Abstract: A signal detecting method and a receiver using the same are provided. The method includes the following steps. A receiving signal vector y is received through a number of channels, wherein the receiving signal vector y corresponds to a transmitting signal vector x transmitted by at least one of the channels. A channel matrix H is determined, wherein the channel matrix H represents at least one of the channels. A factorization matrix D is chosen, wherein D is invertible to make the channel matrix H expressed as H={tilde over (H)}D, and {tilde over (H)} is a corresponding channel matrix. The factorization matrix D is determined to make an expected value of the signal estimate error become smaller. The receiving signal vector y is detected to estimate the transmitting signal vector x according to the corresponding channel matrix {tilde over (H)} and the factorization matrix D.

Abstract: An apparatus for generating a 2D spreading code and method for the same are proposed. The apparatus for generating the 2D spreading code includes a column counter, a row counter, a codeword selector, and a logic unit. The logic unit performs logic operations on the output of the column counter, the row counter, and the codeword selector to generate the 2D spreading code of desired order designated by the codeword selector. The 2D spreading code includes 4 2×2 initial matrixes for generating 4i codes for 4i users in the ith order. The apparatus for generating the 2D spreading code according to the present invention is advantageously used in OFDM system to increase the number of subscribers with reduced interference.

Abstract: A method of performing a handover process in a wireless multi-hop communication network, the method comprising requesting neighborhood communication information regarding channel condition among access stations in the neighborhood of a mobile station, the neighborhood communication information including communication information related to a link between a first station and a second station in the wireless multi-hop communication network, obtaining the communication information related to the link between the first station and the second station, sending the communication information from the first station to a mobile station in the wireless multi-hop communication network, and configuring the mobile station based on the communication information so as to switch the mobile station to the second station.

Abstract: Methods and apparatuses for reception of point-to-multipoint (PTM) transmissions in a wireless communication system including a set of receiving devices. The method includes receiving location information respectively associated with each of a plurality of PTM data versions, and retrieving the plurality of PTM data versions using the location information. The method also includes combining the retrieved plurality of PTM data versions to generate a combined PTM data version, and decoding the combined PTM data version.

Abstract: An apparatus for data processing in a multi-channel communication system is provided. The apparatus includes an encoder configured to encode a number of bits for transmission via channels in the multi-channel communication system into coded bits and split the coded bits into a number of first sets of bits at a first ratio, a number of first rate units coupled to the encoder, each of the first rate units being configured to adjust one set of the first sets of bits in size at at least one rate, and a controller configured to assign the first ratio to the encoder and the at least one rate to each of the first rate units based on conditions of the channels.

Abstract: A method of constructing a frame structure for data transmission, the method comprising generating a first section comprising data configured in a first format compatible with a first communication system, generating a second section following the first section, the second section comprising data configured in a second format compatible with a second communication system, wherein the second format is different from the first format, generating at least one non-data section containing information describing an aspect of data in at least one of the first section and the second section, and combining the first section, the second section and the at least one non-data section to form the frame structure.

Abstract: A method forms a preamble sequence in a wireless communication system.

Abstract: At the transmitter of a transmitter and receiver apparatus for Multiple Input/Multiple Output MultiCarrier-Code Division Multiple Access (MIMO MC-CDMA) systems, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. As a result, space, time, and frequency diversity can be explored.

Abstract: A system and method for identifying a resource region including a plurality of symbols, allocating pilot signals to the resource region, identifying pilot-free symbols free of the pilot signals in the plurality of symbols, arranging sacrifice carriers for a first region of a group of symbols in the pilot-free symbols at a first density for a first communication station, and arranging sacrifice carriers for a second region of the group of symbols in the pilot-free symbols at a second density for a second communication station, the first communication station mobile with respect to an access communication station at a first relative speed and the second communication station is mobile with respect to the access communication station at a second relative speed, and wherein the first density of sacrifice carriers is greater than the second density of sacrifice carriers if the first relative speed is greater than the second relative speed.

Abstract: The invention relates to an apparatus of transmitter and receiver for MIMO MC-CDMA systems. At the transmitter, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. Upon the invention, the space, time, and frequency diversity can be explored.

Abstract: The invention relates to an apparatus of transmitter and receiver for Multiple Input/Multiple Output MultiCarrier-Code Division Multiple Access (MIMO MC-CDMA) systems. At the transmitter, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. Upon the invention, the space, time, and frequency diversity can be explored.

Abstract: An equalization method suitable for use in a receiver in an orthogonal frequency division multiplexing (OFDM) system utilizing a plurality of sub-carriers. The receiver includes an outer receiver for decoding. The equalization method includes receiving an input signal including at least one preamble symbol containing a training sequence and a plurality of informative OFDM symbols each containing a serial stream of samples, and performing compensations for each of the informative OFDM symbols. Compensation for each of the informative OFDM symbols includes converting the serial stream of samples into parallel samples, performing a fast Fourier transform (FFT) of the parallel samples to obtain a plurality of data symbols, each data symbol corresponding to a sub-carrier, compensating the data symbols for at least one first phase distortion and at least one second phase distortion, and providing at least one amplitude distortion factor to the outer receiver.

Abstract: An orthogonal frequency division multiplexing (OFDM) system provided for communication includes an OFDM transmitter and an OFDM receiver. The OFDM transmitter may be configured to transmit OFDM signals through a communication channel and may include a channel encoder configured to encode a plurality of information bits and an interleaver configured to interleave the channel-encoded information bits. The OFDM transmitter may also include a mapper configured to map the interleaved channel-encoded information bits into mapped multi-level symbols. The OFDM transmitter may also include a dispersive encoder that is configured to dispersively encode the mapped symbols. The OFDM receiver may be configured to receive the transmitted OFDM signals and to decode the received OFDM signals iteratively based on soft decision methods.

Abstract: An apparatus for generating a 2D spreading code and method for the same are proposed. The apparatus for generating the 2D spreading code includes a column counter, a row counter, a codeword selector, and a logic unit. The logic unit performs logic operations on the output of the column counter, the row counter, and the codeword selector to generate the 2D spreading code of desired order designated by the codeword selector. The 2D spreading code includes 4 2×2 initial matrixes for generating 4i codes for 4i users in the ith order. The apparatus for generating the 2D spreading code according to the present invention is advantageously used in OFDM system to increase the number of subscribers with reduced interference.

Abstract: An equalization method suitable for use in a receiver in an orthogonal frequency division multiplexing (OFDM) system utilizing a plurality of sub-carriers. The receiver includes an outer receiver for decoding. The equalization method includes receiving an input signal including at least one preamble symbol containing a training sequence and a plurality of informative OFDM symbols each containing a serial stream of samples, and performing compensations for each of the informative OFDM symbols. Compensation for each of the informative OFDM symbols includes converting the serial stream of samples into parallel samples, performing a fast Fourier transform (FFT) of the parallel samples to obtain a plurality of data symbols, each data symbol corresponding to a sub-carrier, compensating the data symbols for at least one first phase distortion and at least one second phase distortion, and providing at least one amplitude distortion factor to the outer receiver.

Abstract: The invention relates to an apparatus of transmitter and receiver for MIMO MC-CDMA systems. At the transmitter, modified orthogonal transmit diversity (MOTD) encoders are used for increasing space and time transmission diversity. A P-way combiner is used to connect the MOTD encoders and P multi-carrier modulators. Each modulator is connected to a set of antennas. At the receiver, each multi-carrier demodulator has an amplitude/phase compensator to compensate distortion at every sub-carrier. Similarly, a combiner is used to connect the demodulators and the MOTD decoders. Upon the invention, the space, time, and frequency diversity can be explored.