A method for positioning a set of reconfigurable intelligent surfaces associated with an access point of a telecommunications network. The set includes at least one reconfigurable intelligent surface, called an intermediate surface and at least one other reconfigurable intelligent surface, called a main surface. The method particularly includes determining positioning data of the intermediate and main surfaces such that signals emitted by the access point are reflected by the intermediate surface toward the main surface to exchange data with at least one user terminal situated in the geographical area served by the main surface, but also such that a path gain of a path taken by said signals between the access point and this user terminal is greater than a predetermined threshold or maximized.

Controller devices and control methods are provided. At the transmitting side, a data portion is obtained and a RIS is used, including a plurality of elements, to transmit the data portion. The plurality of elements are partitioned into L groups. For each group, all elements of the group are configurable in the same one of a Quadrature mode or an In-Phase mode. A pattern is selected out of a predefined set of patterns according to the data and a predefined correspondence between group patterns and respective data portions which is a subset of all possible patterns for the L groups. Each pattern in the predefined set of patterns defines for each of the L groups whether the group is configured in the Quadrature mode or in the In-phase mode. The data portion is transmitted according to the selected pattern. The corresponding demodulation is provided for the receiving side.

A data center system having plural components including core switches and racks R.sub.i, each rack R.sub.i having plural servers; a global controller configured to control a traffic flow to each rack of the plural racks R.sub.i; plural reconfigurable intelligent surface, RIS, modules, a RIS module being configured to receive a first electromagnetic signal from a first component and emit a second electromagnetic signal toward a second component, the second electromagnetic signal carrying a same information as the first electromagnetic signal; and a local controller configured to adjust an emitting direction of the second electromagnetic signal by changing a current flow through the RIS module.

A transceiver device, including a multi-antenna feeder array and a reconfigurable intelligent surface (RIS), where the multi-antenna feeder array includes a plurality of active antennas configured to transmit electromagnetic radiation based on a data stream pre-coded with a pre-coder. The RIS includes a plurality of passive antennas, each passive antenna is configured to receive the electromagnetic radiation from the multi-antenna feeder array and to re-transmit the received electromagnetic radiation with a respective adjustable phase shift. The transmission from the plurality of active antennas of the multi-antenna feeder array to the plurality of passive antennas of the RIS is defined by a transmission matrix, where the multi-antenna feeder array is configured to generate the pre-coder based on one or more generalized eigenvectors of the transmission matrix.

A method of self-configuration of a reconfigurable intelligent surface (RIS) for optimizing a gain of a reflected beam between a base station (BS) and a User Equipment (UE) includes acquiring, using power sensing capabilities of the RIS, a power profile through sequential activation of probing beams. An angular position of the BS and the UE is obtained by identifying power profile peaks in the acquired power profile. An optimal RIS configuration is computed locally according to the obtained angular position of the BS and U. The RIS is self-configured by setting the computed optimal RIS configuration.

A network side device, a first device, and a terminal device are provided. The network side device includes: a processor, a memory, and a computer program stored in the memory and capable of running on the processor. The computer program, when executed by the processor, causes the processor to perform a method for determining an operation mode. The method includes: determining first information; and determining at least a first operation mode of the first device based on the first information. The first operation mode comprises at least one of the following: a first beam direction of a reflected signal or a refracted signal of a first device; a first beamforming mode of the reflected signal or the refracted signal of the first device; or a first polarization mode of the reflected signal or the refracted signal of the first device.

This disclosure discloses a communication method and apparatus. In the method, a reflector is used to assist in communication between a terminal and an access network device, and in a reflector-assisted communication process, the reflector is indicated to be in a working mode when being required by the terminal or the access network device, to assist in communication, and the reflector is indicated to be in a sleep mode when being required by the terminal or the access network device, to reduce power consumption.

A terminal device sends T.sub.1 reference signals, where the T.sub.1 reference signals are reflected to a network device through a reconfigurable intelligent surface (RIS), T.sub.1 is a positive integer less than M, and M is a quantity of unit cells included in the RIS. The terminal device receives first information from the network device, where the first information indicates a value of T.sub.2, and T.sub.2 is a positive integer less than M. The terminal device sends T.sub.2 reference signals, where the T.sub.2 reference signals are reflected to the network device through the RIS, the T.sub.2 reference signals are used to estimate a cascaded channel, and the cascaded channel includes a channel between the network device and the RIS and a channel between the RIS and the terminal device.

There is provided mechanisms for communication between radio transceiver devices via meta-surface. A method is performed by a first radio transceiver device. The first radio transceiver device is communicating with a second radio transceiver device via at least one meta-surface over a radio propagation channel. The method comprises performing random access procedures with the second radio transceiver device. Each random access procedure corresponds to a respective activation setting of the at least one meta-surface. The method comprises selecting one of the activation settings for the at least one meta-surface. The method comprises transmitting an indication of the selected activation setting to the second radio transceiver device and a controller of the at least one meta-surface. The method comprises communicating with the second radio transceiver device over the radio propagation channel and via the at least one meta-surface.

An intelligent reflecting surface includes a first patch electrode; a second patch electrode adjacent to the first patch electrode; a third patch electrode adjacent to the first patch electrode; a fourth patch electrode adjacent to the second patch electrode and the third patch electrode; a common electrode facing the first patch electrode and the second patch electrode; a liquid crystal layer between the first patch electrode and the second patch electrode and the common electrode, and a first wiring between the first patch electrode and the second patch electrode, wherein an area of the first patch electrode is different from an area of the second patch electrode and the third patch electrode, and a distance between the first patch electrode and the first wiring is equal to a distance between the second patch electrode and the first wiring.