Abstract: The present invention discloses a method and system for signal communication in a multi-input multi-output network. The method creates beamformed channels by calculating one or more beamforming weighting vectors corresponding to one or more antennas on the receiving wireless station based on the predetermined receiving signals. The transmitting wireless station transmits one or more beamformed transmission signals to the receiving wireless station using the calculated beamforming weighting vectors for targeting at the antennas thereon, thereby creating two or more detectably uncorrelated transmission signals received at the receiving wireless station.

Abstract: The present invention discloses a wireless communications system with reduced sideband noise and carrier leakage. In the system, at least one transmitter modulates at least one input signal with a first carrier to generate a modulated output signal, and at least one receiver receives the modulated output signal and demodulates the same with a second carrier to generate at least one demodulated output signal. The first and second carriers are at different frequencies, such that the sideband noise and carrier leakage generated by different sources can be distinguished.

Abstract: This invention discloses a method for performing soft detection of transmitted signals modulated by M-QAM when a transmitter equipped with one or more transmit antennas, and the receiver has one or more receive antennas. This invention is built based on the fact that soft value of a single transmitted bit (or symbol) has a piece-wise linear behavior as a function of the received signal(s). The methodology to obtain such piece-wise linear functions are given for some M-QAM modulations in single transmit and single receive antenna systems and arbitrary constellation mapping. Also, the methodology is explained for the case where the number of transmit antennas is more than one by an example for 4-QAM modulation and two transmit antennas. A further required process to expand above embodiments to multiple receive antennas are also given.

Abstract: A method for decoding tail-biting convolutional codes is disclosed. In the method, all beginning states of a trellis diagram are initialized. Forward Viterbi metrics are calculated for the trellis diagram. A trace-back process is performed from an ending state of the trellis diagram at a first time instance to a first state where all surviving paths converge at a second time instance. Backward Viterbi metrics are calculated for a predetermined period of time from the first state at the second time instance to a second state at a third time instance. A trace-back process is performed from a designated state, which is equal to the second state, at the first time instance to determine a most likely path for the convolutional codes in the trellis diagram.