Abstract: A user equipment device operating in a cellular communications system includes a neighbor cell searcher configured to receive a first reference signal transmitted from a base station of a first cell of the cellular communications system and determine first channel information associated with the first cell, and receive a second reference signal transmitted from a base station of a second cell of the cellular communications system and determine second channel information associated with the second cell. A channel estimator is configured to generate correlations between times and frequencies associated with reception of the first reference signal and the second reference signal, and generate a channel estimate corresponding to the first reference signal based on the first channel information, the second channel information, and the correlations.

Abstract: A method includes accepting input values u and v, respectively identifying a uth root Zadoff-Chu sequence whose length is a prime number, and a vth cyclic shift for the sequence. Elements of a Discrete Fourier Transform (DFT) of the vth cyclic shift of the uth root Zadoff-Chu sequence are computed using processing circuitry, by evaluating a single respective exponent depending on u and v in computing each of the elements.

Abstract: A method includes holding in a memory of a communication terminal multiple predefined vectors, each including signal autocorrelation values computed for a respective Doppler shift. A signal is received, and empirical autocorrelation values are calculated for the received signal. An actual Doppler shift of the received signal is estimated by selecting, from among the predefined vectors, a vector whose autocorrelation values best match the empirical autocorrelation values of the received signal.

Abstract: A method includes receiving signals transmitted over a communication channel in multiple blocks transmitted in respective frequency bins during respective time intervals. An estimate of the communication channel, for a given block transmitted during a respective time interval, is computed by (i) computing respective interim filtering results for the blocks transmitted in the respective time interval in the respective frequency bins belonging to the predefined subset, by filtering a first group of the reference signals that are transmitted in odd-order frequency bins and in a first set of symbols, so as to produce odd-order interim filtering results, and filtering a second group of the reference signals that are transmitted in even-order frequency bins and in a second set of symbols that does not overlap the first set, so as to produce even-order interim filtering results; and (ii) combining the odd-order interim filtering results and the even-order interim filtering results.

Abstract: A method includes holding in a memory of a communication terminal multiple predefined vectors, each including signal autocorrelation values computed for a respective Doppler shift. A signal is received, and empirical autocorrelation values are calculated for the received signal. An actual Doppler shift of the received signal is estimated by selecting, from among the predefined vectors, a vector whose autocorrelation values best match the empirical autocorrelation values of the received signal.

Abstract: Briefly, a method and apparatus to calculate cross-correlation values of complex binary sequences are provided. The apparatus may include a transformation unit and a cross-correlator. The cross-correlator may include a cross-correlation controller to provide, based on a type bit and a sign bit, a real component and/or an imaginary component of signals of complex binary sequences to a real accumulator and/or to an imaginary accumulator.

Abstract: Briefly, a method and apparatus to calculate cross-correlation values of complex binary sequences are provided. The apparatus may include a transformation unit and a cross-correlator. The cross-correlator may include a cross-correlation controller to provide, based on a type bit and a sign bit, a real component and/or an imaginary component of signals of complex binary sequences to a real accumulator and/or to an imaginary accumulator.

Abstract: A method includes receiving signals that are transmitted over a communication channel in multiple blocks that are transmitted in respective frequency bins during respective time intervals, some of the blocks in a predefined subset of the frequency bins containing reference signals. An estimate of the communication channel, for a given block transmitted during a respective time interval, is computed by (i) computing respective interim filtering results for the blocks transmitted in the respective time interval in the respective frequency bins belonging to the predefined subset, by filtering one or more of the reference signals transmitted in the respective frequency bins of the block; and (ii) combining the interim filtering results to produce the estimate of the communication channel.

Abstract: A method includes accepting input values u and v, respectively identifying a uth root Zadoff-Chu sequence whose length is a prime number, and a vth cyclic shift for the sequence. Elements of a Discrete Fourier Transform (DFT) of the vth cyclic shift of the uth root Zadoff-Chu sequence are computed using processing circuitry, by evaluating a single respective exponent depending on u and v in computing each of the elements.

Abstract: A method in a receiver includes receiving from a transmitter an aggregated-spectrum signal including at least first and second component carriers in respective spectral bands. Information related to processing one or more of the component carriers is buffered in at least one shared buffer, such that storage locations in the shared buffer are selectably assignable for storing at least first information related to the processing of the first component carrier and second information related to the processing of the second component carrier. The one or more of the component carriers are processed in the receiver using the information buffered in the shared buffer.

Abstract: A method includes accepting input values u and v, respectively identifying a uth root Zadoff-Chu sequence whose length is a prime number, and a vth cyclic shift for the sequence. Elements of a Discrete Fourier Transform (DFT) of the vth cyclic shift of the uth root Zadoff-Chu sequence are computed using processing circuitry, by evaluating a single respective exponent depending on u and v in computing each of the elements.

Abstract: A method for a user equipment device includes receiving a reference signal from a desired transmitter and obtaining information about other, interfering transmitters whose signals are receivable by the user equipment. The information includes a reference signal sequence of reference signals transmitted by the other transmitters. The method also includes modeling interference caused by the reference signals of the other transmitters on the received reference signal when determining a channel estimate for a channel between the user equipment device and the desired transmitter.

Abstract: Briefly, a method and apparatus to calculate cross-correlation values of complex binary sequences are provided. The apparatus may include a transformation unit and a cross-correlator. The cross-correlator may include a cross-correlation controller to provide, based on a type bit and a sign bit, a real component and/or an imaginary component of signals of complex binary sequences to a real accumulator and/or to an imaginary accumulator.

Abstract: A method in a receiver includes receiving from a transmitter an aggregated-spectrum signal including at least first and second component carriers in respective spectral bands. Information related to processing one or more of the component carriers is buffered in at least one shared buffer, such that storage locations in the shared buffer are selectably assignable for storing at least first information related to the processing of the first component carrier and second information related to the processing of the second component carrier. The one or more of the component carriers are processed in the receiver using the information buffered in the shared buffer.

Abstract: A method includes accepting input values u and v, respectively identifying a uth root Zadoff-Chu sequence whose length is a prime number, and a vth cyclic shift for the sequence. Elements of a Discrete Fourier Transform (DFT) of the vth cyclic shift of the uth root Zadoff-Chu sequence are computed using processing circuitry, by evaluating a single respective exponent depending on u and v in computing each of the elements.

Abstract: In some exemplary embodiments of the invention, a transfer function of a filter for a fractional-N sigma-delta modulator may be calculated to be optimized according to predefined optimization criteria. For example, the optimization criteria may include spectral cleanliness at the output of the modulator, or the mean squared error of the input to the filter and the input to a voltage controlled oscillator of the fractional-N phase locked loop (PLL). In some exemplary embodiments, the filter may be adjusted to compensate for variations and/or impairments in the analog fractional-N PLL. A non-exhaustive list of examples for the transfer function includes a finite impulse response and an infinite impulse response.

Abstract: Briefly, according to some embodiments of the invention a method and apparatus to generate a filter are provided. The apparatus may include a phase modulation unit to vary a phase component of a signal, a measurement unit to measure a parameter of the phase modulation unit and a filter generator to generate a filter based on the parameter. In some embodiments of the invention, the filter is adapted to provide a compensated signal to the phase modulation unit to compensate for deviation of the parameter.

Abstract: Briefly, a method and apparatus to calculate cross-correlation values of complex binary sequences are provided. The apparatus may include a transformation unit and a cross-correlator. The cross-correlator may include a cross-correlation controller to provide, based on a type bit and a sign bit, a real component and/or an imaginary component of signals of complex binary sequences to a real accumulator and/or to an imaginary accumulator.

Abstract: A receiver in a wireless communication system utilizes a metric to minimize the error probability in transmitted information. The receiver may use a detector utilizing multiuser detection or rake detection. The output symbols of the detector are examined and a metric is obtained related to the noise and interference that may have distorted the transmission of the symbol. This metric is supplied to a channel decoder along with the symbol to improve decoding.

Abstract: A system to decode a multirate CDMA signal. In one aspect the system includes a high rate detector to generate high rate outputs based upon decoding an input signal that includes high rate users and low rate users. The high rate outputs include actual high rate users and effective high rate users. A second stage applies a first linear transformation to the high rate outputs to generate second stage outputs. A third stage applies a second linear transformation to the second stage outputs to generate decoupled low rate user outputs and decoupled actual high rate user outputs.