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: A method and system are provided for improving the performance of a trellis-based decoder. States with reduced uncertainty (SRUs) are defined for one or more predetermined fields in an encoded message. Metrics are set for the SRUs such that candidate paths through a trellis-based decoding process are eliminated for those states that are not SRUs.

Abstract: Techniques are provided to compute the carrier to interference-plus-noise ratio (CINR) in a wireless communication system using log-likelihood ratio (LLR) data generated from a received transmission. The LLR data are collected as they are sent from a detector to a forward error correction (FEC) decoder in a wireless communications device. In one embodiment, decision-aided LLR based CINR is computed using the decoded bits output from the FEC decoder as feedback. In another embodiment, blind LLR based CINR is computed without feedback. The CINR may be used to adjust a modulation and/or coding parameters associated with wireless communication between wireless communication devices.

Abstract: Method and system are provided for improving the performance of a trellis-based decoder. States with reduced uncertainty (SRUs) are defined for one or more predetermined fields in an encoded message. Metrics are set for the SRUs such that candidate paths through a trellis-based decoding process are eliminated for those states that are not SRUs.

Abstract: Techniques are provided to enable wireless communication between first and second wireless communication devices each having a plurality of antennas, where the second device sends the transmissions via less than all of its plurality of antennas. Each transmission may comprise a plurality of time-frequency instances. At the first communication device, data is derived representing parameters of a communication channel between the plurality of antennas of the first device and all of the plurality of antennas of the second device from the transmissions received at the plurality of antennas of the first device. Beamforming weights for transmitting one or more signal streams via the plurality of antennas of the first device to the plurality of antennas of the second device are computed based on the data representing parameters of the communication channel between the plurality of antennas of the first device and the plurality of antennas of the second device.

Abstract: Techniques are provided herein to improve the decoding efficiency in a wireless receiver to obtain a correctly decoded data string. A state metric matrix from a received codeword is used to generate active state metric matrices for time instances of the received codeword, and then a differential metric matrix is generated from information in the active state metric matrices. Based on the differential metric matrix a maximum likelihood path and one or more alternative paths are identified. A first decoded data string corresponding to the maximum likelihood path and a plurality of second decoded data strings corresponding to the one or more alternative paths are derived. Integrity of the respective decoded data strings is examined to obtain the correct decoded data string based on the first and second decoded data strings.

Abstract: A system for detecting one or more localized burst errors in a receiving message comprised of a plurality of codewords. The system comprises a trellis code decoder for decoding a receiving message with a plurality of codewords and calculating one or more cumulative metrics of a maximum likelihood path and one or more alternative paths from the receiving message, an error detection code (EDC) decoder for detecting existence of one or more errors in the decoded receiving message received from the trellis decoder, and a localized burst error detector activated by the EDC decoder upon detecting the existence of one or more errors in the decoded receiving message to identify at least one corrupted codeword among the plurality of codewords using the one or more cumulative metrics of a maximum likelihood path and the one or more alternative paths, wherein the system requests the re-transmission of the corrupted codeword.

Abstract: A system for detecting one or more localized burst errors in a receiving message comprised of a plurality of codewords. The system comprises a trellis code decoder for decoding a receiving message with a plurality of codewords and calculating one or more cumulative metrics of a maximum likelihood path and one or more alternative paths from the receiving message, an error detection code (EDC) decoder for detecting existence of one or more errors in the decoded receiving message received from the trellis decoder, and a localized burst error detector activated by the EDC decoder upon detecting the existence of one or more errors in the decoded receiving message to identify at least one corrupted codeword among the plurality of codewords using the one or more cumulative metrics of a maximum likelihood path and the one or more alternative paths, wherein the system requests the re-transmission of the corrupted codeword.

Abstract: Apparatus, system, and method for an adaptive transmission selection technique. A retransmission scheme is selected for a multiple-input-multiple-output (MIMO) wireless communications system. Techniques are provided herein for selecting from a plurality of wireless communication techniques when a first device needs to retransmit a signal (one or more packets of data) to a second device. The first device determines when the signal which was originally wirelessly transmitted using beamforming techniques via multiple antennas of the first device to the second device needs to be retransmitted to the second device. If a retransmission is needed, the first device determines channel conditions with respect to the second device. The first device selects a retransmission scheme from a plurality of transmission schemes based on the channel conditions for retransmitting the signal via the multiple antennas of the first device to the second device.

Abstract: A method and system are provided for achieving spatial diversity of a wireless communications network. The method comprises arranging antennas on a transmitting wireless station into a plurality of antenna subgroups, wherein each of the antenna subgroups forms a virtual antenna, creating a plurality of beamformed MIMO channels using the plurality of virtual antennas, wherein each of the beamformed MIMO channel comprises a plurality of sub-carriers and corresponds to a virtual antenna, dividing sub-carriers in each of the plurality of beamformed MIMO channels into at least a first and second cluster, distributing a first amount of transmitting power to the first cluster and a second amount of transmitting power to the second cluster, wherein the first amount of transmitting power is substantially larger than the second amount of transmitting power.

Abstract: The present invention discloses a method for retransmitting a data sequence according to channel condition in a wireless communications network. The method comprises transmitting a first transmitting signal representing the data sequence using a first set of beamforming weighting vectors generated according to a first channel condition, receiving a request for re-transmitting the data sequence, wherein the first transmitting signal suffers from unrecoverable errors, computing a re-transmission function according to a second channel condition, and transmitting a second transmitting signal generated by using the re-transmission function that is created according to the second channel condition, wherein the data sequence is demodulated and decoded using the first transmitting and the second transmitting signals.

Abstract: The present invention discloses a method for generating a signal stream in a multiple-input-multiple-output (MIMO) channel of a wireless communications system. The method comprises encoding at least one transmitting message into a first signal sequence, transforming the first signal sequence into a second and a third signal sequence by a first and a second predetermined rule, respectively, coupling the second signal sequence to a first antenna, coupling the third signal sequence to a second antenna, transmitting a signal stream comprising the first and second signal sequences to a mobile station.

Abstract: A method for partitioning a plurality of antennas in a wireless communication system, in which the antennas are grouped into a first set of partitions and a second set of partitions. One or more signal transmission schemes are performed with the antennas grouped into the first set of partitions for a first time period, and then with the antennas grouped into the second set of partitions for a second time period.

Abstract: A method for providing a fast fading channel in a MIMO communication system is disclosed. The method includes encoding a series of source data to generate a first plurality of encoded output signals and multiplying the first plurality of encoded output signals by a plurality of random complex numbers to generate a second plurality of encoded output signals, and transmitting the second plurality of encoded output signals via the corresponding plurality of antennas, wherein the transmitting signals vary in time and frequency independent of the channel conditions.

Abstract: The present invention discloses a method and system for improving the decoding efficiency in a wireless receiver to obtain a correct decoded data string. The method comprises generating an active state metric matrix of a receiving codeword, calculating a differential metric matrix pertinent to the active state metric matrix, identifying a maximum likelihood path and one or more alternative paths based on the differential metric matrix, deriving a first decoded data string corresponding to the maximum likelihood path, deriving a plurality of second decoded data strings corresponding to the one or more alternative paths, respectively examining the integrity of the first decoded data string; and examining the integrity of the plurality of second decoded data strings after the first decoded data string is determined erroneous, wherein the wireless receiver obtains the correct decoded data string.

Abstract: A system for detecting one or more localized burst errors in a receiving message comprised of a plurality of codewords. The system comprises a trellis code decoder for decoding a receiving message with a plurality of codewords and calculating one or more cumulative metrics of a maximum likelihood path and one or more alternative paths from the receiving message, an error detection code (EDC) decoder for detecting existence of one or more errors in the decoded receiving message received from the trellis decoder, and a localized burst error detector activated by the EDC decoder upon detecting the existence of one or more errors in the decoded receiving message to identify at least one corrupted codeword among the plurality of codewords using the one or more cumulative metrics of a maximum likelihood path and the one or more alternative paths, wherein the system requests the re-transmission of the corrupted codeword.

Abstract: The present invention discloses a method for obtaining a downlink beamforming weighting vector in a wireless communications system based on channel information about an uplink channel. The method comprises obtaining the channel information about the uplink channel by a means selected from the group comprising of training signals, pilot signals, and data signals, wherein the uplink channel comprises a set of uplink sub-channels, calculating a spatial signature of the uplink channel with the channel information, and computing a downlink beamforming weighting vector of a downlink channel with the spatial signature of the uplink channel, wherein the downlink channel comprises a set of downlink sub-channels that share few or no sub-carriers with the set of uplink sub-channels.

Abstract: The present invention discloses a method and system for improving the performance of a trellis-based decoder. The method comprises generating a first state with reduced uncertainty (SRU) and one or more second SRUs with one or more predetermined fields in a message; setting metrics of one or more states in the first SRU, which have an equal probability, to a first predetermined value; setting metrics of one or more states that are not in the first SRU to a second predetermined value, which corresponds to a minimum probability; and decoding the message while eliminating invalid candidate paths in a trellis by setting the metrics of the one or more states not belonging to the one or more second SRUs to a value corresponding to the second predetermined value.

Abstract: The present invention discloses a method and system for receive signal diversity combining that achieves the high effective SNR and high coding gain. The receive signal diversity combining method combines two or more received diversified signals of a predetermined original message and employs a Maximum Likelihood (ML) detection method to process the diversified signals to generate Log-Likelihood Ratio (LLR) data to exploit the available signal diversity and coding gain of each bit and to help the channel decoder to correctly determine the predetermined original message.

Abstract: The present invention discloses a method and system for detecting messages using enhanced distributed signaling in a wireless communication network that offers transmission diversity to improve the throughput of participating wireless stations.