Abstract: Briefly, a wireless communication system having two or more wireless communication devices. The wireless communication device includes a transmitter to transmit a signal over a wireless channel and to determine a bandwidth of the wireless channel and a power level of the signal based on a quality value of the wireless channel. A method of varying the bandwidth of the wireless channel is also provided.

Abstract: Over a channel, a signal including a desired portion associated with a desired channel and an undesired portion mixed with said desired portion may be received. Based on prior knowledge and/or empirical estimation of the desired channel and an empirical estimate of the signal cross-covariance, the desired portion from the received signal may be recovered by adaptively equalizing the channel. In one embodiment, a receiver, such as a mobile device (e.g., a cellular phone) includes a processor operably coupled to a communication interface including at least two antennas to receive the signal. The receiver may further include a MODEM that may be operably coupled to the processor, that includes an adaptive equalizer capable of detecting the signal in the presence of co-channel interference from several independent sources, inter-symbol interference and fading, for recovering the desired portion in a cellular environment with time division multiple access (TDMA) to enable digital transmission of the signal.

Abstract: A receiver includes a searcher to identify pilot signals within a received signal and a pilot tracking unit to continuously track pilot signals identified by the searcher. The pilot signals tracked by the pilot tracking unit may include pilot signals associated with an affiliated base station as well as pilot signals associated with non-affiliated base stations. In at least one embodiment, the pilot tracking unit continuously tracks most or all of the pilot signals identified by the searcher.

Abstract: Briefly, a wireless communication device having a receiver includes a pilot signal interference canceller and a linear interference suppressor is provided. The pilot signal interference canceller and the linear interference suppressor jointly operate to cancel a pilot signal interference and other interference which are part of a received signal. A method for jointly cancel the interference by the pilot signal interference canceller and the linear interference suppressor is also provided.

Abstract: Interference reduction is achieved within a communication device using a low complexity antenna array. In at least one embodiment, phase and magnitude values associated with an antenna element within a low complexity array are dynamically adjusted during device operation in a manner that enhances a predetermined quality criterion (e.g., SINR).

Abstract: A receiver includes a searcher to identify pilot signals within a received signal and a pilot tracking unit to continuously track pilot signals identified by the searcher. The pilot signals tracked by the pilot tracking unit may include pilot signals associated with an affiliated base station as well as pilot signals associated with non-affiliated base stations. In at least one embodiment, the pilot tracking unit continuously tracks most or all of the pilot signals identified by the searcher.

Abstract: A multi-user detector for use in a CDMA receiver system includes a channel tap interpolator to generate interpolated channel taps for users of interest. The interpolated channel taps occur at integer multiples of a chip period from a sampling reference point. The channel tap interpolation allows detection processing to proceed in the chip domain, rather than in the sample domain, thus reducing the complexity of the multi-user solution significantly. In at least one approach, a number of low dimensionality “virtual” users are defined based on the recursive property of the spreading sequences. Solutions may then be developed for the virtual users using conventional detection (e.g., MMSE) techniques.

Abstract: Interference reduction is achieved within a communication device using a low complexity antenna array. In at least one embodiment, phase and magnitude values associated with an antenna element within a low complexity array are dynamically adjusted during device operation in a manner that enhances a predetermined quality criterion such as signal to interference and noise ratio (SINR).

Abstract: A communication device including a per finger interference reducer adapted to remove an interference effect of at least one pilot signal from the output of a despreader of the finger.

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: In an embodiment, a transmitter section for a mobile device includes a predistorter for predistorting an input signal input to a modulation section. Predistortion values may be selected from a look-up table in response to a fed back signal from the output of the modulation section. A delay between the input signal and the fed back signal may be determined in two stages: a coarse delay estimation for determining a whole number of sample cycles, and a fine delay estimation for determining a fraction of a sample cycle to be added to the coarse delay estimation value.

Abstract: Estimates of interference from co-channel pilot signals from one or more base stations may be formed at a receiver and subtracted out from the received signal to improve the detection of a desired signal. The complexity of pilot interference cancellation may be reduced by selecting only particular crosscorrelation terms to be estimated and processed. The remaining terms or crosscorrelation values may be eliminated from the computation, reducing computational complexity. In addition, selection decisions may be stored to reduce the need to excessively reevaluate the selection decision.

Abstract: A wave digital filter which includes a plurality of memoryless adapters each having two or more ports, each port including an input and an output, and at least one controlled gate which delays the propagation of a value into at least one input of at least one of the adapters.

Abstract: Linear transformations are carried out on a matrix that represents information such as an image or a communication. In an aspect, the matrix is processed to remove duplicate information. The duplicate information can be duplicate rows, or zero rows. This matrix is then transformed into a modified matrix, indicating duplicate information is removed to produce a modified matrix.

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: A method of assigning values to parameters for IQ mismatch cancellation. The method includes providing values to a processing path of a communication device, passing the provided values through an IQ modulator, at least one non-linear element and an IQ demodulator, to produce distorted values, and estimating at least one parameter for cancellation of IQ mismatch effects of the communication device responsive to the provided values and to the distorted values.

Abstract: Linear transformations are carried out on a matrix that represents information such as an image or a communication. In an aspect, the matrix is processed to remove duplicate information. The duplicate information can be duplicate rows, or zero rows. This matrix is then transformed into a modifed matrix, indicating duplicate information is removed to produce a modified matrix.

Abstract: A receiver including a signal reception unit, for receiving a signal from a dynamically fading channel, a demodulator, connected to the signal reception unit, for demodulating the received signal, thereby producing a demodulated signal therefrom, a quantizing processor, connected to the demodulator and to the signal reception unit, for analyzing the received signal and for quantizing the demodulated signal, thereby producing a quantized signal, and a decoder, connected to the quantizing processor, for decoding the quantized signal, wherein the quantizing processor normalizes the demodulated signal according to the estimated fading of the received signal.

Abstract: A unified minimum mean square error (MMSE) equalization/multi-user detection (MUD) approach for demodulating direct sequence CDMA (DS-CDMA) signals is described. In at least one embodiment, the unified approach is capable of generating a variety of cost-effective receiver demodulation techniques that may range from, for example, a low cost linear MMSE equalization technique to a relatively high complexity MMSE MUD.

Abstract: A method of iteratively decoding a block of information based on a predetermined error detection structure is provided, The method includes: a) performing a sequence of iterations for decoding the block of information to produce a decoded output in each iteration; b) producing from the decoded output, and the predetermined error detection structure, a reliability metric for the respective iteration, which reliability metric is based on said predetermined error detection structure; and c) utilizing the reliability metric as a criterion in an abort decision with respect to further iterations of decoding the respective block of information