Softbank Corporation

Hapsmobile Inc.

Kenji Hoshino

Yoshichika Ota

Atsushi Nagate

Mitsukuni Konishi

Koji Tashiro

Takafumi Fujii

Shoichi Sudo

HoYu Lin

Yohei Shibata

Wataru Takabatake

In an upper-airspace staying type communication relay apparatus that performs an MU-MIMO radio communication with plural terminal apparatuses located in a cell, it is intended to improve the communication quality of the entire cell and enhance the system capacity, while suppressing an increase in overhead in the terminal apparatus and the communication relay apparatus even if the number of terminal apparatuses located in the cell increases. The communication relay apparatus receives an uplink signal from each of plural terminal apparatuses via an array antenna, estimates angle information indicating a direction of the terminal apparatus for each of the plural terminal apparatuses, selects a terminal apparatus to be assigned to each of plural radio resources used for a downlink based on the estimation result of the angle information, calculates a downlink beamforming weight based on the estimation result of the angle information, and transmits a downlink signal to the terminal apparatus via the array antenna based on the beamforming weight corresponding to the terminal apparatus and the radio resources assigned to the terminal apparatus.

Massive MIMO for HAPS based on angle information on user apparatus

Provided is an aerial-staying type communication relay apparatus that can suppress fluctuations in a directivity pattern due to reflection at an antenna-mounting member to which a service link antenna is mounted, stably fix a footprint of a cell, and as a result, prevent deterioration of communication quality. The communication relay apparatus includes an antenna having plural antenna elements that form a cell for performing a radio communication of a service link to and from the terminal apparatus and an antenna-mounting member to which the antenna is mounted, and a layer of radio wave absorber or a layer of frequency-selective electromagnetic shielding member that selectively shields radio waves having a frequency of the service link, which is provided on an outer surface exposed to an outside of the antenna-mounting member. Phases and amplitudes of signals transmitted and received via each of the plural antenna elements of the antenna may be controlled.

Suppression of reflected wave interference from antenna-mounting plate in service link of haps

An aerial-floating type communication relay apparatus (HAPS) is provided, which can perform a dynamic area control capable of coping with a change of distribution of terminal apparatuses in a service area configured with plural cells formed toward the ground, and that can suppress an increase of time required for area optimization. The aerial-staying type communication relay apparatus (HAPS) estimates positions of plural terminal apparatuses located in a service area, divides plural (L) kinds of antenna parameters of an antenna for service link into plural parameter groups, optimizes the antenna parameters based on estimation results of positions of the plural terminal apparatuses, for each of the parameter groups, and applies, to the antenna for service link, the optimum values of the plural (L) kinds of antenna parameters after completing the optimization for each of the parameter groups.

Communication relay apparatus, remote control apparatus, system, area control method and program

When there is a movement or attitude change of an upper-airspace staying type communication relay apparatus, it is suppressed of an increase in control signals and disconnection of communication with a terminal apparatus in a cell configuring a service area, and it is reduced of a circuit scale and power consumption of a base-station processing section. The base-station processing section of the communication relay apparatus performs, with respect to a radio resource part for control communication by which a communication is performed with plural terminal apparatuses located in a cell via a single or plural beams for control among downlink and uplink radio resources used for service links, a footprint fixation control for performing a precoding and a postcoding so as to fix a position of a footprint corresponding to the beam for control, based on information on at least one of a position and attitude of the communication relay apparatus, and does not perform the footprint fixation control on the basis of the information on the at least one of the position and attitude, with respect to downlink and uplink radio resource parts other than the radio resource part for control communication.

Footprint fixation control limited to specific channels considering movement and rotation of HAPS

A system and a method for suppressing a deterioration of communication quality due to frequent occurrence of handovers at cell boundaries of a plurality of cells formed by a plurality of radio relay apparatuses that can move in an upper airspace, are provided. In the system, each of the plurality of radio relay apparatuses for performing a radio communication with a terminal apparatus comprises a radio relay station which is movably provided by flying in an upper airspace, forms a cell toward the ground or the sea, and performs a radio communication with a terminal apparatus located in the cell. Each of the plurality of radio relay apparatuses flies in cooperation with each other so as to maintain a positional relationship between the radio relay apparatuses by an autonomous control or external control.

HAPS cooperative flight system

Provided is an aerial-floating type communication relay apparatus capable of reducing a size and suppressing a movement of a cell footprint. The communication relay apparatus comprises an array antenna that has plural antenna elements forming a cell for performing a radio communication of a service link with a terminal apparatus, an information acquisition section that acquires information on at least one of a position and an attitude of the communication relay apparatus, and a control section that controls phases and amplitudes of plural transmission/reception signals transmitted/received via each of the plural antenna elements of the array antenna so as to fix the position of the cell footprint, based on the information on at least one of the position and the attitude of the communication relay apparatus.

Service link antenna configuration and beam forming control in HAPS

In a mobile communication system using a mobile-type radio relay apparatus that forms a plurality of cells toward the ground or the sea while moving in an upper airspace, a deterioration in communication quality, which is caused by a Doppler shift of a reception signal due to a relative movement of a radio relay apparatus with respect to a terminal apparatus of each of a plurality of cells or a feeder station on the ground or on the sea, is suppressed. The communication system comprises a mobile-type radio relay apparatus that is disposed movably by flying in an upper airspace, forms a plurality of cells from an antenna at a predetermined altitude toward the ground or the sea, and performs a radio communication with a terminal apparatus located in each of the plurality of cells. The communication system comprises an estimation section for estimating a Doppler shift in at least one of a radio communication of a service link between the terminal apparatus located in the cell and the radio relay apparatus and a radio communication of a feeder link between the radio relay apparatus and a feeder station on the ground or on the sea, and a correction section for correcting a frequency of the at least one radio communication based on an estimation result of the Doppler shift.

Doppler shift correction in three-dimensional network

A communication system, in which a sufficient reception power can be obtained without being affected by attenuation such as rainfall in each of a radio relay apparatus and a gateway station, is provided. The communication system performs a communication via a radio relay apparatus located in an upper airspace. A plurality of gateway stations for forming feeder-link radio sections between the own gateway stations and the radio relay apparatus are disposed at a plurality of locations geographically separated from each other on the ground or on the sea. The plurality of gateway stations perform simultaneous transmissions/receptions of signals via the plurality of feeder links or transmissions/receptions of signals accompanied by a switching of the feeder links, with the radio relay apparatus.

Growing community of inventors

Tokyo, Japan

Kenji Hoshino