Asynchronous sampling digital detection (ASDD) methods and apparatus are described. In one embodiment, noise-corrupted information is received and comprises a plurality of information-carrying events which encode binary information which is desired to be retrieved. A plurality of values are extracted from the noise-corrupted information-carrying events which are representative of the encoded binary information. An amount of noise corruption carried by one of these plurality of values is estimate...

The invention relates to a method for estimating an impulse response, and a receiver whose received signal is formed of bursts comprising a training sequence and the receiver comprising analog-to-digital converter for sampling the received signal and signal processor for measuring a DC offset in the samples. To simplify the receiver structure, the receiver comprises a calculating device for calculating the impulse response by correlating the samples taken with the training sequence before removi...

A pulse-shape estimator calculates an impulse response for the transmit and receive pulse-shaping filters in a mobile wireless terminal. The pulse-shape estimator receives a training signal that has passed through the pulse-shaping filters and known training symbols. Based on the actual received signal containing the training symbols and the expected received signal, the pulse-shape estimator estimates the impulse response of the pulse-shaping filters. The calculated impulse response may be used...

A highly modular PACS-based system that combines the advantages of Optical Frequency Division Multiplexing (OFDM) and Personal Access Communication System (PACS) with Time Division Multiple Access (TDMA) technology. The system is arranged to support high-speed (higher than the 32 kbps of PACS) wireless access services to fixed and mobile users. For example, nominal user data rates of 32-to-356 kbps are attainable, and ever the higher speed of 768 kbps is possible for short ranges.

A system employs a modified Jakes' fading model to generate a fading signal having substantially equivalent autocorrelation values for in-phase (I) and quadrature-phase (Q) components. A Walsh transform may be applied to generate multiple, uncorrelated I and Q components, for multiple fading signals. A complex Rayleigh fading signal according to the modified complex Jakes fading model is provided by a generator having M pairs of I and Q paths. Each pair of I and Q paths includes a corresponding ...

Methods, systems and receiver devices are provided which may provide improved receiver performance in obtaining estimates of the complex-valued baseband channel in the presence of colored baseband noise. In various embodiments of the present invention, systems and methods are provided in which, over each synchronization signal period or other determinate information window, the channel coefficients and the color of the baseband noise are concurrently estimated. Thus, both the channel coefficient...

A method and apparatus are disclosed for reducing the complexity of reduced state sequence estimation (RSSE) techniques for a given number of states while also reducing the critical path problem. The intersymbol interference due to the less significant tail taps of the channel impulse response is processed with a lower complexity cancellation algorithm using tentative decisions, while the intersymbol interference due to the more significant initial taps is processed with a more complex cancellat...

The invention relates to a method for the compensation of interference in a signal generated by discrete multitone modulation. The signal generated by discrete multitone modulation has a multiplicity of carrier frequencies, and each carrier frequency has a signal vector. An error signal vector is generated from a reference signal vector, which is a signal vector from the multiplicity of signal vectors. The error signal vector is added to each of the remaining signal vectors of the multiplicity o...

An adaptive notch filter (ANF) module selectively filters a received wideband communication signal to eliminate narrowband interference that lies within the frequency spectrum of the wideband communication signal. To determine the presence of narrowband interference, the ANF module scans various known narrowband channels that lie within the frequency spectrum of the wideband communication signal and determines signal strengths for each of the narrowband channels. The signal strengths from the na...

A communication system having a forward link and/or reverse link comprising: at least one base station which transmits multiple radio frequency (RF) signals; and a mobile station, the mobile station including: a receiver for receiving the RF signals; means for converting the RF signal to an intermediate frequency (IF) signal; means for sampling the IF signal to generate a digital signal, the digital signal having a data component and an interference component; means for canceling co-channel and ...