Sanyo Electric Co., Ltd.

Tottori Sanyo Electric Co., Ltd.

Toshinori Iinuma

Yoshiharu Doi

Akio Kosaka

Mitsufumi Yoshimoto

Mitsuji Hama

Masashi Iwami

Masahiro Narita

Yasunori Akatsuka

Tadayoshi Itou

Hama: Mitsuji

In an adaptive array (), fading rate of a user is measured by a fading rate measuring circuit (), and the transmit weight vector is weighted in accordance with the fading rate by a transmitting circuit (). Thus, transmission power is increased for a user of which fading rate is large, and thus transmission directivity control for such a user becomes possible.

Radio device with transmission directivity, and control method and control program for the radio device

The control unitcalculates weighting factors for one symbol out of every k symbols. During this calculation, the control unitcalculates weighting factors for respective inphase and quadrature components of the symbol stored in every I and Q buffers based on the inphase and quadrature components. The control unitalso interpolates weighting factors for the remaining k-1 symbols. During this interpolation, the control unituses the weighting factors that are currently calculated and the weighting factors that have been previously calculated and are stored in the W buffer. The calculated and interpolated weighting factors are used for forming a directivity pattern.

Adaptive array apparatus

An adaptive array apparatus includes a control unitand a plurality of radio unitsthat each have a modulator, a transmission circuit, a switch, a phase detecting unit, a reception circuit, and a demodulator. For each radio unit, the control unitcompensates a phase amount for generating a directivity pattern used for an output signal according to a difference in phase shift amounts between a transmission subsystem and a reception subsystem.

Adaptive array apparatus and compensation method for compensating a phase difference used for generating a directivity response pattern

An access control unitincludes a table showing how time slots are currently being assigned to mobile stations that are mid-communication. The access control unitjudges whether the reception signal level measured by the reception level detection unitfor each mobile station is at least equal to a threshold value. The access control unitthen changes the assignment and the table so that the mobile stations having a reception level that is at least equal to the threshold value occupy the same time slot. The access control unitreduces the transmission power during this time slot to a level that is lower than the transmission power of other time slots. By doing so, interference with the transmission waves of nearby radio base stations can be avoided.

Radio spectrum management apparatus for base stations

A radio apparatus includes an antenna (), and a transmission circuit () and a receiving circuit () sharing the antenna. The apparatus connects an output of the transmission circuit to an input of the receiving circuit in calibration for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission and receiving circuits. Then, it connects a reference signal to the input of the receiving circuit for calculating the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the receiving circuit. Based on the subtraction of the information, the quantity of phase rotation and/or the quantity of amplitude fluctuation of a signal passing through the transmission circuit is calculated. It calculates a correction value for correcting difference in quantity of phase rotation and/or quantity of amplitude fluctuation between the transmission and receiving circuits on the basis of the information. Thus, the difference in quantity of phase rotation and/or quantity of amplitude fluctuation between the transmission circuit and the receiving circuit can be corrected.

Radio device and method of calibration of antenna directivity

A diversity receiving apparatus separately weights reception signals of a plurality of reception systems using combining coefficients based on a respective amplitude component of each reception signal and combines the weighted reception signals. The diversity receiving apparatus extracts symbol sections in the combined reception signals, and generates a clock for detecting symbols. The diversity receiving apparatus includes a converting unitfor uniformly multiplying the combining coefficients if every combining coefficient is below a predetermined threshold and I component ROMs, Q component ROMs, an I component adderand a Q component adderthat combine the reception signals using the multiplied combining coefficients.

Diversity receiving apparatus that prevents judgement errors during decoding and a clock generating circuit for a diversity circuit that prevents judgement errors during decoding

An adaptive array radio base station comprises at least three antenna elements (ANT(j=1, 2, . . . , n)) and a signal processing circuit (). In calibration, the difference in a phase rotation quantity and the difference in an amplitude fluctuation quantity between a transmission circuit and a receiving circuit in each transmission system are estimated on the basis of a known signal transmitted from each transmission system and a received signal measured in each transmission system. A phase rotation quantity of a phase shifter (PS) and an amplitude fluctuation quantity of an attenuator (ATT) are set on the basis of the results of the estimation. Thus provided are a radio apparatus and a calibration method capable of calibrating transmission characteristics of the transmission circuit and the receiving circuit in a simple structure at a low cost without providing a specific measuring circuit.

Radio device and method of calibration thereof

When signals for two mobile stations PS-A and PS-B are multiplexed using path division, a clock generating unit generates a clock signal so as to delay the timing for transmitting symbols to the mobile station PS-B by 0.5 symbol periods relative to the transmission of symbols to the mobile station PS-A. If the transmission timing is adjusted in this way, a mobile station that picks up symbols which are spatially multiplexed with the signal for the present mobile station but are intended for another mobile station will not be synchronized with the symbols for the other mobile station. The mobile station will not be able to properly demodulate the symbols for the other mobile station, and so can be prevented from outputtin

Wireless base station that staggers the transmission of symbols to spatially multiplexed mobile stations by a predetermined time that is shorter than the symbol period

A wireless base station includes a determining unit, a first calculation unit and a control unit. The determining unit determines a direction in which a specified mobile station that is to be spatially-multiplexed is located. Then, the first calculating unit calculates a first parameter group, used to form a first directional pattern for each already connected mobile station that should be spatially-multiplexed with the specified mobile station. The first directional pattern is such that a null point is formed in the determined direction. After a link channel allocation has been transmitted to the specified mobile station, the control unit performs control, so that transmission is performed to each already connected mobile station by forming the corresponding first directional pattern and further by reducing transmission power uniformly in all directions.

Wireless base station using adaptive array for spatial multiplexing

An adaptive array multiplies a radio signal received in four antennas by a received weight vector thereby separating a signal from each user. On the basis of the received signal and the received weight vector, a received power measuring circuit derives radio signal strength from each terminal. A transmit weight vector control part controls a transmit weight vector in response to the receive radio signal strength, i.e., the distance between a base station and each terminal, and reduces undesired interference with another cell by adjusting transmission power.

Path division multiple access radio apparatus having directivity control based on received radio strength

A first pattern generating unit forms an adaptive array pattern using every antenna in a plurality of antennas. A second and third pattern generating unit respectively form adaptive array patterns for groups of antennas in the plurality of antennas using a different frequency for each group. A control unit switches between pattern formation by the first pattern generating unit and pattern formations by the second and third pattern generating units.

Adaptive array device

A diversity reception device which weights in proportion to the reception level and combines a plurality of reception signals, includes a phase demodulator for demodulating the phase of the reception signal, a converter to output the sine and cosine elements of the reception signal, a sine element adder to add up sine element of each reception signal, and a cosine element adder to add up cosine element of each reception signal. The converter fetches and outputs predetermined values on sine and cosine elements of the reception signal upon input of the reception signal's reception level and phase data that is sent from phase demodulator. Therefore, the present device does not require expensive electronic circuits and can be made of small digital circuits suitable for IC including a memory.

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Gifu, Japan

Toshinori Iinuma