US-12621049-B2 - Transmit diversity across orbital angular momentum modes

US12621049B2US 12621049 B2US12621049 B2US 12621049B2US-12621049-B2

Abstract

Methods, systems, and devices for determining a transmit diversity across orbital angular momentum (OAM) modes are described. In some examples, a first device may select a subset of OAM modes for a transmit diversity scheme associated with communications between the first device and a second device. The first device may transmit an indication of the transmit diversity scheme, where the transmit diversity scheme may indicate the subset of OAM modes to the second device. The first device may then transmit signaling (e.g., a data packet, one or more signals, a data stream) to the second device using a set of transmitter circles of the first device. In response, the second device may transmit a feedback message, indicating signal strength measurements associated with one or more OAM modes. The first device may determine a set of OAM modes to use for subsequent signaling based on the feedback message.

Inventors

Danlu Zhang
Min Huang
Yu Zhang
Hao Xu

Assignees

QUALCOMM INCORPORATED

Dates

Publication Date: 20260505
Application Date: 20210713

Claims (20)

1 . A method for wireless communications at a first device, comprising: selecting, from a plurality of orbital angular momentum modes, a subset of orbital angular momentum modes for a transmit diversity scheme associated with communications between the first device and a second device, the subset comprising a first orbital angular momentum mode of the plurality of orbital angular momentum modes and a second orbital angular momentum mode of the plurality of orbital angular momentum modes; transmitting, to the second device, an indication of the transmit diversity scheme associated with communications between the first device and the second device, the transmit diversity scheme indicating the subset of orbital angular momentum modes; and transmitting, based at least in part on the transmit diversity scheme, a data packet to the second device using a set of transmitter circles of the first device, the set of transmitter circles corresponding to both the first orbital angular momentum mode and the second orbital angular momentum mode.
2 . The method of claim 1 , further comprising: receiving, from the second device, a feedback message for the data packet, the feedback message indicating a signal strength of the data packet and one or more orbital angular momentum modes for the transmit diversity scheme.
3 . The method of claim 1 , further comprising: transmitting a control message corresponding to the data packet, the control message instructing the second device to provide feedback for the data packet based at least in part on the first orbital angular momentum mode and the second orbital angular momentum mode.
4 . The method of claim 3 , further comprising: receiving, from the second device, a feedback message for the data packet, the feedback message indicating a signal strength of the data packet for a combination of the first orbital angular momentum mode and the second orbital angular momentum mode.
5 . The method of claim 1 , further comprising: transmitting a control message corresponding to the data packet, the control message indicating the transmit diversity scheme for transmission of the data packet.
6 . The method of claim 1 , further comprising: transmitting one or more signals using a plurality of transmitter circles of the first device, the plurality of transmitter circles corresponding to the plurality of orbital angular momentum modes; and receiving, from the second device, a feedback message for the one or more signals, the feedback message indicating a combination of one or more orbital angular momentum modes of the plurality of orbital angular momentum modes and a signal strength corresponding to the combination of the one or more orbital angular momentum modes.
7 . The method of claim 6 , wherein selecting the subset of orbital angular momentum modes comprises: selecting the subset of orbital angular momentum modes based at least in part on the feedback message, wherein the subset comprises the combination of the one or more orbital angular momentum modes.
8 . The method of claim 6 , wherein the feedback message indicates which of the plurality of orbital angular momentum modes are combined by the second device.
9 . The method of claim 1 , further comprising: transmitting one or more signals using a plurality of transmitter circles of the first device, the plurality of transmitter circles corresponding to the plurality of orbital angular momentum modes; and receiving, from the second device, a feedback message for the one or more signals, the feedback message indicating a respective signal strength for each of the plurality of orbital angular momentum modes.
10 . The method of claim 9 , wherein selecting the subset of orbital angular momentum modes comprises: selecting the subset of orbital angular momentum modes based at least in part on the respective signal strengths for each of the plurality of orbital angular momentum modes.
11 . A method for wireless communications at a first device, comprising: receiving, from a second device, an indication of the transmit diversity scheme associated with communications between the first device and the second device, the transmit diversity scheme indicating a plurality of orbital angular momentum modes for one or more signals from the first device; monitoring for the one or more signals from the first device based at least in part on the transmit diversity scheme; and transmitting a feedback message to the second device based at least in part on the monitoring, the feedback message indicating one or more signal strength measurements for one or more orbital angular momentum modes of the plurality of orbital angular momentum modes, the one or more signal strength measurements associated with the one or more signals.
12 . The method of claim 11 , wherein transmitting the feedback message comprises: transmitting a total signal strength of the one or more signals for a combination of multiple orbital angular momentum modes of the plurality of orbital angular momentum modes.
13 . The method of claim 11 , further comprising: receiving a control message for a data packet, the control message instructing the second device to provide feedback for the data packet based at least in part on a combination of a first orbital angular momentum mode and a second orbital angular momentum mode of the plurality of orbital angular momentum modes, wherein the one or more signal strength measurements for the one or more orbital angular momentum modes correspond to the combination of the first orbital angular momentum mode and the second orbital angular momentum mode.
14 . The method of claim 13 , wherein the control message comprises the indication of the transmit diversity scheme.
15 . The method of claim 11 , further comprising: receiving a control message for a data packet, the control message comprising the indication of the transmit diversity scheme.
16 . The method of claim 11 , further comprising: receiving the one or more signals using a plurality of receiver circles of the first device based at least in part on the monitoring, the plurality of receiver circles corresponding to the plurality of orbital angular momentum modes; determining the one or more signal strength measurements for the one or more signals based at least in part on receiving the one or more signals; and selecting the one or more orbital angular momentum modes of the plurality of orbital angular momentum modes based at least in part on determining the one or more signal strength measurements.
17 . The method of claim 16 , wherein transmitting the feedback message comprises: transmitting a total signal strength for the selected one or more orbital angular momentum modes in the feedback message.
18 . The method of claim 11 , further comprising: receiving the one or more signals using a plurality of receiver circles of the first device based at least in part on the monitoring, the plurality of receiver circles corresponding to the plurality of orbital angular momentum modes; determining a respective signal strength measurement for each of the plurality of orbital angular momentum modes based at least in part on receiving the one or more signals; and transmitting the respective signal strengths for each of the plurality of orbital angular momentum modes in the feedback message.
19 . An apparatus for wireless communications at a first device, comprising: a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: select, from a plurality of orbital angular momentum modes, a subset of orbital angular momentum modes for a transmit diversity scheme associated with communications between the first device and a second device, the subset comprising a first orbital angular momentum mode of the plurality of orbital angular momentum modes and a second orbital angular momentum mode of the plurality of orbital angular momentum modes; transmit, to the second device, an indication of the transmit diversity scheme associated with communications between the first device and the second device, the transmit diversity scheme indicating the subset of orbital angular momentum modes; and transmit, based at least in part on the transmit diversity scheme, a data packet to the second device using a set of transmitter circles of the first device, the set of transmitter circles corresponding to both the first orbital angular momentum mode and the second orbital angular momentum mode.
20 . The apparatus of claim 19 , wherein the instructions are further executable by the processor to cause the apparatus to: receive, from the second device, a feedback message for the data packet, the feedback message indicating a signal strength of the data packet and one or more orbital angular momentum modes for the transmit diversity scheme.

Description

CROSS REFERENCE The present Application is a 371 national stage filing of International PCT Application No. PCT/CN2021/105924 by ZHANG et al. entitled “TRANSMIT DIVERSITY ACROSS ORBITAL ANGULAR MOMENTUM MODES,” filed Jul. 13, 2021, which is assigned to the assignee hereof, and which is expressly incorporated by reference in its entirety herein. FIELD OF TECHNOLOGY The following relates to wireless communications, including transmit diversity across orbital angular momentum modes. BACKGROUND Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE). Efficient techniques for transmission of information in such systems is desirable in order to enhance system throughput and reliability. SUMMARY The described techniques relate to improved methods, systems, devices, and apparatuses that support orbital angular momentum (OAM) mode selection. Generally, the described techniques provide for enhanced OAM multiplexing procedures. In some implementations, 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., uniform circular arrays (UCAs)). The one or more antenna circles may include a center antenna node, center antenna element, center circle, or center antenna array and one or more peripheral antenna circles that enable the first device and the second device to communicate according to one or more OAM modes using the one or more antenna circles. For example, the one or more antenna circles may enable the first and second devices to transmit and receive multiplexed OAM communications. Such multiplexed OAM communications may include multiple OAM waveforms with different OAM states, polarizations, or both. In some aspects, a first device (e.g., a user equipment (UE), base station, integrated access and backhaul (IAB) node, relay node) or a second device (e.g., a UE, base station, IAB node, relay node), or both may determine a transmit diversity scheme for the first device to use for transmitting messages to the second device. For example, the first device, or the second device, or both may be configured to determine one or more OAM modes which may be used for transmissions by the first device (e.g., using one or more antenna circles (e.g., transmitter circles) of the transmitting device). In some cases, the first device may be configured to transmit signals to the second device using a combination of multiple OAM modes. For instance, the first device may transmit a single data stream or packet to the second device using multiple OAM modes. In such a case, the first device, the second device, or both may be configured to determine which OAM modes to use for transmission by the first device. In some cases, a transmitting device may transmit one or more signals according to multiple OAM modes. A receiving device may receive the one or more signals and perform measurements on each of the received signals. In some cases, the receiving device may perform measurements on each of the received signals in accordance with control signaling received from the transmitting device. For example, the transmitting device may transmit control information to the receiving device, where the control information may include an indication that the transmitting device may use multiple OAM modes in subsequent transmissions, an indication of which OAM modes the transmitting device may use, an indication of which OAM modes the receiving device may use, or a combination thereof. In some cases, the receiving device may receive the control information and may perform measurements on the signals using a set of OAM modes (e.g., as indicated in the control information). The receiving device may transmit a measurement report indicating the signal measurements to the transmitting device where the transmitting device may receive the measurement report and may determine which OAM modes correspond to a relati