Abstract: The present invention relates to employing OFDM modulation in combination with spatial diversity and space-time block coding to provide high data rates and exceptional interference immunity. For transmission, quadrature modulated data is encoded in space and time to create individual series of encoded symbols. Each of these series of encoded symbols is subjected to a type of inverse Fourier Transform in corresponding transmission paths. In each transmission path, cyclic extensions may be appended to the resultant symbols, which are subsequently converted to an analog format, modulated, amplified, and transmitted from one of multiple antennas. Preferably, such communications are implemented from base stations to mobile terminals in an environment where the frequency reuse factor is approximately one and the base stations are synchronized to a common clock signal.

Abstract: The present invention relates to employing OFDM modulation in combination with spatial diversity and space-time block coding to provide high data rates and exceptional interference immunity. For transmission, quadrature modulated data is encoded in space and time to create individual series of encoded symbols. Each of these series of encoded symbols is subjected to a type of inverse Fourier Transform in corresponding transmission paths. In each transmission path, cyclic extensions may be appended to the resultant symbols, which are subsequently converted to an analog format, modulated, amplified, and transmitted from one of multiple antennas. Preferably, such communications are implemented from base stations to mobile terminals in an environment where the frequency reuse factor is approximately one and the base stations are synchronized to a common clock signal.

Abstract: A wireless communication system is provided which transmits and receives Multiple-Transmit Multiple-Receive (MTMR) signal in which the superimposed substreams of the received MTMR signal are recovered by concurrently estimating all of the substreams of the transmitted signal. A plurality of estimated data symbols are defined as a function of the plurality of signal samples. A difference expression that represents a difference between a function of a plurality of estimated data symbols and a function of the plurality of signal samples is determined and is a sum of plurality of terms. Values for each of a portion of a plurality of estimated data symbols are repeatedly selected such that one of the plurality of terms is minimized. Values for a further portion of the plurality of estimated data symbols are repeatedly selected such that a further one of the plurality of terms is minimized.

Abstract: A method of estimating the sequence of transmitted symbols in a digital communication system is provided. By assuming that the transmitted symbols have a zero mean and a covariance matrix given by an identity matrix, as is the case in an EDGE communication system, the solution to the minimization of the expectation value of ∥{circumflex over (s)}−s∥2 always allows a lower triangular matrix to be found through Cholesky decomposition. The lower triangular matrix allows an efficient block decision-feedback sequence estimation to be carried out. The method is no more complex than the zero-forcing block decision-feedback sequence estimation technique, yet a solution always exists and performance is improved over the zero-forcing method.

Abstract: A diversity hybrid receiver structure is provided for estimating the sequence of transmitted symbols in a digital communication system. A joint optimizer determines optimal effective channel coefficients for use by an equalizer using a power method, and determines optimal filter coefficients for use by a space-time filter. The space-time filter mitigates co-channel interference and produces an intermediate sequence of signal samples. The equalizer acts on the intermediate sequence of signal samples and corrects for intersymbol interference to estimate the transmitted sequence of symbols. The equalizer uses an efficient block decision-feedback sequence estimation method. An interference detection scheme is also provided.

Abstract: The present invention relates to employing OFDM modulation in combination with spatial diversity and space-time block coding to provide high data rates and exceptional interference immunity. For transmission, quadrature modulated data is encoded in space and time to create individual series of encoded symbols. Each of these series of encoded symbols is subjected to a type of inverse Fourier Transform in corresponding transmission paths. In each transmission path, cyclic extensions may be appended to the resultant symbols, which are subsequently converted to an analog format, modulated, amplified, and transmitted from one of multiple antennas. Preferably, such communications are implemented from base stations to mobile terminals in an environment where the frequency reuse factor is approximately one and the base stations are synchronized to a common clock signal.