CONNECTION SETUP IN OAM-BASED COMMUNICATION SYSTEM

Methods, systems, and devices for connection setup in an orbital angular momentum (OAM)-based communication system are described. A first device and a second device may establish an OAM communications connection between the devices. The first device and the second device may exchange a series of messages over a downlink communications link and an uplink communications link according to an OAM mode. Based on OAM related parameters or OAM related information included in the messages, the first device and the second device may achieve a successful directional alignment (co-axial alignment) between the first device and the second device. The first device and the second device may determine one or more orbital angular momentum modes for communication between the first device and the second device based on the establishing the directional alignment.

FIELD OF TECHNOLOGY

The following relates to wireless communications, including connection setup in orbital angular momentum (OAM)-based communication systems.

BACKGROUND

A wireless multiple-access communications system may include a number of network entities or network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE). In some systems, such as in orbital angular momentum (OAM)-capable communications systems, wireless devices such as UEs and network entities may communicate using OAM beams.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support connection setup in orbital angular momentum (OAM)-based communication systems. Generally, the described techniques provide for establishing an OAM-based communications connection between a transmitting device and a receiving device.

A method for wireless communication at a first device is described. The method may include transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device, receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device, transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, transmitting the signal to the second device based on the second positional information, and receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

An apparatus for wireless communication at a first device is described. The apparatus may include a memory, a transceiver, and at least one processor of a user equipment (UE), the at least one processor coupled with the memory and the transceiver. The at least one processor may be configured to cause the apparatus to transmit a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device, receive, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device, transmit, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, transmit the signal to the second device based on the second positional information, and receive, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

Another apparatus for wireless communication at a first device is described. The apparatus may include means for transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device, means for receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device, means for transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, means for transmitting the signal to the second device based on the second positional information, and means for receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

A non-transitory computer-readable medium storing code for wireless communication at a first device is described. The code may include instructions executable by a processor to transmit a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device, receive, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device, transmit, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, transmit the signal to the second device based on the second positional information, and receive, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first message further includes a first set of orbital angular momentum parameters associated with transmissions by the first device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a list of candidate orbital angular momentum modes associated with the transmissions by the first device, a quantity of downlink transmitter circles associated with the first device, a radius associated with each of the downlink transmitter circles, a quantity of antenna elements associated with each of the downlink transmitter circles, a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink transmitter circles, a quantity of uplink receiver circles associated with reception of the transmissions by the first device, a radius associated with each of the uplink receiver circles, a quantity of antenna elements associated with each of the uplink receiver circles, and a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink receiver circles.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the second message includes a second set of orbital angular momentum parameters associated with transmissions by the second device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a list of candidate orbital angular momentum modes associated with the transmissions by the second device, a quantity of uplink transmitter circles associated with the second device, a radius associated with each of the uplink transmitter circles, a quantity of antenna elements associated with each of the uplink transmitter circles, a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink transmitter circles, a quantity of downlink receiver circles associated with the first device, a radius associated with each of the downlink receiver circles, a quantity of antenna elements associated with each of the downlink receiver circles, and a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink receiver circles.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the directional alignment information includes steering information associated with the signal, the steering information including a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the fourth message further includes an indication of a successful alignment between the first device and the second device and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for communicating one or more data transmissions with the second device according to a set of orbital angular momentum modes based on the successful alignment.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, communicating the one or more data transmissions may include operations, features, means, or instructions for transmitting, via the first orbital angular momentum mode, a configuration message associated with one or more downlink channel transmissions, the configuration message indicating a set of configured orbital angular momentum modes for the one or more downlink channel transmissions, where the set of configured orbital angular momentum modes includes two or more orbital angular momentum modes of the set of orbital angular momentum modes.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for identifying a set of parameters associated with transmitting the first message, the set of parameters including a periodicity associated with transmitting the first message.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first message indicates a set of resources allocated for receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a configuration indicating a set of resources allocated for transmitting the first message, receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for monitoring for a wake-up signal over a set of resources allocated for the wake-up signal, where the monitoring may be via the first orbital angular momentum mode and receiving the wake-up signal based on the monitoring, where transmitting the first message may be based on receiving the wake-up signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes an optical signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes a radio signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes a directional signal associated with one or more beams.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes an omnidirectional signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first orbital angular momentum mode includes orbital angular momentum mode.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting the first message, the third message, or both includes using a center radiator of one or more transmitter circles of the first device or one or more uniform circular array radiators of the one or more transmitter circles of the first device.

A method for wireless communication at a second device is described. The method may include receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device, transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device, receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, receiving the signal from the first device based on the second positional information, and transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

An apparatus for wireless communication at a second device is described. The apparatus may include a memory, a transceiver, and at least one processor of a network entity, the at least one processor coupled with the memory and the transceiver. The at least one process may be configured to cause the apparatus to receive a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device, transmit, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device, receive, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, receive the signal from the first device based on the second positional information, and transmit, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

Another apparatus for wireless communication at a second device is described. The apparatus may include means for receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device, means for transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device, means for receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, means for receiving the signal from the first device based on the second positional information, and means for transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

A non-transitory computer-readable medium storing code for wireless communication at a second device is described. The code may include instructions executable by a processor to receive a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device, transmit, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device, receive, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal, receive the signal from the first device based on the second positional information, and transmit, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first message further includes a first set of orbital angular momentum parameters associated with transmissions by the first device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes an optical signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes a radio signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes a directional signal associated with one or more beams.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the signal includes an omnidirectional signal.

DETAILED DESCRIPTION

In some wireless communications systems, wireless devices, such as network entities or user equipment (UEs), or both, may communicate directionally, for example, using beams to orient communication signals over one or more directions. In some systems, such as in orbital angular momentum (OAM)-capable communications systems, the wireless devices may communicate using OAM signals (e.g., beams), which, in addition to providing signal directionality, may also provide an additional dimension for signal or channel multiplexing. In some aspects, for example, such additional dimensions may include a state or a mode of the OAM signal, where different states or modes of OAM signals may be orthogonal to each other. As such, different OAM states or modes may be multiplexed together (also referred to herein as OAM multiplexing) to increase the capacity of an OAM link. In some cases, a wireless device may use spiral phase plate (SPP) or uniform circular array (UCA) based methodologies to generate an OAM beam. Additionally, another additional dimension may include polarization. Since any OAM mode can be one of two polarizations (e.g., two linear polarizations (e.g., one horizontal and one vertical) or two circular and elliptical polarizations (e.g., clockwise and counter-clockwise)), polarization and OAM mode may be two independent properties of electromagnetic waves and two independent sources of degrees of freedom. In some cases, using a combination of different polarizations and multiple OAM modes may support an increased number (e.g., double) of data streams in OAM-based communications in MIMO compared to OAM-based communications that do not exploit polarization.

In some cases, a transmitting device and a receiving device may each be equipped with one or more antenna circles (e.g., uniform circular arrays (UCA)) that may allow the transmitting device and the receiving device to communicate according to one or more OAM modes. In an OAM-based communication system in which a transmitting device, or a receiving device, or both are each equipped with multiple antenna circles, the efficiency of each antenna circle (e.g., channel gains of each antenna circle) may be different for each OAM mode. For example, a signal produced by a first antenna circle according to a first OAM mode may have a different channel gain than a signal produced by a second antenna circle according to the first OAM mode. To increase efficiency and throughput in the OAM-communications system, a transmitting device (e.g., a user equipment (UE), network entity, integrated access and backhaul (IAB) node, relay node, etc.) or a receiving device (e.g., a UE, network entity, IAB node, relay node, etc.), or both may determine a transmission scheme for the transmitting device to use for transmitting messages (e.g., data messages, control messages) to the receiving device. For example, the transmitting device, or the receiving device, or both may be configured to determine which antenna circle of the transmitting device (e.g., transmitter circle) to use for each OAM mode so as to optimize data throughput of each OAM mode.

In some cases, a transmitting device and a receiving device may fail to identify respective axial directions of the other device. For example, the transmitting device may fail to identify an axial direction of an antenna circle (e.g., UCA) of the receiving device. In some examples, the receiving device may fail to identify an axial direction of an antenna circle (e.g., UCA) of the transmitting device.

Accordingly, during some initial connection setup procedures for establishing a connection between the transmitting device and receiving device, a transmitting device and a receiving device may be unable to exchange information and context with respect to respective axial directions. In some cases, without the exchange of such information and context, the transmitting device and the receiving device may be unable to obtain or maintain co-axiality between the devices. In an example, the devices may thereby be unable to obtain or maintain inter-mode orthogonality among signals of different OAM modes. In some cases, without co-axiality between the devices, utilizing spatial multiplexing via multiple OAM modes may be impacted by severe mutual interference (e.g., mutual interference above a threshold).

Further, OAM modes may each have a respective channel gain determined by system parameters such as communication distance between the devices, respective radii of transmitter circles or receiver circles of the devices, and carrier wavelengths. In some OAM-based communications systems, the transmitting device and the receiving device may fail to identify such parameters, and therefore may select an OAM mode for communication between the devices that is less efficient or less optimal (e.g., according to a metric) than at least one other OAM mode.

According to example aspects of the present disclosure, a first device and a second device may establish an OAM communications connection between the first device and the second device. For example, the first device and the second device may exchange a series of messages (e.g., four messages) over a communications link (e.g., an uplink communications link, a downlink communications link) according to an OAM mode (e.g., OAM mode 0). Based on OAM related parameters or OAM related information included in the messages, the first device and the second device may achieve a successful directional alignment (co-axial alignment) between the first device and the second device. The first device and the second device may determine one or more orbital angular momentum modes (e.g., orbital angular momentum mode 1, 2, etc.) for communication between the first device and the second device based on the establishing the directional alignment.

Aspects of the disclosure are initially described in the context of a wireless communications system. Examples of processes and signaling exchanges that support connection setup in an OAM-based communications system are then described. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to connection setup in an OAM-based communications system.

In some wireless communications systems, such as wireless communications systems100, a first device, such as a transmitting device, and a second device, such as a receiving device, may each be equipped with one or more antenna circles (e.g., UCAs) that may allow the first device and the second device to communicate according to one or more OAM modes over one or more antenna circles. In some aspects, the first device may be a UE115, network entity105, integrated access and backhaul (IAB) node, relay node, etc., and the second device may be a UE115, network entity105, IAB node, relay node, etc.

According to example aspects of the present disclosure, the first device and the second device may establish an OAM communications connection between the first device and the second device. For example, the first device and the second device may exchange a series of messages (e.g., four messages) over a communications link (e.g., an uplink communications link) and another communications link (e.g., a downlink communications link) according to an OAM mode (e.g., OAM mode 0). Based on OAM related parameters or OAM related information included in the messages, the first device and the second device may achieve a successful directional alignment (co-axial alignment) between the first device and the second device. The first device and the second device may determine one or more OAM modes (e.g., OAM mode 1, 2, etc.) for communication between the first device and the second device based on the establishing the directional alignment.

For example, the first device may transmit a first message to the second device via an OAM mode (e.g., OAM mode 0). The first message may be, for example, a system information and synchronization message. In an example, the first device may transmit the first message to the second device via a communications link (e.g., a downlink communications link). In some examples, the first device may transmit the first message to the second device in response to receiving a wake-up signal from the second device. In some other examples, the first device may transmit the first message periodically (e.g., according to a set of parameters including a periodicity).

In some aspects, the first message may include a synchronization signal. In some other aspects, the first message may include first positional information (e.g., global positioning system (GPS) positioning information, a global navigation satellite system (GNSS) positioning information) associated with a first OAM circle center associated with the first device. In some examples, the first message may include a list of OAM parameters (e.g., including candidate OAM modes) associated with transmissions (e.g., downlink transmissions) by the first device.

The first device may receive a second message from the second device, via the OAM mode (e.g., OAM mode 0). The second message may be, for example, a connection request message. In some aspects, the second device may transmit (and the first device may receive) the second message in response to the first message. In an example, the second device may transmit the second message to the first device via another communications link (e.g., an uplink communications link).

In some aspects, the second message may include second positional information (e.g., GPS positioning information, GNSS positioning information) associated with an OAM circle center associated with the second device. In some other aspects, the second message may include a list of OAM parameters (e.g., including candidate OAM modes) associated with transmissions (e.g., uplink transmissions) by the second device. In some aspects, the candidate OAM modes indicated in the second message may include a subset of the candidate OAM modes indicated in the first message.

The first device may transmit a third message to the second device based on the second message. The third message may be, for example, a directional alignment request message. In some aspects, the third message may include directional alignment information associated with transmitting a signal (e.g., an optical signal, a radio signal, a directional signal associated with one or more beams, an omnidirectional signal). In an example, the directional alignment information may include steering information associated with the signal. In some examples, the steering information may include a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

Based on the second positional information of the second device, the first device may transmit the signal to the second device. In some aspects, based on the first positional information associated with a first OAM circle center associated with the first device (e.g., as included in the first message) and the directional alignment information (e.g., as included in the third message), the second device may attempt to align the second OAM circle center associated with the second device with the first OAM circle center associated with the first device. In an example, the second device may rotate the axial direction of OAM circles of the second device towards the position of the first device.

The second device may transmit (and the first device may receive) a fourth message indicating whether the signal was successfully received by the second device. The fourth message may be, for example, a directional alignment response message. In some aspects, the fourth message may include an indication of successful alignment between the first device and the second device. In some examples, the fourth message may include an indication of an unsuccessful alignment between the first device and the second device.

In some aspects, based on a successful alignment between the first device and the second device, the first device and the second device may communicate (e.g., transmit and receive) signaling messages and data transmissions according to a set of OAM modes. For example, the first device may transmit, via the OAM mode (e.g., OAM mode 0) used for communicating the first message through the fourth message, a configuration message (e.g., a physical downlink shared channel (PDSCH) configuration message) for one or more downlink channel transmissions (e.g., PDSCH transmissions). In some aspects, the configuration message (e.g., PDSCH configuration message) may indicate a set of configured OAM modes (e.g., multiple OAM modes) for the one or more downlink channel transmissions (e.g., PDSCH transmissions).

FIG.2illustrates an example of a wireless communications system200that supports connection setup in an OAM-based communication system in accordance with aspects of the present disclosure. In some examples, wireless communications system200may implement aspects of wireless communications system100. The wireless communications system200may illustrate communication between a first device205-aand a second device210-a, where the first device205-aand the second device210-amay be the same type of device or may be different types of devices. The first device205-aand the second device210-amay each be a UE, a network entity, an IAB node, etc. The first device205-aand the second device210-amay be examples of corresponding devices described herein.

In some cases, the first device205-aor the second device210-amay serve geographic coverage area110-a. In some examples, the wireless communications system200(which may be an example of a sixth generation (6G) system, a fifth generation (5G) system, or other generation of system) may support OAM-based communications. The first device205-aand the second device210-amay transmit or receive OAM beams, or OAM-related signals over communications links225within a geographic coverage area110-a.

For example, the first device205-aor the second device210-amay support OAM-based communication by using the OAM of electromagnetic waves to distinguish between different signals. The OAM of electromagnetic waves may be different than the spin angular momentum (SAM) of electromagnetic waves, and both may contribute to the overall angular momentum of an electromagnetic wave as defined in quantum mechanics by Equation 1, shown below.

As shown in Equation 1, J is equal to the angular momentum of the electromagnetic wave, r is a position vector, S=E×H and is equal to the Poynting flux, where E is equal to the electric field vector and H is equal to the magnetic field's auxiliary field vector, Σ is equal to the SAM of the electromagnetic wave (and is sometimes alternatively denoted as S), and L is equal to the OAM of the electromagnetic wave. In some cases, the SAM of the electromagnetic wave may be associated with the polarization of the electromagnetic wave. For example, an electromagnetic wave may be associated with different polarizations (e.g., circular polarizations), such as left and right. Accordingly, the SAM of the electromagnetic wave may have multiple (e.g., two) degrees of freedom.

In some cases, the OAM of the electromagnetic wave may be associated with a field spatial distribution of the electromagnetic wave, which may be in the form of a helical or twisted wavefront shape (e.g., in examples in which a light beam can be associated with a helical or twisted wavefront). For example, an electromagnetic wave (e.g., a light beam, an optical beam, a radio signal, a directional beam, an omnidirectional signal) may be in a helical mode (which may also be referred to as an OAM mode) and such helical modes may be characterized by a wavefront that is shaped as a helix with an optical vortex in the center (e.g., at the beam axis), where each helical mode is associated with a different helical wavefront structure. The helical modes (e.g., OAM modes, which may also be referred to as OAM states) may be defined or referred to by a mode index l, where a sign of the mode index l corresponds to a “handedness” (e.g., left or right) of the helix (or helices) and a magnitude of the mode index l (e.g., |l|) corresponds to a quantity of distinct but interleaved helices of the electromagnetic wave.

For example, for an electromagnetic wave associated with an OAM mode index of l=0, the electromagnetic wave is not helical and the wavefronts of the electromagnetic wave are multiple disconnected surfaces (e.g., the electromagnetic wave is a sequence of parallel planes). For an electromagnetic wave associated with an OAM mode index of l=+1, the electromagnetic wave may propagate in a right-handed sense (e.g., has a right circular polarization or may be understood as having a clockwise circular polarization) and the wavefront of the electromagnetic wave may be shaped as a single helical surface with a step length equal to a wavelength A of the electromagnetic wave. Likewise, the phase delay over one revolution of the electromagnetic wave may be equal to 2π. Similarly, for an OAM mode index of l=−1, the electromagnetic wave may propagate in a left-handed sense (e.g., has a left circular polarization or may be understood as having a counter-clockwise circular polarization) and the wavefront of the electromagnetic wave may be also be shaped as a single helical surface with a step length equal to the wavelength A of the electromagnetic wave. Likewise, the phase delay over one revolution of the electromagnetic wave may be equal to −2π.

For further example, for an OAM mode index of l=±2, the electromagnetic wave may propagate in either a right-handed sense (if +2) or in a left-handed sense (if −2) and the wavefront of the electromagnetic wave may include two distinct but interleaved helical surfaces. In such examples, the step length of each helical surface may be equal to λ/2. Likewise, the phase delay over one revolution of the electromagnetic wave may be equal to ±4π. In general terms, a mode-l electromagnetic wave may propagate in either a right-handed sense or a left-handed sense (depending on the sign of l) and may include l distinct but interleaved helical surfaces with a step length of each helical surface equal to λ/|l|. Likewise, the phase delay over one revolution of the electromagnetic wave may be equal to 2π. In some examples, an electromagnetic wave may be indefinitely extended to provide for an infinite number of degrees of freedom of the OAM of the electromagnetic wave (e.g., l=−∞, . . . , −2, −1, 0, +1, +2, . . . , +∞). As such, the OAM of the electromagnetic wave (e.g., L as defined in Equation 1) may be associated with infinite degrees of freedom.

In some examples, the OAM mode index l of an electromagnetic wave may correspond to or otherwise function as (e.g., be defined as) an additional dimension for signal or channel multiplexing. For example, each OAM mode or state (of which there may be infinite), may function similarly (e.g., or equivalently) to a communication channel, such as a sub-channel. In other words, an OAM mode or state may correspond to a communication channel, and vice versa. For instance, the first device205-aor the second device210-amay communicate separate signals using electromagnetic waves having different OAM modes or states similarly to how the first device205-aor the second device210-amay transmit separate signals over different communication channels. In some aspects, such use of the OAM modes or states of an electromagnetic wave to carry different signals may be referred to as the use of OAM beams.

Additionally, in some examples, electromagnetic waves with different OAM modes (e.g., OAM states) may be mutually orthogonal to each other (e.g., in a Hilbert sense, in which a space may include an infinite set of axes and sequences may become infinite by way of always having another coordinate direction in which next elements of the sequence can go). Likewise, in a Hilbert sense, orthogonal OAM modes or states may correspond to orthogonal communication channels (e.g., orthogonal sequences transmitted over a communication channel) and, based on the potentially infinite number of OAM modes or states, the wireless communications system200employing the use of OAM beams may theoretically achieve infinite capacity. For example, in theory, an infinite number of OAM states or modes may be twisted together for multiplexing and the capacity of the OAM link can approach infinity while preserving orthogonality between signals carried by different OAM modes (e.g., indices). In practice, however, due to non-ideal factors (e.g., Tx/Rx axial or position placement error, propagation divergence, and the like), crosstalk among OAM modes at the receiver may result, and thus a reduced number of concurrent OAM modes may be implemented between wireless devices (e.g., two or four concurrent OAM modes). In some cases, the first device205-aor the second device210-amay generate such OAM beams using SPP or UCA methodologies, such as discussed with reference toFIGS.3and4.

In some aspects, an as described with respect toFIG.4, the first device205-a, or the second device210-a, or both may be configured with a set of antennas configured in a circle, such as a UCA antenna circle (e.g., antenna circle, transmitter circle). In some cases, the first device205-aand the second device210-amay each be equipped with one or more UCA circles that the first device205-aand the second device210-amay use to communicate according to one or more OAM modes. In scenarios in which the first device205-a, or the second device210-a, or both each are equipped with multiple UCA circles, the efficiency of each UCA circle (e.g., the channel gain of signals from each UCA circle) may be different for each OAM mode. For example, a signal produced by a first antenna circle according to a first OAM mode may have a different channel gain than a signal produced by a second antenna circle according to the first OAM mode. In some aspects, a transmitting device (e.g., the first device205-a, the second device210-a) may radiate multiple coaxially propagating, spatially-overlapping waves (OAM mode l=−∞, . . . , −2, −1, 0, +1, +2, . . . , +∞) each carrying a data stream through a pair of apertures or an array of apertures.

According to example aspects of the present disclosure, the first device205-aand the second device210-amay establish an OAM communications connection between the first device205-aand the second device210-a. For example, the first device205-aand the second device210-amay exchange a series of messages (e.g., four messages) over a communications link225-a(e.g., an uplink communications link) and a communications link225-b(e.g., a downlink communications link) according to an OAM mode (e.g., OAM mode 0). Based on OAM related parameters or OAM related information included in the messages, the first device205-aand the second device210-amay achieve a successful directional alignment (co-axial alignment) between the first device205-aand the second device210-a. The first device205-aand the second device210-amay determine one or more OAM modes (e.g., OAM mode 1, 2, etc.) for communication between the first device205-aand the second device210-abased on the establishing the directional alignment.

For example, the first device205-amay transmit a first message215to the second device210-avia an OAM mode (e.g., OAM mode 0). The first message215may be, for example, a system information and synchronization message. In an example, the first device205-amay transmit the first message215to the second device210-avia communications link225-b(e.g., a downlink communications link). In some examples, the first device205-amay transmit the first message215to the second device210-ain response to receiving a wake-up signal from the second device210-a. In some other examples, the first device205-amay transmit the first message215periodically (e.g., according to a set of parameters including a periodicity).

In some aspects, the first message215may include a synchronization signal. In some other aspects, the first message215may include first positional information (e.g., GPS positioning information, GNSS positioning information) associated with a first OAM circle center associated with the first device205-a. In some examples, the first message215may include a list of OAM parameters (e.g., including candidate OAM modes) associated with transmissions (e.g., downlink transmissions) by the first device205-a.

The first device205-amay receive a second message220from the second device210-a, via the OAM mode (e.g., OAM mode 0). The second message220may be, for example, a connection request message. In some aspects, the second device210-amay transmit (and the first device205-amay receive) the second message220in response to the first message215. In an example, the second device210-amay transmit the second message220to the first device205-avia communications link225-a(e.g., an uplink communications link).

In some aspects, the second message220may include second positional information (e.g., GPS positioning information, GNSS positioning information) associated with an OAM circle center associated with the second device210-a. In some other aspects, the second message220may include a list of OAM parameters (e.g., including candidate OAM modes) associated with transmissions (e.g., uplink transmissions) by the second device210-a. In some aspects, the candidate OAM modes indicated in the second message220may include a subset of the candidate OAM modes indicated in the first message215.

The first device205-amay transmit a third message230to the second device210-abased on the second message220. The third message230may be, for example, a directional alignment request message. In some aspects, the third message230may include directional alignment information associated with transmitting a signal (e.g., an optical beam, a radio signal, a directional signal associated with one or more beams, an omnidirectional signal). In an example, the directional alignment information may include steering information associated with the signal. In some examples, the steering information may include a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

Based on the second positional information of the second device210-a, the first device205-amay transmit the signal to the second device210-a. In some aspects, based on the first positional information associated with a first OAM circle center associated with the first device205-a(e.g., as included in the first message215) and the directional alignment information (e.g., as included in the third message230), the second device210-amay attempt to align the second OAM circle center associated with the second device210-awith the first OAM circle center associated with the first device205-a. In an example, the second device210-amay rotate the axial direction of OAM circles of the second device210-atowards the position of the first device205-a.

The second device210-amay transmit (and the first device205-amay receive) a fourth message235indicating whether the signal was successfully received by the second device210-a. The fourth message235may be, for example, a directional alignment response message. In some aspects, the fourth message235may include an indication of successful alignment between the first device205-aand the second device210-a. In some examples, the fourth message235may include an indication of an unsuccessful alignment between the first device205-aand the second device210-a.

In some aspects, based on a successful alignment between the first device205-aand the second device210-a, the first device205-aand the second device210-amay communicate (e.g., transmit and receive) signaling messages and data transmissions according to a set of OAM modes. For example, the first device205-amay transmit, via the OAM mode (e.g., OAM mode 0) used for communicating the first message215through the fourth message235, a configuration message (e.g., a PDSCH configuration message) for one or more downlink channel transmissions (e.g., PDSCH transmissions). In some aspects, the configuration message (e.g., PDSCH configuration message) may indicate a set of configured OAM modes (e.g., multiple OAM modes) for the one or more downlink channel transmissions (e.g., PDSCH transmissions).

Examples of aspects of the message exchanges between the first device and the second device and contents of the messages are described herein, for instance with reference toFIGS.6and7.

Although the present example describes first device205-atransmitting the first message215and the third message230and second device210-atransmitting the second message220and the fourth message235there may be examples where first device205-atransmits the first message215and the third message230to second device210-a. Additionally or alternatively, there may be examples where second device210-atransmits the second message220and the fourth message235to first device205-a.

FIG.3illustrates an example of an SPP OAM configuration300that supports connection setup in an OAM-based communication system in accordance with aspects of the present disclosure. In some examples, SPP OAM configuration300may implement aspects of wireless communications system100or200. In this example, a transmitting device (e.g., UE or network entity) may include transmitter OAM components305and a receiving device (e.g., UE or network entity) may include receiver OAM components310.

In cases in which the wireless devices use an SPP methodology, the transmitting device may convert an electromagnetic wave315associated with an OAM mode index l=0 (e.g., a non-helical electromagnetic wave associated with mode-zero OAM) into an electromagnetic wave associated with an OAM mode index l≠0 (e.g., a helical electromagnetic wave associated with non-zero OAM mode) based on passing the electromagnetic wave through an aperture320and an SPP325. Such an SPP325may be associated with geometric constraints and may be able to generate an electromagnetic wave associated with a single OAM mode. Thus, the wireless device may use one SPP325to generate one OAM mode of an OAM beam335. As such, a wireless device may implement a different SPP325for each OAM mode of an OAM beam335.

The example ofFIG.3illustrates the use of two OAM modes (e.g., l=+1 and −1). In the transmitter OAM components, a first electromagnetic wave315-amay be provided to a first aperture320-aand a first SPP325-a(also referred to herein as a transmitter aperture and a transmitter SPP), and a second electromagnetic wave315-bmay be provided to a second aperture320-band a second SPP325-b(also referred to herein as a transmitter aperture and a transmitter SPP). A beam splitter/combiner330may combine the output of the first SPP325-aand the second SPP325-bto generate OAM beam335. The receiver OAM components310may receive the OAM beam335at a beam splitter/combiner340, which may provide instances of the OAM beam335to a third SPP325-cand a fourth SPP325-d(also referred to herein a receiver SPPs). The third SPP325-cand the fourth SPP325-dmay provide output to a first receiver aperture320-cand a second receiver aperture320-d(also referred to herein as a receiver apertures), respectively.

The third SPP325-cmay have geometric constraints corresponding to the first SPP325-aand thus the output of the first receiver aperture320-cmay correspond to the first electromagnetic wave315-a(e.g., for OAM Mode l=1). Likewise, the fourth SPP325-dmay have geometric constraints corresponding to the second SPP325-band thus the output of the second receiver aperture320-dmay correspond to the second electromagnetic wave315-b(e.g., for OAM Mode l=2). In devices that use SPP methodology, separate SPPs325may be used for each OAM mode, and the number of usable OAM modes may correspond to the number of SPPs325at a device. As discussed, wireless devices may also use a UCA methodology for OAM communications, an example of which is discussed with reference toFIG.4.

FIG.4illustrates an example of a UCA OAM configuration400that supports connection setup in an OAM-based communication system in accordance with aspects of the present disclosure. In some examples, UCA OAM configuration400may implement aspects of wireless communications system100or200. In this example, a transmitting device (e.g., UE or network entity) may include OAM transmitter UCA antennas405and a receiving device (e.g., UE or network entity) may include OAM receiver UCA antennas410.

In some aspects, one or both of the OAM transmitter UCA antennas405or the OAM receiver UCA antennas410may be implemented as a planar array of antenna elements which may be an example of or otherwise function as a (massive or holographic) MIMO array or an intelligent surface. In some cases, the transmitting device may identify a set of antenna elements415of the planar array that form a transmitter UCA, and a receiving device may identify a set of antenna elements445of the planar array that form a receiver UCA.

Upon selecting the set of antenna elements from the planar array, the OAM transmitter may apply a weight435to each of the selected antenna elements415based on the OAM mode index l of the transmitted OAM beam and one or more spatial parameters associated with each antenna element. In cases in which UCA methodology is used to generate an OAM beam, the transmitting device may identify the set of antenna elements415on a circular array of antenna elements and may load a first set of weights420to each of the identified antenna elements based on a first OAM mode index (e.g., l=0). Further, for other OAM mode indices, other weights may be used for the set of antenna elements415, such as a second OAM mode index (e.g., l=+1) that may use a second set of weights425and a third OAM mode index (e.g., l=−1) that may use a third set of weights430.

For example, to generate an OAM beam with an OAM mode index (e.g., l=0), the OAM transmitter may load a weight435to each antenna element415on the UCA based on an angle440measured between a reference line on the UCA (e.g., the x-axis of the plane on which the UCA is located, where the origin is at the center of the UCA) and the antenna element, the OAM mode index l, and i (e.g., for complex-valued weights, which may alternatively be denoted as j in some cases). In some cases, for instance, the weight for an antenna element n may be proportional to ei*l**φn, where φnis equal to the angle440measured between the reference line on the UCA and the antenna element n. By multiplying respective beamforming weights435of each set of weights420through430(e.g., for the first set of weights420, w1[w1,1, w1,2, . . . , w1,8]T) onto each antenna, a signal port (also referred to herein as an OAM-formed port) may be generated. If the weight435of each antenna element415is equal to eiφl, where φ is the angle of antenna element415in the circle (e.g., angle440for antenna element415-g), and l is the OAM mode index, then each set of weights420through430provides a beamformed port that is equivalent OAM mode 1. By using different beamforming weights eiφl′, where l′≠l, multiple OAM modes may be generated.

At the OAM receiver UCA antennas410, the receiving device may include antenna elements445(also referred to herein as receive antenna elements) equipped in a circle. The channel matrix may be denoted from each transmit antenna to each receive antenna as H, and for the beamformed channel matrix {tilde over (H)}=H·[w1, w2, . . . , wL], any two columns of H are orthogonal which means the beamformed ports have no crosstalk.

Accordingly, OAM-based communication may realize a high-level spatial multiplexing degree efficiently. Further, the eigen-based transmit precoding weights and receive combining weights of UCA-based OAM are constantly equal to a discrete Fourier transform (DFT) matrix, which is irrelevant to communication parameters (e.g., distance, aperture size and carrier frequency), and thus UCA-based OAM may be implemented at relatively low cost.

In some systems, for single-circle UCA-based OAM performance, performance parameters such as OAM multiplexing degree and throughput may be based on parameter settings associated with the UCA, such as a radius of a UCA and an operating frequency. For example, a larger radius may support a relatively higher OAM multiplexing degree. In some examples, a higher operating frequency may support a relatively higher OAM multiplexing degree. In some cases, parameter settings such as a relatively large radius and high frequency may support a relatively large number of concurrent OAM modes (e.g., multiple tens).

FIG.5illustrates an example of a multi-circle UCA-based OAM configuration500that supports connection setup in an OAM-based communication system in accordance with aspects of the present disclosure. In some examples, multi-circle UCA-based OAM configuration500may implement aspects of wireless communications system100or200. In this example, a transmitting device (e.g., UE, network entity, a first device) may include OAM transmitter UCA antennas505and a receiving device (e.g., UE, network entity, a second device) may include OAM receiver UCA antennas510.

As described with reference toFIG.4, device may be configured with a UCA antenna to realize OAM-based communications. In some implementations, a device may be configured with multiple UCA antenna circles515(also referred to herein as UCA circles515). For example, a transmitting device and a receiving device may each be configured with multiple co-axis UCA antenna circles515(also referred to herein as UCA circles515). A transmitting device may be configured with OAM transmitter UCA antennas505and a receiving device may be configured with OAM receiver UCA antennas510. A transmitting device and a receiving device may be configured with the same number of UCA circles515, or a different number of UCA circles. In the example depicted byFIG.5, a transmitting device and a receiving device may each be configured with five antenna circles, where each antenna circle may include one or more antenna elements530. Each UCA circle515may include any number of antenna elements530.

Further a device may be configured with UCA circles515(e.g., UCA circles515-athrough515-e) at a transmitter of the device, and the same device may be configured with UCA circles515(e.g., UCA circles515-fthrough515-j) at a receiver of the device. For example, a transmitting device (e.g., first device205-aor second device210-aas described with reference toFIG.2) may be configured with UCA circles515-a,515-b,515-c,515-d, and515-e(also referred to herein as downlink transmitter circles of the transmitting device), and the receiving device (e.g., first device205-aor second device210-aas described with reference toFIG.2) may be configured with UCA circles515-fthrough515-j(also referred to herein as downlink receiver circles of the receiving device) at a receiver of the receiving device. In some examples, UCA circles515-a,515-b,515-c,515-d, and515-emay be configured to receive transmissions (e.g., uplink transmissions), and UCA circles515-fthrough515-jmay be configured to transmit transmissions (e.g., uplink transmissions).

For example, a transmitting device may be configured with UCA circles515-a,515-b,515-c,515-d, and515-e(also referred to herein as downlink transmitter circles), where the number of antenna elements530included on each UCA circle515may be the same, different, or partially the same. In some examples, the receiving device may be configured with UCA circles515-f,515-g,515-h,515-i, and515-j(also referred to herein as downlink receiver circles), where the number of antenna elements530included on each of the UCA circles515-f,515-g,515-h,515-i, and515-jmay be the same, different, or partially the same.

For example, all UCA circles515may include the same number of antenna elements530, or each UCA circle515may include a different number of antenna elements530, or a subset of the UCA circles515may include the same number of antenna elements530. In some cases, the number of antenna elements530included on each UCA circle515may be based on the radius of the UCA circle515. Each of the UCA circles515that a device is configured with may have the same radius, or different radii, or some may be the same and some may be different. The UCA circles515a device is configured with may be configured in any orientation. For example, the UCA circles may each have a different radius and be interlaid, such that one UCA circle515sits inside another UCA circle515, and so on, as depicted inFIG.5.

In some cases, intra-circle OAM transmissions (e.g., OAM signals, OAM streams) may be orthogonal to each other, such that OAM transmissions from the same UCA circle515may not interfere with one another. As such, OAM transmissions from the same UCA circle515of different OAM states or modes may be multiplexed together to increase the capacity of an OAM link. In some cases, inter-circle OAM transmissions (e.g., OAM signals, OAM streams) may be orthogonal with different OAM modes, such that OAM transmissions from different UCA circles515transmitted according to different OAM modes may be orthogonal to one another. Inter-circle OAM transmissions may be non-orthogonal with OAM transmissions of the same OAM mode, such that OAM transmissions from different UCA circles515transmitted according to the same OAM mode may be non-orthogonal to one other (e.g., cause interference to another other, cause cross-talk). For each OAM mode, inter-circle interference may exist where the OAM transmissions stream from one UCA circle515is mutually interfered with the OAM transmission stream transmitted from another UCA circle515, where the two OAM transmission streams have the same OAM mode.

For example, multiple OAM transmissions may be transmitted from each UCA circle515, where the intra-circle transmissions may be multiplexed if the intra-circle transmissions are associated with different modes. For example, a transmitting device may transmit a first OAM transmission according to OAM mode 1 via UCA circle515-e, and a second OAM transmission according to OAM mode 2 via UCA circle515-e. The transmitting device may transmit a third OAM transmission according to OAM mode 1 via UCA circle515-d, a fourth OAM transmission according to OAM mode 2 via UCA circle515-d, a fifth OAM transmission according to OAM mode 1 via UCA circle515-c, a sixth OAM transmission according to OAM mode 2 via UCA circle515-c, a seventh OAM transmission according to OAM mode 1 via UCA circle515-b, and an eighth OAM transmission according to OAM mode 2 via UCA circle515-b. The transmitting device may transmit one or more OAM transmissions according to one or more OAM modes via UCA circle515-a.

In some aspects, the transmitting device may transmit an OAM transmission according to an OAM mode 0, for example, by using the same weight (e.g., a weight of one) for all antenna elements530of a UCA circle515(e.g., UCA circle515-b) of the transmitting device. In some other aspects, the transmitting device may transmit an OAM transmission according to OAM mode 0 by using the same weight (e.g., a weight of one) for all antenna elements530of multiple UCA circles (e.g., UCA circle515-band UCA circle515-c) of the transmitting device.

In some aspects, the transmitting device may transmit an OAM transmission according to OAM mode 0 (also referred to herein as OAM order 0) via the center antenna (e.g., UCA circle515-a) of the transmitting device. In some aspects, the transmitting device may generate a signal of OAM mode 0 via any of the UCA circles515(e.g., UCA circle515-bthrough UCA circle515-e).

In some examples, multiple OAM transmissions may be received by each UCA circle515, where the intra-circle transmissions may be demultiplexed if the intra-circle transmissions are associated with different modes. For example, a receiving device may receive a first OAM transmission according to OAM mode 1 via UCA circle515-j, and a second OAM transmission according to OAM mode 2 via UCA circle515-j. The receiving device may receive a third OAM transmission according to OAM mode 1 via UCA circle515-i, a fourth OAM transmission according to OAM mode 2 via UCA circle515-i, a fifth OAM transmission according to OAM mode 1 via UCA circle515-h, a sixth OAM transmission according to OAM mode 2 via UCA circle515-h, a seventh OAM transmission according to OAM mode 1 via UCA circle515-g, and an eighth OAM transmission according to OAM mode 2 via UCA circle515-g. The receiving device may receive one or more OAM transmissions according to one or more OAM modes (e.g., the null mode, mode 0) via UCA circle515-f.

In some aspects, the receiving device may receive an OAM transmission according to OAM mode 0, for example, by using the same weight (e.g., a weight of one) for all antenna elements530of a UCA circle515(e.g., UCA circle515-g) of the receiving device. In some other aspects, the receiving device may receive an OAM transmission according to OAM mode 0 by using the same weight (e.g., a weight of one) for all antenna elements530of multiple UCA circles (e.g., UCA circle515-gand UCA circle515-h) of the receiving device.

In some aspects, the receiving device may receive an OAM transmission according to OAM mode 0 (also referred to herein as OAM order 0) via the center antenna (e.g., UCA circle515-f) of the receiving device. In some other aspects, the receiving device may receive a signal of OAM mode 0 via any of the UCA circles515(e.g., UCA circle515-fthrough UCA circle515-j).

As described herein, intra-circle OAM transmissions may be orthogonal. As such, the first and second OAM transmissions may be orthogonal to one another, and may, in some cases, be multiplexed. Similarly, the third and fourth transmissions may be orthogonal to one another, the fifth and sixth transmissions may be orthogonal to one another, and the seventh and the eighth transmission may be orthogonal to one another. Further, as described herein, inter-circle OAM transmissions transmitted via different OAM mode may be orthogonal. As such, the first transmission may be orthogonal with the fourth transmission, the sixth transmission, and the eight transmission, for example. Further, as described herein, inter-circle OAM transmissions transmitted via the same OAM mode may be non-orthogonal. As such, the first transmission may be non-orthogonal with the third transmission, the fifth transmission, and the seventh transmission, for example.

In some cases, a transmitting device may transmit the first transmission through the eighth transmissions, as described herein, simultaneously. As such, the first transmission through the eighth transmission may be transmitted via a multi-circle UCA panel, such as multiplexing panel520that may multiplex one or more of the transmissions into OAM multiplexed signals525. For example, the intra-circle transmission may be multiplexed with each other, such as the first transmission and the second transmission. In another example, each of the first transmission through the eighth transmission may be multiplexed using different UCA circles or OAM modes. The transmitting device may transmit the one or more OAM multiplexed signals525to a receiving device, where the OAM receiver UCA antennas510of the receiving device may spread the one or more OAM multiplexed signals.

Further, although shown in the example depicted inFIG.5as two modes (a first and a second mode) being transmitted by each UCA circle515, each UCA circle515may transmit any number of OAM transmissions according to any number of OAM modes. The number of OAM transmissions from each UCA circle515may be the same, different, or partially the same, such that all UCA circles515at a device may transmit the same number of transmissions, a different number of transmissions, or some UCA circles515may transmit the same number of transmissions while other UCA circles may transmit a different number of transmissions. Further, although each device is depicted inFIG.5as being configured with5UCA circles515, a device may be configured with any number of UCA circles515.

In some cases, as inter-circle OAM transmissions of the same mode may interfere with one another, a transmitting device may be configured to transmit a particular mode via a particular UCA circle515so as to mitigate interference caused by inter-circle OAM transmissions of the same mode. A transmitting device, or a receiving device, or both may be configured to determine a transmission scheme for the transmitting device that indicates which UCA circle515should be used to transmit which OAM mode. In some implementations, the channel gains of OAM transmission streams may be different from each UCA circle515for each OAM mode for a set of parameters. The parameters may include system parameters such as a communication distance between a transmitting device and a receiving device, the radius of each transmitter UCA circle515, the radius of each receiver UCA circle515, carrier frequency, number of antenna elements530in each UCA circle515. For example, for a set of system parameters (in which the parameters are held constant), an OAM mode of 2 or −2 may have a largest channel gain when transmitted via a UCA transmitter circle radius of 0.8 meters. In another example, for the same set of system parameters, an OAM mode of 1 or −1 may have a largest channel gain when transmitted via a UCA transmitter circle radius of 0.6 meters. In another example, for the same set of system parameters, an OAM mode of 0 may have a largest channel gain when transmitted via a UCA transmitter circle radius of 0.2 meters. Therefore, to achieve high data throughput, a transmitting device may be configured to transmit an OAM transmission via an OAM mode-UCA circle pairing that results in a large (or largest) channel gain.

As described with reference toFIGS.2and6, a transmitting device and a receiving device may establish an OAM communications connection by exchanging messages over communications links (e.g., communications link225-aand a communications link225-bas described with reference toFIG.2) according to any OAM mode. In an example, the transmitting device and the receiving device may exchange messages using OAM mode 0, where OAM mode 0 may correspond to a UCA circle515. In some cases, when transmitting signals based on a configured set of system parameters, a signal transmitted using OAM mode 0 may have the relatively smallest power dispersion with respect to wireless propagation of the signal, for example, compared to signals that are transmitted using other OAM modes (e.g., OAM mode 1, OAM mode 2, etc.).

Based on establishing the OAM communications connection using the OAM mode 0, the transmitting device and the receiving device may communicate one or more data transmissions according to a set of OAM modes (e.g., where the OAM modes correspond to respective a UCA circle515).

FIG.6illustrates an example of a process flow600that supports connection setup in an OAM-based communication system in accordance with aspects of the present disclosure. The process flow600may illustrate an example message and signal exchange supportive of establishing an OAM communications connection according to aspects of the present disclosure.

The first device205-band the second device210-bmay be examples of the corresponding devices (e.g., wireless devices) described with reference toFIGS.1through5, where the first device205-band the second device210-bmay be the same device or may be different devices. The first device205-band the second device210-bmay each be a UE, a network entity, an IAB node, etc. Alternative examples of the following may be implemented, where some steps are performed in a different order than described or are not performed at all. In some cases, steps may include additional features not mentioned below, or further steps may be added.

According to example aspects of the present disclosure, the first device205-band the second device210-bmay establish an OAM communications connection between the first device205-band the second device210-b. For example, the first device205-band the second device210-bmay exchange messages (e.g., four messages) over an uplink communications link (e.g., communications link225-adescribed with reference toFIG.2) and a downlink communications link (e.g., a communications link225-bdescribed with reference toFIG.2) according to an OAM mode (e.g., OAM mode 0). Based on OAM related parameters or OAM related information included in the messages, the first device205-band the second device210-bmay achieve a successful directional alignment (co-axial alignment) between the first device205-band the second device210-b. The first device205-band the second device210-bmay determine one or more OAM modes (e.g., OAM mode 1, 2, etc.) for communication between the first device205-band the second device210-bbased on the establishing the directional alignment.

At605, the first device205-bmay monitor for wake-up signals over a set of resources allocated for wake-up signals. In some examples, the first device205-bmay monitor for the wake-up signal via an OAM mode (e.g., OAM mode 0). For example, the first device205-bmay enter a standby or sleep state to maintain low power consumption, and the first device205-bmay exit the standby or sleep state based on receiving a wake-up signal from the second device210-b. In some aspects, the first device205-bmay monitor for wake-up signals over a set of time and frequency resources allocated for transmitting and receiving wake-up signals. Example aspects of the wake-up signal are described with reference toFIG.7.

At610, the first device205-bmay receive a wake-up signal from the second device210-bvia the OAM mode (e.g., OAM mode 0). In some aspects, the first device205-bmay receive the wake-up signal via an uplink communications link.

At615, the first device205-bmay transmit a first message to the second device210-bvia the OAM mode (e.g., OAM mode 0). The first message may be, for example, a system information and synchronization message. In an example, the first device205-bmay transmit the first message to the second device210-bvia a downlink communications link.

The first message may include a synchronization signal. In some cases, the synchronization signal may be a timing synchronization signal. For example, based on the synchronization signal, the first device205-band the second device210-bmay synchronize timing for exchanging of subsequent messages (e.g., second through fourth messages described herein) between the first device205-band the second device210-b.

In some aspects, the first message may include first positional information associated with downlink transmissions by the first device205-b. In an example, the first positional information may include GPS positioning information or GNSS positioning information associated with the first device205-b. In some examples, the first positional information may include an OAM circle center (e.g., UCA circle515-adescribed with reference toFIG.5) of the first device205-b. In some aspects, the OAM circle center (e.g., UCA circle515-adescribed with reference toFIG.5) of the first device205-bmay be for transmitting the first message, and the OAM circle center may be referred to as a transmitter OAM circle center of the first device205-b. In some aspects, the first positional information may include direction information associated with the OAM circle center of the first device205-b.

In some other aspects, the first positional information included in the first message may include positional information of the first device205-b.

In an example, the first positional information included in the first message may include an OAM circle center of the first device205-b(e.g., UCA circle515-aor UCA circle515-fdescribed with reference toFIG.5) for transmission or reception by the first device205-b. In some aspects, the first positional information may include direction information associated with the OAM circle center of the first device205-b. In some cases, the first positional information included in the first message may include a request for positional information of the second device210-b. For example, the requested positional information of the second device210-bmay include an OAM circle center (e.g., UCA circle515-aor UCA circle515-fdescribed with reference toFIG.5) of the second device210-b. In some aspects, the requested positional information of the second device210-bmay include direction information associated with the OAM circle center of the second device210-b.

In some examples, the first message may include a set (or list) of OAM parameters associated with transmissions (e.g., downlink transmissions) by the first device205-b. For example, the OAM parameters may include a list of candidate OAM modes associated with the first device205-b. The candidate OAM modes may correspond to, for example, UCA circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5) of the first device205-b.

In some examples, the OAM parameters may include a quantity of downlink transmitter circles associated with the first device205-b. For example, the OAM parameters may indicate a quantity of four downlink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5) of the first device205-b. In some aspects, the OAM parameters may indicate a radius associated with each of the downlink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5). In some other aspects, the OAM parameters may include a quantity of antenna elements (e.g., antenna elements530) associated with each of the downlink transmitter circles.

In some examples, the OAM parameters may include a quantity of OAM modes simultaneously used for each of the downlink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5) of the first device205-b. For example, the OAM parameters may indicate that the first device205-bsupports transmitting (or has transmitted) a first quantity of OAM modes simultaneously via a first UCA circle (e.g., UCA circle515-eas described with reference toFIG.5) and a second quantity of OAM modes simultaneously via a second UCA circle (e.g., UCA circle515-eas described with reference toFIG.5).

In some examples, the OAM parameters may include a quantity of uplink receiver circles associated with the first device205-b. For example, the OAM parameters may indicate a quantity of four uplink receiver circles (e.g., UCA circles515-fthrough515-jdescribed with reference toFIG.5) of the first device205-b. In some aspects, the OAM parameters may indicate a radius associated with each of the uplink receiver circles. In some other aspects, the OAM parameters may include a quantity of antenna elements (e.g., antenna elements530) associated with each of the uplink receiver circles.

In some examples, the OAM parameters may include a quantity of OAM modes simultaneously used for each of the uplink receiver circles (e.g., UCA circles515-fthrough515-jdescribed with reference toFIG.5) of the first device205-b. For example, the OAM parameters may indicate that the first device205-bsupports receiving a first quantity of OAM modes simultaneously via a first UCA circle (e.g., UCA circle515-fas described with reference toFIG.5) and a second quantity of OAM modes simultaneously via a second UCA circle (e.g., UCA circle515-gas described with reference toFIG.5).

In some aspects, the first device205-bmay transmit the first message to the second device210-bbased on (e.g., in response to) receiving the wake-up signal from the second device210-b. For example, the first device205-bmay refrain from procedures for establishing an OAM communications link with the second device210-b(e.g., refrain from exchanging messages over the uplink communications link and the downlink communications link) until the first device205-breceives a wake-up signal. Additionally, or alternatively, the first device205-bmay the transmit first message to the second device210-bindependent of monitoring for (or receiving) a wake-up signal from the second device210-b.

In some aspects, the first device205-bmay transmit the first message according to a set of parameters associated with transmitting the first message. In an example, the parameters may include a periodicity or interval for transmitting the first message, and the first device205-bmay transmit the first message periodically based on the periodicity or interval. In some examples, the first device205-bmay transmit the first message over a set of time and frequency resources (e.g., radio resources) allocated for transmitting the message.

Additionally, or alternatively, the first message may indicate a set of time and frequency resources for communicating additional (e.g., subsequent) messages between the first device205-band the second device210-b. For example, the first message may indicate a set of time and frequency resources for communicating any one or more of a second message, a third message, or a fourth message between the first device205-band the second device210-bas described herein. Example aspects of the periodicity and resources associated with transmitting the first message, and examples of resources indicated by the first message, are described with reference toFIG.7.

In some aspects, the first device205-bmay transmit the first message using a center radiator of one or more transmitter circles (e.g., UCA circles) of the first device205-b. For example, the first device205-bmay transmit the first message using a center antenna (e.g., UCA circle515-adescribed with reference toFIG.5) of the first device205-b. In some aspects, the first device205-bmay transmit the first message using a quantity of radiators of one or more transmitter circles (e.g., UCA circles) of the first device205-b. For example, the first device205-bmay transmit the first message using each of the antennas (e.g., each of the antennas in one or more of UCA circle515-bthrough515-edescribed with reference toFIG.5) of the first device205-b.

At620, the first device205-bmay receive a second message from the second device210-b, via the OAM mode (e.g., OAM mode 0). The second message may be, for example, a connection request message. In some aspects, the second device210-bmay transmit (and the first device205-bmay receive) the second message in response to the first message. In an example, the second device210-bmay transmit the second message to the first device205-bvia an uplink communications link (e.g., communications link225-adescribed with reference toFIG.2).

In some aspects, the second message may include second positional information associated with uplink transmissions by the second device210-b. In an example, the second positional information may include GPS positioning information or GNSS positioning information associated with the second device210-b. In some examples, the second positional information may include an OAM circle center of the second device210-b(e.g., UCA circle515-adescribed with reference toFIG.5) for transmission by the second device210-b. In some aspects, the OAM circle center (e.g., UCA circle515-adescribed with reference toFIG.5) of the second device210-bmay be for transmitting the second message, and the OAM circle center may be referred to as a transmitter OAM circle center of the second device210-b. In some aspects, the second positional information may include direction information associated with the transmitter OAM circle center of the second device210-b.

In some examples, the second positional information may include an OAM circle center of the second device210-b(e.g., UCA circle515-fdescribed with reference toFIG.5) for reception by the second device210-b. In some aspects, the OAM circle center (e.g., UCA circle515-fdescribed with reference toFIG.5) of the second device210-bfor receiving transmissions may be referred to as a receiver OAM circle center associated with the second device210-b). In some aspects, the second positional information may include direction information associated with the OAM circle center of the second device210-b. In some aspects, the second positional information may include direction information associated with the receiver OAM circle center of the second device210-b.

In some examples, the second message may include a set (or list) of OAM parameters associated with transmissions or receptions (e.g., uplink transmissions, downlink reception) by the second device210-b. For example, the OAM parameters may include a list of candidate OAM modes associated with the second device210-b. The candidate OAM modes may correspond to, for example, UCA circles (e.g., UCA circles515-bthrough515-e, described with reference toFIG.5) of the second device210-b.

In some examples, the OAM parameters may include a quantity of uplink transmitter circles associated with the second device210-b. For example, the OAM parameters may indicate a quantity of four uplink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5) of the second device210-b. In some aspects, the OAM parameters may indicate a radius associated with each of the uplink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5). In some other aspects, the OAM parameters may include a quantity of antenna elements (e.g., antenna elements530) associated with each of the uplink transmitter circles.

In some examples, the OAM parameters may include a quantity of OAM modes simultaneously used for each of the uplink transmitter circles (e.g., UCA circles515-bthrough515-edescribed with reference toFIG.5) of the second device210-b. For example, the OAM parameters may indicate that the second device210-bsupports transmitting (or has transmitted) a first quantity of OAM modes simultaneously via a first UCA circle (e.g., UCA circle515-das described with reference toFIG.5) and a second quantity of OAM modes simultaneously via a second UCA circle (e.g., UCA circle515-eas described with reference toFIG.5).

In some examples, the OAM parameters may include a quantity of downlink receiver circles associated with the second device210-b. For example, the OAM parameters may indicate a quantity of four downlink receiver circles (e.g., UCA circles515-fthrough515-jdescribed with reference toFIG.5) of the second device210-b. In some aspects, the OAM parameters may indicate a radius associated with each of the downlink receiver circles. In some other aspects, the OAM parameters may include a quantity of antenna elements (e.g., antenna elements530) associated with each of the downlink receiver circles.

In some examples, the OAM parameters may include a quantity of OAM modes simultaneously used for each of the downlink receiver circles (e.g., UCA circles515-fthrough515-jdescribed with reference toFIG.5) of the second device210-b. For example, the OAM parameters may indicate that the second device210-bsupports receiving a first quantity of OAM modes simultaneously via a first UCA circle (e.g., UCA circle515-fas described with reference toFIG.5) and a second quantity of OAM modes simultaneously via a second UCA circle (e.g., UCA circle515-gas described with reference toFIG.5).

In some aspects, the second device210-bmay transmit the second message using a center radiator of one or more transmitter circles (e.g., UCA circles) of the second device210-b. For example, the second device210-bmay transmit the second message using a center antenna (e.g., UCA circle515-adescribed with reference toFIG.5) of the second device210-b. In some aspects, the second device210bmay transmit the second message using a quantity of radiators of one or more transmitter circles (e.g., UCA circles) of the second device210-b. For example, the second device210bmay transmit the second message using each of the antennas (e.g., each of the antennas in one or more of UCA circle515bthrough515edescribed with reference toFIG.5) of the second device210b.

At625, the first device205-bmay align the transmitter OAM circle center associated with the first device205-b(e.g., UCA circle515-adescribed with reference toFIG.5) with the receiver OAM circle center associated with the second device210-b(e.g., UCA circle515-fdescribed with reference toFIG.5). In an example, the first device205-bmay align the OAM circle centers based on a combination of the first positional information associated with the transmitter OAM circle center of the first device205-b(e.g., as communicated to the second device210-busing the first message), the receiver OAM circle center of the second device210-b(e.g., as indicated by the second device210-bin the second message), and directional alignment information (e.g., as communicated to the second device210-bin the third message).

In an example, the first device205-bmay rotate or position an OAM transmitter of the first device205-bto realize co-axial alignment with an OAM receiver of the second device210-b. For example, the first device205-bmay rotate or position UCA antennas of the first device205-b(e.g., UCA circles515-athrough515-e) to realize co-axial alignment with one or more UCA antennas of the second device210-b(e.g., UCA circles515-fthrough515-j). In some aspects, the first device205-bmay rotate the axial direction of OAM circles of the first device205-b(e.g., UCA circles515-athrough515e) towards the position (coordinates) of the second device210-b. In some aspects, co-axial alignment may include the OAM transmitter of the first device205-band the OAM receiver of the second device210-bsharing a common axis. In some cases, the common axis may be an axis common to (e.g., intersecting) both the transmitter OAM circle center of the first device205-b(e.g., UCA circle515-adescribed with reference toFIG.5) and the receiver OAM circle center of the second device210-b(e.g., UCA circle515-fdescribed with reference toFIG.5). For example, the common axis may be perpendicular to both a plane associated with the transmitter OAM circles of the first device205-band a plane associated with the receiver OAM circles of the second device210-b

At630, the first device205-bmay transmit a third message to the second device210-bbased on the second message. The third message may be, for example, a directional alignment request message. In some aspects, the third message may include directional alignment information associated with transmitting a signal (e.g., an optical signal, a radio signal, a directional signal associated with one or more beams, an omnidirectional signal) from the first device205-b. In an example, the directional alignment information may include steering information associated with the signal. In some examples, the steering information may include a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

In some examples, the first device205-bmay transmit the third message using a center radiator of one or more transmitter circles (e.g., UCA circles) of the first device205-b. For example, the first device205-bmay transmit the third message using a center antenna (e.g., UCA circle515-adescribed with reference toFIG.5) of the first device205-b. In some aspects, the first device205-bmay transmit the third message using a quantity of radiators of one or more transmitter circles (e.g., UCA circles) of the first device205-b. For example, the first device205-bmay transmit the third message using each of the antennas (e.g., each of the antennas in one or more of UCA circle515-bthrough515-edescribed with reference toFIG.5) of the first device205-b.

At635, the first device205-bmay transmit a signal to the second device210-b. In some aspects, the first device205-bmay transmit the signal based on the first positional information of the first device205-b. In some aspects, the first device205-bmay transmit the signal based on the second positional information of the second device210-b. For example, the first device205-bmay transmit the signal based on the transmitter OAM circle center associated with the first device205-b(e.g., as communicated to the second device210-busing the first message) and the receiver OAM circle center associated with the second device210-b(e.g., as indicated by the second device210-bin the second message).

At640, the second device210-bmay align the receiver OAM circle center associated with the second device210-b(e.g., UCA circle515-fdescribed with reference toFIG.5) with the transmitter OAM circle center associated with the first device205-b(e.g., UCA circle515-adescribed with reference toFIG.5). In an example, the second device210-bmay align the OAM circle centers based on a combination of the first positional information associated with the transmitter OAM circle center of the first device205-b(e.g., as communicated to the second device210-busing the first message), the receiver OAM circle center of the second device210-b(e.g., as indicated by the second device210-bin the second message), and the directional alignment information (e.g., as communicated to the second device210-bin the third message).

In an example, the second device210-bmay rotate or position an OAM receiver of the second device210-bto realize co-axial alignment with an OAM transmitter of the first device205-b. For example, the second device210-bmay rotate or position UCA antennas of the second device210-b(e.g., UCA circles515-fthrough515-j) to realize co-axial alignment with one or more UCA antennas of the first device205-b(e.g., UCA circles515-athrough515-e). In some aspects, the second device210-bmay rotate the axial direction of OAM circles of the second device210-b(e.g., UCA circles515-fthrough515-j) towards the position (coordinates) of the first device205-b. In some aspects, co-axial alignment may include the OAM transmitter of the first device205-band the OAM receiver of the second device210-bsharing a common axis. In some cases, the common axis may be an axis common to both the transmitter OAM circle center of the first device205-b(e.g., UCA circle515-adescribed with reference toFIG.5) and the receiver OAM circle center of the second device210-b(e.g., UCA circle515-fdescribed with reference toFIG.5).

At645, the second device210-bmay transmit (and the first device205-bmay receive) a fourth message indicating whether the signal was successfully received by the second device210-b. The fourth message may be, for example, a directional alignment response message. The second device210-bmay transmit the fourth message via the OAM mode (e.g., OAM mode 0). In some aspects, the fourth message may include an indication of successful alignment between the first device205-band the second device210-b. In some examples, the fourth message may include an indication of an unsuccessful alignment between the first device205-band the second device210-b.

In some examples, the second device210-bmay transmit the fourth message using a center radiator of one or more transmitter circles (e.g., UCA circles) of the second device210-b. For example, the second device210-bmay transmit the fourth message using a center antenna (e.g., UCA circle515-adescribed with reference toFIG.5) of the second device210-b. In some aspects, the second device210-bmay transmit the fourth message using a quantity of radiators of one or more transmitter circles (e.g., UCA circles) of the second device210-b. For example, the second device210-bmay transmit the fourth message using each of the antennas (e.g., each of the antennas in one or more of UCA circle515-bthrough515-edescribed with reference toFIG.5) of the second device210-b.

According to example aspects of the present disclosure, the first device205-band the second device210-bmay communicate the first through fourth messages using time-domain multiplexing. In some cases, the first device205-band the second device210-bmay communicate the first through fourth messages using frequency-domain multiplexing. In some other cases, the first device205-band the second device210-bmay communicate the first through fourth messages using spatial-domain multiplexing.

In some cases, the first device205-band the second device210-bmay communicate the first through fourth messages using based on different polarizations (also referred to herein as dimensions), where the polarizations may correspond to SAM of electromagnetic waves. For example, the first device205-bmay perform any or all of transmitting the first message, receiving the second message, transmitting the third message, and receiving the fourth message based on a first polarization, a second polarization different from the first polarization, or both. For example, the first polarization or the second polarization may be applied to each transmission element of the first device205-b. In some examples, the first polarization or the second polarization may be applied to one or more downlink transmitter circles of the first device205-b(e.g., UCA circles515-athrough515-eas described with reference toFIG.5). In some aspects, the first polarization or the second polarization may be applied to one or more antenna elements of the first device205-b(e.g., antenna elements530as described with reference toFIG.5).

Although the present example describes first device205-btransmitting the first message, the third message, and the signal and second device210-btransmitting the second message, the fourth message, and, in some examples, the wake-up signal, there may be examples where first device205-bmay transmits the second message, the fourth message, and, in some examples, the wake-up signal to second device210-a. Additionally or alternatively, there may be examples where second device210-btransmits the first message, the third message, and the signal to first device205-b.

In some cases, the polarizations may increase the number of different waveforms or signals that can be transmitted or received by a device (e.g., first device205-b, second device210-b). For example, the first device205-bmay generate a waveform using one of two polarizations. In another example, the first device205-bmay generate a waveform using the other of the two polarizations.

In some aspects, the first polarization of the first device205-bmay include a horizontal polarization with respect to a plane of the first device205-b, and the second polarization of the first device205-bmay include a vertical polarization with respect to the plane. In some other aspects, the first polarization of the first device205-bmay include a first rotation direction (e.g., clockwise rotation direction) associated with a circular polarization with respect to a plane of the first device205-b, and the second polarization of the first device205-bmay include a second rotation direction (e.g., counter-clockwise rotation direction) associated with the circular polarization. In some example aspects, the first polarization of the first device205-bmay include a first rotation direction (e.g., clockwise rotation direction) associated with an elliptical polarization with respect to a plane of the first device205-b, and the second polarization of the first device205-bmay include a second rotation direction (e.g., counter-clockwise rotation direction) associated with the elliptical polarization.

Additionally, or alternatively, the second device210-bmay perform any of receiving the first message, transmitting the second message, receiving the third message, and transmitting the fourth message based on a first polarization, a second polarization, or both. In some aspects, the polarizations based on which the first device205-bcommunicates messages (e.g., the first through fourth messages) and the polarizations based on which the second device210-bcommunicates messages (e.g., the first through fourth messages) may be the same or different from one another. For example, the first polarization of the first device205-bmay be the same as the first polarization of the second device210-b. In some other aspects, the first polarization of the first device205-bmay be different from the first polarization of the second device210-b. In another example, the second polarization of the first device205-bmay be the same as the second polarization of the second device210-b. In some other aspects, the second polarization of the first device205-bmay be different from the second polarization of the second device210-b.

In an example, the first polarization and the second polarization associated with the second device210-bmay be applied to each transmission element of the second device210-b. In some examples, the first polarization and the second polarization may be applied to one or more downlink receiver circles of the second device210-b(e.g., UCA circles515-fthrough515-jas described with reference toFIG.5). In some aspects, the first polarization and the second polarization may be applied to one or more antenna elements of the second device210-b(e.g., antenna elements530as described with reference toFIG.5).

In some aspects, the first polarization of the second device210-bmay include a horizontal polarization with respect to a plane of the second device210-b, and the second polarization of the second device210-bmay include a vertical polarization with respect to the plane. In some other aspects, the first polarization of the second device210-bmay include a first rotation direction (e.g., clockwise rotation direction) associated with a circular polarization with respect to a plane of the second device210-b, and the second polarization of the second device210-bmay include a second rotation direction (e.g., counter-clockwise rotation direction) associated with the circular polarization. In some example aspects, the first polarization of the second device210-bmay include a first rotation direction (e.g., clockwise rotation direction) associated with an elliptical polarization with respect to a plane of the second device210-b, and the second polarization of the second device210-bmay include a second rotation direction (e.g., counter-clockwise rotation direction) associated with the elliptical polarization.

In some aspects, the different polarizations may be supported by antennas or antenna elements of each device. For example, each antenna of a transmitting device (e.g., first device205-b) may be associated with a respective polarization. In some examples, each antenna of a receiving device (e.g., second device210-b) may be associated with a respective polarization. Any antenna element (e.g., antenna elements530as described with reference toFIG.5) of the first device205-bor the second device210-bmay support the generation of linear polarization, circular polarization, or elliptical polarization.

At645, the first device205-band the second device210-bmay communicate (e.g., transmit and receive) signaling messages and data transmissions according to a set of OAM modes. For example, the first device205-band the second device210-bmay communicate signaling messages and data transmissions using spatial multiplexing with multiple OAM modes. In some aspects, the first device205-band the second device210-bmay communicate signaling messages and data transmissions based on a successful alignment between the first device205-band the second device210-b(e.g., based on the fourth message indicating a successful alignment). In some examples, the signaling messages and data transmissions may be communicated in one of the different polarizations (e.g., multiple signaling messages or data transmissions may be simultaneously communicated using different polarizations for one or more of the OAM modes).

For example, the first device205-bmay transmit, via the OAM mode (e.g., OAM mode 0) used for communicating the first message through the fourth message, a configuration message (e.g., a PDSCH configuration message) for one or more downlink channel transmissions (e.g., PDSCH transmissions). In some aspects, the configuration message (e.g., PDSCH configuration message) may indicate a set of configured OAM modes (e.g., multiple OAM modes, for example, different from OAM mode 0) for the one or more downlink channel transmissions (e.g., PDSCH transmissions).

In some aspects, multiple (e.g., two) polarizations may be applied to any or all of the OAM modes used for communicating the first message through the fourth message (e.g., OAM mode 0) and the OAM modes used for downlink channel transmissions following co-axial alignment. In an example, the polarizations may be implemented by a device (e.g., first device205-b, second device210-b) according to selection-based procedures. For example, the first device205-bmay select a first polarization (e.g., horizontal polarization, clockwise rotation direction with respect to a circular polarization) for communicating one or more initial messages (e.g., the first message). In some examples, the first device205-bmay select a second polarization (e.g., vertical polarization, counter-clockwise rotation direction with respect to the circular polarization) for communicating subsequent messages (e.g., the second message through the fourth message).

In another example, the polarizations may be implemented by a device (e.g., first device205-b, second device210-b) according to diversity-based procedures. For example, the first device205-bmay use both a first polarization (e.g., horizontal polarization, clockwise rotation direction with respect to a circular polarization) and a second polarization (e.g., vertical polarization, counter-clockwise rotation direction with respect to the circular polarization) with transmit-diversity for communicating (e.g., transmitting) the first message and the third message to the second device210-b.

In some other examples, the polarizations may be implemented by a device (e.g., first device205-b, second device210-b) according to 2×2 MIMO techniques. For example, the first device205-band the second device210-bmay each use two antennas to establish up to two data streams between the devices. In some cases, the first device205-band the second device210-bmay use a first polarization (e.g., horizontal polarization, clockwise rotation direction with respect to a circular polarization) for respective antennas (e.g., a first antenna of the first device205-b, a first antenna of the second device210-b) associated with a first data stream. In some aspects, the first device205-band the second device210-bmay use a second polarization (e.g., vertical polarization, counter-clockwise rotation direction with respect to the circular polarization) for respective antennas (e.g., a second antenna of the first device205-b, a second antenna of the second device210-b) associated with a second data stream. In some cases, antennas of a receiving device (e.g., second device210-b) may or may not be completely aligned or isolated from one another.

According to example aspects of the present disclosure, communication between wireless devices (e.g., first device205-b, second device210-b) using a combination of different polarizations and multiple OAM modes as described herein may provide for independent sources of degrees of freedom, as polarization (e.g., SAM) and OAM mode may be considered as two independent properties of electromagnetic waves. In some cases, using a combination of different polarizations and multiple OAM modes may support an increased number (e.g., double) of data streams in OAM-based communications in MIMO compared to OAM-based communications that do not exploit polarization.

FIG.7illustrates an example700of a frame structure and wake-up signaling that supports connection setup in an OAM-based communications system in accordance with aspects of the present disclosure. In some examples, the frame structure and wake-up signaling of UCA OAM configuration400may implement aspects of wireless communications systems100,200, or process flow600described with reference toFIGS.1,2, and6. For example, the frame structure and wake-up signaling of UCA OAM configuration400may implement aspects of the message and signal exchange described with reference to process flow600.

The frame structure and wake-up signaling may be implemented by a first device205-a, a first device205-b, a second device210-a, or a second device210-bdescribed with reference toFIGS.2and6. Any of the first device205-a, the first device205-b, the second device210-a, or the second device210-bmay be a UE, a network entity, an IAB node, etc. as described herein.

For example, a first device (e.g., the first device205-a, the first device205-b) may monitor for wake-up signals over a set of resources705allocated for wake-up signals. In some aspects, the resources705may include a set of time and frequency resources allocated for transmitting and receiving wake-up signals. The resources705may be allocated for a wake-up signal period710.

In some aspects, the wake-up signal period may be repeated periodically (e.g., according to an interval). For example, the resources705included in the wake-up signal period710may be allocated to a time and frequency position in the wake-up signal period710(e.g., according to a start point of the wake-up signal period710, according to a start offset of the wake-up signal period710). In some examples, the first device and the second device may communicate wake-up signals based on achieving a timing synchronization between the first device and the second device.

In some aspects, the first device and the second device may achieve the synchronization by synchronizing with a third device. For example, the third device may be a GNSS satellite or GPS satellite, and the first device and the second device may synchronize with a signal (e.g., a GNSS signal or a GPS signal) transmitted by the third device. In some cases, the signal may be a beacon based on which the first device and the second device may synchronize their timing for transmitting and receiving wake-up signals.

In an example of the repeating of wake-up signal periods710(and resources705included in the wake-up signal periods710), a wake-up signal period710-amay include a set of resources705-aallocated for transmitting or receiving wake-up signals, a wake-up signal period710-bmay include a set of resources705-ballocated for transmitting or receiving wake-up signals, and so on.

In some examples, the first device may monitor for the wake-up signal via an OAM mode (e.g., OAM mode 0). For example, the first device may enter a standby or sleep state to maintain low power consumption, and the first device may exit the standby or sleep state based on receiving a wake-up signal from a second device (e.g., second device210-a, second device210-b). In SPP OAM configuration300, the first device may monitor for the wake-up signal during the wake-up signal periods710-athrough710-c.

In some aspects, the first device205-bmay receive the wake-up signal via an uplink communications link. During the wake-up signal period710-c, the first device may receive a wake-up signal within a duration corresponding to the resources705-c. In some cases, the first device may receive the wake-up signal via an uplink communications link.

The first device may transmit a first message (e.g., a system information and synchronization message) to the second device via the OAM mode (e.g., OAM mode 0). an example, the first device205-bmay transmit the first message to the second device over resources715allocated for transmitting the first message. In some cases, the first device may transmit the first message via a downlink communications link. In some aspects, the first device may transmit the first message at a temporal instance that overlaps with a wake-up signal period (e.g., wake-up signal period710-c) in which the first device successfully receives or detects a wake-up signal.

In an example, the first device may receive a configuration (e.g., from another device, such as a UE, a network entity, an IAB node, etc.) indicating the resources715allocated for transmitting the first message. In some cases, the configuration may indicate resources720(e.g., time and frequency resources) for receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof. In some aspects, the resources715and the resources720be repeat periodically (e.g., according to an interval).

Based on the configuration, the first device may determine the resources715over which to transmit the first message. In some examples, the first device may include, in the first message to the second device, an indication of the resources720allocated for receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof. Based on the first message215, the second device may identify the resources720for receiving the second message, transmitting the third message, and receiving the fourth message.

The receiver810may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to connection setup in OAM-based communication system). Information may be passed on to other components of the device805. The receiver810may utilize a single antenna or a set of multiple antennas.

The transmitter815may provide a means for transmitting signals generated by other components of the device805. For example, the transmitter815may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to connection setup in OAM-based communication system). In some examples, the transmitter815may be co-located with a receiver810in a transceiver module. The transmitter815may utilize a single antenna or a set of multiple antennas.

The communications manager820, the receiver810, the transmitter815, or various combinations thereof or various components thereof may be examples of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager820, the receiver810, the transmitter815, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager820may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver810, the transmitter815, or both. For example, the communications manager820may receive information from the receiver810, send information to the transmitter815, or be integrated in combination with the receiver810, the transmitter815, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager820may support wireless communication at a first device in accordance with examples as disclosed herein. For example, the communications manager820may be configured as or otherwise support a means for transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The communications manager820may be configured as or otherwise support a means for receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The communications manager820may be configured as or otherwise support a means for transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The communications manager820may be configured as or otherwise support a means for transmitting the signal to the second device based on the second positional information. The communications manager820may be configured as or otherwise support a means for receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

By including or configuring the communications manager820in accordance with examples as described herein, the device805(e.g., a processor controlling or otherwise coupled with the receiver810, the transmitter815, the communications manager820, or a combination thereof) may support techniques for devices (e.g., device805and another device) to successfully align with each other. Successful alignment may enable more efficient communications. For instance, a range of communications or a received power of a signal may increase when two devices are aligned with each other.

FIG.9shows a block diagram900of a device905that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The device905may be an example of aspects of a device805or a UE115as described herein. The device905may include a receiver910, a transmitter915, and a communications manager920. The device905may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The receiver910may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to connection setup in OAM-based communication system). Information may be passed on to other components of the device905. The receiver910may utilize a single antenna or a set of multiple antennas.

The transmitter915may provide a means for transmitting signals generated by other components of the device905. For example, the transmitter915may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to connection setup in OAM-based communication system). In some examples, the transmitter915may be co-located with a receiver910in a transceiver module. The transmitter915may utilize a single antenna or a set of multiple antennas.

The device905, or various components thereof, may be an example of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager920may include a first message transmitter925, a second message receiver930, a third message transmitter935, a signal transmitter940, a fourth message receiver945, or any combination thereof. The communications manager920may be an example of aspects of a communications manager820as described herein. In some examples, the communications manager920, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver910, the transmitter915, or both. For example, the communications manager920may receive information from the receiver910, send information to the transmitter915, or be integrated in combination with the receiver910, the transmitter915, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager920may support wireless communication at a first device in accordance with examples as disclosed herein. The first message transmitter925may be configured as or otherwise support a means for transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The second message receiver930may be configured as or otherwise support a means for receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The third message transmitter935may be configured as or otherwise support a means for transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The signal transmitter940may be configured as or otherwise support a means for transmitting the signal to the second device based on the second positional information. The fourth message receiver945may be configured as or otherwise support a means for receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

FIG.10shows a block diagram1000of a communications manager1020that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The communications manager1020may be an example of aspects of a communications manager820, a communications manager920, or both, as described herein. The communications manager1020, or various components thereof, may be an example of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager1020may include a first message transmitter1025, a second message receiver1030, a third message transmitter1035, a signal transmitter1040, a fourth message receiver1045, a data transmission communication component1050, a parameter identification component1055, a configuration receiver1060, a WUS component1065, a configuration transmitter1070, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The communications manager1020may support wireless communication at a first device in accordance with examples as disclosed herein. The first message transmitter1025may be configured as or otherwise support a means for transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The second message receiver1030may be configured as or otherwise support a means for receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The third message transmitter1035may be configured as or otherwise support a means for transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The signal transmitter1040may be configured as or otherwise support a means for transmitting the signal to the second device based on the second positional information. The fourth message receiver1045may be configured as or otherwise support a means for receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

In some examples, a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples, a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples, the first message further includes a first set of orbital angular momentum parameters associated with transmissions by the first device.

In some examples, a list of candidate orbital angular momentum modes associated with the transmissions by the first device. In some examples, a quantity of downlink transmitter circles associated with the first device. In some examples, a radius associated with each of the downlink transmitter circles. In some examples, a quantity of antenna elements associated with each of the downlink transmitter circles. In some examples, a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink transmitter circles. In some examples, a quantity of uplink receiver circles associated with reception of the transmissions by the first device. In some examples, a radius associated with each of the uplink receiver circles. In some examples, a quantity of antenna elements associated with each of the uplink receiver circles. In some examples, a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink receiver circles.

In some examples, the second message includes a second set of orbital angular momentum parameters associated with transmissions by the second device.

In some examples, a list of candidate orbital angular momentum modes associated with the transmissions by the second device. In some examples, a quantity of uplink transmitter circles associated with the second device. In some examples, a radius associated with each of the uplink transmitter circles. In some examples, a quantity of antenna elements associated with each of the uplink transmitter circles. In some examples, a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink transmitter circles. In some examples, a quantity of downlink receiver circles associated with the first device. In some examples, a radius associated with each of the downlink receiver circles. In some examples, a quantity of antenna elements associated with each of the downlink receiver circles. In some examples, a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink receiver circles.

In some examples, the directional alignment information includes steering information associated with the signal, the steering information including a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

In some examples, the fourth message further includes an indication of a successful alignment between the first device and the second device, and the data transmission communication component1050may be configured as or otherwise support a means for communicating one or more data transmissions with the second device according to a set of orbital angular momentum modes based on the successful alignment.

In some examples, to support communicating the one or more data transmissions, the configuration transmitter1070may be configured as or otherwise support a means for transmitting, via the first orbital angular momentum mode, a configuration message associated with one or more downlink channel transmissions, the configuration message indicating a set of configured orbital angular momentum modes for the one or more downlink channel transmissions, where the set of configured orbital angular momentum modes includes two or more orbital angular momentum modes of the set of orbital angular momentum modes.

In some examples, the parameter identification component1055may be configured as or otherwise support a means for identifying a set of parameters associated with transmitting the first message, the set of parameters including a periodicity associated with transmitting the first message.

In some examples, the first message indicates a set of resources allocated for receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

In some examples, the configuration receiver1060may be configured as or otherwise support a means for receiving a configuration indicating a set of resources allocated for transmitting the first message, receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

In some examples, the WUS component1065may be configured as or otherwise support a means for monitoring for a wake-up signal over a set of resources allocated for the wake-up signal, where the monitoring is via the first orbital angular momentum mode. In some examples, the WUS component1065may be configured as or otherwise support a means for receiving the wake-up signal based on the monitoring, where transmitting the first message is based on receiving the wake-up signal.

In some examples, the signal includes an optical signal.

In some examples, the signal includes a radio signal.

In some examples, the signal includes a directional signal associated with one or more beams.

In some examples, the signal includes an omnidirectional signal.

In some examples, the first orbital angular momentum mode includes orbital angular momentum mode.

In some examples, transmitting the first message, the third message, or both includes using a center radiator of one or more transmitter circles of the first device or one or more uniform circular array radiators of the one or more transmitter circles of the first device.

FIG.11shows a diagram of a system1100including a device1105that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The device1105may be an example of or include the components of a device805, a device905, or a UE115as described herein. The device1105may communicate (e.g., wirelessly) with one or more network entities105, one or more UEs115, or any combination thereof. The device1105may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager1120, an input/output (I/O) controller1110, a transceiver1115, an antenna1125, a memory1130, code1135, and a processor1140. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus1145).

The I/O controller1110may manage input and output signals for the device1105. The I/O controller1110may also manage peripherals not integrated into the device1105. In some cases, the I/O controller1110may represent a physical connection or port to an external peripheral. In some cases, the I/O controller1110may utilize an operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operating system. Additionally or alternatively, the I/O controller1110may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller1110may be implemented as part of a processor, such as the processor1140. In some cases, a user may interact with the device1105via the I/O controller1110or via hardware components controlled by the I/O controller1110.

The memory1130may include random access memory (RAM) and read-only memory (ROM). The memory1130may store computer-readable, computer-executable code1135including instructions that, when executed by the processor1140, cause the device1105to perform various functions described herein. The code1135may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code1135may not be directly executable by the processor1140but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory1130may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor1140may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor1140may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor1140. The processor1140may be configured to execute computer-readable instructions stored in a memory (e.g., the memory1130) to cause the device1105to perform various functions (e.g., functions or tasks supporting connection setup in OAM-based communication system). For example, the device1105or a component of the device1105may include a processor1140and memory1130coupled with or to the processor1140, the processor1140and memory1130configured to perform various functions described herein.

The communications manager1120may support wireless communication at a first device in accordance with examples as disclosed herein. For example, the communications manager1120may be configured as or otherwise support a means for transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The communications manager1120may be configured as or otherwise support a means for receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The communications manager1120may be configured as or otherwise support a means for transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The communications manager1120may be configured as or otherwise support a means for transmitting the signal to the second device based on the second positional information. The communications manager1120may be configured as or otherwise support a means for receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

By including or configuring the communications manager1120in accordance with examples as described herein, the device1105may support techniques for devices (e.g., device1105and another device) to successfully align with each other. Successful alignment may enable more efficient communications. For instance, a range of communications or a received power of a signal may increase when two devices are aligned with each other.

In some examples, the communications manager1120may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver1115, the one or more antennas1125, or any combination thereof. For example, the communications manager1120may be configured to receive or transmit messages or other signals as described herein via the transceiver1115. Although the communications manager1120is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager1120may be supported by or performed by the processor1140, the memory1130, the code1135, or any combination thereof. For example, the code1135may include instructions executable by the processor1140to cause the device1105to perform various aspects of connection setup in OAM-based communication system as described herein, or the processor1140and the memory1130may be otherwise configured to perform or support such operations.

FIG.12shows a block diagram1200of a device1205that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The device1205may be an example of aspects of a network entity105as described herein. The device1205may include a receiver1210, a transmitter1215, and a communications manager1220. The device1205may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The transmitter1215may provide a means for outputting (e.g., transmitting, providing, conveying, sending) information generated by other components of the device1205. For example, the transmitter1215may output information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack). In some examples, the transmitter1215may support outputting information by transmitting signals via one or more antennas. Additionally, or alternatively, the transmitter1215may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter1215and the receiver1210may be co-located in a transceiver, which may include or be coupled with a modem.

The communications manager1220, the receiver1210, the transmitter1215, or various combinations thereof or various components thereof may be examples of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager1220, the receiver1210, the transmitter1215, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager1220may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver1210, the transmitter1215, or both. For example, the communications manager1220may receive information from the receiver1210, send information to the transmitter1215, or be integrated in combination with the receiver1210, the transmitter1215, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager1220may support wireless communication at a second device in accordance with examples as disclosed herein. For example, the communications manager1220may be configured as or otherwise support a means for receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The communications manager1220may be configured as or otherwise support a means for transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The communications manager1220may be configured as or otherwise support a means for receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The communications manager1220may be configured as or otherwise support a means for receiving the signal from the first device based on the second positional information. The communications manager1220may be configured as or otherwise support a means for transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

By including or configuring the communications manager1220in accordance with examples as described herein, the device1205(e.g., a processor controlling or otherwise coupled with the receiver1210, the transmitter1215, the communications manager1220, or a combination thereof) may support techniques for devices (e.g., device1205and another device) to successfully align with each other. Successful alignment may enable more efficient communications. For instance, a range of communications or a received power of a signal may increase when two devices are aligned with each other.

FIG.13shows a block diagram1300of a device1305that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The device1305may be an example of aspects of a device1205or a network entity105as described herein. The device1305may include a receiver1310, a transmitter1315, and a communications manager1320. The device1305may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The transmitter1315may provide a means for outputting (e.g., transmitting, providing, conveying, sending) information generated by other components of the device1305. For example, the transmitter1315may output information such as user data, control information, or any combination thereof (e.g., I/Q samples, symbols, packets, protocol data units, service data units) associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack). In some examples, the transmitter1315may support outputting information by transmitting signals via one or more antennas. Additionally, or alternatively, the transmitter1315may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter1315and the receiver1310may be co-located in a transceiver, which may include or be coupled with a modem.

The device1305, or various components thereof, may be an example of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager1320may include a first message receiver1325, a second message transmitter1330, a third message receiver1335, a signal receiver1340, a fourth message transmitter1345, or any combination thereof. The communications manager1320may be an example of aspects of a communications manager1220as described herein. In some examples, the communications manager1320, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver1310, the transmitter1315, or both. For example, the communications manager1320may receive information from the receiver1310, send information to the transmitter1315, or be integrated in combination with the receiver1310, the transmitter1315, or both to obtain information, output information, or perform various other operations as described herein.

The communications manager1320may support wireless communication at a second device in accordance with examples as disclosed herein. The first message receiver1325may be configured as or otherwise support a means for receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The second message transmitter1330may be configured as or otherwise support a means for transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The third message receiver1335may be configured as or otherwise support a means for receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The signal receiver1340may be configured as or otherwise support a means for receiving the signal from the first device based on the second positional information. The fourth message transmitter1345may be configured as or otherwise support a means for transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

FIG.14shows a block diagram1400of a communications manager1420that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The communications manager1420may be an example of aspects of a communications manager1220, a communications manager1320, or both, as described herein. The communications manager1420, or various components thereof, may be an example of means for performing various aspects of connection setup in OAM-based communication system as described herein. For example, the communications manager1420may include a first message receiver1425, a second message transmitter1430, a third message receiver1435, a signal receiver1440, a fourth message transmitter1445, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) which may include communications within a protocol layer of a protocol stack, communications associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack, within a device, component, or virtualized component associated with a network entity105, between devices, components, or virtualized components associated with a network entity105), or any combination thereof.

The communications manager1420may support wireless communication at a second device in accordance with examples as disclosed herein. The first message receiver1425may be configured as or otherwise support a means for receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The second message transmitter1430may be configured as or otherwise support a means for transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The third message receiver1435may be configured as or otherwise support a means for receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The signal receiver1440may be configured as or otherwise support a means for receiving the signal from the first device based on the second positional information. The fourth message transmitter1445may be configured as or otherwise support a means for transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

In some examples, a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples, a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

In some examples, the first message further includes a first set of orbital angular momentum parameters associated with transmissions by the first device.

In some examples, the signal includes an optical signal.

In some examples, the signal includes a radio signal.

In some examples, the signal includes a directional signal associated with one or more beams.

In some examples, the signal includes an omnidirectional signal.

FIG.15shows a diagram of a system1500including a device1505that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The device1505may be an example of or include the components of a device1205, a device1305, or a network entity105as described herein. The device1505may communicate with one or more network entities105, one or more UEs115, or any combination thereof, which may include communications over one or more wired interfaces, over one or more wireless interfaces, or any combination thereof. The device1505may include components that support outputting and obtaining communications, such as a communications manager1520, a transceiver1510, an antenna1515, a memory1525, code1530, and a processor1535. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus1540).

The transceiver1510may support bi-directional communications via wired links, wireless links, or both as described herein. In some examples, the transceiver1510may include a wired transceiver and may communicate bi-directionally with another wired transceiver. Additionally, or alternatively, in some examples, the transceiver1510may include a wireless transceiver and may communicate bi-directionally with another wireless transceiver. In some examples, the device1505may include one or more antennas1515, which may be capable of transmitting or receiving wireless transmissions (e.g., concurrently). The transceiver1510may also include a modem to modulate signals, to provide the modulated signals for transmission (e.g., by one or more antennas1515, by a wired transmitter), to receive modulated signals (e.g., from one or more antennas1515, from a wired receiver), and to demodulate signals. The transceiver1510, or the transceiver1510and one or more antennas1515or wired interfaces, where applicable, may be an example of a transmitter1215, a transmitter1315, a receiver1210, a receiver1310, or any combination thereof or component thereof, as described herein. In some examples, the transceiver may be operable to support communications via one or more communications links (e.g., a communication link125, a backhaul communication link120, a midhaul communication link162, a fronthaul communication link168).

The memory1525may include RAM and ROM. The memory1525may store computer-readable, computer-executable code1530including instructions that, when executed by the processor1535, cause the device1505to perform various functions described herein. The code1530may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code1530may not be directly executable by the processor1535but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory1525may contain, among other things, a BIOS which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor1535may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, a microcontroller, a programmable logic device, discrete gate or transistor logic, a discrete hardware component, or any combination thereof). In some cases, the processor1535may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor1535. The processor1535may be configured to execute computer-readable instructions stored in a memory (e.g., the memory1525) to cause the device1505to perform various functions (e.g., functions or tasks supporting connection setup in OAM-based communication system). For example, the device1505or a component of the device1505may include a processor1535and memory1525coupled with the processor1535, the processor1535and memory1525configured to perform various functions described herein. The processor1535may be an example of a cloud-computing platform (e.g., one or more physical nodes and supporting software such as operating systems, virtual machines, or container instances) that may host the functions (e.g., by executing code1530) to perform the functions of the device1505.

In some examples, a bus1540may support communications of (e.g., within) a protocol layer of a protocol stack. In some examples, a bus1540may support communications associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack), which may include communications performed within a component of the device1505, or between different components of the device1505that may be co-located or located in different locations (e.g., where the device1505may refer to a system in which one or more of the communications manager1520, the transceiver1510, the memory1525, the code1530, and the processor1535may be located in one of the different components or divided between different components).

The communications manager1520may support wireless communication at a second device in accordance with examples as disclosed herein. For example, the communications manager1520may be configured as or otherwise support a means for receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The communications manager1520may be configured as or otherwise support a means for transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The communications manager1520may be configured as or otherwise support a means for receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The communications manager1520may be configured as or otherwise support a means for receiving the signal from the first device based on the second positional information. The communications manager1520may be configured as or otherwise support a means for transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

By including or configuring the communications manager1520in accordance with examples as described herein, the device1505may support techniques for devices (e.g., device1505and another device) to successfully align with each other. Successful alignment may enable more efficient communications. For instance, a range of communications or a received power of a signal may increase when two devices are aligned with each other.

In some examples, the communications manager1520may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the transceiver1510, the one or more antennas1515(e.g., where applicable), or any combination thereof. Although the communications manager1520is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager1520may be supported by or performed by the processor1535, the memory1525, the code1530, the transceiver1510, or any combination thereof. For example, the code1530may include instructions executable by the processor1535to cause the device1505to perform various aspects of connection setup in OAM-based communication system as described herein, or the processor1535and the memory1525may be otherwise configured to perform or support such operations.

At1605, the method may include transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The operations of1605may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1605may be performed by a first message transmitter1025as described with reference toFIG.10.

At1610, the method may include receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The operations of1610may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1610may be performed by a second message receiver1030as described with reference toFIG.10.

At1615, the method may include transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of1615may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1615may be performed by a third message transmitter1035as described with reference toFIG.10.

At1620, the method may include transmitting the signal to the second device based on the second positional information. The operations of1620may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1620may be performed by a signal transmitter1040as described with reference toFIG.10.

At1625, the method may include receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of1625may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1625may be performed by a fourth message receiver1045as described with reference toFIG.10.

At1705, the method may include transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The operations of1705may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1705may be performed by a first message transmitter1025as described with reference toFIG.10.

At1710, the method may include receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The operations of1710may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1710may be performed by a second message receiver1030as described with reference toFIG.10.

At1715, the method may include transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of1715may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1715may be performed by a third message transmitter1035as described with reference toFIG.10.

At1720, the method may include transmitting the signal to the second device based on the second positional information. The operations of1720may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1720may be performed by a signal transmitter1040as described with reference toFIG.10.

At1725, the method may include receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of1725may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1725may be performed by a fourth message receiver1045as described with reference toFIG.10.

At1730, the method may include a transmitter orbital angular momentum circle center associating with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof. The operations of1730may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1730may be performed by a first message transmitter1025as described with reference toFIG.10.

At1805, the method may include transmitting a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device. The operations of1805may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1805may be performed by a first message transmitter1025as described with reference toFIG.10.

At1810, the method may include receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with a second device. The operations of1810may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1810may be performed by a second message receiver1030as described with reference toFIG.10.

At1815, the method may include transmitting, to the second device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of1815may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1815may be performed by a third message transmitter1035as described with reference toFIG.10.

At1820, the method may include transmitting the signal to the second device based on the second positional information. The operations of1820may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1820may be performed by a signal transmitter1040as described with reference toFIG.10.

At1825, the method may include receiving, from the second device via the first orbital angular momentum mode, a fourth message based on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of1825may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1825may be performed by a fourth message receiver1045as described with reference toFIG.10.

At1830, the method may include a transmitter orbital angular momentum circle center associating with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof. The operations of1830may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1830may be performed by a second message receiver1030as described with reference toFIG.10.

FIG.19shows a flowchart illustrating a method1900that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The operations of the method1900may be implemented by a network entity or its components as described herein. For example, the operations of the method1900may be performed by a network entity as described with reference toFIGS.1through7and12through15. In some examples, a network entity may execute a set of instructions to control the functional elements of the network entity to perform the described functions. Additionally, or alternatively, the network entity may perform aspects of the described functions using special-purpose hardware.

At1905, the method may include receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The operations of1905may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1905may be performed by a first message receiver1425as described with reference toFIG.14.

At1910, the method may include transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The operations of1910may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1910may be performed by a second message transmitter1430as described with reference toFIG.14.

At1915, the method may include receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of1915may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1915may be performed by a third message receiver1435as described with reference toFIG.14.

At1920, the method may include receiving the signal from the first device based on the second positional information. The operations of1920may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1920may be performed by a signal receiver1440as described with reference toFIG.14.

At1925, the method may include transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of1925may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of1925may be performed by a fourth message transmitter1445as described with reference toFIG.14.

FIG.20shows a flowchart illustrating a method2000that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The operations of the method2000may be implemented by a network entity or its components as described herein. For example, the operations of the method2000may be performed by a network entity as described with reference toFIGS.1through7and12through15. In some examples, a network entity may execute a set of instructions to control the functional elements of the network entity to perform the described functions. Additionally, or alternatively, the network entity may perform aspects of the described functions using special-purpose hardware.

At2005, the method may include receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The operations of2005may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2005may be performed by a first message receiver1425as described with reference toFIG.14.

At2010, the method may include transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The operations of2010may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2010may be performed by a second message transmitter1430as described with reference toFIG.14.

At2015, the method may include receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of2015may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2015may be performed by a third message receiver1435as described with reference toFIG.14.

At2020, the method may include receiving the signal from the first device based on the second positional information. The operations of2020may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2020may be performed by a signal receiver1440as described with reference toFIG.14.

At2025, the method may include transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of2025may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2025may be performed by a fourth message transmitter1445as described with reference toFIG.14.

At2030, the method may include a transmitter orbital angular momentum circle center associating with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof. The operations of2030may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2030may be performed by a first message receiver1425as described with reference toFIG.14.

FIG.21shows a flowchart illustrating a method2100that supports connection setup in OAM-based communication system in accordance with one or more aspects of the present disclosure. The operations of the method2100may be implemented by a network entity or its components as described herein. For example, the operations of the method2100may be performed by a network entity as described with reference toFIGS.1through7and12through15. In some examples, a network entity may execute a set of instructions to control the functional elements of the network entity to perform the described functions. Additionally, or alternatively, the network entity may perform aspects of the described functions using special-purpose hardware.

At2105, the method may include receiving a first message via a first orbital angular momentum mode, the first message including a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device. The operations of2105may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2105may be performed by a first message receiver1425as described with reference toFIG.14.

At2110, the method may include transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message including second positional information associated with a second orbital angular momentum circle center associated with the second device. The operations of2110may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2110may be performed by a second message transmitter1430as described with reference toFIG.14.

At2115, the method may include receiving, from the first device via the first orbital angular momentum mode, a third message based on the second message, the third message including directional alignment information associated with transmitting a signal. The operations of2115may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2115may be performed by a third message receiver1435as described with reference toFIG.14.

At2120, the method may include receiving the signal from the first device based on the second positional information. The operations of2120may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2120may be performed by a signal receiver1440as described with reference toFIG.14.

At2125, the method may include transmitting, to the first device via the first orbital angular momentum mode, a fourth message based on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device. The operations of2125may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2125may be performed by a fourth message transmitter1445as described with reference toFIG.14.

At2130, the method may include a transmitter orbital angular momentum circle center associating with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof. The operations of2130may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of2130may be performed by a second message transmitter1430as described with reference toFIG.14.

Aspect 1: A method for wireless communication at a first device, comprising: transmitting a first message via a first orbital angular momentum mode, the first message comprising a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with the first device; receiving, via the first orbital angular momentum mode, a second message responsive to the first message, the second message comprising second positional information associated with a second orbital angular momentum circle center associated with a second device; transmitting, to the second device via the first orbital angular momentum mode, a third message based at least in part on the second message, the third message comprising directional alignment information associated with transmitting a signal; transmitting the signal to the second device based at least in part on the second positional information; and receiving, from the second device via the first orbital angular momentum mode, a fourth message based at least in part on transmitting the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

Aspect 2: The method of aspect 1, wherein the first positional information is associated with downlink transmissions by the first device, the first positional information comprising a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

Aspect 3: The method of any of aspects 1 through 2, wherein the second positional information is associated with uplink transmissions by the second device, the second positional information comprising a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

Aspect 4: The method of any of aspects 1 through 3, wherein the first message further comprises a first set of orbital angular momentum parameters associated with transmissions by the first device.

Aspect 5: The method of aspect 4, wherein the first set of orbital angular momentum parameters associated with the transmissions by the first device further comprise one or more of a list of candidate orbital angular momentum modes associated with the transmissions by the first device; a quantity of downlink transmitter circles associated with the first device; a radius associated with each of the downlink transmitter circles; a quantity of antenna elements associated with each of the downlink transmitter circles; a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink transmitter circles; a quantity of uplink receiver circles associated with reception of the transmissions by the first device; a radius associated with each of the uplink receiver circles; a quantity of antenna elements associated with each of the uplink receiver circles; or a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink receiver circles.

Aspect 6: The method of any of aspects 1 through 5, wherein the second message comprises a second set of orbital angular momentum parameters associated with transmissions by the second device.

Aspect 7: The method of aspect 6, wherein the second set of orbital angular momentum parameters associated with the transmissions by the second device further comprise one or more of a list of candidate orbital angular momentum modes associated with the transmissions by the second device; a quantity of uplink transmitter circles associated with the second device; a radius associated with each of the uplink transmitter circles; a quantity of antenna elements associated with each of the uplink transmitter circles; a quantity of orbital angular momentum modes simultaneously used for one or more of the uplink transmitter circles; a quantity of downlink receiver circles associated with the first device; a radius associated with each of the downlink receiver circles; a quantity of antenna elements associated with each of the downlink receiver circles; or a quantity of orbital angular momentum modes simultaneously used for one or more of the downlink receiver circles.

Aspect 8: The method of any of aspects 1 through 7, wherein the directional alignment information comprises steering information associated with the signal, the steering information comprising a wavelength of the signal, a polarization of the signal, a laser mode associated with the signal, or a combination thereof.

Aspect 9: The method of any of aspects 1 through 8, wherein the fourth message further comprises an indication of a successful alignment between the first device and the second device, the method further comprising: communicating one or more data transmissions with the second device according to a set of orbital angular momentum modes based at least in part on the successful alignment.

Aspect 10: The method of aspect 9, wherein communicating the one or more data transmissions comprises: transmitting, via the first orbital angular momentum mode, a configuration message associated with one or more downlink channel transmissions, the configuration message indicating a set of configured orbital angular momentum modes for the one or more downlink channel transmissions, wherein the set of configured orbital angular momentum modes comprises two or more orbital angular momentum modes of the set of orbital angular momentum modes.

Aspect 11: The method of any of aspects 1 through 10, further comprising: identifying a set of parameters associated with transmitting the first message, the set of parameters comprising a periodicity associated with transmitting the first message.

Aspect 12: The method of any of aspects 1 through 11, wherein the first message indicates a set of resources allocated for receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

Aspect 13: The method of any of aspects 1 through 12, further comprising: receiving a configuration indicating a set of resources allocated for transmitting the first message, receiving the second message, transmitting the third message, receiving the fourth message, or a combination thereof.

Aspect 14: The method of any of aspects 1 through 13, further comprising: monitoring for a wake-up signal over a set of resources allocated for the wake-up signal, wherein the monitoring is via the first orbital angular momentum mode; and receiving the wake-up signal based at least in part on the monitoring, wherein transmitting the first message is based at least in part on receiving the wake-up signal.

Aspect 15: The method of any of aspects 1 through 14, wherein the signal comprises an optical signal.

Aspect 16: The method of any of aspects 1 through 15, wherein the signal comprises a radio signal.

Aspect 17: The method of any of aspects 1 through 16, wherein the signal comprises a directional signal associated with one or more beams.

Aspect 18: The method of any of aspects 1 through 17, wherein the signal comprises an omnidirectional signal.

Aspect 19: The method of any of aspects 1 through 18, wherein the first orbital angular momentum mode comprises orbital angular momentum mode.

Aspect 20: The method of aspect 19, wherein transmitting the first message, the third message, or both comprises using a center radiator of one or more transmitter circles of the first device or one or more uniform circular array radiators of the one or more transmitter circles of the first device.

Aspect 21: A method for wireless communication at a second device, comprising: receiving a first message via a first orbital angular momentum mode, the first message comprising a synchronization signal and first positional information associated with a first orbital angular momentum circle center associated with a first device; transmitting, via the first orbital angular momentum mode, a second message responsive to the first message, the second message comprising second positional information associated with a second orbital angular momentum circle center associated with the second device; receiving, from the first device via the first orbital angular momentum mode, a third message based at least in part on the second message, the third message comprising directional alignment information associated with transmitting a signal; receiving the signal from the first device based at least in part on the second positional information; and transmitting, to the first device via the first orbital angular momentum mode, a fourth message based at least in part on receiving the third message and the signal, the fourth message indicating whether the signal was successfully received by the second device.

Aspect 22: The method of aspect 21, wherein the first positional information is associated with downlink transmissions by the first device, the first positional information comprising a transmitter orbital angular momentum circle center associated with the first device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the first device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

Aspect 23: The method of any of aspects 21 through 22, wherein the second positional information is associated with uplink transmissions by the second device, the second positional information comprising a transmitter orbital angular momentum circle center associated with the second device, direction information associated with the transmitter orbital angular momentum circle center, a receiver orbital angular momentum circle center associated with the second device, direction information associated with the receiver orbital angular momentum circle center, or a combination thereof.

Aspect 24: The method of any of aspects 21 through 23, wherein the first message further comprises a first set of orbital angular momentum parameters associated with transmissions by the first device.

Aspect 25: The method of any of aspects 21 through 24, wherein the signal comprises an optical signal.

Aspect 26: The method of any of aspects 21 through 25, wherein the signal comprises a radio signal.

Aspect 27: The method of any of aspects 21 through 26, wherein the signal comprises a directional signal associated with one or more beams.

Aspect 28: The method of any of aspects 21 through 27, wherein the signal comprises an omnidirectional signal.

Aspect 29: An apparatus, comprising a memory, transceiver, and at least one processor coupled with memory and the transceiver, the at least one processor configured to cause the apparatus to perform a method of any of aspects 1 through 20.

Aspect 30: An apparatus for wireless communication at a first device, comprising at least one means for performing a method of any of aspects 1 through 20.

Aspect 32: An apparatus, comprising a memory, transceiver, and at least one processor coupled with the memory and the transceiver, the at least one processor configured to cause the apparatus to perform a method of any of aspects 21 through 28.

Aspect 33: An apparatus for wireless communication at a second device, comprising at least one means for performing a method of any of aspects 21 through 28.