Nippon Telegraph and Telephone Corporation

Ntt Docomo, Inc.

Denki Kogyo Company, Limited

Keizo Cho

Toshikazu Hori

Yasushi Takatori

Kentaro Nishimori

Yuki Inoue

Akira Ishii

Hiroyuki Hosono

Shinichi Mori

Kei Igarashi

Tamami Maruyama

Keisuke Sato

Kenichi Kagoshima

Takayoshi Sasaki

Ichiro Oshima

Hitoshi Itakura

Kouichi Tsunekawa

Naobumi Michishita

Fumio Kira

The present invention realizes a thin dual-polarized leaky-wave antenna which uses a CRLH (Composite Right/Left Handed) transmission line and capable of obtaining a high tilt angle in a directivity in the vertical plane while suppressing cross polarization and side lobe at a target operation frequency. Specifically, the present invention provides a leaky-wave antenna including a dielectric substrate, a ground surface formed on a bottom surface of the dielectric substrate, a ground unit formed on a top surface of the dielectric substrate, and a CRLH (Composite Right/Left Handed) transmission line which is arranged adjacent to the ground unit and formed on a top surface of the dielectric substrate and uses a coplanar transmission line with a ground, in which a series capacitor (C) and a parallel inductor (L) constituting the CRLH transmission line are formed on a top surface of the dielectric substrate.

Leaky-wave antenna

An antenna equipment includes an array antenna including a plurality of antenna elements configured to be grouped into at least one group according to each of N communication types, where N is an integer greater than or equal to 2, a selecting part selecting one of the N communication types, a transmitting part modulating outgoing data to generate an outgoing signal for antenna element or antenna elements belonging to each group for the selected communication type, and a receiving part demodulating an incoming signal from antenna element or antenna elements belonging to each group for the selected communication type to generate incoming data.

Antenna equipment including the grouping of antenna elements according to communication types

A disclosed base station includes a communication unit configured to receive from a mobile station a first report signal including base station specification information specifying a base station, reception quality information indicating reception quality of a signal received from the specified base station, and change request information requesting to change communication quality between the mobile station and the specified base station; and an automatic area control unit configured to determine whether the base station is specified by the base station specification information, to obtain location information indicating the location of the mobile station if the base station is specified by the base station specification information, and to change at least one base station parameter based on the reception quality information and the location information to change the reception quality at the location of the mobile station.

Mobile station, base station, and area shaping method performed by specified base station

A disclosed base station apparatus for a mobile communication system includes a collection unit collecting measured data from one or more user equipment terminals with respect to each direction of arrival, the measured data including at least quality information of a downlink signal, a conversion unit converting the measured data into an evaluation value in accordance with a predetermined evaluation function, a deriving unit deriving a weight update amount determining directivity based on an angular distribution of the plural evaluation values, and a transmission unit transmitting a downlink signal weighted based on the weight update amount.

Base station apparatus and directivity control method in mobile communication system

An adaptive antenna control method is used for a radio communication system built by a plurality of radio base stations and a plurality of terminal stations capable of communicating with the radio base stations. Each radio base station includes an adaptive antenna having a plurality of antenna elements, a distributor for generating signals to be input to the plurality of antenna elements by branching a signal of one system to be transmitted, and weighting circuits for respectively weighting transmission signals to the plurality of antenna elements. For reception by each terminal station, an interference wave power given by the transmission signal from each of the plurality of radio base stations is estimated. A weight in the adaptive antenna of each radio base station is determined to minimize a sum of square errors between reception signals and desired signals for all the radio base stations which simultaneously use the same communication channel. An adaptive antenna transmission/reception characteristic control method is also disclosed.

Adaptive antenna control method and adaptive antenna transmission/reception characteristic control method

An antenna optimum design method according to this invention includes the steps of generating blocks by dividing a metal patch on an antenna element plane vertically and horizontally; setting reference point blocks in alternate blocks and assigning chromosomes to the reference point blocks; determining ways to arrange metal patches in blocks contiguous on one side to the reference point blocks, based on the chromosomes assigned to the reference point blocks; and searching for an optimum chromosomes to be assigned to the reference point blocks by a genetic algorithm to optimize antenna characteristics.

Maze creating method, antenna optimum designing method, program, and antenna, using two-bit/quaternary chromosomes

In an array antenna used in a transceiver in a time division communication system such as TDD (Time Division Duplex) system, amplitude and phase of each antenna element are calibrated in a transceiver itself during actual communication without using external information. A first transmitter ( - - ) has means ( - - ) to send a transmit signal to an antenna element ( - - ) as well as to at least one of the receivers ( - - through - -N). Other transmitter ( - - through - -k) except the first transmitter has means ( - -k) which sends a transmit signal to a related antenna element ( - - through - -k) as well as to a first receiver ( - - ) which relates to the first transmitter. Amplitude/phase value obtained in the first receiver ( - - ) and amplitude/phase values obtained in other receivers ( - - through - -k) except the first receiver provide weighted amplitude/phase values of each antenna elements according to desired desired radiation pattern.

Adaptive array antenna system

An adaptive array antenna transceiver apparatus provides: a local signal generator that outputs a signal having a frequency that corresponds to the difference between the reception frequency and the transmitting frequency; a coupler that separates and extracts a part of the signals from the output of the transmitters a switch that selects the signal output from any one of the transmitters a frequency converter that converts the frequency of the signal selected by the switch and a switch that inputs signals output by the frequency converter and selectively outputs them to any one of the plurality of paths. The transceiver further provides a switch that selectively inputs a reception signal from a said antenna elements or a signal from said second switch into each of said receivers; and a calibration control processor that controls the connection state of said switches inputs the amplitude and phase values obtained at the receivers and finds the calibration value of each of the branches of the array antenna.

Adaptive array antenna transceiver apparatus

An adaptive array antenna system for stable directivity control and waveform equalization even under poor multipath environment is provided. An output of antenna elements (A,-A,n) is weight combined (A,), and is output through automatic frequency control (A,) and fractionally spaced adaptive transversal filter (A,) which have real number weights. Weight combination (A,) is initially carried out with weights for an eigen vector beam for the maximum eigen vector of the correlation matrix R,of a receive signal After carrier synchronization and timing synchronization between a receive signal, and an A/D converter and a fractionally spaced transversal filter are established by the automatic frequency control and the fractionally spaced transversal filter, the weight in the weight combiner (A,) is switched to minimum mean square error (MMSE) weight. Sampling rate for A/D conversion under an eigen vector beam forming is higher than twice of that of transmission rate, with asynchronous timing to a receive signal.

A bidirectional printed antenna includes a dielectric substrate (33) having first and second surfaces which are substantially in parallel, at least one pair of radiation element conductors (31, 32) having the same shape and the same size, each pair of which is arranged on the first and second surfaces at positions opposing with each other, respectively, a feeding circuit (34, 35, 36, 37) coupled to at least one edge of each of the radiation element conductors, and a ground conductor (37) arranged on the second surface. The ground conductor (37) covers at least an area outside of the edge of the radiation element conductor, which edge is coupled to the feeding circuit, and an area outside of the opposite edge with respect to the radiation element conductor by leaving a gap of a predetermined width between the radiation element conductor and this ground conductor. The antenna further includes a first strip conductor (34, 35) arranged on the first surface and connected to the radiation element conductor (31) on the first surface, and a second strip conductor (36) arranged on the second surface, for connecting the radiation element conductor (32) on the second surface with the ground conductor. The above-mentioned feeding circuit includes an unbalanced feed line which consists of the ground conductor (37) and the first strip conductor (35), and a balanced feed line which consists of the first and second strip conductors (34, 36).

Bidirectional printed antenna

A pair of bands are each secured at one end to one side of a case wherein a radio receiver is housed, and a monopole antenna having a length of 0.005.lambda. has one end connected to the feeding point of the radio receiver and its other end exposed to the outside of the case to form a contact portion for contact with the human body. A first helical antenna is supported to the one of the bands lengthwise thereof and is connected at one end to the feeding point. A second helical antenna is supported to the other band lengthwise thereof and is connected at one end to the common potential point of the radio receiver. The first and second helical antennas resonate, as one antenna, with the wavelength .lambda. used by the radio receiver, and their pitch P and helix area A are selected so that P&lt;500A/.lambda. and P&gt;150A/.lambda.. In an alternative embodiment first and second zigzag antennas are supported on said pair of bands respectively, and similarly connected to said feeding and common potential points instead of said helical antennas.

Growing community of inventors

Yokohama, Japan

Keizo Cho