Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Shoji Miyamoto

Yasuaki Yuda

Takashi Fukagawa

Keiji Takakusaki

Takaaki Kishigami

Takaaki Kisigami

Keiji Takausaki

Sadaki Futagi

Atsushi Sumasu

Takao Nihei

A device for estimating a direction-of-arrival of a radio wave, the device comprising an array antenna including a plurality of antenna elements for receiving a high frequency signal, a demultiplexer for demultiplexing the received high frequency signal for each of the plurality of antenna elements to generate a plurality of frequency component signals and a direction estimating unit for estimating the direction-of-arrival of the radio wave by using two or more of the plurality of frequency component signals which are contiguous in a frequency direction.

Adaptive antenna radio communication device

A receiver having an array antenna estimates arrival directions of multiple paths that arrive with an angular spread. Consequently, arrival direction estimation accuracy can be ensured without increasing throughput even if the power every path is low by estimating an average arrival direction of an entire set of multiple paths having the angular spread from a result of one angular spectrum by multiple correlation operation units that perform mutual correlation operations with pilot signals for baseband signals received by the array antenna, a path detection unit that detects multiple arrival path receiving timings by generating a delay profile based on output of each of the correlation operation units, a path correlation value synthesis unit that synthesizes a correlation operation value calculated in the multiple correlation operation units and an arrival direction estimation unit that collectively estimates multiple path arrival directions using output of the path correlation value synthesis unit.

Radio communication device and arrival direction estimation method

An adaptive antenna radio communication device comprises a divided band direction estimating unit for estimating the direction by calculating the cross correlations between a pilot signal and sub-carrier signals of the respective divided bands received by an array antenna and calculating a spatial profile from correlation matrices determined by combining the correlation values between antenna elements of the different sub-carriers according to the output of the cross correlation calculation; a divided band array weight creating unit for creating a weight of a receive array having a directional beam in the direction of estimation for each divided band; and a sub-carrier directivity creating unit for creating a directivity by multiplication-combining the created receive array weight with the corresponding sub-carrier signal.

A transmission weight computing section computes a transmission weight for directional transmission using an OFDM signal. A transmission correcting value memory section stores one correcting value for correcting the transmission weight for each sub-carrier of an OFDM signal or each band gathering a plurality of sub-carriers. A transmission weight correcting section corrects the transmission weight by the correcting value. A transmitting branch weights transmission data by a transmission weight outputted from the transmission weight correcting section on a sub-carrier-by-sub-carrier basis and delivers it to an antenna.

Radio base station apparatus

An apparatus that can lower the possibility of failing reception modulation in communication where data is transmitted with and without directivity and prevent deterioration of transmission efficiency caused by retransmission. With this apparatus, a gain control signal multiplex section () time division multiplexes a directional transmission signal and a gain control signal. A transmission level control section () controls the transmission power level of a gain control signal so that the transmission power level of the gain control signal is smaller than the transmission power level of a directional transmission signal and the received power level of the gain control signal is larger than a received power level of a nondirectional transmission signal at the receiving side, and controls the transmission power level of a directional transmission signal so that the received power level of the directional transmission signal is larger than the received power level of a nondirectional transmission signal and the received power level of a gain control signal at the receiving side.

Transmission device and gain control method

An adaptive antenna radio communication device comprises a divided band direction estimating unit () for estimating the direction by calculating the cross correlations between a pilot signal and sub-carrier signals of the respective divided bands received by an array antenna () and calculating a spatial profile from correlation matrices determined by combining the correlation values between antenna elements of the different sub-carriers according to the output of the cross correlation calculation; a divided band array weight creating unit () for creating a weight of a receive array having a directional beam in the direction of estimation for each divided band; and a sub-carrier directivity creating unit () for creating a directivity by multiplication-combining the created receive array weight with the corresponding sub-carrier signal.

A radio communication apparatus using an array antenna has a plurality of reception branches for conveying reception signals received at the antenna element of the array antenna, and a calibration branch for selecting one of the plurality of reception branches and conveying the reception signal. Channel estimations are made respectively on the reception-branch signals and a calibration-branch signal. RAKE composition is made on the channel estimation values, a result of which is used to detect amplitude and phase deviations on the reception branch thereby carrying out a correction.

Radio communication apparatus

A path search circuit according to the present invention has an orthogonal multi-beam forming sectionfor directional reception with a plurality of orthogonal multi-beams orthogonal one to another, correlation-operating sectionsM for correlation-operating outputs of the orthogonal multi-beam forming sectionwith a known signal, weight multiplying sectionsNb for multiplying the output of the correlation-operating sectionM by a weight converted into a beam space, delay profile generating sectionsNb for generating delay profiles from the output signals of the weight multiplying sectionsNb, and a path detecting sectionfor detecting a reception timing and arrival direction of arrival path from the delay profile. This path search circuit can enhance the accuracy of path direction detection by the use of a directional reception signal, and further reduce the direction dependence of path timing detection accuracy.

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Sendai, Japan

Shoji Miyamoto