Agency for Science, Technology and Research

Ntt Docomo, Inc.

National University of Singapore

National Univ. of Singapore

Francois Po Shin Chin

Zhongding Lei

Xiaoming Peng

Ying-Chang Liang

Mamoru Sawahashi

Yoshihisa Kishiyama

Kazuaki Takeda

Tetsushi Abe

Motohiro Tanno

Hiroyuki Atarashi

Daisuke Nishikawa

Chin Keong Ho

Ying Chang Liang

Jian Zhao

Xianming Qing

Sai Ho Wong

Xinyi Tang

Behrouz Farhang-Boroujeni

There is provided a beam steerable antenna system including: an antenna array including a plurality of first radiating elements; a first phase control section coupled to the plurality of first radiating elements, the first phase control section being configured to control a phase of signals from the plurality of first radiating elements to output first phase controlled signals; a first combiner coupled to the first phase control section, the first combiner being configured to combine the first phase controlled signals to output a first combined signal; a first frequency converter coupled to the first combiner, the first frequency converter being configured to downconvert a frequency of the first combined signal to output a first downconverted signal; and a second phase control section coupled to the first frequency converter, the second phase control section being configured to control a phase of the first downconverted signal to output a second phase controlled signal. There is also provided a method of manufacturing the beam steerable antenna system, and a method of beam steering an antenna array.

Beam steerable antenna system, method of manufacturing thereof and method of beam steering an antenna array

The objective of the invention is to suppress, in a case of applying the RRH system in an environment having a plurality of cells (multi-cellular environment), the reduction of the throughput of the whole system. A base station, in the RRH system in which a plurality of antenna ports are dispersively placed in each of a plurality of cells, comprises: a selection unit that selects antenna ports, to which user terminals are to connect, from among the antenna ports of the cells in which the user terminals are existent; and a power setting unit that controls the transmission powers of the antenna ports. The selection unit and power setting unit set predetermined conditions for the target SINRs(t) of the user terminals and the transmission powers of the antenna ports, and select the antenna ports for the user terminals and control the transmission powers of the antenna ports such that the smallest one of the values of the SINRs of the user terminals of the plurality of cells is maximized.

Base station, user terminals and wireless communication method

A telecommunication control method for a heterogeneous network is provided. Uplink interference created by first user equipment (MUE) connected to a first-type cell (MeNB) is detected at the second-type cell (HeNB). The second-type cell reports the interference pattern of the detected interference to the first-type cell. The first-type cell identifies the interfering first user equipment based upon the interference pattern. The first-type cell notifies the second-type cell of the scheduling information of the interfering first user equipment. The second-type cell determines scheduling for second user equipment (HeUE) connected to the second-type cell based upon the scheduling information of the first user equipment.

Telecommunication control method, telecommunication system, and base station apparatus involving an intercell interference control technique

A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.

Two-dimensional code spreading for interleaved FDMA system

A variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) system and receiver for use therein has a sequence extension remover for removing a predetermined number of chips from the received signal to form a modified signal, and a first converter for converting the modified signal from a serial sequence to a parallel sequence. A despreader is coupled to the first converter for despreading the parallel sequence to derive a group of symbols. An orthogonal transform block, such as a Fast Fourier Transform block is coupled to the despreader to transform the symbols from the time domain to the frequency domain. An equalizer block is coupled to the transform block for equalizing the transformed signal to reduce channel distortion. A deinterleaver block is coupled to the equalizer block to form a deinterleaved signal. The deinterleaved signal is then converted from a parallel sequence to a serial sequence.

Variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) system, a receiver for use therein and a method of processing received signals in such a system

A method and apparatus for achieving combined beamforming and transmit diversity for frequency selective fading channels in a communication system having a base station with multiple transmit antennae and a mobile terminal with at least a single receive antenna, the method comprising the steps of: providing a signal to be transmitted; space-time encoding the signal to produce at least two separate signals, each on a respective output; feeding each output signal to a multiple access transmit processor to produce an output signal; applying respective selected transmit beamforming weights to each output signal; feeding the respective weighted signals to a signal combiner to perform a summing function of the signals and produce a signal for transmission; feeding the summed signal to each of the multiple transmit antennae for transmission; transmitting the signals over respective physical channels; receiving the transmitted signal at at least a single receive antenna; feeding the transmitted signal to a multiple access receive processor to produce an output signal; and space-time decoding the received signal.

Wireless communication apparatus and method

In a multi-channel communication system () data () and pilot data () are combined to provide a composite signal comprising discrete data signals (), each having a data portion () and a pilot data portion (). The composite signal is transmitted and a corresponding composite signal received on a communication channel having varying characteristics. An added pilot semi-blind (APSB) channel estimator () and equalizer () apply a converging iterative process to estimate the characteristics of the communication channel and the transmitted data.

Method and apparatus for semi-blind communication channel estimation

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.

Growing community of inventors

Singapore, Singapore

Francois Po Shin Chin