Abstract: A system and method for communicating data includes an inner encoder for encoding data with the recursive inner rate one code. A modulator coherently modulates a communications signal that carries the data that has been encoded. An interleaver is operative with the inner encoder and modulator to aid in removing correlation of multipath fading channels on consecutive bits. A convolutional encoder is followed by a random interleaver. The modulator can be operative with mini-probe sequences. An equalizer and decoder receives the communications signal and iteratively decodes any recursive inner rate one code and convolutional code in a turbo fashion.

Abstract: A system and method for communicating data includes an inner encoder for encoding data with the recursive inner rate one code. A modulator coherently modulates a communications signal that carries the data that has been encoded. An interleaver is operative with the inner encoder and modulator to aid in removing correlation of multipath fading channels on consecutive bits. A convolutional encoder is followed by a random interleaver. The modulator can be operative with mini-probe sequences. An equalizer and decoder receives the communications signal and iteratively decodes any recursive inner rate one code and convolutional code in a turbo fashion.

Abstract: A decoding device may include a sequential convolutional code decoder, and a parallel convolutional code decoder. The decoding device may further include a controller for selectively processing a convolutionally encoded input signal via at least one of the sequential convolutional code decoder and the parallel convolutional code decoder. The selection of decoder may be based upon a signal-to-noise ratio or the passage of time, for example.

Abstract: The communication method includes the use of CRC codes for additional error correaction in addition to the error detection capability. The method is for error detection and correaction in a received message that includes N message bits and M Cyclic Redundancy Check (CRC) bits appended thereto. It is determined whether at least one bit error has occurred in the N message bits and M CRC bits of the received message based upon the M CRC bits, and when at least one bit error is determined, then K bits with a lowest quality metric are selected from the N message bits and M CRC bits. The bit error is corrected based upon possible bit error patterns and the selected K bits. Multiple bit errors may also be corrected.

Abstract: A communications system of the present invention includes a transmitter that is operative for combining an orthogonal Walsh modulation with a minimum shift keying or Gaussian minimum shift keying waveform to form a hybrid communications signal that carries communications data over a constant amplitude waveform that is spread in time and frequency. This communications signal can be transmitted to a RAKE receiver that has a plurality of correlators with output weights formed for processing this hybrid communications signal.

Abstract: A system communicates data and includes an encoder for encoding communications data with a forward error correction code. A data randomizer randomizes the communications data with a random bit sequence and a combining circuit combines the communications data with known symbols into frames. A modulator maps the communications data into minimum shift keying or Gaussian minimum shift keying (MSK or GMSK) symbols based on a specific mapping algorithm to form a communications signal having an MSK or GMSK waveform over which the communications data can be transmitted.

Abstract: A system and method for communicating data includes an inner encoder for encoding data with the recursive inner rate one code. A modulator coherently modulates a communications signal that carries the data that has been encoded. An interleaver is operative with the inner encoder and modulator to aid in removing correlation of multipath fading channels on consecutive bits. A convolutional encoder is followed by a random interleaver. The modulator can be operative with mini-probe sequences. An equalizer and decoder receives the communications signal and iteratively decodes any recursive inner rate one code and convolutional code in a turbo fashion.

Abstract: A wireless communications device may include a wireless receiver receiving wireless signals having alternating known and unknown symbol portions over a channel, and a demodulator systolic array connected to the wireless receiver.

Abstract: A wireless communications device may include a wireless receiver for receiving signals comprising alternating known and unknown symbol portions, and a demodulator connected thereto.

Abstract: In accordance with the present invention, the system and method removes interfering signals from a communications signal and includes a Fast Fourier Transform (FFT) circuit for taking the FFT of a received signal and segmenting the signal into segments. A frequency shifting circuit can shift each segment in frequency to place an interfering signal within a single FFT band to be later substantially nulled. An inverse FFT circuit can place the segments of signals back within the time domain.

Abstract: A wireless communications device may include a wireless transmitter, a modulator connected to the wireless transmitter, and a white Gaussian noise generator connected to the modulator. The white Gaussian noise generator may include at least one pseudorandom number generator, and a fast Walsh transform module for generating white Gaussian noise based upon the pseudorandom numbers.

Abstract: A wireless communications device which may include a wireless receiver for receiving wireless signals comprising unknown data portions over a channel, and a demodulator connected to the wireless receiver. The demodulator may be for estimating a delay spread and a fade rate associated with the channel, determining a desired time-domain interpolation filter based upon the estimated fade rate, and determining a desired frequency-domain interpolation filter based upon the estimated delay spread. The demodulator may further generate channel estimates for the unknown data portions based upon the desired time-domain interpolation filter and the desired frequency-domain interpolation filter, and determine the unknown data portions based upon the channel estimates.

Abstract: A signal generator generates a coded or memory waveform having a trellis structure. A modulator is operative with the signal generator for adding at least one phase pulse to the trellis structure of the coded or memory waveform to create a substantially constant envelope modulated signal that increases the transmitted bits per symbol.

Abstract: A system and method of the present invention forms a hybrid encoded signal. A signal generator generates a coded waveform having a trellis structure, such as a continuous phase modulated signal. A modulator is operative with the signal generator and adds at least one orthogonal or amplitude modulated waveform to a trellis structure of the coded waveform to create a non-constant envelope modulated signal that has at least one of increased bandwidth, improved bit error rate, or an increased number of bits encoded into a single symbol.

Abstract: A low complexity equalizer and its architecture are disclosed. The low complexity equalizer can identify and remove intersymbol interference caused by digital filters, analog filters, communication channel, channel-filtering and matched-channel filtering of the original transmitted signal.

Abstract: Disclosed is an inventive system and method for extracting signal energy from the guard time portion of a communication frame based on the amount of multipath interference experienced by that communication frame. In one embodiment, N blocks of samples are created from the received frame wherein the samples in the guard time portion of the received frame are included in one of more of the N blocks of samples. The estimated symbols, or estimated bits, determined from the received samples are checked for corruption due to multipath interference. For those blocks for which multipath interference is not detected, the estimated symbols, or estimated bits, are coherently added together so as to take advantage of uncorrupted signal energy from the guard time portion of the frame.

Abstract: A method for eliminating sinusoidal noise without affecting the response of the formation means that the actual formation responses of the logging tools are recovered, and the logs can be used quantitatively. Removal of sinusoidal noise from a log is accomplished in three steps. First, the log is reduced to a zero-mean, stationary series. Second, the wavenumber of the sinusoidal noise is identified by its peak in the Fourier amplitude spectrum. And third, the noise is removed by applying a zero-phase notch filter. In order to preserve the quantitative data integrity, the low wavenumber trend is kept. Preserving the quantitative data integrity is accomplished by approximating the log with a least-squares cubic spline which retains the overall log character, ignoring the sinusoidal noise. A zero mean stationary series is formed by subtracting the least-squares cubic spline from the data. The remaining steps, Fourier analysis and filtering are performed on the difference series.