28 results about "Radio relay" patented technology

There is provided techniques for controlling an RIS. The RIS comprises a controller entity and a reflector entity. The reflector entity is associated with configurable reflection properties defining how radio waves that impinge the reflector entity are reflected. The reflection properties are controlled by the controller entity. A method is performed by a network node. The method comprises determining that the RIS to refrain from reflecting signals communicated in radio waves between the network node and a user equipment. The method comprises, in response thereto, providing an indication to the controller entity for the RIS to enter a non-relay mode according to which the reflector entity is to apply a default configuration of the reflection properties.

This invention provides a communication system capable of maintaining FDD communication in a base station device and a terminal device, and reducing the impact of phase noise in a relay radio section between a radio relay device and a gateway device. The radio relay device includes a means for converting an FDD signal transmitted and received in a radio section of a service link between the radio relay device and the terminal device, and a TDD signal transmitted and received in a relay radio section between the radio relay device and the gateway device. The gateway device includes a means for converting an FDD signal transmitted / received to / from the base station device, and a TDD signal transmitted / received in the relay radio section between the gateway device and the radio relay device. The radio relay device and the gateway device transmit / receive radio signals in the TDD scheme in the relay radio section.

Provided is a repeater-type radio relay system that can prevent loop interference of radio waves with the same frequency and does not require a frequency for relaying. The radio relay system is provided with one or more optical fibers for relaying an optical communication between a relay-source radio relay apparatus and a relay-destination radio relay apparatus. The relay-source radio relay apparatus has a network-side communication section for communicating with a mobile-communication network side, and an electro-optical signal conversion section of relay source for converting between an electrical signal in the mobile-communication network side received from the network-side communication section and an optical signal propagating through the optical fiber. The relay-destination radio relay apparatus has a terminal-side communication section for wirelessly communicating with the terminal apparatus side, and an electro-optical signal conversion section of relay destination for converting between an electric signal in the terminal apparatus side received from the terminal-side communication section and an optical signal propagating through the optical fiber.

A radio relay system according to one embodiment of the present invention relays a radio wave radiated by a radio communication device to a moving radio terminal, and includes: a plurality of radio wave direction change units that each change the direction of travel of a radio wave incident from the radio communication device so that the radio wave is emitted in another direction; and a control unit that controls the direction of the radio wave emitted by each of the radio wave direction change units. The control unit includes: an estimation unit that estimates a position to which the radio terminal is to move after elapse of a predetermined period of time; and a sequential allocation unit that uses the position of the radio terminal estimated by the estimation unit to determine an allocation in which each of the radio wave direction change units sequentially emits a radio wave toward the radio terminal each time the predetermined period of time elapses.

To provide a radio device capable of adaptively calculating a route cost with small fluctuation over time without needing any table.SOLUTION: A radio device includes a processing unit and a communication unit. The processing unit calculates a route cost between a first other radio device operating as a gateway terminal and an own radio device operating as a radio terminal based on the number of hops which is the number of relays of a radio signal by a second other radio device that may be interposed as a radio relay device between the first other radio device and the own radio device, and a movement cost reflecting a cumulative value of a movement state of the own radio device. The communication unit transmits first route cost information regarding the route cost to a third other radio device that is selecting a connection destination for wireless communication with the first other radio device. The processing unit calculates the movement cost at a first time based on the speed of the own radio device at the first time and the movement cost before the first time.SELECTED DRAWING: Figure 2

To provide a wireless repeater that uses the same antenna design and antenna components and is capable of responding to two or more types of orthogonal polarization, such as vertical / horizontal polarization sharing and ±45° polarization sharing.SOLUTION: A wireless repeater includes: a first antenna and a second antenna which respond to two polarizations with two different polarization surfaces; and a substrate part. The wireless repeater further includes a polarization rotation mechanism for rotating the first antenna and the second antenna by at least 45 degrees.SELECTED DRAWING: Figure 1

The present invention relates to the field of communications, and more particularly to methods and a system for providing high-speed communications on a high-speed railway. The technical result is a better quality communication channel provided by train-to-ground radio relay links. The claimed system for providing high-speed communications on a high-speed railway comprises an internal and an external data exchange network. The internal network unites tail-end radio frequency modules mounted in the rear part of a train and equipped with narrow-band antennae, head-end radio frequency modules mounted in the front part of the train and equipped with narrow-band antennae, and switching equipment capable of processing signals from said modules and of providing network devices connected to said equipment with access to the external data exchange network. The external data exchange network unites base stations equipped with narrow-band antennae, said base stations being capable of establishing communication with the tail-end and head-end radio frequency modules in the train and being arranged in proximity to the railway clearance along the path of travel of the train. The antennae of the base stations and of the radio frequency modules in the train are configured to radiate radio waves in a short millimeter wave band.

To continue continuous communication with only a small interruption without being subject to a restriction in a wireless relay system that cannot resume relay communication unless a predetermined transmission pause time is set when the relay of continuous communication exceeds a predetermined time limit. [Solution] The repeater 100 switches between two pairs of opposite waves. When relaying continuous communication on one pair of waves begins, a timer is started to measure the time limit of 3 minutes and 30 seconds before that (S217 → S222). When continuous communication exceeds 2 minutes 30 seconds, carrier sense for the other pair of waves is repeated. If a transmission stop or dead state occurs and the result of the most recent carrier sense at that time is an idle state, relaying on the currently used pair of waves is terminated and a beacon signal to switch to the other pair of waves is transmitted, causing communication terminals 201 and 202 to also set the other pair of waves to a use state (S223 to S230 → FIG. 5A). The pair of waves used is changed before the time limit, so the above restriction is not imposed.

To easily determine the antenna beam of a wireless relay device.SOLUTION: A wireless relay device receives notification of terminal beam information from a wireless terminal indicating the directional direction of the wireless terminal's antenna beam to be directed toward a base station, which has been determined between the wireless terminal and the base station, and determines the wireless relay device's antenna beam to be directed toward the base station on the basis of the directional direction indicated in the terminal beam information notified from the wireless terminal.SELECTED DRAWING: Figure 3

The wireless communication system includes a wireless relay station staying in the air, a ground station for transmitting and receiving radio waves to and from the wireless relay station, and a wireless relay station monitoring control device. The wireless relay station monitoring control device calculates a prediction value of a rainfall attenuation amount of the feeder link at a movement candidate position in a radio relay area of the wireless relay station and a current position on the basis of weather prediction information. Further, the communication quality of the feeder link at the movement candidate position and the current position is predicted based on the prediction value. Further, a position at which attenuation of the feeder link is predicted to be less than that at which the wireless relay station stays at the current position is selected from the movement candidate positions on the basis of the communication quality.

In a wireless repeating system that performs group communication using paired waves in a semi-duplex system, communication becomes impossible if there is jamming radio waves at the repeater or communication terminal. [Solution] The repeater 50 has a modulation / transmission unit TX01 for communication and a reception / demodulation unit RX01, as well as a reception / demodulation unit RX02 that cyclically scans a group of channels that are always available to search for an available pair of waves, and each communication terminal 60 has a modulation / transmission unit TX11 and a reception / demodulation unit RX11 that has the cyclic scanning function in standby mode. When jamming radio waves are detected in RX01 of the repeater 50, the RX01 changes the setting to the pair of waves that is the farthest away from a non-available pair of waves among the available pairs of waves searched for by RX02, and transmits a channel change request (CCR) from TX01. Each communication terminal 60 receives the CCR during the cyclic scanning process of RX11, and changes the setting of TX11 and RX11 to the transmission / reception pair of waves that corresponds to the receiving channel of the CCR.

It is provided of a communication system capable of suppressing a fluctuation in a reception power of a known signal from a base station due to an attitude change of a radio relay apparatus, and performing an appropriate gain control of a power amplifier of the radio relay apparatus based on the reception power of the known signal, in case that the base station uses a plurality of linear polarization antennas for wireless communication with the radio relay apparatus. The base station comprises an antenna apparatus that has a plurality of linear polarization antennas capable of transmitting and receiving radio waves with different angles of linear polarization planes from each other when performing a feeder-link communication with the radio relay apparatus, and a base-station processing section or an externally-attached phase control apparatus for controlling a phase difference between plural transmission signals supplied to the plurality of the linear polarization antennas, so that a combined polarization of radio waves of the known signal transmitted from the antenna apparatus to the radio relay apparatus becomes a circular polarization or an elliptical polarization, with respect to a predetermined time slot for transmitting to the radio relay apparatus a specific known signal usable for gain control of a power amplifier of the radio relay apparatus.

To improve a stability of an operation of a radio repeater in a TDD system radio system.SOLUTION: A radio repeater that relays a signal transmitted and received between a terminal and a base station in a TDD system radio system, comprises: a downlink received power change detection part that detects a change of a received power of a radio signal received by a base station corresponding antenna; an uplink received power change detection part that detects the change of the received power of the radio signal received by a terminal corresponding antenna; and a control part that performs switching control of a downlink direction and an uplink direction in the TDD system on the basis of a result of a detection of the change of the received power of the radio signal by the downlink received power change detection part. The control part changes the switching control on the basis of the result of the detection of the change of the received power of the radio signal by the uplink received power change detection part.SELECTED DRAWING: Figure 2

To provide a ground system, an unmanned aircraft, and a radio relay system capable of appropriately replacing the unmanned aircraft under the assumption that the radio relay system is mounted on the unmanned aircraft.SOLUTION: The ground system includes a transmission unit configured to transmit, to an unmanned aerial vehicle, a frame to be relayed by the unmanned aerial vehicle, a reception unit configured to receive, from the unmanned aerial vehicle, a signal indicating that synchronization of the frame is established in the unmanned aerial vehicle, and a control unit configured to control transmission of switching information for notifying a timing for starting or stopping relay of the frame in the unmanned aerial vehicle in accordance with the signal indicating that synchronization of the frame is established.SELECTED DRAWING: Figure 3

The invention provides a self-spatial topology distribution sensing method based on a narrowband wireless network, which is characterized in that a representative node is selected from numerous communication nodes in the network, the representative node has the functions of sending Beacon and radio transfer service, and in the algorithm, the representative node has the functions of sending Beacon and radio transfer service. Election is mainly carried out according to the proximity relation of communication nodes, connected areas or the weights of the nodes, and when the communication nodes have more than one connected area, the communication nodes can participate in election; when the communication area of the representative node is larger than one, executing a process of quitting the state; through the two functions, the normal operation of the network can be maintained only by specifying some representative nodes in numerous nodes, and the method enables the air interface overhead of the network to be less, can meet the wide area of the network, and can adaptively change the representative nodes according to the topological structure of the network.

[Problem] To provide a radio repeater capable of handling two or more kinds of orthogonal polarized waves, e.g. vertical / horizontal dual polarization or ± 45° polarization, by using the same antenna design and antenna components. [Solution] This radio repeater includes a substrate part and a first antenna and a second antenna corresponding to two polarized waves having mutually different polarization planes. The radio repeater further includes a polarization rotation mechanism that rotates the first antenna and the second antenna by 45° or more.

To improve a stability of an operation of a radio repeater in a TDD system radio system.SOLUTION: A radio repeater that relays a signal transmitted and received between a terminal and a base station in a TDD system radio system, comprises: a base station corresponding antenna that receives a downlink radio signal that is transmitted from a base station in a downlink direction directed from the base station to a terminal; a terminal corresponding antenna for receiving an uplink radio signal that is transmitted from the terminal in an uplink direction directed from the terminal to the base station; an uplink received power change detection part that detects a change of a received power of the radio signal received by the terminal corresponding antenna; and a control part that performs switching control of the downlink direction and the uplink direction in a TDD system on the basis of a result of a detection of the change of the received power of the radio signal by the uplink received power change detection part in a pairing period with the terminal.SELECTED DRAWING: Figure 2

This radio base station executes setting in a radio resource control layer with a radio relay device provided with a reflection plate, and receives a setup completion message from the radio relay device. The radio base station receives the setup completion message including identification information for identifying the radio relay device.

[PROBLEM] The purpose of the present invention is to solve the problem of a size increase by integrating two systems of system configuration into one system with an intermediate frequency band. [SOLUTION] A first unit, a second unit, and one cable connecting the first unit and the second unit are provided. The first unit comprises: a first connection part connected to an analog cable and N donor antennas which are from among a first donor antenna to an N-th donor antenna and which communicate with a base station, where N is an integer of 2 or greater; and N donor-side frequency conversion units from among a donor-side first frequency conversion unit to a donor-side N-th frequency conversion unit. Each of the N donor-side frequency conversion units from the donor-side first frequency conversion unit to the donor-side N-th frequency conversion unit converts a signal with a frequency fRF received by a corresponding donor antenna, among the N donor antennas from the first donor antenna to the N-th donor antenna, into an intermediate signal according to the respective local signal. The local signal and the intermediate signal have different frequencies for each donor-side frequency conversion unit. The second unit is provided with: a second connection part connected to an analog cable and N service antennas, from a first service antenna to an N-th service antenna, which communicate with a communication terminal; and N service-side frequency conversion units from a service-side first frequency conversion unit to a service-side N-th frequency conversion unit. Each of the N service-side frequency conversion units from the service-side first frequency conversion unit to the service-side Nth frequency conversion unit converts a signal with a frequency fRF received by a corresponding service antenna, among the N service antennas from the first service antenna to the N-th service antenna, into an intermediate signal which is an analog signal, according to the respective local signal. The local signal and the intermediate signal have different frequencies for each service-side frequency conversion unit.　The intermediate signals from a first intermediate signal to an N-th intermediate signal are transmitted multiplexed on one cable.

The invention belongs to the technical field of high-speed rail communication security, and discloses a high-speed rail communication secure transmission method based on active RIS assistance. Comprising the following steps: constructing a high-speed rail communication system comprising a base station, an active RIS, a mobile relay and an eavesdropper; establishing a channel model; defining a reflection coefficient matrix of the active RIS; deriving received signal expressions of the mobile relay and the eavesdropper; calculating the signal-to-noise ratio of the mobile relay and the eavesdropper, and solving the channel capacity of the mobile relay and the eavesdropper according to the Shannon theorem; establishing an optimization problem taking the minimum transmitting power of the base station as a target, and setting a constraint condition; the beamforming vector of the base station and the phase shift matrix of the active RIS are jointly optimized, and an optimization problem is solved through an alternating optimization algorithm so as to realize the minimization of the transmitting power of the base station; seamless coverage and stable connection in the high-speed running process of the train are ensured, and the high-reliability requirement of high-speed rail communication is met.

To provide a control device that can prevent eavesdropping / decoding of a share and set a plurality of data transfer paths in secure distributed data transfer.SOLUTION: A control device that controls a data transfer system which includes a plurality of radio relay nodes and a plurality of transmission destination nodes displays a first radio signal output value and a radio relay node of a single relay destination on a display device when there is a radio relay node of a single relay destination in a first radio wave arrival range of a radio relay node of a first relay source, displays a second radio signal output value that is smaller than the first radio signal output value and a radio relay node that exists within a second radio wave arrival range on the display device when there are a plurality of relay destination radio relay nodes in the first radio wave arrival range, and displays a third radio signal output value that is larger than the first radio signal output value and a radio relay node that exists within a third radio wave arrival range on the display device when there is not a radio relay node of a relay destination within the first radio wave arrival range.SELECTED DRAWING: Figure 1

This base station includes: an acquisition unit that acquires position information of each of a terminal and a plurality of radio relay devices; a control unit that, on the basis of the position information, selects a radio relay device to be controlled included in the plurality of radio relay devices; and a transmission unit that transmits radio waves to the selected radio relay device.

A wireless base station according to the present invention controls transmission of system information broadcast within a cell, and transmits, within the cell, system information including an information element indicating whether a wireless relay device comprising a reflector plate can be supported.

To provide a wireless relay system capable of improving the quality of downlink signals of a feeder link corresponding to remaining cells other than the suspended cells when the operation of some of a plurality of cells formed via an overhead relay station slave unit is suspended, without increasing the total feeder link transmission power of the relay station master unit. [Solution] In a non-regenerative relay wireless relay system that relays wireless communications between a base station and terminal devices located in multiple cells via a feeder link between a relay station parent unit installed in a gateway device on land or sea and a relay station child unit installed in an aircraft or floating body in the sky, the relay station parent unit has a power distribution unit that, when operation of some of the multiple cells is suspended, distributes the power of a downlink signal corresponding to a suspended cell to the power of a downlink signal corresponding to the remaining cells other than the suspended cell.

1. The name of the design product: unmanned aerial vehicle (H-shaped). 2. The use of the design product: as a remote control unmanned aerial vehicle, adopting H-shaped design, used for material delivery, equipment mounting and radio relay, etc. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.

1. The name of the design product: unmanned aerial vehicle (I type). 2. The use of the design product: as a remote control unmanned aerial vehicle, adopting I type design, used for material delivery, equipment mounting and radio relay, etc. 3. The design points of the design product: in shape. 4. The picture or photo that can best show the design points: perspective view.

1. The name of the design product: unmanned aerial vehicle (H type). 2. The use of the design product: as a remote control unmanned aerial vehicle, with H-shaped design, for material delivery, equipment mounting and radio relay, etc. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.

A radio communication node includes: a reception unit that acquires at least one of a position of a radio relay device in the sky at a transmission time or reception time of a signal by a terminal, a position of the radio relay device at a transmission time or reception time of a signal by the radio relay device, and a position of the radio relay device at a transmission time or reception time of a signal by a radio communication node; and a control unit that calculates a propagation delay of a signal transmitted and received between the terminal and the radio communication node via the radio relay device based on at least one of the three positions.