Disclosed is a method for wireless communication for determining the position of a wireless node. The method comprises receiving a set of reference signals from a set of at least four positioning devices, wherein the positioning devices are not arranged in a single plane. A signal propagation delay of each one of the set of reference signals is determined and a position of each one of the set of positioning devices is obtained. A convex localization problem is solved for the wireless node based at least in part on the determined signal propagation delay of each one of the set of reference signals and the position of each one of the set of positioning devices. The position of the wireless node is determined based at least in part on solving of the convex localization problem.

Methods, systems, and devices for wireless communications are described. The described techniques may enable transmitting and receiving devices to increase an effective aperture size of transmitting and receiving antenna arrays, which may increase an achievable rank of spatially multiplexed communications. For example, one or both of the transmitting device and the receiving device may use a reflective component to reflect signals transmitted between the devices, which may allow for larger effective aperture sizes without increasing a physical distance between antenna elements. In some examples, the reflective component may be a static concave mirror associated with a predetermined weight vector and focal point. In some examples, the concave mirror may be a reflective intelligent surface (RIS) of reflective elements with reflective properties which may be dynamically adjusted to various weight vectors. An orientation of the RIS may be adjusted to steer a beam in various directions in space.

A reconfiguration intelligent surface device and a beamforming method thereof, the beamforming method adapted to the reconfiguration intelligent surface device is described below. A timing synchronization signal is received. A frame boundary synchronized with a radio signal transmission/reflection device is established according to the timing synchronization signal. Beam control information is received. A reflected beam is formed by reflecting a radio signal beam transmitted or reflected by the radio signal transmission/reflection device according to the beam control information based on the frame boundary synchronized with the radio signal transmission/reflection device.

Proposed are an apparatus and a method for performing beam management based on a reconfigurable intelligent surface (RIS) in a wireless communication system. An operation method of a base station (BS) in a wireless communication system includes performing a beam search using at least one base station beam through a backhaul link between the base station and a reconfigurable intelligent surface (RIS), performing the beam search using a plurality of RIS beams for each of the at least one base station beam on the backhaul link when the RIS is set to a multi-beam mode, setting the RIS to a single-beam mode on an access link when the beam search of the backhaul link is completed, and performing a beam search of the access link by fixing beam information of the backhaul link.

Methods, systems, and devices for wireless communications are described. The method includes receiving, from a network entity at a control unit associated with a reconfigurable intelligent surface, a set of multiple reference signals via a set of multiple receive beams, acquiring, via a first antenna panel associated with the control unit, a first beam of the set of multiple receive beams, acquiring, via a second antenna panel associated with the control unit, a second beam of the set of multiple receive beams, determining reflection coefficients of the reconfigurable intelligent surface for communication with the network entity based on the acquiring of the first beam and the acquiring of the second beam, and communicating via the reconfigurable intelligent surface based on the reflection coefficients of the reconfigurable intelligent surface.

Examples provide a method of operating a CED is provided, wherein the CED provides reconfigurable filters for incident signals received along one or more input spatial directions on a radio channel and transmitted as outgoing signals into one or more output spatial directions, the method comprising: configuring the CED to apply a first filter of the reconfigurable filters for a duration greater or equal than 20 ms; detecting a first received power during application of the first filter; configuring the CED to apply a second filter of the reconfigurable filters for a duration greater or equal than 20 ms.

Techniques and apparatuses are described for multiple-input multiple-output transmissions using adaptive phase-changing devices. In aspects, a base station selects one or more adaptive phase-changing devices, APDs, to use in at least one communication path for multiple-input, multiple-output, MIMO, transmissions. The base station can perform a channel characterization process for the at least one communication path using the at least one APD and at least one UE. Based on results of the channel characterization process, the base station configures the at least one APD by which to implement single user-MIMO communication with a UE or multiple user-MIMO communication with multiple UEs. By so doing, the base station may implement MIMO transmissions using APDs to communicate with the at least one UE using same time and frequency resources, which can improve spectral efficiency of a wireless network.

A reconfigurable intelligent surface (RIS) antenna includes an RIS antenna body and a bias circuit. The RIS antenna body includes a plurality of RIS antenna units. The bias circuit is electrically coupled to the RIS antenna units of the RIS antenna body. Each RIS antenna unit includes: a metal pattern, a dielectric substrate and a control unit. The metal pattern and the control unit are formed on the dielectric substrate. The metal pattern has a resonance frequency. The control unit includes at least one metal oxide resistive element. The control unit is electrically coupled to the metal pattern and the bias circuit for changing the resonance frequency of the metal pattern by adjusting a bias applied by the bias circuit.

A communication arrangement, a method for the operation thereof and a computer program including instructions causing a computer to perform the method for the operation of the communication arrangement are disclosed. The communication arrangement includes one or more digitally controllable scatterers, DCSs, an assignment circuitry and a DCS control circuitry. The assignment circuitry is configured to assign a respective base phase shift pattern to each of the one or more DCSs. The DCS control circuitry is configured to operate, during a sequence of time intervals, each DCS of the one or more DCSs to provide a respective sequence of phase shift patterns that is obtained by applying, during each time interval of the sequence of time intervals, a respective additional phase shift from a sequence of additional phase shifts for the respective DCS to the base phase shift pattern assigned to the respective DCS.

A method of a wireless device for transmitting an orthogonal frequency division multiplexing (OFDM) signal based on a reconfigurable intelligent surface (RIS) in a wireless communication system comprises determining a reflection coefficient related to the RIS, and generating the OFDM signal based on the RIS to which the determined reflection coefficient is applied.