Abstract: An approach to clustering a set of images based on similarity measures employs a fuzzy clustering paradigm in which each image is represented by a node in a graph. The graph is ultimately partitioned into subgraphs, each of which represent true clusters among which the various images are distributed. The partitioning is performed in a series of stages by identifying one true cluster at each stage, and removing the nodes belonging to each identified true cluster from further consideration so that the remaining, unclustered nodes may then be grouped. At the beginning of each such stage, the nodes that remain to be clustered are treated as all belonging to a single candidate cluster. Nodes are removed from this single candidate cluster in accordance with similarity and connectivity criteria, to arrive at a true cluster. The member nodes of this true cluster are then removed from further consideration, prior to the next stage in the process.

Abstract: A transmitter and a receiver are disclosed herein that support transmit antenna diversity using space-time block coding in a wireless communication system. The transmitter produces symbol combinations containing, as their elements, input symbols, the inversions and conjugates of the symbols, and symbols obtained by rotating the phases of the symbols once, forms a matrix having symbols in at least two columns orthogonal to each other with the symbol combinations, and transmits the matrix. The receiver detects symbols that minimize maximum likelihood (ML) decoding metrics over all possible symbols using channel gains from transmit antennas to a receive antenna. Also, the receiver selects candidate symbols among all possible symbols according to the characteristics of transmitted modulation symbols and detects symbols that minimize the ML decoding metrics.

Abstract: A method and apparatus for increasing the data rate and providing antenna diversity using multiple transmit antennas is disclosed. A set of bits of a digital signal are used to generate a codeword. Codewords are provided according to a channel code. Delay elements may be provided in antenna output channels, or with suitable code construction delay may be omitted. n signals represent n symbols of a codeword are transmitted with n different transmit antennas. At the receiver MLSE or other decoding is used to decode the noisy received sequence. The parallel transmission and channel coding enables an increase the data rate over previous techniques, and recovery even under fading conditions. The channel coding may be concatenated with error correction codes under appropriate conditions.

Abstract: An apparatus and method for generating an effective Signal to Noise Ratio (SNR) per stream in a Multiple Input Multiple Output (MIMO) wireless communication system is disclosed. The apparatus includes a selector, a calculator, a generator, and a decider. The selector selects effective streams among whole streams. The calculator calculates a relative SNR rate between the effective streams. The generator generates an equation having as a solution an SNR of a first effective stream. The decider decides an SNR per effective stream using the solution of the equation and the relative SNR rate.

Abstract: An apparatus and a method for interference cancellation in a transmitting end of a multi-antenna system are provided. A precode is generated which maximizes a diversity gain of one or more receive antennas using channel information of the receive antennas to be serviced. Transmit powers of the receive antennas are updated by taking into account a power loss and a shaping loss according to a dirty paper coding. Transmit signals are precoded by updating the precode according to the updated transmit powers. The dirty paper coding is performed on the precoded transmit signals to be transmitted to the receive antennas.

Abstract: An approach to clustering a set of images based on similarity measures employs a fuzzy clustering paradigm in which each image is represented by a node in a graph. The graph is ultimately partitioned into subgraphs, each of which represent true clusters among which the various images are distributed. The partitioning is performed in a series of stages by identifying one true cluster at each stage, and removing the nodes belonging to each identified true cluster from further consideration so that the remaining, unclustered nodes may then be grouped. At the beginning of each such stage, the nodes that remain to be clustered are treated as all belonging to a single candidate cluster. Nodes are removed from this single candidate cluster in accordance with similarity and connectivity criteria, to arrive at a true cluster. The member nodes of this true cluster are then removed from further consideration, prior to the next stage in the process.

Abstract: Input signals of each frame are encoded by mapping the signals onto a coordinate system dictated by the symbols of the previous frame, and symbols from a constellation are selected based on the results of such mapping. Received signals are detected by preprocessing the signals detected at each antenna with signals detected by the antenna at the immediately previous frame, and then applied to a maximum likelihood detector circuit, followed by an inverse mapping circuit.

Abstract: The present Broadband Link System supplements the existing Air-To-Ground Radio Frequency communications link with an additional, separate high speed Broadband Ground-To-Air Data Channel to provide additional data communication capacity for aircraft. This Broadband Ground-To-Air Data Channel is typically a uni-directional (Ground-To-Air) link directed via a focused beam to selected aircraft which are operational in the coverage area of the Broadband Ground-To-Air Data Channel. The routing of the various data transmissions on both the Air-To-Ground Radio Frequency communications link and the Broadband Ground-To-Air Data Channel are managed in a unified manner to maximize the utilization of the two transmission facilities.

Abstract: An apparatus and method for removing interference in a transmitting end of a multi-antenna system are provided. The method includes receiving channel information for all Receive (Rx) antennas; calculating a beam-forming matrix that maximizes a Signal-to-Interference plus Noise Ratio (SINR) for each Rx antenna by using the received channel information; calculating an integer value which is in proportion to an interference signal for each Rx antenna by using the received channel information and the calculated beam-forming matrix, and performing Dirty Paper Coding (DPC) on a Transmit (Tx) signal by using the calculated integer value; and performing beam-forming by multiplying the Tx signal that has undergone the DPC by the calculated beam-forming matrix. Accordingly, a highest data rate for each user and a highest diversity can be obtained.

Abstract: The present invention relates to space-time coding techniques capable of providing incremental redundancy in wireless communication environments incorporating spatial and temporal diversity. In general, a transmitter sends packets, via blocks of symbols, to a receiver with high bandwidth efficiency and only in the event that the receiver does not correctly receive a data packet does the transmitter send additional symbols to assist with the decoding of the incorrectly received packet. A hybrid ARQ feedback mechanism is used such that the receiver can inform the transmitter whether the packets were correctly or incorrectly received. From the feedback, the transmitter can determine whether to send new symbols or initiate incremental redundancy.

Abstract: An electronic circuit for decoding wireless communication signals comprises: a combiner adapted to receive one of an incoming time diverse or frequency diverse signal representing blocks of encoded symbols. The blocks of symbols have been transmitted by a plurality of spatially diverse antennas. The combiner is configured to combine the received encoded symbols The received encoded symbols include negated selected symbols and conjugated selected symbols. A maximum likelihood detector is configured to receive the one of a time diverse or a frequency diverse signal. The detector receives the combined encoded signals and recovers transmitted signals using a channel transfer function.

Abstract: A transmitter and a receiver are disclosed herein that support transmit antenna diversity using space-time block coding in a wireless communication system. The transmitter produces symbol combinations containing, as their elements, input symbols, the inversions and conjugates of the symbols, and symbols obtained by rotating the phases of the symbols once, forms a matrix having symbols in at least two columns orthogonal to each other with the symbol combinations, and transmits the matrix. The receiver detects symbols that minimize maximum likelihood (ML) decoding metrics over all possible symbols using channel gains from transmit antennas to a receive antenna. Also, the receiver selects candidate symbols among all possible symbols according to the characteristics of transmitted modulation symbols and detects symbols that minimize the ML decoding metrics.

Abstract: A simple block coding arrangement is created with symbols transmitted over a plurality of transmit channels, in connection with coding that comprises only of simple arithmetic operations, such as negation and conjugation. The diversity created by the 5 transmitter utilizes space diversity and either time or frequency diversity. Space diversity is effected by redundantly transmitting over a plurality of antennas, time diversity is effected by redundantly transmitting at different times, and frequency diversity is effected by redundantly transmitting at different frequencies: Illustratively, using two transmit antennas and a single receive antenna, one of the disclosed embodiments provides the to same diversity gain as the maximal-ratio receiver combining (MRRC) scheme with one transmit antenna and two receive antennas.

Abstract: An apparatus and method for removing interference in a transmitting end of a multi-antenna system is provided. The method includes decomposing a channel matrix comprising channel coefficients for a plurality of terminals, calculating a value proportional to an interference signal for each of antennas, and calculating a sum of a transmission signal and the calculated value for each terminal and multiplying the calculated sum by the decomposed channel matrix. Accordingly, channel capacity can be improved by optimizing a data transfer rate and transmission power for each terminal.

Abstract: A simple block coding arrangement is created with symbols transmitted over a plurality of transmit channels, in connection with coding that comprises only of simple arithmetic operations, such as negation and conjugation. The diversity created by the 5 transmitter utilizes space diversity and either time or frequency diversity. Space diversity is effected by redundantly transmitting over a plurality of antennas, time diversity is effected by redundantly transmitting at different times, and frequency diversity is effected by redundantly transmitting at different frequencies: Illustratively, using two transmit antennas and a single receive antenna, one of the disclosed embodiments provides the to same diversity gain as the maximal-ratio receiver combining (MRRC) scheme with one transmit antenna and two receive antennas.

Abstract: An approach to clustering a set of images based on similarity measures employs a fuzzy clustering paradigm in which each image is represented by a node in a graph. The graph is ultimately partitioned into subgraphs, each of which represent true clusters among which the various images are distributed. The partitioning is performed in a series of stages by identifying one true cluster at each stage, and removing the nodes belonging to each identified true cluster from further consideration so that the remaining, unclustered nodes may then be grouped. At the beginning of each such stage, the nodes that remain to be clustered are treated as all belonging to a single candidate cluster. Nodes are removed from this single candidate cluster in accordance with similarity and connectivity criteria, to arrive at a true cluster. The member nodes of this true cluster are then removed from further consideration, prior to the next stage in the process.

Abstract: A method and apparatus for increasing the data rate and providing antenna diversity using multiple transmit antennas is disclosed. A set of bits of a digital signal are used to generate a codeword. Codewords are provided according to a channel code. Delay elements may be provided in antenna output channels, or with suitable code construction delay may be omitted. n signals represent n symbols of a codeword are transmitted with n different transmit antennas. At the receiver MLSE or other decoding is used to decode the noisy received sequence. The parallel transmission and channel coding enables an increase the data rate over previous techniques, and recovery even under fading conditions. The channel coding may be concatenated with error correction codes under appropriate conditions.

Abstract: According to one aspect of the present invention, there is provided a signal transmission apparatus for a mobile communication system. In the signal transmission apparatus, a frame segmentation section segments an input frame into Bk bit group, where k=1, . . . , K. A first group of encoders encodes Bk bit group and outputs encoded symbols. A second group of encoders encodes other Bk? bit group and output other encoded symbols. Each encoded symbol is encoded again to the transmit antennas using different functions. A transmission section includes a plurality of antennas in groups of a predetermined number of antennas, and the total number N of antennas is larger than the sum of the number of antenna groups. The transmission antennas transmit symbols encoded by one of the encoders.

Abstract: An approach to clustering a set of images based on similarity measures employs a fuzzy clustering paradigm in which each image is represented by a node in a graph. The graph is ultimately partitioned into subgraphs, each of which represent true clusters among which the various images are distributed. The partitioning is performed in a series of stages by identifying one true cluster at each stage, and removing the nodes belonging to each identified true cluster from further consideration so that the remaining, unclustered nodes may then be grouped. At the beginning of each such stage, the nodes that remain to be clustered are treated as all belonging to a single candidate cluster. Nodes are removed from this single candidate cluster in accordance with similarity and connectivity criteria, to arrive at a true cluster. The member nodes of this true cluster are then removed from further consideration, prior to the next stage in the process.

Abstract: A simple block coding arrangement is created with symbols transmitted over a plurality of transmit channels, in connection with coding that comprises only of simple arithmetic operations, such as negation and conjugation. The diversity created by the transmitter utilizes space diversity and either time or frequency diversity. Space diversity is effected by redundantly transmitting over a plurality of antennas, time diversity is effected by redundantly transmitting at different times, and frequency diversity is effected by redundantly transmitting at different frequencies. Illustratively, using two transmit antennas and a single receive antenna, one of the disclosed embodiments provides the same diversity gain as the maximal-ratio receiver combining (MRRC) scheme with one transmit antenna and two receive antennas.