communication device so as to allocate or distribute power unequally to the plurality of modes. In addition, techniques are provided herein to cyclically shift a mapping of spatial streams to modes of the channel.

Abstract: A method significantly reduces the average power for radio communication in a communication system, such as a system that has applications requiring low communication latency. The method may use a low power radio communication circuit (e.g., a non-heterodyne receiver) to wait for a communication request, taking advantage of the low power consumption of the radio communication circuit. Subsequent to receiving and validating the communication request, the communication system may switch to a more efficient—but higher power—communication circuit. Thus, effective communication is achieved without making undesirable tradeoffs, such as reduced sensitivity.

Abstract: A method of wireless communication with improved performance employs an equalizer receiver with multiple receive antennas. Equalizer taps for linear filters of the equalizer receiver are generated by determining a conditioned covariance matrix of a first data path and a second data path based on a first gain (g0) of this first data path and a second gain (g1) of the second data path. The equalizer taps of the first data path and the second data path are determined based on the conditioned covariance matrix. The first data path and the second data path are then equalized using the equalizer taps. An equalized signal is generated by combining the equalized first data path with the equalized second data path.

Abstract: Systems and methods for simultaneously communicating over multiple air interfaces using a single transceiver are described herein. An input is received at a transceiver. The input has a first signal encoded using a first radio technology and a second signal encoded using a second radio technology. The input is converted from an analog domain to a digital domain. The input is separated into the first signal and the second signal in the digital domain.

Abstract: A mixed waveform configuration for wireless communications including a first portion that is modulated according to a single-carrier modulation scheme and a second portion that is modulated according to a multi-carrier modulation scheme. The waveform is specified so that a channel impulse response (CIR) estimate obtainable from the first portion is reusable for acquisition of the second portion. The first portion includes a preamble and header and the second portion typically incorporates the payload.

Abstract: Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal over the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a baseband signal after a first mapping and a baseband signal after a second mapping by a precoding weight and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.

Abstract: A received signal of interest is processed by determining timing of interference spikes in the received signal of interest. Receivers can determine when certain types of interference spikes are expected to occur, e.g., based on when different users are scheduled to transmit data during an overlapping portion of the same transmission time interval. The interference timing information is used by the receiver to soft scale signal values recovered from the received signal of interest that coincide with the interference spikes separately from remaining ones of the signal values. This way, fast changing interference power can be accurately tracked during periods of known interference spikes while also accurately tracking slower changing interference power during other periods.

Abstract: A method for compensating for gain changes of an N-level pulse amplitude modulation (PAM-N) modulated signal. The method comprises comparing the PAM-N modulated signal to N?1 configurable thresholds, wherein the input PAM-N modulated signal is also equalized and the N?1 configurable thresholds are N?1 different voltage levels; tracking gain changes in the input PAM-N modulated signal by comparing the input PAM-N modulated signal to a compensation threshold; and adjusting a level of the at least one of the N?1 configurable thresholds of the N?1 comparators based on an output of the compensation comparator, thereby offsetting a crossing point of the at least one comparator respective of the at least one of the N?1 configurable thresholds to compensate for gain changes in the input PAM-N modulated signal.

Abstract: A diversity reception device includes branches, a controller and a combining section. Each branch includes a correlation section that generates a correlation signal that represents a correlation between a received signal and a delayed signal or between the received signal and a reference signal, where the correlation signal level disregarding the received signal level, a time position detector that detects time positions at which the level of the correlation signal is at a peak, a demodulation section that demodulates the received signal, and a multiplication section that multiplies the demodulated signal with a weighting factor. The controller controls the weighting factor on the basis of the respective levels of the correlation signals at the detected time positions. The combining section combines, by adding, the respective demodulated signals of the branches subsequent to the demodulated signal of each branch being multiplied with the weighting factor.

Abstract: Network coding may be performed with encoding and/or decoding that involves a multiplication operation. A communication node is adapted to perform multiplicative network coding. The communication node includes an encoder and a decoder. The encoder is arranged to perform an encoding operation by multiplying two or more signals that bear information to form a composite signal. The decoder is arranged to perform a decoding operation by multiplying a received composite signal with one or more complex-conjugated signals, with the decoder yielding a decoded signal that bears information. With the encoding operation, the communication node is adapted to at least partially perform multiplicative-network-coding encoding for a sending communication mode. With the decoding operation, the communication node is adapted to at least partially perform multiplicative-network-coding decoding for a receiving communication mode.