Agency for Science, Technology and Research

National University of Singapore

Ying Chang Liang

Zhongding Lei

Sumei Sun

Chin Keong Ho

Po Shin Francois Chin

Yan Wu

Ho Wang Fung

Yong Hong Zeng

Yonghong Zeng

Francois Po Shin Chin

Anh Tuan Hoang

Ashok Kumar Marath

Jitvanichphaibool Kommate

According to embodiments of the present invention, a method for identifying one or more frequency bands in a received signal. The method comprising: calculating a wavelet product of the received signal; setting a threshold for local maxima of the wavelet product; and detecting one or more edges in the received signal based on local maxima of the wavelet product which are greater than the threshold to identify one or more frequency bands in the received signal. A corresponding apparatus and computer program product are also provided. Embodiments also relate to a method for evaluating performance of a method for identifying one or more frequency bands in a received signal. A corresponding apparatus and computer program product are also provided.

Method, apparatus and computer program product for identifying frequency bands, and a method, apparatus and computer program product for evaluating performance

A method for spectrum sensing is described comprising receiving a signal using a plurality of receive antennas; forming a set of received signals including the received signal of each antenna; determining a cyclic auto-correlation of the set of received signals; estimating, for each receive antenna, channel state information of the radio channel via which the receive antenna receives the signal based on the determined cyclic auto-correlation; performing maximum ratio combining of the received signal samples based on the estimated channel state information; determining a measure of the cyclostationarity of the received signal based on the result of the maximum ratio combining; and performing cyclostationarity detection spectrum sensing based on the determined measure of the cyclostationarity of the received signal.

Method for spectrum sensing and communication device

A method of determining available frequency ranges for at least one communication device is provided. The method comprises providing a downlink transmission time interval, determining available frequency ranges within a plurality of frequency ranges after the downlink transmission time interval, and providing an uplink transmission time interval after the determining of the available frequency ranges.

Method and devices for determining available frequency ranges

A method of allocating frequency ranges to at least one communication device is provided. The method comprises determining available frequency ranges within a plurality of frequency ranges, combining the available frequency ranges to at least one combined logical frequency range, and allocating the at least one combined logical frequency range to the at least one communication device.

Methods and devices for allocating frequency ranges

A method of determining a residual frequency offset between a transmitter and a receiver in a transmission of data via a communication channel, is described, wherein the message is transmitted from the transmitter to the receiver via the communication channel and the message comprises at least one short preamble (), at least one long preamble () and user data (). The at least one long preamble () comprises residual frequency offset determination information based on which the residual frequency offset is determined.

Method for determining a residual frequency offset, communication system, method for transmitting a message, transmitter, method for processing a message and receiver

A method for transmitting a digital signal is described, wherein the digital signal is to be transmitted by a plurality of antennas and a 2-domain pre-transformation is carried out, i.e., in course of a pre-transformation modulation symbols assigned to subcarriers having different frequencies and assigned to subcarriers sent by different antennas are linearly combined.

Method for transmitting a digital data stream, transmitter, method for receiving a digital data stream and receiver

A transmitter that has a determination unit for determining a plurality of symbols () such that each symbol () has a tail component () and the plurality is determined in such a way that the tail components () are substantially equal and a tone generation unit for arranging the plurality of symbols () to form a plurality of long preambles () such that the plurality of long preambles () are tone-interleaved.

Transmitter, method for generating a plurality of long preambles and communication device

A method for equalizing a digital signal received via at least one communication channel is described, wherein a block of received signal values is processed by a block-iterative equalizer (). The equalizer comprises a feedback unit () and a feed-forward unit () each corresponding to the multiplication by a respective matrix. The matrices are updated in the iterative process.

Method for equalizing a digital signal and equalizer

A scheme for selecting two beams in a switched beam antenna system for providing downlink communications in a downlink channel, the switched beam antenna system providing uplink reception and downlink transmission is described. The scheme involves selecting a pair of beams based on the uplink reception of the switched beam antenna system, and determining from the pair of beams a corresponding pair of orthogonal beams. The scheme also involves providing the pair of orthogonal beams as a pair of transmit beams for the downlink transmission of the switched beam antenna system.

Method for selecting switched orthogonal beams for downlink diversity transmission

A method for downlink capacity enhancement in a wireless communications system that has a base station with antenna array and terminals that are physically remote from the base station comprises the steps of receiving at the base station antenna array combinations of arriving signals from the plurality of remote terminals, estimating an uplink channel covariance matrix (UCCM) for each of the terminals from the combinations of arriving signals, constructing from each UCCM a downlink channel covariance matrix (DCCM), calculating from the DCCM a downlink weight vector for each of the terminals, transmitting a set of information signals from the base station antenna array according to the downlink weight vectors.

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Singapore, Singapore

Ying Chang Liang