BACKGROUND

Aspects of the present disclosure relate generally to wireless communication networks, and more particularly, to performing a beam recovery procedure for a first component carrier (CC) using a second component carrier.

Wireless communication networks 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 multiple-access systems 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 code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, and single-carrier frequency division multiple access (SC-FDMA) systems.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. For example, a fifth generation (5G) wireless communications technology (which can be referred to as new radio (NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, 5G communications technology can include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with certain specifications for latency and reliability; and massive machine type communications, which can allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, further improvements in NR communications technology and beyond may be desired.

One such need relates to improvements in beam recovery operations. For example, a UE may use directional transmissions for wireless communications. However, in some cases, the beam direction of the directional transmission may change. In such instance, if the beam is not changed, the communication signal may be compromised or lost. Thus, improvements in beam recovery operations may be desired.

SUMMARY

Features of the present disclosure leverage the availability of multiple component carriers in different frequency bands for beam failure recovery (BFR). In some examples, the base station may configure synchronization signal block (SSB) or channel state information reference signal (CSI-RS) in one component carrier as a reference (e.g., spatial quasi co-location (QCL)) for physical downlink control channel (PDCCH) demodulation reference signal (DMRS) in a different component carrier. In other examples, the base station may configure synchronization signal block (SSB) or channel state information reference signal (CSI-RS) in one component carrier as a reference for candidate beam search for a different component carrier. For example, a user equipment (UE) and the base station may be configured to communicate over multiple component carriers (CCs): for example, first component carrier may be a beam formed millimeter wave (MMW) carrier having a beam recovery procedure and second component carrier may be an assisting carrier such as a sub-6 Ghz or another MMW carrier.

If the UE detects a condition for performing a beam recovery procedure on first component carrier, it may transmit a signal to a serving base station using second component carrier. For example, the UE may transmit a beam recovery scheduling request (BFRR) signal (alternatively referred to as beam recovery signal or a beam recovery scheduling request) using a scheduled uplink resource on second component carrier, scheduling request resource, PUCCH resource, or a random access channel (RACH) resource in order to perform beam recovery for first component carrier.

In one example, a method for wireless communications implemented by a user equipment (UE) is disclosed. The method may include establishing communication with a base station over a first component carrier using one or more beams, and receiving a reference signal on a second component carrier associated with the first component carrier. The method may further include determining a block error ratio (BLER) of a channel transmitted using the one or more beams on the first component carrier based on the reference signal received on the second component carrier. The method may further include determining whether the one or more beams in the first component is failing based on the BLER.

In another example, an apparatus for wireless communications is disclosed. The apparatus may include a processor and a memory storing instructions and in electronic communication with the processor. The processor may be configured to execute the instructions to establish communication with a base station over a first component carrier using one or more beams, and receive a reference signal on a second component carrier associated with the first component carrier. The processor may further be configured to execute the instructions to determine a block error ratio (BLER) of a channel transmitted using the one or more beams on the first component carrier based on the reference signal received on the second component carrier. The processor may further be configured to execute the instructions to determine whether the one or more beams in the first component is failing based on the BLER.

In another example, a computer readable medium storing instructions, executable by a processor, for wireless communications is disclosed. The computer readable medium may include instructions for establishing communication with a base station over a first component carrier using one or more beams, and receiving a reference signal on a second component carrier associated with the first component carrier. The computer readable medium may further include instructions for determining a block error ratio (BLER) of a channel transmitted using the one or more beams on the first component carrier based on the reference signal received on the second component carrier. The computer readable medium may further include instructions for determining whether the one or more beams in the first component is failing based on the BLER.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.

